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Journal Articles

PSTEP: Project for solar-terrestrial environment prediction

Kusano, Kanya*; Ichimoto, Kiyoshi*; Ishii, Mamoru*; Miyoshi, Yoshizumi*; Yoden, Shigeo*; Akiyoshi, Hideharu*; Asai, Ayumi*; Ebihara, Yusuke*; Fujiwara, Hitoshi*; Goto, Tadanori*; et al.

Earth, Planets and Space (Internet), 73(1), p.159_1 - 159_29, 2021/12

 Times Cited Count:6 Percentile:51.19(Geosciences, Multidisciplinary)

The PSTEP is a nationwide research collaboration in Japan and was conducted from April 2015 to March 2020, supported by a Grant-in-Aid for Scientific Research on Innovative Areas from the Ministry of Education, Culture, Sports, Science and Technology of Japan. It has made a significant progress in space weather research and operational forecasts, publishing over 500 refereed journal papers and organizing four international symposiums, various workshops and seminars, and summer school for graduate students at Rikubetsu in 2017. This paper is a summary report of the PSTEP and describes the major research achievements it produced.

Journal Articles

Evaluation of RBE-weighted doses for various radiotherapy beams based on a microdosimetric function implemented in PHITS

Takada, Kenta*; Sato, Tatsuhiko; Kumada, Hiroaki*; Sakurai, Hideyuki*; Sakae, Takeji*

Journal of Physics; Conference Series, 1662, p.012004_1 - 012004_6, 2020/10

The University of Tsukuba has developed a treatment planning system (TPS) for boron neutron capture therapy (BNCT) that uses a Monte Carlo algorithm as a dose calculation engine. In the system, RBE-weighted dose can be also estimated using the microdosimetric function implemented in PHITS. In this study, we calculated the RBE-weighted doses for various radiation therapy beams. Comparison between the calculated results for different radiation therapy beams as well as verification of the calculated data will be presented at the meeting.

JAEA Reports

Study on modeling and analysis of groundwater flow with inverse analysis, 2 (Joint research)

Onoe, Hironori; Yamamoto, Shinya*; Kohashi, Akio; Ozaki, Yusuke; Sakurai, Hideyuki*; Masumoto, Kiyoshi*

JAEA-Research 2018-003, 84 Pages, 2018/06

JAEA-Research-2018-003.pdf:17.44MB

In this study, numerical experiments considered hydrogeological structures, which has high heterogeneity around the Mizunami Underground Research Laboratory and inverse analysis using in-situ data were carried out. The results showed that concentration of hydrogeological structure to be estimated and location of monitoring point is important for application of inverse analysis. Furthermore, it is concluded that inverse analysis using hydraulic response due to pumping test is effective for hydrogeological characterization.

Journal Articles

Validation of the physical and RBE-weighted dose estimator based on PHITS coupled with a microdosimetric kinetic model for proton therapy

Takada, Kenta*; Sato, Tatsuhiko; Kumada, Hiroaki*; Koketsu, Junichi*; Takei, Hideyuki*; Sakurai, Hideyuki*; Sakae, Takeji*

Journal of Radiation Research, 59(1), p.91 - 99, 2018/01

 Times Cited Count:34 Percentile:88.03(Biology)

Evaluation of the relative biological effectiveness (RBE)-weighted dose is indispensable in the treatment planning of proton and carbon ion therapies. In this study, we validate the RBE-weighted dose calculated by microdosimetric kinetic model (MKM) in tandem with the Monte Carlo particle transport code PHITS for proton therapy using the full simulation geometry for the beam line of the Proton Medical Research Center at the University of Tsukuba. The physical dose and RBE-weighted dose on the central axis for a 155 MeV monoenergetic and spread-out Bragg peak beam of 60 mm width are evaluated by the method. The calculated results generally agree with the corresponding experimental data very well, though overestimations by approximately 3.2% and 15% at the maximum are observed for the physical and RBE-weighted doses, respectively. This research completes the computational microdosimetric approach based on a combination of PHITS and MKM for all types of radiotherapy that require RBE evaluations.

