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Journal Articles

Spatio-temporal mapping; A Technique for overview visualization of time-series datasets

Miyamura, Hiroko; Hayashi, Sachiko*; Suzuki, Yoshio; Takemiya, Hiroshi

Progress in Nuclear Science and Technology (Internet), 2, p.603 - 608, 2011/10

Numerical simulations have recently increased in scale and have often output high dimensional datasets. This makes it difficult for users to quickly grasp physical phenomena involved in such datasets. To overcome this difficulty, we propose a spatio-temporal mapping technique (spatio-temporal map) by using an information visualization technique. The spatio-temporal map is generated by mapping the values of a 3D and time-evolving physical quantity into a 2D space with spatial and temporal axes. Here, 3D spatial information is condensed into one dimension by subdividing a target model with an octree. By using the map, users can quickly find regions of interest (ROI). In addition, users can interactively change several aspects of the map such as its resolution and color coding method. By applying the spatio-temporal map to a full-scale 3D vibration simulator for an entire nuclear power plant, we confirmed that the map is a useful technique to quickly identify appropriate ROI.

Journal Articles

Spatio-temporal mapping; A Technique for overview visualization of time-series datasets

Miyamura, Hiroko; Hayashi, Sachiko*; Suzuki, Yoshio; Takemiya, Hiroshi

Proceedings of Joint International Conference of 7th Supercomputing in Nuclear Application and 3rd Monte Carlo (SNA + MC 2010) (USB Flash Drive), 4 Pages, 2010/10

We propose a spatio-temporal information mapping technique and the map design function. The spatio-temporal map is created by spatio-temporal information mapping technique. In the map, the change of a physical quantity is allocated in two-dimensional space with spatial and temporal information in each dimension. By the way, it is helpful for users to change the map interactively, such as changing the resolution of the map, colored physical quantity, and so on. Therefore, the function enabling users to design the map by changing the tree structure is also developed.

Journal Articles

R&D of atomic energy grid infrastructure AEGIS

Suzuki, Yoshio; Tatekawa, Takayuki; Kim, G.; Kino, Chiaki; Miyamura, Hiroko; Teshima, Naoya; Hayashi, Sachiko*; Aoyagi, Tetsuo; Takemiya, Hiroshi; Nakajima, Norihiro

Keisan Kogaku Koenkai Rombunshu, 15(2), p.1051 - 1054, 2010/05

We have developed the Atomic Energy Grid InfraStructure (AEGIS) for establishing computational infrastructure for nuclear field. In this R&D we have inherited the knowledge and skills in ITBL Infrastructure developed in the national project ITBL (Information Technology Based Laboratory), which aims at establishment of virtual research environment where supercomputers and data bases are connected by network. Here we have focused on two issues: improvements of safety and usability. For the safety, we have made the authentication mechanism double with both the personal certification and the machine certification. For the usability, we have developed the grid-enabled client API to use grid functions on a user terminal. By those R&Ds, we have successfully contributed to various nuclear researches, such as "full scale 3D vibration simulator for an entire nuclear power plant", "simulation for predicting quake-proof capability of nuclear power plants", and so on.

JAEA Reports

GSALab computer code for global sensitivity analysis

Liu, Q.; Homma, Toshimitsu; Nishimaki, Yuichiro*; Hayashi, Hiroko*; Terakado, Masato*; Tamura, Satoshi*

JAEA-Data/Code 2010-001, 57 Pages, 2010/03

JAEA-Data-Code-2010-001.pdf:16.81MB

For a risk assessment model of an engineering system, the uncertainties in the model inputs propagate through the model and lead to the uncertainty in the model output. In order to evaluate the model output uncertainty and the contribution of each model input to the output uncertainty, the computer code GSALab, which is based on Monte Carlo simulations, has been developed. It is composed of three parts, namely, random samples generation, uncertainty analysis and sensitivity analysis. In the part of sensitivity analysis, several global sensitivity indicators, including the popularly used variance-based indicators, are implemented. In addition, the GUI (Graphical User Interface) of GSALab has been developed for the user's convenience. In addition to risk assessment models, it is also possible to use GSALab for uncertainty and sensitivity analysis of a wide class of mathematical models.

