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Hidaka, Akihide; Nakano, Yoshihiro; Watanabe, Yoko; Arai, Nobuyoshi; Sawada, Makoto; Kanaizuka, Seiichi*; Katogi, Aki; Shimada, Mayuka*; Ishikawa, Tomomi*; Ebine, Masako*; et al.
JAEA-Review 2016-011, 208 Pages, 2016/07
JAEA-Review-2016-011-01.pdf:33.85MBJAEA-Review-2016-011-02.pdf:27.68MB
JAEA has been conducting the Instructor Training Program (ITP) since 1996 under the auspices of MEXT to contribute to human resource development in currently 11 Asian countries in the field of radiation utilization for seeking peaceful use of nuclear energy. ITP consists of Instructor Training Course (ITC), Follow-up Training Course (FTC) and Nuclear Technology Seminars. In the ITP, trainings or seminars relating to technology for nuclear utilization are held in Japan by inviting nuclear related people from Asian countries to Japan and after that, the past trainees are supported during FTC by dispatching Japanese specialists to Asian countries. News Letter is also prepared to provide the broad range of information obtained through the trainings for local people near NPPs in Japan. The present report describes the activities of FY2014 ITP and future challenges for improving ITP more effectively.
Kohashi, Akio; Onoe, Hironori; Yamamoto, Shinya*; Honda, Makoto*; Sakurai, Hideyuki*; Masumoto, Kiyoshi*
JAEA-Research 2015-022, 89 Pages, 2016/03
JAEA-Research-2015-022.pdf:27.85MB
In Japan, high-level radioactive waste (HLW) will be emplaced in a stable host rock formation deeper than 300 meters underground for geological disposal. It is important to understand heterogeneous distribution of hydraulic conductivity from the viewpoints of the safety assessment of geological disposal of HLW and construction of underground facilities. Inverse analysis based on the transient data is an efficient technique for estimating the heterogeneous distribution. In this study, numerical experiments with the adjoint state method and the ensemble Kalman filter were carried out in order to understand effective method for application of these inverse analysis. As a result of this study, the capability of each analysis techniques was shown.
Kameyama, Hideo*; Sakurai, Makoto*; Masuda, Akiyuki*; Fukui, Tomoaki*; Onuki, Kaoru; Kubo, Shinji; Imai, Yoshiyuki
Suiso Enerugi Shisutemu, 37(1), p.3 - 10, 2012/03
The technical present status of hydrogen production process using IS thermochemical cycle was introduced. This process is experimentally investigated in Japan, U.S.A., Germany, France, Italy, India, China and Korea. Japan Atomic Energy Agency succeeded in consecutive hydrogen production as a proof examination. The trend of the research and development about the reactions, separation technology, device materials and the process equipment were reported. Thermochemical ammonia production cycle was also introduced. This new cycle is named ISN cycle which was modified from IS cycle in order to produce ammonia from water and nitrogen.
Yamamoto, Shinya*; Honda, Makoto*; Sakurai, Hideyuki*; Suzuki, Makoto*; Sanada, Hiroyuki; Sugita, Yutaka; Matsui, Hiroya
Proceedings of 14th Annual Conference of the International Association for Mathematical Geosciences (IAMG 2010) (CD-ROM), 12 Pages, 2010/09
The distribution of groundwater properties is important for understanding of the deep underground hydrogeological environments in the design of the HLW disposal facilities. This study proposes a geostatistical system for modeling the chemical properties of groundwater which have a correlation with the resistivity data obtained from widespread and exhaustive survey. The proposed system is consists of two methodologies (resistivity data integration using Simple Kriging with varying local mean (SKlm) and 3D distribution modeling of hydro-chemical properties of groundwater estimated by SKlm algorithm). 2 types of uncertainty are considered: (1) Aleatory uncertainty; (2) Epistemic uncertainty. As a result, the uncertainties of the proposal model have been estimated lower than other traditional model's.
