研究者データベース

川村 洋平(カワムラ ヨウヘイ)
工学研究院 環境循環システム部門 資源循環工学分野
教授

基本情報

所属

  • 工学研究院 環境循環システム部門 資源循環工学分野

職名

  • 教授

学位

  • 博士(工学)(北海道大学)
  • 修士(工学)(北海道大学)

連絡先

  • kawamuraeng.hokudai.ac.jp

J-Global ID

研究キーワード

  • 鉱山工学   資源情報学   災害情報学   

研究分野

  • エネルギー / 地球資源工学、エネルギー学
  • 社会基盤(土木・建築・防災) / 地盤工学
  • 社会基盤(土木・建築・防災) / 防災工学
  • ものづくり技術(機械・電気電子・化学工学) / 計測工学
  • 自然科学一般 / 固体地球科学
  • 人文・社会 / 地域研究

職歴

  • 2021年06月 - 現在 北海道大学 大学院工学研究院 教授
  • 2019年12月 - 現在 華北科技学院 栄誉教授
  • 2016年01月 - 2021年05月 秋田大学 大学院国際資源学研究科 教授
  • 2017年04月 - 2019年03月 秋田大学 国際資源学教育研究センター センター長
  • 2015年04月 筑波大学 システム情報系 准教授
  • 2014年12月 - 2015年03月 Curtin University Dept. of Mining Engineering Senior Lecturer
  • 2012年05月 - 2014年11月 Curtin University Dept. of Mining Engineering Lecturer
  • 2004年04月 - 2012年04月 筑波大学 大学院システム情報工学研究科 講師
  • 2003年04月 - 2004年03月 筑波大学 機能工学系 講師

学歴

  •         - 2003年   北海道大学大学院   工学研究科   環境資源工学
  •         - 2000年03月   北海道大学大学院   工学研究科   環境資源工学

所属学協会

  • 物理探査学会   日本音響学会   土木学会   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   資源・素材学会   計測自動制御学会   MPES   Mining Education Australia   AusIMM   

研究活動情報

論文

  • Hisatoshi Toriya, Ashraf Dewan, Hajime Ikeda, Narihiro Owada, Mahdi Saadat, Fumiaki Inagaki, Youhei Kawamura, Itaru Kitahara
    Applied Sciences (Switzerland) 12 9 2022年05月01日 
    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.
  • 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 2022年 
    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.
  • Zedrick Paul L. Tungol, Hisatoshi Toriya, Narihiro Owada, Itaru Kitahara, Fumiaki Inagaki, Mahdi Saadat, Hyong Doo Jang, Youhei Kawamura
    MINERALS 11 12 2021年12月 
    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.
  • Brian Bino Sinaice, Narihiro Owada, Mahdi Saadat, Hisatoshi Toriya, Fumiaki Inagaki, Zibisani Bagai, Youhei Kawamura
    MINERALS 11 8 2021年08月 
    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.
  • Fumiya Kimura, Yutaka Ito, Toshiya Matsui, Hidehiko Shishido, Itaru Kitahara, Youhei Kawamura, Atsuyuki Morishima
    JOURNAL OF CULTURAL HERITAGE 50 163 - 170 2021年07月 
    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.
  • Mahdi Saadat, Abbas Taheri, Youhei Kawamura
    COMPUTERS AND GEOTECHNICS 135 104144 - 104144 2021年07月 [査読有り][通常論文]
     
    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.
  • Mahdi Saadat, Abbas Taheri, Youhei Kawamura
    ENGINEERING FRACTURE MECHANICS 248 107744 - 107744 2021年05月 [査読有り][通常論文]
     
    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.
  • Elsa Pansilvania Andre Manjate, Mahdi Saadat, Hisatoshi Toriya, Fumiaki Inagaki, Youhei Kawamura
    Journal of Sustainable Mining 20 4 296 - 308 2021年 
    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.
  • Hisatoshi Toriya, Narihiro Owada, Mahdi Saadat, Fumiaki Inagaki, Ashraf Dewan, Youhei Kawamura, Itaru Kitahara
    Array 12 100102 - 100102 2021年
  • Taeyoo Na, Youhei Kawamura, Seong-seung Kang, Shinji Utsuki
    GEOMATICS NATURAL HAZARDS & RISK 12 1 347 - 362 2021年01月01日 [査読有り][通常論文]
     
    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.
  • Natsuo Okada, Yohei Maekawa, Narihiro Owada, Kazutoshi Haga, Atsushi Shibayama, Youhei Kawamura
    MINERALS 10 9 1 - 22 2020年09月 
    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%.
  • Hirokazu Okawa, Tomonao Saito, Shohei Yasuda, Youhei Kawamura, Takahiro Kato, Katsuyasu Sugawara, Tayfun Babadagli
    JAPANESE JOURNAL OF APPLIED PHYSICS 59 SK 2020年07月01日 [査読有り][通常論文]
     
    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
  • Hidehiko Shishido, Emi Kawasaki, Youhei Kawamura, Toshiya Matsui, Itaru Kitahara
    ACM JOURNAL ON COMPUTING AND CULTURAL HERITAGE 13 2 10 - 18 2020年06月 
    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.
  • 伊藤 豊, 竹内 誠人, 見上 柊人, 川村 洋平
    Journal of MMIJ 136 5 33 - 39 2020年05月31日 [査読有り][通常論文]
  • 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 2020年04月 [査読有り][通常論文]
     
    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.
  • Yutaka Ito, Shuto Mikami, Hyongdoo Jang, Abbas Taheri, Kenta Tanaka, Youhei Kawamura
    RESOURCES-BASEL 9 3 2020年03月01日 
    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.
  • Brian Bino Sinaice, Youhei Kawamura, Jaewon Kim, Natsuo Okada, Itaru Kitahara, Hyongdoo Jang
    Springer Series in Geomechanics and Geoengineering 228 - 235 2020年 
    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.
  • Hajime Ikeda, Youhei Kawamura, Hyongdoo Jang, Nur Ellisha Binti Mokhtar, Jun Yokokura, Zedrick Paul L. Tungol
    Springer Series in Geomechanics and Geoengineering 236 - 244 2020年 
    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.
  • Mohammad Ali Moridi, Mostafa Sharifzadeh, Hyongdoo Jang, Youhei Kawamura
    Springer Series in Geomechanics and Geoengineering 255 - 261 2020年 
    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.
  • Hyongdoo Jang, Sina Taheri, Erkan Topal, Youhei Kawamura
    Springer Series in Geomechanics and Geoengineering 457 - 466 2020年 
    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.
  • 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年10月 
    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.
  • Hyongdoo Jang, Youhei Kawamura, Utsuki Shinji
    TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 92 2019年10月 [査読有り][通常論文]
     
    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.
  • アンコール遺跡群における地衣類の時系列変化画像の重畳
    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 730 29 - 33 ニューサイエンス社 2019年09月 [査読無し][通常論文]
  • ICを活用した予防保全のためのアンコール遺跡群バイヨン寺院を対象としたモニタリングシステムの開発
    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
    日本文化財科学会第36回大会発表要旨集 20 - 21 日本文化財科学会第36回事務局 2019年06月 [査読無し][通常論文]
  • H. Ikeda, Y. Kawamura, Z. P.L. Tungol, M. A. Moridi, H. Jang
    Journal of Mining Science 55 3 505 - 514 2019年05月01日 
    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.
  • Mohammad Ali Moridi, Mostafa Sharifzadeh, Youhei Kawamura, Hyong Doo Jang
    TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 73 127 - 138 2018年03月 [査読有り][通常論文]
     
    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.
  • Mohammad Ali Moridi, Youhei Kawamura, Mostafa Sharifzadeh, Emmanuel Knox Chanda, Markus Wagner, Hirokazu Okawa
    TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 71 201 - 209 2018年01月 [査読有り][通常論文]
     
    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.
  • Hidehiko Shishido, Emi Kawasaki, Yutaka Ito, Youhei Kawamura, Toshiya Matsui, Itaru Kitahara
    2018 IEEE INTERNATIONAL CONFERENCE ON BIG DATA (BIG DATA) 3541 - 3542 2018年 [査読有り][通常論文]
     
    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年08月 [査読有り][通常論文]
  • Hirokazu Okawa, Kentaro Nishi, Youhei Kawamura, Takahiro Kato, Katsuyasu Sugawara
    JAPANESE JOURNAL OF APPLIED PHYSICS 56 7 2017年07月 [査読有り][通常論文]
     
    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.
  • 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 2017年07月01日 [査読有り][通常論文]
     
    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 116 496 197 - 202 電子情報通信学会 2017年02月 [査読無し][通常論文]
  • Jang Hyongdoo, Topal Erkan, Kawamura Youhei
    INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY 26 6 1095 - 1100 2016年11月01日 [査読有り][通常論文]
     
    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.
  • Y. Kawamura, H. Jang, K. Ohta, Y. Inagaki
    Geotechnical Special Publication 2016-January 269 GSP 542 - 550 2016年 [査読有り][通常論文]
     
    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.
  • Itaru Kitahra, Shogo Atsumi, Ryo Degawa, Youhei Kawamura, Hyongdoo Jang, Yuichi Ohta
    Geotechnical Special Publication 2016- 269 508 - 517 2016年 [査読有り][通常論文]
     
    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.
  • Rui Wang, Youhei Kawamura
    JOURNAL OF SENSORS 2016 8121678 - 15 2016年 [査読有り][通常論文]
     
    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.
  • Rui Wang, Youhei Kawamura
    INDUSTRIAL ROBOT-THE INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH AND APPLICATION 43 4 429 - 447 2016年 [査読有り][通常論文]
     
