Researcher Profile and Settings

Master

Affiliation (Master)

• Faculty of Engineering　Sustainable Resources Engineering　Resources Engineering

Affiliation (Master)

• Faculty of Engineering　Sustainable Resources Engineering　Resources Engineering

researchmap

Profile and Settings

Affiliation

• Hokkaido University, Faculty of Engineering, Professor

Degree

• Doctor (Engineering)（Hokkaido University）
• Master(Engineering)（Hokkaido University）

Profile and Settings

• Contact Point

  kawamuraeng.hokudai.ac.jp

• Name (Japanese)

  Kawamura

• Name (Kana)

  Youhei

• Name

  200901008736775670

通称等の別名

Yohei

Affiliation

• Hokkaido University, Faculty of Engineering, Professor

Achievement

Research Interests

• Mining Engineering   Mining Informatics   Disaster Control Informatics   

Research Areas

• Energy / Earth resource engineering, energy science
• Social infrastructure (civil Engineering, architecture, disaster prevention) / Geotechnical engineering
• Social infrastructure (civil Engineering, architecture, disaster prevention) / Disaster prevention engineering
• Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Measurement engineering
• Natural sciences / Solid earth science
• Humanities & social sciences / Local studies

Research Experience

• 2021/06 - Today Hokkaido University Faculty of Engineering Professor
• 2019/12 - Today North China Institute of Science and Technology Honorary Professor
• 2016/01 - 2021/05 Akita University Graduate School of International Resource Sciences Professor
• 2017/04 - 2019/03 Akita University International Center for Research and Education on Mineral and Energy Resources
• 2015/04 University of Tsukuba Faculty of Engineering, Information and Systems
• 2014/12 - 2015/03 Curtin University Dept. of Mining Engineering Senior Lecturer
• 2012/05 - 2014/11 Curtin University Dept. of Mining Engineering Lecturer
• 2004/04 - 2012/04 University of Tsukuba Graduate School of Systems and Information Engineering Assistant professor
• 2003/04 - 2004/03 University of Tsukuba Institute of Engineering Mechanics and Systems Assistant Professor

Education

•        - 2003  Graduate School of Hokkaido University  Graduate School, Division of Engineering
•        - 2000/03  Graduate school of Hokkaido University  Graduate School, Division of Engineering

Committee Memberships

• 2018/01 - Today   Arabian Journal of Geosciences   Editor
• 2011   The International Workshop on Soft Computing and Disaster Control   Publication Co-Chairs

Awards

• 2011 Best Cognition Award
   As Publication Co-Chairs 

  受賞者: Youhei Kawamura
• 2011 The 1st International Workshop on Soft Computing and Disaster Control Best Paper Award
   Long-Term Operation of Landslide observation System Using ZigBee Module 

  受賞者: Youhei Kawamura
• 2010/03 日本機械学会 日本機械学会関東支部第16期総会講演会,若手優秀講演賞受賞
   

  受賞者: 川村 洋平若手優秀講演賞
• 2009/11 超音波シンポジウム実行委員会 USE2009奨励賞受賞
   

  受賞者: 川村 洋平奨励賞
• 2008/09 社）資源・素材学会 資源・素材学会平成19年秋季大会，若手ポスター賞受賞
   

  受賞者: 川村 洋平
• 2006/10 第15回ソノケミストリー討論会, ソノケミストリー進歩賞受賞
   

  受賞者: 川村 洋平
• 2002 寒地技術シンポジウム 寒地技術賞（産業部門）
   

  受賞者: 川村 洋平

Published Papers

• Advanced mineralogical classification and concentration estimation in mining with MATLAB-powered hyper-spectral imaging and machine learning

  Natsuo Okada, Brian Bino Sinaice, Jaewon Kim, Hiromasa Nozaki, Kaito Takizawa, Narihiro Owada, Yoko Ohtomo, Youhei Kawamura

  International Journal of Mining, Reclamation and Environment 1 - 21 1748-0930 2024/06/06
• Cone penetration test-based assessment of liquefaction potential using machine and hybrid learning approaches

  Jitendra Khatti, Yewuhalashet Fissha, Kamaldeep Singh Grover, Hajime Ikeda, Hisatoshi Toriya, Tsuyoshi Adachi, Youhei Kawamura

  Multiscale and Multidisciplinary Modeling, Experiments and Design 2520-8160 2024/04/26
• Enhancing Interpretability in Drill Bit Wear Analysis through Explainable Artificial Intelligence: A Grad-CAM Approach

  Lesego Senjoba, Hajime Ikeda, Hisatoshi Toriya, Tsuyoshi Adachi, Youhei Kawamura

  Applied Sciences 14 (9) 3621 - 3621 2024/04/25 

  This study introduces a novel method for analyzing vibration data related to drill bit failure. Our approach combines explainable artificial intelligence (XAI) with convolutional neural networks (CNNs). Conventional signal analysis methods, such as fast Fourier transform (FFT) and wavelet transform (WT), require extensive knowledge of drilling equipment specifications, which limits their adaptability to different conditions. In contrast, our method leverages XAI algorithms applied to CNNs to directly identify fault signatures from vibration signals. The signals are transformed into their frequency components and then employed as inputs to a CNN model, which is trained to detect patterns indicative of drill bit failure. XAI algorithms are then employed to generate attention maps, highlighting regions of interest in the CNN. By scrutinizing these maps, engineers can identify critical frequencies associated with drill bit failure, providing valuable insights for maintenance and optimization. This method offers a transparent and interpretable framework for analyzing vibration data, enabling informed decision-making and proactive maintenance strategies to enhance drilling efficiency and minimize downtime. The integration of XAI with CNNs facilitates a deeper understanding of the root causes of drill bit failure and improves overall drilling performance.
• Enhancing rock fragmentation assessment in mine blasting through machine learning algorithms: a practical approach

  Angesom Gebretsadik, Rahul Kumar, Yewuhalashet Fissha, Yemane Kide, Natsuo Okada, Hajime Ikeda, Arvind Kumar Mishra, Danial Jahed Armaghani, Yoko Ohtomo, Youhei Kawamura

  Discover Applied Sciences 6 (5) 2024/04/25 

  Abstract The optimization of blasting operations greatly benefits from the prediction of rock fragmentation. The main factors that affect fragmentation are rock mass characteristics, blast geometry, and explosive properties. This paper is a step towards the implementation of machine learning and deep learning algorithms for predicting the extent of fragmentation (in percentage) in open pit mining. While various parameters can affect rock fragmentation, this study considers ten among them (i.e., spacing, drill hole diameter, burden, average bench height, powder factor, number of holes, charge per delay, uniaxial compressive strength, specific drilling, and stemming) to train and test the models. However, due to a weak correlation with rock fragmentation, drill diameter, average bench height, compressive strength, stemming, and charge per delay are eliminated to reduce model complexity. A total of 219 data sets having five input features including the number of holes, spacing, burden, specific drilling, and powder factor are used to develop the models. Machine learning models (random forest regression, support vector regression, and XG boost), as well as a deep learning model (neural network regression), are applied to develop a practical way that can optimize the prediction of fragmentation. This study employs performance measures such as R-squared, RMSE, MSE, MAPE, and MAE. The optimization of the model revealed promising results, indicating that the architecture 5-64-32-16-1 exhibits strong performance. Specifically, the model achieved mean squared error (MSE) values of 41.32 and 28.59 on the training and test datasets, respectively. The R² value for both training and test is 0.83. RFR is also performing well compared to SVR and XG boost with MSE values of 12.37 and 9.89 on training and testing data, respectively.in both sets, the R² value is 94%. Based on permutation importance and shapely plot values, it is observed that the powder factor has the highest impact, while the burden has the lowest impact on fragmentation.
• Effect of rock properties on wear and cutting performance of multi blade circular saw with iron based multi-layer diamond segments

  Sohan Singh Rajpurohit, Yewuhalashet Fissha, Rabindra Kumar Sinha, Mujahid Ali, Hajime Ikeda, Wade Ghribi, Taoufik Najeh, Yaser Gamil, Youhei Kawamura

  Scientific Reports 14 (1) 2024/02/26 

  Abstract This study is an attempt for comprehensive, combining experimental data with advanced analytical techniques and machine learning for a thorough understanding of the factors influencing the wear and cutting performance of multi-blade diamond disc cutters on granite blocks. A series of sawing experiments were performed to evaluate the wear and cutting performance of multi blade diamond disc cutters with varying diameters in the processing of large-sized granite blocks. The multi-layer diamond segments comprising the Iron (Fe) based metal matrix were brazed on the sawing blades. The segment’s wear was studied through micrographs and data obtained from the Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray (EDS). Granite rock samples of nine varieties were tested in the laboratory to determine the quantitative rock parameters. The contribution of individual rock parameters and their combined effects on wear and cutting performance of multi blade saw were correlated using statistical machine learning methods. Moreover, predictive models were developed to estimate the wear and cutting rate based on the most significant rock properties. The point load strength index, uniaxial compressive strength, and deformability, Cerchar abrasivity index, and Cerchar hardness index were found to be the significant variables affecting the sawing performance.
• Enhancing the occupational safety and well-being of mining and construction workers: an application of emotional intelligence training (EIT)

  Mukhtar Olalekan Iyanda, Blessing Olamide Taiwo, Yewuhalashet Fissha, Adams Abiodun Akinlabi, Kelebogile Phili, Hajime Ikeda, Youhei Kawamura

  Safety in Extreme Environments 2524-8170 2024/01/08 

  Abstract The mining and construction sector in Nigeria holds a pivotal position in driving economic development; nonetheless, it encounters notable challenges, such as project failures and safety apprehensions. The impact of leadership and safety considerations encompasses a broad spectrum of outcomes for projects and the welfare of individuals. The primary aim of this study is to investigate the possibility of inducing significant changes by introducing emotional intelligence (EI) training in the mining and construction industries in Ogun State, Nigeria. The present study employed a mixed-methods research design to authenticate the significant enhancements in post-training emotional intelligence (EI) levels seen among personnel at New Creation Constructions Ltd. The study included the consideration of five distinct groups (A-E) that were responsible for managing comparable projects. The optimization of Group E’s improvement was achieved by the implementation of Emotional Intelligence (EI) training, and subsequently compared to the performance of the remaining four groups. The safety procedures within Group E experienced a substantial enhancement, marked by an escalated utilization of protective equipment, heightened consciousness of safety measures, and a reinforced dedication to safeguarding the welfare of colleagues. Group E exhibited outstanding project management efficiency, displaying commendable performance in multiple areas such as budget adherence, adherence to safety procedures, stakeholder satisfaction, effective communication, and proficient procurement management. To optimize the benefits outlined above, we suggest implementing emotional intelligence (EI) training programs, leadership development initiatives, stress management interventions, regular evaluations of well-being, and focused research tailored to the specific needs of the organization.
• Development of Wide-Area Mineral Identification System Using Multispectral Camera Mounted on Drone for Beach Placer Deposits

  Hiromasa Nozaki, Natsuo Okada, Brian Bino Sinaice, Yoko Otomo, Youhei Kawamura

  Proceedings of the Second International Conference on Resources and Technology (RESAT 2023) 214 - 232 2731-8079 2023/12/29
• Urban Quarry Ground Vibration Forecasting: A Matrix Factorization Approach

  Hajime Ikeda, Masato Takeuchi, Elsa Pansilvania, Brian Bino Sinaice, Hisatoshi Toriya, Tsuyoshi Adachi, Youhei Kawamura

  Applied Sciences 13 (23) 12674 - 12674 2023/11/25 

  Blasting is routinely carried out in urban quarry sites. Residents or houses around quarry sites are affected by the ground vibrations induced by blasting. Peak Particle Velocity (PPV) is used as a metric to measure ground vibration intensity. Therefore, many prediction models of PPV using experimental methods, statistical methods, and Artificial Neural Networks (ANNs) have been proposed to mitigate this effect. However, prediction models using experimental and statistical methods have a tendency of poor prediction accuracy. In addition, while prediction models using ANNs can produce a highly accurate prediction results, a large amount of measured data is necessarily collected. In an urban quarry site where the number of blastings is limited, it is difficult to collect a lot of measured data. In this study, a new PPV prediction method using Weighted Non-negative Matrix Factorization (WNMF) is proposed. WNMF is a method that approximates a non-negative matrix (including missing data) to the product of two low-dimensional matrices and predicts the missing data. In addition, WNMF is one of the unsupervised learning methods, so it can predict PPV regardless of the amount of data. In this study, PPV was predicted using measured data from 100 sites at the Mikurahana quarry site in Japan. As a result, the proposed method showed higher accuracy when using measured data at 60 sites rather than 100 sites, and the root mean square error for PPV prediction decreased from 0.1759 (100 points) to 0.1378 (60 points).
• Digital Twin Technology in Data Center Simulations: Evaluating the Feasibility of a Former Mine Site

  Hajime Ikeda, Nur Ellisha Binti Mokhtar, Brian Bino Sinaice, Muhammad Ahsan Mahboob, Hisatoshi Toriya, Tsuyoshi Adachi, Youhei Kawamura

  Sustainability 15 (23) 16176 - 16176 2023/11/21 

  Mining activities often deem mine sites as temporary, leading to their eventual reclamation, rehabilitation, or abandonment. This study innovates by proposing the re-purposing of the disused Osarizawa mine in Akita, Japan, leveraging its consistently low tunnel temperatures to establish a data center, thereby offering a sustainable economic avenue to offset reclamation costs. We assessed the feasibility of this transformation by gathering comprehensive environmental data from the site and conducting meticulous ventilation simulations. These simulations explored various scenarios encompassing diverse ventilation configurations, data server room dimensions, thermal outputs, and the inherent cooling capabilities of the proposed humid rooms. By juxtaposing the simulation outcomes with the criteria set forth in the ASHRAE 2011 Thermal Guidelines, we pinpointed the optimal parameters that satisfy the stringent temperature and relative humidity prerequisites essential for a data center’s operation. This research underscores the potential of reimagining abandoned mine sites as strategic assets, providing economic benefits while adhering to critical data center infrastructure standards.
• Soft ground tunnel lithology classification using clustering-guided light gradient boosting machine

  Kursat Kilic, Hajime Ikeda, Tsuyoshi Adachi, Youhei Kawamura

  Journal of Rock Mechanics and Geotechnical Engineering 15 (11) 2857 - 2867 1674-7755 2023/11
• Evaluation and Prediction of Blast-Induced Ground Vibrations: A Gaussian Process Regression (GPR) Approach

  Yewuhalashet Fissha, Hajime Ikeda, Hisatoshi Toriya, Narihiro Owada, Tsuyoshi Adachi, Youhei Kawamura

  Mining 3 (4) 659 - 682 2023/10/26 

  Ground vibration is one of the most hazardous outcomes of blasting. It has a negative impact both on the environment and the human population near to the blasting area. To evaluate the magnitude of blasting vibrations, it is important to consider PPV as a fundamental critical base parameter practice in terms of vibration velocity. This study aims to explore the application of different soft computing techniques, including a Gaussian process regression (GPR), decision tree (DT), and support vector regression (SVR), for the prediction of blast-induced ground vibration (PPV) in quarry mining. The three models were evaluated using classical mathematical evaluation metrics (R2, RMSE, MSE, MAE). The result shows that the GPR model achieves an excellent prediction result; with R2 = 0.94, RMSE = 0.0384, MSE = 0.0014, and MAE = 0.0265, it shows high accuracy in predicting PPV. The Shapley additive explanation (SHAP) results emphasize the importance of understanding the interactions between the various factors and their effects on the vibration assessment. The findings can inform the development of more sustainable and environmentally friendly models for predicting blasting vibrations. Using a GPR to simulate and predict blasting-induced ground vibrations is the study’s main contribution. The GPR can capture complicated, non-linear correlations in data, making it ideal for blast-induced ground vibrations, which are dynamic and nonlinear. By using a Gaussian process regression, we can help companies and researchers improve the safety and efficiency in blast-induced ground vibration environments.
• Deep Learning-Based Estimation of Muckpile Fragmentation Using Simulated 3D Point Cloud Data

  Hajime Ikeda, Taiga Sato, Kohei Yoshino, Hisatoshi Toriya, Hyongdoo Jang, Tsuyoshi Adachi, Itaru Kitahara, Youhei Kawamura

  Applied Sciences (Switzerland) 13 (19) 2023/10 

  This research introduces an innovative technique for estimating the particle size distribution of muckpiles, a determinant significantly affecting the efficiency of mining operations. By employing deep learning and simulation methodologies, this study enhances the precision and efficiency of these vital estimations. Utilizing photogrammetry from multi-view images, the 3D point cloud of a muckpile is meticulously reconstructed. Following this, the particle size distribution is estimated through deep learning methods. The point cloud is partitioned into various segments, and each segment’s distinguishing features are carefully extracted. A shared multilayer perceptron processes these features, outputting scores that, when consolidated, provide a comprehensive estimation of the particle size distribution. Addressing the prevalent issue of limited training data, this study utilizes simulation to generate muckpiles and consequently fabricates an expansive dataset. This dataset comprises 3D point clouds and corresponding particle size distributions. The combination of simulation and deep learning not only improves the accuracy of particle size distribution estimation but also significantly enhances the efficiency, thereby contributing substantially to mining operations.
• Assessment of Charge Initiation Techniques Effect on Blast Fragmentation and Environmental Safety: An Application of WipFrag Software

  Blessing Olamide Taiwo, Yewuhalashet Fissha, Thomas Palangio, Andrew Palangio, Hajime Ikeda, Nageswara Rao Cheepurupalli, Naseer Muhammad Khan, Adams Abiodun Akinlabi, Oluwaseun Victor Famobuwa, Joshua Oluwaseyi Faluyi, Youhei Kawamura

  Mining 3 (3) 532 - 551 2023/09/14 

  Blast charge initiation procedures have a significant impact on both mining safety and production rates. In this study, the inventory benefit of an electric initiation system was investigated to assess its influence on both fragmentation and blast-induced damages. The WipFrag software was used to examine the size distribution and productivity of 12 small-scale blasts initiated by both nonelectric and electric detonators. All blast rounds were initiated with plain-type electric and NONEL detonators. The average burden, spacing, stemming length, and charge weight were, respectively, 0.85 m, 1.10 m, 0.66 m, and 1.1 kg. The results showed that the mesh through which 80% of the blast fragments passed for the electric blast was smaller than the mesh through which the material products from the NONEL blast passed. The results also demonstrated that the generated blast-induced ground vibration (PPV) from all blast rounds for electric blast varied from 0.4–1.2 mm/s and 80–105 dB, while that for nonelectric blast ranged from 0.05–0.2 mm/s and 72–95 dB. As a result, the electric blast initiation technique was found to produce good fragmentation, with a higher percentage of optimum fragment sizes on spec than nonelectrically initiated blasts.
• フィールド科学体験型VRシアターの構築とその教育現場への適用と評価

  田中洋輔, 大塚尚広, 田中優太朗, 川村洋平

  情報処理 64 (8) 2023/08 [Invited]
  
• Application of Bayesian Neural Network (BNN) for the Prediction of Blast-Induced Ground Vibration

  Yewuhalashet Fissha, Hajime Ikeda, Hisatoshi Toriya, Tsuyoshi Adachi, Youhei Kawamura

  Applied Sciences (Switzerland) 13 (5) 2023/03 

  Rock blasting is one of the most common and cost-effective excavation techniques. However, rock blasting has various negative environmental effects, such as air overpressure, fly rock, and ground vibration. Ground vibration is the most hazardous of these inevitable impacts since it has a negative impact not only on the environment of the surrounding area but also on the human population and the rock itself. The PPV is the most critical base parameter practice for understanding, evaluating, and predicting ground vibration in terms of vibration velocity. This study aims to predict the blast-induced ground vibration of the Mikurahana quarry, using Bayesian neural network (BNN) and four machine learning techniques, namely, gradient boosting, k-neighbors, decision tree, and random forest. The proposed models were developed using eight input parameters, one output, and one hundred blasting datasets. The assessment of the suitability of one model in comparison to the others was conducted by using different performance evaluation metrics, such as R, RMSE, and MSE. Hence, this study compared the performances of the BNN model with four machine learning regression analyses, and found that the result from the BNN was superior, with a lower error: R = 0.94, RMSE = 0.17, and MSE = 0.03. Finally, after the evaluation of the models, SHAP was performed to describe the importance of the models’ features and to avoid the black box issue.
• A system of the granite weathering degree assessment using hyperspectral image and CNN

  Jaewon Kim, Youhei Kawamura, Osamu Nishikawa, Brian Bino Sinaice, Natsuo Okada, Shinji Utsuki

  INTERNATIONAL JOURNAL OF MINING RECLAMATION AND ENVIRONMENT 36 (5) 368 - 380 1748-0930 2022/05 

  Due to weathering processes that occur all around the world, rocks that are exposed eventually undergo physical and chemical changes. These weathering processes have the potential to turn fresh rocks into soft and weakened derivatives, leading to the collapse and subsidence of structures, such as tunnels, dams, and others, as well as natural structures, such as cliffs and slopes. This study attempts to employ hyperspectral imaging and a deep learning network called Convolutional Neural Network (CNN) in the effort to achieve a reliable process for rock weathering degree assessment. This study employs a hyperspectral image camera capable of detecting electromagnetic radiation from 400 nm-1000 nm with a spectral resolution of 204 bands. The CNN algorithm used in this study is based on a modified VGG-16 architecture. The total amount of data from granite samples employed amounts to 19,456 files. 80% of the total data were used as learning data and the remaining 20% as testing and validation data. The results show that the system has an average precision of over 94%. The study, therefore, concludes that the conjunction of hyperspectral imaging with CNN is a practicable process for the evaluation of the degree of weathering granite without the need for specialised human expertise or prejudice.
• Use of a DNN-Based Image Translator with Edge Enhancement Technique to Estimate Correspondence between SAR and Optical Images

  Hisatoshi Toriya, Ashraf Dewan, Hajime Ikeda, Narihiro Owada, Mahdi Saadat, Fumiaki Inagaki, Youhei Kawamura, Itaru Kitahara

  Applied Sciences (Switzerland) 12 (9) 2022/05/01 

  In this paper, the local correspondence between synthetic aperture radar (SAR) images and optical images is proposed using an image feature-based keypoint-matching algorithm. To achieve accurate matching, common image features were obtained at the corresponding locations. Since the appearance of SAR and optical images is different, it was difficult to find similar features to account for geometric corrections. In this work, an image translator, which was built with a DNN (deep neural network) and trained by conditional generative adversarial networks (cGANs) with edge enhancement, was employed to find the corresponding locations between SAR and optical images. When using conventional cGANs, many blurs appear in the translated images and they degrade keypoint-matching accuracy. Therefore, a novel method applying an edge enhancement filter in the cGANs structure was proposed to find the corresponding points between SAR and optical images to accurately register images from different sensors. The results suggested that the proposed method could accurately estimate the corresponding points between SAR and optical images.
• Spectral Angle Mapping and AI Methods Applied in Automatic Identification of Placer Deposit Magnetite Using Multispectral Camera Mounted on UAV

  Brian Bino Sinaice, Narihiro Owada, Hajime Ikeda, Hisatoshi Toriya, Zibisani Bagai, Elisha Shemang, Tsuyoshi Adachi, Youhei Kawamura

  Minerals 12 (2) 2022/02 

  The use of drones in mining environments is one way in which data pertaining to the state of a site in various industries can be remotely collected. This paper proposes a combined system that employs a 6-bands multispectral image capturing camera mounted on an Unmanned Aerial Vehicle (UAV) drone, Spectral Angle Mapping (SAM), as well as Artificial Intelligence (AI). Depth possessing multispectral data were captured at different flight elevations. This was in an attempt to find the best elevation where remote identification of magnetite iron sands via the UAV drone specialized in collecting spectral information at a minimum accuracy of +/− 16 nm was possible. Data were analyzed via SAM to deduce the cosine similarity thresholds at each elevation. Using these thresholds, AI algorithms specialized in classifying imagery data were trained and tested to find the best performing model at classifying magnetite iron sand. Considering the post flight logs, the spatial area coverage of 338 m2, a global classification accuracy of 99.7%, as well the per-class precision of 99.4%, the 20 m flight elevation outputs presented the best performance ratios overall. Thus, the positive outputs of this study suggest viability in a variety of mining and mineral engineering practices.
• Dimensional Reduction of Rock Hyperspectral Signatures and Classiflcation Based on a NCA Method used in developing a UAV Multispectral Imaging System

  Brian Bino Sinaice, Narihiro Owada, Hajime Ikeda, Hisatoshi Toriya, Elisha Shemang, Zibisani Biza Bagai, Shinji Utsuki, Tsuyoshi Adachi, Youhei Kawamura

  International Journal of the Society of Material Engineering for Resources 25 (1) 102 - 108 1347-9725 2022 

  The adoption of hyperspectral imaging has had positive feedback in multiple industries, especially those heavily reliant on the visual analysis of subjects. Reasons for such are primarily due to the high accuracies achievable from processing high dimensional data. Nevertheless, hyperspectral data is said to possess a' dimensionality curse'. This phenomenon, deems it computationally demanding and difflcult to employ in rapid fleld investigations such as the use of drone-mounted spectral cameras to distinguish rocks. To counter this, this study proposes the employment of a method of reducing the number of dimensions used to highlight the most characteristic feature bands referred to as Neighbourhood Component Analysis(NCA). NCA aided in disregarding redundant bands from 204 dimensionalities, to a still highly capable 5 bands dimensionality, which coincides with the current production of 5-band detection drones. To process this data, several machine learning(ML) algorithms were run in order to perform spectral classiflcation of rocks based on the 5 NCA deflned bands. This study's novel flndings show that one is able to acquire with NCA and ML, 5 bands, with a post-optimization average global accuracy of 95.4%. Such capabilities are highly sufflcient considering the magnitude of the dimensionality reduction combined with the potential fleld drone applicability.
• Deep Learning as an Early Detection System for Rotary Percussion Drilling Malfunctions

  Yoshino Kosugi, Hisatoshi Toriya, Mahdi Saadat, Tsuyoshi Adachi, Hajime Ikeda, Youhei Kawamura

  International Journal of the Society of Material Engineering for Resources 25 (2) 205 - 211 1347-9725 2022 

  To mine in the underground, the method of blasting and blast hole drilling methods are mainly, and widely accepted. The hole drilling methods are done with rotary percussion drill. However, there are problems in terms of diffi culty of operating and mining cost resulting from its failure occurs, and thus it is hard for mining companies to fi nd a way of mining underground effi ciently, profi tability, and safely. From this background, it is necessary to build the early detection system for drill bit failure. This system needs the technology of CNN (Convolutional Neural Network Smart Mining, which is the process of using information, autonomy, and technology to improve safety, reduce operating costs, and improve mine site productivity. In this research, drilling vibration from rotary percussion drill is transmitted as acceleration waveform and used as input data for building the system. The data is collected replacing the kinds of diameter of bit or drilling condition. This data is for developing the model introduced CNN to detect the difference between Normal drilling and the other kinds of drilling with something error. For Firstly, batch of waveform data is input model as training data to make the model recognize the data pattern. Secondly, validation process confi rms the correct answer rate against the training data, and then, the test for the model is practiced. Finally, by comparing each accuracy in phase of test from 4 types of models built with diff erent kinds of data and the ideal way of the input waveform data is found.
• Communication Experiment of Wi-Fi Direct for Underground Mine Environment Visualization System

  Hajime Ikeda, Youhei Kawamura, Oluwafemi Kolade, Daniyar Malgazhdar, Mahdi Saadat, Fumiaki Inagaki, Hisatoshi Toriya, Frederick Thomas Cawood

  Lecture Notes in Civil Engineering 228 65 - 76 2366-2557 2022 

  One of the main problems in the modern metal mining sector is the depletion of near-surface deposits, the decline in grades. Available deposits near to surface are available and the focus of the industry is shift to deep underground deposits. However, with increase in mining depth risk of rock falls and rock bursts increases concurrently. In order to solve these problems, “smart mining” technology has been introduced. “Smart mining” is an area that combines ICT and intelligent resource development. We have developed a communication system that plays a fundamental role in this field, and have conducted communication tests. Communication systems in underground mines are essential for better safety and productivity. In this research, wireless sensor networks (WSNs) have been proposed to record and transfer environmental and worker position data. This research proposes a communication system using “Wi-Fi Direct”, in which data loggers and mobile terminals (i.e., smartphones) transfer data between nodes. According to the technology, data is transmitted from a fixed underground base unit to a worker’s mobile terminal. Next, these datasets transferred to a data logger on surface once the worker gets close enough, the data transmitted wirelessly between surface and underground locations. To verify the feasibility of this system, the communication range, transfer speed, and received signal strength indicator (RSSI) in different environments were measured.
• Model Scaling in Smartphone GNSS-Aided Photogrammetry for Fragmentation Size Distribution Estimation

  Zedrick Paul L. Tungol, Hisatoshi Toriya, Narihiro Owada, Itaru Kitahara, Fumiaki Inagaki, Mahdi Saadat, Hyong Doo Jang, Youhei Kawamura

