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Otsuka, Yusuke*; Kanazawa, Naoya*; Hirayama, Motoaki*; Matsui, Akira*; Nomoto, Takuya*; Arita, Ryotaro*; Nakajima, Taro*; Hanashima, Takayasu*; Ukleev, V.*; Aoki, Hiroyuki; et al.
Science Advances (Internet), 7(47), p.eabj0498_1 - eabj0498_9, 2021/11
Times Cited Count：7 Percentile：40.96(Multidisciplinary Sciences)
=28 and 
=50; Spectroscopy of 
ZnShand, C. M.*; Podoly
k, Zs.*; G
rska, M.*; Doornenbal, P.*; Obertelli, A.*; Nowacki, F.*; Otsuka, T.*; Sieja, K.*; Tostevin, J. A.*; Tsunoda, T.*; et al.
Physics Letters B, 773, p.492 - 497, 2017/10
Times Cited Count：25 Percentile：87.36(Astronomy & Astrophysics)Takeuchi, Tomoaki; Yamamoto, Keiichi; Otsuka, Noriaki; Shibata, Hiroshi; Shibata, Akira; Takemoto, Noriyuki; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; Fujihara, Yasuyuki*; et al.
KURRI Progress Report 2014, P. 108, 2015/07
Investigation of a relation between output power and brightness of Cherenkov light of a specific fuel element at KUR by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. The results indicate that the inhomogeneous distribution of output power and the shadow of the control-rod guide tubes and the other irradiation equipment have significant effects on the brightness of the Cherenkov light. These effects could be suppressed by using a number of cameras located at various positions.
Otsuka, Noriaki; Takeuchi, Tomoaki; Yamamoto, Keiichi; Shibata, Akira; Kimura, Nobuaki; Takemoto, Noriyuki; Tanimoto, Masataka; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; et al.
KURRI Progress Report 2013, P. 215, 2014/10
Investigation of a relation between reactor power and brightness of Cherenkov light at Kyoto University Research reactor (KUR) by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. Analyzing the brightness value of individual RGB color component at each pixel, some of the G and B brightness values reached the maximum value of 8-bit binary number, i.e. 255, above about 2-3 MW. Therefore, we corrected the G and B brightness values by the R signals whose brightness value did not saturate even at 5 MW, the maximum reactor power of KUR. Then, the total brightness value was in proportion to the reactor power after the correction. These results indicate the reactor power can be estimated by the observation of Cherenkov light.
detectorTakeuchi, Tomoaki; Otsuka, Noriaki; Shibata, Akira; Tsuchiya, Kunihiko
Journal of Nuclear Science and Technology, 51(7-8), p.939 - 943, 2014/07
Times Cited Count：4 Percentile：30.92(Nuclear Science & Technology)no abstracts in English
Komeda, Masao; Ozu, Akira; Haruyama, Mitsuo; Takase, Misao*; Kureta, Masatoshi; Nakatsuka, Yoshiaki; Zaima, Naoki; Nakashima, Shinichi; Otsuka, Yoshimasa
Proceedings of INMM 55th Annual Meeting (Internet), 9 Pages, 2014/07
We have researched and developed the FNDI method for a long time through experiments in NUCEF in JAEA Tokai. Referred from the pilot machine, we designed a demonstrator, called as JAWAS-N, for applying to non-destructive assay tools for uranium waste drums in JAEA Ningyo. In this paper, we present the modeling and the simulations concerning JAWAS-N's characteristics, and discuss for practical use compared analytical results with obtained some experimental data.
Shibata, Akira; Takeuchi, Tomoaki; Otsuka, Noriaki; Saito, Takashi; Onoda, Shinobu; Oshima, Takeshi; Tsuchiya, Kunihiko
JAEA-Technology 2013-043, 24 Pages, 2014/01
JAEA-Technology-2013-043.pdf:2.76MB
The big tsunami wave caused by the Great East Japan Earthquake triggered station black out of the Fukushima Daiichi Nuclear Power Plant. The schedule until ending of the decommission is shown in the guidance from Japanese government. But the dose rate in the reactor vessel is quite high and it is not possible to specify the position of melted fuel debris by visual inspection. That is one of the most important issues in this process. This report describes the development of Self Powered Gamma Detector (SPGD) for the purpose to specify the position of melted fuel debris and situation in the reactor by measuring rate in the reactor of the Fukushima Daiichi Nuclear Power Plant. The irradiation examinations by changing the parameter of emitters figure were performed and the dependency of SPGD output on emitter shape was summarized.