    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.
  • 浮き彫り保存のための強化剤で処理した砂岩のアコースティックエミッション
    跡見,洋祐, 松井,敏也, 川村 洋平
    アンコール遺跡調査報告書2014-2015 161 - 162 日本国政府アンコール遺跡救済チーム 2015年12月 [査読無し][通常論文]
  • 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 2015年12月 [査読有り][通常論文]
     
    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.
  • 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 2015年09月01日 [査読有り][通常論文]
     
    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.
  • Youhei Kawamura, Hyongdoo Jang, Markus Wagner, Hajime Nobuhara, Ashraf M. Dewan, Bert Veenendaal, Itaru Kitahara
    JOURNAL OF DISASTER RESEARCH 10 4 655 - 666 2015年08月01日 [査読有り][通常論文]
     
    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.
  • 観光客に起因する振動の調査(第2報)-旧富岡製糸場 東置繭書における事例―
    跡見,洋祐, 松井,敏也, 川村,洋平
    日本文化財科学第32回大会研究発表要旨集 96 - 97 日本文化財科学会 2015年07月 [査読無し][通常論文]
  • Hirokazu Okawa, Tomohiro Yoshikawa, Ryota Hosokawa, Shinji Hangui, Youhei Kawamura, Katsuyasu Sugawara
    JAPANESE JOURNAL OF APPLIED PHYSICS 54 7 2015年07月01日 [査読有り][通常論文]
     
    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.
  • Hyongdoo Jang, Erkan Topal, Youhei Kawamura
    APPLIED SOFT COMPUTING 32 1 - 12 2015年07月01日 [査読有り][通常論文]
     
    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.
  • H. Jang, E. Topal, Y. Kawamura
    JOURNAL OF THE SOUTHERN AFRICAN INSTITUTE OF MINING AND METALLURGY 115 5 449 - 456 2015年05月 [査読有り][通常論文]
     
    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.
  • H. Jang, E. Topal, Y. Kawamura
    Journal of the Southern African Institute of Mining and Metallurgy 115 5 449 - 456 2015年 [査読有り][通常論文]
     
    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.
  • 振動解析による石造遺跡の予防診断法の開発Ⅱ-凍結融解による破壊分析-
    跡見,洋祐, 松井,敏也, 川村,洋平
    日本文化財科学会第31回大会研究発表要旨集 86 - 87 日本文化財化学会 2014年07月 [査読無し][通常論文]
  • Mohammad Ali Moridi, Youhei Kawamura, Mostafa Sharifzadeh, Emmanuel Knox Chanda, Hyongdoo Jang
    TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 43 362 - 369 2014年07月 [査読有り][通常論文]
     
    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.
  • 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 2014年04月 [査読有り][通常論文]
     
    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.
  • 川岸,卓司, 善甫,啓一, 水谷,孝一, 若槻,尚斗, 川村,洋平
    土木学会論文集F3(土木情報学) 69 2 I_130 - I_138 Japan Society of Civil Engineers 2014年03月 [査読有り][通常論文]
     
    本稿は土中で発生する音源の位置測定法に関するものである.提案手法では,直達音だけではなく,地表面からの反射音も利用することで測定精度の向上を図っている.地表面で起こる反射音を利用するために,鉛直方向に一対の素子を配置した杭状のジオフォンを用いている.杭状ジオフォンアレイを2本(素子数:4)用いた評価実験の結果,位置推定精度は直達音のみを使用する従来手法と比べ3.42倍と向上することがわかった.また,ジオフォンアレイの配置や構成する素子のずれが音源位置の推定に与える影響を実規模シミュレーションにより実験し,提案手法の位置推定精度は従来手法に比べ最大で14.6倍に向上できることを確認した.以上より,従来手法に比べ高精度の音源位置測定が可能であることが示された.
  • Y. Kawamura, M. A. Moridi, M. Sharifzadeh, H. Jang
    ISRM International Symposium - 8th Asian Rock Mechanics Symposium, ARMS 2014 1411 - 1420 2014年 
    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.
  • Ashraf M. Dewan, Kamrun Nahar, Yohei Kawamura
    Dhaka Megacity: Geospatial Perspectives on Urbanisation, Environment and Health 239 - 256 2014年01月01日 
    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.
  • Rui Wang, Youhei Kawamura
    2014 11TH WORLD CONGRESS ON INTELLIGENT CONTROL AND AUTOMATION (WCICA) 2015-March March 3303 - 3308 2014年 [査読有り][通常論文]
     
    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.
  • 少数ハイドロフォンアレイを用いる船舶スクリュー軸振れ検出(ポスターセッション)
    川岸,卓司, 善甫,啓一, 水谷,孝一, 若槻,尚斗, 海老原,格, 川村,洋平
    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講演論文集 34 357 - 358 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 2013年11月 [査読無し][通常論文]
  • 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年09月 [査読無し][通常論文]
  • 大川 浩一, 斉藤 知直, 菅原 勝康, 川村 洋平, Babadagli Tayfun
    ソノケミストリー討論会講演論文集 22 11 - 12 日本ソノケミストリー学会 2013年 
    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.
  • Satoki Ogiso, Koichi Mizutani, Naoto Wakatsuki, Youhei Kawamura
    2013 IEEE 2nd Global Conference on Consumer Electronics, GCCE 2013 74 - 77 2013年 [査読有り][通常論文]
     
    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.
  • Shingo Kamagata, Youhei Kawamura, Hirokazu Okawa, Koichi Mizutani
    JAPANESE JOURNAL OF APPLIED PHYSICS 51 7 07GE03  2012年07月 [査読有り][通常論文]
     
    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.
  • Hirokazu Okawa, Kentaro Nishi, Dai Shindo, Youhei Kawamura
    JAPANESE JOURNAL OF APPLIED PHYSICS 51 7 07GE06  2012年07月 [査読有り][通常論文]
     
    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.
  • 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年 
    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.
  • Masahiro Hayashi, Toshiyuki Miyachi, Youhei Kawamura, Kazutoshi Murakami, Yuichi Kato, Hiroshi Mochiyama
    ISCIIA 2012 - 5th International Symposium on Computational Intelligence and Industrial Applications 2012年 
    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.
  • Seiji Yasunobu, Hajime Nobuhara, Yohei Kawamura
    ISCIIA 2012 - 5th International Symposium on Computational Intelligence and Industrial Applications 2012年 
    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 超音波霧化を利用した湿度調整とその防塵特性(ポスターセッション)
    大川, 浩一, 西, 健太郎, 進藤, 大, 川村, 洋平
    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講演論文集 0 32 133 - 134 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 2011年11月 [査読無し][通常論文]
  • Junpei Tamura, Youhei Kawamura, Hidemi Mochiji, Naoto Sasaki, Koichi Mizutani, Hirokazu Okawa
    Japanese Journal of Applied Physics 50 07HC15-1 - 07HC12-6 2011年07月 [査読有り][通常論文]
  • Junpei Tamura, Youhei Kawamura, Hidemi Mochiji, Naoto Sasaki, Koichi Mizutani, Hirokazu Okawa
    JAPANESE JOURNAL OF APPLIED PHYSICS 50 7 2011年07月 [査読有り][通常論文]
     
    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.
  • Hirokazu Okawa, Tomonao Saito, Ryota Hosokawa, Takashi Nakamura, Youhei Kawamura, Shinobu Koda
    JAPANESE JOURNAL OF APPLIED PHYSICS 50 7 2011年07月 [査読有り][通常論文]
     
    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
  • Takashi Nakamura, Hirokazu Okawa, Youhei Kawamura, Katsuyasu Sugawara
    Japanese Journal of Applied Physics 50 7 PART 2 2011年07月 [査読有り][通常論文]
     
    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 + +
  • Takashi Nakamura, Hirokazu Okawa, Youhei Kawamura, Katsuyasu Sugawara
    JAPANESE JOURNAL OF APPLIED PHYSICS 50 7 07HE16 - 07HE16-4 2011年07月 [査読有り][通常論文]
     
    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
  • 蒲原, 章裕, 川村, 洋平, 鎌形, 真伍, 大川, 浩一
    Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan 127 4 182 - 188 社団法人 資源・素材学会 2011年03月 [査読有り][通常論文]
     
    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.
  • 安藤 寛, 佐々木 久郎, 川村 洋平, 大川 浩一, 菅井 裕一
    石油学会 年会・秋季大会講演要旨集 2011 103 - 103 公益社団法人 石油学会 2011年 
    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。
  • Takashi Nakamura, Hirokazu Okawa, Youhei Kawamura, Katsuyasu Sugawara
    ULTRASONICS SONOCHEMISTRY 18 1 85 - 91 2011年01月 [査読有り][通常論文]
     
    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.
  • 田村 潤平, 川村 洋平, 持地 英実, 佐々木 直人, 大川 浩一, 水谷 孝一
    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講演論文集 32 32 477 - 478 特定非営利活動法人 超音波エレクトロニクス協会 2011年 [査読無し][通常論文]
  • 鎌形 真伍, 川村 洋平, 大川 浩一, 水谷 孝一
    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講演論文集 32 32 371 - 372 特定非営利活動法人 超音波エレクトロニクス協会 2011年 [査読無し][通常論文]
  • 2P-42 超音波照射を用いたオイルサンドからのビチューメンの低温抽出(ポスターセッション)
    大川, 浩一, 細川, 亮太, 斉藤, 知直, 中村, 貴司, 川村, 洋平
    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講演論文集 0 31 373 - 374 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 2010年12月 [査読有り][通常論文]
  • 2P-35 超音波補助によるシュウ酸を用いた緑色凝灰岩からの鉄抽出効率の改善(ポスターセッション)
    中村, 貴司, 大川, 浩一, 川村, 洋平, 菅原, 勝康
    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講演論文集 0 31 359 - 360 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 2010年12月 [査読有り][通常論文]
  • T.Nakamura, H.Okawa, R.Hosokawa, T.Saito, Y.Kawamura, and, K.Sugawara, 川村, 洋平
    Jpn. J. of Appl. Phys. 49 07HE11  応用物理学会 2010年08月 [査読有り][通常論文]
  • Takashi Nakamura, Hirokazu Okawa, Ryouta Hosokawa, Tomonao Saito, Youhei Kawamura, Katsuyasu Sugawara
    JAPANESE JOURNAL OF APPLIED PHYSICS 49 7 0 - 0 2010年07月 [査読有り][通常論文]
     