  MINERALS 11 (12) 2021/12 

  Fragmentation size distribution estimation is a critical process in mining operations that employ blasting. In this study, we aim to create a low-cost, efficient system for producing a scaled 3D model without the use of ground truth data, such as GCPs (Ground Control Points), for the purpose of improving fragmentation size distribution measurement using GNSS (Global Navigation Satellite System)-aided photogrammetry. However, the inherent error of GNSS data inhibits a straight-forward application in Structure-from-Motion (SfM). To overcome this, the study proposes that, by increasing the number of photos used in the SfM process, the scale error brought about by the GNSS error will proportionally decrease. Experiments indicated that constraining camera positions to locations, relative or otherwise, improved the accuracy of the generated 3D model. In further experiments, the results showed that the scale error decreased when more images from the same dataset were used. The proposed method is practical and easy to transport as it only requires a smartphone and, optionally, a separate camera. In conclusion, with some modifications to the workflow, technique, and equipment, a muckpile can be accurately recreated in scale in the digital world with the use of positional data.
• Coupling NCA Dimensionality Reduction with Machine Learning in Multispectral Rock Classification Problems

  Brian Bino Sinaice, Narihiro Owada, Mahdi Saadat, Hisatoshi Toriya, Fumiaki Inagaki, Zibisani Bagai, Youhei Kawamura

  MINERALS 11 (8) 2021/08 

  Though multitudes of industries depend on the mining industry for resources, this industry has taken hits in terms of declining mineral ore grades and its current use of traditional, time-consuming and computationally costly rock and mineral identification methods. Therefore, this paper proposes integrating Hyperspectral Imaging, Neighbourhood Component Analysis (NCA) and Machine Learning (ML) as a combined system that can identify rocks and minerals. Modestly put, hyperspectral imaging gathers electromagnetic signatures of the rocks in hundreds of spectral bands. However, this data suffers from what is termed the 'dimensionality curse', which led to our employment of NCA as a dimensionality reduction technique. NCA, in turn, highlights the most discriminant feature bands, number of which being dependent on the intended application(s) of this system. Our envisioned application is rock and mineral classification via unmanned aerial vehicle (UAV) drone technology. In this study, we performed a 204-hyperspectral to 5-band multispectral reduction, because current production drones are limited to five multispectral bands sensors. Based on these bands, we applied ML to identify and classify rocks, thereby proving our hypothesis, reducing computational costs, attaining an ML classification accuracy of 71%, and demonstrating the potential mining industry optimisations attainable through this integrated system.
• Tourist Participation in the Preservation of World Heritage - A Study at in Cambodia -

  Fumiya Kimura, Yutaka Ito, Toshiya Matsui, Hidehiko Shishido, Itaru Kitahara, Youhei Kawamura, Atsuyuki Morishima

  JOURNAL OF CULTURAL HERITAGE 50 163 - 170 1296-2074 2021/07 

  World Heritage Sites (WHSs) face several problems, such as increased maintenance costs, difficulties in checking protection conditions, and graffiti destruction by tourists. Hence, constructing a new system that can effectively lighten the burden of maintenance expenditures is necessary. Presently, a new preservation system that leverages Information and Communication Technology, 3D Restoration Technology by photographic data collection, and artificial intelligence and that involves tourists' participation has been developed. This paper aims to introduce the new preservation system, investigate the possibility of tourists cooperating with the system free of charge, and introduce the details and results of a choice experiment conducted on tourists at Bayon Temple in Cambodia. Analysis results showed that approximately 50% of respondents would be willing to cooperate free of charge, and statistical significance for certain attributes and interactions. The analysis indicated that providing appropriate incentives to tourists who have specific individual characteristics would help promote the use of the preservation system. (c) 2021 Elsevier Masson SAS. All rights reserved.
• Investigating asperity damage of natural rock joints in polycrystalline rocks under confining pressure using grain-based model

  Mahdi Saadat, Abbas Taheri, Youhei Kawamura

  COMPUTERS AND GEOTECHNICS 135 104144 - 104144 0266-352X 2021/07 [Refereed][Not invited]
   

  A cohesive grain-based model (GBM) was employed to investigate the asperity damage response of jointed Aue granite under confined compression. The cohesive GBM was able to characterise both inter- and intra-grain contacts in distinct element method (DEM). We calibrated the model against the laboratory data, including confined and unconfined compression tests as well as Brazilian tensile test of Aue granite. We generated synthetic Aue granite specimens, including three different rock joint profiles with various joint roughness coefficients (JRC) from smooth to very rough (i.e. 4.6, 10.2, and 17.5). We conducted confined compression tests on the synthetic specimens under 2, 5, 10, and 40 MPa of confining pressures. The numerical results revealed that at high confining pressure (i.e. 40 MPa), the rock joint profile had a negligible influence of the damage response of the specimen, and only contributed to the reduction of strength. For the other numerical experiments, the intensity of asperity damage caused by grain crushing was more pronounced when the confining pressure was high. We concluded that the cohesive GBM framework has the potential to be used as a virtual laboratory for investigating the shear behaviour of jointed granitic rocks, which is challenging to be studied in the laboratory.
• Incorporating asperity strength into rock joint constitutive model for approximating asperity damage: An insight from DEM modelling

  Mahdi Saadat, Abbas Taheri, Youhei Kawamura

  ENGINEERING FRACTURE MECHANICS 248 107744 - 107744 0013-7944 2021/05 [Refereed][Not invited]
   

  This paper presents a DEM experiment for developing a rock joint constitutive model that is able to consider lab-scale geometrical parameters of waviness and unevenness. We carried out a systematic parametric study using DEM framework to investigate the influence of asperity area and asperity angle on the peak shear strength and peak dilation angle. Based on the insights obtained from numerical outputs, we defined an asperity strength parameter that was incorporated into the failure criterion of the rock joint model. We defined an asperity damage function to characterise the degradation of asperity strength parameter. Besides, we developed a separate damage function to consider the deterioration of frictional components of rock joints. Also, we augmented the dilative response of the rock joint model by defining a new dilation predictor that mimics the normal displacement with respect to the progressive shear displacement of the rock joint. The damage function was linked to plastic displacement of rock joint in all damage functions. We compared the model outputs with the results of experimental direct shear tests conducted on natural rock joints and observed a good agreement.
• Classification of Arsenic Bearing Minerals Using Hyperspectral Imaging and Deep Learning for Mineral Processing

  OKADA Natsuo, MAEKAWA Yohei, OWADA Narihiro, HAGA Kazutoshi, SHIBAYAMA Atsushi, KAWAMURA Youhei

  Journal of MMIJ 一般社団法人 資源・素材学会 137 (1) 1 - 9 1881-6118 2021/01/31 [Not refereed]
   

  Currently, there have been issues concerning the depletion and scarcity of mineral resources. This is mostly due to the excavation of high grade minerals having already occurred years and years ago, hence forcing the mining industry to opt for the production and optimization of lower grade minerals. This however brings about a plethora of problems, many of which economic, stemming from the purification of those low grade minerals in various stages required for mineral processing. In order to reduce costs and aid in the optimization of the mining stream, this study, introduces an automatic mineral identification system which combines the predictive abilities of deep learning with the excellent resolution of hyperspectral imaging, for pre-stage of mineral processing. These technologies were used to identify and classify high grade arsenic (As) bearing minerals from their low grade mineral counterparts non-destructively. Most of this ability to perform such tasks comes from the highly versatile machine learning model which employs deep learning as a means to classify minerals for mineral processing. Experimental results supported this statement as the model was able to achieve an over 90% accuracy in the prediction of As-bearing minerals, hence, one could conclude that this system has the potential to be employed in the mining industry as it achieves modern day system requirements such as high accuracy, speed, economic, userfriendly and automatic mineral identification.
• Application of entropy method for estimating factor weights in mining-method selection for development of novel mining-method selection system

  Elsa Pansilvania Andre Manjate, Mahdi Saadat, Hisatoshi Toriya, Fumiaki Inagaki, Youhei Kawamura

  Journal of Sustainable Mining 20 (4) 296 - 308 2543-4950 2021 

  Mining-method selection (MMS) is one of the most critical and complex decision-making processes in mine planning. Therefore, it has been a subject of several studies for many years culminating with the development of different systems. However, there is still more to be done to improve and/or create more efficient systems and deal with the complexity caused by many influencing factors. This study introduces the application of the entropy method for feature selection, i.e., select the most critical factors in MMS. The entropy method is applied to assess the relative importance of the factors influencing MMS by estimating their objective weights to then select the most critical. Based on the results, ore strength, host-rock strength, thickness, shape, dip, ore uniformity, mining costs, and dilution were identified as the most critical factors. This study adopts the entropy method in the data preparation step (i.e., feature selection) for developing a novel-MMS system that employs recommendation system technologies. The most critical factors will be used as main variables to create the dataset to serve as a basis for developing the model for the novel-MMS system. This study is a key step to optimize the performance of the model.
• Mutual superimposing of SAR and ground-level shooting images mediated by intermediate multi-altitude images.

  Hisatoshi Toriya, Narihiro Owada, Mahdi Saadat, Fumiaki Inagaki, Ashraf Dewan, Youhei Kawamura, Itaru Kitahara

  Array 12 100102 - 100102 2021
• Hazard mapping of ground subsidence in east area of Sapporo using frequency ratio model and GIS

  Taeyoo Na, Youhei Kawamura, Seong-seung Kang, Shinji Utsuki

  GEOMATICS NATURAL HAZARDS & RISK 12 (1) 347 - 362 1947-5705 2021/01/01 [Refereed][Not invited]
   

  As an earthquake occurred in Iburi subprefecture, Japan on September 2018, Sapporo has also been damaged by ground subsidence. Ground subsidence can occur in various area, especially in urban areas causing considerable damage to human lives and properties. Currently, ground subsidence is one of the most important problems all over the world. However, quantitative research about ground subsidence due to earthquake that particularly occurred in urban area was not well studied. To prevent and minimize critical damage caused by subsidence, this study aims to construct hazard map to predict susceptible subsidence place in East area of Sapporo, using geographic information system (GIS) and frequency ratio (FR) model. To determine major factors related to ground subsidence, spatial databases were constructed from geological map, slope data, land use map, borehole data, precipitation data, railroad and subway line data and earthquake information data. Weight of each factors were estimated by FR model to analyze degree of subsidence hazard and construct subsidence hazard map. Constructed subsidence susceptibility map was compared with reported actual ground subsidence area for verification and showed prediction accuracy of 85.17%. This result showed sufficient possibility for reliable susceptibility mapping of ground subsidence using GIS and FR model.
• Automated Identification of Mineral Types and Grain Size Using Hyperspectral Imaging and Deep Learning for Mineral Processing

  Natsuo Okada, Yohei Maekawa, Narihiro Owada, Kazutoshi Haga, Atsushi Shibayama, Youhei Kawamura

  MINERALS 10 (9) 1 - 22 2020/09 

  In mining operations, an ore is separated into its constituents through mineral processing methods, such as flotation. Identifying the type of minerals contained in the ore in advance aids greatly in performing faster and more efficient mineral processing. The human eye can recognize visual information in three wavelength regions: red, green, and blue. With hyperspectral imaging, high resolution spectral data that contains information from the visible light wavelength region to the near infrared region can be obtained. Using deep learning, the features of the hyperspectral data can be extracted and learned, and the spectral pattern that is unique to each mineral can be identified and analyzed. In this paper, we propose an automatic mineral identification system that can identify mineral types before the mineral processing stage by combining hyperspectral imaging and deep learning. By using this technique, it is possible to quickly identify the types of minerals contained in rocks using a non-destructive method. As a result of experimentation, the identification accuracy of the minerals that underwent deep learning on the red, green, and blue (RGB) image of the mineral was approximately 30%, while the result of the hyperspectral data analysis using deep learning identified the mineral species with a high accuracy of over 90%.
• Enhancement of bitumen recovery from the oil sand in an alkaline solution using ultrasound irradiation and carbon dioxide

  Hirokazu Okawa, Tomonao Saito, Shohei Yasuda, Youhei Kawamura, Takahiro Kato, Katsuyasu Sugawara, Tayfun Babadagli

  JAPANESE JOURNAL OF APPLIED PHYSICS 59 (SK) 0021-4922 2020/07/01 [Refereed][Not invited]
   

  Herein, we demonstrated the enhancement of bitumen recovery from the oil sand in a concentrated alkaline solution using ultrasound irradiation and carbon dioxide. The alkaline solution allowed the separation of bitumen and sand; however, it was difficult to collect bitumen via aeration. CO exhibited a high contact angle for bitumen even at a high pH. Therefore, we attempted to use CO for bitumen recovery under ultrasound irradiation, increasing the number of collisions between bitumen and the CO bubbles; thus, the bitumen recovery ratio exhibited a high value of approximately 70% even at a low CO injection rate of 20 ml min 2 2 2 2 -1
• Accurate Overlapping Method of Ultra-Long Interval Time-Lapse Images for World Heritage Site Investigation

  Hidehiko Shishido, Emi Kawasaki, Youhei Kawamura, Toshiya Matsui, Itaru Kitahara

  ACM JOURNAL ON COMPUTING AND CULTURAL HERITAGE 13 (2) 10 - 18 1556-4673 2020/06 

  In this article, a method is proposed to accurately overlap multiple high-quality images with different shooting positions and intervals by combining corresponding point information between images and 3D shape information. In the proposed method, the correct feature matching of images obtained by rendering the 3D model of the subject is used. In this research, the subjects were the pillars of the Angkor Thom Bayon Temple and the epilithic microorganisms adhering to and eroding their surfaces. Synthetic transformation of a homography utilizing the correct matches is employed to overlap the target images. When overlapping different background images using the conventional method, estimation of the homography matrix becomes difficult owing to incorrect matches; thus, high-quality overlapping images cannot be obtained. The objective of this research was to realize the overlapping image process even under conditions that cause incorrect feature matches, such as differences in background and illumination. In this study, the damaged parts of the pillar surfaces were visualized using the proposed method. Based on the results of an experiment comparing the proposed method with an existing state-of-the-art method, the effectiveness and higher accuracy of the proposed method were verified. The findings of this research contribute to Angkor Thom Bayon Temple preservation, including a preservation project that the present authors are organizing for this culturally and historically valuable United Nations Educational, Scientific and Cultural Organization World Heritage site.
• Development and Validation of Virtual Reality Application in Mining Education

  Yutaka ITO, Masato TAKEUCHI, Shuto MIKAMI, Youhei KAWAMURA

  Journal of MMIJ 136 (5) 33 - 39 1881-6118 2020/05/31 [Refereed][Not invited]
  
• Development of 3D rock fragmentation measurement system using photogrammetry

  Hyongdoo Jang, Itaru Kitahara, Youhei Kawamura, Yasunori Endo, Erkan Topal, Ryo Degawa, Samson Mazara

  INTERNATIONAL JOURNAL OF MINING RECLAMATION AND ENVIRONMENT 34 (4) 294 - 305 1748-0930 2020/04 [Refereed][Not invited]
   

  Run-of-mine fragmentation is an important aspect of mine productivity optimisation, as it affects all mine-to-mill processes. In this study, a 3D rock fragmentation measurement (3DFM) system is proposed that can surmount the limitations of conventional 2D photo-based rock fragmentation measurement methods. To validate the proposed 3DFM performance, a laboratory-based comparison study was conducted using 100 randomly collected rock fragments. Conventional method exhibits relatively low and diffused results than the 3DFM. The proposed 3DFM can be considered as a new particle size distribution measurement method that should efficiently aid in improving mine productivity.
• University Students' Preferences for Labour Conditions at a Mining Site: Evidence from Two Australian Universities

  Yutaka Ito, Shuto Mikami, Hyongdoo Jang, Abbas Taheri, Kenta Tanaka, Youhei Kawamura

  RESOURCES-BASEL 9 (3) 2020/03/01 

  The mining industry makes up a large portion of the gross domestic product (GDP) in Australia, although securing human resources remains a problem in that field. The aim of this paper is to identify Australian university mining students' preferences, considering it as potential employees' preferences, for labour conditions at mining sites by means of a discrete choice experiment to promote efficient improvements in labour conditions in the mining industry. The data of 93 respondents analysed in this paper was collected by survey carried out in two universities in Australia. The result of the study showed that students have preferences on several factors such as wage, fatality rate, working position, commuting style, and company. Students having specific sociodemographic characters were found to show specific preferences on labour conditions. The results of this study indicate the potential average of appropriate monetary compensation for each factor.
• Application of deep learning approaches in igneous rock hyperspectral imaging

  Brian Bino Sinaice, Youhei Kawamura, Jaewon Kim, Natsuo Okada, Itaru Kitahara, Hyongdoo Jang

  Springer Series in Geomechanics and Geoengineering 228 - 235 1866-8755 2020 

  Hyperspectral imaging has been applied in remote sensing amongst other disciplines, success in these has triggered its extensive use. Hence, it comes as no surprise that we took advantage of this technology by conducting a study aimed at the spectral analysis of several igneous rocks, and to deduce the spectral signatures of each rock unit using neural networks. Through visual observations and comparisons of these spectral signatures, parameters such as band curvature(shape), tilt(position) and strength were used for lithological discrimination. Even with this said, there often exists similarities in rocks, which are rather difficult to differentiate by means of visual or graphical analysis. However, with numerous technologies making new waves in today’s era and artificial intelligence (AI) being at the forefront of these developments, it was best fitting to employ deep learning, often referred to as a subset of AI; to train/learn from these hyperspectral signatures with a goal aimed at classifying these rocks. Deep learning has networks such as the convolution neural network (CNN), which has algorithms that excel in feature representation from visual imagery; taking into account that the more data is fed into the training process and later used as a database for further training, the higher the future prediction accuracy. Gathered outcomes from the CNN show exceptionally high prediction accuracy capabilities of 96%; suggesting viable field and laboratory usage of these systems as a unit for mining and rock engineering applications.
• Development of an underground in-situ stress monitoring system for mining safety using multi sensor cell and wi-fi direct technology

  Hajime Ikeda, Youhei Kawamura, Hyongdoo Jang, Nur Ellisha Binti Mokhtar, Jun Yokokura, Zedrick Paul L. Tungol

  Springer Series in Geomechanics and Geoengineering 236 - 244 1866-8755 2020 

  The increasing global demand for minerals contributes to the necessity of mineral extraction at greater depths. However, the increase of rock in-situ stress with depth leads to higher risk and increasingly dangerous working conditions faced by mining workers. The presence of shafts, tunnels and other excavations necessary in mine expansions further increase the complexity of underground mines. This complexity of underground stress conditions increases the importance of monitoring and analysis of underground strata conditions, as early detection is crucial in the prevention of rock failure and the occurrence of fatal accidents. A better comprehension of the underground stress conditions in a mine is vital in considering mine design and supports that need to be installed. The development of an efficient monitoring system that can obtain and transmit data is necessary. This paper suggests the utilisation of a multi sensor cell that combines the functions of an accelerometer, gyroscope and a magnetometer, as well as strain gauge displacements to continuously measure the stress conditions of bedrock. The obtained data is then conveyed to the surface using a Wi-Fi Direct communication system and analysed to comprehend the changes in the underground stress conditions. The latter part of this paper also describes the experiments conducted to verify the ability of the proposed monitoring system.
• An automated underground space monitoring and communication system based on wireless sensor networks

  Mohammad Ali Moridi, Mostafa Sharifzadeh, Hyongdoo Jang, Youhei Kawamura

  Springer Series in Geomechanics and Geoengineering 255 - 261 1866-8755 2020 

  In the challenging environment and Cutting-edge technology in mining industry, reliable and effective communication is a high-stake issue, along with the objectives of safe and efficient underground mining operations. Automation through remote and automatic systems has delivered improvements in workplace health and safety for employees, operational management, energy and cost-effectiveness, and real-time response to events. In this context, Wireless Sensor Networks (WSNs) have been widely employed in underground monitoring and communication systems for the purpose of environmental monitoring, the positioning of workers and equipment, operational monitoring and communication system. Considering the capabilities of WSNs, a ZigBee network is adopted in this study. The aim of this study is to propose a reliable and effective monitoring and communication system in underground environments, using WSN nodes were developed to sense environmental attributes and texting emergency messages. A trigger action plan for monitored attributes above normal and threshold value limits is programmed in the surface GIS management server. The system will provide multi-users surface operation and 3D visualization for realistic understanding of underground environment and miners’ conditions.
• Illumination of contributing parameters of uneven break in narrow vein mine

  Hyongdoo Jang, Sina Taheri, Erkan Topal, Youhei Kawamura

  Springer Series in Geomechanics and Geoengineering 457 - 466 1866-8755 2020 

  One of the principal challenge facing the stope production in underground mining is the overbreak and underbreak (UB: uneven break). Although the UB features a critical economic fallout to the entire mining process, it is much inevitable and usually left as an unpredictable phenomenon in underground mines. The complex mechanism of UB must be examined to minimize the UB phenomenon. In this study, the contribution of ten primary UB causative parameters is scrutinized investigating a published UB prediction ANN model. The inputs (UB causative factors) contributions to the output (percentage of UB) of the ANN model were analyzed using Profile methodology (PM). The results PM revealed the essential importance of geological parameters to UB phenomenon as the calculated contributions of adjusted Q-rate (GAQ) and average horizontal to vertical stress ratio (GSK) are 20.48% and 18.12% respectively. Also, the trends of the other eight UB causative factors were investigated. The findings of this study can be used as a reference in stope design and reconciliation processes to maximize the productivity of the underground mine.
• Clustering method of 3D point cloud of muck-pile based on connectivity of adjacent surface

  Hidehiko Shishido, Zha Wanzhi, Hyongdoo Jang, Youhei Kawamura, Yoshinari Kameda, Itaru Kitahara

  2019 IEEE 8th Global Conference on Consumer Electronics, GCCE 2019 770 - 774 2019/10 

  This paper proposes a method to measure the fragmentation distribution of a pile of rocks (muck-pile) using image-based 3D reconstruction. One of the most important aspects of mine-blasting is appropriate rock fragmentation to optimize the cost of the blasting operation. The conventional method of measuring fragmentation distribution is based on 2D image processing including segmentation of muck-pile regions into rock clusters. However, in the 2D method, the measurement accuracy is limited. To accurately measure rock fragmentation distribution, we reconstructed a 3D model of a muck-pile from multi-view images and segment the 3D model based on rock-features such as color, normal vector, distance and adjacent angles of surface planes. As a result, the size of each rock was calculated by fitting a bounding box. Based on experimental evaluations, it was confirmed that the accuracy of the proposed method is higher than that of previous methods.
• An empirical approach of overbreak resistance factor for tunnel blasting

  Hyongdoo Jang, Youhei Kawamura, Utsuki Shinji

  TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 92 0886-7798 2019/10 [Refereed][Not invited]
   

  The assessment of overbreak is proposed by means of a novel empirical approach; the ‘overbreak resistance factor’ (ORF), to predict and manage the overbreak phenomenon in tunnel drill-and-blast operations. The proposed ORF is formulated by analysing the relationship between uncontrollable parameters of the overbreak phenomenon, i.e., geological parameters, and the corresponding overbreak measurements. Ninety data sets were collected from the Shin-Hakoishi Tunnel operation in Japan. Initially, an identical weight was applied to all geological parameters to generate ORF subfactors. The contribution of these subfactors to the measured overbreak was analysed through the use of five overbreak prediction artificial neuron network (ANN) models. A sensitivity analysis was conducted on the ANN models to reveal the contributions of input factors to measured overbreak. The discontinuities factors demonstrated the highest influence on overbreak with an overall sensitivity of 55.20%, whereas the strength factors, the weathering factors and the face condition factors showed less sensitivity, at 27.18%, 9.43%, and 8.18% respectively. The sensitivity analysis results were applied back to the initial unweighted data sets to generate a weighted record of subfactors. The ORF values showed a clear inverse proportional relation to the measured overbreak values, through linear regression analysis. Consequently, a five-step ORF prediction chart was developed, which can be directly applied to estimate overbreak in any drill-and-blast tunnel project.
• Overlapping of time sequence change images of lichens in Angkor ruins

  宍戸, 英彦, 河﨑, 衣美, 川村, 洋平, 松井, 敏也, 北原, 格

  月刊考古学ジャーナル ニューサイエンス社 (730) 29 - 33 0454-1634 2019/09 [Not refereed][Not invited]
  
• Development of Angkor Bayon Temple Monitoring System for Preventive Preservation Using ICT

  池田, 啓, 川村, 洋平, 横倉, 潤, 宍戸, 英彦, 河﨑, 衣美, 伊藤, 豊, 北原 格, 丸太, 寛之, 里, 知樹, 松井, 敏也

  The 36th Annual Meeting of the Japan Society for Scientific Studies on Cultural Property Abstracts 日本文化財科学会第36回事務局 20 - 21 2019/06 [Not refereed][Not invited]
  
• Implementation and Verification of a Wi-Fi Ad Hoc Communication System in an Underground Mine Environment

  H. Ikeda, Y. Kawamura, Z. P.L. Tungol, M. A. Moridi, H. Jang

  Journal of Mining Science 55 (3) 505 - 514 1062-7391 2019/05/01 

  Wireless sensor networks WI-Fi ad hoc have been proposed information transmission between data loggers and mobile station (smartphones). The wireless data transmission follows from an underground station to a worker’s smartphone and, then, after the worker has left the mine, to a data logger on the surface. The serviceability of this system was tested by measurement of communication quality indexes in various environments. The tests show that wireless communication between a stationary point and a mobile devise is possible at transfer speeds up to 2 MB/s with a packet error rate (PER) below 25% either at a maximum distance of 110 m in a straight path or at a distance of 20 m in case of a corner or turn of the path. The proposed system allows the transmission of 39.6–79.2 MB of monitoring data to a worker moving at 20 km/h.
• Development of wireless sensor networks for underground communication and monitoring systems (the cases of underground mine environments)

  Mohammad Ali Moridi, Mostafa Sharifzadeh, Youhei Kawamura, Hyong Doo Jang

  TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 73 127 - 138 0886-7798 2018/03 [Refereed][Not invited]
   

  The challenges of maintaining safe workplaces and improving operations and services in underground mines are unique. These have largely been mitigated by implementing new technology of wireless sensor networks (WSNs) in the last few years. Establishment and development of a reliable monitoring and communication network through such hostile environments are still major concerns. In this study, a more comprehensive monitoring and communication system for underground mine environments using ZigBee network are developed. To this regard, experiments with real systems and prototypes are applied. The controllable and uncontrollable parameters of both underground environment and network for the establishment of ZigBee network are also assessed. Then, a practical method to design a model of an underground mine monitoring and communication system is proposed. This model was verified by testing system functions and applications for example, temperature, humidity and illumination readings, text messaging, and controlling ventilation fans throughout an underground mine in Western Australia. The monitoring and communication systems operated successfully and it demonstrated the reliable outcomes of their function and application for underground mines.
• クラウドソーシングと３次元復技術による世界遺産の予防的保存

  河崎 衣美, 伊藤 豊, 川村 洋平, 松井 敏也, 北原 格

  信学技報 2 77 - 82 2018 [Refereed]
  
• Performance analysis of ZigBee network topologies for underground space monitoring and communication systems

  Mohammad Ali Moridi, Youhei Kawamura, Mostafa Sharifzadeh, Emmanuel Knox Chanda, Markus Wagner, Hirokazu Okawa

  TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 71 201 - 209 0886-7798 2018/01 [Refereed][Not invited]
   

  The advancement in tunnelling and underground space technologies and the need for large scale monitoring and communication systems for safe and efficient operations has triggered the era of wireless sensor networks (WSNs). The progress of WSNs have been associated with the innovation of sensor nodes with the more significant features of smaller size, more cost-effectiveness, lower latency and powerful antenna coverage. The sensor nodes arrangement in dense industrial WSNs is one of the crucial issues for a better quality of service and a reliable message transmission through the network. In this study, we investigate various sensor node arrangements of ZigBee networks for underground space monitoring and communication systems. The performance of ZigBee topologies are analysed in 12, 20, 30, 40 and 50-node scenarios for stationary node deployment in underground environments. The metrics used for the performance evaluation include throughput, packet delivery ratio (PDR), end-to-end delay, energy consumption and packet delivery security. The results evaluation confirms the mesh topology is prioritised in WSNs design considering higher throughput, packet delivery ratio and network security, while the cluster-tree topology is preferred in case of lower end-to-end delay and lower energy consumption. The analyses show that the mesh topology creates a more reliable monitoring and communication network with an adequate quality of service in underground spaces and tunnels. Therefore, greater end-to-end delay and energy consumption could not be major concerns for the mesh topology in underground mine applications based on the acceptable data latency and using mine power.
• Time-Lapse Image Generation using Image-Based Modeling by Crowdsourcing

  Hidehiko Shishido, Emi Kawasaki, Yutaka Ito, Youhei Kawamura, Toshiya Matsui, Itaru Kitahara

  2018 IEEE INTERNATIONAL CONFERENCE ON BIG DATA (BIG DATA) 3541 - 3542 2639-1589 2018 [Refereed][Not invited]
   

  In recent years, the pillars of the World Heritage Angkor Thom Bayon temple have become a problem of deterioration due to moss breeding. We aim to generate an image to support observation of moss breeding on a pillar. Even under environment that prevent image processing, we can achieve accurate overlay processing by combining corresponding points between images and 3D shapes. In order to generate the timelapse image of the observation target, many accurate images of different capturing timings are necessary. We are going to use a lot of images collected by crowdsourcing for time lapse images. In this research, we use two crowdsourcing models with the »capturing image of the target region» and the »classification of the captured images» as the micro task. Therefore, image acquisition using crowdsourcing and generation of time lapse image are looped. Time lapse image will be more accurate by repeating this flow.
• Comparison of Rock Fragmentation Measurement Systems with 3D System using Photogrammetry Technology

  Kitahara, Itaru, Kawamura, Youhei, Topal, Erkan, Endo, Yasunori, Degawa, Ryo, Jang, Hyongdoo

  The 2017 World Congress on Advances in Structural Engineering and Mechanics 2017/08 [Refereed][Not invited]
  