Honda, Makoto*; Yamamoto, Shinya*; Sakurai, Hideyuki*; Suzuki, Makoto*; Sanada, Hiroyuki; Sugita, Yutaka; Matsui, Hiroya
Doboku Gakkai Rombunshu, C, 66(3), p.609 - 624, 2010/08
This paper proposes a geostatistical system for modeling the groundwater properties which have a correlation with the ground resistivity data obtained from widespread and exhaustive electromagnetic survey. That is, the methodology for the integration of resistivity data measured by various methods and the methodology for modeling the groundwater properties using the integrated resistivity data has been developed. The proposed system has also been validated using the data obtained in the surface-based investigations of the Horonobe URL project. Additionally, the quantification of uncertainties in the estimated model has been tried by numerical simulations based on the data. As a result, the uncertainties of the proposal model have been estimated lower than other traditional model's.
Higashijima, Satoru; Sakurai, Shinji; Suzuki, Satoshi; Yokoyama, Kenji; Kashiwa, Yoshitoshi; Masaki, Kei; Shibama, Yusuke; Takechi, Manabu; Shibanuma, Kiyoshi; Sakasai, Akira; et al.
Fusion Engineering and Design, 84(2-6), p.949 - 952, 2009/06
Times Cited Count：9 Percentile：53.00(Nuclear Science & Technology)An upgrading device of JT-60 tokamak with fully superconducting coils (JT-60SA) is constructed under both the Japanese domestic program and the international program "Broader Approach". The maximum heat flux to JT-60SA divertor is estimated to 15 MW/m
for 100 s, and a monoblock-type CFC divertor armor is promising. The JT-60SA armor consists of CFC monoblocks, a cooling CuCrZr screw-tube, and a thin OFHC-Cu buffer layer, and the brazed joints are essential for the armor. Metalization inside CFC monoblock is applied for further improvement, and we confirmed again that the mock-up has heat removal capability in excess of ITER requirement. For optimization of the fabrication method and understanding of the production yield, the mock-ups corresponding to quantity produced in one furnace is also produced, and the half of the mock-ups could remove 15 MW/m as required. This summarizes the recent progress of design and mock-up test results for JT-60SA divertor armor.
Shibama, Yusuke; Sakurai, Shinji; Masaki, Kei; Sukegawa, Atsuhiko; Kaminaga, Atsushi; Sakasai, Akira; Matsukawa, Makoto
Fusion Engineering and Design, 83(10-12), p.1605 - 1609, 2008/12
Times Cited Count：6 Percentile：39.89(Nuclear Science & Technology)The conceptual design of JT-60SA cryostat is summarized. JT-60SA is designed to be a fully superconducting device and assumed deuterium operation, therefore a cryostat is introduced to secure three functions, which are thermal insulation for entire superconducting magnets, bio-shielding, and gravity support for the entire tokamak device. The cryostat is required to cover up the tokamak devices, which are 15 m of total height and 7 m of radius, and to support the total devices weight of 2550 tons. The cryostat consists of vessel body, gravity support and auxiliary facilities, such as 80 K thermal shield and exhaust system. Each of them is outlined with JT-60SA design conditions, and the operational condition of auxiliary system is clarified, especially, capacity of the exhaust system, which is related to the 80 K thermal shield design.
Matsukawa, Makoto; Kikuchi, Mitsuru; Fujii, Tsuneyuki; Fujita, Takaaki; Hayashi, Takao; Higashijima, Satoru; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Ide, Shunsuke; Ishida, Shinichi; et al.
