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Journal Articles

Metallurgical analysis of lithium test assembly operated for 1200 h

Furukawa, Tomohiro; Kondo, Hiroo; Kanemura, Takuji; Hirakawa, Yasushi; Yamaoka, Nobuo*; Hoashi, Eiji*; Suzuki, Sachiko*; Horiike, Hiroshi*

Fusion Engineering and Design, 89(7-8), p.1674 - 1678, 2014/10

 Times Cited Count:0 Percentile:100(Nuclear Science & Technology)

One key issue in the development of the IFMIF is the corrosion/erosion of the lithium components. At Osaka University, lithium free-surface flow experiments to verify the design of the IFMIF target have been carried out, and the test assembly was operated in high-speed lithium flow for 1200 hours at 300 $$^{circ}$$C. Since the test assembly is important to understand the corrosion/erosion behavior as the demonstration experimental data, the metallurgical analysis was been performed. Slight irregularities which were trace of high-speed lithium flow were observed at the tip of the nozzle. On the other hand, mottled unevenness with many micro-cracks of a few micrometer depths was observed at the inlet of the nozzle, whose velocity ratio was 0.1-0.4 as compared with the nozzle tip. It was estimated that the phenomena was caused by carburizing from liquid lithium, and it was newly proven that carbon control in lithium was also important for corrosion / erosion protection of the IFMIF components.

Journal Articles

Evaluation of applicability of laser-based distance meter to measure Li-jet thickness for IFMIF/EVEDA project

Kanemura, Takuji; Kondo, Hiroo; Hoashi, Eiji*; Suzuki, Sachiko*; Yamaoka, Nobuo*; Horiike, Hiroshi*; Furukawa, Tomohiro; Hirakawa, Yasushi; Wakai, Eiichi

Fusion Engineering and Design, 89(7-8), p.1642 - 1647, 2014/10

 Times Cited Count:11 Percentile:26.91(Nuclear Science & Technology)

In the Engineering Validation and Engineering Design Activities (EVEDA) of the International Fusion Materials Irradiation Facility (IFMIF), a device to measure thickness variation of a high-speed (15 m/s) liquid lithium (Li) jet must be developed. The required measurement precision is 0.1 mm. For this purpose, we newly focused on a laser-based distance meter. This paper describes the result of an applicability test of the new sensor conducted in the Osaka University Li Loop. In the experiment, thickness variation of a Li jet (10 mm in thickness) was measured at the sampling frequency of 500 kHz in the velocity range of 10 to 15 m/s at the Li temperature of 573 K under argon atmosphere of 0.12 MPa. To evaluate the applicability of the device, the measurement precision of the Li level was evaluated. As a result, the precision was approximately 9 $$mu$$m. Thus, we concluded that the laser-based distance meter is applicable to the measurement of the Li target thickness.

Journal Articles

Fabrication and performance test of contact-type liquid level sensor for measuring thickness variation of liquid lithium jet in the IFMIF/EVEDA lithium test loop

Kanemura, Takuji; Kondo, Hiroo; Hoashi, Eiji*; Suzuki, Sachiko*; Yamaoka, Nobuo*; Horiike, Hiroshi*; Furukawa, Tomohiro; Hirakawa, Yasushi; Ida, Mizuho; Matsushita, Izuru*; et al.

Fusion Engineering and Design, 88(9-10), p.2547 - 2551, 2013/10

 Times Cited Count:4 Percentile:60.1(Nuclear Science & Technology)

In the Engineering Validation and Engineering Design Activities (EVEDA) project of the International Fusion Materials Irradiation Facility (IFMIF), thickness variation of a liquid lithium (Li) jet simulating the IFMIF Li target is to be measured in the EVEDA Li Test Loop. This paper presents fabrication and performance tests results of a contact-type liquid level sensor for measuring the jet thickness variation. The sensor can detect contacts between a probe and Li, and analysis of the contact signals yields average jet thickness and amplitude distribution. One of the key fabrication requirements is to drive the probe by 0.1 mm step with positioning precision of 0.01 mm under the vacuum condition of 10$$^{-3}$$Pa. To achieve such requirements, a high torque motor reducer and a friction-reduced ball screw were selected. As a result of the performance tests, the measurement results of the positioning resolution and precision were 0.1 mm and 0.01 mm, respectively.

Journal Articles

Development of lithium target system in engineering validation and engineering design activity of the International Fusion Materials Irradiation Facility (IFMIF/EVEDA)

Wakai, Eiichi; Kondo, Hiroo; Sugimoto, Masayoshi; Fukada, Satoshi*; Yagi, Juro*; Ida, Mizuho; Kanemura, Takuji; Furukawa, Tomohiro; Hirakawa, Yasushi; Watanabe, Kazuyoshi; et al.