• Utilization of ultrasonic atomization for dust control in underground mining

  Hirokazu Okawa, Kentaro Nishi, Youhei Kawamura, Takahiro Kato, Katsuyasu Sugawara

  JAPANESE JOURNAL OF APPLIED PHYSICS 56 (7) 0021-4922 2017/07 [Refereed][Not invited]
   

  This study examined dust suppression using water particles generated by ultrasonic atomization (2.4 MHz) at low temperature (10 °C). Green tuff (4 μm), green tuff (6 μm), kaolin, and silica were used as dust samples. Even though ultrasonic atomization makes fine water particles, raising relative air humidity immediately was difficult at low temperature. However, remaining water particles that did not change to water vapor contributed to suppression of dust dispersion. Additionally, the effect of water vapor amount (absolute humidity) and water particles generated by ultrasonic atomization on the amount of dust dispersion was investigated using experimental data at temperatures of 10, 20, and 30 °C. Utilization of ultrasound atomization at low temperature has the advantages of low humidity increments in the working space and water particles remaining stable even with low relative air humidity.
• Proactive Preservation of World Heritage by Crowdsourcing and 3D Reconstruction Technology

  Hidehiko Shishido, Yutaka Ito, Youhei Kawamura, Toshiya Matsui, Atsuyuki Morishima, Itaru Kitahara

  2017 IEEE INTERNATIONAL CONFERENCE ON BIG DATA (BIG DATA) 2018-January 4426 - 4428 2639-1589 2017/07/01 [Refereed][Not invited]
   

  Since over one million tourists annually visit the Angkor ruins, the effect on the buildings from the vibrations caused by these tourists is a huge problem for maintaining them. Such organisms as bryophytes, which adhere to the surface of the stones of the ruins, is another factor that damages them. Using crowdsourcing and 3D reconstruction technology, we are organizing a proactive preservation project for the Angkor Thom Bayon Temple, which is a world cultural heritage site. We evaluated its damaged parts and visualized the damaged state.
• 粒度分布推定のための発破ずり３次元モデルの生成手法

  出川, 諒, 亀田, 能成, 川村, 洋平, Jang, Hyongdoo, 北原, 格

  電子情報通信学会 技術研究報告MVE 電子情報通信学会 116 (496) 197 - 202 2017/02 [Not refereed][Not invited]
  
• クラウドソーシングと３次元復技術による世界遺産の予防的保存

  河崎 衣美, 伊藤 豊, 川村 洋平, 松井 敏也, 北原 格

  IEICE Technical Report PRMU2017 77 - 82 2017 [Refereed]
  
• Illumination of parameter contributions on uneven break phenomenon in underground stoping mines

  Jang Hyongdoo, Topal Erkan, Kawamura Youhei

  INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY 26 (6) 1095 - 1100 2095-2686 2016/11/01 [Refereed][Not invited]
   

  One of the most serious conundrum facing the stope production in underground metalliferous mining is uneven break (UB: unplanned dilution and ore-loss). Although the UB has a huge economic fallout to the entire mining process, it is practically unavoidable due to the complex causing mechanism. In this study, the contribution of ten major UB causative parameters has been scrutinised based on a published UB predicting artificial neuron network (ANN) model to put UB under the engineering management. Two typical ANN sensitivity analysis methods, i.e., connection weight algorithm (CWA) and profile method (PM) have been applied. As a result of CWA and PM applications, adjusted Q rate (AQ) revealed as the most influential parameter to UB with contribution of 22.40% in CWA and 20.48% in PM respectively. The findings of this study can be used as an important reference in stope design, production, and reconciliation stages on underground stoping mine.
• Development of a Landslide Observation System Using ZigBee Wireless Communication Technology

  Y. Kawamura, H. Jang, K. Ohta, Y. Inagaki

  Geotechnical Special Publication 2016-January (269 GSP) 542 - 550 0895-0563 2016 [Refereed][Not invited]
   

  Extensive area of Japan is subjected to threats of potential landslides as roughly 70 percent of Japan consists of a steep mountainous terrain and moreover numerous artificial hill slopes are developed in residential areas. While various types of structural counter measures have been developed and successfully implemented in Japan, significant numbers of areas remain unprotected. Hence, non-structural measures, such as hazard maps and early warning systems, are required to minimize risks. One of the key technologies of the early warning system is the automatic detection system for landslides. In this research, we are developing an automatic detection system for landslides using ZigBee wireless communication technology. A general ZigBee-compliant platform made by Hitachi Co. Ltd. was customized and used in the constructing the wireless landslide detection system. The developed system monitors various environmental data, such as 3-axes acceleration, temperature, humidity, and illumination intensity. It was verified that all measured parameters except humidity were measured properly at an actual slope site with the proposed system.
• 3D Model Reconstruction of Rocks on a Slope for Simulating a Rock Fall

  Itaru Kitahra, Shogo Atsumi, Ryo Degawa, Youhei Kawamura, Hyongdoo Jang, Yuichi Ohta

  Geotechnical Special Publication 2016- (269) 508 - 517 0895-0563 2016 [Refereed][Not invited]
   

  For reducing damage of rock fall, it is important to estimate the route, leap height and velocity of the rock. Although research about estimation of falling motion of rocks are actively conducted, there are still unsolved issues, since rock fall is a complex phenomenon affected by position, size, or shape of rocks and angle of slope. This paper proposes a method of rock fall simulation using a 3D model of rock and slope reconstructed by merging multiple-view images. The proposed method requires only a mobile camera to generate a 3D model, so that more practical rock fall simulation can be realized. In addition, reconstructing textured 3D model makes inspectors visually confirm how the rock falls on the slope. Due to the difficulty capturing multiple images of both of rocks and a slope at a same time, rocks and a slope are individually captured, and then, they are merged in the post process. There are two problems to be solved for merging them accurately. One is the significant difference in their spatial resolution the other is the difference in the appearance caused by perspective projection. We conduct an experiments using multiple images of rocks and slopes captured at actual landslide site.
• An Automated Sensing System for Steel Bridge Inspection Using GMR Sensor Array and Magnetic Wheels of Climbing Robot

  Rui Wang, Youhei Kawamura

  JOURNAL OF SENSORS 2016 8121678 - 15 1687-725X 2016 [Refereed][Not invited]
   

  Corrosion is one of the main causes of deterioration of steel bridges. It may cause metal loss and fatigue cracks in the steel components, which would lead to the collapse of steel bridges. This paper presents an automated sensing system to detect corrosion, crack, and other kinds of defects using a GMR (Giant Magnetoresistance) sensor array. Defects will change the relative permeability and electrical conductivity of the material. As a result, magnetic field density generated by ferromagnetic material and the magnetic wheels will be changed. The defects are able to be detected by using GMR sensor array to measure the changes of magnetic flux density. In this study, magnetic wheels are used not only as the adhesion device of the robot, but also as an excitation source to provide the exciting magnetic field for the sensing system. Furthermore, compared to the eddy current method and the MFL (magnetic flux leakage) method, this sensing system suppresses the noise from lift-off value fluctuation by measuring the vertical component of induced magnetic field that is perpendicular to the surface of the specimen in the corrosion inspection. Simulations and experimental results validated the feasibility of the system for the automated defect inspection.
• Development of climbing robot for steel bridge inspection

  Rui Wang, Youhei Kawamura

  INDUSTRIAL ROBOT-THE INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH AND APPLICATION 43 (4) 429 - 447 0143-991X 2016 [Refereed][Not invited]
   

  Purpose - The purpose of this paper is to present a design of climbing robot with magnetic wheels which can move on the surface of steel bridge. The locomotion concept is based on adapted lightweight magnetic wheel units with relatively high attractive force and friction force. Design/methodology/approach - The robot has the main advantages of being compact (352 - 215 - 155 mm), lightweight (2.3 kg without battery) and simple mechanical structure. It is not only able to climb vertical walls and follow circumferential paths, but also able to pass complex obstacles such as bolts, steps, convex and concave corners with almost any inclination regarding gravity. By using a servo as a compliant joint, the wheel base can be changed to enable the robot to overcome convex corners. Findings - The experiment results show that the climbing robot has a good performance on locomotion, and it is successful in negotiating the complex obstacles. On the other hand, the limitations in locomotion of the robot are also presented. Originality/value - Compared with the past researches, the robot shows good performance on overcoming complex obstacles such as concave corners, convex corners, bolts and steps on the steel bridge. Magnetic wheel with the characterization of compact size and lightweight is able to provide bigger adhesion force and friction coefficient.
• Study on the Conservation Materials for Bas Relief of Bayon

  跡見,洋祐, 松井,敏也, 川村 洋平

  Annual Technical Report on the Survey of Angkor Monument 2014-2015 日本国政府アンコール遺跡救済チーム 161 - 162 2015/12 [Not refereed][Not invited]
  
• A Multimedia Data Visualization Based on Ad Hoc Communication Networks and Its Application to Disaster Management

  Youhei Kawamura, Markus Wagner, Hyongdoo Jang, Hajime Nobuhara, Takeshi Shibuya, Itaru Kitahara, Ashraf M. Dewan, Bert Veenendaal

  ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION 4 (4) 2004 - 2018 2220-9964 2015/12 [Refereed][Not invited]
   

  After massive earthquakes and other large-scale disasters, existing communication infrastructure may become unavailable and, therefore, it can be quite difficult for relief organizations to fully grasp the impact of the disaster on the affected region. Consequently, this will be the cause of delays to offer the strategic assistance, and to provide water and food, etc. In order to solve the problem of re-establishing communication infrastructure to allow for information gathering, we developed an ad hoc mobile communications network for disaster-struck areas using ZigBee. As the communication speed of ZigBee is low, we propose a problem-specific image compression method for the multimedia data visualization. By using the proposed method combined with GPS information, it is possible to quickly grasp the damage situation in the region. Through our communication experiments in Tsukuba City, Japan we confirm the effectiveness of our system as a disaster information gathering and management system.
• Development of underground mine monitoring and communication system integrated ZigBee and GIS

  Moridi Mohammad Ali, Kawamura Youhei, Sharifzadeh Mostafa, Chanda Emmanuel Knox, Wagner Markus, Jang Hyongdoo, Okawa Hirokazu

  INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY 25 (5) 811 - 818 2095-2686 2015/09/01 [Refereed][Not invited]
   

  An automated underground mine monitoring and communication system based on the integration of new technologies is introduced to promote safety and health, operational management and cost-effectiveness. The proposed system integration considering Wireless Sensor Network (WSN) assisted Geographic Information System (GIS) enables to monitor and control underground mining applications from surface office. Based on the capabilities of WSNs, ZigBee network is adapted for near real-time monitoring, ventilation system control and emergency communication in underground mine. ZigBee nodes were developed to sense environmental attributes such as temperature, humidity and gases concentration; switching ON and OFF ventilation fans; and texting emergency messages. A trigger action plan for monitored attributes above normal and threshold value limits is programmed in the surface GIS management server. It is designed to turn the auxiliary fans on remotely or automatically in orange condition and sending evacuation messages for underground miners in unsafe (red) condition. Multi-users operation and 3D visualisations are other successful achievements of the proposed system for the underground monitoring and communication.
• Analysis of Radio Wave Propagation in an Urban Environment and its Application to Initial Disaster Response Support

  Youhei Kawamura, Hyongdoo Jang, Markus Wagner, Hajime Nobuhara, Ashraf M. Dewan, Bert Veenendaal, Itaru Kitahara

  JOURNAL OF DISASTER RESEARCH 10 (4) 655 - 666 1881-2473 2015/08/01 [Refereed][Not invited]
   

  When disasters strike, it is important to quickly collect and analyze disaster-related information immediately after the event. We have suggested ZigBee and geographic information systems (GIS) technologies to resolve these problems and provide an effective communications system. In this paper, a method for the rapid setup of short-range wireless networks infrastructure, which estimates the radio wave propagation and optimizes the positions of transmitters is proposed. Our estimation method is experimentally verified, and it combines ray-tracing with preliminarily obtained statistical attenuation information, which allows us to consider different types of the land and its elevation. Thus, we can determine the effective ranges for radio communication for each potential location in the actual environment. This information is then used in our optimization procedure to reduce the number of transmitters needed to establish connections.
• Investigation on the vibration generated by tourist activities Ⅱ―A case study of the Tomioka Silk Mill East Cocoon Warehouse―

  跡見,洋祐, 松井,敏也, 川村,洋平

  THe 32rd Annual Meeting of the Japan Society for Scientific Studies on Cultural Property Abstracts 日本文化財科学会 96 - 97 2015/07 [Not refereed][Not invited]
  
• Removal of arsenious acid from sulfuric acidic solution using ultrasound oxidation and goethite

  Hirokazu Okawa, Tomohiro Yoshikawa, Ryota Hosokawa, Shinji Hangui, Youhei Kawamura, Katsuyasu Sugawara

  JAPANESE JOURNAL OF APPLIED PHYSICS 54 (7) 0021-4922 2015/07/01 [Refereed][Not invited]
   

  We investigated the properties of synthetic goethite for the adsorption of As from strongly acidic solutions in ambient atmosphere under ultrasound irradiation. The goethite was successfully synthesized from iron-containing sulfuric acidic solution (1271 ppm) using an autoclave apparatus for 1h at 0.12MPa and 121 °C. The ratio of the iron eluted from the synthetic goethite to the acidic solution was only 0.58% at pH 2.1. Ultrasound irradiation (200 kHz, 200 W) was applied to oxidize 10 ppm of As(III) to As(V) at pH 2.2 for 60 min under various atmospheric conditions. Remarkably, the oxidation ratio of As(III) to As(V) is quite high (89.7%) at pH 2.2 in ambient atmosphere and is close to those obtained for Ar (95.3%) and O2 (95.9%) atmospheres. The As(III) removal ratio reached 94.5% after 60 min of irradiation. Therefore, goethite is a promising material for As adsorption using ultrasound oxidation in the acidic region in ambient atmosphere.
• Decision support system of unplanned dilution and ore-loss in underground stoping operations using a neuro-fuzzy system

  Hyongdoo Jang, Erkan Topal, Youhei Kawamura

  APPLIED SOFT COMPUTING 32 1 - 12 1568-4946 2015/07/01 [Refereed][Not invited]
   

  Abstract Unplanned dilution and ore-loss are the most critical challenges in underground stoping operations. These problems are the main cause behind a mine closure and directly influencing the productivity of the underground stope mining and the profitability of the entire operation. Despite being aware of the significance of unplanned dilution and ore-loss, prediction of these phenomena is still unexplained as they occur through complex mechanisms and causative factors. Current management practices primarily rely on similar stope reconciliation data and the intuition of expert mining engineers. In this study, an innovative unplanned dilution and ore-loss (uneven break: UB) management system is established using a neuro-fuzzy system. The aim of the proposed decision support system is to overcome the UB phenomenon in underground stope blasting which provides quantitative prediction of unplanned dilution and ore-loss with practical recommendations simultaneously. To achieve the method proposed, an uneven break (UB) prediction system was developed by an artificial neural network (ANN) considering 1076 datasets covering 10 major UB causative factors collected from three underground stoping mines in Western Australia. In succession, the UB consultation system was established via a fuzzy expert system (FES) in reference to surveyed results of fifteen underground-mining experts. The UB prediction and consultation system were combined as one concurrent neuro-fuzzy system that is named the 'uneven break optimiser'. Because the current UB prediction systems in investigated mines were highly unsatisfactory with correlation coefficient (R) of 0.088 and limited to only unplanned dilution, the performance of the proposed UB prediction system (R of 0.719) is a remarkable achievement. The uneven break optimiser can be directly employed to improve underground stoping production, and this tool will be beneficial not only for underground stope planning and design but also for production management.
• Unplanned dilution and ore loss prediction in longhole stoping mines via multiple regression and artificial neural network analyses

  H. Jang, E. Topal, Y. Kawamura

  JOURNAL OF THE SOUTHERN AFRICAN INSTITUTE OF MINING AND METALLURGY 115 (5) 449 - 456 2225-6253 2015/05 [Refereed][Not invited]
   

  Unplanned dilution and ore loss directly influence not only the productivity of underground stopes, but also the profitability of the entire mining process. Stope dilution is a result of complex interactions between a number of factors, and cannot be predicted prior to mining. In this study, unplanned dilution and ore loss prediction models were established using multiple linear and nonlinear regression analysis (MLRA and MNRA), as well as an artificial neural network (ANN) method based on 1067 datasets with ten causative factors from three underground longhole stoping mines in Western Australia. Models were established for individual mines, as well as a general model that includes all of the mine data-sets. The correlation coefficient (R) was used to evaluate the methods, and the values for MLRA, MNRA, and ANN compared with the general model were 0.419, 0.438, and 0.719, respectively. Considering that the current unplanned dilution and ore loss prediction for the mines investigated yielded an R of 0.088, the ANN model results are noteworthy. The proposed ANN model can be used directly as a practical tool to predict unplanned dilution and ore loss in mines, which will not only enhance productivity, but will also be beneficial for stope planning and design.
• Unplanned dilution and ore loss prediction in longhole stoping mines via multiple regression and artificial neural network analyses

  H. Jang, E. Topal, Y. Kawamura

  Journal of the Southern African Institute of Mining and Metallurgy 115 (5) 449 - 456 2225-6253 2015 [Refereed][Not invited]
   

  Unplanned dilution and ore loss directly influence not only the productivity of underground stopes, but also the profitability of the entire mining process. Stope dilution is a result of complex interactions between a number of factors, and cannot be predicted prior to mining. In this study, unplanned dilution and ore loss prediction models were established using multiple linear and nonlinear regression analysis (MLRA and MNRA), as well as an artificial neural network (ANN) method based on 1067 datasets with ten causative factors from three underground longhole stoping mines in Western Australia. Models were established for individual mines, as well as a general model that includes all of the mine data-sets. The correlation coefficient (R) was used to evaluate the methods, and the values for MLRA, MNRA, and ANN compared with the general model were 0.419, 0.438, and 0.719, respectively. Considering that the current unplanned dilution and ore loss prediction for the mines investigated yielded an R of 0.088, the ANN model results are noteworthy. The proposed ANN model can be used directly as a practical tool to predict unplanned dilution and ore loss in mines, which will not only enhance productivity, but will also be beneficial for stope planning and design.
• Development of technical measures for the preventive diagnosis of stone-built heritage site

  跡見,洋祐, 松井,敏也, 川村,洋平

  THe 31rd Annual Meeting of the Japan Society for Scientific Studies on Cultural Property Abstracts 日本文化財化学会 86 - 87 2014/07 [Not refereed][Not invited]
  
• An investigation of underground monitoring and communication system based on radio waves attenuation using ZigBee

  Mohammad Ali Moridi, Youhei Kawamura, Mostafa Sharifzadeh, Emmanuel Knox Chanda, Hyongdoo Jang

  TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 43 362 - 369 0886-7798 2014/07 [Refereed][Not invited]
   

  In the challenging environment and changing topology of a mine, reliable and effective communication is a high-stake issue along with the objectives of safe and efficient mining operations. Automation by remote and automatic systems have improved workplace health and safety for employees, cost-effectiveness, management of technical problems, energy saving, real-time response to events. In response to these challenges, wireless sensor networks (WSNs) have been widely employed in underground monitoring and communication systems for the purpose of environmental monitoring, positioning of workers and equipment, operational monitoring and communication system. Considering the capabilities of WSNs, ZigBee network is adapted. In this study, common WSNs are evaluated for application in underground mines and demonstrated why ZigBee network performance is suitable for such environments. ZigBee radio waves attenuation is investigated to evaluate stable communication range between ZigBee nodes at straight and curved tunnels in a real mine scenario. Moreover, experimental measurements of ZigBee radio waves attenuation are validated by simulation results. Based on the analysis of the experimental and simulation results, the effective factors on the radio waves attenuation in the junctions, curvatures and fields near and far from the source are assessed. Finally, stable wireless communication ranges between developed ZigBee nodes in the underground Angas Zinc Mine is concluded 100. m and 70. m for straight and curved tunnels, respectively. The development of ZigBee network application compared to other WSNs in underground mines is also approved. © 2014 Elsevier Ltd.
• Using GIS to develop a mobile communications network for disaster-damaged areas

  Youhei Kawamura, Ashraf M. Dewan, Bert Veenendaal, Masahiro Hayashi, Takeshi Shibuya, Itaru Kitahara, Hajime Nobuhara, Kento Ishii

  International Journal of Digital Earth 7 (4) 279 - 293 1753-8947 2014/04 [Refereed][Not invited]
   

  Communications network damage resulting from a large disaster causes difficulties in the ability to rapidly understand the current situation and thus make appropriate decisions towards mitigating problems, such as where to send and dispense emergency supplies. The research outlined in this paper focuses on the rapid construction of a network after a disaster occurs. This study suggests ZigBee and geographic information systems (GIS) technologies to resolve these problems and provide an effective communication system. The experimental results of the ZigBee network system are presented, examples are provided of the mapping and analysis undertaken using GIS for the disaster-stricken area of Tsukuba City, Japan, and the communications node arrangements are determined for this region. These results demonstrate the effectiveness of establishing such a communications system for supporting efforts to relieve disaster-damaged areas. © 2013 © 2013 Taylor & Francis.
• Estimation of underground sound source position from direct sounds and refected sounds from ground surface measured by a small number of geophone array

  川岸,卓司, 善甫,啓一, 水谷,孝一, 若槻,尚斗, 川村,洋平

  Journal of Japan Society of Civil Engineers, Ser.F3 (Civil Engineering Informatics) Japan Society of Civil Engineers 69 (2) I_130 - I_138 2185-6591 2014/03 [Refereed][Not invited]
   

  Recently, pipes like a water pipe or a gas tube are buried in wide area. Horizontal Directional Drilling (HDD) method is used as a pipe embedding method because the method requires no open cuts. However, the position of the drill-bit in underground is instability, and it must be estimated by extend sensors. We focused on the estimation method using the sound generated by the drill-bit itself. In this study, an estimation method of the drill-bit position using the reflected sound from ground surface as well as the direct sound from the drill-bit is proposed. Although the conventional method, which only uses the direct sound, requires a lot of geophones, the proposed method only requires an array consisting of some geophones. From some experiments in actual soil, it was verified that the proposed method was effective for estimating the position of the drill-bit. As the results, the proposed method enabled to estimate 3.42 times more accurately than the conventional method.
• Development of underground mine communication and monitoring systems by using ZigBee technology

  Y. Kawamura, M. A. Moridi, M. Sharifzadeh, H. Jang

  ISRM International Symposium - 8th Asian Rock Mechanics Symposium, ARMS 2014 1411 - 1420 2014 

  Data transfer and communication systems are first priority for further development of geotechnical monitoring. This paper describes a Wireless Sensor Network (WSN) for communication and monitoring systems based on ZigBee technology in underground mines. Wireless sensor networks (WSNs) have been widely employed in industries and the military with multiple applications to monitor environment, track target and telecommunicate data. Recently, WSNs have also been used for communication and monitoring systems in underground mines. In this study, a proposed WSN system of ZigBee network as one of the WSNs is investigated in underground mines regarding communication and monitoring systems to resolve operational challenges such as safety and gathering geotechnical information. Developed ZigBee wireless network system was installed in Paddington Gold Underground Mine (managed by Norton Gold Fields Limited). In this research, the intensity of received signal strength indication (RSSI) between wireless nodes within ZigBee network was investigated. Also, the optimal arrangement of ZigBee wireless nodes on the basis of radio wave attenuation and possibility of stable wireless communications which will be used for gathering some significant geotechnical information such as seismic, deformation and pressure were investigated. The experimental results indicate that a secure and stable ZigBee wireless network can be developed to overcome mentioned operational challenges in underground mining. It is obvious that this proposed system helps further progress in rock mechanics and geotechnical fields.
• Illustrating quality of life (QOL)

  Ashraf M. Dewan, Kamrun Nahar, Yohei Kawamura

  Dhaka Megacity: Geospatial Perspectives on Urbanisation, Environment and Health 239 - 256 2014/01/01 

  The objective of this chapter is to develop a quality of life (QOL) index at community level in the Dhaka City Corporation (DCC) area, which could describe the spatial patterns of QOL. Using remote sensing, census and other spatial data, a factor analysis was carried out to develop the different dimensions of QOL. Three principal factors were extracted from the analysis: environmental, economic and demographic. These three factors were then combined in a Geographic Information Systems (GIS) environment to construct a synthetic QOL for the study area. The results were subsequently validated using regression analysis, which revealed a better prediction of QOL based on environmental and socioeconomic variables. Interestingly, only a small portion of the population (1.4 %) in the study area was shown to have good QOL. As higher urban growth driven by rapid rural-urban migration is expected in Dhaka in the coming years, this study will be of substantial help for urban planners and policymakers in formulating related policies to ensure a better living environment for its inhabitants.
• A Magnetic Climbing Robot for Steel Bridge Inspection

  Rui Wang, Youhei Kawamura

  2014 11TH WORLD CONGRESS ON INTELLIGENT CONTROL AND AUTOMATION (WCICA) 2015-March (March) 3303 - 3308 2014 [Refereed][Not invited]
   

  Corrosion can cause section loss or cracks in the steel members which is one of the most important causes of deterioration of steel bridges. For some critical components of a steel bridge, it is fatal and could even cause the collapse of the whole bridge. Nowadays the most common approach to steel bridge inspection is visual inspection by inspectors with inspection trucks. This paper mainly presents a climbing robot with magnetic wheels which can move on the surface of steel bridge. Experiment results shows that the climbing robot can move on the steel bridge freely without disrupting traffic to reduce the risks to the inspectors.
• 2P6-2 Detection of Ship Screw Deflection Using Small Element Number of Hydrophone Array(Poster Session)

  Kawagishi,Takuji, Zempo,Keiichi, Mizutani,Koichi, Wakatsuki,Naoto, Ebihara,Tadashi, Kawamura,Youhei

  Proceedings of Symposium on Ultrasonic Electronics 超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会 34 357 - 358 1348-8236 2013/11 [Not refereed][Not invited]
  
• 地面反射を利用した土中の音源位置推定

  川岸,卓司, 善甫,啓一, 水谷,孝一, 若槻,尚斗, 川村,洋平

  土木学会, 2013年度土木情報学シンポジウム講演集 38 (12) 39 - 40 2013/09 [Not refereed][Not invited]
  
• A6 Application of sonication for separation and flotation of bitumen from oil sand

  Okawa Hirokazu, Saito Tomonao, Sugawara Katsuyasu, Kawamura Youhei, Babadagli Tayfun

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 22 11 - 12 2013 

  20% of Canada's oil sand is located on the surface of the ground. These oil sands are taken by means of open-pit mining. Oil sands contain about 10% bitumen. Bitumen is used as fuel energy, and it is necessary to separate bitumen from oil sand at high efficiency. Main industrial processes to separate bitumen from oil sand are treatments using hot water and steam in rotating drums. These treatments consist of two processes. The first is the bitumen separation from oil sand and the second is the bitumen flotation from aqueous solution to the solution surface. In this study, the role of high concentrated H_2O_2 to recover bitumen during sonication was investigated. Furthermore, we investigated the optimal combination of ultrasound and gases to improve the separation efficiency and the yield of bitumen from oil sand in the hot water process.
• Front edge location estimation for flexion axis using length meter with accelerometer and gyroscope

  Satoki Ogiso, Koichi Mizutani, Naoto Wakatsuki, Youhei Kawamura

  2013 IEEE 2nd Global Conference on Consumer Electronics, GCCE 2013 74 - 77 2013 [Refereed][Not invited]
   

  Front edge location estimation for flexion axis has been demanded in several fields such as civil engineering or construction. Recently, there are several methods to achieve front edge location estimation using gyroscope. However, these methods require such as fiber optic gyroscope to reduce the effect of the drift. Therefore, front edge location estimation using low-cost type of sensors is still demanded. In this paper, the front edge location estimation method for flexion axis using a triaxial gyroscope, accelerometer and a length meter was proposed, to achieve drift-free location estimation by low cost sensors. The performance of the proposed method was evaluated using reduced model. From the experiments, the major cause of the error (the drift of the gyroscope) was found to be reduced to 2/3 to 1/2 compared to the previous method, and the estimation error could be minimized within 4%. © 2013 IEEE.
• Investigation of Thermal Conductivity and Heat Characteristics of Oil Sands Using Ultrasound Irradiation for Shortening the Preheating Time

  Shingo Kamagata, Youhei Kawamura, Hirokazu Okawa, Koichi Mizutani

  JAPANESE JOURNAL OF APPLIED PHYSICS 51 (7) 07GE03  0021-4922 2012/07 [Refereed][Not invited]
   

  Oil sands are attractive as an energy resource. Bitumen, which is found in oil sands, has high viscosity, so that it does not flow. Most oil sands are underground and are developed with a method called steam-assisted gravity drainage (SAGD). Hot steam is injected underground to fluidize bitumen and promote its recovery. However, the preheating time is too long. One way of reducing running costs is by shortening the preheating time. Previous studies have found that bitumen can be extracted from oil sands efficiently by applying ultrasonic irradiation, but SAGD was not applied directly in these cases. Thus, the purpose of this study is to apply ultrasonic irradiation to SAGD, thereby shortening the preheating time of oil sands. As a model experiment for SAGD, heat transfer experiments in a sand layer made with Toyoura sand and silicone oil were conducted and the thermal effect with ultrasound was investigated. © 2012 The Japan Society of Applied Physics.
• Influence of Air Humidity and Water Particles on Dust Control Using Ultrasonic Atomization