Fusion Engineering and Design, 83(7-9), p.795 - 803, 2008/12
Times Cited Count：17 Percentile：72.53(Nuclear Science & Technology)no abstracts in English
Kawashima, Hisato; Shimizu, Katsuhiro; Takizuka, Tomonori; Asakura, Nobuyuki; Sakurai, Shinji; Matsukawa, Makoto; Fujita, Takaaki
Fusion Engineering and Design, 83(10-12), p.1643 - 1647, 2008/12
Times Cited Count：18 Percentile：74.35(Nuclear Science & Technology)no abstracts in English
Honda, Makoto*; Sakurai, Hideyuki*; Suzuki, Makoto*; Iwasa, Kengo*; Matsui, Hiroya
JAEA-Research 2008-038, 73 Pages, 2008/06
JAEA-Research-2008-038.pdf:18.44MB
The purpose of this study is to develop a geostatistical procedure for modeling on geological environments and to evaluate quantitative relationship between amount of geological information and reliability of the models using data sets obtained in surface-based investigation phase (Phase 1) of the Horonobe Underground Research Laboratory Project. This study is a joint research with Shimizu Corporation carried out in four years from FY2003 to FY2006. In the first three years, by using the data sets obtained by the geological investigations in each FY, three dimensional models of the resistivity, the chemical composition of groundwater and the hydraulic conductivity were built and undated by the geostatistical method developed in this study. The relationship between the amount of information and the reliability of the models were demonstrated as well through comparisons of the models at each step which corresponds to the investigation stage in each FY. In FY2006, as a summary of this study in the final FY, to confirm the validity of the present method, the above three models were compared with models built by a conventional method. Relationship between the procedure of geological survey and the reliability of the models were also studied by newly computing three sets of models based on fictitious investigation plans, their procedures are different form the actual one, and comparing these four models.
Hayashi, Takao; Sakurai, Shinji; Masaki, Kei; Tamai, Hiroshi; Yoshida, Kiyoshi; Matsukawa, Makoto
Journal of Power and Energy Systems (Internet), 2(2), p.522 - 529, 2008/00
The JT-60SA aims to contribute and supplement ITER toward demonstration fusion reactor based on tokamak concept. One of the features of JT-60SA is its high power long pulse heating, causing the large annual neutron fluence. Because the expected dose rate at the vacuum vessel (VV) may exceed 1 mSv/hr after 10 years operation and three month cooling, the human access inside the VV is prohibited. Therefore a remote handling (RH) system is necessary for the maintenance and repair of in-vessel components. A divertor cassette, which is 10 degrees wide in toroidal direction and weighs 500 kg itself due to the limitations of port width and handling weight, can be exchanged by heavy weight manipulator (HWM). The HWM brings the divertor cassette to the front of the other RH port, which is used for supporting the rail and/or carrying in and out equipments. Then another RH device receives and brings out the cassette by a pallet installed from outside the VV.
Fujita, Takaaki; Tamai, Hiroshi; Matsukawa, Makoto; Kurita, Genichi; Bialek, J.*; Aiba, Nobuyuki; Tsuchiya, Katsuhiko; Sakurai, Shinji; Suzuki, Yutaka; Hamamatsu, Kiyotaka; et al.
Nuclear Fusion, 47(11), p.1512 - 1523, 2007/11
Times Cited Count：24 Percentile：63.05(Physics, Fluids & Plasmas)Design of modification of JT-60U, JT-60SA, has been optimized in viewpoint of plasma control, and operation regimes have been evaluated. Upper and lower divertors with different geometry are prepared for flexibility of plasma shape control. The beam lines of negative-ion NBI are shifted downward for off-axis current drive, in order to obtain a weak/reversed shear plasma. The feedback control coils along the port hole in the stabilizing plate are found effective to suppress the resistive wall mode (RWM) and sustain high 
close to the ideal wall limit. The regime of full current drive operation has been extended with upgraded heating and current drive power. Full current drive operation for 100 s with reactor-relevant high values of normalized beta and bootstrap current fraction (
= 2.4 MA, = 4.4, 
= 0.70, 
/
= 0.86, H
= 1.3) is expected in a highly-shaped low-aspect-ratio configuration (
= 2.65). High , high-density ELMy H-mode is also expected.
Sakurai, Shinji; Masaki, Kei; Shibama, Yusuke; Tamai, Hiroshi; Matsukawa, Makoto
Fusion Engineering and Design, 82(15-24), p.1767 - 1773, 2007/10
Times Cited Count：10 Percentile：57.98(Nuclear Science & Technology)The Japanese national project toward DEMO reactor and a satellite tokamak project for ITER in a Broader Approach with Japan and EU collaboration are combined as the JT-60SA (Super Advanced) project. Design of PFC for JT-60SA is widely modified from original national plan due to the increase of plasma heating power and annual neutron yield. Mono-block divertor target aiming at power handling of 15 MW/m should be adopted to an outer divertor, because expected heat flux will exceed 10 MW/m. Since high coolant flow velocity of 10-12 m/s is required to enhance heat transfer and critical heat flux for swirl or screw tube, primary coolant water system is increased from 1300 to 4600 m
/h. Remote handling system similar with ITER blanket manipulator is adopted to maintain plasma-facing components. Divertor cassette has 10 degree width in toroidal direction and weight of 300 kg itself due to the limitation of port width and manipulator.
