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Harii, Kazuya*; Umeda, Maki; Arisawa, Hiroki*; Hioki, Tomosato*; Sato, Nana; Okayasu, Satoru; Ieda, Junichi
Journal of the Physical Society of Japan, 92(7), p.073701_1 - 073701_4, 2023/07
Times Cited Count:1 Percentile:22.15(Physics, Multidisciplinary)Umeda, Maki; Chudo, Hiroyuki; Imai, Masaki; Sato, Nana; Saito, Eiji
Review of Scientific Instruments, 94(6), p.063906_1 - 063906_8, 2023/06
Times Cited Count:2 Percentile:27.04(Instruments & Instrumentation)Lee, O.*; Yamamoto, Kei; Umeda, Maki; Zollitsch, C. W.*; Elyasi, M.*; Kikkawa, Takashi*; Saito, Eiji; Bauer, G. E. W.*; Kurebayashi, Hidekazu*
Physical Review Letters, 130(4), p.046703_1 - 046703_6, 2023/01
Times Cited Count:19 Percentile:91.49(Physics, Multidisciplinary)Chen, Y.*; Shiomi, Yuki*; Qiu, Z.*; Niizeki, Tomohiko*; Umeda, Maki*; Saito, Eiji
Scientific Reports (Internet), 9, p.19052_1 - 19052_8, 2019/12
Times Cited Count:0 Percentile:0.00(Multidisciplinary Sciences)Umeda, Takahide*; Okamoto, Mitsuo*; Arai, Ryo*; Sato, Yoshihiro*; Kosugi, Ryoji*; Harada, Shinsuke*; Okumura, Hajime*; Makino, Takahiro; Oshima, Takeshi
Materials Science Forum, 778-780, p.414 - 417, 2014/02
Times Cited Count:2 Percentile:70.05(Crystallography)Interface defects of Metal-Oxide-Semiconductors (MOSFETs) fabricated on Carbone (C) face 4H-SiC were investigated by Electrically Detected Magnet Resistance (EDMR). Gate oxide of the MOSFETs was formed by either wet-oxidation and H annealing or dry-oxidation. The values of channel mobility for MOSFETS with wet gate oxide and dry gate oxide are less than 1 and 90 cm
/Vs, respectively. By EDMR measurement under low temperature (less than 20 K), EDMR signals related to C were detected. The peak height of the signals increased with increasing
-ray doses, and the channel mobility decreased. From this result, it is assumed that hydrogen atoms passivating C dangling bonds are released by
-rays and the channel mobility decreases with increasing the C related defects.
Son, N. T.*; Trinh, X. T.*; Lvile, L. S.*; Svensson, B. G.*; Kawahara, Kotaro*; Suda, Jun*; Kimoto, Tsunenobu*; Umeda, Takahide*; Isoya, Junichi*; Makino, Takahiro; et al.
Physical Review Letters, 109(18), p.187603_1 - 187603_5, 2012/11
Times Cited Count:230 Percentile:98.14(Physics, Multidisciplinary)Kawamura, Makoto; Makino, Hitoshi; Sasao, Eiji; Niizato, Tadafumi; Yasue, Kenichi; Asamori, Koichi; Umeda, Koji; Ishimaru, Tsuneari; Osawa, Hideaki; Ebashi, Takeshi; et al.
JAEA-Research 2010-027, 85 Pages, 2010/09
Japan Atomic Energy Agency (JAEA) have developed a formal evaluation method to assess the potential impacts of natural phenomena (earthquakes and faulting; volcanism; uplift, subsidence, denudation and sedimentation; climatic and sea-level changes) on a high level radioactive waste (HLW) disposal system for the purpose of maintenance of evaluation method for potential impacts of natural phenomena within more realistic view. In this report, we developed a framework as a part of the total system performance assessment for two purposes: the first one is quantification of relationship of characteristic of natural phenomena between geological environmental conditions (T-H-M-C-G), and the other one is quantification of relationship of T-H-M-C-G condition between parameters of performance assessment. We tried to apply the framework to all natural phenomena to confirm the effectiveness of the framework. On the other hand, we applied an argument-diagram that was developed one of the methods of the knowledge management to elicit future tasks. As a result, to apply the framework, we could show that information integration could carry out efficiently, and information integration was attained by the common framework by combining information on geohistory and existing information of natural phenomena and geological environmental conditions as modern-analogue. We could show that suitable scenarios might be chosen by information integration. Furthermore, we were able to elicit future tasks to this study by applying the argument-diagram.
