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Wada, Yuki*; Enoto, Teruaki*; Nakamura, Yoshitaka*; Morimoto, Takeshi*; Sato, Mitsuteru*; Ushio, Tomoo*; Nakazawa, Kazuhiro*; Yuasa, Takayuki*; Yonetoku, Daisuke*; Sawano, Tatsuya*; et al.
Journal of Geophysical Research; Atmospheres, 125(4), p.e2019JD031730_1 - e2019JD031730_11, 2020/02
Times Cited Count：19 Percentile：85.61(Meteorology & Atmospheric Sciences)Wada, Yuki*; Enoto, Teruaki*; Nakamura, Yoshitaka*; Furuta, Yoshihiro; Yuasa, Takayuki*; Nakazawa, Kazuhiro*; Morimoto, Takeshi*; Sato, Mitsuteru*; Matsumoto, Takahiro*; Yonetoku, Daisuke*; et al.
Communications Physics (Internet), 2(1), p.67_1 - 67_9, 2019/06
Times Cited Count：35 Percentile：91.67(Physics, Multidisciplinary)Sakai, Ryutaro; Takeda, Seiji; Munakata, Masahiro; Kimura, Hideo
JAEA-Research 2013-006, 18 Pages, 2013/07
JAEA-Research-2013-006.pdf:2.77MB
In the safety assessment for a geological disposal of radioactive waste, it is important to establish validation methods for deep groundwater flow to estimate radionuclide migration to human environment through groundwater flow. Costal sedimentary rocks in our country provide dominant fossil water formed during sub-seabed sedimentation and chemical compositions of the water mixed with meteoric water and fossil water depend on the initial fossil water composition and groundwater flow conditions. Analytical study on the effects of groundwater flow on the mixed water quality as a indicator of its Cl/
O ratios was carried out in case of Horonobe district, where geochemical data is now being stored.
Matsui, Kunihiro; Koizumi, Norikiyo; Hemmi, Tsutomu; Takano, Katsutoshi; Nakajima, Hideo; Kimura, Satoshi*; Iijima, Ami*; Sakai, Masahiro*; Osemochi, Koichi*; Shimada, Mamoru*
IEEE Transactions on Applied Superconductivity, 22(3), p.4203005_1 - 4203005_5, 2012/06
Times Cited Count：6 Percentile：38.48(Engineering, Electrical & Electronic)JAEA is responsible for the procurement of 9 toroidal field (TF) coils as Japanese Domestic Agency. JAEA had started several trials to successfully develop technologies for the TF coil manufacture since March 2009, and performed one-third scale trials aiming at qualifying and optimizing the procedures of the TF coil fabrication. The fabricated double pancakes (DPs) were successfully put into the profile with tolerances from zero to 1.5 mm. These tolerances correspond to 0.06% accuracy in the conductor length. The geometry of the DP was changed after heat treatment. Heat treatment procedure to avoid such deformation should be developed or the change of winding geometry should be taken into account in the fabrication of the TF coils. The one-third scale DP was successfully impregnated. Although exothermal reaction is given to take place during curing in the blended resin, we successfully cured the one-third scale DP.
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo
JAEA-Research 2011-054, 19 Pages, 2012/03
JAEA-Research-2011-054.pdf:2.07MB
In the safety assessment for a geological disposal of radioactive waste, it is important to establish validation methods for deep groundwater flow system to estimate radionuclide migration to human environment through groundwater flow. This study discussed the method which estimates groundwater mixing condition and groundwater flow process using principal component analysis (PCA) to groundwater chemistry and isotopic compositions, together with data of groundwater age and trace element in case of Horonobe area. The results show that hydrochemical system can be divided into two systems: (1) three deep groundwater mixing system at depths greater than 200 to 400 m, (2) mixing area of deep groundwater and surface water at depths less than 200 to 400 m. Groundwater in the deep aquifer is suggested to be discharged at surface through Omagari Fault.
Hemmi, Tsutomu; Matsui, Kunihiro; Koizumi, Norikiyo; Nakajima, Hideo; Iijima, Ami*; Sakai, Masahiro*
Teion Kogaku, 47(3), p.172 - 177, 2012/03
The manufacturing process for the ITER Toroidal Field (TF) coil has to be demonstrated for the qualification. Since the impregnation of its insulation system is one of the qualifications, the authors performed impregnation test using cyanate-ester and epoxy blended resin, which is a candidate among resins because of its excellent resistance to radiation. To establish the insulation and impregnation procedure of the TF coil manufacturing, three types of trials were performed. (1) Impregnation tests using an acrylic model to fix the impregnation conditions; (2) Impregnation test using a metallic model to confirm that no void remains in the insulation layer after the curing in the D-shaped configuration; and (3) Insulation and impregnation trials using 1/3 scale double pancake (DP) to establish the insulation and impregnation procedure for the TF coil manufacturing, The procedure of the insulation and impregnation for the ITER TF coil was established from the results of these trials.