    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
  • Hirokazu Okawa, Tomonao Saito, Ryota Hosokawa, Takashi Nakamura, Youhei Kawamura, Katsuyasu Sugawara
    JAPANESE JOURNAL OF APPLIED PHYSICS 49 7 0 - 0 2010年07月 [査読有り][通常論文]
     
    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.
  • Nakamura, Takashi, Okawa, Hirokazu, Hosokawa, Ryouta, Saito, Tomonao, Kawamura, Youhei, Sugawara, Katsuyasu
    Jpn J Appl Phys 49 7 07HE11 - 07HE11-4 Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics 2010年07月 [査読有り][通常論文]
     
    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.
  • Hirokazu Okawa, Tomonao Saito, Ryota Hosokawa, Takashi Nakamura, Youhei Kawamura, Katsuyasu Sugawara
    Japanese Journal of Applied Physics 49 7 07HE12  2010年07月 [査読有り][通常論文]
     
    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 磁気車輪を用いた鉄橋非破壊検査装置のための移動機構の開発(一般講演 ロボット)
    土方, 大輔, 川村, 洋平, 宇都木, 隆裕
    日本機械学会関東支部総会講演会講演論文集 2010 16 231 - 232 一般社団法人日本機械学会 2010年03月 [査読無し][通常論文]
     
    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.
  • 大川 浩一, 中村 貴司, 川村 洋平, 菅原 勝康
    ソノケミストリー討論会講演論文集 19 45 - 46 日本ソノケミストリー学会 2010年 
    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.
  • 川村 洋平, 田村 潤平, 持地 英実, 水谷 孝一, 大川 浩一
    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講演論文集 31 31 39 - 40 特定非営利活動法人 超音波エレクトロニクス協会 2010年 [査読有り][通常論文]
  • Ryouhei Abe, Youhei Kawamura, Kazushi Kamijima, Kazutosi Murakami
    Proceedings of the SICE Annual Conference 885 - 888 2010年 [査読有り][通常論文]
     
    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.
  • Yuya Nakahata, Youhei Kawamura
    Proceedings of the SICE Annual Conference 1191 - 1194 2010年 [査読有り][通常論文]
     
    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年12月 [査読有り][通常論文]
  • 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年12月 [査読有り][通常論文]
  • 2P4-17 超音波照射を用いた微生物汚染土壌の浄化処理(ポスターセッション)
    中村, 貴司, 大川, 浩一, 川村, 洋平, 菅原, 勝康
    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講演予稿集 0 30 317 - 318 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 2009年11月 [査読有り][通常論文]
  • 1P4-33 超音波照射を用いたオイルサンドからのビチューメン抽出に関する研究(ポスターセッション)
    大川, 浩一, 細川, 亮太, 斉藤, 知直, 中村, 貴司, 川村, 洋平
    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講演予稿集 0 30 151 - 152 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 2009年11月 [査読有り][通常論文]
  • 中村, 貴司, 大川, 浩一, 川村, 洋平, 高畑, 重幸, 中, 秀男, 菅原, 勝康
    環境資源工学 : 資源処理技術 / 環境資源工学会 [編] 56 1 13 - 20 環境資源工学会 2009年04月 [査読有り][通常論文]
     
    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
  • 中村 貴司, 大川 浩一, 川村 洋平, 菅原 勝康
    ソノケミストリー討論会講演論文集 18 69 - 70 日本ソノケミストリー学会 2009年 
    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.
  • 蒲原 章裕, 川村 洋平, 中畑 裕也, 大川 浩一, 水谷 孝一
    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講演論文集 30 30 83 - 84 特定非営利活動法人 超音波エレクトロニクス協会 2009年 [査読有り][通常論文]
  • 川村 洋平, 河 宜成, 蒲原 章裕, 大川 浩一
    Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan 124 12 801 - 807 資源・素材学会 2008年12月25日 [査読有り][通常論文]
     
    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年10月 [査読有り][通常論文]
  • 川村 洋平, 浅香 充慶, 河 宜成, 大川 浩一, 水谷 孝一
    Journal of MMIJ : journal of the Mining and Materials Processing Institute of Japan 124 6 452 - 458 一般社団法人 資源・素材学会 2008年07月25日 [査読有り][通常論文]
     
    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.
  • Euiseong Ha, Youhei Kawamura, Koichi Mizutani, Akihiro Kamohara, Hirokazu Okawa
    JAPANESE JOURNAL OF APPLIED PHYSICS 47 5 3946 - 3951 2008年05月23日 [査読有り][通常論文]
     
    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.
  • Hirokazu Okawa, Junpei Yabuki, Youhei Kawamura, Ichiro Arise, Mineo Sato
    MATERIALS RESEARCH BULLETIN 43 5 1203 - 1208 2008年05月06日 [査読有り][通常論文]
     
    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 +
  • Ha, Euiseong, Kawamura, Youhei, Mizutani, Koichi, Kamohara, Akihiro, Okawa, Hirokazu
    JAPANESE JOURNAL OF APPLIED PHYSICS 47 5:Part 2 3946 - 3951 JAPAN SOCIETY APPLIED PHYSICS 2008年05月 [査読有り][通常論文]
  • 中村 貴司, 大川 浩一, 川村 洋平, 菅原 勝康
    ソノケミストリー討論会講演論文集 17 36 - 37 日本ソノケミストリー学会 2008年 
    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.
  • 工藤 陽太, 大川 浩一, 川村 洋平, 菅原 勝康, 佐藤 峰夫
    ソノケミストリー討論会講演論文集 17 54 - 55 日本ソノケミストリー学会 2008年 
    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.
  • 川村 洋平
    計測と制御 = Journal of the Society of Instrument and Control Engineers 46 10 815 - 816 2007年10月10日 [査読有り][通常論文]
  • 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年09月 [査読有り][通常論文]
  • 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 2007年07月26日 [査読有り][通常論文]
     
    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.
  • 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 2007年07月26日 [査読有り][通常論文]
     
    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.
  • Y. Kawamura, M. Nagayama, M. Ujihira
    International Journal of Mining, Reclamation and Environment 21 2 97 - 110 2007年06月 [査読有り][通常論文]
     
    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.
  • 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 2007年03月29日 [査読無し][通常論文]
  • 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 2007年03月29日 [査読無し][通常論文]
  • 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 2007年03月29日 [査読無し][通常論文]
  • 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 2007年03月29日 [査読無し][通常論文]
  • 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 2007年03月29日 [査読無し][通常論文]
  • 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 2007年03月 [査読無し][通常論文]
  • 大川 浩一, 中村 貴司, 中里 慎吾, 川村 洋平, 佐藤 峰夫
    ソノケミストリー討論会講演論文集 16 1 - 2 日本ソノケミストリー学会 2007年 
    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.
  • 蒲原 章裕, 川村 洋平, 河 宜成, 大川 浩一, 水谷 孝一
    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講演論文集 28 28 389 - 390 特定非営利活動法人 超音波エレクトロニクス協会 2007年 [査読無し][通常論文]
  • 河 宜成, 川村 洋平, 大川 浩一, 水谷 孝一
    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講演論文集 28 28 387 - 388 特定非営利活動法人 超音波エレクトロニクス協会 2007年 [査読無し][通常論文]
  • 中里 慎吾, 川村 洋平, 浅香 充慶, 大川 浩一, 水谷 孝一
    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講演論文集 28 28 381 - 382 特定非営利活動法人 超音波エレクトロニクス協会 2007年 [査読無し][通常論文]
  • 浅香 充慶, 川村 洋平, 中里 慎吾, 大川 浩一, 水谷 孝一
    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講演論文集 28 28 213 - 214 特定非営利活動法人 超音波エレクトロニクス協会 2007年 [査読無し][通常論文]
  • 河 宜成, 川村 洋平, 水谷 孝一, 大川 浩一, 浅香 充慶
    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年10月30日 [査読無し][通常論文]
  • 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 2006年03月27日 [査読無し][通常論文]
  • 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 2006年03月27日 [査読無し][通常論文]
  • 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 2006年03月27日 [査読無し][通常論文]
  • 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 2006年03月27日 [査読無し][通常論文]
  • 大川 浩一, 中里 槙吾, 矢吹 順平, 川村 洋平, 有瀬 一郎, 上松 和義, 佐藤 峰夫
    ソノケミストリー討論会講演論文集 15 13 - 14 日本ソノケミストリー学会 2006年 
    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.
  • 中里 槙吾, 大川 浩一, 川村 洋平, 上松 和義, 佐藤 峰夫
    ソノケミストリー討論会講演論文集 15 81 - 82 日本ソノケミストリー学会 2006年 
    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.
  • Youhei Kawamura, Ken Ito, Kinsuke Yamamoto, Tatsuo Sakakibara
    13th International Congress on Sound and Vibration 2006, ICSV 2006 6 4915 - 4922 2006年 
    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.
  • Eui Seong Ha, Youhei Kawamura, Koichi Mizutani
    13th International Congress on Sound and Vibration 2006, ICSV 2006 6 4722 - 4729 2006年 
    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.
  • Yu Ito, Youhei Kawamura, Koichi Muzutani, Senro Kuraoka
    2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13 1561 - + 2006年 [査読有り][通常論文]
     
