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Li, Y.; Katsumata, Genshichiro*; Masaki, Koichi; Hayashi, Shotaro*; Itabashi, Yu*; Nagai, Masaki*; Suzuki, Masahide*; Kanto, Yasuhiro*
Journal of Pressure Vessel Technology, 143(4), p.041501_1 - 041501_8, 2021/08
Times Cited Count：2 Percentile：20.79(Engineering, Mechanical)Li, Y.; Katsumata, Genshichiro*; Masaki, Koichi*; Hayashi, Shotaro*; Itabashi, Yu*; Nagai, Masaki*; Suzuki, Masahide*; Kanto, Yasuhiro*
Proceedings of 25th International Conference on Nuclear Engineering (ICONE-25) (CD-ROM), 10 Pages, 2017/07
In Japan, a PFM analysis code PASCAL (PFM Analysis of Structural Components in Aging LWR) has been developed by the Japan Atomic Energy Agency to evaluate the through-wall cracking frequencies of Japanese reactor pressure vessels (RPVs) considering neutron irradiation embrittlement and pressurized thermal shock transients. In this study, as a part of the verification activities, a working group was established in Japan, with seven organizations from industry, universities and institutes voluntarily participating as members. The source program of PASCAL was released to the members of the working group. Through one year activities, the applicability of PASCAL for structural integrity assessments of domestic RPVs was confirmed with great confidence. This paper presents the details of the verification activities of the working group including the verification plan, approaches and results.
Osakabe, Kazuya*; Masaki, Koichi*; Katsuyama, Jinya; Katsumata, Genshichiro; Onizawa, Kunio; Yoshimura, Shinobu*
Proceedings of 2015 ASME Pressure Vessels and Piping Conference (PVP 2015) (Internet), 8 Pages, 2015/07
A probabilistic fracture mechanics (PFM) analysis method for pressure boundary components is useful to evaluate the structural integrity in a quantitative way. This is because the uncertainties related to influence parameters can be rationally incorporated in PFM analysis. From this viewpoint, the probabilistic approach evaluating through-wall cracking frequencies (TWCFs) of reactor pressure vessels (RPVs) has already been adopted as the regulation on fracture toughness requirements against PTS events in the U.S. As a study of applying PFM analysis to the integrity assessment of domestic RPVs, JAEA has been preparing input data and analysis models to calculate TWCFs using PFM analysis code PASCAL3. In this paper, activities have been introduced such as preparing input data and models for domestic RPVs, verification of PASCAL3, and formulating guideline on general procedures of PFM analysis for the purpose of utilizing PASCAL3. In addition, TWCFs for a model RPV evaluated by PASCAL3 are presented.
Osakabe, Kazuya*; Masaki, Koichi*; Katsuyama, Jinya; Katsumata, Genshichiro; Onizawa, Kunio
Proceedings of 2014 ASME Pressure Vessels and Piping Conference (PVP 2014) (DVD-ROM), 7 Pages, 2014/07
The structural integrity of reactor pressure vessel (RPV) during pressurized thermal shock events is judged to be maintained unless the stress intensity factors at the crack tip is smaller than fracture toughness 
based on deterministic approach in the current Japanese code. Application of a probabilistic fracture mechanics (PFM) analysis method for the structural reliability assessment of RPVs has become attractive recently, because uncertainties of several parameters can be incorporated rationally. According to the PFM analysis method in the U.S., through-wall cracking frequencies (TWCFs) are estimated. In this study, in order to identify the conservatism in the current code, PFM analyses on TWCF have been performed for certain model of RPVs. The result shows that the current assumption in JEAC 4206-2007 is conservative as compared with realistic conditions. Effects of variation of PTS transients on crack initiation frequency and TWCF have been also discussed.
