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Collaborative Laboratories for Advanced Decommissioning Science; Okayama University*
JAEA-Review 2023-038, 48 Pages, 2024/03
JAEA-Review-2023-038.pdf:2.58MB
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2022. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2022, this report summarizes the research results of the "Embedded system using a radiation-hardened processor" conducted in FY2022. The present study aims to be developing a radiation-hardened optoelectronic processor with a 10 MGy total-ionizing-dose (TID) tolerance, a radiation-hardened processor without any optical component with a 4 MGy TID tolerance, a radiation-hardened memory with a 4 MGy TID tolerance, and a radiation-hardened power supply unit with a 1 MGy TID tolerance. Moreover, Japanese research group will support radiation- hardened field programmable gate arrays, power supply units, and radiation-hardened optical systems for radiation-hardened robot systems and radiation sensor systems developed by UK team.
Nuclear Human Resource Development Center
JAEA-Review 2023-034, 67 Pages, 2024/01
JAEA-Review-2023-034.pdf:2.32MB
This annual report summarizes the activities of Nuclear Human Resource Development Center (NuHRDeC) of Japan Atomic Energy Agency (JAEA) in the fiscal year (FY) 2022. In FY 2022, in addition to the regular training programs at NuHRDeC, we actively organized special training courses responding to the external training needs, cooperated with universities, offered international training courses for Asian countries and promoted activities of the Japan Nuclear Human Resource Development Network (JN-HRD.net). In FY2022, we were able to implement face-to-face training, etc., after thoroughly implementing measures to prevent the spread of the new coronavirus infection. Regular domestic training programs; training courses for radioisotopes and radiation engineers, nuclear energy engineers and national qualification examinations, were conducted as scheduled in the annual plan. We also delivered training for the Japan Atomic Power Company and other organizations outside the JAEA. We continued cooperative activities with universities, such as acceptance of postdoctoral researchers, and activities in line with the cooperative graduate school system, including the acceptance of students from Nuclear Professional School, the University of Tokyo. Furthermore, joint course among seven universities was successfully held by utilizing remote education system. The joint course and the intensive summer course and nuclear fuel cycle training were conducted as part of the collaboration network with universities. The Instructor Training Program (ITP) under the contract with Ministry of Education, Culture, Sports, Science and Technology, was continually offered to the ITP participating countries. As part of the ITP, the Instructor Training courses such as "Reactor Engineering Course", advanced instructor training course, and the nuclear technology seminar "Basic Radiation Knowledge for School Education" were conducted face-to-face at NuHRDeC.
Nakayama, Masashi
JAEA-Review 2023-019, 70 Pages, 2023/11
JAEA-Review-2023-019.pdf:6.83MB
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant technologies for geological disposal of high-level radioactive waste through investigating the deep geological environment within the host sedimentary rocks at Horonobe Town in Hokkaido, north Japan. In the fiscal year 2023, we continue R&D on "Study on near-field system performance in geological environment", "Demonstration of repository design options", and "Understanding of buffering behaviour of sedimentary rocks to natural perturbations". These are identified as key R&D challenges to be tackled in the Horonobe underground research plan for the fiscal year 2020 onwards. In the "Study on near-field system performance in geological environment", we conduct the coupled analysis on the full-scale engineered barrier system performance experiment and test the coupled simulation code through comparison with different simulation codes in the international DECOVALEX-2023 collaboration project. Borehole investigations are also carried out for solute transport experiments in the Koetoi Formation. As for "Demonstration of repository design concept", we carry out in situ experiments and data analysis on concrete deterioration under the subsurface conditions. Geophysical surveys are also carried out around an experimental tunnel to be newly excavated at the 350m gallery and characterise the initial conditions of the excavation damaged zone. For the "Understanding of buffering behaviour of sedimentary rocks to natural perturbations", we analyse the results of the hydraulic disturbance tests conducted in previous years and understand the relationship between rock stress / stress state and fault / fracture hydraulic connectivity. Concerning the construction and maintenance of the subsurface facilities, the 350 m gallery is extended and shafts are sank to a depth of 500 m.