    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.
  • Yuki Kudo, Nobuharu Aoshima, Youhei Kawamura
    2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13 213 - + 2006年 [査読有り][通常論文]
     
    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.
  • Makoto Nagayama, Youhei Kawamura
    2006 SICE-ICASE INTERNATIONAL JOINT CONFERENCE, VOLS 1-13 4016 - + 2006年 [査読有り][通常論文]
     
    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.
  • Ha Eui Seong, Kawamura Youhei, Mizutani Koichi, Okawa Koichi, Asaka Michinori
    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講演論文集 27 27 245 - 246 特定非営利活動法人 超音波エレクトロニクス協会 2006年 [査読無し][通常論文]
  • Kawamura Youhei, Asaka Michinori, Ha Eui Seong, Ito Yu, Okawa Koichi, Mizutani Koichi
    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講演論文集 27 27 243 - 244 特定非営利活動法人 超音波エレクトロニクス協会 2006年 [査読無し][通常論文]
  • Makoto Nagayama, Youhei Kawamura, Masuyuki Ujihira
    SAE Technical Papers 2006年 [査読有り][通常論文]
     
    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]
  • 西山 えるむ, 川村 洋平, 山近 哲志
    応用力学論文集 9 531 - 538 土木学会 2006年 [査読有り][通常論文]
  • F.Ito, D.Akhmetov, M.Komazaki, H.Tachikawa, M.Ujihira, K.Ohara;Y, Kawamura, 川村, 洋平
    SICE 41 9 SICE 2005年09月 [査読有り][通常論文]
  • 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 2005年06月 [査読有り][通常論文]
     
    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.
  • 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 2005年06月 [査読有り][通常論文]
     
    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.
  • 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 2005年03月28日 [査読無し][通常論文]
  • 水谷 孝一, 柏崎 賢一, 糸賀 一也, 澤村 喬平, 工藤 功介, 川村 洋平
    春季大会講演集. I, 資源編 17 1 91 - 92 2005年03月28日 [査読無し][通常論文]
  • 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 2005年03月28日 [査読無し][通常論文]
  • 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 2005年03月28日 [査読無し][通常論文]
  • 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 2005年03月28日 [査読無し][通常論文]
  • 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年 
    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.
  • Y. Kawamura, N. Aoshima, M. Tsurushima, Y. Ito, K. Mizutani, M. Ujihira
    Proceedings of the SICE Annual Conference 427 - 432 2005年 
    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.
  • 川村 洋平, 野呂 浩介, 河 宜成, 水谷 孝一, 青島 伸治
    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講演論文集 26 26 437 - 438 特定非営利活動法人 超音波エレクトロニクス協会 2005年 [査読無し][通常論文]
  • 鶴島 守, 川村 洋平, 伊藤 優, 水谷 孝一, 氏平 増之, 倉岡 千郎, 青島 伸治
    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講演論文集 26 26 431 - 432 特定非営利活動法人 超音波エレクトロニクス協会 2005年 [査読無し][通常論文]
  • 川村 洋平, 河 宜成, 野呂 浩介, 水谷 孝一, 青島 伸治
    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講演論文集 26 26 429 - 430 特定非営利活動法人 超音波エレクトロニクス協会 2005年 [査読無し][通常論文]
  • 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年 [査読有り][通常論文]
     
    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.
  • 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年 [査読有り][通常論文]
     
    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.
  • 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年 [査読有り][通常論文]
     
    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.
  • 鶴島 守, 川村 洋平, 伊藤 優
    応用力学論文集 8 951 - 958 土木学会 2005年 [査読有り][通常論文]
  • 山近 哲志, 川村 洋平, 氏平 増之
    応用力学論文集 8 531 - 538 土木学会 2005年 [査読有り][通常論文]
  • 川村 洋平, 氏平 増之, 青島 伸治, 伊藤 史人, アクメトフ ダウレン
    土木学会論文集 = Proceedings of JSCE 0 763 107 - 117 公益社団法人 土木学会 2004年06月20日 [査読有り][通常論文]
     
    ダンプトラックやパワーショベルといった重機は土木建設現場や資源開発現場において不可欠な存在である. 現在, 簡易で確実かつ迅速に失火気筒を判定できる実用的判定法の開発が望まれている. 本研究ではエンジンブロックの2箇所から計測した加速度波形をウェーブレット解析することにより簡易, 確実, 迅速に失火気筒を判定できるかどうか調べた. 実験の結果, エンジンをベンチに設置した基礎実験により人為的に発生させた12気筒すべての失火状態を時間-周波数マップから読み取ることが可能となっている. 実際に不調が認められている実機の実条件下でのフィールド実験においても, その失火気筒の判定が可能であったことを示す.
  • 氏平 増之, 中島 一平, 川村 洋平, 川北 稔
    応用地質 45 1 13 - 21 一般社団法人日本応用地質学会 2004年04月10日 [査読有り][通常論文]
     
    調査目的の被写体が遠すぎたり危険で近寄れない場合には, 撮影距離とレンズの焦点距離を測定しておき, 写真から簡易的に被写体寸法を算定する方法がある. しかし, 地質調査等で斜面を脚部から撮影するような場合は一枚の写真内に遠い位置の物体と近い位置の物体の両方が写されていることが多く, 画像上で測定した寸法に結像倍率を乗ずるだけでなく斜面の傾斜を考慮した傾斜補正が必要である. 本研究では, 傾斜補正法を明らかにするとともに, 六角形板の寸法, 平板上に450個分布させた岩石の寸法, 発破ずりの寸法に関する補正試験を行った. その結果, 六角形の平板については実寸法の0.85~1.04倍の補正値が得られ, 発破ずりに関しては実測した粒度特性値の0.94倍の補正値が得られたと述べた. 以上, 本論で述べた被写体寸法測定時の傾斜補正法は有効といえる.
  • 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 2004年03月29日 [査読無し][通常論文]
  • 川村 洋平, 氏平 増之, 青島 伸治, 伊藤 史人, アクメトフ ダウレン F.
    計測自動制御学会論文集 40 2 257 - 266 公益社団法人 計測自動制御学会 2004年02月29日 [査読有り][通常論文]
     
    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.
  • Y. Kawamura, M. Ujjhira, M. Nagayama, N. Aoshima, F. Ito, D. Akhmetov
    Proceedings of the SICE Annual Conference 153 - 156 2004年 [査読有り][通常論文]
     
    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.
  • Youhei Kawamura, Mamoru Tsurushima, Nobuharu Aoshima, Koichi Mizutani
    IECON 2004: 30TH ANNUAL CONFERENCE OF IEEE INDUSTRIAL ELECTRONICS SOCIETY, VOL 2 2 1795 - 1798 2004年 [査読有り][通常論文]
     
    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.
  • 川村 洋平, 鶴島 守, 水谷 孝一, 倉岡 千朗, 青島 伸治
    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講演論文集 25 25 143 - 144 特定非営利活動法人 超音波エレクトロニクス協会 2004年 [査読無し][通常論文]
  • 伊藤 史人, 氏平 増之, 安池 雅之, 川村 洋平, 樋口 澄志, 山田 孝, アクメトフ ダウレン, 駒崎 征明
    応用地質 44 4 223 - 233 一般社団法人日本応用地質学会 2003年10月10日 [査読有り][通常論文]
     
    最近公表された和歌山県天鳥橋西地区における岩盤モニタリングの結果, 1997年の北海道島牧村第2白糸トンネル巻き出し部の岩盤崩落事故等を参考にすると, 大規模落石や岩盤崩落の前には崩壊岩体境界部から大小の落石が発生し, その頻度が高まると考えられる. 著者らは, 前兆的に発生するこの小礫, 岩塊の落下頻度をモニタリングすることが大規模落石~岩盤崩壊の予知に有効と考えている. 本研究では, スチールワイヤ型ケーブルセンサと衛星電話を組み合わせた落石予検知システムの落石検知能力に関する実験的研究を行った. 衛星電話を経由しての遠隔計測により, 「スチールワイヤ型ケーブルセンサを弾性波伝播媒体となる防護網等がない斜面に敷設した場合においても, 大小の岩塊, 小礫の落下頻度と落下源をモニタリングできること」 を明らかにした. また, 現場側PCに保存している15秒分のデータを分析することにより「落下群の落下速度を求められること」, 「センサ敷設間隔は10mまで広げ得ること」等を明らかにした.
  • 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年 [査読有り][通常論文]
     
    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
  • 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年 [査読有り][通常論文]
     
    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.
  • M. Ujihira, T. Hzuka, Y. Kawamura, M. Kawakita
    International Journal of Surface Mining, Reclamation and Environment 16 3 230 - 244 2002年09月 [査読有り][通常論文]
     
    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.
  • 川村 洋平, 氏平 増之, 桐本 賢太, 緒方 純俊, 中村 祥一, 樋口 澄志
    資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan 118 5 399 - 406 一般社団法人 資源・素材学会 2002年06月25日 [査読有り][通常論文]
     
    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.
  • 氏平 増之, 飯塚 岳彦, 川村 洋平, 川北 稔
    応用地質 43 1 2 - 13 一般社団法人日本応用地質学会 2002年04月10日 [査読有り][通常論文]
     
