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Terada, Hiroaki
Ten Hasseigen Karano Mesosukeru Kakusan Shumireshon; Fukushima Daiichi Genshiryoku Hatsudensho Jiko O Fumaete (Kisho Kenkyu Noto Dai-248-Go), p.115 - 121, 2023/09
no abstracts in English
Nagai, Haruyasu; Chino, Masamichi*
Ten Hasseigen Karano Mesosukeru Kakusan Shumireshon; Fukushima Daiichi Genshiryoku Hatsudensho Jiko O Fumaete (Kisho Kenkyu Noto Dai-248-Go), p.1 - 58, 2023/09
no abstracts in English
Shimada, Kazumasa; Nagai, Haruyasu; Hashimoto, Makoto; Iimoto, Takeshi*
Nihon Genshiryoku Gakkai-Shi ATOMO
, 65(5), P. 290, 2023/05
This article is part of the special feature article "What should be done from now on after the 1F accident and what should be conveyed to the next generation after the 1F accident?" of the Atomic Energy Society of Japan, which summarizes the discussions and future proposals on nuclear disaster prevention in which the members of the Health Physics and Environment Science Subcommittee have been involved. In view of the recommendations of the Accident Investigation Committee of the Atomic Energy Society of Japan and the Meteorological Society of Japan, the behavior of radioactive plumes and the prediction of residents' evacuation behavior should be studied to support decision-making on evacuation and other protective measures for residents in and outside the UPZ. Furthermore, decision-making on protective measures and practical risk communication to residents based on radiation health risks to residents and ethical aspects are newly proposed.
Suzuki, Gen*; Ishikawa, Tetsuo*; Oba, Takashi*; Hasegawa, Arifumi*; Nagai, Haruyasu; Miyatake, Hirokazu*; Yoshizawa, Nobuaki*
Journal of Radiation Research (Internet), 63(6), p.796 - 804, 2022/11
Times Cited Count：2 Percentile：27.14(Biology)To elucidate the association between radiation dose and thyroid cancer after the 2011 Fukushima Daiichi Nuclear Power Station (FDNPS) accident, it is essential to estimate individual thyroid equivalent doses (TEDs) to children. In a previous study, we reported a methodology for reconstructing TEDs from inhalation based on individual behavioural survey sheets combined with a spatiotemporal radionuclides database constructed by an atmospheric transport, diffusion, and deposition model (ATDM). In the present study, we further refined our methodology and estimated the combined TEDs from inhalation and ingestion among children in 16 municipalities around the nuclear power station utilizing 3,256 individual whereabouts questionnaire survey sheets. Distributions of estimated TEDs were similar to estimates based on direct thyroid measurements in 1080 children in Iwaki City, Kawamata Town, Iitate Village, and Minamisoma City. Mean TEDs in 1-year-old children ranged from 1.3 mSv in Date City to 14.9 mSv in Odaka Ward in Minamisoma City, and the 95th percentiles varied from 2.3 mSv in Date City to 28.8 mSv in Namie Town. In the future, this methodology can be useful for a case-control study of thyroid cancer after the FDNPS accident.
Moriguchi, Yuichi*; Sato, Yosuke*; Morino, Yu*; Goto, Daisuke*; Sekiyama, Tsuyoshi*; Terada, Hiroaki; Takigawa, Masayuki*; Tsuruta, Haruo*; Yamazawa, Hiromi*
KEK Proceedings 2021-2, p.21 - 27, 2021/12
no abstracts in English
Nemoto, Miho*; Ebine, Noriya; Okamoto, Akiko; Hosaka, Yasuhisa*; Tsuzuki, Katsunori; Terada, Hiroaki; Hayakawa, Tsuyoshi; Togawa, Orihiko
JAEA-Technology 2021-013, 41 Pages, 2021/08
JAEA-Technology-2021-013.pdf:2.52MB
When North Korea has carried out nuclear tests, Nuclear Emergency Assistance and Training Center (NEAT) predicts atmospheric dispersion of radionuclides by using the WSPEEDI-II upon requests from Nuclear Regulation Authority (NRA) and submits the predicted results to NRA in cooperation with Nuclear Science and Engineering Center (NSEC). This is a part of the activity of NEAT supporting the Japanese Government in emergency responses. The WSPEEDI-II automatic calculation system specialized for responses to nuclear tests by North Korea was developed by NSEC and was used for responses to three nuclear tests from February 2013 to September 2017. This report describes the transfer and installation of the calculation system to NEAT, and the subsequent maintenance and operation. Future issues for responses to nuclear tests are also described in this report.
Terada, Hiroaki; Nagai, Haruyasu
Isotope News, (775), p.44 - 48, 2021/06
no abstracts in English
Nagai, Haruyasu
Fission Product Behavior under Severe Accident, p.112 - 116, 2021/05
no abstracts in English
Ishizaki, Shuhei; Hayakawa, Tsuyoshi; Tsuzuki, Katsunori; Terada, Hiroaki; Togawa, Orihiko
JAEA-Technology 2018-007, 43 Pages, 2018/10
JAEA-Technology-2018-007.pdf:5.67MB
When North Korea has carried out a nuclear test, by a request from Nuclear Regulation Authority (NRA), Nuclear Emergency Assistance and Training Center (NEAT) predicts atmospheric dispersion of radionuclides by WSPEEDI-II system in cooperation with Nuclear Science and Engineering Center (NSEC), and submits the predicted results to NRA as the activity to assist responses by the Japanese Government. This report explains frameworks of the Japanese Government and Japan Atomic Energy Agency (JAEA) to cope with nuclear tests by North Korea, and describes a series of activities by NEAT regarding predictions of atmospheric dispersion of radionuclides in response to the 5th and 6th nuclear tests carried out by North Korea in September 2016 and September 2017. Future plans and issues to be solved for responses to nuclear tests are also described in this report, together with an outline of a computer program system used in the predictions.