Nakayama, Masashi
JAEA-Review 2022-026, 66 Pages, 2022/11
JAEA-Review-2022-026.pdf:12.31MB
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies for geological disposal of High-level Radioactive Waste through investigations of the deep geological environment within the host sedimentary rock at Horonobe Town in Hokkaido, north Japan. In fiscal year 2022, we continue to conduct research on "Study on near-field system performance in geological environment", "Demonstration of repository design options", and "Understanding of buffering behaviour of sedimentary rocks to natural perturbations", which are the important issues shown in the Horonobe underground research plan from fiscal year 2020. The main studies to be conducted in fiscal year 2022 are as follows. As "Study on near-field system performance in geological environment", we will continue to the test under the simulated condition in which the heat generation by the high-level radioactive waste has subsides in the full-scale engineered barrier system (EBS) performance experiment. We will also conduct solute transport experiment with model testing that take into account the effects of organic matter, microbes, and colloids, and initiate borehole investigation to evaluate solute transport experiments on fractures distribute in Koetoi formation. As "Demonstration of repository design concept", we will continue experiment and analysis of concrete deterioration in the underground environment as a demonstration of remote technique for emplacement and retrievable. As a demonstration of the closure techniques, laboratory tests will be continued to investigate the mechanism of bentonite runoff behaviour, which could be a factor in changing the performance of backfill material, and to expand data on swelling and deformation behaviour. In addition, in-situ borehole closure tests will be conducted to evaluate the applicability of the closure method. As "Understanding of buffering behaviour of
Collaborative Laboratories for Advanced Decommissioning Science; Okayama University*
JAEA-Review 2022-017, 56 Pages, 2022/08
JAEA-Review-2022-017.pdf:6.39MB
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Radiation tolerant rapid criticality monitoring with radiation-hardened FPGAs" conducted in FY2020. This research is developing a radiation-hardened optoelectronic FPGA with a 1 Grad total-ionizing-dose tolerance on which optical technologies are introduced onto a semiconductor technology and a radiation hardened FPGA with a 200 Mrad total-ionizing-dose tolerance not using any optical component. Moreover, Japanese research group will support hardware acceleration on FPGAs used for neutron-detection system developed by UK team.
Kitamura, Akira
JAEA-Data/Code 2020-020, 164 Pages, 2021/03
JAEA-Data-Code-2020-020.pdf:3.11MB
JAEA-Data-Code-2020-020-appendix(DVD-ROM).zip:0.56MB
Part of JAEA's Thermodynamic Database (JAEA-TDB) for solubility and speciation of radionuclides (JAEA-TDB-RN) for performance assessment of geological disposal of high-level radioactive and TRU wastes has been updated with subsuming the database for geochemical calculations (JAEA-TDB-GC). This report has focused to update JAEA-TDB-RN after selecting change in standard Gibbs free energy of formation (
), change in standard enthalpy change of formation (
), standard molar entropy (
) and, heat capacity (
), change in standard Gibbs free energy of reaction (
), change in standard enthalpy change of reaction (
) and standard entropy change of reaction (
) as well as logarithm of equilibrium constant (log
) at standard state. The extent of selection of these thermodynamic data enables to evaluate solubility and speciation of radionuclides at temperatures other than 298.15 K. Furthermore, the latest thermodynamic data for iron which have been critically reviewed, selected and compiled by the Nuclear Energy Agency within Organisation for Economic Co-operation and Development (OECD/NEA) have been accepted. Most of previously selected log have been refined to confirm internal consistency with JAEA-TDB-GC. Text files of the updated JAEA-TDB have been provided for geochemical calculation programs of PHREEQC and Geochemist's Workbench.