Sukegawa, Atsuhiko; Sakurai, Shinji; Masaki, Kei; Kizu, Kaname; Tsuchiya, Katsuhiko; Shibama, Yusuke; Hayashi, Takao; Tamai, Hiroshi; Matsukawa, Makoto
Fusion Engineering and Design, 82(15-24), p.2799 - 2804, 2007/10
Times Cited Count：8 Percentile：51.08(Nuclear Science & Technology)The JT-60SA is planned to be utilized in the existing JT-60 experimental building. The annual neutron fluence from the JT-60SA plasma would be increased up to about 130 times as high as the present JT-60U plasma. The radiation shielding structure of vacuum vessel and cryostat is designed so that no effective change is required to the site boundary condition of JT-60 for radiation safety. Neutron and photon transport calculations have been performed using ANISN, DOT3.5. Nuclear heating of the coil and neutron flux through the vacuum vessel was considered to determine the basic structure of the vacuum vessel. The thickness of the structural and shielding materials for the vacuum vessel to be optimized for the nuclear heating of the NbTi superconducting coil has been changed. So, the vacuum vessel is designed to be a double-walled structure made of SS316L. The inner space in the double wall is filled with a 140mm thickness of borated water for cooling and neutron shielding.
Tamai, Hiroshi; Fujita, Takaaki; Kikuchi, Mitsuru; Kizu, Kaname; Kurita, Genichi; Masaki, Kei; Matsukawa, Makoto; Miura, Yukitoshi; Sakurai, Shinji; Sukegawa, Atsuhiko; et al.
Fusion Engineering and Design, 82(5-14), p.541 - 547, 2007/10
Times Cited Count：9 Percentile：54.69(Nuclear Science & Technology)JT-60SA is positioned as the ITER satellite tokamak to conduct research elements to support and supplement ITER towards DEMO under the joint collaboration of Japan and EU. After the discussions in JA-EU Satellite Tokamak Working Group in 2005, the heating power is increased up to 41MW, 100s to ensure the ITER support research. With such increased heating power, the prospective plasma performances are analysed by the equilibrium and transport analysis codes. Operation window of a fully non-inductive current drive is extended to high density region. Simultaneous achievement of high equivalent Q
and high normalised beta is also expected in wide operational margin. Those prospects strongly indicate that JT-60SA is suitable machine to conduct the advanced research orienting to ITER and DEMO.
C heat resistant boron-loaded resin for neutron shieldingMorioka, Atsuhiko; Sakurai, Shinji; Okuno, Koichi*; Sato, Satoshi; Verzirov, Y. M.; Kaminaga, Atsushi; Nishitani, Takeo; Tamai, Hiroshi; Shibama, Yusuke; Yoshida, Shigeru*; et al.