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo; Ooka, Masao*; Seguchi, Mariko*
JAEA-Research 2011-029, 24 Pages, 2011/11
JAEA-Research-2011-029.pdf:3.67MB
In the safety assessment for a geological disposal of radioactive waste, it is important to establish validation methods for regional groundwater flow system to estimate radionuclide migration to human environment through groundwater flow. It is necessary to validate the groundwater flow property and flow boundary, as multi-groundwater systems including the different groundwater origins are possible to exist at deep underground. This results show that mixing analysis based on hydrochemical data and spatial plotting with hydrochemical data and thermal data are applicable to validate groundwater flow pattern and groundwater flow boundary in case of Horonobe area. It also demonstrates that mixing analysis based on hydrochemical data and spatial plotting with hydrological and hydrochemical data are applicable to validate the groundwater flow property and groundwater flow boundary in case of Nagaoka area.
Kimura, Hideo; Aoyagi, Tetsuo; Sato, Taiichi; Sakai, Manabu; Hikasa, Naoki*; Suzuki, Hitoshi; Tsuji, Minoru
JAEA-Technology 2011-027, 31 Pages, 2011/09
JAEA-Technology-2011-027.pdf:2.16MB
The financial accounting and contract management system of JAEA, built on a commercial ERP package, had suffered from serious problems of high lifecycle cost, poor response, and lack of extensibility, due to the too much customization to the ERP package, and disorganized software structure. To solve those problems, three approaches were applied; (1) conducting thorough analysis of business flow and fit/gap, which enabled removing all customization brought to the ERP package; (2) dividing the system into subsystems, and clearly defining interfaces between the subsystems, which increases the transparency, extensibility and performance of the system; (3) outsourcing the development of the subsystems to multiple venders to reduce the development cost. Those approaches can be useful for developing business information systems using commercial software to save time and cost, while meeting the unique requirements of an organization.
Sakai, Ryutaro; Takeda, Seiji; Kimura, Hideo; Matsuba, Hisashi*
JAEA-Data/Code 2011-005, 107 Pages, 2011/06
JAEA-Data-Code-2011-005.pdf:2.74MB
In the safety assessment for a geological disposal of radioactive waste such as high-level radioactive waste, it is necessary to estimate the hydrological environmental changes affected by external factors such as long-termed earthquake activity and volcanic activity. Therefore it is important to perform the informations including a wide range of future processes and conditions of engineered barriers and geosphere in a systematic manner and to construct scenarios considering external factors. Generation of geological and climatic disruptive events such as earthquake activity, volcanic activity, uplift, subsidence, climatic change and sea-level change and propagation process of their impacts and their types are needed to be clarified in order to understand the phenomena of their influence on a disposal system in case of our country. Japan Atomic Energy Agency started to develop FEP database including the correlation of FEPs and FEP data sheet.
Ikeda, Makoto; Munakata, Masahiro; Sakai, Ryutaro; Kimura, Hideo; Jia, H.*; Matsuba, Hisashi*
Nihon Chikasui Gakkai 2011-Nen Shunki Koenkai Koen Yoshi, p.86 - 91, 2011/05
no abstracts in English
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo; Ichikawa, Yasuo*; Nakamura, Masaru*
JAEA-Research 2010-066, 20 Pages, 2011/03
JAEA-Research-2010-066.pdf:2.26MB
In the safety assessment for a geological disposal of radioactive waste, it is important to establish modelling methods and validation methods for regional groundwater flow system in the depth of 300
1000m to estimate radionuclide migration to human environment through groundwater flow system. The study discussed application of data and assessment methods for model validation based on multiple indicators such as hydrology, groundwater chemistry, temperature and age of groundwater in case of the Boso Peninsula in Chiba Prefecture where a lot of in-situ data about groundwater was measured. This results show that existing hydrochemical and thermal data are applicable to explain freshwater and saltwater distribution and groundwater flow pattern in case of regional scale. It also indicates that gravitational groundwater is likely to flow into the deep part of fresh-saltwater interface based on the exist of Na-HCO
type water above fresh-saltwater interface mixed with meteoric water and that multiple indicators are applicable to evaluate groundwater flow property and groundwater flow boundary in case of site scale region.