  Hirokazu Okawa, Kentaro Nishi, Dai Shindo, Youhei Kawamura

  JAPANESE JOURNAL OF APPLIED PHYSICS 51 (7) 07GE06  0021-4922 2012/07 [Refereed][Not invited]
   

  The influence of air humidity and water particles on dust control was examined using ultrasonic atomization at 2.4 MHz, an acrylic box (61 L), and four types of ore dust samples: green tuff (4 μm), green tuff (6 μm), kaolin, and silica. It was clearly demonstrated that ultrasonic atomization was effective in raising humidity rapidly. However, at high relative air humidity, the water particles remained stable in the box without changing to water vapor. Ultrasonic atomization was applied to suppress dust dispersion and 40-95% dust reduction was achieved at 83% relative air humidity. Dust dispersion was more effective with ultrasonic atomization than without. © 2012 The Japan Society of Applied Physics.
• Emergency management withZigBeeand GIS

  Youhei Kawamura, Bert Veenendaal, Ashraf M. Dewan, Masahiro Hayashi, Itaru Kitahara, Hajime Nobuhara, Kento Ishii

  ISCIIA 2012 - 5th International Symposium on Computational Intelligence and Industrial Applications 2012 

  Communications network damage resulting from a large disaster causes difficulties in the ability to rapidly understand the current situation and thus make appropriate decisions toward mitigating problems. This research focuses on the rapid construction of a network after a disaster occurs. This study suggests ZigBee and GIS technologies to resolve these problems and provide an effective communications system. This paper provides ground design of the emergency management system with ZigBee network and GIS technologies. In this paper, it was demonstrated the effectiveness of establishing such a communications system for supporting efforts to relieve disaster-damaged areas.
• Development of digbot for monitoring the underground environment

  Masahiro Hayashi, Toshiyuki Miyachi, Youhei Kawamura, Kazutoshi Murakami, Yuichi Kato, Hiroshi Mochiyama

  ISCIIA 2012 - 5th International Symposium on Computational Intelligence and Industrial Applications 2012 

  A digging robot named "DigBot" has been developed by our laboratory for monitoring the underground environment and exploring the lunar surface. The purpose of this research is to develop the robot which can dig soil and sand automatically. When we build the building or structure, ground research is indispensable to know that if the ground can hold the building. In addition, conceivable application of DigBot is investigation of geological condition and ground pollution after disaster. Standard penetration test and Swedish weight sounding test are known as the general way of ground research and are frequently used. But these methods have faults. For example, high costs or large scale. In this proceeding, first, concept of DigBot is shown. As a basic research of developing DigBot, Contra-rotating drill is developed and made for trial purpose. And then digging experiment is carried out for verifying effectiveness through the Contra-rotating drill. It was proved that DigBot possess incomparably more power than ever before. This research suggest the way of solving faults by using the robot which can dig underground and research underground information.
• Efficient construction ofwireless personal area networks for disaster control

  Seiji Yasunobu, Hajime Nobuhara, Yohei Kawamura

  ISCIIA 2012 - 5th International Symposium on Computational Intelligence and Industrial Applications 2012 

  Japan and Indonesia are the earthquake occurrence countries where located in the circum-Pacific volcanic zone. Researches on disaster recovery management have been important issues for both countries. Our research proposes a Disaster Recovery Management system based on the proposed low cost short-distance wireless (ZigBee) communication network and mobile phones. If every person in the disaster area is connected to this network, then the information of the position, injured person, died person, and lost person can be identified quickly. The information is processed using our soft computing method to generate a comprehensive recovery and mitigation plan. Then, the government and the rescue team can use this recovery and mitigation plan for disaster management. Also, civilian organizations can develop own rescue projects based on the proposed networks. This can shorten time in the disaster management process therefore the number of victims can be reduced.
• 2Pa4-13 Influence of Air Humidity on Dust Control Using Ultrasound Atomization(Poster Session)

  Okawa,Hirokazu, Nishi,Kentaro, Shindo,Dai, Kawamura,Youhei

  Proceedings of Symposium on Ultrasonic Electronics 超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会 0 (32) 133 - 134 1348-8236 2011/11 [Not refereed][Not invited]
  
• A Method for Estimating the Location of the Drill-Bit During Horizontal Directional Drilling Using a Giant-Magnetostrictive Vibrator

  Junpei Tamura, Youhei Kawamura, Hidemi Mochiji, Naoto Sasaki, Koichi Mizutani, Hirokazu Okawa

  Japanese Journal of Applied Physics 50 07HC15-1 - 07HC12-6 1347-4065 2011/07 [Refereed][Not invited]
  
• A Method for Estimating the Location of the Drill-Bit During Horizontal Directional Drilling Using a Giant-Magnetostrictive Vibrator

  Junpei Tamura, Youhei Kawamura, Hidemi Mochiji, Naoto Sasaki, Koichi Mizutani, Hirokazu Okawa

  JAPANESE JOURNAL OF APPLIED PHYSICS 50 (7) 0021-4922 2011/07 [Refereed][Not invited]
   

  Horizontal directional drilling (HDD) is a commonly used method for laying pipelines that avoids the need to make an open cut. However, the location of the drill-bit underground must be known at all times when using this method. As conventional electromagnetic wave-based methods are known to have several problems, for example buildings in the line of construction, the moisture content of the ground and the presence of steel towers near the construction site. Herein we suggest a new method based on the propagation of elastic waves in the ground. Thus, measurement of the elastic waves generated by a giant-magnetostrictive vibrator by sensors set on the ground allows us to obtain the differences in arrival time of this wave at each sensor by applying a cross-correlation analysis to the waveforms detected. Finally, an approximate three-dimensional (3D) location method based on these differences was designed. © 2011 The Japan Society of Applied Physics.
• Recovery of Bitumen from Oil Sand by Sonication in Aqueous Hydrogen Peroxide

  Hirokazu Okawa, Tomonao Saito, Ryota Hosokawa, Takashi Nakamura, Youhei Kawamura, Shinobu Koda

  JAPANESE JOURNAL OF APPLIED PHYSICS 50 (7) 0021-4922 2011/07 [Refereed][Not invited]
   

  The surface of bitumen is hydrophobic; therefore, floatation separation using gas flow into the solution was considered an effective recovery mechanism of bitumen from oil sand. Low (28 kHz) and high (200 kHz) frequency sonication combined with floatation separation at 85°C were investigated to assess the effects of different ultrasound frequencies on the recovery rate and purity of bitumen from oil sand. Hydrogen peroxide was also used as a frothing agent. The role of highly concentrated H O (>100ppm) to recover bitumen during sonication was investigated. Hydrogen peroxide formed a bubble around the bitumen, which made it rise more easily to the solution surface during sonication. The result showed a good recovery rate of bitumen. 28 kHz sonication combined with H O was a more appropriate method than that of 200 kHz to recover bitumen in a short time because of its strong stripping action caused by a strong jet flow. © 2011 The Japan Society of Applied Physics. 2 2 2 2
• Sonication enables effective iron leaching from green tuff at low temperature

  Takashi Nakamura, Hirokazu Okawa, Youhei Kawamura, Katsuyasu Sugawara

  Japanese Journal of Applied Physics 50 (7 PART 2) 0021-4922 2011/07 [Refereed][Not invited]
   

  Ultrasound irradiation (28 and 200 kHz) was applied to iron leaching from green tuff into a low temperature solution (20°C) using oxalic acid. Ultrasound irradiation increased the amount of iron leached from the green tuff and was greater than that leached by stirring. It is thought that the jet flow caused by the collapse of cavities during ultrasound irradiation prevents and strips the deposits of iron oxalate from the green tuff particles. The extraction of iron at 28 kHz displayed better performance than that at 200 kHz for three reasons. The first is that the jet flow generated by cavitation bubble collapse at 28 kHz is thought to be stronger than that at 200 kHz. The second is that the crushing action of ultrasound irradiation at 28 kHz is greater than that at 200 kHz. The third is that 200 kHz irradiation generates OH radicals, which prevents the generation of FeH(C O ) and oxidizes FeH(C O ) to Fe(C O ), creating a cover layer on the surface of the stone. Thus, to leach iron from the ore, it is effective to use ultrasound irradiation at 28 kHz, which prevents the creation of radicals and breaks down the grain size. © 2011 The Japan Society of Applied Physics. 2 4 2 4 2 4 + +
• Sonication Enables Effective Iron Leaching from Green Tuff at Low Temperature

  Takashi Nakamura, Hirokazu Okawa, Youhei Kawamura, Katsuyasu Sugawara

  JAPANESE JOURNAL OF APPLIED PHYSICS 50 (7) 07HE16 - 07HE16-4 0021-4922 2011/07 [Refereed][Not invited]
   

  Ultrasound irradiation (28 and 200 kHz) was applied to iron leaching from green tuff into a low temperature solution (20 degrees C) using oxalic acid. Ultrasound irradiation increased the amount of iron leached from the green tuff and was greater than that leached by stirring. It is thought that the jet flow caused by the collapse of cavities during ultrasound irradiation prevents and strips the deposits of iron oxalate from the green tuff particles. The extraction of iron at 28 kHz displayed better performance than that at 200 kHz for three reasons. The first is that the jet flow generated by cavitation bubble collapse at 28 kHz is thought to be stronger than that at 200 kHz. The second is that the crushing action of ultrasound irradiation at 28 kHz is greater than that at 200 kHz. The third is that 200 kHz irradiation generates OH radicals, which prevents the generation of FeH(C(2)O(4))(+) and oxidizes FeH(C(2)O(4))(+) to Fe(C(2)O(4)), creating a cover layer on the surface of the stone. Thus, to leach iron from the ore, it is effective to use ultrasound irradiation at 28 kHz, which prevents the creation of radicals and breaks down the grain size. (C) 2011 The Japan Society of Applied Physics
• Ultrashallow Underground Imaging System For Detecting Buried Object Using Giant-Magnetostriciton Vibrator

  KAMOHARA,Akihiro, KAWAMURA,Youhei, KAMAGATA,Shingo, OKAWA,Hirokazu

  Journal of MMIJ 社団法人 資源・素材学会 127 (4) 182 - 188 1881-6118 2011/03 [Refereed][Not invited]
   

  Recently, Water and gas pipes are developed frequently because of the increased urban population. When the underground piping is constructed, drawings and signs are needed to drill the ground. However, underground pipings and other buried objects are often buried in different locationscompared with drawings. Underground pipings, the rock and the gravel interfere with construction. It is necessary to avoid this situation. To determine the construction of underground pipes, the non-destructive imaging method previously detects the pipe inside the ground. This paper describes a system of ultrashallow underground imaging method using seismic reflection and seismic giant magnetostrictive transducer. We apply a surface wave analysis using a giant magnetostrictive transducer. We improve the accuracy of P wave velocity. For the high-efficiency setup and the underground imaging succeed. This system combines ultrashallow seismic reflection and the ultra-magnetostrictive transducer. It provides the practical system.
• Development of high pressure viscosity meter using hall element

  Ando Hiroshi, Sasaki Kyuro, Kawamura Youhei, Okawa Hirokazu, Sugai Yuichi

  Proceeding of Annual/Fall Meetings of the Japan Petroleum Institute 公益社団法人 石油学会 2011 103 - 103 2011 

  高圧条件下において粘度を計測する手法は、大掛かりで非常にコストを要するものであった。本研究において、このような高圧条件下においても、簡便に粘度を計測できる手法を開発した。磁石の磁場をホール素子で計測することにより、流体中における磁石の落下運動を非接触で計測し、落体法を用いて流体の粘度を決定した。この計測手法を用いることで、圧力容器など高圧条件である容器内においても、機密性を保った流体の粘度計測をすることができる。
• Solid-liquid separation by sonochemistry: A new approach for the separation of mineral suspensions

  Takashi Nakamura, Hirokazu Okawa, Youhei Kawamura, Katsuyasu Sugawara

  ULTRASONICS SONOCHEMISTRY 18 (1) 85 - 91 1350-4177 2011/01 [Refereed][Not invited]
   

  The effect of sonochemistry to acidify solutions was applied for the solid-liquid separation of three kinds of mineral suspensions. At first, the relationship was measured between zeta-potential and pH in these suspensions to find pH levels correspondent to the isoelectric points. Then sonication (200 kHz or 28 kHz) was applied to adjust pH to the isoelectric points and separated particles from solutions by still-standing and spontaneous precipitation. Compared to the conventional methods using filters and chemical agents, the advantage of this sonochemical separation is two-fold. First, it does not require the maintenance of filters. Second, separated particles are easy to use since they are not mixed with pH adjusters and chemical flocculants. Isoelectric zone (ion strength 0.01, concentration 0.001 wt.%) of green tuff, andesite and titanium dioxide suspensions tested in this study were pH 1.1-3.7, 0.8-3.4, 2.7-5.7, respectively. The sonication of green tuff and andesite suspensions at 200 kHz changed the pH to the isoelectric zone despite the pH buffering effect of eluted alkali earth metals, and successfully precipitated the particles. On the contrary, the sonication of these suspensions at 28 kHz failed to adjust pH to the isoelectric zone, and the particles did not precipitate. In addition, the degradation of particles was observed in the SEM photographs of particles sonicated at 28 kHz, whereas no significant change was detected in particles sonicated at 200 kHz. Thus, it is concluded that the optimal frequency is about 200 kHz because its strong chemical effect can easily adjust the pH while its relatively weak physical effect prevents the degradation of particles. © 2010 Elsevier B.V.
• 3Pb2-6 Basic Study on Location Estimation of Drill-bit Using Giant-magnetostrictive Vibrator on Simulated Ground(Poster Session)

  Tamura Junpei, Kawamura Youhei, Mochiji Hidemi, Sasaki Naoto, Okawa Hirokazu, Mizutani Koichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 32 (32) 477 - 478 1348-8236 2011 [Not refereed][Not invited]
  
• 3Pa4-1 A Fundamental Study of Applying Ultrasonic Waves in 20 kHz Band Frequency to the Method of Preheating the Oil Sand(Poster Session)

  Kamagata Shingo, Kawamura Youhei, Okawa Hirokazu, Mizutani Kouichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 32 (32) 371 - 372 1348-8236 2011 [Not refereed][Not invited]
  
• 2P-42 The use of ultrasound irradiation for extracting bitumen from oil sand at low temperature(Poster Session)

  Okawa,Hirokazu, Hosokawa,Ryota, Saito,Tomonao, Nakamura,Takashi, Kawamura,Youhei

  Proceedings of Symposium on Ultrasonic Electronics 超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会 0 (31) 373 - 374 1348-8236 2010/12 [Refereed][Not invited]
  
• 2P-35 Improvement in efficiency of iron leaching from green tuff using sonication and oxalic acid(Poster Session)

  Nakamura,Takashi, Okawa,Hirokazu, Kawamura,Youhei, Sugawara,Katsuyasu

  Proceedings of Symposium on Ultrasonic Electronics 超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会 0 (31) 359 - 360 1348-8236 2010/12 [Refereed][Not invited]
  
• The sterilization of suspensions contaminated with microorganisms using ultrasound irradiation

  T.Nakamura, H.Okawa, R.Hosokawa, T.Saito, Y.Kawamura, and, K.Sugawara, 川村, 洋平

  Jpn. J. of Appl. Phys. 応用物理学会 49 07HE11  2010/08 [Refereed][Not invited]
  
• The Sterilization of Suspensions Contaminated with Microorganisms Using Ultrasound Irradiation

  Takashi Nakamura, Hirokazu Okawa, Ryouta Hosokawa, Tomonao Saito, Youhei Kawamura, Katsuyasu Sugawara

  JAPANESE JOURNAL OF APPLIED PHYSICS 49 (7) 0 - 0 0021-4922 2010/07 [Refereed][Not invited]
   

  We investigated the influence of suspended particles on the sterilization efficiency of ultrasound wave applied to microbial suspensions. A microbial solution containing 2:0 × 10 cfu/ml of Bacillus bacteria but no suspended particles was sterilized more efficiently by 28 kHz irradiation inducing a strong impact-like physical action compared to 200 kHz irradiation inducing a strong chemical reaction through the generation of radicals and heat. This sterilization effect was enhanced by the suspension of silicon dioxide or green tuff when irradiated at 28 kHz. However, the irradiation of green tuff microbial suspension at 200 kHz resulted in a remarkable decrease in the sterilization efficiency. This reduction was caused by divalent iron in green tuff reacting with radicals generated by 200 kHz irradiation, thus reducing the amount of radicals used for sterilization. Our results suggest that 28 kHz ultrasound irradiation is optimal for the sterilization of microbial suspensions. © 2010 The Japan Society of Applied Physics. 2
• Effects of Different Ultrasound Irradiation Frequencies and Water Temperatures on Extraction Rate of Bitumen from Oil Sand

  Hirokazu Okawa, Tomonao Saito, Ryota Hosokawa, Takashi Nakamura, Youhei Kawamura, Katsuyasu Sugawara

  JAPANESE JOURNAL OF APPLIED PHYSICS 49 (7) 0 - 0 0021-4922 2010/07 [Refereed][Not invited]
   

  Low (28 kHz) and high (200 kHz) frequency sonication combined with hot water treatments at 45 and 75 °C were investigated to assess the effects of different ultrasound frequencies and water temperatures on the extraction of bitumen from oil sand. A mechanical stirrer was also used to compare the efficiency of separation. Bitumen extraction tests were performed under argon, air, and nitrogen atmospheres. Sonication at 200 kHz was shown to extract bitumen effectively from oil sand at 75 °C. The bitumen extraction rate for sonication at 200 kHz was slightly higher than that at 28 kHz. For low temperature (45 °C) solutions, only sonication at 28 kHz could extract bitumen from oil sand, demonstrating that sonication at 28 kHz can effectively breakdown the oil sand aggregates into a suspension. © 2010 The Japan Society of Applied Physics.
• The Sterilization of Suspensions Contaminated with Microorganisms Using Ultrasound Irradiation

  Nakamura,Takashi, Okawa,Hirokazu, Hosokawa,Ryouta, Saito,Tomonao, Kawamura,Youhei, Sugawara,Katsuyasu

  Jpn J Appl Phys Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics 49 (7) 07HE11 - 07HE11-4 0021-4922 2010/07 [Refereed][Not invited]
   

  We investigated the influence of suspended particles on the sterilization efficiency of ultrasound wave applied to microbial suspensions. A microbial solution containing $2.0\times 10^{2}$ cfu/ml of Bacillus bacteria but no suspended particles was sterilized more efficiently by 28 kHz irradiation inducing a strong impact-like physical action compared to 200 kHz irradiation inducing a strong chemical reaction through the generation of radicals and heat. This sterilization effect was enhanced by the suspension of silicon dioxide or green tuff when irradiated at 28 kHz. However, the irradiation of green tuff microbial suspension at 200 kHz resulted in a remarkable decrease in the sterilization efficiency. This reduction was caused by divalent iron in green tuff reacting with radicals generated by 200 kHz irradiation, thus reducing the amount of radicals used for sterilization. Our results suggest that 28 kHz ultrasound irradiation is optimal for the sterilization of microbial suspensions.
• Effects of different ultrasound irradiation frequencies and water temperatures on extraction rate of bitumen from oil sand

  Hirokazu Okawa, Tomonao Saito, Ryota Hosokawa, Takashi Nakamura, Youhei Kawamura, Katsuyasu Sugawara

  Japanese Journal of Applied Physics 49 (7) 07HE12  0021-4922 2010/07 [Refereed][Not invited]
   

  Low (28 kHz) and high (200 kHz) frequency sonication combined with hot water treatments at 45 and 75 °C were investigated to assess the effects of different ultrasound frequencies and water temperatures on the extraction of bitumen from oil sand. A mechanical stirrer was also used to compare the efficiency of separation. Bitumen extraction tests were performed under argon, air, and nitrogen atmospheres. Sonication at 200 kHz was shown to extract bitumen effectively from oil sand at 75 °C. The bitumen extraction rate for sonication at 200 kHz was slightly higher than that at 28 kHz. For low temperature (45 °C) solutions, only sonication at 28 kHz could extract bitumen from oil sand, demonstrating that sonication at 28 kHz can effectively breakdown the oil sand aggregates into a suspension. © 2010 The Japan Society of Applied Physics.
• 20712 Development of Mobile Mechanism Using Magnetic Wheels for Non-Destructive Testing Device of Iron Bridge

  HIJIKATA,Daisuke, KAWAMURA,Youhei, UTSUGI,Takahiro

  日本機械学会関東支部総会講演会講演論文集 一般社団法人日本機械学会 2010 (16) 231 - 232 2010/03 [Not refereed][Not invited]
   

  We develop a mobile mechanism that can move on the surface of the iron bridge for a non-destructive testing device. This mechanism has four-wheel drive and moves by means of magnetic wheels. It acquires adhesion force efficiently by using the principle of the magnetic circuit. This mechanism achieved vertical plane running. Next, we analyze mechanics when the machine approaches a step. It turns out that getting over steps and climbing a vertical plane become possible by selecting the appropriate parameter. It was confirmed by the experiment.
• P13 The ultrasonic irradiation for purifying suspension contaminated with trichloroethylene(Poster session)

  Okawa Hirokazu, Nakamura Takashi, Kawamura Youhei, Sugawara Katsuyasu

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 19 45 - 46 2010 

  In this paper, we demonstrate in a treatment method for suspension contaminated with trichloroethylene (TCE). The objectives of the present work are to study the purifying the suspension contaminated with TCE and the precipitating the fine particles in the suspension using ultrasound irradiation. Suspension and solution were prepared by ion-change water, TCE and green tuff. TCE solution (500ppm) was completely decomposed for 2h sonication in argon atmosphere. And TCE in suspension (500ppm) was also confirmed the completely decomposition at same condition. Compared the decomposition rate of TCE in solution and suspension, the value were almost same. Isoelectric zone of green tuff suspension was 1.4-3.8 in pH. Degradation of TCE generated which was able to be acidified the solution and the suspension to the pH level of the isoelectric zone. TCE purifying and solid-liquid separation of the suspension using ultrasound irradiation was feasible.
• 1Pa-12 3D Location Estimation of Drill-bit for HDD Method Using Giant-magnetostrictive Vibrator(Poster Session)

  KAWAMURA Youhei, TAMURA Junpei, Mochiji Hidemi, Mizutani Koichi, Okawa Hirokazu

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 31 (31) 39 - 40 1348-8236 2010 [Refereed][Not invited]
  
• Performance evaluation of Contra-Rotating drill for DIGBOT

  Ryouhei Abe, Youhei Kawamura, Kazushi Kamijima, Kazutosi Murakami

  Proceedings of the SICE Annual Conference 885 - 888 2010 [Refereed][Not invited]
   

  In this research, we suggest and develop a small digging robot. This robot is named DigBot. Conceivable application of DigBot is geotechnical investigation and moon exploration. Basic concept of DigBot is proposed and prototype is manufactured using new drilling method'Contra-Rotating drill'. © 2010 SICE.
• Development of the landslide observation system using ZigBee

  Yuya Nakahata, Youhei Kawamura

  Proceedings of the SICE Annual Conference 1191 - 1194 2010 [Refereed][Not invited]
   

  Landslides are concern in many parts of Japan, and these measures are currently not sufficient.It is necessary to observe the outbreak of the landslide, and the development of the automatic observation system of the landslide is demanded. Therefore, in this research, we suggest and develop an automatic observation system of the landslide using ZigBee. Then, it was confirmed that whether created system using ZigBee can use for observation landslides. © 2010 SICE.
• Viscosity Measurement Method using Induced EMF at Coil in PVT Apparatus

  H.ANDO, Y.KAWAMURA, H.OKAWA, Y.SUGAI, and, K.SASAKI, 川村, 洋平

  International Symposium on Earth Science and Technology 2009 443-446  2009/12 [Refereed][Not invited]
  
• A Fundamental Study of the Surface-Wave Method: The Use of a Giant-Magnetostriction Vibrator as Seismic Source

  A.KAMOHARA, Y.KAWAMURA, Y.NAKAHATA, H.OKAWA, and, K.MIZUTANI, 川村, 洋平

  International Symposium on Earth Science and Technology 2009 437-442  2009/12 [Refereed][Not invited]
  
• 2P4-17 The application of sonication for purifying soil contaminated with microorganism(Poster Session)

  Nakamura,Takashi, Okawa,Hirokazu, Kawamura,Youhei, Sugawara,Katsuyasu

  Symposium on ultrasonic electronics 超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会 0 (30) 317 - 318 2009/11 [Refereed][Not invited]
  
• 1P4-33 Research on the extraction of bitumen from oil sand treated by ultrasound irradiation(Poster Session)

  Okawa,Hirokazu, Hosokawa,Ryota, Saito,Tomonao, Nakamura,Takashi, Kawamura,Youhei

  Symposium on ultrasonic electronics 超音波エレクトロニクスの基礎と応用に関するシンポジウム運営委員会 0 (30) 151 - 152 2009/11 [Refereed][Not invited]
  
• Research on the New Method to Precipitate Hinai Green Tuff Suspension using Ultrasound Irradiation

  NAKAMURA,Takashi, OKAWA,Hirokazu, KAWAMURA,Youhei, TAKAHATA,Shigeyuki, NAKA,Hideo, SUGAWARA,Katsuyasu

  Resources Processing 環境資源工学会 56 (1) 13 - 20 1348-6012 2009/04 [Refereed][Not invited]
   

  Hinai green tuff is quarried in Odate-shi, Akita prefecture in Japan and used for architectural materials. Hinai green tuff suspension is generated from the cutting and the grinding process and it is necessary to treat the solution with precipitants. A chemical flocculant has been used as a precipitation agent for fine particles in the suspension. However, using a chemical flocculant agent produces a wasteful mixture of particles and flocculants, which are impossible to be used as a resource. Therefore, it is necessary to develop a new precipitation method without using precipitants for green tuff particles. In this study, the zeta potential of Hinai green tuff particles in suspension was measured to gain the basic electrochemical properties of the colloidal suspension. We then developed a new precipitation method using sonochemical reaction at 200 kHz, 200 W. From results of the zeta potential measurement using an electrophoresis method, the particles exhibited −50 mV at pH 7.0 and 0 mV at below pH 4.0. Sonochemical reaction was applied to control the pH of the suspension to precipitate the Hinai green tuff particulate. When ultrasonic irradiation was applied to the Hinai green
• P21 Ultrasonic irradiation for purifying suspension contaminated with chlorinated organic compound

  Nakamura Takashi, Okawa Hirokazu, Kawamura Youhei, Sugawara Katsuyasu

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 18 69 - 70 2009 

  We present a method to treat suspension contaminated with trichloroethylene (TCE). We aimed to remove TCE and precipitate the fine particles in the suspension using ultrasound irradiation. The solution was prepared from ion-change water and TCE. The suspension was prepared from the solution and green tuff. TCE solution (500ppm) was completely decomposed by 2h sonication in argon atmosphere. And the complete decomposition of TCE in suspension (500ppm) was also confirmed at the same condition. The decomposition rate of TCE in solution and suspension were almost same. Isoelectric zone of green tuff suspension was 1.4-3.8 in pH. The degradation of TCE acidified the solution and brought the pH level of the suspension to the isoelectric zone. Thus, it is feasible to remove TCE and precipitate fine particles in the suspension using ultrasound irradiation.
• 1P2-34 Validation of Applicability of Surface-wave Method Using Giant-magnetostriction Vibrator as Seismic Source(Poster Session)

  Kamohara Akihiro, Kawamura Youhei, Nakahata Yuya, Okawa Hirokazu, Mizutani Koichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 30 (30) 83 - 84 1348-8236 2009 [Refereed][Not invited]
  
• A Method of Underground Imaging Using Value of Elliptic Orbit Brightness for Detecting Underground Piping

  KAWAMURA Youhei, KO Takanari, KAMOHARA Akihiro, OKAWA Hirokazu

  Journal of MMIJ 資源・素材学会 124 (12) 801 - 807 1881-6118 2008/12/25 [Refereed][Not invited]
   

  When underground piping for a water or gas supply is buried, the construction site should be checked in advance, referring to the plan or sign. However, some obstacles, such as unknown pipes or stones, can be encountered. To avoid these cases, an examination of the underground condition is required. The purpose of this study is to detect underground objects that exist in the ultra-shallow layer, where 2-3 m below the surface, and to obtain underground image which is easy to see intuitively. For detection, seismic method is applied. However, this method has two downsides. One is a generally used seismic source not having reproducibility. The other is mixing Rayleigh wave which is one of the surface waves and reflected waves. To compensate these downsides, giant-magnetostriction vibrator was used as a seismic source, and magnified cross-correlation analysis was proposed. Underground image was obtained using combinations of them. In this paper, as the method of underground imaging, new algorithm of elliptic orbit brightness value it was developed by the authors was used.
• Accuracy Improvement of Cepstrum Analysis Using Giant-magnetostriction Vibrator Applied to Non-destructive Testing for Crack of Rock Slope

  M.Asaka, Y.Kawamura, H.Okawa, K.Mizutani, 川村, 洋平

  Proceedings of the 17th Int. Symposium on Mine Planning and Equipment Selection 744-754  2008/10 [Refereed][Not invited]
  
• Applicability in Cepstrum Analysis Using Giant-Magnetostriction Vibrator Applied to Non-destructive Testing of Concrete Construction and Rock Slope

  KAWAMURA Youhei, ASAKA Michinori, KO Takanari, OKAWA Hirokazu, MIZUTANI Koichi

  Journal of MMIJ 一般社団法人 資源・素材学会 124 (6) 452 - 458 1881-6118 2008/07/25 [Refereed][Not invited]
   

