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Journal Articles

Application of a communication-avoiding generalized minimal residual method to a gyrokinetic five dimensional Eulerian code on many core platforms

Idomura, Yasuhiro; Ina, Takuya*; Mayumi, Akie; Yamada, Susumu; Matsumoto, Kazuya*; Asahi, Yuichi*; Imamura, Toshiyuki*

Proceedings of 8th Workshop on Latest Advances in Scalable Algorithms for Large-Scale Systems (ScalA 2017), p.7_1 - 7_8, 2017/11

A communication-avoiding generalized minimal residual (CA-GMRES) method is applied to the gyrokinetic toroidal five dimensional Eulerian code GT5D, and its performance is compared against the original code with a generalized conjugate residual (GCR) method on the JAEA ICEX (Haswell), the Plasma Simulator (FX100), and the Oakforest-PACS (KNL). The CA-GMRES method has $$sim 3.8times$$ higher arithmetic intensity than the GCR method, and thus, is suitable for future Exa-scale architectures with limited memory and network bandwidths. In the performance evaluation, it is shown that compared with the GCR solver, its computing kernels are accelerated by $$1.47times sim 2.39times$$, and the cost of data reduction communication is reduced from $$5%sim 13%$$ to $$sim1%$$ of the total cost at 1,280 nodes.

Journal Articles

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Journal Articles

An Approach to DNA crystallization using the thermal reversible process of DNA duplexes

Chatake, Toshiyuki*; Sazaki, Gen*; Kikko, Tatsuhiko*; Fujiwara, Satoru; Ishikawa, Takuya*; Matsumoto, Osamu*; Morimoto, Yukio*

Crystal Growth & Design, 10(3), p.1090 - 1095, 2010/03

 Times Cited Count:4 Percentile:48.51(Chemistry, Multidisciplinary)

We propose a technique for DNA crystallization using the thermal reversible process of DNA: a conversion between a double-stranded DNA (dsDNA) and two single-stranded DNAs (ssDNAs) with temperatures. We investigated the solubility of the crystals of a DNA hexamer d(CGCGCG) and their melting temperature, at which the thermal conversion occurs. The results obtained suggest that the conversion from a dsDNA to ssDNAs results in an increase in solubility. It was shown that using this temperature-controlled technique, high-grade single crystals of the DNA hexamer could be obtained from a small amount of DNA samples. This easy-to-apply technique would be superior to the conventional vapor diffusion technique in that it allows the solubility of DNA crystals to be controlled with no need for expensive setups.

Journal Articles

Functional aberration of myofibrils by cardiomyopathy-causing mutations in the coiled-coil region of the troponin-core domain

Matsumoto, Fumiko; Maeda, Kayo*; Chatake, Toshiyuki*; Maeda, Yuichiro*; Fujiwara, Satoru

Biochemical and Biophysical Research Communications, 382(1), p.205 - 209, 2009/04

 Times Cited Count:13 Percentile:61.39(Biochemistry & Molecular Biology)

Two cardiomyopathy-causing mutations, E244D and K247R, in human cardiac troponin T (TnT) are located in the coiled-coil region of the Tn-core domain. To elucidate effects of mutations in this region on the regulatory function of Tn, we measured Ca$$^{2+}$$-dependent ATPase activity of myofibrils containing various mutants of TnT at these residues. The results confirmed that the mutant E244D increases the maximum ATPase activity without changing the Ca$$^{2+}$$ sensitivity. The mutant K247R was shown for the first time to have the effect similar to the mutant E244D. Furthermore, various TnT mutants (E244D, E244M, E244A, E244K, K247R, K247E, and K247A) showed various effects on the maximum ATPase activity while the Ca$$^{2+}$$ sensitivity was unchanged. Molecular dynamics simulations of the Tn-core containing these TnT mutants suggested that the hydrogen-bond network formed by the side chains of neighboring residues around residues 244 and 247 is important for Tn to function properly.

Journal Articles

Progress in R&D efforts on the energy recovery linac in Japan

Sakanaka, Shogo*; Ago, Tomonori*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; Harada, Kentaro*; Hiramatsu, Shigenori*; Honda, Toru*; et al.

Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.205 - 207, 2008/06

Future synchrotron light sources based on the energy-recovery linacs (ERLs) are expected to be capable of producing super-brilliant and/or ultra-short pulses of synchrotron radiation. Our Japanese collaboration team is making efforts for realizing an ERL-based hard X-ray source. We report recent progress in our R&D efforts.