Journal Articles

Overview visualization of time-series dataset

Miyamura, Hiroko; Hayashi, Sachiko; Suzuki, Yoshio; Takemiya, Hiroshi

FUJITSU Famirikai Rombunshu (Internet), 15 Pages, 2010/03

With the improvement in the performance of supercomputers, numerical simulations have become complex and the simulation results have become large-scale. It has made the interpretation of simulation results difficult. Therefore, we propose a spatio-temporal visualization system "spatio-temporal map" for interpreting the time-series simulation results. The spatio-temporal map is an information visualization technique useful for specifying the feature area from simulation and measurement results. In the map, the change of a physical quantity is allocated in two-dimensional space with spatial and temporal information in each dimension. In this paper, we demonstrate the effectiveness of the proposed method by applying it to the large scale simulation results.

Journal Articles

Data exploration system for the evaluation of numerical simulation results

Miyamura, Hiroko; Nakajima, Kohei*; Suzuki, Yoshio; Hayashi, Sachiko; Takemiya, Hiroshi; Nakajima, Norihiro

Zen NEC C&C Shisutemu Yuza Kai Heisei-21-Nendo Rombunshu (CD-ROM), 12 Pages, 2010/02

In this paper, we propose data exploration system for the evaluation of numerical simulation results. With the improvement in the performance of supercomputers, numerical simulations have become larger and more complex, which has made the interpretation of simulation results more difficult. Moreover, occasionally, users cannot evaluate numerical simulation results, even though they have spent a great deal of time, because interactive visualization is impossible for such large-scale data. Therefore, we herein propose a data exploration system with which users evaluate large-scale time-series data that has been obtained in a parallel and distributed environment. The proposed system allows users to simultaneously visualize and analyze data in both the global and local scales.

Journal Articles

Role of anomalous transport in onset and evolution of neoclassical tearing modes

Konovalov, S. V.; Mikhailovskii, A. B.*; Ozeki, Takahisa; Takizuka, Tomonori; Shirokov, M. S.*; Hayashi, Nobuhiko

Plasma Physics and Controlled Fusion, 47(12B), p.B223 - B236, 2005/12

 Times Cited Count:7 Percentile:26.36(Physics, Fluids & Plasmas)

Neoclassical Tearing Modes, NTMs, are known to limit the maximum attainable plasma pressure, degrade confinement and, at worst, culminate in disruption of the tokamak discharges. Key role in NTM evolution belongs to the radial profiles of the plasma flow, temperature and density which are determined by the conjunction of the longitudinal and cross-filed transport arising from thermal conduction, particle diffusion, and viscosity. In this report the influence of anomalous perpendicular heat transport and anomalous ion perpendicular viscosity on early stage of the NTM evolution is studied theoretically.

Journal Articles

Infuluence of anomalous transport phenomena on onset of neoclassical tearing modes in tokamaks

Konovalov, S. V.; Mikhailovskii, A.*; Ozeki, Takahisa; Takizuka, Tomonori; Shirokov, M. S.*; Hayashi, Nobuhiko

Proceedings of 20th IAEA Fusion Energy Conference (FEC 2004) (CD-ROM), 8 Pages, 2004/11

Influence of anomalous perpendicular heat transport and anomalous perpendicular viscosity on conditions of Neoclassical Tearing Mode onset is studied theoretically. Series of different parallel transport mechanisms competitive to anomalous cross-island heat conductivity in the perturbed temperature profile are considered.In the transport threshold model, magnetic curvature effect is as much important as bootstrap drive weakened by the finite perpendicular heat transport. Perpendicular viscosity brings island-rotation-frequency dependence of the transport threshold model.