  Buildings are often damaged by earthquake and land sinkage. Moreover, in Japan, concrete constructions built during the period of high economic growth are getting old. On the other hand, due to weather and geographical features, the collapse of rock slope occurs in many places. So, authors have been conducting a study of the safety assessment of concrete constructions and rock slope using reflection wave method. In this study, the giant-magnetostriction vibrator was used as a transducer to input the ultrasonic wave into a concrete block. Giant-magnetostriction vibrators have much greater input power than piezo-electric ceramics. So, the safety assessment of large scale objects that do not respond with piezo-electric ceramics is possible. These researches are generally called "Non-destructive testing" and herculean task due to the influence of direct wave, because the output wave contains a wave with direct wave and reflection wave together. In this study, as the method to detect the reflection wave, cepstrum analysis was adopted, and arrival times of reflection waves from the bottom of concrete block are shown. The result of cepstrum analysis is greatly influenced by the noise. To improve the result of analysis, the window function which is used in the process of cepustrum analysis was focused, and reduced the influence of direct wave using input voltage waveform. Moreover, the addition of the results of cepstrum analyses in different frequency was applied and the result was greatly improved. The result of this research shows that the cepstrum analysis with giant-magnetostriction vibrator for non-destructive testing is available.
• Underground Imaging Method Using Magnified Cross-Correlation Analysis

  Euiseong Ha, Youhei Kawamura, Koichi Mizutani, Akihiro Kamohara, Hirokazu Okawa

  JAPANESE JOURNAL OF APPLIED PHYSICS 47 (5) 3946 - 3951 0021-4922 2008/05/23 [Refereed][Not invited]
   

  When underground piping for a water supply or gas supply is buried, some obstacles such as unknown pipes or stones can be encountered. To avoid such situations, an examination of the underground condition from the ground surface is needed. For such an examination, the ultrashallow reflection method is used. We use a giant-magnetostriction vibrator as a seismic source and a magnified cross-correlation analysis as an analysis method. This analysis is performed to obtain the arrival time of waves reflected from underground objects. In this study, an underground imaging method is proposed using the magnified cross-correlation analysis and a simulation is conducted. Then the experiment of detecting a buried concrete block is conducted. Finally, the imaging method is applied to the experimental result, and then the underground image is obtained. With this imaging method, the position of the buried concrete block can be estimated. © 2008 The Japan Society of Applied Physics.
• Synthesis of FePO4 cathode material for lithium ion batteries by a sonochemical method

  Hirokazu Okawa, Junpei Yabuki, Youhei Kawamura, Ichiro Arise, Mineo Sato

  MATERIALS RESEARCH BULLETIN 43 (5) 1203 - 1208 0025-5408 2008/05/06 [Refereed][Not invited]
   

  Hydrated amorphous FePO was synthesized by a sonochemical reaction method, in which a solution of (NH ) HPO and FeSO ·7H O was irradiated by an ultrasonic wave. From this material, two kinds of cathode materials were easily prepared: (1) an amorphous sample prepared by heating at 350 °C and (2) a crystalline sample prepared by heating at 700 °C. Both samples consisted of homogeneous sub-micron particles. The amorphous sample of FePO exhibited high discharge capacities with more than 100 mAh g in the range of 3.9-2.0 V versus Li/Li at a current rate of 0.2 C. The sonochemical synthesis proposed herein has the following advantages: no use of oxidation agents for production of trivalent iron ions, reduction in reaction time, control of particle size, and enlargement in surface area for the preparation of the cathode material. © 2007 Elsevier Ltd. All rights reserved. 4 4 2 4 4 2 4 -1 +
• Underground Imaging Method Using Magnified Cross-Correlation Analysis

  Ha, Euiseong, Kawamura, Youhei, Mizutani, Koichi, Kamohara, Akihiro, Okawa, Hirokazu

  JAPANESE JOURNAL OF APPLIED PHYSICS JAPAN SOCIETY APPLIED PHYSICS 47 (5:Part 2) 3946 - 3951 0021-4922 2008/05 [Refereed][Not invited]
  
• A13 Research on a new precipitation method of Hinai green tuff suspension by ultrasound irradiation(Oral session)

  Nakamura Takashi, Okawa Hirokazu, Kawamura Yohei, Sugawara Katsuyasu

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 17 36 - 37 2008 

  Hinai green tuff is quarried in Odate-shi, Akita prefecture in Japan and used for architectural materials. Hinai green tuff suspension is generated from the grinding process and it is necessary to treat the solution with precipitants. A chemical flocculant has been used as a precipitation agent for fine particles in the suspension. However, using a chemical flocculant agent produces a wasteful mixture of particles and flocculants, which are impossible to be used as a resource. Therefore, it is necessary to develop a new precipitation method without using precipitants for green tuff particles. In this study, the zeta potential of Hinai green tuff particles in suspension was measured to gain the basic electrochemical properties of the suspension. We then developed a new precipitation method using sonochemical reaction at 200kHz, 200W. From results of the zeta potential measurement using an electrophoresis method, the particles exhibited 0mV at below pH 4.5. Sonochemical reaction was applied to control the pH of the suspension to precipitate the Hinai green tuff particulate. When ultrasonic irradiation was applied to the Hinai green tuff suspension, the pH decreased to 4.5 in 70 min and finally reached 3.4 in 180 min. We successfully extracted pure Hinai green tuff particles as precipitates from the suspension using ultrasound irradiation.
• P07 Synthesis of LiFePO_4 Cathode Material for Lithium Ion Battery Treated by Sonochemical Method(Part I,Poster session)

  Kudo Yota, Okawa Hirokazu, Kawamura Youhei, Sugawara Katsuyasu, Sato Mineo

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 17 54 - 55 2008 

  Lithium iron phosphate has attracted attention as a promising cathode material for lithium ion battery, because of its less expensive, abundance. However, the battery capability of this material is at present limited by its low electronic conductivity and low lithium diffusion rate. In order to improve the poor diffusion of lithium ions and the low electronic conductivity, mainly two possible approaches have been studied. One is to increase the surface area of active materials which can reduce the ion-diffusion pathway, and the other is to deposit conductive carbon layers on the surface to improve electronic conductivity. Since the surface area is dependent on the particle size of LiFePO_4, the synthetic method is very important to control the particle size. In this study, Olivine-type LiFePO_4 was prepared via a sonochemical reaction to gain the fine particles. LiOH・H_2O, (NH_4)_2HPO_4 and FeSO_4・7H_2O were used as the starting materials. An Alcohol was added to the solution of the raw materials. When ultrasonic irradiation upon an alcohol, it is so effective for prohibition of conversion from Fe^<2+> to Fe^<3+> in the solution without reducing agent. The precipitate prepared from the solution gave fine particles of LiFePO_4 after calcination. The LiFePO_4 powders obtained was of homogeneity and globular structure with sub-micron particle sizes.
• 筑波大学 川村研究室 : Geo-Sensing

  川村, 洋平

  計測と制御 = Journal of the Society of Instrument and Control Engineers 46 (10) 815 - 816 0453-4662 2007/10/10 [Refereed][Not invited]
  
• Study on Correspondence between Output Voltage of Cable Sensor for Vibration Detection and Velocity

  Y.Kudo, Y.Kawamura, K.Oumura, H.Okawa, and, K.Mizutani, 川村, 洋平

  Proceedings of the 16th Int. Symposium on Mine Planning and Equipment Selection 524-531  2007/09 [Refereed][Not invited]
  
• Detection of underground concrete block using giant-magnetostriction vibrator applying magnified cross-correlation analysis

  Eui Seong Ha, Youhei Kawamura, Koichi Mizutani, Hirokazu Okawa, Michinori Asaka

  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 46 (7B) 4500 - 4503 0021-4922 2007/07/26 [Refereed][Not invited]
   

  When underground piping for a water supply or gas supply is buried, some obstacles such as unknown pipes or stones can be encountered. To avoid such situations, an examination of the underground condition from the ground surface is needed. For such an examination, the ultra-shallow reflection method is used. We use a giant-magnetostriction vibrator as the seismic source. In this study, first, the P-wave directivity of the giant-magnetostriction vibrator is clarified. Second, the experiment of detecting a buried concrete block is conducted. In this experiment, the cross-correlation analysis is applied. However, the arrival time of the wave reflected from the concrete block is not confirmed. On the basis of the P-wave directivity of the giantmagnetostriction vibrator, the causes are assumed. To obtain good results, the magnified cross-correlation analysis is proposed. By this analysis, the depth at which the concrete block is buried can be estimated with high accuracy. © 2007 The Japan Society of Applied Physics.
• Detection of underground concrete block using giant-magnetostriction vibrator applying magnified cross-correlation analysis

  Eui Seong Ha, Youhei Kawamura, Koichi Mizutani, Hirokazu Okawa, Michinori Asaka

  Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 46 (7 B) 4500 - 4503 0021-4922 2007/07/26 [Refereed][Not invited]
   

  When underground piping for a water supply or gas supply is buried, some obstacles such as unknown pipes or stones can be encountered. To avoid such situations, an examination of the underground condition from the ground surface is needed. For such an examination, the ultra-shallow reflection method is used. We use a giant-magnetostriction vibrator as the seismic source. In this study, first, the P-wave directivity of the giant-magnetostriction vibrator is clarified. Second, the experiment of detecting a buried concrete block is conducted. In this experiment, the cross-correlation analysis is applied. However, the arrival time of the wave reflected from the concrete block is not confirmed. On the basis of the P-wave directivity of the giantmagnetostriction vibrator, the causes are assumed. To obtain good results, the magnified cross-correlation analysis is proposed. By this analysis, the depth at which the concrete block is buried can be estimated with high accuracy. © 2007 The Japan Society of Applied Physics.
• The detection of a misfiring cylinder of diesel engines in excavation machinery using ALM analysis

  Y. Kawamura, M. Nagayama, M. Ujihira

  International Journal of Mining, Reclamation and Environment 21 (2) 97 - 110 1748-0930 2007/06 [Refereed][Not invited]
   

  Mechanical problems, common in large mining equipment, result in serious losses in operations efficiency and financial return. In this study, a minimum number of sensors was applied on the side of two cylinders of a diesel engine in order to build an abnormality diagnostic system that detects anomalous engine behaviour at an early stage. The study investigates whether or not the misfiring of an engine cylinder can be detected through analysis of acceleration results using an aggregative learning method (ALM). The results show that, using ALM, distinctive differences could be observed in almost every cylinder except those farthest from the accelerometer.
• 土石流の巨礫の挙動に関する個別要素法シミュレーション

  川村, 洋平, 杉山, 文乃, 倉岡, 千郎

  春季大会講演集. I, 資源編 19 (1) 35 - 36 1343-9898 2007/03/29 [Not refereed][Not invited]
  
• ジャイロ・加速度センサを用いた落石軌跡計測に関する基礎研究

  川村, 洋平, 山近, 哲志, 細川, 雄悟

  春季大会講演集. I, 資源編 19 (1) 33 - 34 1343-9898 2007/03/29 [Not refereed][Not invited]
  
• 超磁歪振動子を用いたコンクリート構造物損傷検査におけるケプストラム解析の適用性

  川村, 洋平, 浅香, 充慶, 河, 宜成, 伊藤, 優, 水谷, 孝一

  春季大会講演集. I, 資源編 19 (1) 17 - 18 1343-9898 2007/03/29 [Not refereed][Not invited]
  
• 超磁歪振動子とデコンボリューションフィルタを用いた地中埋設コンクリートブロック検知

  川村, 洋平, 河, 宜成, 大川, 浩一, 浅香, 充慶, 水谷, 孝一

  春季大会講演集. I, 資源編 19 (1) 15 - 16 1343-9898 2007/03/29 [Not refereed][Not invited]
  
• Correspondence between output of cable censer for vibration detection and physical value

  工藤, 優樹, 川村, 洋平, 大村, 健, 水谷, 孝一, 名和, 豊春

  春季大会講演集. I, 資源編 19 (1) 13 - 14 1343-9898 2007/03/29 [Not refereed][Not invited]
  
• 超音波による新手法を用いた鉱山ヘルメットライト用電池の開発

  中里, 槙吾, 川村, 洋平, 大川, 浩一

  春季大会講演集. I, 資源編 19 (1) 11 - 12 1343-9898 2007/03 [Not refereed][Not invited]
  
• A1 Synthesis of Iron-based Cathode Materials for Lithium Iron Battery using Sonochemical Method

  Okawa Hirokazu, Nakamura Takashi, Nakasato Shingo, Kawamura Yohei, Sato Mineo

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 16 1 - 2 2007 

  The Olivine-type LiFePO_4 was prepared by sonochemical method starting from LiOH・H_2O, (NH_4)_2HPO_4 and FeSO_4・7H_2O. Ultrasonic irradiation upon the solution of raw materials was able to synthesize fine particles of LiFePO_4 and prohibit the conversion of Fe^<2+> to Fe^<3+> in the solution without using a reducing agent. The prepared LiFePO_4 was characterized by XRD and SEM. The shape of the sample was a globular structure and the particle size of that was homogeneous and under sub-micron. The temperature of the solution is an important factor to synthesis LiFePO_4 by the sonochemical reaction. Discharge behavior of LiFePO_4 synthesized sonochemical reaction at 60℃ of the solution temperature exhibited 113mAhg^<-1> in the range of 4.0-3.0V vs. Li/Li^+ at a current rate of 0.2C. The ultrasonic effects on the precipitation of the LiFePO_4 precursor in the solution are very complicated, but one of them may helps nucleation of the LiFePO_4 precursor as a consequence of the collision among solute raw materials.
• 3-03P-16 Seismic Prospection of Ultra-shallow Region in S-wave Reflection Method using Maximum Attenuation Point of Surface Wave(Poster session 3)

  Kamohara Akihiro, Kawamura Youhei, Ha Eui Seong, Okawa Hirokazu, Mizutani Koichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 28 (28) 389 - 390 1348-8236 2007 [Not refereed][Not invited]
  
• 3-03P-15 Proposition of Underground Imaging Method Using Magnified Cross-correlation Analysis(Poster session 3)

  Ha Euiseong, Kawamura Youhei, Okawa Hirokazu, Mizutani Koichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 28 (28) 387 - 388 1348-8236 2007 [Not refereed][Not invited]
  
• 3-02P-12 Fundamental study for Estimation Crack Distribution in Rock Slope Using Giant-Magnetostriction Vibrator(Poster session 3)

  Nakasato Shingo, Kawamura Youhei, Asaka Michinori, Okawa Hirokazu, Mizutani Kouichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 28 (28) 381 - 382 1348-8236 2007 [Not refereed][Not invited]
  
• 2-02P-10 Applicability in Cepstrum Analysis Applied to Non-destructive Testing for Crack of Rock Slope Using Giant-magnetostriction Vibrator(Poster session 2)

  Asaka Michinori, Kawamura Youhei, Nakasato Shingo, Okawa Hirokazu, Mizutani Koichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 28 (28) 213 - 214 1348-8236 2007 [Not refereed][Not invited]
  
• Proposition of Detecting Underground Object using Ultra Shallow Reflection Method based on P-wave Directivity of Giant-Magnetostriction Vibrator

  HA Eui Seong, KAWAMURA Youhei, MIZUTANI Koichi, OKAWA Koichi, ASAKA Michinori

  物理探査学会学術講演会講演論文集 = Proceeding of the SEGJ Conference 115 (0) 261 - 264 2006/10/30 [Not refereed][Not invited]
  
• 落石に作用する衝撃加速度と反発係数の関係

  山近, 哲志, 川村, 洋平, 氏平, 増之, 青島, 伸治

  春季大会講演集. I, 資源編 18 (1) 131 - 132 1343-9898 2006/03/27 [Not refereed][Not invited]
  
• ローテータ方式砕石杭工法を用いた地盤締固め効果の表面波探査による検証

  伊藤, 健, 川村, 洋平, 鈴木, 康雄, 山本, 欣右

  春季大会講演集. I, 資源編 18 (1) 125 - 126 1343-9898 2006/03/27 [Not refereed][Not invited]
  
• 複素ケプストラムを用いた転石の根入れ深さおよび損傷探査

  伊藤, 優, 川村, 洋平, 鶴島, 守, 水谷, 孝一, 倉岡, 千郎, 青島, 伸治, 氏平, 増之

  春季大会講演集. I, 資源編 18 (1) 123 - 124 1343-9898 2006/03/27 [Not refereed][Not invited]
  
• 多気筒ディーゼルエンジン失火気筒判定における回転数の推定

  永山, 誠, 川村, 洋平, 久保, 和良, 氏平, 増之

  春季大会講演集. I, 資源編 18 (1) 45 - 46 1343-9898 2006/03/27 [Not refereed][Not invited]
  
• A6 Synthesis of Iron-based Cathode Materials for Lithium Ion Battery using Sonochemical Method

  Okawa Hirokazu, Nakasato Shingo, Yabuki Junpei, Kawamura Yohei, Arise Ichiro, Uematsu Kazuyoshi, Sato Mineo

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 15 13 - 14 2006 

  At present, lithium cobalt oxides and lithium nickel oxides are mainly used as cathodes of lithium ion batteries. This is because these materials show very high battery performance. However, they are not suitable for large-scaled batteries such as hybrid vehicles, because they are expensive and poor in resources. We then focused on iron because it is cheaper and more abundant. Iron Phosphate (FeO_4) is one of the most interesting materials in Iron based materials so far because it shows a high discharge voltage of 3.5 volts. The theoretical capacity is 170mAh/g, which is sufficient enough compared to present materials being used as lithium ion batteries. The remarkable feature of FePO_4 is that it can be synthesized in air. Its treatment is very easy but the cycle performance shows poor. In this study, we have tried to obtain good cycle performance and improve discharge capacity of FePO_4 utilizing the sonochemical method. The sonochemical reaction was conducted under the irradiation of ultrasound power 200W and frequency 200kHz for 3hours. The crystalline phase was identified by powder X-ray diffraction. The cathode for the electrochemical characterization was made by mixing powders of the sample, acetylene black and PTFE in 70:25:5 weight ratio under Argon atmosphere. The cathode properties were measured in a galvanic cell with a nonaqueous electrolyte, a polypropylene separator and a Li metal anode. Charge/Discharge performances were evaluated at a current rate of 2C in the voltage range between 2 to 3.9 volts. The first discharge profile obtained for the sample heated at 700℃ is improved about 10% compared with a previous report's one. We could also obtain LiFePO_4 by the sonochemical method.
• P18 Synthesis of Fe_3PO_7 Cathode Material for Lithium Iron Battery by Sonochemical Method(Poster Session)

  Nakasato Shingo, Okawa Hirokazu, Kawamura Yohei, Uematsu Kazuyosi, Sato Mineo

  Proceedings of the Annual Meeting of the Japan Society of Sonochemistry 日本ソノケミストリー学会 15 81 - 82 2006 

  Iron is expected as a positive electrode material because of its large Clarke number. In this reason, we have been interesting in iron based materials and been studying. In this time we focused on Fe_3PO_7. The theoretical capacity as cathode is 777mAh/g. Its large capacity is very attractive to compare to present materials being used as lithium ion batteries (LiCoO_2: 274mAh/g, LiMn_2O_4: 148mAh/g). The literature shows that Fe_3PO_7 was prepared by the two-step solid-state reaction. At first stoichiometric amounts of Fe_2O_3 and (NH_4)_2HPO_4 powders are mixed and heated 950 degrees Celsius for 12hour to synthesize FePO_4. Fe_2O_3 and FePO_4 are mixed and preheated 950 degrees Celsius for 12hour and finally heated at 1050 degrees Celsius and finally Fe_3PO_7 is prepared. Fe_3PO_7 requires a lot of time and high sintered temperature. To improve these problems, we have been studying about an easily synthesis method of Fe_3PO_7. In this study, we used the sonochemical method and try to obtain Fe_3PO_7 by one step reaction.
• Verification of an effect of soil densification applying gravel drain system using surface-wave method and DEM simulation

  Youhei Kawamura, Ken Ito, Kinsuke Yamamoto, Tatsuo Sakakibara

  13th International Congress on Sound and Vibration 2006, ICSV 2006 6 4915 - 4922 2006 

  In this research, the validity of soil densification applying gravel drain system was inspected, by practicing a small-scale experiment and a distinct element method simulation. Soil densification applying gravel drain system that was developed by MARUJUN Corporation is one of the effective ways of preventing liquefaction. Because of the peculiarity of the motor, it is possible to hold down the cost, scale and the term of construction compared to conventional methods. Effect of compaction can be expected too, from applying pressure when injecting aggregate from the top. The effect of compaction was verified using surface-wave method. Surface-wave method has been applied to both engineering and earth science problems to image the S-wave velocity of the earth. Surface-wave method can estimate S-wave velocity models that are extremely valuable in geotechnical work. Therefore, surface-wave method has been increasingly used in various civil engineering and environmental investigations. To decide a diameter of auger, distinct clement method (DEM) Simulation was performed. DEM is suitable for the simulation of deformation behavior of a discontinuous model. It assumes that an analysis object is a set of small elements. By solving the equations of motion for each element, behavior of the analysis object is observed. Copyright© (2006) by the International Institute of Acoustics & Vibration.
• Consideration about effectiveness on magnified cross-correlation analysis in frequency domain by detection of underground piping

  Eui Seong Ha, Youhei Kawamura, Koichi Mizutani

  13th International Congress on Sound and Vibration 2006, ICSV 2006 6 4722 - 4729 2006 

  The purpose of this research is to detect underground piping, which are buried under 60 cm to 124 cm from surface using seismic method. Seismic method is generally used to inquire underground condition by receiving the reflection waves. Generally as a seismic source a hammer or gunpowder is used. However they are not capable of generating an arbitrary seismic wave. In this research, as a seismic source giant-magnetostriction vibrator was used. This vibrator can generate an arbitrary elastic wave in various frequency domains. As a conventional method, cross-correlation analysis is applied to distinguish reflection waves and other waves. However it is not sufficient to obtain desirable result. Therefore as a new analysis Magnified Cross-Correlation Analysis in Frequency Domain was proposed. To consider effectiveness of this analysis, the experiments of detecting underground concrete blocks and piping were conducted using that analysis. Concrete blocks and piping are buried underground the depth of 60cm to 124cm from the surface. As a result, the depth of underground piping and concrete blocks were estimated in high precision, and the effectiveness of Magnified Cross-Correlation Analysis in Frequency Domain was confirmed. Copyright© (2006) by the International Institute of Acoustics & Vibration.
• Cepstrum analysis applied to ultrasonic reflection wave detection wave method to investigate the depth and the damage of the pile

  Yu Ito, Youhei Kawamura, Koichi Muzutani, Senro Kuraoka

  2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13 1561 - + 2006 [Refereed][Not invited]
   

  In civil engineering, especially in construction sites, it is essential to investigate the degree of damage and the depth of foundation piles and pillars, Ultrasonic wave and elastic impact wave methods are currently used as typical non-destructive test ing methods to be applied to a concrete object such as a foundation pile for construction. The latter is performed with using a hammer as its input making this method inaccurate and hard to obtain the same result each time. Therefore, ultrasonic measurement method was chosen over elastic impact wave method to be applied in this study. However, by using the conventional ultrasonic measurement method, since the input is very small, the depth of the investigation is very shallow. Therefore, if it becomes possible to input ultrasonic wave vibration into the concrete foundation pile, deeper depth investigation with higher precision will be attained. In this study, ultrasonic reflection wave detection method was used in order to measure the length of the pile and to detect the degree of damage in the pile. © 2006 ICASE.
• Study on estimation of the finite-length unknown input waveform from a given input waveform response

  Yuki Kudo, Nobuharu Aoshima, Youhei Kawamura

  2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13 213 - + 2006 [Refereed][Not invited]
   

  The information obtained by measuring a system can be regarded as a response given by the Black Box when there is an input. In this study, estimation of the finite-length unknown input waveform from a given input waveform response in a second order damped oscillation system is conducted. The theory is shown and verified with the simulation on MATLAB. While the effectiveness of this theory in the real system is shown by carrying out an experiment. The unknown input waveform form is estimated as followed. The impulse response is estimated from the response waveform of the system. Then, Fourier transformation for the response waveform and the estimation waveform of the impulse response was conducted, and the spectrum of the response wave was decided by the spectrum of the estimated impulse response. Lastly, inverse Fourier trans form was conducted to this result. This end result obtained is the estimated waveform of the unknown input waveform. In this experiment, the output waveform of the system was measured with an laser displacement sensor. The result was influenced by the noise, however the input waveform was able to be estimated. © 2006 ICASE.
• Estimation of the engine revolution for statistical analysis of RMS value by using Prony method to detect misfiring cylinder of the diesel engine

  Makoto Nagayama, Youhei Kawamura

  2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13 4016 - + 2006 [Refereed][Not invited]
   

  Mechanical problems with large-scale mining machinery can cause serious losses in operational efficiency and profits. A diesel engine with a misfiring cylinder is likely to break down in a short period of time when the engine is used without maintenance. The authors have developed a new system to detect whether an engine is misfiring and, if so, which cylinder is misfiring. This system will be able to manage the engine from a remote location. In this study, a minimum number of sensors will be applied on two cylinders of the engine in order to detect misfiring cylinder. The measured waveform was analyzed by the statistical analysis of R.M.S value. Dividing up combustion time of each cylinder is the first step for statistical analysis of R.M.S value. In case of idling state of the engine, it is easy to divide up combustion time. But, it is necessary to find engine revolutions under the state of rotational fluctuation of the engine. The period of combustion time vary every hour under the state of rotational fluctuation. Therefore, engine revolutions were computed by using Prony method. The period of combustion time was divided, and R.M.S value was calculated. © 2006 ICASE.
• P2-19 Validation of Effectiveness on Magnified Cross-Correlation Analysis in Frequency Domain based on Directivity of Giant-Magnetostriction Vibrator(Poster session 2)

  Ha Eui Seong, Kawamura Youhei, Mizutani Koichi, Okawa Koichi, Asaka Michinori

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 27 (27) 245 - 246 1348-8236 2006 [Not refereed][Not invited]
  
• P2-18 Detection of Concrete Crack Using Giant-Magnetostriction Vibrator(Poster session 2)

  Kawamura Youhei, Asaka Michinori, Ha Eui Seong, Ito Yu, Okawa Koichi, Mizutani Koichi

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 27 (27) 243 - 244 1348-8236 2006 [Not refereed][Not invited]
  
• Study on the detection of misfiring cylinder in a heavy machinery multi-cylinder diesel engine under the state of rotational fluctuation

  Makoto Nagayama, Youhei Kawamura, Masuyuki Ujihira

  SAE Technical Papers 0148-7191 2006 [Refereed][Not invited]
   

  Mechanical problems of heavy machinery can cause serious losses . And a diesel engine with a misfiring cylinder is likely to break down in a short period of time. In this system, a minimum number of sensors will be installed in the diesel engine to build a diagnosis system which detects anomaly behavior by analyzing the acceleration waveform using statistical analysis of R.M.S. value. This method is superior to traditional methods in point of simplicity, and this system can be applied to the ready-made machinery easily. This system will make it possible to manage the engine from a remote location by data transfer . However, previous system was limited in case of an idling state of the engine. It was successful to detect misfiring condition of cylinder on the engine under the state of rotational fluctuation in this research. Copyright © 2006 SAE International. [1, 2] [3]
• 落石シミュレーションにおけるパラメータ同定を目的とした衝撃加速度の検討

  西山えるむ, 川村洋平, 山近哲志, 齊藤知宏, 氏平増之

  応用力学論文集 土木学会 9 531 - 538 1345-9139 2006 [Refereed][Not invited]
  
• Study on Output Mechanism of Cable Sensor for Vibration Detection

  F.Ito, D.Akhmetov, M.Komazaki, H.Tachikawa, M.Ujihira, K.Ohara;Y, Kawamura, 川村, 洋平

  SICE SICE 41 (9) 2005/09 [Refereed][Not invited]
  
• Ultrasonic measurement system for detecting penetration of boulders by autocorrelation analysis

  Y Kawamura, M Tsurushima, K Mizutani, M Ujihira, N Aoshima, S Kuraoka

  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 44 (6B) 4364 - 4369 0021-4922 2005/06 [Refereed][Not invited]
   

  An elastic impact wave method is used as a typical nondestructive test method to investigate the depth of boulder penetration. However, in the elastic impact wave method using, for example, a hammer, the discrimination of the reflection wave produced by minute cracks is difficult. Theoretically, if it becomes possible to input the vibration of an ultrasonic domain into artificial structures, such as a concrete and a boulder, with a strong amplitude, deeper investigation depth compared to the conventional way with a high precision will be attained. In this study, a concrete block, with a known size, which was, unlike boulders, not buried under ground, was used as a test piece in a basic experiment. As analysis methods, a wavelet analysis for checking the reflection wave and an autocorrelation analysis for identifying the time tag of the reflection wave were used. As a result, the reflection wave was detected in a down chirp signal from 50 kHz to 40 kHz.
• Ultrasonic measurement system for detecting penetration of boulders by autocorrelation analysis

  Y Kawamura, M Tsurushima, K Mizutani, M Ujihira, N Aoshima, S Kuraoka

  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 44 (6B) 4364 - 4369 0021-4922 2005/06 [Refereed][Not invited]
   