Purazuma, Kaku Yugo Gakkai-Shi, 88(12), p.691 - 705, 2012/12

no abstracts in English

Journal Articles

Characteristics of surface oscillation on high speed liquid Li jet

Suzuki, Sachiko*; Hoashi, Eiji*; Kanemura, Takuji; Kondo, Hiroo; Yamaoka, Nobuo*; Horiike, Hiroshi*

Fusion Engineering and Design, 87(7-8), p.1434 - 1438, 2012/08

 Times Cited Count:4 Percentile:61.15(Nuclear Science & Technology)

In the international fusion materials irradiation facility (IFMIF), the high speed liquid metal lithium (Li) wall jet will be used as a target irradiated by two deuteron beams to generate intense neutrons. It is thus important to obtain the surface wave characteristic for the safety and the efficiency of system in the IFMIF. In this paper, the free surface oscillation was measured at 175 mm and 15 mm downstream from the nozzle exit with an electro-contact probe apparatus installed on a renewal flow channel of an Osaka University Li loop. At the velocity of more than 9 m/s, maximum wave amplitudes were about 2 mm, which exceed the current design value of IFMIF. However, the number of large-amplitude waves was found to be very low.

Journal Articles

Engineering design of contact-type liquid level sensor for measuring thickness validation of liquid lithium jet in IFMIF/EVEDA lithium test loop

Kanemura, Takuji; Kondo, Hiroo; Suzuki, Sachiko*; Hoashi, Eiji*; Yamaoka, Nobuo*; Horiike, Hiroshi*; Furukawa, Tomohiro; Ida, Mizuho; Nakamura, Kazuyuki; Matsushita, Izuru*; et al.

Fusion Science and Technology, 62(1), p.258 - 264, 2012/07

 Times Cited Count:4 Percentile:61.15(Nuclear Science & Technology)

In the Engineering Validation and Engineering Design Activities (EVEDA) project of the International Fusion Materials Irradiation Facility (IFMIF), which is one of the Broader Approach (BA) activities, thickness variation of a liquid lithium (Li) jet simulating the IFMIF Li target is planned to be measured in the EVEDA Li Test Loop (ELTL). For this purpose, a contact-type liquid level sensor was developed, which can detect contacts between a probe and Li. Analysis of the contact signals yields average jet thickness and amplitude distribution. One of the key development requirements is to drive the probe by 0.1 mm step with positioning accuracy of 0.01 mm under the vacuum condition of 10$$^{-3}$$Pa. To satisfy such a requirement, the sensor's own weight load and moment load were calculated, and based on those calculation results a powerful motor and a friction-reduced ball screw were selected and strong structure was adopted. We have successfully completed the design work of the sensor.

Journal Articles

Present status of Japanese tasks for lithium target facility under IFMIF/EVEDA

Nakamura, Kazuyuki; Furukawa, Tomohiro; Hirakawa, Yasushi; Kanemura, Takuji; Kondo, Hiroo; Ida, Mizuho; Niitsuma, Shigeto; Otaka, Masahiko; Watanabe, Kazuyoshi; Horiike, Hiroshi*; et al.

Fusion Engineering and Design, 86(9-11), p.2491 - 2494, 2011/10

 Times Cited Count:9 Percentile:35.08(Nuclear Science & Technology)

In IFMIF/EVEDA, tasks for lithium target system are shared to 5 validation tasks (LF1-5) and a design task (LF6). The purpose of LF1 task is to construct and operate the EVEDA lithium test loop, and JAEA has a main responsibility to the performance of the Li test loop. LF2 is a task for the diagnostics of the Li test loop and IFMIF design. Basic research for the diagnostics equipment has been completed, and the construction for the Li test loop will be finished before March in 2011. LF4 is a task for the purification systems with nitrogen and hydrogen. Basic research for the purification equipment has been completed, and the construction of the nitrogen system for the Li test loop will be finished before March in 2011. LF5 is a task for the remote handling system with the target assembly. JAEA has an idea to use the laser beam for cutting and welding of the lip part of the flanges. LF6 is a task for the design of the IFMIF based on the validation experiments of LF1-5.