Journal Articles

Development of a code MOGRA for predicting the migration of ground additions and its application to various land utilization areas

Amano, Hikaru; Takahashi, Tomoyuki*; Uchida, Shigeo*; Matsuoka, Shungo*; Ikeda, Hiroshi*; Hayashi, Hiroko*; Kurosawa, Naohiro*

Journal of Nuclear Science and Technology, 40(11), p.975 - 979, 2003/11

 Times Cited Count:2 Percentile:19.75(Nuclear Science & Technology)

MOGRA is a migration prediction code for toxic ground additions including radioactive materials in a terrestrial environment. MOGRA consists of computational codes that are applicable to various evaluation target systems, and can be used on personal computers. The computational code has the dynamic compartment analysis block, GUI for computation parameter settings and results displays, data bases. The compartments are obtained by classifying various natural environments into groups that exhibit similar properties. A hypothetical combination of land usage was supposed to check the function of MOGRA. The land usage was consisted from cultivated lands, forests, uncultivated lands, urban area, river, and lake. Each land usage has its own inside model which is basic module. Also supposed was homogeneous contamination of the surface land from atmospheric deposition of $$^{137}$$Cs (1.0 Bq/m$$^{2}$$). The system analyzed the dynamic changes of $$^{137}$$Cs concentrations in each compartment, fluxes from one compartment to another compartment.

Journal Articles

Status of development of a code for predicting the migration of ground additions: MOGRA

Amano, Hikaru; Takahashi, Tomoyuki*; Uchida, Shigeo*; Matsuoka, Shungo*; Ikeda, Hiroshi*; Hayashi, Hiroko*; Kurosawa, Naohiro*

JAERI-Conf 2003-010, p.32 - 36, 2003/09

MOGRA (Migration Of GRound Additions) is a migration prediction code for toxic ground additions including radioactive materials in a terrestrial environment. MOGRA consists of computational codes that are applicable to various evaluation target systems, and can be used on personal computers. The computational code has the dynamic compartment analysis block at its core, the graphical user interface (GUI) for computation parameter settings and results displays, data files and so on. The compartments are obtained by classifying various natural environments into groups that exhibit similar properties. MOGRA has varieties of databases, which consist of radionuclides decay chart, distribution coefficients between solid and liquid, transfer factors from soil to plant, transfer coefficients from feed to beef and milk, concentration factors, and age dependent dose conversion factors for many radionuclides. Here the status of development of MOGRA is presented.

Journal Articles

Application of MOGRA for migration of contaminants through different land utilization areas

Amano, Hikaru; Takahashi, Tomoyuki*; Uchida, Shigeo*; Matsuoka, Shungo*; Ikeda, Hiroshi*; Hayashi, Hiroko*; Kurosawa, Naohiro*

JAERI-Conf 2003-010, p.112 - 121, 2003/09

The functionality of MOGRA is being verified by applying it in the analyses of the migration rates of radioactive substances from the atmosphere to soils and plants and flow rates into the rivers. This has been achieved by also taking their mode classifications into consideration. In this report, a hypothetical combination of land usage was supposed to check the function of MOGRA. The land usage was consisted from cultivated lands, forests, uncultivated lands, urban area, river, and lake. Each land usage has its own inside model which is basic module. Also supposed was homogeneous contamination of the surface land from atmospheric deposition of Cs-137 (1.0 Bq/m$$^{2}$$). The system can analyze the dynamic changes of Cs-137 concentrations in each compartment, fluxes from one compartment to another compartment.

Journal Articles

Construction of river transfer models for MOGRA

Hayashi, Hiroko*; Matsuoka, Shungo*; Takahashi, Tomoyuki*; Amano, Hikaru

JAERI-Conf 2003-010, p.122 - 130, 2003/09

Two dynamic compartment models were constructed as basic river models for MOGRA (Migration Of GRound Additions), an environmental-load effect predicting code. One is 1 component river model, in which radionuclides in particulate form and dissolved form are considered to be in equilibrium in the river water. Another one is 2 component river model, in which particulate form and dissolved form are considered to be different component and are separately compartmentalized. In each model the river sediment is set in a compartment, and the sedimentation of particulate form and resuspension of radionuclides in the river sediment are taken into account.To verify the analysis function of the constructed models, calculation conditions were set using data of Cs-137 concentration in the river water derived from Kuji river, Japan, and analysis was carried out. Comparing two models, almost no difference is seen when sedimentation velocity is low, while there is apparent difference when sedimentation velocity is high.