    地質調査等で, 目的の被写体が高すぎる, 遠すぎる, 危険で近寄れない場合には被写体のそばにスケールを置くことができない. しかし, フィルムスキャナや画像処理ソフトウエアが進歩し, ノンプリズム型測距儀が普及してきた今日では, このような場合でも被写体の寸法を画像を用いて測定することが可能と考えられる. 本研究では, レンズの結像倍率式を用いて被写体寸法を間接的に求めようとするときに必要な焦点距離別の撮影限界距離と画像のひずみを, 実測データに基づき検討した. 本論で明らかにした主な内容は以下のようである. (1) ±5%以内の被写体寸法測定誤差を許容すれば, 焦点距離f=100mm以上のレンズを用いることで300m遠方までの被写体寸法を測れる. (2) 画像のひずみは, 焦点距離f=100mm以上のレンズを用いた場合1.0~2.0%以下である. (3) 放射線の入った同心円状のひずみ補正用図形を撮影した後, 画像上の点のあるべき位置からの変位量と光軸からの距離の関係式を用いることで被写体寸法を補正できる. (4) ほかに簡便な方法がない場合にカメラと測距儀を用いて間接的に被写体寸法を測定しようとする本論の方法は有用である. このとき, 距離の正しい測定, 焦点距離が正確なレンズの使用, 被写体像の微小寸法の正確な測定を行うことが重要である.
    本研究では, レンズの結像倍率式を用いて被写体寸法を間接的に求めようとするときに必要な焦点距離別の撮影限界距離と画像のひずみを, 実測データに基づき検討し, 撮影限界距離とひずみ補正法を具体的に示した. 本論で明らかにした内容をまとめると以下のようである.
    1) 地質調査等でカメラを用いて被写体寸法を測定しようとする場合, 被写体寸法はフィルム上の被写体像の微小寸法をフィルムスキャナで測り, これに理論倍率を乗じて求める. このとき, スキャナによる微小寸法測定誤差と画像のひずみが目的とする被写体寸法測定誤差の主な原因になる.
    2) 実測により被写体寸法測定誤差の95%信頼限界を計算し, レンズの焦点距離ごとの撮影限界距離を示した. ±5%以内の測定誤差を許容すれば, 焦点距離f=100mm以上のレンズを用いることで300m遠方までの被写体寸法を測ることができる.
    3) 画像のひずみについて検検討し, f=36, 50mm等, 焦点距離が短いレンズを用いた場合に大きいひずみが現われることを定量的に示した. やはり焦点距離f=100mm以上のレンズを用いることでひずみを1.0~2.0以下の範囲内に抑えれる.
    4) やむを得ずf=36, 50mm等短い焦点距離のレンズを用いる場合には, ひずみを補正することが必要である. 放射線の入った同心円状の図形を撮影した後, 画像上の点のあるべき位置からの変位量と光軸からの距離の関係式を用い, 被写体寸法を補正できる.
    5) フィールドにおいて目的とする被写体の寸法を測定しようとする場合, 他に簡便な方法がないときにはカメラと測距儀を用いて間接的に測定しようとする本方法が有用である. ただし, 距離の正しい測定, 焦点距離が正確なレンズの使用, 被写体像の微小寸法の正確な測定を行うことが重要である.
  • 桐本 賢太, 川村 洋平, 氏平 増之, 緒方 純俊
    計測自動制御学会論文集 = Transactions of the Society of Instrument and Control Engineers 38 2 230 - 232 計測自動制御学会 2002年02月28日 [査読有り][通常論文]
  • 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年 [査読有り][通常論文]
  • 駒崎 征明, 浦田 健司, 伊藤 史人, 氏平 増之, 徳永 哲信, 今野 慎也, 川村 洋平, 樋口 澄志, 川北 稔
    応用地質 42 5 264 - 273 一般社団法人日本応用地質学会 2001年12月10日 [査読有り][通常論文]
     
    著者らはケーブルセンサを用いた落石監視システムについて研究を進めてきた. しかし, ケーブルセンサ自体の破断強度は低く, そのまま実環境に敷設するには不十分である. したがって改良型として, ケーブルセンサをスチールワイヤの中心部に巻き込み補強したスチールワイヤ型ケーブルセンサ (SWCS) を提案している. 本研究では, SWCSを実斜面に敷設し実施したフィールド研究の結果, 次の事項が明らかになった. (1) 加速度計をSWCSに取り付け, その外周を手動により打撃する感度試験を行った結果, SWCSの出力電圧と加速度の関係はベキ関数式で示せる. また, この式を用いSWCSの出力電圧波形を加速度波形に変換することができ, センサごとの感度の違いがクリアできることを確認した. (2) 実斜面に格子状に敷設したSWCSは増幅倍率2倍で十分な出力電圧が得られた. また, 各chの出力電圧波形の立ち上がり時刻は落石の下方落下に伴い時間ずれが生じる. この立ち上がり時刻と出力波形により, 落石の落下挙動としての跳躍運動, 衝突, 落下軌跡等を読み取ることが可能である. さらに, トポグラフ表示により, 落石挙動を視覚的に把握できる. (3) SWCSの出力波形の立ち上がり時刻を結ぶ曲線から, 落石特性値 (最大速度残存係数: α, 等価摩擦係数: μ, 脚部における落下速度: V, 並進運動エネルギー: E) を算出でき, 防護工の設計に有効である. また, SWCSを現場に用い長期観測することで, 前兆としての大小の落石の累積頻度を計測することが実用上可能となる.
  • 川村 洋平, 氏平 増之, 樋口 澄志, 中村 祥一, 駒崎 征明, 伊藤 忠人
    資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan 117 6 485 - 493 一般社団法人 資源・素材学会 2001年06月25日 [査読有り][通常論文]
     
    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.
  • 氏平 増之, 川村 洋平, 樋口 澄志, 佐藤 昌志, 今野 久志, 駒崎 征明, 伊藤 史人
    応用地質 42 1 15 - 23 一般社団法人日本応用地質学会 2001年04月10日 [査読有り][通常論文]
     
    振動検出用ケーブルセンサは, 大規模岩盤崩壊に先立つ前兆的小崩落や落石を検知するうえで, また施工時の斜面監視等に有用なセンサであると考えられる. しかし, その破断荷重は0.4~0.5kNであり, そのまま実環境に敷設した場合破断の可能性がある. 著者らは, ケーブルセンサの引張強度を補強するために元のケーブルセンサをスチールワイヤの中心に巻き込んだスチールワイヤ (SW) 型ケーブルセンサを提案している. この場合, ケーブルセンサを取り巻くストランド (鋼線の束) が緩衝材の役割を果たし感度が低下すると予想された. このため, 本研究では, 異なる3つの条件下で元のケーブルセンサとSW型ケーブルセンサの感度の比較試験を行った. その結果, 次の事項が明らかになった. 1) SW型ケーブルセンサをコンクリート床や鋼製覆道等剛な構造物等に点で固定する場合, SW型ケーブルセンサの出力電圧は元のケーブルセンサより低下する. しかし, センサ全体を連続的に接着した場合には出力低下は見られない. 2) ケーブルセンサとスチールワイヤ型ケーブルセンサを地中に埋設した場合, SW型ケーブルセンサの感度は元のケーブルセンサと比較して低下する. しかし, SN比からみると信号とノイズは明瞭に判別でき十分な出力電圧が得られている. 3) SW型ケーブルセンサにおいても出力電圧と加速度の間には本論の図-8, 12, 18中の実験式に示されるようなべき関数関係が存在する. 以上の実験結果からSW型ケーブルセンサは設置状態ごとに加速度換算の実験式を求めておくことで実用に供し得ると判定している.
  • M Ujihira, F Ito, T Tokunaga, Y Kawamura, S Konno, K Higuchi, M Komazaki
    MINE PLANNING AND EQUIPMENT SELECTION 2001 57 - 62 2001年 [査読有り][通常論文]
     
    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.
  • F Ito, S Tsukazawa, M Komazaki, M Ujihira, Y Kawamura, T Tokunaga
    MINE PLANNING AND EQUIPMENT SELECTION 2001 755 - 760 2001年 [査読有り][通常論文]
     
    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.
  • Y Kawamura, M Ujihira, K Higuchi, K Kirimoto, M Komazaki, F Ito
    MINE PLANNING AND EQUIPMENT SELECTION 2001 167 - 172 2001年 [査読有り][通常論文]
     
    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年 [査読有り][通常論文]
  • 駒崎 征明, 平間 和夫, 伊藤 史人, 氏平 増之, 鈴木 新吾, 川村 洋平, 樋口 澄志
    応用地質 41 4 200 - 209 一般社団法人日本応用地質学会 2000年10月10日 [査読有り][通常論文]
     
    岩盤斜面での破壊音や落石の衝突振動を広い範囲にわたって監視できる, すなわち測定範囲を点から線, 面へ拡張できる可能性を持つセンサに振動検出用ケーブルセンサがある. この研究では, 実規模覆道内にケーブルセンサを格子状に敷設し, 「落下物の落下位置が二次元的に標定できるか」 , 「落下物の大きさを評価できるか」 , 「加速度計による測定結果との対比ではどうか」 等について実験を行った. 加えて, 新たに開発した移動通信網を用いたデータ伝送システムの動作に関する実験を行った. その結果, 次の事項が明らかになった, または確認された. (1) ケーブルセンサは高い精度を要求していなければ, 加速度計の代替センサとして利用できる. (2) 実規模の覆道においても上部に鋼球を落下させた場合, 落下位置は波形の立ち上がり, 振幅, トポグラフィのいずれによっても標定できる. (3) ケーブルセンサは6gの鋼球の落下振動を検出できる. また, ケーブルセンサからの出力電圧値から落下物重量のオーダの違いを推定できる. (4) ケーブルセンサの長さが増加すると出力の感度が落ちるが, 実験結果から仮に100mのケーブルセンサを用いても実用上十分な感度が得られる. (3) 新たに開発した落石検知システムにおける携帯電話通信網による必要なデータ量 (48Kbyte) の伝送時間は現在のところ3分以内であり, ケーブルセンサを含めた本落石検知システムは実用に供せる可能性が高い.
  • M Komazaki, K Hirama, F Ito, M Ujihira, Y Kawamura, T Tokunaga
    MINE PLANNING AND EQUIPMENT SELECTION 2000 309 - 313 2000年 [査読有り][通常論文]
     