Journal Articles

Wave period of free-surface waves on high-speed liquid lithium jet for IFMIF target

Kanemura, Takuji; Sugiura, Hirokazu*; Yamaoka, Nobuo*; Suzuki, Sachiko*; Kondo, Hiroo; Ida, Mizuho; Matsushita, Izuru*; Horiike, Hiroshi*

Fusion Engineering and Design, 86(9-11), p.2462 - 2465, 2011/10

 Times Cited Count:5 Percentile:55.14(Nuclear Science & Technology)

Wave period of free-surface waves on a high-speed liquid lithium (Li) jet is very important wave characteristics to investigate for validation of a Li target of the International Fusion Materials Irradiation Facility (IFMIF). In this paper, we report characteristics of wave period measured by a contact-type liquid level sensor. The experiments were conducted at a Li loop in Osaka University. In this loop, a plane Li jet simulating the IFMIF Li target can be controlled at the velocities of up to 15 m/s. Probability density distribution of the measured wave periods was nearly equal to the log-normal distribution. The fact that the wave period distribution is nearly equal to the log-normal distribution has been already identified in the ocean waves which are known for its random property. From present and previous our experimental results, it was concluded that random wave property developed for the ocean waves can apply to the free-surface waves on the Li jet.

Journal Articles

Study on surface wave characteristics of free surface flow of liquid metal lithium for IFMIF

Hoashi, Eiji*; Sugiura, Hirokazu*; Suzuki, Sachiko*; Kanemura, Takuji; Kondo, Hiroo; Yamaoka, Nobuo*; Horiike, Hiroshi*

Proceedings of 19th International Conference on Nuclear Engineering (ICONE-19) (CD-ROM), 9 Pages, 2011/10

Free surface flow of a liquid metal Lithium (Li) is planned as a target irradiated by two deuteron beams to generate intense neutrons and it is thus important to obtain knowledge of the surface wave characteristic for the safety and the efficiency of system in the IFMIF. This paper reports the results of the wave height and the surface velocity examined experimentally using a Li loop at Osaka University and numerically using computational fluid dynamics (CFD) code, FLUENT. In the experiment, an electro-contact probe apparatus was used to obtain the wave height, and a high speed video was used to measure the surface velocity. A CFD simulation was also conducted to obtain information on the relation of the free surface with the inner flow. In the simulation, the model included from a two-staged contraction nozzle to a flow channel with a free surface flow region and simulation results were compared with the experimental data. We resulted in knowledge of the surface wave growth mechanism.

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.

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

Distinct structural requirements for interleukin-4 (IL-4) and IL-13 binding to the shared IL-13 receptor facilitate cellular tuning of cytokine responsiveness

Ito, Takachika*; Suzuki, Shoichi*; Kanaji, Sachiko*; Shiraishi, Hiroshi*; Ota, Shoichiro*; Arima, Kazuhiko*; Tanaka, Go*; Tamada, Taro; Honjo, Eijiro*; Garcia, K. C.*; et al.

Journal of Biological Chemistry, 284(36), p.24289 - 24296, 2009/09

 Times Cited Count:18 Percentile:59.46(Biochemistry & Molecular Biology)

Both IL-4 and IL-13 can bind to the shared receptor composed of the IL-4 receptor $$alpha$$ chain and the IL-13 receptor $$alpha$$-1 chain (IL-13R$$alpha$$1); however, the assembly mechanisms of these ligands to the receptor is different, enabling the principal functions of these ligands to be different. We have previously shown that the N-terminal Ig-like domain in IL-13R$$alpha$$1, called the D1 domain, is the specific and critical binding unit for IL-13. However, it has still remained obscure which the amino acid has specific binding capacity to IL-13 and why the D1 domain acts as the binding site for IL-13, but not IL-4. To address these questions, in this study, we performed the mutational analyses for the D1 domain, combining the structural data to identify the amino acids critical for binding to IL-13. Mutations of Lys76, Lys77, or Ile78 in c' strand in which the crystal structure showed interact with IL-13 and those of Trp65 and Ala79 adjacent to the interacting site, resulted in significant impairment of IL-13 binding, demonstrating that these amino acids generate the binding site. Furthermore, mutations of Val35, Leu38, or Val42 at N-terminal $$beta$$-strand also resulted in loss of IL-13 binding, probably from decrease structural stability. None of the mutations employed here affected IL-4 binding. These results demonstrate that the hydrophobic patch composed of Lys76, Lys77, and Ile78 is the IL-13 recognition site and solidify our understanding that the differential requirements of the D1 domain in IL-13R$$alpha$$1 allows the shared receptor to respond differentially to IL-4 and IL-13.

Journal Articles

Frequency comb spectroscopy for reliable evaluation of vibration characteristics of nuclear facilities by means of ACROSS, 2; Accurate measurements and monitoring

Nishida, Akemi; Suzuki, Yoshio; Hayashi, Sachiko; Kunitomo, Takahiro*; Kumazawa, Mineo*; Hasada, Yoko*

Dai-58-Kai Riron Oyo Rikigaku Koenkai Koen Rombunshu (CD-ROM), 2 Pages, 2009/06

ACROSS (Accurately Controlled, Routinely Operated, Signal System) is such a precise metrology of frequency response characteristics that the accurately controlled sinusoidal waves (acoustic comb) is used as an input to the linear dynamic system, and induced vibration as an output is measured by the accelerometers synchronized accurately to input. This technology has been developed to be used on a routine basis for the subsurface structural analysis and state-monitoring of the geological targets. We discuss the theoretical background and the related subjects of applying this method to the artificial structures. Further we report the preliminary test experiments and results on the steel beam structure installed at TGC, JAEA.