JAEA Reports

Three-dimensional stress analysis of reflooding tunnel during submerging process using crack tensor model at Mizunami Underground Research Laboratory

Ozaki, Yusuke; Matsui, Hiroya; Kuwabara, Kazumichi; Tada, Hiroyuki*; Sakurai, Hideyuki*; Kumasaka, Hiroo*; Goke, Mitsuo*; Kobayashi, Shinji*

JAEA-Research 2016-007, 125 Pages, 2016/06

JAEA-Research-2016-007.pdf:34.66MB

In Mizunami Underground Research Laboratory (MIU), the stress analysis of fractured rock have been performed with crack tensor model. In MIU, a reflooding test is performed at 500m stage. In this study, stress analysis of rock during submerging process of the tunnel is performed by using crack tensor model. The deformation of the rock under different water levels in the tunnel is simulated. The stress condition by high pressure due to inflow of groundwater into tunnel is also estimated. These simulation are performed under assumption that groundwater does not permeate into rock for the estimation of maximum pressure acting on the rock. The stress analysis with consideration of permeation of groundwater into rock is also conducted for the estimation of stress condition after the diffusion of water pressure in tunnel. The results of these analyses lead the conclusion that the pressure of the rock reaches the groundwater pressure near the face of tunnel when the tunnel is submerged.

JAEA Reports

Study on modeling and analysis of groundwater flow with inverse analysis (Joint research)

Kohashi, Akio; Onoe, Hironori; Yamamoto, Shinya*; Honda, Makoto*; Sakurai, Hideyuki*; Masumoto, Kiyoshi*

JAEA-Research 2015-022, 89 Pages, 2016/03

JAEA-Research-2015-022.pdf:27.85MB

In Japan, high-level radioactive waste (HLW) will be emplaced in a stable host rock formation deeper than 300 meters underground for geological disposal. It is important to understand heterogeneous distribution of hydraulic conductivity from the viewpoints of the safety assessment of geological disposal of HLW and construction of underground facilities. Inverse analysis based on the transient data is an efficient technique for estimating the heterogeneous distribution. In this study, numerical experiments with the adjoint state method and the ensemble Kalman filter were carried out in order to understand effective method for application of these inverse analysis. As a result of this study, the capability of each analysis techniques was shown.

JAEA Reports

A Study on the method of an equivalent continuous body modelling using crack tensor theory in the Mizunami Underground Research Laboratory Project

Sanada, Hiroyuki; Sato, Toshinori; Tanno, Takeo*; Hikima, Ryoichi*; Tada, Hiroyuki*; Kumasaka, Hiroo*; Ishii, Takashi*; Sakurai, Hideyuki*

JAEA-Research 2014-006, 124 Pages, 2014/06

JAEA-Research-2014-006.pdf:11.26MB

Japan Atomic Energy Agency has been implementing the Mizunami Underground Research Laboratory (MIU) Project in order to develop the comprehensive investigation techniques for the geological environment and the engineering techniques to construct a deep underground laboratory in crystalline rock. In the rock mechanical study in the MIU Project, the development of the evaluation method for the excavation damaged zone due to excavation of shafts and research galleries is one of the important issues. In this report, crack tensor was calculated using the tunnel wall mapping and rock mechanical test results in the shaft and research galleries in the MIU. Two dimension excavation analysis was conducted at the Ventilation Shaft and GL -500 m Sub Stage using the calculated crack tensor at GL -500 m. Based on calculated crack tensor at GL 500 m, validation of the crack tensor at GL -500 m estimated during Phase I was verified. Relative error of crack tensor was calculated in order to examine variation of relative error to the scale of observation areas.

Journal Articles

Multistep lattice-voxel method utilizing lattice function for Monte-Carlo treatment planning with pixel based voxel model

Kumada, Hiroaki*; Saito, Kimiaki; Nakamura, Takemi; Sakae, Takeji*; Sakurai, Hideyuki*; Matsumura, Akira*; Ono, Koji*

Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.238 - 241, 2010/10

Journal Articles

Geostatistical modeling of groundwater properties and assessment of their uncertainties

Yamamoto, Shinya*; Honda, Makoto*; Sakurai, Hideyuki*; Suzuki, Makoto*; Sanada, Hiroyuki; Sugita, Yutaka; Matsui, Hiroya

Proceedings of 14th Annual Conference of the International Association for Mathematical Geosciences (IAMG 2010) (CD-ROM), 12 Pages, 2010/09

The distribution of groundwater properties is important for understanding of the deep underground hydrogeological environments in the design of the HLW disposal facilities. This study proposes a geostatistical system for modeling the chemical properties of groundwater which have a correlation with the resistivity data obtained from widespread and exhaustive survey. The proposed system is consists of two methodologies (resistivity data integration using Simple Kriging with varying local mean (SKlm) and 3D distribution modeling of hydro-chemical properties of groundwater estimated by SKlm algorithm). 2 types of uncertainty are considered: (1) Aleatory uncertainty; (2) Epistemic uncertainty. As a result, the uncertainties of the proposal model have been estimated lower than other traditional model's.