    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.
  • M Komazaki, K Hirama, F Ito, M Ujihira, Y Kawamura, T Tokunaga
    MINE PLANNING AND EQUIPMENT SELECTION 2000 309 - 313 2000年 [査読有り][通常論文]
     
    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年 [査読無し][通常論文]
  • 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年 [査読無し][通常論文]
  • 建設機械のエンジンの異常診断に関する基礎研究
    川村, 洋平
    土木学会北海道支部論文報告集 56(A) 296-299  2000年 [査読無し][通常論文]
  • M. Komazaki, K. Hirama, M. Ujihira, S. Suzuki, H. Saeki, Y. Kawamura
    International Journal of Surface Mining, Reclamation and Environment 13 4 159 - 163 1999年 
    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年 [査読有り][通常論文]
  • 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 8th Int. Symposium on Mine Planning and Equipment Selection 539-544  1999年 [査読有り][通常論文]
  • 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年 [査読無し][通常論文]
  • 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年 [査読有り][通常論文]
     
    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年 [査読無し][通常論文]

書籍

  • Dhaka Megacity
    Kawamura,Youhei (担当:分担執筆範囲:Illustrating Quality of Life (QOL) in Dhaka City Corporation (DCC) area by integrating remote sensing and census data)
    Springer 2013年
  • よくわかる農業施設学会用語解説集,
    川村,洋平 (担当:分担執筆範囲:信号処理)
    2012年
  • 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 (担当:監修)
    超音波TECHNO 2009年03月
  • 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 (担当:監修)
    岩の力学ニュース 2009年01月
  • [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 (担当:監修)
    計測と制御 2007年10月
  • 筑波大学 川村研究室-Geo Sensing-
    川村洋平 (担当:監修)
    超音波TECHNO 2007年01月
  • 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 (担当:監修)
    超音波TECHNO 2006年09月
  • コンビナート配管における損傷探査
    川村洋平 (担当:監修)
    超音波TECHNO 2006年09月
  • 2006 SICE-ICASE International Joint Conference, Vols 1-13
    Kudo, Yuki, Aoshima, Nobuharu, Kawamura, Youhei (担当:分担執筆範囲:Study on estimation of the finite-length unknown input waveform from a given input waveform response)
    IEEE 2006年01月 (ISBN: 9788995003848)
  • 2006 SICE-ICASE International Joint Conference, Vols 1-13
    Ito, Yu, Kawamura, Youhei, Muzutani, Koichi, Kuraoka, Senro (担当:分担執筆範囲:Cepstrum analysis applied to ultrasonic reflection wave detection wave method to investigate the depth and the damage of the pile)
    IEEE 2006年01月 (ISBN: 9788995003848)
  • 2006 SICE-ICASE International Joint Conference, Vols 1-13
    Nagayama, Makoto, Kawamura, Youhei (担当:分担執筆範囲:Estimation of the engine revolution for statistical analysis of RMS value by using Prony method to detect misfiring cylinder of the diesel engine)
    IEEE 2006年01月 (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 (担当:監修)
    超音波TECHNO 2005年05月

講演・口頭発表等

  • A Magnetic Climbing Robot for Steel Bridge Inspection  [通常講演]
    Kawamura,Youhei
    The 11th World Congress on Intelligent Control and Automation 2014年 口頭発表(一般) China
  • The application of ZigBee Technology for underground Mine Communication and Monitoring Systems  [招待講演]
    Kawamura,Youhei
    Akita University Leading Program 2013 International Workshop 2013年09月 口頭発表(招待・特別) 日本 秋田 秋田大学
  • An Investigation of Radio Wave Attenuation for ZigBee Network in Underground Mines  [招待講演]
    Kawamura,Youhei
    The 3rd Int. Symposium on Soft Computing and Disaster Control 2013 2013年 口頭発表(招待・特別) Indonesia Bali
  • Underground Blasting Optimization by Artificial Intelligence Techniques  [招待講演]
    Kawamura,Youhei
    The 3rd Int. Symposium on Soft Computing and Disaster Control 2013 2013年 口頭発表(招待・特別) Indonesia Bali
  • Emergency Management with ZigBee and GIS  [招待講演]
    Kawamura,Youhei
    15th International Symposium on Computational Intelligence and Industrial Applications 2012年 口頭発表(招待・特別) Japan Sapporo
  • Development of DigBot for Monitoring the Underground Environment  [通常講演]
    Kawamura,Youhei
    15th International Symposium on Computational Intelligence and Industrial Applications 2012年 口頭発表(一般) Japan Sapporo
  • Long-Term Operation of Landslide observation System Using ZigBee Modules  [通常講演]
    Kawamura,Youhei
    The 1st International Workshop on Soft Computing and Disaster Control 2011年 口頭発表(一般) Indonesia Srabaya
  • Development of DigBot for Surveying the Underground after the Disaster  [通常講演]
    Kawamura,Youhei
    The 1st International Workshop on Soft Computing and Disaster Control 2011年 口頭発表(一般) Indonesia Srabaya
  • Underground Imaging Method Using Magnified Cross-Correlation Analysis  [通常講演]
    Ha, Euiseong, Kawamura, Youhei, Mizutani, Koichi, Kamohara, Akihiro, Okawa, Hirokazu
    28th Symposium on Ultrasonic Electronics 口頭発表(一般)
  • 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  [通常講演]
    宇津木隆裕, 川村洋平, 土方大輔
    2010年度産業応用部門大会論文集_計測自動制御学会___ 口頭発表(一般)
  • 資源開発阻害微生物の超音波処理  [通常講演]
    細川亮太, 斉藤知直, 大川浩一, 川村洋平
    資源・素材学会平成22年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    川村洋平, 田村潤平, 鎌形真伍, 持地英実
    資源・素材学会平成22年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    川村洋平, 中畑裕也, 蟹江迪子, 倉岡千郎, 大川浩一
    資源・素材学会平成22年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    大川浩一, 斉藤知直, 細川亮太, 川村洋平
    資源・素材学会平成22年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    川村洋平, 鎌形真伍, 中畑裕也, 大川浩一
    資源・素材学会平成22年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    川村洋平, 蒲原章裕, 水谷孝一, 大川浩一
    資源・素材学会,平成21年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • DIGBOT開発のための二重反転ドリル性能評価  [通常講演]
    阿部亮平, 川村洋平, 松島亘志, 村上和利, 上島和志
    資源・素材学会,平成21年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    大川浩一, 中村貴司, 菅原勝康, 川村洋平
    資源・素材学会,平成21年度秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • PVT装置における重油粘度簡易計測手法の開発  [通常講演]
    川村洋平, 安藤寛, 大川浩一, 菅井裕一, 佐々木久郎
    資源・素材学会平成21年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    蒲原章裕, 川村洋平, 大川浩一, 水谷孝一
    資源・素材学会平成21年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • Zigbeeを用いた斜面ネットワークの構築  [通常講演]
    川村洋平, 駒井雄一, 太田敬一, 倉岡千郎, 大川浩一
    資源・素材学会平成21年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    蒲原章裕, 川村洋平, 中里槙吾, 大川浩一, 水谷孝一
    資源・素材学会平成20年秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 磁界を用いた土石流中の礫の位置計測システムの提案  [通常講演]
    杉山文乃, 川村洋平, 松島亘志, 倉岡千郎, 大川浩一
    資源・素材学会平成20年秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    川村洋平, 蒲原章裕, 大川浩一, 水谷孝一
    資源・素材学会平成20年秋季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 超磁歪振動子を用いた岩盤亀裂推定に関する研究  [通常講演]
    浅香充慶, 川村洋平, 中里槙吾, 大川浩一, 水谷孝一
    資源・素材学会平成20年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    川村洋平, 蒲原章裕, 河宜成, 水谷孝一, 大川浩一
    資源・素材学会平成20年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • 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  [通常講演]
    杉山文乃, 川村洋平, 松島亘志, 倉岡千郎, 大川浩一
    資源・素材学会平成20年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • PVT装置の粘度計測システムに関する基礎研究  [通常講演]
    中里槙吾, 川村洋平, 宮川雄磨, 大川浩一
    資源・素材学会平成20年春季大会講演論文集_資源・素材学会___ 口頭発表(一般)
  • Development of Underground Mine Communication and Monitoring System by Using ZigBee Technology  [通常講演]
    Kawamura,Youhei
    8th Asian Rock Mechanics Symposium 口頭発表(一般) Japan Sapporo Rock Mechanics
  • Prediction of Blast-Induced Ground Vibration at a Limestone Quarry and On-Going Project at WASM  [招待講演]
    Kawamura,Youhei
    Rock Breakage and Fragmentation Workshop 2014 口頭発表(招待・特別) Indonesia Yogjakarta

その他活動・業績

特許

  • 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月01日
    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月07日
    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月07日
    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月
    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月
    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月20日
    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月01日
    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月01日
    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

受賞

  • 2011年 Best Cognition Award
     As Publication Co-Chairs 
    受賞者: Youhei Kawamura
  • 2011年 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年03月 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年11月 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年09月 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年10月 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年 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