Journal Articles

Discussions in Symposium "Neutron dosimetry in neutron fields; From detection techniques to medical applications"

Tanimura, Yoshihiko; Sato, Tatsuhiko; Kumada, Hiroaki; Terunuma, Toshiyuki*; Sakae, Takeji*; Harano, Hideki*; Matsumoto, Tetsuro*; Suzuki, Toshikazu*; Matsufuji, Naruhiro*

Hoshasen, 34(2), p.135 - 139, 2008/04

Recently the traceability system (JCSS) of neutron standard based on the Japanese law "Measurement Act" has been instituted. In addition, importance of the neutron dose evaluation has been increasing in not only the neutron capture medical treatment but also the proton or heavy particle therapy. Against such a background, a symposium "Neutron dosimetry in neutron fields; From detection techniques to medical applications" was held on March 29, 2008 and recent topics on the measuring instruments and their calibration, the traceability system, the simulation technique and the medical applications were introduced. This article summarizes the key points in the discussion at the symposium.

JAEA Reports

Development of sodium disposal technology; Experiment of sodium compound solidification process

Matsumoto, Toshiyuki; Oura, Masato*; Yato, Yasuo*

JAEA-Research 2007-049, 73 Pages, 2007/07

JAEA-Research-2007-049.pdf:40.32MB

A large amount of sodium containing radioactive waste will come up at the time of final shutdown/ decommission of FBR plant. The radioactive waste is managed as solid state material in a closed can in Japan. As for the sodium, there is no established method to convert the radioactive sodium to solid waste. Further, the sodium is highly reactive. Thus, it is recommended to convert the sodium to a stable substance before the solidification process. One of the stabilizing methods is conversion of sodium into sodium hydroxide solution. These stabilization and solidification processes should be safe, economical, and efficient. In order to develop such sodium disposal technology, nonradioactive sodium was used and a basic experiment was performed. Waste-fluid Slag Solidification method was employed as the solidification process of sodium hydroxide solution. Experimental parameters were mixing ratio of the sodium hydroxide and the slag solidification material, temperature and concentration of the sodium hydroxide. The best parameters were obtained to achieve the maximum filling ratio of the sodium hydroxide under a condition of enough high compressive strength of the solidified waste. In a beaker level test, the solidified waste was kept in a long term and it was shown that there was no change of appearance, density, and also the compressive strength was kept at a target value. In a real scale test, homogeneous profiles of the density and the compressive strength were obtained. The compressive strength was higher than the target value. It was shown that the Waste-fluid Slag Solidification method can be applied to the solidification process of the sodium hydroxide solution, which was produced by the stabilization process.

Journal Articles

Ultra large-scale exact-diagonalization for confined fermion-Hubbard model on the Earth Simulator; Exploration of superfluidity in confined strongly-correlated systems

Yamada, Susumu; Imamura, Toshiyuki*; Kano, Takuma; Ohashi, Yoji*; Matsumoto, Hideki*; Machida, Masahiko

Journal of the Earth Simulator, 7, p.23 - 35, 2007/06

In order to explore a possibility of superfluidity in confined strongly-correlated fermion systems, e.g., nano-scale cuprate High-Tc superconductors and atomic Fermi gases loaded on an optical lattice, we implement an exact diagonalization code for their mathematical model, i.e., a trapped Hubbard model on the Earth Simulator. We compare two diagonalization algorithms, the traditional Lanczos method and a new algorithm, the preconditioned conjugate gradient (PCG) method, and find that when using the PCG the total CPU time can be reduced to 1/3 $$sim$$ 1/5 compared to the former one since the convergence can be dramatically improved by choosing a good preconditioner and the communication overhead is much more efficiently concealed in the PCG method. Consequently, such a performance improvement enables us to do systematic studies for several parameters. Numerical simulation results reveal that an unconventional type of pairing specific to the confined system, which can cause superfluidity, develops under a strong repulsive interaction.

JAEA Reports

Development of sodium conversion technology; Development of sodium conversion basic experiment apparatus

Matsumoto, Toshiyuki; Yoshida, Eiichi; Suzuki, Shigeaki*; Yasu, Tomohisa*

JAEA-Technology 2007-035, 35 Pages, 2007/03

JAEA-Technology-2007-035.pdf:23.9MB

In the future, a large amount of sodium (Na) containing radioactive wastes must be processed at the time of final shutdown/ decommissioning of FBR plant or radioactive sodium facilities in Japan. Therefore, its disposal technology should be established in consideration of economical efficiency, safety, etc. In the existing technology, since the method of processing sodium directly into radioactive waste is not established, conversion of sodium into chemically stable material can be considered. Then, basic experiments in which sodium was injected at 10 kg/h into solution of sodium hydroxide (NaOH) were conducted, with the improved Sodium Conversion Test Apparatus (SCOT). The conditions of NaOH solution were temperature of 100$$^{circ}$$C, and NaOH concentration of 45-50 wt%. Consequently, the injected sodium reacted completely in the NaOH solution, and NaOH temperature, NaOH concentration, etc. were controlled properly. It validated that the system of this apparatus was appropriate. Moreover, in case sodium is injected into NaOH solution, a nozzle blockades sometimes. Therefore, the methods to eliminate the cause of nozzle blockage were examined.