Kawamura, Makoto; Yasue, Kenichi; Niizato, Tadafumi; Tokiwa, Tetsuya; Ebashi, Takeshi; Oi, Takao; Makino, Hitoshi; Ishimaru, Tsuneari; Umeda, Koji
Proceedings of 2008 East Asia Forum on Radwaste Management Conference (2008 EAFORM 2nd Conference) (USB Flash Drive), 6 Pages, 2008/10
Japan Atomic Energy Agency (JAEA) had developed a framework to assess the potential impact of natural phenomena (uplift and denudation/climatic and sea-level changes; earthquakes and faulting; volcanism) on a high level radioactive waste (HLW) disposal system as a part of the total system performance assessment. The framework is focused on identifying key T-H-M-C-G (Thermal-Hydrological-Mechanical-Chemical-Geometrical) process associated with potential changes of the geological environment caused by natural phenomena. By using the framework, we could grasp the relationship between characteristic of natural phenomena and geological environmental conditions (T-H-M-C-G) quantitatively, and grasp the relationship between T-H-M-C-G condition and parameters of performance assessment efficiently. In this paper, we tried to develop perturbation scenarios of uplift and denudation by using the framework. As a result, by applying this framework, we could not only grasp the impacts on the geological environmental conditions (T-H-M-C-G) quantitatively, but the excess and deficiency of information resulting from uplift and denudation.
Kawamura, Makoto; Oi, Takao; Niizato, Tadafumi; Yasue, Kenichi; Tokiwa, Tetsuya; Niwa, Masakazu; Shimada, Koji; Kurosawa, Hideki; Asamori, Koichi; Kawachi, Susumu; et al.
JAEA-Research 2008-018, 47 Pages, 2008/03
In this report, we sophisticated the framework as a part of the total system performance assessment for two purposes: the first one is quantification of relationship of characteristic of natural phenomena between geological environmental conditions (THMCG), and the other one is quantification of relationship of THMCG condition between parameters of performance assessment. On the other hand, we applied the sophisticated framework to all natural phenomena. As a result, to apply the sophisticated framework, we could show that information integration could carry out efficiently. Moreover, we have checked that the framework was applicable to all phenomena. Furthermore, we could show that suitable scenarios might be chosen by information integration.
Kawamura, Makoto; Oi, Takao; Makino, Hitoshi; Umeda, Koji; Niizato, Tadafumi; Yasue, Kenichi; Kawachi, Susumu; Ishimaru, Tsuneari; Seo, Toshihiro; Ebina, Takanori*; et al.
JAEA-Review 2006-039, 60 Pages, 2007/01
This report is to outline a 5-year plan of research and development (R&D) for performance assessment of potential effect of natural phenomena on a geological disposal of high-level radioactive waste in JAEA. In each research plan, objectives based on the necessity and the significance of the research plan are clarified in the section of "Objectives and the past progresses", with summarizing the progresses of H12: Project to establish the scientific and technical basis for HLW disposal in Japan (Second Progress Report), and H17: Development and management of the technical knowledge base for the geological disposal of HLW (H17 report). In addition, next five year plan is described in the section.
Kawamura, Makoto; Oi, Takao; Makino, Hitoshi; Umeda, Koji; Niizato, Tadafumi; Ishimaru, Tsuneari; Seo, Toshihiro
Proceedings of 2006 East Asia Forum on Radwaste Management Conference (2006 EAFORM Conference), p.350 - 367, 2006/11
Evaluation for potential impact of natural phenomena ("earthquakes and fault movement", "volcanism", "uplift, subsidence and denudation", and "climatic and sea-level changes") on a High-Level radioactive Waste (HLW) disposal system is an important issue in safety assessment. In order to develop the perturbation scenario considering diverse and complex impact of natural phenomena comprehensively, it is important to identify the key factors to easily classify and organize these impacts and relate these factors with the system performance. In this method, a series of work to construct scenarios is divided into pieces to facilitate to elicit the features of potential impact of natural phenomena on a HLW disposal system and is organized to create reasonable scenarios with consistency, traceability and adequate conservativeness within realistic view.
Kawamura, Makoto; Makino, Hitoshi; Umeda, Koji; Seo, Toshihiro; Ishimaru, Tsuneari; Osawa, Hideaki
Saikuru Kiko Giho, (28), p.53 - 64, 2005/09
Evaluation for potential effect of natural phenomena on a HLW disposal system is an important issue in safety assessment. A scenario construction method for the effects on a HLW disposal system condition and performance has been developed for two purposes, first one is effective elicitation and organization of information from investigators of natural phenomena and performance assessor, the other is maintenance of traceability of scenario construction processes with suitable records. In this method, a series of works to construct scenarios is divided into pieces to facilitate to elicit the features of potential effect of natural phenomena on a HLW disposal system and is organized to create reasonable scenarios with consistency, traceability and adequate conservativeness within realistic view.
Fujine, Sachio; Murata, Mikio; Abe, Hitoshi; Takada, Junichi; Tsukamoto, Michio; Miyata, Teijiro*; Ida, Masaaki*; Watanabe, Makio; Uchiyama, Gunzo; Asakura, Toshihide; et al.
