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Kato, Takemi*; Sugawara, Katsuaki*; Ito, Naohiro*; Yamauchi, Kunihiko*; Sato, Takumi*; Oguchi, Tamio*; Takahashi, Takashi*; Shiomi, Yuki*; Saito, Eiji; Sato, Takafumi*
Physical Review Materials (Internet), 4(8), p.084202_1 - 084202_6, 2020/08
Times Cited Count:4 Percentile:19.71(Materials Science, Multidisciplinary)Saito, Kimiaki; Mikami, Satoshi; Ando, Masaki; Matsuda, Norihiro; Kinase, Sakae; Tsuda, Shuichi; Sato, Tetsuro*; Seki, Akiyuki; Sanada, Yukihisa; Wainwright-Murakami, Haruko*; et al.
Journal of Radiation Protection and Research, 44(4), p.128 - 148, 2019/12
Miyamura, Hiroko; Takemiya, Hiroshi; Wu, H.-Y.*; Takahashi, Shigeo*
Kashika Joho Gakkai-Shi, 36(143), p.152 - 156, 2016/10
Broad survey on the distribution of the air dose rate has been performed after the accident at the Fukushima Daiichi Nuclear Power Plant continuously. The surveyed monitoring datasets are stored in a database and are made available to the public. Recently, the size of the datasets have been significantly increased as more detailed measurements in space and time are available, and effective reduction of the size of the datasets is necessary for visualizing and exploring such large scale datasets. However, if the datasets are not carefully reduced, we often miss a part of important features of the distribution data. Therefore, we develop an effective Level of Detail control (LoD) method for retaining critical features of the distribution. In the method, the global and local features of the distribution are extracted by means of differential topology analyses. Then, the simplified data is created by edge collapse operation with taking into account these features of the data.
Saito, Kimiaki; Tanihata, Isao*; Fujiwara, Mamoru; Saito, Takashi*; Shimoura, Susumu*; Otsuka, Takaharu*; Onda, Yuichi*; Hoshi, Masaharu*; Ikeuchi, Yoshihiro*; Takahashi, Fumiaki; et al.
Journal of Environmental Radioactivity, 139, p.308 - 319, 2015/01
Times Cited Count:225 Percentile:98.79(Environmental Sciences)Seki, Akiyuki; Takemiya, Hiroshi; Takahashi, Fumiaki; Saito, Kimiaki; Tanaka, Kei*; Takahashi, Yutaka*; Takemura, Kazuhiro*; Tsuzawa, Masaharu*
Progress in Nuclear Science and Technology (Internet), 4, p.47 - 50, 2014/04
The radionuclide distribution database and map system, which provide basic information for evaluations and countermeasures of the Fukushima nuclear accident, are explained. Due to massive earthquake and tsunami, Fukushima Dai-ichi Nuclear Power Plant has been damaged and had spread out radioactive materials around the Fukushima site. It is necessary to collect, analyze, and provide the information of radioactivity correctly and immediately. We developed two providing systems to identify the current distribution of released radionuclides and support decontamination activities.
Toyoshima, Yoshiyuki*; Takahashi, Akemi*; Tanaka, Hisaki*; Watanabe, Jun*; Mogi, Yoshinobu*; Yamazaki, Tatsuo*; Hamada, Ryoko*; Iwashita, Kazuhiro*; Sato, Katsuya; Narumi, Issei
Mutation Research; Fundamental and Molecular Mechanisms of Mutagenesis, 740(1-2), p.43 - 49, 2012/12
Times Cited Count:18 Percentile:48.99(Biotechnology & Applied Microbiology)Yanagie, Hironobu*; Kumada, Hiroaki*; Nakamura, Takemi; Higashi, Shushi*; Ikushima, Ichiro*; Morishita, Yasuyuki*; Shinohara, Atsuko*; Fujiwara, Mitsuteru*; Suzuki, Minoru*; Sakurai, Yoshinori*; et al.
Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.157 - 160, 2010/10
Seki, Akiyuki; Suzuki, Kenta*; Takahashi, Yoshitomo*; Matsubara, Takeshi*; Suto, Shigeo*; Saito, Kimiaki; Takemiya, Hiroshi
no journal, ,
JAEA had collected and published radioactive monitoring data provided individually by government offices and local governments and so on. The amount of those data which were unified in same display format and accuracy had become enormous by six years after the accident had passed. To understand how much the radionuclide distribution changed, new contents which were prepared in maps and graphs were added in the site for publishing.
Seki, Akiyuki; Takemiya, Hiroshi; Saito, Osamu; Saito, Kimiaki; Tanaka, Kei*; Takahashi, Yutaka*; Takemura, Kazuhiro*; Tsuzawa, Masaharu*
no journal, ,
The system for saving and providing the data which are related to the radionuclides in Fukushima prefecture and the neighboring prefectures has been developed. The data mainly include the dose-rate and the analysis result of the soil and water samples. The Center for Computational Science and e-Systems developed the system under the study on distribution of radioactive substances around Fukushima Dai-ichi Nuclear Power Plant founded by MEXT. Proceeding with the installation of the data which are collected by MEXT and Fukushima prefecture, the system are being enhanced more.