共同研究・競争的資金等の研究課題

  • 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
    研究期間 : 2021年04月 -2027年03月
  • 輸送中の振動を受ける美術品の蓄積疲労予測システムの理論構築
    日本学術振興会:科学研究費助成事業 基盤研究(B)
    研究期間 : 2020年04月 -2024年03月 
    代表者 : 和田 浩, 川村 洋平, 小西 毅
  • 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
    研究期間 : 2020年10月 -2022年03月
  • テーリングダム調査を目的とした地中ドローンの開発
    日本学術振興会:科学研究費助成事業 挑戦的研究(萌芽)
    研究期間 : 2018年06月 -2021年03月 
    代表者 : 川村 洋平, 伊達 央, 澁谷 長史
     
    本申請課題は、採鉱活動の副産物となる“ずり”の貯蔵場である“テーリングダム”の内部を調査可能な地中ドローンを開発するものである。地中(粒状物質中)を自在に移動可能な地中ドローンは世界的にも見られない。抵抗の非常に大きい粒状物質中を移動できる地中ドローンの実現のために求められるコア技術は、革新的な掘削機構・推進機構およびその小型化である。本申請課題2つのコア技術を組み合わせることで、粒状物質中を自在に動き回り、必要な情報を収集することが可能となる地中ドローンを提案する。 掘削機構の開発では“ドリルビット形状の開発”を執り行った。現在のドリルビットは土用と砂用が共用であり、砂に対して最適な形状とは言い難い。粘性のない砂では、よりプロペラに近い形状が望まれ、また、ドリル自体からの推進力も期待できる。そこで、平成30年度は一般的な文献による知識から砂用ドリルビット形状を算出し、3Dプリンタで作製、評価した。また、計算結果と合わせて、金属製のドリルビットを作製した。 推進機構では2次元運動ヘビ型推進機構つまりサーボモータを直列に連結した多関節駆動装置を設計し、プロトタイプを製作した。最大トルク4.8Nmの5つのサーボモータを関節とした。間接 ピッチ・ヨー2自由度を持つ関節ユニットを開発した際、主体的な動きと補助的な動きを明確にモデリングすることにより、関節モーターの要求トルクに制限を設けた。反力の強い土に対してはコンサーティーナ(アコーディオン)運動を、流体のような挙動を示す砂に対しては蛇行運動を実現できるよう、制御装置を設計した。また、コンサーティーナ運動の際に、より強い反力を得るよう、アンカリング機構を追加で設けた。蛇行運動においてはサーペノイド曲線をその運動の支配的な運動原理とした。
  • 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:
    研究期間 : 2020年04月 -2021年03月
  • AIによるトンネリング技術の開発
    鹿島建設:
    研究期間 : 2019年04月 -2021年03月
  • ハイパースペクトル撮影技術の開発
    五洋建設:
    研究期間 : 2019年03月 -2020年04月
  • 強震動と液状化の複合作用を受けるライフラインネットワークの被害推定システムの開発
    日本学術振興会:科学研究費助成事業 基盤研究(A)
    研究期間 : 2016年04月 -2020年03月 
    代表者 : 庄司 学, 吉見 雅行, 川村 洋平, 永田 茂, 八木 勇治, 北原 格, 丸山 喜久, 先名 重樹
     
    平成30年度においては,1番目の研究目的を達成するために,本研究を通じて蓄積してきた1995年兵庫県南部地震から2018年北海道胆振東部地震に至る被害ビックデータに基づいて,被害推定システムに組み込む指標の体系的な分析を行なった.上・下水道埋設管及び通信埋設管に対象を絞った上で,埋設管の属性を表わすネットワークデータと,ボーリング調査,土質試験,透水試験,表面波探査等による埋設地盤データをマッチングさせ,ネットワークデータを埋設地盤データの特徴量で類型化した.研究代表者の庄司と研究分担者の永田及び先名がこのパートを担当した.次に,2016年熊本地震を対象とした場合のネットワーク敷設下の工学的基盤へのサイト波を有限差分計算に基づき推計した上で,熊本県益城町エリア等を対象として,ネットワークの埋設地盤に対する有効応力解析の結果を前述の研究パートと連結し,指標の精度向上に関する検討を行なった.研究分担者の八木並びに吉見が震源過程並びに地下構造のモデル化の観点からこのパートを担当した. 併行して,2番目並びに3番目の研究目的を達成するために,被害推定システムのユーザーとなる事業者や自治体の観点から見たシステム要件を踏まえ,a. 想定されるハザード情報,b. ハザードに暴露されるネットワーク情報,及び,c. ネットワークの被害情報の3タイプの「ユーザー情報」のわかりやすさと魅せ方を併せ持つ被害推定システムの開発を試みた.特に,3番目の研究目的を達成するために,ライフラインネットワークに関わる事業者や自治体の中から茨城県や熊本県,仙台市等を候補として,システムの実装に関する検討を行なった.
  • 美術品・輸送機関・梱包資材の振動特性情報を集積した安全輸送のためのシステム構築
    日本学術振興会:科学研究費助成事業 基盤研究(B)
    研究期間 : 2016年04月 -2020年03月 
    代表者 : 和田 浩, 川村 洋平, 松井 敏也
     
    2018年度は、まず美術品の陸上輸送における輸送環境への走行路面の影響、走行速度の影響を検証した。基本的に車両速度が高いほど振動レベルは大きくなり、また、首都高速道路等の高架における伸縮接手箇所がトラック荷台上で生じる振動への影響が大きいことを検証した。付随する成果として車両の個体差、荷台上の位置による差異も考慮すべき因子であることも判明した。これらの成果は美術品の荷台への積込み位置を厳密に選択する際に有用なデータとなり得る。 また、これまでほぼ明らかにされなかった海上輸送時の環境データを解析し、その特徴を捉えることができた。海上航海中は非常に安定した輸送環境であったが、乗船および下船時にやや大きな振動レベルが生じることも検証した。 美術品の梱包に緩衝材として多用されるポリエチレンフォーム材の振動応答特性の評価試験によってその特性を検証した。具体的には緩衝材への静的荷重が大きいほど共振周波数が低周波側へシフトし、また緩衝材へ入力される振動加速度が大きいほど共振周波数が低周波側へシフトする特性を把握できた。この検証により、緩衝材の特性を評価する手法の一般化および評価に基づく梱包設計の手順を提案することができた。 さらに、美術品の素材が振動を繰り返し受けることによる損傷について、損傷に至るまでの加振回数と振動加速度との関係がS-N曲線によって表現できることを検証した。この検証が美術品の素材には輸送によって蓄積疲労現象が生じることに関する科学的な根拠となった。 最後に、これまでの研究成果をまとめ、美術品の陸上、海上、航空輸送時に生じる振動と衝撃の評価手法に関する新たな指標として"STAY Index 1.0"を定義し、提案することができた。 以上を、学会等発表、論文発表として成果をとりまとめ、社会への公表を行った。
  • アンコール遺跡群における予防的保存に資する劣化・変形・環境観測システムの構築
    日本学術振興会:科学研究費助成事業 基盤研究(B)
    研究期間 : 2016年04月 -2020年03月 
    代表者 : 川村 洋平, 伊藤 豊, 中川 武, 水谷 孝一, 松井 敏也, 北原 格, 山田 俊亮, 河崎 衣美, 新谷 眞人
     
    開始から3年度目になる平成30年度は、Wi-Fiアドホックを活用した准リアルタイムデータ回収・転送システムをアンコールトムバイヨン寺院に実装した。観測対象として、岩石コアの暴露台を准リアルタイム観測することとし、カメラおよび各種センサ、簡易データロガ、アクセスポイントを現地に設置した。また、前年からの引き続きとして通信アプリの改善に努め、バックグラウンドではないが簡単なスマートフォン操作にてデータが伝送が可能となるようにアプリを再設計・実装した。現地調査員に本アプリがインストールされたスマートフォンを携帯させ、日々のモニタリングデータを集約している。また、事務所からクラウドにてモニタリングデータをアップロードし、遠く離れた日本にてそのデータを確認できるようクラウドシステムを現地事務所に設置した。これにより定期的な長期モニタリングが可能となった。現在はデータの収集に努めている。 浮き彫り劣化を検知するための3次元モデル生成手法に関しては、対象とする石柱(浮き彫り有り)を特定し、平成29年からの1年間の経年変化を解析している。また、撮影時期の違う映像からの3次元モデル復元手法を新たに開発し、3次元モデルによる劣化検知の手法にロバスト性を持たせている。また、現在、アーカイブしたモデルからクラスタリング技術により、ノイズと実際の変化を判断しノイズを除去する手法を開発している。 上記の3次元計測とWi-Fi無線データ通信が実装できたことから、今後の長期モニタリングの可能性が高まっている。
  • 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
    研究期間 : 2019年04月 -2020年03月
  • 振動解析による掘削補助装置の開発
    MMCリョウテック:
    研究期間 : 2018年04月 -2020年03月
  • 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)
    研究期間 : 2013年 -2016年 
    代表者 : 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
    研究期間 : 2011年 -2013年 
    代表者 : 安信誠二
     