Journal Articles

Equipment of model template for a code predicting the migration of ground additions, MOGRA

Takahashi, Tomoyuki*; Amano, Hikaru; Uchida, Shigeo*; Ikeda, Hiroshi*; Matsuoka, Shungo*; Hayashi, Hiroko*; Kurosawa, Naohiro*

Kankyo Eisei Kogaku Kenkyu, 17(3), p.340 - 344, 2003/07

no abstracts in English

Oral presentation

Cerebral methodology based computing for estimating validity of simulation results

Suzuki, Yoshio; Hayashi, Sachiko; Miyamura, Hiroko

no journal, , 

Our challenge is to estimate the validity of simulation results by establishing "Cerebral Methodology Based Computing (CMC)". The estimation of the validity is indispensable to accurately predict phenomena by using simulation. It is difficult to estimate the validity from a single simulation because the simulation contains uncertainties and ambiguities. We have proposed CMC as the computing methodology which enables us to estimate the validity of results with both deductive and inductive approaches, similar to the human thinking process. To realize CMC, we have constructed the system which enables us to execute both deductive simulations and inductive simulations, and then combine results of those simulations in an integration process. We have applied the system to a thermal displacement analysis of a nuclear power plant and confirmed the usefulness of the system.

Oral presentation

Visualization system for the evaluation of numerical simulation results

Miyamura, Hiroko; Hayashi, Sachiko; Suzuki, Yoshio; Takemiya, Hiroshi

no journal, , 

We propose a visualization system for the evaluation of numerical simulation results. The proposed system has a multi-window display system that can display several forms of detailed information. The global visualization window displays spatio-temporal information, and the local visualization window displays detailed information around the selected region. By applying the proposed system to the three-dimensional virtual plant vibration simulator, we have confirmed its usefulness for evaluating numerical simulation results.

Oral presentation

Study on distribution and migration of radioactive substances around the Fukushima Daiichi Nuclear Power Plant, 9; Development of prediction models for distribution and migration of radioactive substances within 80 km of the Fukushima Daiichi Nuclear Power Plant

Kinase, Sakae; Takahashi, Tomoyuki*; Sato, Satoshi; Saito, Kimiaki; Kurosawa, Naohiro*; Ryufuku, Susumu*; Hayashi, Hiroko*; Ishibashi, Kazufusa*

no journal, , 

no abstracts in English

Oral presentation

Study on distribution and migration of radioactive substances around the Fukushima Daiichi Nuclear Power Plant; Development of prediction models for a local area

Sato, Satoshi; Kinase, Sakae; Saito, Kimiaki; Takahashi, Tomoyuki*; Kurosawa, Naohiro*; Ryufuku, Susumu*; Hayashi, Hiroko*; Ishibashi, Kazufusa*; Sakamoto, Ryuichi*; Nemoto, Hisashi*

no journal, , 

no abstracts in English

Oral presentation

Study on distribution and migration of radioactive substances around the Fukushima Daiichi Nuclear Power Plant, 8; Characterization of monitoring data by vehicle-borne survey in local area

Sato, Satoshi; Kinase, Sakae; Saito, Kimiaki; Takahashi, Tomoyuki*; Kanno, Mitsuhiro*; Hayashi, Hiroko*; Ishibashi, Kazufusa*; Kurosawa, Naohiro*; Sakamoto, Ryuichi*; Nemoto, Hisashi*

no journal, , 

no abstracts in English

Oral presentation

Study on distribution and migration of radioactive substances around the Fukushima Daiichi Nuclear Power Plant; Development of prediction models for a local area, 3; Ecological half-life evaluation

Ryufuku, Susumu*; Ishibashi, Kazufusa*; Hayashi, Hiroko*; Kurosawa, Naohiro*; Sato, Satoshi; Kinase, Sakae; Saito, Kimiaki; Takahashi, Tomoyuki*

no journal, , 

no abstracts in English

Oral presentation

Diffusion of fluorine from fluoride-containing material in decalcified enamel

Matsuda, Yasuhiro*; Okuyama, Katsushi*; Komatsu, Hisanori*; Oki, Saiko*; Hashimoto, Naoki*; Sano, Hidehiko*; Yamamoto, Hiroko*; Iwami, Yukiteru*; Hayashi, Mikako*; Nomachi, Masaharu*; et al.

no journal, , 

no abstracts in English

22 (Records 1-20 displayed on this page)