JAEA Reports

Development of sodium conversion technology; Method and basic features of sodium conversion process

Matsumoto, Toshiyuki; Yoshida, Eiichi; Suzuki, Shigeaki*; Yasu, Tomohisa*

JAEA-Research 2007-038, 32 Pages, 2007/03

JAEA-Research-2007-038.pdf:5.06MB

Decommissioning of a sodium cooled fast reactor or an experimental facility which used radioactive sodium will bring a lot of radioactive sodium. However, technology to deal with such the radioactive sodium and decommission is not well established in Japan. Then, basic experimental study has been carried out in order to find and estimate an economic and safety process of the radioactive sodium decommission. There were some examples in overseas to convert the sodium into sodium hydroxide via sodium-water reaction. This method was examined by a basic sodium conversion test apparatus. In the experiment, liquid metal sodium was injected into the sodium hydroxide. Influences of temperature and concentration of the sodium hydroxide were investigated. Nitrogen gas was injected into the sodium hydroxide as atomizing gas in order to protect the sodium injection nozzle and also to mix the sodium. Then the gas flow rate was also varied to see the desired effects. Injected sodium temperature and mass flow rate were fixed at 200$$^{circ}$$C and 10kg/h, respectively. The atomizing gas flow rate, the temperature and concentration of the sodium hydroxide were varied in ranges of 60-100 l/min, 70-100$$^{circ}$$C and 40-60wt%, respectively. The influences of these parameters on the sodium conversion reaction were evaluated. The experiments showed that increase of the atomizing gas resulted in stable injection of the sodium and also larger reaction area. The temperature of the sodium hydroxide had small influences on the reaction, however, the sodium injection nozzle tended to choke up when the temperature was less than 70$$^{circ}$$C. The lower concentration resulted in larger temperature fluctuation and also enlarged the reaction area. Unstable reaction, for example, sudden increase of reaction rate due to excess sodium, was not found under the conditions above listed ranges and stable sodium conversion was confirmed.

JAEA Reports

None

Nakayama, Fusao*; Enokido, Yuji*; Yoshida, Eiichi; Matsumoto, Toshiyuki; Hasebe, Shinichi

JNC-TN9420 2005-001, 115 Pages, 2005/03

JNC-TN9420-2005-001.pdf:9.24MB

None

JAEA Reports

Study on the prediction accuracy of nuclide generation and depletion with JENDL

Okumura, Keisuke; Oki, Shigeo*; Yamamoto, Munenari*; Matsumoto, Hideki*; Ando, Yoshihira*; Tsujimoto, Kazufumi; Sasahara, Akihiro*; Katakura, Junichi; Matsumura, Tetsuo*; Aoyama, Takafumi*; et al.

JAERI-Research 2004-025, 154 Pages, 2005/01

JAERI-Research-2004-025.pdf:19.46MB

This report summarizes the activity (FY2000-2003) of Working Group (WG) on Evaluation of Nuclide Generation and Depletion under Subcommittee on Nuclear Fuel Cycle of Japanese Nuclear Data Committee. In the WG, analyses of Post Irradiation Examinations have been carried out for UO$$_{2}$$ and MOX fuels irradiated in PWRs, BWRs and FBRs, and for actinide samples irradiated in fast reactors, by using ORIGEN or more detailed calculation codes with their libraries based on JENDL-3.2, JENDL-3.3 and other foreign nuclear data files. From these results, current prediction accuracy and problems for evaluation of nuclide generation and depletion are discussed. Furthermore, this report covers other products of our activity; development of the ORIGEN libraries for PWR, BWR and FBR based on JENDL-3.3, study on introduction of neutron spectrum index to ORIGEN calculations, and results of questionnaire survey on desirable accuracy of ORIGEN calculations.

Journal Articles

Remote handling systems for ITER

Honda, Tsutomu*; Hattori, Yukiya*; Holloway, C.*; Martin, E.*; Matsumoto, Yasuhiro*; Matsunobu, Takashi*; Suzuki, Toshiyuki*; Tesini, A.*; Baulo, V.*; Haange, R.*; et al.