with perovskite- and LiNbO-type structuresInaguma, Yoshiyuki*; Tanaka, Kie*; Tsuchiya, Takeshi*; Mori, Daisuke*; Katsumata, Tetsuhiro*; Oba, Tomonori*; Hiraki, Koichi*; Takahashi, Toshihiro*; Saito, Hiroyuki
Journal of the American Chemical Society, 133(42), p.16920 - 16929, 2011/09
Times Cited Count：84 Percentile：85.78(Chemistry, Multidisciplinary)
C-selective infrared multiple photon dissociation of 
-propiolactone by a free electron laserMiyomoto, Yoshiki*; Majima, Tetsuro*; Arai, Shigeyoshi*; Katsumata, Keiichi*; Akagi, Hiroshi; Maeda, Akihiko*; Hata, Hiroo*; Kuramochi, Koji*; Kato, Yoshiyasu*; Tsukiyama, Koichi*
Nuclear Instruments and Methods in Physics Research B, 269(2), p.180 - 184, 2011/01
Times Cited Count：12 Percentile：66.82(Instruments & Instrumentation)
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Matsuda, Masaaki; Ueda, Hiroaki*; Kikkawa, Akiko*; Tanaka, Yoshikazu*; Katsumata, Koichi*; Narumi, Yasuo*; Inami, Toshiya; Ueda, Yutaka*; Lee, S.-H.*
Nature Physics, 3(6), p.397 - 400, 2007/06
Times Cited Count：104 Percentile：93.31(Physics, Multidisciplinary)Cr-CrCr-based spinel compounds ACrO (A=Mg, Zn, Cd, and Hg) are so far the best model systems for a network of corner-sharing tetrahedrons with isotropic nearest-neighbor antiferromagnetic interactions. The systems exhibit novel spin-Peierls phase transitions from cubic spin liquid to non-cubic N
el states at low temperatures. Recent bulk magnetization studies on CdCrO and HgCrO revealed the magnetic field-induced half magnetization plateau states that are stable over a wide range of field. Recent bulk magnetization studies on CdCrO and HgCrO revealed the magnetic field-induced half magnetization plateau states that are stable over a wide range of field.
-GdSMatsuda, Masaaki; Kikkawa, Akiko*; Katsumata, Koichi*; Ebisu, Shuji*; Nagata, Shoichi*
Journal of the Physical Society of Japan, 74(5), p.1412 - 1415, 2005/05
Times Cited Count：19 Percentile：67.64(Physics, Multidisciplinary)no abstracts in English
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in high magnetic fieldMatsuda, Masaaki; Ueda, Hiroaki*; Kikkawa, Akiko*; Tanaka, Yoshikazu*; Katsumata, Koichi*; Narumi, Yasuo*; Inami, Toshiya; Ueda, Yutaka*; Lee, S.-H.*
no journal, ,
no abstracts in English
Katsumata, Genshichiro; Masaki, Koichi*; Osakabe, Kazuya*; Nishikawa, Hiroyuki*; Katsuyama, Jinya; Nishiyama, Yutaka; Onizawa, Kunio
no journal, ,
To assure the structural integrity of a reactor pressure vessel (RPV) is known as one of the critical issues to maintain the safe long-term operation of a nuclear power plant. In Japan, the assessment methods for RPV integrity, stipulated in the codes and standards, have been endorsed by the regulatory body. Authors have initiated extensive research on the improvement of structural integrity assessment methods of RPVs. In this paper, we describe some research results obtained from the second-year activity. These include the study on revisiting the technical background of the methods, such as loading conditions, postulated crack definition, the other evaluation methods. In addition, studies on probabilistic methods for the applicability to the current rules and the standardization of the probabilistic analysis methods have been presented.
Masaki, Koichi*; Osakabe, Kazuya*; Katsuyama, Jinya; Katsumata, Genshichiro; Onizawa, Kunio
no journal, ,
To assure the structural integrity of a reactor pressure vessel (RPV) is one of the most critical issues to maintain the safe long-term operation of a nuclear power plant. In Japan, the assessment methods for RPV integrity using deterministic fracture mechanics are provided in Japan Electric Association Code (JEAC). Meanwhile, a regulation on the fracture toughness requirements against PTS events based on a probabilistic fracture mechanics (PFM) analysis has been established in the U.S. In this paper, in order to apply probabilistic approach to domestic regulation, sensitivity analyses for flaw density or transient by reference to the data in the U.S. were performed using a PFM analysis code PASCAL3. We evaluated the effect of the flaw density or transient on through-wall cracking frequency (TWCF) and showed the specific example as a practical use of PFM.
Uno, Shumpei; Katsuyama, Jinya; Katsumata, Genshichiro*; Masaki, Koichi*; Osakabe, Kazuya*; Li, Y.
no journal, ,
Assuring the structural integrity of a reactor pressure vessel (RPV) is known as one of the critical issues to maintain the safe long-term operation of a nuclear power plant. Authors have been conducting extensive research on the improvement of structural integrity assessment methods of RPVs. In this paper, we describe some research results obtained from the recent activity including the review on the technical background of the methods and study on probabilistic methods for the applicability to the current code and standard.
Osakabe, Kazuya*; Masaki, Koichi; Miyamoto, Yuhei*; Katsumata, Genshichiro*; Katsuyama, Jinya
no journal, ,
Probabilistic fracture mechanics (PFM) analysis is a useful methodology for quantitative evaluation because failure probabilities can be calculated considering uncertainties of material properties. The recent studies about the classification of uncertainties of inputs for PFM analyses are introduced. In this paper, we describe overseas study on the handling of epistemic uncertainty and aleatory uncertainty in PFM analysis considering reliability.