Collaborative Laboratories for Advanced Decommissioning Science; Shizuoka University*
JAEA-Review 2020-059, 42 Pages, 2021/01
JAEA-Review-2020-059.pdf:3.07MB
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2019. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Radiation tolerant rapid criticality monitoring with radiation-hardened FPGAs". This research is developing a radiation-hardened optoelectronic FPGA with a 1 Grad total-ionizing-dose tolerance on which optical technologies are introduced onto a semiconductor technology and a radiation hardened FPGA with a 200 Mrad total-ionizing-dose tolerance not using any optical component. Moreover, Japanese research group will support hardware acceleration on FPGAs used for neutron-detection system developed by UK team. Finally, we will provide our radiation-hardened FPGA for the UK neutron-detection system.
Sono, Hiroki; Sukegawa, Kazuhiro; Nomura, Norio; Okuda, Eiichi; Study Team on Safety and Maintenance; Study Team on Quality Management; Task Force on New Nuclear Regulatory Inspection Systems
JAEA-Technology 2020-013, 460 Pages, 2020/11
JAEA-Technology-2020-013.pdf:13.46MB
Japan Atomic Energy Agency (JAEA) has completed the introduction of a new frame work of safety, maintenance and quality management activities under the new acts on the Regulation of nuclear source material, nuclear fuel material and reactors since April 2020, in consideration of variety, specialty and similarity of nuclear facilities of JAEA (Power reactor in the research and development stage, Reprocessing facility, Fabrication facility, Waste treatment facility, Waste burial facility, Research reactor and Nuclear fuel material usage facility). The JAEA task forces on new nuclear regulatory inspection systems prepared new guidelines on (1) Safety and maintenance, (2) Independent inspection, (3) Welding inspection, (4) Free-access response, (5) Performance indicators and (6) Corrective action program for the JAEA's nuclear facilities. New Quality management systems and new Safety regulations were also prepared as a typical pattern of these facilities. JAEA will steadily improve these guidelines, quality management systems and safety regulations, reviewing the official activities under the new regulatory inspection system together with the Nuclear Regulation Authority and other nuclear operators.
Nakamura, Hironobu; Kimura, Takashi; Yamazaki, Katsuyuki; Kitao, Takahiko; Tasaki, Takashi; Iida, Toru
Proceedings of International Conference on Physical Protection of Nuclear Material and Nuclear Facilities (Internet), 9 Pages, 2018/09
After the accident of Fukushima Daiichi Nuclear Power Station, to develop effective security measures based on the lesson learned from such crisis and to meet the IAEA Nuclear Security Recommendations (INFCIRC/225/Rev.5), NRA in Japan made a partial amendment of the regulations concerning the reprocessing activity in 2012. The Tokai reprocessing facility implemented all of those security measures by the end of March 2014. Those new measures help us to keep high degree of security level and contributed to our planned operations to reduce the potential risk of the plant. On the other hand, the trustworthiness program was newly introduced in 2016, based on the trustworthiness policy determined by NRA. The implementing entity of the program is JAEA for the Tokai Reprocessing Facility and is required for both the persons afford unescorted access to Category I and II, CAS/SAS, and the persons afford access to the sensitive information. Those who are involved this program will be judged before engaging the work whether they might act as insider to cause or assist radiological sabotage or unauthorized removal of nuclear material, or leak sensitive information. The program is expected as a measure against insider at reprocessing facilities, and is expected to be enforced around the autumn of 2017. As well as the establishment of security measures, the promoting nuclear security culture for all employees was a big challenge. The Tokai reprocessing facility have introduced several security culture activities, such as case study education of security events done by a small group and putting up the security culture poster and so on. This paper presents introduction and implementation with effectiveness of security measures in the Tokai reprocessing facilities and the future security measures applied to the reprocessing facilities are discussed.