Journal Articles

Frequency comb spectroscopy for reliable evaluation of vibration characteristics of nuclear facilities by means of ACROSS, 3; Data processing method to estimate the vibration characteristics in multi-scales by means of SOMPI method

Nishida, Akemi; Suzuki, Yoshio; Hayashi, Sachiko; Kunitomo, Takahiro*; Kumazawa, Mineo*; Hasada, Yoko*

Dai-58-Kai Riron Oyo Rikigaku Koenkai Koen Rombunshu (CD-ROM), 2 Pages, 2009/06

The transfer function data in frequency domain acquired by ACROSS is analyzed by SOMPI method, which is based essentially on AR model as a discrete equivalent of linear dynamic system. The analysis is made in two steps, time domain analysis and space-wave number domain both in a consistent way as a linear dynamic system. We have derived an accurate set of vibration characteristics including attenuation and also the local characteristics such as wave propagation within the structural units and their interactions. Detection of small change in the structure is demonstrated by introduction of very precise measurement by ACROSS combined with the data analysis by SOMPI method.

Journal Articles

Frequency comb spectroscopy for reliable evaluation of vibration characteristics of nuclear facilities by means of ACROSS, 1; Basic line of approach for system identification and health monitoring

Nishida, Akemi; Suzuki, Yoshio; Hayashi, Sachiko; Kunitomo, Takahiro*; Kumazawa, Mineo*; Hasada, Yoko*

Dai-58-Kai Riron Oyo Rikigaku Koenkai Koen Rombunshu (CD-ROM), 2 Pages, 2009/06

Reliable and strict evaluation is demanded to guarantee the safety of nuclear facilities against earthquake vibrations, in particular. Usually the necessary data have been acquired by determining the natural frequency and attenuation characteristics by utilizing microseisms as an excitation agent of the vibration. The presence of measurement errors and estimation bias has been inherent and problematic in this approach. Here we try to make a break through by introducing ACROSS technology, which have been providing very accurate and reliable data on subsurface, i.e., geologic targets. In this paper, we report the relevant strategy, general concept of this approach. The technical subjects on measurement system and also a potential method of analyzing data are reported in the subsequent two papers.

Journal Articles

Development of cognitive methodology based data analysis system

Kino, Chiaki; Suzuki, Yoshio; Kushida, Noriyuki; Nishida, Akemi; Hayashi, Sachiko; Nakajima, Norihiro

High Performance Computing on Vector Systems 2008, p.89 - 97, 2009/00

In a field of research for nuclear power station, large and complex data analysis is an important issue. To overcome this issue, we have been developing Cognitive methodology based Data Analysis System (CDAS) in order to support researchers to analyze large and complex data. In the present study, we cleared up a structure of data analysis consisting of analysis target, evaluation index and judgment criteria. Additionally, we proposed some computational technologies to actualize CDAS. We have applied the system to the virtual plant vibration simulator and confirmed the implementability of this system.

Journal Articles

Development of three-dimensional virtual plant vibration simulator on grid computing environment ITBL-IS/AEGIS

Suzuki, Yoshio; Nishida, Akemi; Araya, Fumimasa; Kushida, Noriyuki; Akutsu, Taku; Teshima, Naoya; Nakajima, Kohei; Kondo, Makoto; Hayashi, Sachiko; Aoyagi, Tetsuo; et al.

Journal of Power and Energy Systems (Internet), 3(1), p.60 - 71, 2009/00

Center for computational science and e-systems of Japan Atomic Energy Agency is carrying out R&D in the area of extra large-scale simulation technologies for solving nuclear plant structures in its entirety. Specifically, we focus on establishing a virtual plant vibration simulator on inter-connected supercomputers intended for seismic response analysis of a whole nuclear plant. The simulation of a whole plant is a very difficult task because an extremely large dataset must be processed. To overcome this difficulty, we have proposed and implemented a necessary simulation framework and computing platform. The computing platform enables an extra large-scale whole nuclear plant simulation to be carried out on a grid computing platform ITBL-IS and AEGIS. The simulation framework based on the computing platform has been applied to a linear elastic analysis of the reactor pressure vessel and cooling systems of the nuclear research facility, HTTR.

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