Takeuchi, Tomoaki; Shibata, Akira; Nagata, Hiroshi; Kimura, Nobuaki; Otsuka, Noriaki; Saito, Takashi; Nakamura, Jinichi; Matsui, Yoshinori; Tsuchiya, Kunihiko
Proceedings of 3rd Asian Symposium on Material Testing Reactors (ASMTR 2013), p.52 - 58, 2013/11
In-pile instrumentation systems in present LWR's are indispensable to monitor all situations during reactor operation and reactor shut down. However, those systems did not work sufficiently under the conditions like as the severe accident at the Fukushima Dai-Ichi Nuclear Power Station. Therefore, based on the irradiation measurement technique of experiences accumulated in JMTR, the developments of reactor instrumentation systems to prevent severe core damage accident in advance have been started. The development objects are four instrumentation systems, which are a solid electrolysis type hydrogen concentration sensor, a water gauge of thermocouple type equipped with the heater, a -ray detector of self-powered type SPGD, and an image analysis system of Cherenkov light for quantification of in-reactor information by CCD cameras. After the developments, the in-pile verification tests of four instrumentation systems are planned at the JMTR.
Shibata, Akira; Miura, Kuniaki*; Takeuchi, Tomoaki; Otsuka, Noriaki; Nakamura, Jinichi; Tsuchiya, Kunihiko
JAEA-Technology 2013-024, 21 Pages, 2013/10
JAEA-Technology-2013-024.pdf:12.62MB
In the Fukushima-Daiichi Nuclear Power Plant Accident, the measurements of water level in pressure vessel and spent fuel pool were impossible due to station blackout, and it resulted in difficulty for countermeasures against the accidents and for understanding of the situations of reactor core after accidents. Therefore, we started to develop a new water level sensor for l with high reliability, which works with small electric power. This report describes reviews of conventional water level sensor and design and production of new water level sensor. After production of the sensor, performance tests were performed between room temperature and about 95 
C, and the it was confirmed that the sensor is able to measure water level with the accuracy of 
20 mm. As the results, a perspective to use the new water level sensor as water level indicator for spent fuel pools and reactor vessels after severe accident.
Takeuchi, Tomoaki; Shibata, Akira; Nagata, Hiroshi; Miura, Kuniaki*; Sano, Tadafumi*; Kimura, Nobuaki; Otsuka, Noriaki; Saito, Takashi; Nakamura, Jinichi; Tsuchiya, Kunihiko
Proceedings of 5th International Symposium on Material Testing Reactors (ISMTR-5) (Internet), 8 Pages, 2012/10
In-pile instrumentation systems in present LWR's are indispensable to monitor all situations during reactor operation and reactor shut down. However, those systems did not work sufficiently under the conditions of the severe accident at the Fukushima Dai-ichi (F1) Nuclear Power Plant. Based on instrumentation and irradiation experiences accumulated in JMTR, the developments of reactor instrumentation systems to prevent severe core damage accident in advance have been started. The development objects are water level gauge utilizing heating, self-powered -ray detector, hydrogen concentration gauge, and analysis system for imaging and quantification of in-reactor information using Cherenkov light.
Shibata, Keiichi; Iwamoto, Osamu; Nakagawa, Tsuneo; Iwamoto, Nobuyuki; Ichihara, Akira; Kunieda, Satoshi; Chiba, Satoshi; Katakura, Junichi; Otsuka, Naohiko*
Journal of the Korean Physical Society, 59(2), p.1046 - 1051, 2011/08
Times Cited Count：18 Percentile：69.22(Physics, Multidisciplinary)In JENDL-4, much emphasis is placed on the improvements of FP and MA data. For achieving this, new nuclear model codes POD and CCONE were developed, since experimental data are very scarce for those nuclei. The global coupled-channel optical model parameters, which were obtained in the wide mass region, were used for the evaluation of cross sections. Thermal cross sections of actinides were determined by carefully examining available experimental data. Special care was taken for the resonance region of 
U in order to reproduce measured criticalities and Na-void reactivities for U fueled fast-neutron cores. As for FP, resolved resonance parameters were updated for more than 100 nuclei. The cross sections of above the resonance region were evaluated by using the POD and CCONE codes. Fission product yield data were obtained from the ENDF/B-VII.0 data with some modifications. The new library, which contains neutron data for 406 nuclei, will be made available in 2010.
Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Hodotsuka, Yasuyuki; Tagami, Masahiko; Ishida, Hideaki; Hayano, Akira; Kurihara, Arata; Yuguchi, Takashi
JAEA-Research 2010-039, 131 Pages, 2011/01
JAEA-Research-2010-039.pdf:25.36MB
Tono Geoscientific Unit of Geological Isolation and Development Directoratte is performing Mizunami Underground Research Laboratory (MIU) Project, which is a broad scientific study of the deep geological environment as a basis of research and development for geological disposal of nuclear wastes, in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in fractured crystalline rock. The MIU Project has three overlapping 3 phases, with a total duration of 20 years. The project goals of the MIU Project from Phase I through to Phase III are: to establish techniques for investigation, analysis and assessment of the deep geological environment, and to develop a range of engineering for deep underground application. Currently, the project is under the Phase II. This document presents the overview of results of the research and development on "geology" performed in fiscal year 2008, with regard to the Phase II goal.
Shibata, Keiichi; Iwamoto, Osamu; Nakagawa, Tsuneo*; Iwamoto, Nobuyuki; Ichihara, Akira; Kunieda, Satoshi; Chiba, Satoshi; Furutaka, Kazuyoshi; Otsuka, Naohiko*; Osawa, Takaaki*; et al.
Journal of Nuclear Science and Technology, 48(1), p.1 - 30, 2011/01
Times Cited Count：1611 Percentile：100(Nuclear Science & Technology)The fourth version of Japanese Evaluated Nuclear Data Library has been produced. In the new library, much emphasis is placed on the improvements of fission product and minor actinoid data. Two nuclear model codes were developed to evaluate the cross sections of fission products and minor actinoids. Coupled-channel optical model parameters, which can be applied to wide mass and energy regions, were obtained for nuclear model calculations. Thermal cross sections of actinoids were determined by considering recent experimental data or by the systematics of neighboring nuclei. A simultaneous evaluation was performed for the fission cross sections of important uranium and plutonium isotopes above 10 keV. The data on FP were re-evaluated, and new evaluations were performed for 30 nuclides. The data on light elements and structural materials were partly re-evaluated. The new library was released as JENDL-4.0 in May 2010.
Shibata, Keiichi; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Otsuka, Naohiko*; Fukahori, Tokio; Nakagawa, Tsuneo; Katakura, Junichi
Proceedings of 16th Pacific Basin Nuclear Conference (PBNC-16) (CD-ROM), 6 Pages, 2008/10
Evaluated nuclear data play an important role in nuclear engineering. After we released the first version of Japanese Evaluated Nuclear Data Library JENDL-1 about 30 years ago, JENDL has been revised several times by considering the feedback from users and recent experimental data. JENDL-3.3, which was released in 2002, is being used in various fields, and its reliability has been confirmed. We are developing JENDL-4 for innovative reactors with much emphasis on the improvements of FP and MA data. Nuclear model codes were developed. The actinide data were already released as JENDL Actinoid File 2008. The complete library JENDL-4 will be made available in FY2009.
Shibata, Keiichi; Nakagawa, Tsuneo; Fukahori, Tokio; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Otsuka, Naohiko; Katakura, Junichi; Watanabe, Yukinobu*; et al.
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.2, p.727 - 732, 2008/05
General- and special-purpose JENDL data files are being produced in cooperation with the Japanese Nuclear Data Committee. We have developed nuclear model codes to improve the quality of MA and FP data. In the FP region, we obtained global coupled-channel optical model parameters, which can be applied to neutron- and proton-induced reaction data up to 200 MeV. These parameters are used for statistical model calculation. Resolved resonance parameters of MA and FP nuclei were updated to improve the low-energy behavior of the cross sections by using recent measurements. As a follow-up of JENDL-3.3, which was released in 2002, covarainces of several nuclei were estimated for a study on ADS. Concerning special-purpose files, the compilation of the 2007 versions of JENDL High Energy File and Photonulcear Data Files is in the final stage.