  An elastic impact wave method is used as a typical nondestructive test method to investigate the depth of boulder penetration. However, in the elastic impact wave method using, for example, a hammer, the discrimination of the reflection wave produced by minute cracks is difficult. Theoretically, if it becomes possible to input the vibration of an ultrasonic domain into artificial structures, such as a concrete and a boulder, with a strong amplitude, deeper investigation depth compared to the conventional way with a high precision will be attained. In this study, a concrete block, with a known size, which was, unlike boulders, not buried under ground, was used as a test piece in a basic experiment. As analysis methods, a wavelet analysis for checking the reflection wave and an autocorrelation analysis for identifying the time tag of the reflection wave were used. As a result, the reflection wave was detected in a down chirp signal from 50 kHz to 40 kHz.
• 重機用ディーゼルエンジンの失火気筒判定システムにおけるALM解析の改善

  川村, 洋平, 永山, 誠, 氏平, 増之, 伊藤, 史人, ダウレン, アクメトフ, 青島, 伸治

  春季大会講演集. I, 資源編 17 (1) 101 - 102 1343-9898 2005/03/28 [Not refereed][Not invited]
  
• Temperature Measurement in Tunnel Using Acoustic Method

  MIZUTANI Koichi, KASHIWAZAKI Kenichi, ITOGA Kazuya, SAWAMURA Kyohei, KUDO Kousuke, KAWAMURA Youhei

  春季大会講演集. I, 資源編 17 (1) 91 - 92 1343-9898 2005/03/28 [Not refereed][Not invited]
  
• 超音波を用いた転石根入れ深さの探査における反射波検出手法

  川村, 洋平, 鶴島, 守, 水谷, 孝一, 伊藤, 優, 氏平, 増之, 青島, 伸治

  春季大会講演集. I, 資源編 17 (1) 89 - 90 1343-9898 2005/03/28 [Not refereed][Not invited]
  
• 落石に働く衝撃加速度からみた力学モデルの検討

  川村, 洋平, 山近, 哲志, 氏平, 増之, 伊藤, 健, 青島, 伸治

  春季大会講演集. I, 資源編 17 (1) 63 - 64 1343-9898 2005/03/28 [Not refereed][Not invited]
  
• 斜面切削時の崩壊シミュレーション

  川村, 洋平, 伊藤, 健, 山近, 哲志, 氏平, 増之, 青島, 伸治, 榊原, 辰雄

  春季大会講演集. I, 資源編 17 (1) 61 - 62 1343-9898 2005/03/28 [Not refereed][Not invited]
  
• Method of detecting reflection wave using corresponding wave difference analysis for ultrasonic measurement system to detect penetration of boulders

  Mamoru Tsurushima, Youhei Kawamura, Yu Ito, Koichi Mizutani, Senro Kuraoka, Masuyuki Ujihira, Nobuharu Aoshima

  12th International Congress on Sound and Vibration 2005, ICSV 2005 5 4286 - 4293 2005 

  Presently, because of an economic efficiency or usability, nondestructive test is being used to evaluate the damage level and the size of the concrete structure. Ultrasonic and elastic impact wave methods are the current testing methods of nondestructive test. Authors have developed a new testing method which uses chirp signal of ultrasonic and auto-correlation analysis in order to measure the penetration of the boulder stone into the ground. In our past research, we have successfully presumed the length of 900mm long concrete block and the length of 1460mm long white granite almost identically when the AE transducer received the direct wave and the reflection wave separately. However, when the direct wave and the reflection wave were mixed, we were unable to presume the length from the obtained waveform. In this paper, under the obtained data were mixed the direct wave and the reflection wave, the way to read the arrival time of the reflection wave from the data is referred. Authors group invented the way to use difference of the output waveform from two receivers with which the distance from a transmitter differs. And the result of the experiment with the length of 900mm long concrete block is shown.
• Study on ultrasonic measurement system to detect penetration of boulders

  Y. Kawamura, N. Aoshima, M. Tsurushima, Y. Ito, K. Mizutani, M. Ujihira

  Proceedings of the SICE Annual Conference 427 - 432 2005 

  Ultrasonic and elastic impact wave methods are used as the typical prototype of measuring concrete objects without breaking them up. However, by using the ultrasonic method, the input is restricted to be very small. Therefore, only the shallow region of the object can be investigated. Also, it is a tedious job to analyze the reflection wave obtained from the elastic impact wave method because of the minute cracks existing throughout the object. It is also known that this test method might damage the object.• Theoretically, if it becomes possible to input vibration of an ultrasonic domain into a concrete object with a high output directly, the depth of the object will be obtained with high precision. In this research, it is aimed to improve the already built ultrasonic investigation system, which uses the output vibration of the piezo-electric ceramics that is constructed by the arbitrary waveform of the high voltage. Here, the target is the length of a concrete test piece. Auto correlation analysis will be used to obtain the arrival time of the reflection wave (also known as the reflection wave), when the direct wave and the reflection wave are clearly separated and the reflection wave recognizable. However, unwanted mixed reflection waves will be present throughout the result of this procedure with the targeted reflection wave to measure. Therefore, the cepstrum analysis method is used. The cepstrum analysis method makes it possible to disregard the unwanted mixed reflection wave in the system and to only get the arrival time of the reflection wave that has reached the targeted length of the test piece. It is a simple method that is applied to the power spectrum of the targeted wave, by taking the logarithm of it and transforming it to time dimension using the inverse Fourier transform. The end result shows the arrival time of the reflection wave. The targeted length of the test piece can be obtained using the arrival time. © 2005 SICE.
• P3-49 Fundamental Study on Ultrasonic Inspection of Steel Pipe in Complex using Lamb Wave

  Kawamura Youhei, Noro Kosuke, Ko Takanari, Mizutani Koichi, Aoshima Nobuharu

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 26 (26) 437 - 438 1348-8236 2005 [Not refereed][Not invited]
  
• P3-46 Accuracy improvement of complex cepstrum analysis for detecting penetration boulders using ultrasonic

  Tsurushima Mamoru, Kawamura Youhei, Ito Yu, Mizutani Koichi, Ujihira Masuyuki, Kuraoka Senro, Aoshima Nobuharu

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 26 (26) 431 - 432 1348-8236 2005 [Not refereed][Not invited]
  
• P3-45 Study on Detecting Underground Piping using Giant-Magnetostriction Vibrator

  Kawamura Youhei, Ko Takanari, Noro Kosuke, Mizutani Koichi, Aoshima Nobuharu

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 26 (26) 429 - 430 1348-8236 2005 [Not refereed][Not invited]
  
• Study of improving the ultrasonic measurement system to detect penetration of boulders using the cepstrum analysis

  Youhei Kawamura, Mamoru Tsurushima, Yu Ito, Nobuharu Aoshima, Koichi Mizutani, Senro Kuraoka, Masuyuki Ujihira

  12th International Congress on Sound and Vibration 2005, ICSV 2005 5 4302 - 4309 2005 [Refereed][Not invited]
   

  Ultrasonic and elastic impact wave methods are used as the typical prototype of measuring concrete objects without breaking them up. However, by using the ultrasonic method, the input is restricted to be very small. Therefore, only the shallow region of the object can be investigated. Also, it is a tedious job to analyze the reflection wave obtained from the elastic impact wave method because of the minute cracks existing throughout the object. It is also known that this test method might damage the object. Theoretically, if it becomes possible to input vibration of an ultrasonic domain into a concrete object with a high output directly, the depth of the object will be obtained with high precision. In this research, it is aimed to improve the already built ultrasonic investigation system, which uses the output vibration of the piezo-electric ceramics that is constructed by the arbitrary waveform of the high voltage. Here, the target is the length of a concrete test piece. However, unwanted mixed echoes will be present throughout the result of this procedure with the targeted echo to measure. Therefore the cepstrum analysis method is chose to be used. The cepstrum analysis method makes it possible to disregard the unwanted mixed echoes in the system and to only get the arrival time of the echo that has reached the targeted length of the test piece. It is a simple method that is applied to the power spectrum of the targeted wave, by taking the logarithm of it and transforming it to time dimension using the inverse Fourier transform. The end result shows the arrival time of the echo. The targeted length of the test piece can be obtained using this arrival time.
• Study on the improvement of the credibility of rockfall simulation -direct measurement of acceleration applied to rockfalls

  Satoshi Yamachika, Youhei Kawamura, Masuyuki Ujihira, Nobuharu Aoshima

  Proceedings of the 14th International Symposium on Mine Planning and Equipment Selection, MPES 2005 and the 5th International Conference on Computer Applications in the Minerals Industries, CAMI 2005 1403 - 1413 2005 [Refereed][Not invited]
   

  For pertinent countermeasure of rockfalls, rockfall simulation was studied many times. Any rockfall simulation has not gotten consistency between the simulation result and real rockfall. There are a few causes. One is whether method of calculation used the simulation approaches the mechanics of real rockfall. Two is whether parameters using the calculation are assigned pertinent value. This study suggests direct measurement of rockfall's detail motion which as method of closuring of the problems. It would be possible to determine pertinent value in parameter by comparing the detail motion to calculation result. In this research, 3-demensional rockfall simulation developing in this laboratory is explained. Then the results of experiments on impact acceleration that applies to rockfalls are shown, and compared to calculational results obtained by collision model using this simulation.
• DEM simulation of collapse in cutting of slopes

  Youhei Kawamura, Ken Ito, Tatsuo Sakakibara, Masayuki Ujihira, Nobuharu Aoshima

  Proceedings of the 14th International Symposium on Mine Planning and Equipment Selection, MPES 2005 and the 5th International Conference on Computer Applications in the Minerals Industries, CAMI 2005 606 - 615 2005 [Refereed][Not invited]
   

  The slope loses its stability in the process of cutting it, therefore causing the slope to collapse. The slope is cut when activities such as mining, civil work and removal of deposit are done. The slope collapse triggers dangerous accidents. In 1999, an accident of a mining face slope collapse have occurred in Yunicho, Hokkaido and a machinery operator lost his life. The gavel pit where this slope collapse occurred has a mined out area which is reclaimed during the winter season. In the process of reclamation of the mined out area, a lot of snow was mixed with backfill. It seemed that the slope collapse was caused by the water pressure of melted snow and the difference of density between the reclaimed area and the slope. In this research, it is aiming to identify the behavior and mechanism of the slope collapse using distinct element method (DEM). The slope collapse behavior caused by the difference of gravel properties was reproduced using by changing parameters of elements in the reclaimed area.
• 超音波を用いた杭長探査に関する研究

  鶴島守, 川村洋平, 伊藤優, 氏平増之, 水谷孝一, 倉岡千郎, 青島伸治

  応用力学論文集 土木学会 8 951 - 958 1345-9139 2005 [Refereed][Not invited]
  
• 落石に働く衝撃加速度計測による落石シミュレーションの改善

  山近哲志, 川村洋平, 氏平増之, 伊藤健

  応用力学論文集 土木学会 8 531 - 538 1345-9139 2005 [Refereed][Not invited]
  
• APPLICABILITY OF WAVELET ANALYSIS FOR THE DETECTION OF MISFIRING CYLINDER OF THE DIESEL ENGINE FOR CONSTRUCTION

  KAWAMURA Youhei, UJIHIRA Masuyuki, AOSHIMA Nobuharu, ITO Fumito, AKHMETOV Daouren

  Doboku Gakkai Ronbunshu 公益社団法人 土木学会 0 (763) 107 - 117 0289-7806 2004/06/20 [Refereed][Not invited]
   

  Big scale construction machinery is absolutely necessary for the mineral resources development and various construction works. Troubles of the machinery give serious losses in the efficiency of operations and also in financial proceeds. From a practical point of view, we employed a wavelet transform with Gabor function as a window and analyzed the acceleration wave curves data to detect a misfiring cylinder from the multi-cylinders diesel engine. The results by wavelet analysis revealed that the misfiring cylinder could be detected visually in time-frequency maps. With the aid of statistical analysis using rms value, the misfiring cylinder of multi-cylinders diesel engine can, therefore, be doubly checked by wavelet analysis.
• Study on the Scale Measurement of Objects Lying on a Slope Using Photographed Image : Method of Scale Correction Considering Slope Angle

  UJIHIRA Masuyuki, NAKAJIMA Ippei, KAWAMURA Youhei, KAWAKITA Minoru

  Journal of the Japan Society of Engineering Geology 一般社団法人日本応用地質学会 45 (1) 13 - 21 0286-7737 2004/04/10 [Refereed][Not invited]
   

  It is available to measure the scale of objects applying magnification equation of lens for a photographed image, when the objects are lying in a distant place or too dangerous to access to the places. In practical cases, accurate scale of object can not be measured correctly when only the magnification equation of lens is applied simply to an image, because objects both lying in near place and distant place are photographed in the same frame. Here, method of scale correction was studied initially, because the way of scale correction itself considering slope angle was necessary to calculate the correct lengths of photographed objects. Then, validity of the scale correction method considering slope angle was examined, applying this method to an object model of hexagonal shape on a slope, distributed rocks on a flat board and excavated rocks by blasting. From these examinations, it was confirmed that corrected rate on the scale of hexagonal model was 0.85-1.04 and the rate on the distribution characteristic value of excavated rocks by blasting was 0.94. This correction method is considered to be available for the scale measurement using a photographed image.
• ALMによる大型建設機械用ディーゼルエンジンの失火気筒判定システムに関する研究

  川村, 洋平, アクメトフ, ダウレン, 氏平, 増之, 石川, 達也, 樋口, 澄志

  春季大会講演集. I, 資源編 16 (1) 75 - 76 1343-9898 2004/03/29 [Not refereed][Not invited]
  
• Remote Precautionary Diagnosis of Misfiring Cylinder of the Diesel Engine for Heavy Excavation Machinery Using Mobile Multimedia Network

  KAWAMURA Youhei, UJIHIRA Masuyuki, AOSHIMA Nobuharu, ITO Fumito, AKHMETOV Daouren F.

  Transactions of the Society of Instrument and Control Engineers 公益社団法人 計測自動制御学会 40 (2) 257 - 266 0453-4654 2004/02/29 [Refereed][Not invited]
   

  A diesel engine with a misfiring cylinder is likely to break down in a short time when the engine is used without maintenance. The authors have developed a method of detecting the occurrence of cylinder misfiring and specifying the misfiring cylinder by using wavelet analysis and statistical analysis on the r.m.s. values of two kinds of acceleration waveforms. This detection method is considered superior to traditional methods, which require several accelerometers, especially in terms of simplicity. Since the devolopment of the method, research has been conducted on semi-automatic processing of measured signals and signal transmission from the worksite to a remote office. Field tests confirmed that 1×10⁵ points of dynamic data could be transmitted through the mobile multimedia network within 15min, and the time for signal processing was within 15min. Final determination on the condition of a diesel engine in heavy machinery could be achieved within 30min. Shortened processing time is expected by improvement of the processing software.
• Study on the detection of misfiring cylinder in a shipping multi cylinder diesel engine using aggregative learning method

  Y. Kawamura, M. Ujjhira, M. Nagayama, N. Aoshima, F. Ito, D. Akhmetov

  Proceedings of the SICE Annual Conference 153 - 156 2004 [Refereed][Not invited]
   

  In this study, a minimum number of sensors will be applied on the side of two cylinders on the diesel engine in order to build an abnormal diagnosis system which detects anomaly behavior at an early stage by analyzing the acceleration waveform using the ALM method. This measurement system can be applied to the ship afterwards and by using the satellite phone system to transfer the data, it will be possible to manage the state of the engine from an office on land without the usage of a personal computer system on board.
• Fundamental Study on Ultrasonic Measurement System to Detect Penetration of Boulders Using Auto-correlation Analysis

  Youhei Kawamura, Mamoru Tsurushima, Nobuharu Aoshima, Koichi Mizutani

  IECON 2004: 30TH ANNUAL CONFERENCE OF IEEE INDUSTRIAL ELECTRONICS SOCIETY, VOL 2 2 1795 - 1798 1553-572X 2004 [Refereed][Not invited]
   

  Generally, in the estimation of damage and the investigation of the size of every concrete artificial structure thing, nondestructive test is used. An ultrasonic method and an elastic impact wave method are mentioned to the typical thing of a nondestructive test method. The authors have developed a new ultrasonic method by using ultrasonic wave of the chirp signal and auto-correlation analysis. In this paper, the experiment is separated Pattern 1 and Pattern 2. In Pattern 1, ultrasonic transfer characteristics were investigated for concrete blocks. It was confirmed that the frequency components of 40-60kHz had a good permeability with each thickness of concrete blocks. In Pattern 2, experiment of receiving the reflection wave was carried out using concrete block with width of 900mm and ultrasonic wave of the chirp signal. Reflection wave was detected in the down chirp signal from 50kHz to 40kHz. And the length of concrete block was calculated using auto-correlation was set to 898.156mm. Like this, the good result that have little error could get it using this system. © 2004 IEEE.
• C-2 Fundamental Study using Ultrasonic Measurement System to Detect Penetration of Boulders

  Kawamura Youhei, Tsurushima Mamoru, Mizutani Koichi, Kuraoka Senro, Aoshima Nobuharu

  Proceedings of Symposium on Ultrasonic Electronics 特定非営利活動法人 超音波エレクトロニクス協会 25 (25) 143 - 144 1348-8236 2004 [Not refereed][Not invited]
  
• Study on the Rock Fall Detection System using Steel Wire Cable Sensor and Satellite Phone : Experimental Results on the Applicability for a Cropped Slope

  ITO Fumito, UJIHIRA Masuyuki, YASUIKE Masayuki, KAWAMURA Yohei, HIGUCHI Kiyoshi, YAMADA Takashi, AKHMETOV Dauren F., KOMAZAKI Masaaki

  Journal of the Japan Society of Engineering Geology 一般社団法人日本応用地質学会 44 (4) 223 - 233 0286-7737 2003/10/10 [Refereed][Not invited]
   

  Results of geo-engineering monitoring by Monma et al. at Amatori-hashi, West Area, Wakayama, Japan, have shown that the frequency of various scale rock falls tends to increase just before a big rock fall or a slope failure. This phenomenon has been also observed just before 2nd slope failure following the 1st failure in 1997 at No. 2 Shiraito Tunnel, Hokkaido, Japan. The authors propose the frequency monitoring of small rock falls as a useful way to predict large-scale rock falls or slope failures. In this study, practical applicability of rock fall detection system using steel wire cable sensor and satellite phone was carried out. From this field study the following points were made clear: 1) the proposed system is able to transmit the measured rock fall signals to a remote office. The rock fall frequency and the rock fall source could be evaluated, even when the steel wire cable sensor was stretched on the cropped slope having no net, which made easy the propagation of the rock fall impact. 2) It was confirmed that rock fall characteristics, such as the falling velocity, could be evaluated through analysis of the data registered by the field side personal computer. 3) As a result of composition study of measured waveforms, it was concluded that stretching interval of steel wire cable sensors could be increased up to 10m without deterioration of the system rock fall detection abilities.
• On Signal Transmission and Data Processing Rate for Remote Diagnosis of Heavy Excavation Machinery

  Y. Kawamura, M. Ujihira, K. Higuchi, M. Komazaki, D. F. Akhmetov, F. Ito

  Australasian Institute of Mining and Metallurgy Publication Series (1) 251 - 256 2003 [Refereed][Not invited]
   

  A diesel engine with a misfiring cylinder is likely to break down in a short time when the engine is used without maintenance, The authors have developed a method of detecting the occurrence of cylinder misfiring and specifying the misfiring cylinder by using wavelet analysis and statistical analysis on the root mean square (r.m.s.) values of two kinds of acceleration waveforms. This detection method is considered superior to traditional methods, which require several accelerometers, especially in terms of simplicity. Since the development of the method, research has been conducted on semi-automatic processing of measured signals and signal transmission from the worksite to a remote office. Field tests confirmed that 1 × 10 points of dynamic data could be transmitted through the mobile multimedia network within IS minutes, and the time for signal processing was within 15 minutes. Final determination on the condition of a diesel engine in heavy machinery could be achieved within 30 minutes. Shortened processing time is expected by improvement of the processing software. 5
• Artificial Neural Network Approach for Evaluation of Weight of Fallen Objects

  F. Ito, D. F. Akhmetov, M. Komazaki, M. Yasuike, Y. Kawamura, M. Ujihira

  Australasian Institute of Mining and Metallurgy Publication Series (1) 47 - 53 2003 [Refereed][Not invited]
   

  Remote monitoring of geological situation at distant regions with complicated relief, including reliable detection of the rock falls and estimation of the scale of accidents, is of great importance for practical needs. In the paper, vibration data, caused by fall of sample objects and registered by cable sensors, are processed and analysed in order to construct some measure for the indirect evaluation of weight of fallen objects. Nonlinear models, which based on artificial neural networks (ANN), are proposed for the signal presentation. To improve and simplify the learning and classification abilities of the whole system, the aggregative learning method (ALM) is implemented. ALM features relatively low memory and computational resources needed for the procedure realisation, especially for data classification (recall) stage, in compare to conventional methods. The validity and efficiency of the proposed approach are tested through its application for rock fall detection and weight evaluation system using cable sensors and mobile communication network. Classification abilities of the proposed approach are shown useful for estimation of the fallen object weight. Characterised with high computational efficiency and simple decision-making procedure, the derived method can be useful for simple and reliable real-time monitoring system design.
• Applicability of the magnification equation of lens for slope survey

  M. Ujihira, T. Hzuka, Y. Kawamura, M. Kawakita

  International Journal of Surface Mining, Reclamation and Environment 16 (3) 230 - 244 1389-5265 2002/09 [Refereed][Not invited]
   

  Photography is often used in geological survey, mining engineering or civil engineering to measure the length or width of an object by placing another object such as a scale, a hammer or a cigarette box next to the object. But, it is difficult to place a scale nearby the object when the object is too far and high or too dangerous to get to. In this study, practical applicability of the magnification equation of lens for indirect calculation of the length of a photographed object was examined. From this study, it was found that the applicable distance for the use of the magnification equation of lens was 84 m, even when the focal length was 36mm, and that the applicable distance was more than 300 m with the lens focal length being longer than 100 mm. Moreover, falling behavior, impact load and energy of a rock fall could be calculated readily using obtained information from a photograph.
• Study on the Detection of Misfiring Cylinder in a Multi-Cylinder Diesel Engine Loaded on the Practical Machinery

  KAWAMURA Youhei, UJIHIRA Masuyuki, KIRIMOTO Kenta, OGATA Sumitoshi, NAKAMURA Shouichi, HIGUCHI Kiyoshi

  Shigen-to-Sozai 一般社団法人 資源・素材学会 118 (5) 399 - 406 0916-1740 2002/06/25 [Refereed][Not invited]
   

  As a motive power in heavy construction machineries including mining and various construction works, a multi-cylinders type of diesel engine is very often used because of its high cost performance. Steady maintaining of diesel engine's operation is substantial in view of economic demands and environmental concerns. To realize this, a practice of early diagnosis and early repair are essential.
  In our previous study using a V-12 type of diesel engine installed on a bench, we demonstrated that a misfiring cylinder could be detected by statistical analysis method using rms value of the acceleration waveforms measured on a single point of the engine block.
  In this paper, the same experimentation and analyses as in the previous study were conducted for two practical machineries that loaded the same type engine of the previous study. Even though the engine was loaded on a practical machinery, it was found that a misfiring cylinder could be detected by the same way as in the previous study. In addition to the analyzing method in the previous study, in this study, we employed a wavelet transform method with the Gabor function as a window, and analyzed the acceleration waveforms. The results of wavelet analysis revealed that a misfiring cylinder could be detected visually from time-frequency charts. With the aid of statistical analysis using rms value, a misfiring cylinder in a multi-cylinder diesel engine can be doubly checked by wavelet analysis.
• Study on the Utilization of Magnification Equation of Lens for the Scale Measurement of an Object in a Long Distance

  UJIHIRA Masuyuki, IIZUKA Takehiko, KAWAMURA Youhei, KAWAKITA Minoru

  Journal of the Japan Society of Engineering Geology 一般社団法人日本応用地質学会 43 (1) 2 - 13 0286-7737 2002/04/10 [Refereed][Not invited]
   

  Photograph is often used in geological survey to measure the length or width of a snapped object, placing some scales such as scale itself, a hammer or a cigarette box nearby the object. However, it is difficult to place a scale nearby the object when the object is too far and high from the taking point or too dangerous to get to the object. In this study, practical applicability of magnification equation of lens for indirect calculation of the length of an object was examined. From this study, following points were made clear (1) Upper limit of applicable distance of magnification equation of lens is more than 300m when the lens whose focal length is longer than 100mm is used. (2) Distortion of a snapped image is within 1.0-2.0%, when the lens whose focal length is longer than 100mm is used. (3) Distortion of a snapped image can be revised using the relationship between the displacement from the correct point and radius from the optical axis. (4) Indirect scale measurement method of a long distant object using a camera and a non-prism razor telemeter is useful. However, accurate measurement of the distance, use of a lens of accurate focal length and accurate measurement of the snapped image on a film are absolutely necessary.
• Precautionary Diagnosis of Burning Conditions of a Diesel Engine Equipped with Dozen Cylinders for Construction Machinery

  KIRIMOTO Kenta, KAWAMURA Youhei, UJIHIRA Masuyuki, OGATA Sumitoshi

  計測自動制御学会論文集 計測自動制御学会 38 (2) 230 - 232 0453-4654 2002/02/28 [Refereed][Not invited]
  
• 振動解析による建設機械エンジンの不燃気筒の検出

  桐本賢太, 川村洋平, 氏平増之, 緒方純俊

  電気学会計測部会論文集 01 (53) 29-34  2002 [Refereed][Not invited]
  
• A Study on Practical Applicability of Steel Wire Cable Sensor for a Real Slope

  KOMAZAKI Masaaki, URATA Kenji, ITO Fumito, UJIHIRA Masuyuki, TOKUNAGA Tetsuaki, KONNO Shinya, KAWAMURA Youhei, HIGUCHI Kiyoshi, KAWAKITA Minoru

  Journal of the Japan Society of Engineering Geology 一般社団法人日本応用地質学会 42 (5) 264 - 273 0286-7737 2001/12/10 [Refereed][Not invited]
   

  The authors have been studying a cable sensor based monitoring system for rock fall detection. The tensile strength of cable sensor (CS) is low and not sufficient for usage under real environment conditions. For this reason, steel wire type cable sensor (SWCS) is proposed with the cable sensor coaxially rolled in steel wire. Here, results of a field test, with SWCS installed on a slope, are presented and the following points are made clear.
  1). An accelerometer was installed on SWCS, and experiment on sensitivity analysis was performed in which the sensors were excited by blowing their neighborhood. It was shown that there was an exponential dependence between the output voltage of the SWCS and the accelerometer output. The derived equation is possible to transform the output signal of the SWCS into the output signal of the accelerometer, and the sensitivity difference of the sensors could be eliminated. 2). The desired output voltage of SWCS, installed in a grid pattern on a real slope, was gained after amplification with rate of 2. There is a time lag between output voltage waveform of different channels caused by the rock dropped from the upper point of the slope. The analysis of the time lag and the output waveform provides the possibility of the fallen rock behavior monitoring, including jumps, crashes, tracking. The visual pattern of the fallen rock behavior is reconstructed using topographical representation. 3). The analysis of the curve, connecting the initial points of the SWCS output waveforms, provides an information about falling process parameters (velocity coefficient, friction coefficient, the rock fall velocity at the slope foot, kinematical energy). These parameters are valid for design of protective constructions. Also, the SWCS, being used for the long-term monitoring, can be of practical use for large-scale rock fall prediction by measurement of the current frequency of the small rock falls.
• A Study on the Detection of Non-combustion Cylinder of the Diesel Engine for Construction Machinery - An application of rms analysis of acceleration waves -

  KAWAMURA Youhei, UJIHIRA Masuyuki, HIGUCHI Kiyoshi, NAKAMURA Syouichi, KOMAZAKI Masaaki, ITO Fumito

  Shigen-to-Sozai 一般社団法人 資源・素材学会 117 (6) 485 - 493 0916-1740 2001/06/25 [Refereed][Not invited]
   

  Big scale construction machinery is absolutely necessary for the mineral resources development and various construction works. Troubles of the machinery give serious losses in the efficiency of operations and also in financial proceeds. In this meaning, machinery maintenance is very important for mining and construction works. Early diagnosis of the machinery is especially important to prevent a serious damage. Recently, diesel engine applied to excavation machinery are highly improved not to discharge exhaust gases of high concentration and to achieve high energy efficiency. However, a diesel engine involving non combustion cylinder has high probability to breakdown in a short time when the engine is used without any maintenance works.
  In this study, autocovariance of acceleration waves of cylinder block was calculated to obtain the period of revolution, and the combustion period of each cylinder was determined. Then rms value corresponding to each combustion period was calculated. Probability of overlapped area of two curves of normal distribution, which were obtained from rms values of normal and non combustion states respectively, was calculated. It was confirmed that non combustion cylinder of a diesel engine of V-12 type could be judged clearly using the relative intensity curve of the probability. This judgement method is considered to be superior to traditional methods where more than several numbers of accelerometers were used, especially from the viewpoint of simplicity.
• Comparative Study on the Output Characteristics of Steel Wire Cable Sensor

  UJIHIRA Masuyuki, KAWAMURA Youhei, HIGUCHI Kiyoshi, SATOH Masashi, KONNO Hisashi, KOMAZAKI Masaaki, ITO Fumito

  Journal of the Japan Society of Engineering Geology 一般社団法人日本応用地質学会 42 (1) 15 - 23 0286-7737 2001/04/10 [Refereed][Not invited]
   