Journal Articles

Geostatistical modeling of groundwater properties and assessment of thier uncertainties

Honda, Makoto*; Yamamoto, Shinya*; Sakurai, Hideyuki*; Suzuki, Makoto*; Sanada, Hiroyuki; Sugita, Yutaka; Matsui, Hiroya

Doboku Gakkai Rombunshu, C, 66(3), p.609 - 624, 2010/08

This paper proposes a geostatistical system for modeling the groundwater properties which have a correlation with the ground resistivity data obtained from widespread and exhaustive electromagnetic survey. That is, the methodology for the integration of resistivity data measured by various methods and the methodology for modeling the groundwater properties using the integrated resistivity data has been developed. The proposed system has also been validated using the data obtained in the surface-based investigations of the Horonobe URL project. Additionally, the quantification of uncertainties in the estimated model has been tried by numerical simulations based on the data. As a result, the uncertainties of the proposal model have been estimated lower than other traditional model's.

Journal Articles

Heavy-ion-induced bystander killing of human lung cancer cells; Role of gap junctional intercellular communication

Harada, Kosaku*; Nonaka, Tetsuo*; Hamada, Nobuyuki*; Sakurai, Hideyuki*; Hasegawa, Masatoshi*; Funayama, Tomoo; Kakizaki, Takehiko*; Kobayashi, Yasuhiko; Nakano, Takashi*

Cancer Science, 100(4), p.684 - 688, 2009/04

 Times Cited Count:56 Percentile:75.67(Oncology)

Journal Articles

Basic characteristics of a newly developed Si/CdTe Compton camera for medical imaging

Kawachi, Naoki; Watanabe, Shigeki; Sato, Takahiro; Arakawa, Kazuo; Takeda, Shinichiro*; Ishikawa, Shinnosuke*; Aono, Hiroyuki*; Watanabe, Shin*; Yamaguchi, Mitsutaka*; Takahashi, Tadayuki*; et al.

2008 IEEE Nuclear Science Symposium Conference Record (CD-ROM), p.1540 - 1543, 2008/10

JAEA Reports

Study on geological environment model using geostatistics method (Joint research)

Honda, Makoto*; Sakurai, Hideyuki*; Suzuki, Makoto*; Iwasa, Kengo*; Matsui, Hiroya

JAEA-Research 2008-038, 73 Pages, 2008/06

JAEA-Research-2008-038.pdf:18.44MB

The purpose of this study is to develop a geostatistical procedure for modeling on geological environments and to evaluate quantitative relationship between amount of geological information and reliability of the models using data sets obtained in surface-based investigation phase (Phase 1) of the Horonobe Underground Research Laboratory Project. This study is a joint research with Shimizu Corporation carried out in four years from FY2003 to FY2006. In the first three years, by using the data sets obtained by the geological investigations in each FY, three dimensional models of the resistivity, the chemical composition of groundwater and the hydraulic conductivity were built and undated by the geostatistical method developed in this study. The relationship between the amount of information and the reliability of the models were demonstrated as well through comparisons of the models at each step which corresponds to the investigation stage in each FY. In FY2006, as a summary of this study in the final FY, to confirm the validity of the present method, the above three models were compared with models built by a conventional method. Relationship between the procedure of geological survey and the reliability of the models were also studied by newly computing three sets of models based on fictitious investigation plans, their procedures are different form the actual one, and comparing these four models.