Fusion Engineering and Design, 63-64, p.507 - 518, 2002/12

 Times Cited Count:16 Percentile:27.16

The requirement to reduce the construction cost for ITER as compared with the 1998 ITER design,has led to a reduction in the size of the ITER machine and a number of design changes which have an impact on the remote maintenance of ITER. Major components to be considered for remote handling(RH) include the divertor cassettes,shield blanket modules,neutral beamline components, as well as in-port components,which are integrated with the port shield plug such as auxiliary heating equipment,limiters and test blanket modules. The design of the following equipment has been adapted for the smaller machine with reduced access space for the RH equipment:the RH equipment used for the in-vessel RH operationsto be deployed from the casks,the RH equipment that is used to remove the in-port assemblies(port plugs),as well as the remotely operated casks,which can be attached to and removed from vacuum vessel ports by using double -door systems. Defective components are loaded in transfer casks and moved to the hot cell facility by means of a remotely-operated air floatation system attached underneath the cask,where they dock against identical port interfaces and unload the component for remote refurbishment and/or waste storage.

JAEA Reports

Operation experience of MOX fuel loaded heavy water reactor

Shiratori, Yoshitake; Furubayashi, Toshiyuki; Matsumoto, Mitsuo

PNC-TN3410 91-031, 47 Pages, 1991/11

ugen has been operating safely and smoothly for twelve years using mainly plutonium-uranium mixed oxide (mox) fuels, and much operation data has been accumulated during this time. Fugen's core management has been established, and its core characteristics have been evaluated through the operation. the effect of $$^{241}$$am accumulation and plutonium composition ratio must be considered when many mox fuels are used in a thermal reactor. Calculation accuracy of core analysis code is good and core characteristics are well evaluated by the consideration of these factors. Fuel inspection shows that there is no big difference between mox and uo$$_{2}$$ fuel.

Oral presentation

The Development of sodium conversion technology, 2; Improvement of sodium injection nozzle and stable operating condition

Matsumoto, Toshiyuki; Yoshida, Eiichi; Suzuki, Shigeaki*; Yasu, Tomohisa*

no journal, , 

no abstracts in English

Oral presentation

Development of long-life vitrification melter, 4; Evaluation of fundamental performances of the melter

Yamashita, Teruo; Masaki, Toshio; Shiotsuki, Masao; Yamasaki, Akito*; Ito, Toshiyuki*; Ono, Isamu*; Matsumoto, Shiro*

no journal, , 

no abstracts in English

Oral presentation

Development of long-life vitrification melter, 13; Evaluation of temperature distribution of the melter

Yamashita, Teruo; Masaki, Toshio; Kojima, Keizo; Shiotsuki, Masao; Ito, Toshiyuki*; Ono, Isamu*; Matsumoto, Shiro*

no journal, , 

no abstracts in English

Oral presentation

Chirped pulse amplification laser using Nd:glass zig-zag slab pumped by laser diodes

Sueda, Keiichi*; Kurita, Takashi*; Kawashima, Toshiyuki*; Yamakawa, Koichi; Kawanaka, Junji*; Sekine, Takashi*; Zhao, B.*; Jiang, Y.*; Matsumoto, Osamu*; Fujita, Masayuki*; et al.

no journal, , 

no abstracts in English

Oral presentation

Construction of a BNCT facility using an 8MeV high power proton linac in Ibaraki

Kobayashi, Hitoshi*; Kurihara, Toshikazu*; Matsumoto, Hiroshi*; Yoshioka, Masakazu*; Matsumoto, Noriyuki*; Kumada, Hiroaki*; Matsumura, Akira*; Sakurai, Hideyuki*; Hiraga, Fujio*; Kiyanagi, Yoshiaki*; et al.

no journal, , 

no abstracts in English

Oral presentation

Evaluation of creep damage in mod. 9Cr-1Mo steels by non-linear eddy current testing

Matsumoto, Takanori*; Uchimoto, Tetsuya*; Takagi, Toshiyuki*; Takaya, Shigeru

no journal, , 

Mod. 9Cr-1Mo steel is used in advanced fossil power plants. It becomes more important to manage creep damage because temperature and pressure in operating conditions become higher. In this study, it is an objective to evaluate microstructure change due to creep damage by nonlinear eddy current testing. Firstly, relationship between signal of nonlinear eddy current testing and microstructure of creep test samples of mod. 9Cr-1Mo steel was investigated. Next, nonlinear electro-magnetic analysis was performed by using FEM, and then models describe the relation between microstructure and magnetic property was discussed. As result, the possibility of quantitative evaluation of microstructure change due to creep damage by the proposed method is shown.

22 (Records 1-20 displayed on this page)