Nakamura, Hironobu; Kitao, Takahiko; Yamada, Hiroyuki; Kono, Soma; Kimura, Takashi; Tasaki, Takashi
Proceedings of INMM 59th Annual Meeting (Internet), 9 Pages, 2018/07
Kai, Tetsuya; Hiroi, Kosuke; Su, Y. H.; Shinohara, Takenao; Parker, J. D.*; Matsumoto, Yoshihiro*; Hayashida, Hirotoshi*; Segawa, Mariko; Nakatani, Takeshi; Oikawa, Kenichi; et al.
Physics Procedia, 88, p.306 - 313, 2017/06
Times Cited Count：4 Percentile：84.9(Instruments & Instrumentation)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.
Okamoto, Tsutomu; Minato, Futoshi; Koura, Hiroyuki; Iwamoto, Osamu
JAEA-Data/Code 2015-029, 30 Pages, 2016/03
JAEA-Data-Code-2015-029.pdf:1.81MB
The booklet "chart of the nuclides" is issued every 4 years since 1976 from Nuclear Data Center, JAEA. The chart of the nuclides for WWW (World Wide Web) was developed in 1999 in order to be available from internet browser. Internet connection speeds, browser functions and JavaScript libraries has, however, progressed at present compared with the internet technology in those days. In connection with the release of the 2014 edition of the chart of the nuclides, the interface of the WWW chart of the nuclides has been improved by introducing new internet technologies aiming at enhancing convenience on accessibilities via browsers. We introduced a scrolling screen that would make capabilities of easy screen movement on a map with the addition of the drag scrolling function. Considering smart phone access, the light-weight edition which introduced automatic switch was prepared. The new system results in reduction in access time and usefulness in mobile environment. The method of making figures of the chart was reconsidered due to addition of new decay schemes to the 2014 edition. SVG (Scalable Vector Graphics) was adopted so as to make figures easily. It is concluded that the accessibilities of WWW chart of the nuclides are substantially improved from the previous version by introducing the new technologies.
Hidaka, Akihide; Nakamura, Kazuyuki; Watanabe, Yoko; Yabuuchi, Yukiko; Arai, Nobuyoshi; Sawada, Makoto; Yamashita, Kiyonobu; Sawai, Tomotsugu; Murakami, Hiroyuki
Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 9 Pages, 2015/05
Kudo, Tamotsu; Hidaka, Akihide*; Fuketa, Toyoshi
Proceedings of 2005 Water Reactor Fuel Performance Meeting (CD-ROM), p.883 - 889, 2005/10
The VEGA program have been performed at Japan Atomic Energy Research Institute (JAERI). The program was comprised of series of experiments on radionuclides release from fuel under severe accident conditions and post-test evaluation with numerical calculations. Effects on the release of ambient pressure, fuel temperature, inert or steam environment and MOX-effect were studied in the program. These effects had been hardly investigated in previous studies due to difficulties in experiments with high temperature and pressure conditions. Release of cesium was mitigated at elevated pressure in comparison with atmospheric pressure. Cesium release was enhanced in the temperature region where fuel foaming occurred below the melting point of UO
. Release of cesium and ruthenium under steam condition was greater than that under the inert helium condition. Released mass of plutonium above 2800 K was higher by nearly three orders of magnitude than that in lower temperature than 2800 K.
Hidaka, Akihide; Kudo, Tamotsu; Ishikawa, Jun; Fuketa, Toyoshi
Journal of Nuclear Science and Technology, 42(5), p.451 - 461, 2005/05
Times Cited Count：6 Percentile：40.41(Nuclear Science & Technology)The radionuclide release from MOX under severe accident conditions was investigated in VEGA program to contribute to the technical bases for safety evaluation including PSA for LWR using MOX. The MOX specimens irradiated at ATR Fugen were heated up to 3123K in helium at 0.1 and 1.0MPa. The release of volatile FP was slightly enhanced below 2200K compared with that of UO. The volatile FP release at elevated pressure was decreased as in the case with UO. The total fractional release of Cs reached almost 100% while almost no release of low-volatile FP even after the fuel melting. The release rate of plutonium above 2800K increased rapidly although the amount was small. Since the existing models cannot predict this increase, an empirical model was prepared based on the data. There is no large difference in FP inventories between UO and MOX, and the fractional releases from MOX can be mostly predicted by the model for UO. This suggests that the consequences of LWR using MOX are mostly equal to those using UO from a view point of risks.