JAERI-Research 99-056, p.278 - 0, 1999/09
no abstracts in English
Kawamura, Makoto; Umeda, Koji; Oi, Takao; Ishimaru, Tsuneari; Niizato, Tadafumi; Yasue, Kenichi; Makino, Hitoshi
no journal, ,
Murakami, Makoto*; Kawamura, Makoto; Sasaki, Hisashi*; Makino, Hitoshi; Seo, Toshihiro; Nishimura, Takuya*; Umeda, Koji; Oi, Takao; Geshi, Nobuo*; Oikawa, Teruki*
no journal, ,
The volcanic scenario has mainly been conventionally examined from a viewpoint of empiricism based on the understanding of physics and/or scientific mechanism of volcanic activity. However, when a volcanic scenario is examined only based on the empiricism of a volcano, there is a possibility that the phenomena which the volcano had not experienced in the past may fall out from the scenario. Therefore, it is necessary to follow up omission by collecting information from various volcanoes. The purpose of this research is to develop the scenario analysis technique which can perform prediction of progress of volcanic activity by applying the FEP analysis technique examined by High level radioactive waste geological disposal. As a result, a volcanic scenario can be built by applying the FEP analysis technique. It was understood that the FEP analysis technique developed by geological isolation can apply also to the field of other technology. We will collect information further and apply this technique to other volcanoes. We consider improvement of the FEP analysis technique based on the result of this study.
Murakami, Makoto*; Kawamura, Makoto*; Makino, Hitoshi; Geshi, Nobuo*; Oikawa, Teruki*; Nishimura, Takuya*; Umeda, Koji; Sasaki, Hisashi*; Seo, Toshihiro; Oi, Takao*
no journal, ,
The prediction technique of the volcanism is requested from the viewpoint of disaster prevention now. The prediction method using the volcanic scenario has been paid to attention. The purpose of this study is to develop the methodology of the volcanic scenario construction that the progress of the volcanic activity is predictable by progressively applying the FEP analysis methodology in the research of HLW geological disposal to the volcanic activity. A basic concept is as follows. We resolve the phenomena to compose the volcanic activity to the single-process referring to past volcanic eruptions. The single-process is arranged to the logical function theory. And, the development of volcanic scenarios is expressed as a chain of the functions. As a result, we developed adaptable volcano scenarios to the purpose. Moreover, it could be expected that the observations are made more effective by feeding back this methodology to the field survey.
Umeda, Takahide*; Sato, Yoshihiro*; Arai, Ryo*; Okamoto, Mitsuo*; Harada, Shinsuke*; Kosugi, Ryoji*; Okumura, Hajime*; Makino, Takahiro; Oshima, Takeshi
no journal, ,
no abstracts in English
Ishimaru, Tsuneari; Shimada, Koji; Niwa, Masakazu; Yasue, Kenichi; Tateishi, Ryo*; Ikeda, Makinori; Umeda, Koji
no journal, ,
no abstracts in English
Ishimaru, Tsuneari; Shimada, Koji; Sasaki, Akimichi; Tanaka, Yukumo; Miyazaki, Masashi; Yasue, Kenichi; Niwa, Masakazu; Sueoka, Shigeru; Umeda, Koji; Ikeda, Makinori
no journal, ,
The Nuclear Regulation Authority instructed to develop a further additional research plan regarding the crushed zones on the Monju site against the JAEA on September 25. The JAEA developed a research plan in response to this instruction, and, the stripping investigation with expansion of the area, the additional detailed geographical and geological surveys around the mountains/terrace boundary, and the marine seismic surveys in the coastal waters, were conducted. The fracture zones were grouped into 2 systems called -system and
-system in the on-site investigation. We examined the cross-cutting relationships and displacements of the fracture zones and confirmed that the
-system was formed after the
-system. From the investigation results so far, similar to the results of the compilation report of April 31, 2010, no clear evidence was observed to support that on-site crushed zones are active faults.
Shimada, Koji; Tateishi, Ryo*; Ishimaru, Tsuneari; Sasaki, Akimichi; Tanaka, Yukumo; Miyazaki, Masashi; Yasue, Kenichi; Niwa, Masakazu; Sueoka, Shigeru; Umeda, Koji; et al.
no journal, ,
Activity evaluation of crush zones encountered in basement rock is an issue of the seismic safety assessment of nuclear plant and geological isolation of radioactive wastes. The selection of crush zone of which has been evaluated should be defined as the latest one by means of turn determination of crush zone activity based on stratigraphic or structural geological method. A lesson from granitic basement rock (Kojaku granite) holding the fast breeder reactor "Monju" is presented. The Kojaku Granite form the oval Tsuruga peninsula (ca. 8km in width) on the southeastern coast of the Sea of Japan and the age is 68.5 plus/minus 0.7Ma (Zircon U-Pb age).1. Stratigraphy-oriented turn determination of crush zone activity. (1.1) Turn determination using cover sediments. (1.2) Turn determination using dyke, mineral and clay vein. 2. Structural-oriented turn determination of crush zone activity.