JAEA Reports

Excavation disturbance analysis based on Crack Tensor Model and Virtual Fracture Model for predicting the rock mass behavior during excavation of shafts and research galleries at the Mizunami Underground Research Laboratory

Seno, Yasuhiro; Nakama, Shigeo; Sato, Toshinori*; Goke, Mitsuo*; Tada, Hiroyuki*; Sakurai, Hideyuki*

JAEA-Research 2007-081, 120 Pages, 2008/01

JAEA-Research-2007-081.pdf:13.48MB

A 3D Crack Tensor Model analysis was carried out to predict the rock mass behavior of the complex (articulated) section at -500 m. Properties were chosen based on the Rock Mechanics Model constructed in the Surface-based Investigation Phase (Phase I). The Virtual Fracture Model was applied to analyze the change the hydraulic conductivity.

JAEA Reports

Study on geological environment model using geostatistics method (Joint research)

Honda, Makoto*; Suzuki, Makoto*; Sakurai, Hideyuki*; Iwasa, Kengo*; Matsui, Hiroya

JAEA-Research 2007-028, 91 Pages, 2007/04

JAEA-Research-2007-028.pdf:17.93MB

The purpose of this study is to develop the geostatistical procedure for modeling geological environments and to evaluate the quantitative relationship between the amount of information and the reliability of the model using the data sets obtained in Phase 1 of the Horonobe Underground Research Laboratory Project. In FY 2006 research, the data obtained from the deep boreholes which were executed in FY 2005 were newly used in addition to the data sets used in the previous study. And the hydrogeological models were built by using the same geostatistical procedure developed in the previous study. The relationship between the amount of information and the reliability of the model was demonstrated as well through a comparison of the models at each step which corresponds to the investigation stage in each FY. Furthermore, in the case of hydro-chemical model, the modeling procedure was applied to each dissolved principal component and their characteristics of distribution were clarified.

Journal Articles

Bystander killing of human lung cancer cells by heavy charged particle irradiation

Harada, Kosaku*; Nonaka, Tetsuo*; Hamada, Nobuyuki*; Funayama, Tomoo; Sakurai, Hideyuki*; Sakashita, Tetsuya; Wada, Seiichi*; Kawamura, Hidemasa*; Hasegawa, Masatoshi*; Kobayashi, Yasuhiko; et al.

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 102, 2007/02

Journal Articles

Study on the improvement in reliability of hydrogeological model through progress of investigation; An Example of geostatistical hydraulic conductivity model

Honda, Makoto*; Suzuki, Makoto*; Sakurai, Hideyuki*; Iwasa, Kengo*; Matsui, Hiroya

Dai-41-Kai Jiban Kogaku Kenkyu Happyokai Happyo Koenshu, p.51 - 52, 2006/07

no abstracts in English

Journal Articles

Geostatistical modeling of hydrogeological environment using resistivity distribution measured by various methods

Honda, Makoto*; Sakurai, Hideyuki*; Iwasa, Kengo*; Suzuki, Makoto*; Matsui, Hiroya

Heisei-18 Nendo (2006 Nen) Shigen, Sozai Gakkai Shunki Taikai Koenshu (I) Shigen Hen, p.49 - 52, 2006/03

no abstracts in English

Journal Articles

Research of disease onset mechanism by determining the distribution of intracellular trace elements using an in-air micro-PIXE analyzer system

Nakano, Takashi*; Arakawa, Kazuo; Sakurai, Hideyuki*; Hasegawa, Masatoshi*; Yuasa, Kazuhisa*; Saito, Etsuko*; Takagi, Hitoshi*; Nagamine, Takeaki*; Kusakabe, Takahiko*; Takada, Hisashi*; et al.

International Journal of PIXE, 16(1&2), p.69 - 76, 2006/00

A new program was started out to create a new medical scientific field, which is consisting of radiation oncology and nuclear medicine, utilizing the advanced accelerator and ion beam technology. An in-air micro-PIXE analyzer system, which is among the most important technical basis of the program, was upgraded to improve accuracy of elemental mapping for samples having thickness variation in a scope of microbeam scanning. In the program, on the other hand, in order to approach important bio-medical problems on cancer, intracellular dynamics of the trace elements according to mechanism of development of diseases were studied using this system. This paper outlines this program and shows the system upgraded, and results of preliminary studied about the problems.

JAEA Reports

Study on geological environment model using geostatic method

Honda, Makoto*; Suzuki, Makoto*; Sakurai, Hideyuki*; Iwasa, Kengo*; Matsui, Hiroya

JNC TY5400 2004-001, 255 Pages, 2004/03

JNC-TY5400-2004-001.pdf:51.46MB

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