Nakagome, Yoshihiro*; Shimizu, Kenichi
Kaku Busshitsu Kanri Senta Nyusu, 34(2), p.14 - 19, 2005/02
RERTR(Reduced Enrichment for Research and Test Reactors) for 2004 was held at IAEA in Vienna of Austria, An author and Professor Nakagome(Kyoto University) attended this internationalmeeting and the author presented "Status of Reduced Enrichment Program for Research Reactors in Japan" with Dr.Nakagome. JNMCC(Japan Nuclear Material Control Center) requested to present a report of 2004 RERTR international Meeting and related content for the author and Dr.Nakagome. the content of the report described the meeting content and related issue which related US FRR SNF(Foregin Reserach Reactors Spent Nuclear Fuels) Acceptance Program.
Hidaka, Akihide; Kudo, Tamotsu; Fuketa, Toyoshi
Transactions of the American Nuclear Society, 91, p.499 - 500, 2004/12
The radionuclides release from MOX under severe accident conditions was investigated in the VEGA program to prepare the technical bases for safety evaluation including PSA for LWR using MOX. The MOX specimen irradiated at ATR Fugen was heated up to 3123K in He at 0.1MPa. The Cs release started at about 1000K and was enhanced below 2200K compared with that of UO. The possible reason is due to the formation of cracks connected to the high burn-up Pu spots. The total fractional releases were evaluated by alpha-ray, gamma-ray and ICP-AES and compared with the ORNL-Booth model. Although the model was prepared based on the tests with UO, the predictions are in reasonable agreement with the measurements. The VEGA test showed that the total releases from MOX are almost the same as those from UO under extremely severe accident conditions. This indicates that the consequences of LWR using MOX are mostly equal to those using UO. The effect of difference between MOX and UO on the consequences will be systematically investigated using the JAERI's source term code, THALES-2.
Miyamoto, Yukihiro; Sakamaki, Tsuyoshi*; Maekawa, Osamu*; Nakashima, Hiroshi
JAERI-Tech 2004-054, 72 Pages, 2004/08
A standard is provided for the radiation monitor based on LAN (Local Area Network) and PLC (Programmable Logic Controller) technology at the introduction to the Japan Proton Accelerator Research Complex (J-PARC). The monitor consists of radiation measurement equipments and the central monitoring panel. The formers are installed in the radiation field, and the latter is installed in the control room and composed of PLC, which are connected with LAN. Extension of the existing standard and the conformity to the international standard were thought as important in providing the standard. The standard is expected to improve the compatibility, maintenancability and productivity of the components.
Onizawa, Kunio; Suzuki, Masahide
JSME International Journal, Series A, 47(3), p.479 - 485, 2004/07
In the structural integrity assessment of reactor pressure vessel, fracture toughness values are estimated by assuming that the radiation effect on fracture toughness is equivalent to that on Charpy properties. Therefore, it is necessary to establish the correlation between both properties especially on irradiation embrittlement. In this paper, we present the fracture toughness data obtained by applying the master curve approach that was adopted recently in the ASTM test method. Materials used in this study are five ASTM A533B class 1 steels and one weld metal. Neutron irradiation for Charpy-size specimens as well as standard Charpy-v specimens was carried out at the Japan Materials Testing Reactor. The shifts of the reference temperature on fracture toughness due to neutron irradiation are evaluated. Correlation between the fracture toughness reference temperature and Charpy transition temperature is established. Based on the correlation, the optimum test temperature for fracture toughness testing and the method to determine a lower bound fracture toughness curve are discussed.