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo; Ooka, Masao*; Kameya, Hiroshi*; Hosoda, Koichi*
Dai-21-Kai Zenkoku Chishitsu Chosagyo Kyokai Rengokai "Gijutsu Foramu" Koenshu (CD-ROM), 2 Pages, 2010/11
no abstracts in English
Ikeda, Makoto; Munakata, Masahiro; Sakai, Ryutaro; Fuchiwaki, Hirotaka; Kimura, Hideo; Matsuba, Hisashi*
Nihon Chikasui Gakkai 2010-Nen Shuki Koenkai Koen Yoshi, p.282 - 287, 2010/11
no abstracts in English
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo
Chikasui Gakkai-Shi, 51(4), p.311 - 329, 2009/11
In order to evaluate the regional groundwater flow system, the author has investigated stream flow of 3 rivers and analyzed flow rates and chemical compositions, isotopic ratios of hydrogen and oxygen of water samples collected from wells, rivers and springs in the feeder streams area in the Yoro river basin, in Chiba Prefecture. As a result of this study, (Na)Ca-HCO type water is evaluated to be recharged from the highly permeable sand-dominant domain (Daifuku Mt.). In addition, it is estimated that the groundwater flow preferentially in direction of strike and discharge at the middle and downstream domain as Ca-HCO type water, and partially pass through fractures of low permeable alteration layer up to the surface area as evolved Na-HCO type water.
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo
JAEA-Research 2008-122, 18 Pages, 2009/03
JAEA-Research-2008-122.pdf:6.57MB
It is important to evaluate effect on the groundwater flow system by the natural phenomena in the safety assessment of geological disposal of radioactive waste through a survey of recent scientific informations. In this report we study about the scenario of sea level change effecting on the groundwater flow system which is very important for a safety of disposal facility in costal area. As a result, this study show that the non-current paleo-fresh water at present is possible to start to discharge at sea floor in the next glacial period by denudation of marine-clay sediments and to grow stagnant again in the next interglacial period by deposition of marine-clay sediments. Therefore it is important to predict the scenario considering the denudation and deposition correlated with transgression and regression that could affect the change of groundwater flow characteristics during the glacial and interglacial period.
Kimura, Hideo; Aoyagi, Tetsuo; Sakai, Manabu; Sato, Taiichi; Tsuji, Minoru
JAEA-Technology 2008-075, 32 Pages, 2008/11
JAEA-Technology-2008-075.pdf:8.29MB
JAEA developed the ERP (Enterprise Resource Planning) system at the establishment in 2005, aiming to support and enhance its business-critical task such as financial accounting and contract management. We considered the conceptual design of the next ERP system, and we implemented the prototype system to validate its effectiveness. Moreover, we implemented the simple add-on tool for rapid and easy development. At the result, we gauged the future prospects that the XML-centric system which we designed will offer high modularity, flexibility, connectivity between other systems, independence among subsystems. The simple add-on tool also demonstrated its effectiveness.
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo
JAEA-Research 2007-083, 38 Pages, 2008/01
JAEA-Research-2007-083.pdf:3.29MB
Japan Atomic Energy Agency has investigated a sedimentary rock area in the central part of Yoro river basin, in Chiba Prefecture for verification of analytical groundwater flow model. For the purpose of establishing a methodology for evaluation of regional groundwater flow system, investigations of flow rates, chemical compositions and isotope ratios for water samples collected from wells, rivers and springs were carried out. As a result, considerable amount of ground water which is NaCa-HCO type or evolved Ca-HCO type meteoric origin cultivated at the high permeable sand dominant layer preferentially flows toward its strike direction discharging at the downstream region of river. The evolved Ca-HCO type or Na-HCO type ground water with long residence time was inferred to form different flowpath toward the dipping direction of bedrock more than 100m at depth and to upwell to the downstream region of Urajiro River as a feeder of Yoro River through the low permeable mud layer.
Sakai, Ryutaro; Munakata, Masahiro; Kimura, Hideo
JAEA-Research 2006-084, 16 Pages, 2007/01
JAEA-Research-2006-084.pdf:1.74MB
Japan Atomic Energy Agency (JAEA) has started to investigate a sedimentary rock area in the Yoro river basin, in Chiba Prefecture. Hydro-chemical conditions of the regional groundwater were discussed based on temperature, chemical compositions, isotopic ratios of hydrogen and oxygen, and the isotopic age of radioactive carbon for water samples collected from wells, rivers and springs in the Yoro river basin. It was found that the groundwater system in this basin consists of types of water: Ca-HCO type water, Na-HCO type water and NaCl type water. The Ca-HCO type water is meteoric water cultivated several thousand years or after, the Na-HCO type water is meteoric water cultivated under cold climates several to twenty thousand years ago. The NaCl type water is fossil brine water formed twenty thousand years ago. It was also observed that the Na-HCO type water upwelled at the surface originates from GL-200m to -400m.
Kimura, Hideo; Sakai, Tomo*
JAERI-Data/Code 2004-001, 32 Pages, 2004/03
JAERI-Data-Code-2004-001.pdf:1.34MB
no abstracts in English
Kimura, Hideo; Sakai, Tomo*
JAERI-Data/Code 2004-008, 41 Pages, 2004/02
JAERI-Data-Code-2004-008.pdf:4.76MB
no abstracts in English