Nakayama, Hiromasa; Takemi, Tetsuya*
Proceedings of 18th International Conference on Harmonisation within Atmospheric Dispersion Modelling for Regulatory Purposes (HARMO-18) (USB Flash Drive), p.843 - 847, 2017/10
We have attempted to develop a practical and quick local-scale atmospheric dispersion calculation method using an overlapping technique for plume concentration distributions in an emergency response to nuclear accidents. In order to evaluate the overlapping approach, we performed LESs of turbulent flows and plume dispersion under varying mean wind directions using the meteorological data as the model input. When compared with the simulated results under the real meteorological condition, it is shown that the concentration distribution patterns are reasonably simulated by the overlapping method. It can be concluded that the atmospheric dispersion calculation method using the overlapping technique has potential performance for emergency responses to nuclear accidents.
Nishimura, Tomohiro; Onuma, Toshimitsu*; Mizutani, Tomoko; Nakano, Masanao
JAEA-Technology 2017-019, 60 Pages, 2017/09
JAEA-Technology-2017-019.pdf:3.2MB
The meteorological observation has been performed since 1969's in the Nuclear Fuel Cycle Engineering Laboratories, JAEA after 1974. The meteorological observation data has been applied for the calculation of the atmospheric diffusion of radioactive wastes since the hot run was started 1977. This report presents statistical results of meteorological observation based on the decadal data from fiscal year 2005 to 2015. The characteristics of atmospheric diffusion related to the meteorological parameter are also discussed in this report.
C accumulated in vegetation around a nuclear facility; Application of a sophisticated land surface C model to the Rokkasho reprocessing plant, JapanOta, Masakazu; Katata, Genki; Nagai, Haruyasu; Terada, Hiroaki
Journal of Environmental Radioactivity, 162-163, p.189 - 204, 2016/10
Times Cited Count：7 Percentile：22.36(Environmental Sciences)Impacts of plant C uptake on (C) distributions around a nuclear facility were investigated by a land surface C model (SOLVEG-II). The simulation combined the SOLVEG-II with a mesoscale model and an dispersion model was applied to CO
transfer at test operations of the Rokkasho reprocessing plant (RRP) in 2007. The calculated C-specific activities in rice grains agreed with the observations. Numerical experiment of chronic CO release from the RRP showed that C-specific activities of rice plants at harvest differed from the annual mean ones in the air, which was attributed to seasonal variations in atmospheric CO and plant growth. C accumulation in plant significantly increased when CO releases were limited during daytime, compared with the results observed during nighttime, due to extensive CO uptake by daytime photosynthesis. These results indicated that plant growth and photosynthesis should be considered in predictions of ingestion dose of C for long-term chronic and short-term diurnal releases of CO, respectively.
Nagai, Haruyasu; Terada, Hiroaki; Chino, Masamichi; Katata, Genki; Mikami, Satoshi; Saito, Kimiaki
Proceedings of 16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-16) (USB Flash Drive), p.4044 - 4052, 2015/08
JAEA has estimated the atmospheric releases of radionuclide during the Fukushima Daiichi Nuclear Power Station (FNPS1) accident by comparing measurements of air concentration of a radionuclide or its dose rate in the environment with the ones calculated by atmospheric transport and deposition model (ATDM). To improve our source term, we are trying to develop more sophisticated estimation method and use new information from severe accident analysis and observation data. As the first step of new trial, we used 
Cs/
Cs ratios of inventories in FNPS1 reactors Unit 1 to 3 and those in surface deposition. By considering temporal change in Cs/Cs ratio of released plume and ATDM simulations, spatial distribution of Cs/Cs ratio in surface deposition was explained. This result can be used to specify from which reactor the dominant release occurred for each time period, and consequently provide useful information to severe accident analysis for the FNPS1 case.
Hayashi, Takashi; Chino, Masamichi; Yamazawa, Hiromi; Nagai, Haruyasu; Moriuchi, Shigeru*; Ishikawa, Hirohiko*; Adachi, Takashi*; Kojima, Hiromi*; Okano, Hiroshi*; Odagawa, Fumiaki*; et al.
JAERI-Tech 2001-034, 137 Pages, 2001/06
no abstracts in English
Nagai, Haruyasu; Terada, Hiroaki; Chino, Masamichi
Tenki, 48(4), p.11 - 14, 2001/04
no abstracts in English
Hayashi, Takashi; Chino, Masamichi; Yamazawa, Hiromi; Moriuchi, Shigeru; Ishikawa, Hirohiko*; Adachi, Takashi*; Kojima, Hiromi*
JAERI-Data/Code 99-037, 318 Pages, 1999/08
JAERI-Data-Code-99-037.pdf:13.89MB
no abstracts in English
Hayashi, Takashi; Chino, Masamichi; Yamazawa, Hiromi; Moriuchi, Shigeru*; Ishikawa, Hirohiko*; Adachi, Takashi*; Kojima, Hiromi*
JAERI-Data/Code 99-036, 322 Pages, 1999/08
JAERI-Data-Code-99-036.pdf:14.37MB
no abstracts in English
Kitabata, Hideyuki*; Chino, Masamichi
JAERI-Data/Code 99-012, 47 Pages, 1999/03
JAERI-Data-Code-99-012.pdf:2.82MB
no abstracts in English
Yamazawa, Hiromi
Nihon Genshiryoku Gakkai-Shi, 41(2), p.114 - 116, 1999/00
Times Cited Count：2 Percentile：21.17(Nuclear Science & Technology)no abstracts in English