  It is considered that cable sensor for vibration detection is useful, for instance, to detect the rock falling or small failures of a slope before the occurrence of a big failure. The original cable sensor is susceptible to be yielded by the tensile force, because whose tensile strength is not so enough (40 to 50 kgf). Authors have developed the steel wire cable sensor in which original cable sensor is placed instead of the string of hemp in the central portion. It was necessary to test the sensitivity of this remodeled steel wire cable sensor. As a result of the sensitivity test, following points were clarified: 1) Sensitivity of the steel wire cable sensor does not decrease when the sensor is fixed rigidly or glued continuously to the surfaces of stiff structure made of concrete or steel. 2) Sensitivity of the steel wire cable sensor decreases to 60% against the output of original cable sensor when the cable sensor is buried in the soft land. However, it was confirmed that output level was enough to use practically. In conclusion, the steel wire cable sensor could be used practically to various places to detect vibrations.
• Practical applicability of steel wire cable sensor for rock fall detection

  M Ujihira, F Ito, T Tokunaga, Y Kawamura, S Konno, K Higuchi, M Komazaki

  MINE PLANNING AND EQUIPMENT SELECTION 2001 57 - 62 2001 [Refereed][Not invited]
   

  Authors have studied the rock fall prediction system for these several years, in which cable sensor for vibration detection and mobile multimedia network are applied. It was confirmed from field tests that the newly developed steel wire cable sensor, which was installed along an unstable slope in grid pattern, could detect the falling impact even when the weight of a block was 200g and the falling trajectory could be judged from the gap of rise time of wave forms of 9 strings of the sensors stretched in horizontal direction. Topographic figure which was drawn by using the products of amplitudes of wave forms of horizontal and longitudinal steel wire cable sensors could give the falling trajectory visually. We have concluded that the steel wire cable sensor was useful to monitor the instability of the slope.
• Evaluation of the weight of fallen object using the wave forms measured by cable sensor and mobile multimedia network system

  F Ito, S Tsukazawa, M Komazaki, M Ujihira, Y Kawamura, T Tokunaga

  MINE PLANNING AND EQUIPMENT SELECTION 2001 755 - 760 2001 [Refereed][Not invited]
   

  Frequency monitoring of small rock fall events is a strong method to predict a slope failure or a rock fall of big scale along the slopes of traffic route and open pit mine. As a monitoring system, authors have proposed a remote monitoring system using cable sensor and mobile multimedia network. Frequency distribution or accumulated curve of rock fall events can be monitored using this system. However, it was very difficult to evaluate the weight of a fallen rock of each event, although the scale of the rock fall could serve us the important information to predict the failure in succession from the rock fall event. For the evaluation of the rock fall scale preceded a slope failure, authors had discussed and judged that wave forms measured by the detection system should be analyzed not only by using amplitude characteristics of output wave forms but also by using the spectrum characteristics in frequency domain. In this paper, it is described that integrated Fourier spectrum and integrated wave forms of acceleration and output voltage of cable sensor are particularly useful to evaluate the weight of fallen object.
• A study on the detection of non-combustion cylinder of the diesel engine for construction machinery using wavelet analysis

  Y Kawamura, M Ujihira, K Higuchi, K Kirimoto, M Komazaki, F Ito

  MINE PLANNING AND EQUIPMENT SELECTION 2001 167 - 172 2001 [Refereed][Not invited]
   

  A diesel engine involving non-combustion cylinder has high probability to bred in a short time when the engine is used without any maintenance works. In this study, r.m.s. value corresponding to each combustion period of cylinders of diesel engine was calculated. Probability of overlapped area of two curves of normal distribution, which were obtained from r.m.s. values of normal and non-combustion states respectively, was calculated. It was confirmed that non-combustion cylinder of a diesel engine of V-12 type could be judged clearly using the relative intensity curve of the probability. Moreover, wavelet analysis for acceleration wave curves was carried out. It is concluded that almost of all non-combustion states of cylinders could be detected, also performing wavelet analysis for acceleration wave curves of cylinder block.
• 時間周波数解析による重機エンジンの診断

  桐本賢太, 川村洋平, 氏平増之, 緒方純俊

  電気学会計測部会論文集 00 (42) 13-18  2001 [Refereed][Not invited]
  
• Field Study on the Rock Fall Detection System Using Cable Sensor and ovile Multimedia Network for a Rock Shed of Practical Scale

  KOMAZAKI Masaaki, HIRAMA Kazuo, ITO Fumito, UJIHIRA Masuyuki, SUZUKI Shingo, KAWAMURA Youhei, HIGUCHI Kiyoshi

  Journal of the Japan Society of Engineering Geology 一般社団法人日本応用地質学会 41 (4) 200 - 209 0286-7737 2000/10/10 [Refereed][Not invited]
   

  Cable sensor is considered to have a distinctive characteristic to be able to extend a monitoring area for rock failure or rock fall detection. In this study, it was studies if the impact point of fallen rock to rock shed could be evaluated two dimensionally and if the weight of a fallen rock could be evaluated from the measured signals, and characteristics of wave forms of cable sensor was analyzed comparatively with those of accelerometer. Where, cable sensors of 21 strings were stretched in grid pattern of the internal surface of a rock shed of practical scale. Moreover, functions of newly developed signal transmission system using mobile multimedia network was examined. From these field studies, following points have been made clear:
  1) Cable sensor can be used insted of accelermeter for rock failure and rock fall detection when high accuracy in not required. 2) Impact point caused by a weight dropping can be evaluated from rise time of wave forms, from amplitudes of wave forms and also from topography drawn using peak values of wave forms. 3) Order of the weight can be estimated from the amplitude of wave forms. 4) Sensitivity decreases when the length of a cable sensor becomes longer than several meter. But it was confirmed that enough sensitivity could be obtained when the length was longer than 100m. 5) It can be said that signal transmission system using mobile multimedia network can be used practically, because data transmission time from the impact initiation to the final displays of transmitted wave forms and topography on a remote computer is within only three minutes.
• Practical applicability of steel wire cable sensor for rock fall detection

  M Komazaki, K Hirama, F Ito, M Ujihira, Y Kawamura, T Tokunaga

  MINE PLANNING AND EQUIPMENT SELECTION 2000 309 - 313 2000 [Refereed][Not invited]
   

  Authors propose a monitoring system using cable sensor for rock collapse and fall detection. Practical applicability of this prediction system for concrete structures such as rock-shed or inlets of tunnels had been already confirmed, stretching the sensors in grid pattern to the internal surface of the structures. The tensile strength of cable sensor (CS) is 40 - 50 kg, and not enough for usage under real environmental conditions. For this reason, a steel wire type cable sensor (SWCS) is proposed. Here, a field test of SWCS for practical applicability for rock fall detection was carried out and the following points were made clearly: 1) The output signal level of SWCS is lower than that of CS. However, the sensitivity of SWCS is enough for practical use. 2) The falling trajectory of a rock was visually estimated from topographic method of the output voltage of SWCS. Therefore, SWCS could be recommended for practical use.
• Practical applicability of steel wire cable sensor for rock fall detection

  M Komazaki, K Hirama, F Ito, M Ujihira, Y Kawamura, T Tokunaga

  MINE PLANNING AND EQUIPMENT SELECTION 2000 309 - 313 2000 [Refereed][Not invited]
   

  Authors propose a monitoring system using cable sensor for rock collapse and fall detection. Practical applicability of this prediction system for concrete structures such as rock-shed or inlets of tunnels had been already confirmed, stretching the sensors in grid pattern to the internal surface of the structures. The tensile strength of cable sensor (CS) is 40 - 50 kg, and not enough for usage under real environmental conditions. For this reason, a steel wire type cable sensor (SWCS) is proposed. Here, a field test of SWCS for practical applicability for rock fall detection was carried out and the following points were made clearly: 1) The output signal level of SWCS is lower than that of CS. However, the sensitivity of SWCS is enough for practical use. 2) The falling trajectory of a rock was visually estimated from topographic method of the output voltage of SWCS. Therefore, SWCS could be recommended for practical use.
• 振動検出用スチールワイヤ型ケーブルセンサの感度特性(共著)

  川村, 洋平

  土木学会北海道支部論文報告集 (56(A)) 204-207  2000 [Not refereed][Not invited]
  
• スチールワイヤ型ケーブルセンサの斜面への適用に関する研究(共著)

  川村, 洋平

  土木学会北海道支部論文報告集 (56(A)) 208-213  2000 [Not refereed][Not invited]
  
• Fundamental Study on the Diagnosis of Diesel Engine of Construction Machinery.

  川村, 洋平

  土木学会北海道支部論文報告集 (56(A)) 296-299  2000 [Not refereed][Not invited]
  
• A field test of a rock fall detection system using cable sensor and mobile multimedia network

  M. Komazaki, K. Hirama, M. Ujihira, S. Suzuki, H. Saeki, Y. Kawamura

  International Journal of Surface Mining, Reclamation and Environment 13 (4) 159 - 163 0920-8119 1999 

  Cable sensor which is usually used for invader inspection of sensitive places such as atomic power stations and other high security buildings is considered to be available for rock noise and impact detection, because the sensor can detect vibration at any point of a string, and can be used with extending more than a hundred meter or more. From a field test using cable sensor and mobile multimedia network, it was found that the impact source caused by a steel ball dropping in the proximity of the sensing cable could be judged clearly from the order of rise time of signals of cable sensors, amplitudes of wave forms of signals and a topography pictured from peak values of signals transmitted by way of mobile multimedia network. This newly developed system is considered to be applicable not only to detect the resultant impact of fallen rocks but also to monitor the noise produced by the fracture of unstable rocks and sounds of falling rocks along a slope.
• Applicability of the equation of image magnification of lens for rock engineering

  M.Ujihira, T.Iizuka, Y.Kawamura, M.Kawakita, T.Tanabe, 川村, 洋平

  Proceeding of '99 Japan-Korea Joint Symposium on Rock Engneering 171-176  1999 [Refereed][Not invited]
  
• Study on output characteristics and mechanical strength of the cable sensor for vibration detection

  M.Ujihira, Y.Kawamura, M.Sato, H.Konno, M.Komazaki, K.Hirama, 川村, 洋平

  Proceedings of the 8^th Int. Symposium on Mine Planning and Equipment Selection 539-544  1999 [Refereed][Not invited]
  
• 連続衝撃測定センターの特性試験とその考察(共著)

  川村, 洋平

  土木学会北海道支部論文報告集 (55(A)) 52-57  1999 [Not refereed][Not invited]
  
• Rock fall detection system using cable sensor and mobile multimedia network

  M Ujihira, S Ogawa, S Suzuki, S Hosoya, H Saeki, M Komazaki, K Hirama, M Kawakita

  MINE PLANNING AND EQUIPMENT SELECTION 1998 13 (4) 151 - 156 1998 [Refereed][Not invited]
   

  Cable sensor which is usually used for invader inspection to the places such as atomic power stations and other buildings is considered to be available for rock noise and impact detection, because the sensor can detect vibration at any point of a string, and can be used with extending more than a hundred meter or more. From a field test using cable sensor and mobile multimedia network, it was found that the impact source caused by a steel ball dropping could be judged clearly from the order of rise time of signals of cable sensors, amplitudes of wave forms of signals and a topography pictured from peak values of signals transmitted by way of mobile multimedia network. This newly developed system is considered to be applicable not only to detect the resultant impact of fallen rocks but also to monitor the fracturing noises of unstable rocks and falling sounds of rocks along a slope.
• 落石検知用ケーブルセンサの経時変化と出力波形の特性(共著)

  川村, 洋平

  実地技術論文報告集 (14) 736-742  1998 [Not refereed][Not invited]
  

MISC

• Construction of deterioration, deformation and environment monitoring system for preventive conservation at Bayon

  川村 洋平, 池田 啓, 宍戸 英彦, 河﨑 衣美, 北原 格, 丸太 寛之, 里 知樹, 松井 敏也  月刊考古学ジャーナル  (736)  29  -34  2020/02  [Not refereed][Not invited]
  
• クラウドソーシングと3次元復元技術による世界遺産の予防的保存

  宍戸 英彦, 河﨑 衣美, 伊藤 豊, 川村 洋平, 松井 敏也, 森嶋 厚行, 北原 格  電子情報通信学会技術研究報告 = IEICE technical report : 信学技報  117-  (443)  77  -82  2018/02
• 2P4-10 The Effect of Temperature in Underground Mining on the Dust Control using Ultrasonic Atomization

  Okawa Hirokazu, Nishi Kentaro, Kawai Naosuke, Kawamura Youhei, Sugawara Katsuyasu  Proceedings of Symposium on Ultrasonic Electronics  36-  "2P4  -10-1"-"2P4-10-2"  2015/11/05
• 3P4-26 Removal of Arsenous Acid from Sulfuric Acidic Solutions using Ultrasound Oxidation and Iron Oxide(Poster Session)

  Okawa Hirokazu, Yoshikawa Tomohiro, Hosokawa Ryota, Hangui Shingi, Matsunuma Takane, Osawa Takahiro, Kawamura Youhei, Sugawara Katsuyasu  Proceedings of Symposium on Ultrasonic Electronics  35-  507  -508  2014/12/03
• 3P4-23 Application of Ultrasonic Atomization for improving dust control in underground mining(Poster Session)

  Okawa Hirokazu, Nishi Kentaro, Kawamura Youhei, Kato Takahiro, Sugawara Katsuyasu  Proceedings of Symposium on Ultrasonic Electronics  34-  475  -476  2013/11/20
• 3Pa4-8 Flotation separation of bitumen from oil sand using ultrasound irradiation and mixed gases in aqueous solution(Poster Session)

  Saito Tomonao, Okawa Hirokazu, Kawamura Youhei, Babadagli Tayfun  Proceedings of Symposium on Ultrasonic Electronics  33-  369  -370  2012/11/13
• Investigation of thermal conductivity and heat characteristics of oil sands using ultrasound irradiation for shortening the preheating time

  Shingo Kamagata, Youhei Kawamura, Hirokazu Okawa, Koichi Mizutani  Japanese Journal of Applied Physics  51-  (7)  07GE03-1  -07GE03-6  2012/07  [Refereed][Not invited]
   

  Oil sands are attractive as an energy resource. Bitumen, which is found in oil sands, has high viscosity, so that it does not flow. Most oil sands are underground and are developed with a method called steam-assisted gravity drainage (SAGD). Hot steam is injected underground to fluidize bitumen and promote its recovery. However, the preheating time is too long. One way of reducing running costs is by shortening the preheating time. Previous studies have found that bitumen can be extracted from oil sands efficiently by applying ultrasonic irradiation, but SAGD was not applied directly in these cases. Thus, the purpose of this study is to apply ultrasonic irradiation to SAGD, thereby shortening the preheating time of oil sands. As a model experiment for SAGD, heat transfer experiments in a sand layer made with Toyoura sand and silicone oil were conducted and the thermal effect with ultrasound was investigated. © 2012 The Japan Society of Applied Physics.
• 1P1-L11 Development of DigBot for Monitoring the Underground Environment(Robotics and Mechatronics for Transportation and Manufacturing Machine)

  HAYASHI Masahiro, MIYACHI Toshiyuki, KAWAMURA Youhei, MURAKAMI Kazutoshi, KATO Yuichi  ロボティクス・メカトロニクス講演会講演概要集  2012-  "1P1  -L11(1)"-"1P1-L11(2)"  2012/05/27  

  A digging robot named "DigBot" has been developed by our laboratory for monitoring the underground environment and exploring the lunar surface. The purpose of this research is to develop the robot which can dig soil and sand automatically. In this proceeding, first, concept of DigBot is shown. As a basic research of developing Digbot, Contra-rotating drill is developed and made for trial purpose. And then digging experiment is carried out for verifying effectiveness through the Contra-rotating drill. It was proved that DigBot possess incomparably more power than ever before.
• The application of sonication for purifying soil contaminated with microorganism

  Takashi Nakamura, Hirokazu Okawa, Ryota Hosokawa, Tomonao Saito, Youhei Kawamura, Katsuyasu Sugawara  Jpn. J. Appl. Phys.  49-  (7)  07HE11-1 - 07HE11-4  2010  [Not refereed][Not invited]
  
• ソノケミストリーを用いたリチウムイオン二次電池用鉄系正極材料の合成

  大川浩一, 川村洋平, 佐藤峰夫  超音波テクノ  21-  (2)  98  -102  2009  [Not refereed][Not invited]
  
• 超音波特殊反応場を利用した懸濁液中微粒子の沈殿方法

  大川 浩一, 中村 貴司, 川村 洋平  ケミカルエンジニヤリング  53-  (5)  375  -379  2008/05
• 会議報告 2007年 第28回超音波エレクトロニクスの基礎と応用に関するシンポジウム(USE 2007)

  狩野 旬, 川村 洋平, 若槻 尚斗  超音波techno  20-  (2)  112  -115,127  2008/03
• 超音波特殊反応場を利用した懸濁液中微粒子の沈殿方法

  大川浩一, 中村貴司, 川村洋平, 菅原勝康  ケミカルエンジニヤリング  53-  (5)  47  -51  2008  [Not refereed][Not invited]
  
• コンビナート配管における超音波検査手法の提案 (特集 最近の非破壊検査)

  川村 洋平  超音波techno  18-  (5)  17  -21  2006/09
• 超磁歪振動子による地中配管の検知システム (特集 最近の非破壊検査)

  川村 洋平, 河 宜成  超音波techno  18-  (5)  6  -11  2006/09
• 非破壊検査 超音波を用いた転石の根入れ深さ探査システムの構築

  川村 洋平  超音波techno  17-  (3)  71  -75  2005/05
• ディーゼルエンジンの異常診断に関する文献の調査研究

  川村 洋平, 氏平 増之, 樋口 澄志  春季大会講演集. I, 資源編  15-  (1)  53  -54  2003/03/27
• 波形解析によるディーゼルエンジンの異常診断に関する基礎研究 : ALMを用いる場合

  石川 達也, ダウレン アクメトフ, 氏平 増之, 川村 洋平, 樋口 澄志  春季大会講演集. I, 資源編  15-  (1)  55  -56  2003/03/27
• ディーゼルエンジンの燃焼異常の判定システムに関する研究

  川村 洋平, 氏平 増之, 石川 達也, 樋口 澄志  春季大会講演集. I, 資源編  14-  (1)  181  -182  2002/03/28
• 採掘機械の振動データの伝送と異常診断処理速度について

  川村洋平  資源 素材2002秋季大会講演論文集  2002
• 北海道の小規模露天掘り炭鉱と生産設備

  氏平 増之, 川村 洋平, 樋口 澄志, 玉置 富康  資源・素材  2001-  257  -260  2001/09/24
• 振動波形の分析による落下物重量の評価に関する研究

  伊藤 史人, 氏平 増之, 川村 洋平, 今野 慎也, 安池 雅之, 樋口 澄志  資源・素材  2001-  395  -396  2001/09/24
• 建設機械用ディーゼルエンジンの不燃気筒の判定に関する研究 : Wavelet 解析を用いた場合

  川村 洋平, 氏平 増之, 樋口 澄志  資源・素材  2001-  14  -14  2001/09/24
• Wavelet解析によるディーゼルエンジンの不燃気筒の判定に関する研究

  川村 洋平, 氏平 増之, 樋口 澄志, 駒崎 征明, 伊藤 史人  一般発表(研究・業績発表)講演要旨集  2001-  (1)  256  -257  2001/03/01
• Burning condition diagnosis of the diesel engine of construction machinery by time-frequency analysis

  KIRIMOTO Kenta, KAWAMURA Youhei, UJIHIRA Masuyuki, OGATA Sumitoshi  電気学会研究会資料. IM, 計測研究会  2000-  (40)  13  -18  2000/10/05
• ディーゼルエンジンの不燃気筒の判定に関する研究

  川村 洋平, 氏平 増之, 樋口 澄志, 中村 祥一, 駒崎 征明, 伊藤 史人  一般発表(研究・業績発表)講演要旨集  2000-  (1)  132  -133  2000/03/29
• スチールワイヤ型ケーブルセンサによる落石検知のフィールド実験

  氏平 増之, 川村 洋平, 徳永 哲信, 駒崎 征明, 伊藤 史人  一般発表(研究・業績発表)講演要旨集  2000-  (1)  204  -205  2000/03/29
• スチールワイヤ型ケーブルセンサの感度に関する実験結果

  氏平 増之, 川村 洋平, 徳永 哲信, 駒崎 征明, 伊藤 史人  一般発表(研究・業績発表)講演要旨集  2000-  (1)  206  -207  2000/03/29
• ケーブルセンサの感度特性に関する研究(その1)

  氏平 増之, 川村 洋平, 佐藤 昌志, 駒崎 征明, 平間 和夫  一般発表(研究・業績発表)講演要旨集  1999-  (1)  227  -228  1999/03

Books etc

• Encyclopedia of Mathematical Geosciences

  (ContributorMining Modeling)
  Springer 2022/07 (ISBN: 9783030260507)
• Dhaka Megacity

  Kawamura,Youhei (ContributorIllustrating Quality of Life (QOL) in Dhaka City Corporation (DCC) area by integrating remote sensing and census data)
  Springer 2013
• よくわかる農業施設学会用語解説集,

  川村,洋平 (Contributor信号処理)
  2012
• ソノケミストリーを用いたリチウムイオン二次電池用鉄系正極材料の合成

  大川浩一, 川村洋平, 佐藤峰夫 (Supervisor)
  超音波TECHNO 2009/03
• 第17回鉱山設計および設備選択に関する国際会議ならびに中国鉱山設計および設備選択に関する展示に参加して

  川村洋平, 島田英樹 (Supervisor)
  岩の力学ニュース 2009/01
• ［研究室/プロジェクト紹介］ 筑波大学 川村研究室－Geo-Sensing－

  川村洋平 (Supervisor)
  計測と制御 2007/10
• 筑波大学 川村研究室-Geo Sensing-

  川村洋平 (Supervisor)
  超音波TECHNO 2007/01
• 超磁歪振動子による地中配管の検知システム

  川村洋平, 河宜成 (Supervisor)
  超音波TECHNO 2006/09
• コンビナート配管における損傷探査

  川村洋平 (Supervisor)
  超音波TECHNO 2006/09
• 2006 SICE-ICASE International Joint Conference, Vols 1-13

  Kudo, Yuki, Aoshima, Nobuharu, Kawamura, Youhei (ContributorStudy on estimation of the finite-length unknown input waveform from a given input waveform response)
  IEEE 2006/01 (ISBN: 9788995003848)
• 2006 SICE-ICASE International Joint Conference, Vols 1-13

  Ito, Yu, Kawamura, Youhei, Muzutani, Koichi, Kuraoka, Senro (ContributorCepstrum analysis applied to ultrasonic reflection wave detection wave method to investigate the depth and the damage of the pile)
  IEEE 2006/01 (ISBN: 9788995003848)
• 2006 SICE-ICASE International Joint Conference, Vols 1-13

  Nagayama, Makoto, Kawamura, Youhei (ContributorEstimation of the engine revolution for statistical analysis of RMS value by using Prony method to detect misfiring cylinder of the diesel engine)
  IEEE 2006/01 (ISBN: 9788995003848)
• 超音波を用いた転石の根入れ深さ探査システムの構築

  川村洋平 (Supervisor)
  超音波TECHNO 2005/05

Presentations

• Proposal of Environmentally Sustainable Mining Development System Utilizing "Smart Mining +"

  Youhei KAWAMURA, Natsuo OKADA

  The 3R International Scientific Conference on Material Cycles and Waste Management（3RINCs 2024）  2024/03
• 北大ー九大 共同資源工学専攻と資源系教育コンソーシアム  [Invited]

  川村 洋平

  「大学院教育改革フォーラム2023」意見交換会  2023/12
• A Magnetic Climbing Robot for Steel Bridge Inspection  [Not invited]

  Kawamura,Youhei

  The 11th World Congress on Intelligent Control and Automation  2014  China
• The application of ZigBee Technology for underground Mine Communication and Monitoring Systems  [Invited]

  Kawamura,Youhei

  Akita University Leading Program 2013 International Workshop  2013/09  日本 秋田  秋田大学
  
• An Investigation of Radio Wave Attenuation for ZigBee Network in Underground Mines  [Invited]

  Kawamura,Youhei

  The 3rd Int. Symposium on Soft Computing and Disaster Control 2013  2013  Indonesia Bali
• Underground Blasting Optimization by Artificial Intelligence Techniques  [Invited]

  Kawamura,Youhei

  The 3rd Int. Symposium on Soft Computing and Disaster Control 2013  2013  Indonesia Bali
• Emergency Management with ZigBee and GIS  [Invited]

  Kawamura,Youhei

  15th International Symposium on Computational Intelligence and Industrial Applications  2012  Japan Sapporo
• Development of DigBot for Monitoring the Underground Environment  [Not invited]

  Kawamura,Youhei

  15th International Symposium on Computational Intelligence and Industrial Applications  2012  Japan Sapporo
• Long-Term Operation of Landslide observation System Using ZigBee Modules  [Not invited]

  Kawamura,Youhei

  The 1st International Workshop on Soft Computing and Disaster Control  2011  Indonesia Srabaya
• Development of DigBot for Surveying the Underground after the Disaster  [Not invited]

  Kawamura,Youhei

  The 1st International Workshop on Soft Computing and Disaster Control  2011  Indonesia Srabaya
• Underground Imaging Method Using Magnified Cross-Correlation Analysis  [Not invited]

  Ha, Euiseong, Kawamura, Youhei, Mizutani, Koichi, Kamohara, Akihiro, Okawa, Hirokazu

  28th Symposium on Ultrasonic Electronics
• 磁着移動機構と磁界解析を用いた鉄道腐食検知センサシステムの開発  [Not invited]

  宇津木隆裕, 川村洋平, 土方大輔

  ____
• 資源開発阻害微生物の超音波処理  [Not invited]

  細川亮太, 斉藤知直, 大川浩一, 川村洋平

  ____
• 弾性波を用いたドリルビットの三次元位置推定法に関する基礎研究  [Not invited]

  川村洋平, 田村潤平, 鎌形真伍, 持地英実

  ____
• ZigBeeを用いた地すべり監視システムの長期運用性の評価・検討  [Not invited]

  川村洋平, 中畑裕也, 蟹江迪子, 倉岡千郎, 大川浩一

  ____
• オイルサンドからのビチューメン回収における超音波利用の検討  [Not invited]

  大川浩一, 斉藤知直, 細川亮太, 川村洋平

  ____
• 超磁歪震源を用いた極浅層領域のインバージョンイメージング  [Not invited]

  川村洋平, 鎌形真伍, 中畑裕也, 大川浩一

  ____
• インバージョンアルゴリズムを用いた地中配管検知, 資源・素材学会  [Not invited]

  川村洋平, 蒲原章裕, 水谷孝一, 大川浩一

  ____
• DIGBOT開発のための二重反転ドリル性能評価  [Not invited]

  阿部亮平, 川村洋平, 松島亘志, 村上和利, 上島和志

  ____
• 比内緑色凝灰岩採石場における課題から開発された資源有効利用技術  [Not invited]

  大川浩一, 中村貴司, 菅原勝康, 川村洋平

  ____
• PVT装置における重油粘度簡易計測手法の開発  [Not invited]

  川村洋平, 安藤寛, 大川浩一, 菅井裕一, 佐々木久郎

  ____
• 地中埋設物検知における楕円軌道輝度値法の有効性の検証  [Not invited]

  蒲原章裕, 川村洋平, 大川浩一, 水谷孝一

  ____
• Zigbeeを用いた斜面ネットワークの構築  [Not invited]

  川村洋平, 駒井雄一, 太田敬一, 倉岡千郎, 大川浩一

  ____
• 磁歪振動子を入力として用いた表面波探査に関する基礎研究  [Not invited]

  蒲原章裕, 川村洋平, 中里槙吾, 大川浩一, 水谷孝一

  ____
• 磁界を用いた土石流中の礫の位置計測システムの提案  [Not invited]

  杉山文乃, 川村洋平, 松島亘志, 倉岡千郎, 大川浩一

  ____
• 楕円軌道輝度値法を用いた極浅層領域映像化手法の提案  [Not invited]

  川村洋平, 蒲原章裕, 大川浩一, 水谷孝一

  ____
• 超磁歪振動子を用いた岩盤亀裂推定に関する研究  [Not invited]

  浅香充慶, 川村洋平, 中里槙吾, 大川浩一, 水谷孝一

  ____
• 地中埋設物検知への震源オフセットによる表面波減衰の利用  [Not invited]

  川村洋平, 蒲原章裕, 河宜成, 水谷孝一, 大川浩一

  ____
• 土石流流下実験における磁界を用いた位置計測システムの提案  [Not invited]

  杉山文乃, 川村洋平, 松島亘志, 倉岡千郎, 大川浩一

  ____
• PVT装置の粘度計測システムに関する基礎研究  [Not invited]

  中里槙吾, 川村洋平, 宮川雄磨, 大川浩一

  ____
• Development of Underground Mine Communication and Monitoring System by Using ZigBee Technology  [Not invited]

  Kawamura,Youhei

  8th Asian Rock Mechanics Symposium  Japan Sapporo  Rock Mechanics
  
• Prediction of Blast-Induced Ground Vibration at a Limestone Quarry and On-Going Project at WASM  [Invited]

  Kawamura,Youhei

  Rock Breakage and Fragmentation Workshop 2014  Indonesia Yogjakarta

Teaching Experience

Mine Geotechnical EngineeringMine Geotechnical Engineering
Rock BreakageRock Breakage
Measurement EngineeringMeasurement Engineering University of Tsukuba
Geo-SensingGeo-Sensing University of Tsukuba