Seki, Akiyuki; Takemiya, Hiroshi; Takahashi, Fumiaki; Saito, Kimiaki; Tanaka, Kei*; Takahashi, Yutaka*; Takemura, Kazuhiro*; Tsuzawa, Masaharu*
no journal, ,
The construction of the database and map systems, which provide basic information for evaluations and countermeasures of the Fukushima nuclear accident, are explained. Fukushima Daiichi Nuclear Power Plant had been damaged and spread out radioactive materials around there on March 2011. There are still a lot of requests to know the distribution of radioactive material from government, local government, residents, and/or researchers. In order to meet those requests, we developed two systems to provide those data to the public. One of the systems is a database system which is designed to provide quantitative data for detailed analysis. Another is a map system which provides intuitive images for the qualitative estimation.
Takahashi, Akemi*; Toyoshima, Yoshiyuki*; Tanaka, Hisaki*; Watanabe, Jun*; Yamazaki, Tatsuo*; Iwashita, Kazuhiro*; Mikami, Shigeaki*; Sato, Katsuya; Nozawa, Shigeki; Narumi, Issei
no journal, ,
no abstracts in English
Seki, Akiyuki; Takemiya, Hiroshi; Takahashi, Fumiaki; Saito, Kimiaki; Tanaka, Kei*; Takahashi, Yutaka*; Takemura, Kazuhiro*; Tsuzawa, Masaharu*
no journal, ,
Radioactive database and contamination map for the accident of Fukushima Dai-ichi Nuclear Power Plant are described. It is necessary to obtain precise data on the contamination conditions. Both systems have been developed to provide information to identify the current distribution of released materials and to support decontamination planning. The former is designed to provide quantitative data for detailed analysis, while another to provide intuitive images for the qualitative estimation. They contain air dose rates at around 2,200 locations within approximately 100 km from the plant, and radionuclide concentration data at each location. The vehicle-borne survey results are also included for the purpose of ascertaining the distribution of radioactive substances around roads in detail. All the data have been measured during the first investigation conducted in June, and the second in December 2011. The systems will become open to the public at the site of JAEA soon.
Miyamura, Hiroko; Idomura, Yasuhiro; Takemiya, Hiroshi; Sakurai, Daisuke*; Wu, H.-Y.*; Takahashi, Shigeo*
no journal, ,
We survey the distribution of accumulated radioactive substances and assess the air dose rate. The surveyed datasets are stored in a database and are made available to the public. In addition, we develop a visualization tool that enables ones to download the datasets and then visualize them on one's computer environment. Recently, the size of the datasets have been significantly extended as more detailed measurements in space and time are available, and effective reduction of the size of the datasets is necessary for analyzing such large scale datasets. However, if the datasets are not carefully reduced, we often miss a part of important features in the distribution data. Therefore, we develop an effective Level of Detail control (LoD) method for retaining critical features of the distribution. In the method, the structure of two dimensional data that represents a global feature of the distribution is extracted by means of differential topology analyses. The data size is reduced by considering local features of the data, while retaining its global structure.
Takahashi, Akemi*; Toyoshima, Yoshiyuki*; Tanaka, Hisaki*; Watanabe, Jun*; Yamazaki, Tatsuo*; Iwashita, Kazuhiro*; Mikami, Shigeaki*; Sato, Katsuya; Nozawa, Shigeki; Narumi, Issei
no journal, ,
no abstracts in English
Miyamura, Hiroko; Takahashi, Shigeo*; Idomura, Yasuhiro; Takemiya, Hiroshi
no journal, ,
We propose a level-of-detail control method for environmental monitoring datasets. The radioactive substance emitted due to the accident at the nuclear power plant in Fukushima was spread by an air current. The air dose distribution map suggests that the air current was not able to rise above a certain height in the mountainous district. We propose a new level-of-detail control method that reduces the visualization element while retaining features of two or more data elements such as the distribution of air dose and height for analyzing the relationship between two or more datasets.
Seki, Akiyuki; Suzuki, Kenta; Takahashi, Yoshitomo; Matsubara, Takeshi; Suto, Shigeo; Saito, Kimiaki; Takemiya, Hiroshi; Murakami, Haruko*
no journal, ,
After the Fukushima Daiichi Nuclear Power Plant accident, a lot of monitoring studies had been conducted to collect the precious data which are important for the estimation and prediction of the radionuclide distribution. However, those monitoring databases were not convenient for users because their formats were not unified and they are provided as PDF files. Moreover those databases ware published on the independent websites operated by each organization. JAEA developed the database which provides the monitoring data in an unique format on the same website. The database provides not only numerical data but also visualization data following users' needs.
Seki, Akiyuki; Suzuki, Kenta; Takahashi, Yoshitomo; Matsubara, Takeshi; Suto, Shigeo; Saito, Kimiaki; Takemiya, Hiroshi
no journal, ,
Japan Atomic Energy Agency developed a tool which automatically collects the monitoring data published by the related organizations separately. The data was formatted in a common style and published on the same website called "Database for Radioactive Substance Monitoring Data". Since a lot of environmental monitoring results have been accumulated in the past five years since the accident, new contents, which help us understand the change of the distribution of radionuclide by analyzing their time histories, were released on the website.