Journal of Nuclear Materials, 367-370(2), p.1085 - 1089, 2007/08
Times Cited Count：25 Percentile：83.26(Materials Science, Multidisciplinary)A 300C heat-resistant neutron shielding material is newly developed, which consists of phenol-based resin with 6 weight-% boron. The neutron shielding performance of the developed resin, examined by the 
Cf neutron source, is almost the same as that of the polyethylene. The neutron shielding characteristic was also estimated by 3D Monte Carlo Code MCNP-4C2 using the continuous energy cross section data sets based on the JENDL-3.2. The calculation result agrees well with the experimental result. To understand the kinds of the outgas from the developed resin in the high temperature region, the mass spectrum of the outgas was measured until 
300C by Thermal Desorption Specroscopy (TDS). The observed mass number was 2, 17, 18, 28, 32, and 44. The number corresponds to hydrogen (H
), ammonia (NH
), water (HO), carbon monoxide (CO), oxygen (O), carbon dioxide (CO), respectively. The main outgas component from the resin at 100150C was NH and HO. The outgas of NH and HO from the resin have been measured, however, the neutron shielding performance of the resin after 200C baking was almost the same as that before baking. The quantitative analysis of the outgas from the resin in the high temperature region was done by the Temperature Programmed Desorption (TPD) / Gas Chromatography and Mass spectrometry (GC/MS). The 13 kinds of organic gases have been observed by the amount of 
g/g at 300C. The neutron shielding performance of the developed resin at 300C was simulated by the 3D analysis. The resonance cross section of the nucleus is broad at the high temperature region by the Doppler effect. The calculation results using 327C library and 20C library are almost same.
Sawada, Makoto; Sakurai, Naoto
Proceedings of International Symposium on Symbiotic Nuclear Power Systems for 21st Century (ISSNP) (CD-ROM), p.275 - 283, 2007/07
The prototype FBR Monju which caused a sodium leak accident in Dec. 1995 is now under remodeling to attain its re-initial criticality in 2008. The success or failure of its safety operation is an important issue which influences development of nuclear fuel cycle. So, a high quality educational training is strongly required in order to assure its future safety operation. Based on the teachings learned from the accident, Monju has revised its educational training structure extensively such as, a new building a framework of educational training, a new open of Monju FBR Training School, a reinforcement of simulator training, etc.. A total of 29 established training courses, based on the mentioned above improvements, have been conducting towards Monju restarting.
Kizu, Kaname; Tsuchiya, Katsuhiko; Ando, Toshinari*; Sborchia, C.*; Masaki, Kei; Sakurai, Shinji; Sukegawa, Atsuhiko; Tamai, Hiroshi; Fujita, Takaaki; Matsukawa, Makoto; et al.
IEEE Transactions on Applied Superconductivity, 17(2), p.1348 - 1352, 2007/06
Times Cited Count：4 Percentile：29.28(Engineering, Electrical & Electronic)no abstracts in English
Hayashi, Takao; Sakurai, Shinji; Masaki, Kei; Tamai, Hiroshi; Yoshida, Kiyoshi; Matsukawa, Makoto
Transactions of the American Nuclear Society, 96(1), P. 783, 2007/06
JT-60SA equipped with fully superconducting magnets is now being designed as a combined project of the Japanese national project toward DEMO reactor and a satellite tokamak project for ITER in a Broader approach with Japan and EU collaboration. Because the expected dose rate at the vacuum vessel (VV) may exceed 1 mSv/hr after 10 years operation and three month cooling, the human access inside the VV is prohibited. This indicates a remote handling (RH) system is necessary for the maintenance and repair of in-vessel components. This study described the RH system of JT-60SA to exchange or repair the in-vessel components such as first wall tiles and divertor modules. First wall armor tiles fully cover the plasma-side surface of the VV to protect from the plasma. Bolted armor tiles, made by graphite or ferritic steel, on a heat-sink can be replaced by LWM in the VV.
Honda, Makoto*; Suzuki, Makoto*; Sakurai, Hideyuki*; Iwasa, Kengo*; Matsui, Hiroya
JAEA-Research 2007-028, 91 Pages, 2007/04
JAEA-Research-2007-028.pdf:17.93MB
The purpose of this study is to develop the geostatistical procedure for modeling geological environments and to evaluate the quantitative relationship between the amount of information and the reliability of the model using the data sets obtained in Phase 1 of the Horonobe Underground Research Laboratory Project. In FY 2006 research, the data obtained from the deep boreholes which were executed in FY 2005 were newly used in addition to the data sets used in the previous study. And the hydrogeological models were built by using the same geostatistical procedure developed in the previous study. The relationship between the amount of information and the reliability of the model was demonstrated as well through a comparison of the models at each step which corresponds to the investigation stage in each FY. Furthermore, in the case of hydro-chemical model, the modeling procedure was applied to each dissolved principal component and their characteristics of distribution were clarified.