Association Memberships

• THE SOCIETY OF EXPLORATION GEOPHYSICISTS OF JAPAN   ACOUSTICAL SOCIETY OF JAPAN   JAPAN SOCIETY OF CIVIL ENGINEERS   超音波シンポジウム2009   超音波シンポジウム2008   超音波シンポジウム2007   超音波シンポジウム   THE MINING AND MATERIALS PROCESSING INSTITUTE OF JAPAN   The Society of Instrument and Control Engineers   MPES   Mining Education Australia   AusIMM   

Research Projects

• Development of Museum DX Technology for Efficient Utilization of Cultural Heritage Assets

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2023/04 -2028/03 

  Author : 和田 浩, 齋藤 義朗, 川村 洋平, 鳥屋 剛毅, 北原 格
• 地中熱・地下水熱利用による脱炭素型熱エネルギー供給システムの構築

  JST, JICA：SATREPS

  Date (from‐to) : 2021/04 -2027/03
• Development of Rock and Soil Evaluation System by AI Technologies for Accelerating iConstruction and iControl

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2022/04 -2026/03 

  Author : 川村 洋平, 北原 格, 澁谷 長史, 鳥屋 剛毅
• Co-creation of digital twin technology for efficient blasting in the Mining 4.0 era

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2021/10 -2025/03 

  Author : 川村 洋平, 北原 格, 宍戸 英彦, 鳥屋 剛毅, 福田 大祐, 菊池 亮佑, PARK ILHWAN, 謝 淳

   

  本共同研究は、世界の鉱業が目指す“2050年の低炭素型自動化・無人化鉱山操業”を牽引する次世代鉱山デジタルツインテクノロジーを開発するものである。自動化および無人化が最も必要とされる発破現場の切羽と発破起砕物（モックパイル）を対象に、３次元形状復元などの多次元情報処理と深層学習に代表される人工知能を統合することでCyber-Physical Blastingプラットフォームを構築する。その中で多様な発破シミュレーションおよび検証実験を繰り返し、モックパイル粒度分布推定や発破デザインなどの自動化システムを実装することにより、最適発破計画、発破効率向上、生産率向上、生産管理および安全管理を実現とするものである。 本研究チームは、鉱業界で世界随一の規模と研究体制を誇るの研究教育コンソーシアム“Mining Education Australia (MEA)”と関わりが深く、MEAが推し進める“未来のスマートマイニングに資する共同研究”に、本研究の研究成果である高度ICTを導入することで国際共同研究開発を加速・推進する。国内外の先進的な研究者で組織された学際研究チームが、上記コンソーシアムや海外資源採掘企業と緊密に連携しながら研究開発を実施することにより、実用化の先鞭を付けること目指す。 初年度である2021年度は研究スタートにあたり、チーム編成の見直しを図り、鉱業の上流から下流までをカバーできるよう若手研究者を呼び込んだ。結果、6名の若手研究と2名の教授にて共同研究を加速させるチーム構成とした。しかしながらコロナ禍で海外派遣が叶わなかったことから、国内での打ち合わせとZoomを主体としたWeb打ち合わせがメインの活動となった。海外拠点のCurtin大学とは夏期にWebinarを開催し十分な交流を実現した。国内では研究項目である採掘現場に適した多視点画像撮影方式の開発を完了した。
• ドローンの姿勢制御パラメータを活用した三次元風向風速計測装置の開発

  一般財団法人 大成学術財団：大成学術財団 2024年度 研究助成

  Date (from‐to) : 2024/04 -2025/03 

  Author : 川村洋平, 岡田夏男
• Development of Algorithm for Estimating Seismic Damage of Buried Pipelines Using State-Vector Space on Road Surface Ground Failures

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Research (Pioneering)

  Date (from‐to) : 2022/06 -2025/03 

  Author : 庄司 学, 永田 茂, 北原 格, 川村 洋平, 延原 肇, 丸山 喜久, 西尾 真由子
• トンネル掘削現場における非接触湧水量計測技術の開発

  一般財団法人一樹工業技術奨励会：助成金

  Date (from‐to) : 2023/04 -2024/03
• Development of the System of Cumulative Fatigue Estimating for the Art Objects Subject to Vibration During Transport

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

  Date (from‐to) : 2020/04 -2024/03 

  Author : 和田 浩, 川村 洋平, 小西 毅

   

  平面形状と立体計上の代表として、屏風のオリジナルレプリカを用いた加振実験の結果を解析した。加振実験により、周波数毎の振動伝達特性を把握することができた。屏風のレプリカについては、骨下地と呼ばれる基本構造上で生じた振動が表面の和紙にどのように影響するのかについてさらに検証を進めた。検証に必要なシミュレーション解析を実施し、モデル化に向けての準備を開始した。今年度の研究成果については、以下に示す複数の学術会議にて報告することができた。 「施設内での文化財輸送時に台車上で生じる振動への対策」(文化財保存修復学会第42回大会 2020年7月10日)／「美術品レプリカを用いた加振実験について」(日本包装学会第29回年次大会研究発表会 2020年7月15日)／「輸送時に屏風構造を持つ美術品に発生する共振現象に関する基礎的研究」(日本文化財科学会第37回大会 2020年9月5日)／「屏風構造を持つ美術品の振動応答に関する基礎的研究」(日本機械学会2020年度年次大会 2020年9月16日)／「美術品に用いられる包装資材の評価に関する現状と課題」(JPI（日本包装技術協会）北海道支部2020年度包装懇話会 2020年11月25日)
• 資源採掘における掘削異常のAI診断に資する掘削補助装置の開発

  MMCリョウテック株式会社：

  Date (from‐to) : 2022/08 -2023/07
• トンネリングのための岩種のAI判別に資するハイパースペクトル撮影技術の開発

  五洋建設株式会社：

  Date (from‐to) : 2021/11 -2023/03
• ハイパースペクトルと人工知能を活用した岩盤・土壌自動評価装置の開発

  JST：A-Step トライアウト

  Date (from‐to) : 2020/10 -2022/03
• Development of underground drone for tailings dam investigation

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Challenging Research (Exploratory)

  Date (from‐to) : 2018/06 -2021/03 

  Author : KAWAMURA YOUHEI

   

  The aim of this research is to develop underground drone which can investigate the inside of tailing-dam in mine site. This research project had 4-stages.The 1st one was "Development of contra-rotating drill". The 2nd one was "Designing 3-D Snake locomotion thrust mechanism". The 3rd one was "Motor torque optimization by machine learning". The last one was "Validation test with the prototype". The validation test in real sand tank with all implemented prototype has been conducted. As a result, partial optimization of both drilling and trusting were achieved, overall optimization has not been achieved, though. However, it was confirmed that the snake locomotion thrust mechanism had a big potential for free movement in slurry tank.
• ハイパースペクトルカメラに係るデータ分析支援，分析基礎データ取得

  日本工営：

  Date (from‐to) : 2020/04 -2021/03
• AIによるトンネリング技術の開発

  鹿島建設：

  Date (from‐to) : 2019/04 -2021/03
• ハイパースペクトル撮影技術の開発

  五洋建設：

  Date (from‐to) : 2019/03 -2020/04
• Development of safe transportation system integrating vibration characteristics of art works, transport vehicles, packaging materials

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

  Date (from‐to) : 2016/04 -2020/03 

  Author : wada hiroshi

   

  In this study, vibrations were measured on a transportation system used for transportation of works of art, and vibration data were analyzed in all processes of each transportation of land, sea and air. Using the analysis results, the vibration environment during transportation was reproduced, and the measurement method and evaluation method of the response of the packaging material that received the vibration were established. Furthermore, we succeeded in grasping the phenomenon that accumulated fatigue occurs in the art material subject to vibration, and succeeded in verifying that even a small acceleration can cause deterioration of the art material gradually. Focusing on the vibration that occurs on the transportation system, we were able to verify the existence of the accumulated fatigue phenomenon, which is a risk of damage to cultural properties if they continue to be vibrated for a long time.
• Development of monitoring system for Bayon temple preservation and conservation

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

  Date (from‐to) : 2016/04 -2020/03 

  Author : Kawamura Youhei

   

  Historical monuments, archaeological sites and their surrounding structures found in World Heritage Sites (WHSs) all throughout the world have great cultural or physical significance. However, many of these WHSs are subject to decay and destruction from both natural and man-made events such as tourist activity. The study believes that it is possible to realize long-term and sustainable WHS monitoring by utilizing Information and Communication Technology (ICT). In this study, Bayon temple was selected as an application of the proposed monitoring system. The progressive deterioration of bas-reliefs found in the ruins require rapid and high-frequency monitoring; by utilizing fixed camera photography with multiple viewpoints, three-dimensional models holding color information are created and archived on a real-time basis measurement and communication system. Based on measured performance of the communications system, a schematic design of the monitoring system for WHSs has been developed.
• ３Dフォトグラメトリーによる発破ずりの粒度分布計測に関する研究

  石灰石鉱業協会：石灰石利用に関する基礎研究

  Date (from‐to) : 2019/04 -2020/03
• 振動解析による掘削補助装置の開発

  MMCリョウテック：

  Date (from‐to) : 2018/04 -2020/03
• Development of Seismic Damage Estimation System for Lifeline Networks Subjected to Multiple Effects of Extreme Ground Motions and Liquefaction

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)

  Date (from‐to) : 2016/04 -2020/03 

  Author : Shoji Gaku

   

  This study enhanced the accuracy of damage functions describing the nonlinear relationship between the seismic intensity and the quantified damage level, which are constituted in the following seismic damage estimation system, from the big-data analyses related with the seismic disasters for lifeline networks suffered by the multiple effects of extreme ground motions and liquefaction in the previous earthquakes. Based on these theorical approach, a new seismic damage estimation system of the lifeline networks was developed, which consists of four sub-systems: sub-system A of capturing spatial data on ground motion intensities, sub-system B of estimating lifelines damage distributed in a target region, sub-system C of sending associated disaster digital information and sub-system D of visualizing damage estimation data, with considering the maximization of the associated usability for local government officers and facility managers in the case of using the proposed system.
• アンコール遺跡群における砂岩浮き彫りの包括的な保存修復に関する研究

  日本学術振興会：科学研究費補助金 基盤研究(A)

  Date (from‐to) : 2013 -2016 

  Author : 松井敏也

   

  協力者
• 災害発生後の人的被害把握に関する研究

  日本学術振興会：日本‐インドネシア二国間交流事業

  Date (from‐to) : 2011 -2013 

  Author : 安信誠二

   

  分担者
• Fundamental Study on Non-destructive Testing Method for Foundation Pile using Giant-magnetostriction Vibrator

  Date (from‐to) : 2013 

  Author : 川村洋平
• Improving Student’s Strategic and Technical Skills through a Meaningful Interaction with Mining Industry

  Institute of Mining & Metallurgy：

  Date (from‐to) : 2013 

  Author : Erkan Topal
• ZigBeeを用いた地すべり監視ユビキタスセンシングネットワークの構築

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research

  Date (from‐to) : 2011 -2012 

  Author : 川村 洋平, 太田 敬一

   

  本研究では、無線通信の標準規格のひとつであるZigBeeを活用した斜面監視システムを提案している。ZigBeeを採用した理由は以下の2つの観点からである。 1)一つのネットワークに接続できる端末が多いことから対象斜面全体に柔軟にネットワーク構築ができる。 2)マルチホップ機能により、端末同士が相互にデータを転送し合うことにより、斜面の麓までデータ伝送することができる。 麓まで伝送されたデータは、公衆回線を利用して任意の計測室まで転送することができる。広域な地すべり斜面にZigBee設置する場合、接続形態としてデータ伝送を端末同士連携しながら行うことができるメッシュ型を用いる必要がある。メッシュ型を用いる場合、ZigBeeをZigBeeルータとして設定するがZigBeeルータは定期的に通信できることを確認するため端末は常に起動しており、待機電力が大きくなる。この電源消費量の問題に対する対策方法として本研究では、ZigBeeルータでありながらスリープが可能なGeoSenseを開発し斜面監視システムとして動作させた。また、315MHz特定小電力無線帯および413MHzアマチュア無線帯を起動信号として利用するトリガシステムを開発した。各ZigBeeにトランスミッタと、レシーバ組み込み、スイッチが入ったZigBeeは、周辺のZigBeeを起動させるために起動信号の電波を送る。周辺のZigBeeは、レシーバで起動信号を受信してZigBeeを起動させネットワークを自律的に構築できるようにした。 最終年は実際に地すべりが発生している地すべり警戒地域に本システムを設置し実規模計測を行った。計測期間に地すべりが発生しなかったことから、地すべりをトリガとした計測は実現できなかったが、人為的にトリガを超えさせることにより、すべてのZigBeeメードが起動し.ネットワークを構築できることを確認した。
• 百kHz帯超音波を用いたオイルサンドからのビチューメン 高効率抽出技術に関する基礎研究

  ＪＯＧＭＥＣ：出資金による受託研究

  Date (from‐to) : 2010/08 -2011/07 

  Author : 大川 浩一

   

  本研究課題はオイルサンドから超重質油・ビチューメンを熱水抽出する過程において超音波を補助的に使用し、高効率に回収することを目的とした基礎研究である。カナダのアルバータ州産および秋田県二ツ井町産オイルサンドを対象とし、超音波は、溶液中に均一および広範囲に微細気泡を生成することができる数百kHzを使用する。超音波を用いることで、どの程度まで低温で、かつ低薬品添加量で回収することができるか検討する。
• 小型地盤・月面掘削ロボット（DigBot）の開発」

  ＪＳＴ：出資金による受託研究

  Date (from‐to) : 2010/04 -2011/03 

  Author : 川村洋平

   

  JST A-STEP(フリージビリティスタディ)
• 地面掘削用小型ロボットにおける二重反転ドリルビットの開発

  (株)ユニバンス：国内共同研究

  Date (from‐to) : 2009/07 -2011/03 

  Author : 川村洋平
• Recovery of bitumen from Alberta oil sand using ultrasound irradiation

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

  Date (from‐to) : 2010 -2011 

  Author : OKAWA Hirokazu, KAWAMURA Youhei, KODA Shinobu, SASAKI Kyuro, SUGAI Yuichi

   

  Low (28 kHz) and high (200 kHz) frequency sonication combined with hot water treatments at 45 and 85℃ were investigated to assess the effects of different ultrasound frequencies and water temperatures on the recovery of bitumen from oil sand. A mechanical stirrer was also used to compare the efficiency of separation. Bitumen recovery tests were performed under argon, air, and nitrogen atmospheres. Sonication at 200 kHz was shown to recover bitumen effectively from oil sand at 85℃. For low temperature (45℃) solutions, only sonication at 28 kHz could recover bitumen from oil sand, demonstrating that sonication at 28 kHz can effectively breakdown the oil sand aggregates into a suspension. Hydrogen peroxide was also used to confirm the positive role for bitumen recovery. The role of highly concentrated H_2O_2 (>100 ppm) to recover bitumen during sonication was investigated. Hydrogen peroxide formed a bubble around the bitumen, which made it rise more easily to the solution surface during sonication. The result showed a good recovery rate of bitumen.
• 川村プロジェクト

  筑波大学学内プロジェクト奨励研究：筑波大学産学連携プロジェクト

  Date (from‐to) : 2011 

  Author : 川村洋平
• 国際連携プロジェクト海外長期派遣

  筑波大学：筑波大学国際連携プロジェクト

  Date (from‐to) : 2011 

  Author : 川村洋平
• 地面掘削用小型ロボットにおける組込み制御部の開発

  （株）北海道電子機器：国内共同研究

  Date (from‐to) : 2009/07 -2010/03 

  Author : 川村洋平
• ZigBeeによる土木ユビキタスネットワークの開発

  日本工営（株）：その他

  Date (from‐to) : 2008/09 -2010/03 

  Author : 川村洋平

   

  奨学寄附金
• 波の定規で世界を測る

  日本学術振興会：研究成果公開促進費

  Date (from‐to) : 2010 -2010 

  Author : 川村洋平
• PVT装置における粘度計測装置の開発に関する研究

  （財）石油天然ガス・金属鉱物資源機構：出資金による受託研究

  Date (from‐to) : 2008/08 -2009/03 

  Author : 川村洋平
• RPD研究開発における地耐力計測

  （株）丸順エンジニアリング、関東財務局：その他

  Date (from‐to) : 2007/12 -2008/03 

  Author : 川村洋平

   

  請負研究
• RPD研究開発における液状化計測

  （株）丸順エンジニアリング、関東財務局：その他

  Date (from‐to) : 2007/12 -2008/03 

  Author : 川村洋平

   

  請負研究
• Research on the New Method to Precipitate Green Tuff Suspension using Ultrasound Irradiation

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

  Date (from‐to) : 2007 -2008 

  Author : OKAWA Hirokaz, KAWAMURA Youhei, SATO Mineo, UEMATSU Kazuyoshi, SASAKI Kyuro, KODA Shinobu, YASUDA Keiji, SUGAWARA Katsuyasu

   

  比内緑色凝灰岩懸濁液を中心に、超音波の化学反応を利用した新規凝集方法を検討した。比内緑色凝灰岩懸濁液はpH7 でゼータ電位-40mV を有すが、pH4 で0mV となり沈殿することが明らかとなった。そこで高周波数域の超音波を懸濁液へ照射することにより得られるラジカルや硝酸に着眼し、ゼータ電位0mV であるpH 域まで照射することで、緑色凝灰岩懸濁液から懸濁粒子を沈殿回収することに成功した。本研究は高周波数の超音波照射により、水と空気から沈殿に必要な酸性化剤を生成するため、外部からの薬品添加を一切必要としなかった。超音波照射による酸性化は、溶存空気量に依存するため、溶液の温度が低いほどその効率は高いことが明らかになった。また、高周波数の照射では粒子の微細化は抑制されていた。緑色凝灰岩のみならず、他の懸濁液に対しても有効であった。
• A Constitutive Model and Numerical Simulation Method Applicable to Slow to Rapid Ground Flow Based on Micromechanics

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

  Date (from‐to) : 2006 -2008 

  Author : YAMADA Yasuo, MATSUSHIMA Takashi, KAWAMURA Yohei, IMAIZUMI Fumitoshi, KURAOKA Senro, KONAGAI Kazuo

   

  本研究では、液状化のような比較的低速度地盤流動から、土石流のような高速流動までを統一的に表現できる構成モデルの形式を、土粒子運動をベースに構成した。また、石礫型土石流の流体力に及ぼす粒子サイズの影響についても理論的検討を行った。更に、そのような地盤流動を、統一的に表現する解析手法としてSPH法を用い、その「粒子性」を利用して様々な地盤流動を比較的簡便に再現できることを示した。地盤流動実験や観測のための新手法の開発も行った。
• Stability assessment for rock slope using giant-magnetostriction vibrator

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

  Date (from‐to) : 2006 -2008 

  Author : KAWAMURA Youhei

   

  本研究では超磁歪振動子を入力に用いて岩盤斜面の安定性を評価すための手法を確立するために、コンクリートブロックの寸法推定実験及び実規模実験として凝灰岩の採石場にて凝灰岩の損傷検査を行った。解析手法として相互相関法、信号圧縮法、およびケプストラム解析を適用した。それぞれの解析の結果、ケプストラム解析が最も簡易な計測方法で良好な結果を得られることを確認した。また、その適用性を向上させるために、入力波形として連続した正弦波及び正弦波1波を適用し、入力波形に応じた改善策を提案した。
• 土粒子運動から構築する低速～高速地盤流動構成モデルの開発と応用

  日本学術振興会：科学研究費助成事業基盤研究（B)

  Date (from‐to) : 2006 -2008 

  Author : 山田恭央

   

  分担者
• 表面波探査によるロータピックドレン工法の検証

  その他

  Date (from‐to) : 2006/10 -2007/03 

  Author : 川村洋平

   

  奨学寄附金
• Development Research for Crop Growth Environment Sensing Grid in Large-scale Spaces

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

  Date (from‐to) : 2005 -2007 

  Author : MIZUTANI Koichi, WAKATSUKI Naoto, KAWAMURA Youhei, SASE Sadanori, OKUSHIMA Rimi, ISHII Masahisa

   

  In the large-scale agricultural management, to improve the efficiency of productivity, it is necessary for farming industry to monitoring air temperature, fog, geologic condition, and condition, and soil property, etc. Our research intended to project a new observation system called "sensing grid" for the large-scale space to monitor the parameters for crop growth environment. We focused our attention on the sound velocity that has relationship between these parameters, and assembled theories between the velocity and the parameters. Based on these theories, we proposed a sound probe system that enables to precisely measure space mean values of air temperature and wind velocity by measuring time-of-flight of sound. As experimental results, we appraised relationship between parameters and sound velocity by using the sound probe. To enable monitoring environment in large-space by the sound probe more easily, we expanded this system and proposed a network acoustic sensing system. In this system, the probes transmit and wirelessly receive a measured data each other. We realized the monitoring various parameters in more long and wide area with simple and effective technique. The experimental results suggest that the parameters for the crop growth environment can be obtained by the network sensor system. Two dimensional distributions of wind direction and wind velocity and temperature were measured by the sound probes and reconstructed by the CT method. We also proposed network sensing grid monitoring system to enable monitoring system to enable monitoring environment in large-space. By using this system, we can methodically obtain various parameters. This system consists of acoustic sensors that are dispersed in grid pattern. We can get parameters from controller that consolidates each parameter from arbitrary combination of sensors. Moreover. Unit-cell method allows this system more greater flexibility. We get temperature distribution by matrix method with one unit-cell. These obtained results suggest that our system can make a contribution for not only large-scale bioplant by offering environment-control and improving the efficiency of crop productivity but also protected horticulture engineering, or whole industry.
• ローテータ方式杭工法に関する研究

  （株）丸順重工：その他

  Date (from‐to) : 2005/10 -2006/03 

  Author : 川村洋平
• ローテータ方式砕石杭工法に関する研究

  丸順重工（株）：企業からの受託研究

  Date (from‐to) : 2005/10 -2006/03 

  Author : 金久保利之
• セラミック圧電素子を用いた超音波直接加振による転石根入れ深さ探査

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

  Date (from‐to) : 2004 -2005 

  Author : 川村 洋平

   

  近年、自然災害による被害が多発している。その多くは落石による被害である。転石は岩石の一部が地表面に露出している以外は地中に埋っているため、その体積・根入れ深さの調査は容易ではない。この転石が多量の雨や地震等により落石となる。本研究は露岩部からの調査により、転石の根入れ深さを推定することを目的としている。転石根入れ深さを推定可能となれば、その転石の安定度が判別できる。従来法としては弾性波の入力部にハンマーを用いている。この手法は大きな入力を発生させることができる反面、精度および再現性に問題があった。一方、精密機械や構造物に対し、非破壊検査で用いられる手法としては超音波法が挙げられる。こちらは精度が高い反面、探査深度が浅くなるという問題があった。 本研究ではこれらの問題点を解決すべく、高精度で探査深度の深い転石根入れ深さ探査システムの構築を行った。入力部には圧電セラミックス、受信部には高感度AEセンサを採用することにより、大出力、高精度を実現することが可能となった。 基礎実験には長軸900mmのコンクリートブロックと1400mmの白御影石を使用、実規模実験においては地中に埋められている長軸1360mmの街頭基礎を供試体として用いた。解析手法としてはチャープ波を使った自己相関分析および正弦波・チャープ波を使ったケプストラム解析を行った。その結果、実規模においても誤差5%以内で良好な根入れ深さ推定を行うことに成功した。自己相関分析においては条件に合った入力波を作成することが出来れば誤差1%以内の非常に良好な結果が得られるが、その条件を満たすのが困難である。ケプストラム解析においては入力振幅を大きくすることにより、ある程度の結果が見込める。これらを統合することによりシステムの完成度が飛躍的に向上する結果となった。
• セラミック圧電素子を用いた超音波直接加振による転石根入れ深さ探査

  日本学術振興会：若手研究(B)

  Date (from‐to) : 2005 

  Author : 川村洋平
• Development of management system of Construction machinery using mobile multimedia network.

Industrial Property Rights

• 特願2020-149395:鉱石の判別方法及び、鉱石の選別方法  2020年

  川村洋平, 柴山敦, 芳賀一寿  JX金属、秋田大学
• 特願2019-074309:風向風速計測方法及び風向風速計測システム  2019年/12/01

  川村洋平, 伊達央  秋田大学
• 特願2017-083872:対象物推定装置  2017年

  川村洋平, 安達毅, 伊藤豊  秋田大学、安藤・間
• 特願2016-008446:三次元被写体形状推定装置  2016年

  川村洋平, 北原格, Jang Hyongdoo  筑波大学
• 特願2010-200351:地中移動体位置推定システム  2010年/09/07

  川村洋平, 田村潤平  筑波大学  

  地中移動体の位置を弾性波によって計測する
• 特願2010-200096:ドリルヘッド位置推定システム  2010年/09/07

  川村洋平, 田村潤平, 持地英実, 佐々木直人  筑波大学、（株）多田建設  

  ＨＤＤ工法におけるドリルビット先端位置を弾性波によって計測する
• 2009-189417号:掘削装置  2009年/10

  川村洋平, 土方大輔  筑波大学、ユニバンス、北海道電子機器
• 特願2009-154197号:掘削装置  2009年/06

  川村洋平, 阿部亮平  筑波大学、北海道電子機器
• 特願2009-063326号:掘削装置およびドリルビットユニット  2009年/03/20

  川村洋平, 阿部亮平, 飯高  筑波大学
• 特願2008-051222号:2次元画像データ生成方法および探査装置  2008年/11/01

  河宜成, 川村洋平  筑波大学
• 特願2004-260634号:埋没物体の非破壊形状診断およびその装置  2004年/09/01

  川村洋平  （株）日本工営
• 特願2000-28000号:不燃気筒検出装置  2000年

  川村, 洋平  氏平増之

Social Contribution

• 三菱商事株式会社研修（資源講座）

  Date (from-to) : 2023/11/15

  Role : Lecturer

  Sponser, Organizer, Publisher  : 三菱商事株式会社
• サイエンスレクチャー2023

  Date (from-to) : 2023/10/14

  Role : Lecturer

  Sponser, Organizer, Publisher  : 読売新聞北海道支社
• サイエンス・カフェ札幌

  Date (from-to) : 2023/09/10

  Role : Appearance

  Sponser, Organizer, Publisher  : 北海道大学 大学院教育推進機構 オープンエデュケーションセンター、科学技術コミュニケーション教育研究部門（CoSTEP）
• 旭川工業高等専門学校出前授業

  Date (from-to) : 2023/09/06

  Role : Lecturer

  Sponser, Organizer, Publisher  : 旭川工業高等専門学校
• 住友商事株式会社研修（採鉱学・発破）

  Date (from-to) : 2023/07/11

  Role : Lecturer

  Sponser, Organizer, Publisher  : 住友商事株式会社
• 北大道新アカデミー

  Date (from-to) : 2023/05/20

  Role : Lecturer

  Sponser, Organizer, Publisher  : 株式会社道新文化センター
• 双日株式会社研修（鉱山開発技術のDX）

  Date (from-to) : 2023/02/27

  Role : Lecturer

  Sponser, Organizer, Publisher  : 双日株式会社
• 三菱商事株式会社研修（鉱山工学）

  Date (from-to) : 2020/11

  Role : Lecturer

  Sponser, Organizer, Publisher  : 三菱商事株式会社
• 帯広柏葉高校出前講義（スマートマイニング）

  Date (from-to) : 2020/06

  Role : Lecturer

  Sponser, Organizer, Publisher  : 帯広柏葉高校
• 住友商事株式会社研修（鉱山工学）

  Date (from-to) : 2019/11

  Role : Lecturer

  Sponser, Organizer, Publisher  : 住友商事株式会社
• 防災テクノロジーの進化

  Date (from-to) : 2019/08-2019/09

  Role : Lecturer

  Sponser, Organizer, Publisher  : 秋田大学

  Event, Program, Title : 秋田大学国際資源学部公開講座
• 秋田大学国際資源学部公開講座

  Date (from-to) : 2019

  Role : Lecturer

  Sponser, Organizer, Publisher  : 秋田大学
• 院内銀山を利活用した地域発展

  Date (from-to) : 2017/10

  Role : Advisor

  Sponser, Organizer, Publisher  : 湯沢市
• 学際的資源開発研究会（会長）

  Date (from-to) : 2017

  Role : Planner

  Sponser, Organizer, Publisher  : 川村洋平

Media Coverage

• Clean power initiative boosts energy access in Tajikistan

  Date : 2023/12

  Writer: Other than myself

  Publisher, broadcasting station: Nature Portfolio

  Program, newspaper magazine: Nature Portfolio

  Paper
• 製鉄でもCO2減豪中連携（分析）

  Date : 2019/11

  Writer: Other than myself

  Program, newspaper magazine: 日本経済新聞

  コメント Paper
• 5年で大化け！サイエンス＆ベンチャー105発

  Date : 2019/10

  Writer: Other than myself

  Program, newspaper magazine: 週刊 ダイヤモンド

  月面開発 Paper
• 秋田大アフリカ資源シンポ開く

  Date : 2018/12

  Writer: Other than myself

  Program, newspaper magazine: 日刊産業新聞

  Paper
• どうする地域活性化

  Date : 2018/12

  Program, newspaper magazine: 秋田さきがけ新報

  Paper
• バーチャルで見る 院内銀山と院内の町並み

  Date : 2018/04

  Writer: Other than myself

  Publisher, broadcasting station: ABSラジオ

  Program, newspaper magazine: Radipal

  Media report
• 鉱山VR

  Date : 2017/12

  Publisher, broadcasting station: AKT秋田テレビ

  Program, newspaper magazine: プライムニュース秋田

  Media report

Others

• 2012 -2012 Regional council in Queensland, Advisor, Queensland