    分担者
  • Fundamental Study on Non-destructive Testing Method for Foundation Pile using Giant-magnetostriction Vibrator
    研究期間 : 2013年 
    代表者 : 川村洋平
  • Improving Student’s Strategic and Technical Skills through a Meaningful Interaction with Mining Industry
    Institute of Mining & Metallurgy:
    研究期間 : 2013年 
    代表者 : 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
    日本学術振興会:科学研究費助成事業 挑戦的萌芽研究
    研究期間 : 2011年 -2012年 
    代表者 : 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
    研究期間 : 2010年08月 -2011年07月 
    代表者 : 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
    研究期間 : 2010年04月 -2011年03月 
    代表者 : 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
    研究期間 : 2009年07月 -2011年03月 
    代表者 : 川村洋平
  • 日本学術振興会:科学研究費助成事業 若手研究(B)
    研究期間 : 2010年 -2011年 
    代表者 : 大川 浩一, 川村 洋平, 香田 忍, 佐々木 久郎, 菅井 裕一
     
    超音波を用いてオイルサンドからビチューメンを水溶液中で分離した。有機溶剤を使用せずに、できるだけ低温にて高効率で分離回収することを目標とした。超音波は分散作用や剥離作用が期待できる28kHzと化学作用が期待できる200kHzを使用した。溶液温度は45℃と85℃で行った。45℃では28kHzのみビチューメンが回収できた。85℃ではビチューメンの粘度が温度上昇に伴って低下したために、剥離作用が強い28kHz、弱い200kHzともに回収が可能であった。過酸化水素と超音波の併用についても実験を行ったところ、100ppm以上の添加で良好な結果が得られた。過酸化水素由来の酸素ガスがオイルサンド表面に付着することが良好な結果を導いた。200kHzの超音波による化学作用で生成した過酸化水素は、15分照射で10ppm程度であったため十分には寄与しなかった。しかしながら、高周波数超音波は照射による生成気泡数が多く、気泡圧壊に伴う剥離作用の領域が広いため、80℃以上の環境では過酸化水素と併用することでオイルサンドからビチューメンを高効率で回収可能であることが明らかになった。
  • 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
    研究期間 : 2011年 
    代表者 : 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
    研究期間 : 2011年 
    代表者 : 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
    研究期間 : 2009年07月 -2010年03月 
    代表者 : 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
    研究期間 : 2008年09月 -2010年03月 
    代表者 : 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
    研究期間 : 2010年 -2010年 
    代表者 : 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
    研究期間 : 2008年08月 -2009年03月 
    代表者 : 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
    研究期間 : 2007年12月 -2008年03月 
    代表者 : 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
    研究期間 : 2007年12月 -2008年03月 
    代表者 : 川村洋平
     
    請負研究
  • 日本学術振興会:科学研究費助成事業 若手研究(B)
    研究期間 : 2007年 -2008年 
    代表者 : 大川 浩一, 川村 洋平, 佐藤 峰夫, 上松 和義, 佐々木 久郎, 香田 忍, 安田 啓司, 菅原 勝康
     
    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。
  • 日本学術振興会:科学研究費助成事業 基盤研究(B)
    研究期間 : 2006年 -2008年 
    代表者 : 山田 恭央, 松島 亘志, 川村 洋平, 今泉 文寿, 倉岡 千郎, 小長井 一男, 竿本 英貴
     
    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。
  • 日本学術振興会:科学研究費助成事業 若手研究(B)
    研究期間 : 2006年 -2008年 
    代表者 : 川村 洋平
     
    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)
    研究期間 : 2006年 -2008年 
    代表者 : 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
    研究期間 : 2006年10月 -2007年03月 
    代表者 : 川村洋平
     
    奨学寄附金
  • 大規模空間における作物生育環境センシンググリッドの開発研究
    日本学術振興会:科学研究費助成事業 基盤研究(B)
    研究期間 : 2005年 -2007年 
    代表者 : 水谷 孝一, 若槻 尚斗, 川村 洋平, 佐瀬 勘紀, 奥島 里美, 石井 雅久, 増山 裕之
     
    本研究は大規模空間における作物生育環境における様々のパラメータをモニタリングするための新しい手法を提案するものである。大規模空間において気温や風速などをモニタリングする場合,従来は多数のセンサを配置する必要があった。音響波は気温や風速を反映して見かけ上の音速が変化することに着目し、測定のための理論を整備した(第2章)。これに基づき,音波伝搬時間を精密に測定することにより音波の伝搬経路に沿った気温や風速の空間平均値を測定することができる音響波プローブを構成した(第3章)。音響波プローブを用いて実際に作物の生育環境のモニタリングの一環として,ハウス内温度・霧・浅層地中探査及び土質評価を行った(第4章)。大規模空間での計測に対応するため,音響波プローブの長基線化とセンサ間での情報の授受に無線ネットワークを用いることによりネットワークセンサを構成しシステム全体のシンプル化を図った(第5章)。ネットワークセンサを用いて生育環境パラメータの分布測定を行った。音響センサを対象領域の周囲に配置し,CT法により風向・風速分布および温度分布のモニタリングが可能であることを示した(第6章)。さらなる大規模化に対応し空間における生育環境のパラメータを系統的にモニタリングするため,ネットワークセンシンググリッドによる計測を提案した。これは対象空間内に音響センサをグリッド状に分散配置し,任意の音響センサの組み合わせでパラメータを取得し,測定値をコントローラに集約するものである。ユニットセルの考え方を導入することによりシステム全体を高い自由度で構成できる。実験では一つのユニットセル内でマトリクス法を用いて温度分布を求めている(第7章)。 本研究で得られた成果は,大規模植物工場における環境制御,就業者の快適な労働環境の確保,収穫量の増加などにつながり,ひいては施設園芸技術・広く産業の発展に貢献できるものである。
  • ローテータ方式杭工法に関する研究
    (株)丸順重工:その他
    研究期間 : 2005年10月 -2006年03月 
    代表者 : 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
    研究期間 : 2005年10月 -2006年03月 
    代表者 : 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
    日本学術振興会:科学研究費助成事業 若手研究(B)
    研究期間 : 2004年 -2005年 
    代表者 : 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)
    研究期間 : 2005年 
    代表者 : 川村洋平
  • 移動通信網を用いた重機管理システムの開発

大学運営

委員歴

  • 2021年07月 - 現在   JOGMEC   海洋鉱物資源開発検討委員会 委員
  • 2020年04月 - 現在   JOGMEC   基礎研究委員会 委員
  • 2020年04月 - 現在   東京都 インターネット環境改善事業検証委員会   委員
  • 2020年04月 - 現在   Journal of MMIJ   論文編集委員
  • 2019年04月 - 現在   沖縄県大東地区情報通信基盤整備推進事業適正化委員会   オブザーバー
  • 2018年01月 - 現在   Arabian Journal of Geosciences   Editor
  • 2019年01月 - 2020年12月   MINE PLANNING & EQUIPMENT SELECTION   International Committee
  • 2009年   超音波シンポジウム2009   運営委員
  • 2008年   超音波シンポジウム2008   運営委員
  • 2008年   資源・素材学会   開発機械部門委員
  • 2008年   計測自動制御学会   SICE プログラム委員
  • 2007年   超音波シンポジウム2007   実行委員
  • 2007年   計測自動制御学会   学会賞委員
  • 2006年   超音波シンポジウム   運営委員会 委員
  • 2006年   計測自動制御学会   学会賞委員
  • 2004年   資源・素材学会   開発機械部門委員
  • 2004年   計測自動制御学会   産業論文委員 幹事
  • 2003年   計測自動制御学会   産業論文委員
  • 2003年   計測自動制御学会   計装技術交流部門委員
  • 2003年   計測自動制御学会   産業論文委員 幹事

社会貢献活動

  • 三菱商事研修(鉱山工学)
    期間 : 2020年11月 - 現在
    役割 : 講師
    主催者・発行元 : 三菱商事
  • 帯広柏葉高校出前講義(スマートマイニング)
    期間 : 2020年06月 - 現在
    役割 : 講師
    主催者・発行元 : 帯広柏葉高校
  • 住友商事研修(鉱山工学)
    期間 : 2019年11月 - 現在
    役割 : 講師
    主催者・発行元 : 住友商事
  • 院内銀山を利活用した地域発展
    期間 : 2017年10月 - 現在
    役割 : 助言・指導
    主催者・発行元 : 湯沢市
  • 学際的資源開発研究会(会長)
    期間 : 2017年 - 現在
    役割 : 企画
    主催者・発行元 : 川村洋平
  • 防災テクノロジーの進化
    期間 : 2019年08月 - 2019年09月
    役割 : 講師
    主催者・発行元 : 秋田大学
    イベント・番組・新聞雑誌名 : 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
    期間 : 2019年
    役割 : 講師
    主催者・発行元 : 秋田大学

メディア報道

  • 製鉄でもCO2減豪中連携(分析)
    報道 : 2019年11月
    執筆者 : 本人以外
    番組・新聞雑誌 : 日本経済新聞
    コメント 新聞・雑誌
  • 5年で大化け!サイエンス&ベンチャー105発
    報道 : 2019年10月
    執筆者 : 本人以外
    番組・新聞雑誌 : 週刊 ダイヤモンド
    月面開発 新聞・雑誌
  • 秋田大アフリカ資源シンポ開く
    報道 : 2018年12月
    執筆者 : 本人以外
    番組・新聞雑誌 : 日刊産業新聞
     新聞・雑誌
  • どうする地域活性化
    報道 : 2018年12月
    番組・新聞雑誌 : 秋田さきがけ新報
     新聞・雑誌
  • バーチャルで見る 院内銀山と院内の町並み
    報道 : 2018年04月
    執筆者 : 本人以外
    発行元・放送局 : ABSラジオ
    番組・新聞雑誌 : Radipal
     テレビ・ラジオ番組
  • 鉱山VR
    報道 : 2017年12月
    発行元・放送局 : AKT秋田テレビ
    番組・新聞雑誌 : プライムニュース秋田
     テレビ・ラジオ番組

その他

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


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