Shibata, Keiichi; Nakagawa, Tsuneo; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Fukahori, Tokio; Otsuka, Naohiko; Katakura, Junichi
Proceedings of American Nuclear Society Topical Meeting on Physics of Reactors (PHYSOR 2006) (CD-ROM), 10 Pages, 2006/09
no abstracts in English
(Horvth) (Homoptera: Delphacidae) using hourly catches and a three-dimensional simulation modelOtsuka, Akira*; Watanabe, Tomonari*; Suzuki, Yoshito*; Matsumura, Masaya*; Furuno, Akiko; Chino, Masamichi; Kondo, Tomoya*; Kamimuro, Tsuyoshi*
Agricultural and Forest Entomology, 8(1), p.35 - 47, 2006/02
Times Cited Count：17 Percentile：58.03(Entomology)1 Migration of Sogatella furcifera captured in Japan in the 2003 season were analyzed using hourly catches and a simulation model.2. The catch data showed several clear migration peaks, with average durations of 4 h. The peaks were separated from each other by approximately 12 h, corresponding to the observed fact that planthoppers take off at dusk and dawn.3. The simulation model, together with the hourly catches, enabled an estimation of migration source regions.4. Possible migration sources during our hourly observation period were located in the coastal area of Fujian province in China, as well as Taiwan.
Furuno, Akiko; Chino, Masamichi; Otsuka, Akira*; Watanabe, Tomonari*; Matsumura, Masaya*; Suzuki, Yoshito*
Agricultural and Forest Meteorology, 133(1-4), p.197 - 209, 2005/11
Times Cited Count：21 Percentile：55.78(Agronomy)Transoceanic migration of rice planthoppers was precisely simulated by incorporating several parameters related to the flight behavior with a high performance atmospheric dispersion model. The model consists of an atmospheric dynamic submodel and a particle random-walk submodel for atmospheric dispersion. The model also functions in specifying the release area of the migration of planthoppers. Using this model, we carried out a case study simulating the migration of planthoppers to western Japan in mid-June 1998. In the simulation, 56 areas each with a width of two degrees of latitude and longitude were set as tentative take-off areas. The calculated density of immigrants was compared with each observed density by rank correlation coefficients. Possible migration release areas which showed a high correlation to observations were distributed around 23-27N, including Fujian and Taiwan. An air temperature that allowed the planthoppers to fly continuously and flight duration were critical parameters for the simulation results.
Shibata, Keiichi; Nakagawa, Tsuneo; Fukahori, Tokio; Ichihara, Akira; Iwamoto, Osamu; Otsuka, Naohiko*; Katakura, Junichi
AIP Conference Proceedings 769, p.171 - 176, 2005/05
The presentation deals with the activities on JENDL. JENDL-4 is being developed as a general purpose library. This library will include charged-particle and photon induced reaction data as well as spontaneous fission data for a limited number of nuclei in addition to neutron induced reaction data. The maximum incident energy can be extended to higher values than 20 MeV depending on data needs. Key subjects are improvements of accuracy of minor actinide and FP data, evaluations of covariances and so on. Quality assurance is regarded as important for JENDL-4. As special purpose files, we released the JENDL High Energy File and Photonuclear Data File this year. For the development of ADS, the Actinide File is being made. Furthermore,covariance data for some nuclei are also evaluated for ADS. Nuclear model codes are developed in order to reflect recent advances in nuclear theory on data evalulations. For users' covenience, we are working on the development of the Combined System for Nuclear Data Utilization, Circulaiton and Transfer.
Otsuka, Naohiko; Aikawa, Masayuki*; Suda, Takuma*; Naito, Kenichi*; Korennov, S.*; Arai, Koji*; Noto, Hiroshi*; Onishi, Akira*; Kato, Kiyoshi*; Nakagawa, Tsuneo; et al.
AIP Conference Proceedings 769, p.561 - 564, 2005/05
A web-based search and plot system for nuclear reaction data has been developed, covering experimental data in EXFOR format and evaluated data in ENDF format. The system is implemented for Linux OS, with Perl and MySQL used for CGI scripts and the database manager, respectively. Two prototypes for experimental and evaluated data are presented.
