Institution
Railway Technical Research Institute
Facility•Kokubunji, Japan•
About: Railway Technical Research Institute is a facility organization based out in Kokubunji, Japan. It is known for research contribution in the topics: Superconductivity & Superconducting magnet. The organization has 1377 authors who have published 1724 publications receiving 18322 citations. The organization is also known as: RTRI.
Papers published on a yearly basis
Papers
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TL;DR: A post-fabrication treatment is presented that improves the mechanical properties as well as thermal conductivity of a bulk Y-Ba-Cu-O magnet, thereby increasing its field-trapping capacity and thermal stability and internal mechanical strength.
Abstract: Large-grain high-temperature superconductors of the form RE-Ba-Cu-O (where RE is a rare-earth element) can trap magnetic fields of several tesla at low temperatures, and so can be used for permanent magnet applications. The magnitude of the trapped field is proportional to the critical current density and the volume of the superconductor. Various potential engineering applications for such magnets have emerged, and some have already been commercialized. However, the range of applications is limited by poor mechanical stability and low thermal conductivity of the bulk superconductors; RE-Ba-Cu-O magnets have been found to fracture during high-field activation, owing to magnetic pressure. Here we present a post-fabrication treatment that improves the mechanical properties as well as thermal conductivity of a bulk Y-Ba-Cu-O magnet, thereby increasing its field-trapping capacity. First, resin impregnation and wrapping the materials in carbon fibre improves the mechanical properties. Second, a small hole drilled into the centre of the magnet allows impregnation of Bi-Pb-Sn-Cd alloy into the superconductor and inclusion of an aluminium wire support, which results in a significant enhancement of thermal stability and internal mechanical strength. As a result, 17.24 T could be trapped, without fracturing, in a bulk Y-Ba-Cu-O sample of 2.65 cm diameter at 29 K.
831 citations
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TL;DR: In this article, the microstructural and superconducting properties of light rare earth elements (LREs) are reviewed and the flux pinning mechanism is also discussed, on the basis of their study over the last several years, the melt processes for LRE - Ba - Cu - O are described.
Abstract: Unlike Y123 which forms only a stoichiometric compound, the light rare earth elements (LREs: La, Nd, Sm, Eu, Gd) form a solid solution . The presence of such solid solution caused a depression in the superconducting transition temperatures , particularly for La123, Nd123 and Sm123 when they are melt processed in air. Recently, we have found that the of these LRE123 superconductors can greatly be enhanced when they are melt processed in a reduced oxygen atmosphere. Furthermore, values of these superconductors were larger than that of a good quality Y123 superconductor in high magnetic fields at 77 K. In this article, on the basis of our study over the last several years, the melt processes for LRE - Ba - Cu - O are described, the microstructural and superconducting properties of the superconductors are reviewed and the flux pinning mechanism is also discussed.
550 citations
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TL;DR: In this article, a method of simulating a class of nonstationary Gaussian random processes by passing a Gaussian white noise through a system introducing desirable nonstationarity at some phase of simulation is presented.
Abstract: A method is presented of simulating a class of nonstationary Gaussian random processes by passing a Gaussian white noise through a system introducing desirable nonstationarity at some phase of simulation. The method might have wide applications in stochastic mechanics such as in analysis of aircraft structures subjected to severe, random aerodynamic loading and in earthquake engineering. The relationship between the proposed nonstationary Gaussian process and the filtered Poisson process is examined in detail. Examples show that, if the convolution integrals, involved in the output of the system and also of the structure, can be avoided by particular choice of the impulse response functions, then a set of numerical simulations of the nonstationary process and the structural response can be performed rapidly on a computer.
306 citations
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Université catholique de Louvain1, James Hutton Institute2, Institut national de la recherche agronomique3, Tel Aviv University4, Washington State University5, Szent István University6, University of São Paulo7, Gembloux Agro-Bio Tech8, Aarhus University9, Railway Technical Research Institute10, Commonwealth Scientific and Industrial Research Organisation11, World Agroforestry Centre12, Swedish University of Agricultural Sciences13, Food and Agriculture Organization14
TL;DR: In this article, the authors describe the state of the art of soil spectroscopy as well as its potential to facilitate soil monitoring, and highlight that the widespread use of spectroscopes to monitor the status of the soil should be encouraged by the creation of a standard for the collection of laboratory soil spectra, to promote the sharing of spectral libraries, and to scan existing soil archives.
Abstract: The soil science community is facing a growing demand of regional, continental, and worldwide databases in order to monitor the status of the soil. However, the availability of such data is very scarce. Cost-effective tools to measure soil properties for large areas (e.g., Europe) are required. Soil spectroscopy has shown to be a fast, cost-effective, environmental-friendly, nondestructive, reproducible, and repeatable analytical technique. The main aim of this paper is to describe the state of the art of soil spectroscopy as well as its potential to facilitating soil monitoring. The factors constraining the application of soil spectroscopy as an alternative to traditional laboratory analyses, together with the limits of the technique, are addressed. The paper also highlights that the widespread use of spectroscopy to monitor the status of the soil should be encouraged by (1) the creation of a standard for the collection of laboratory soil spectra, to promote the sharing of spectral libraries, and (2) the scanning of existing soil archives, reducing the need for costly sampling campaigns. Finally, routine soil analysis using soil spectroscopy would be beneficial for the end users by a reduction in analytical costs, and an increased comparability of results between laboratories. This ambitious project will materialize only through (1) the establishment of local and regional partnerships among existent institutions able to generate the necessary technical competence, and (2) the support of international organizations. The Food and Agriculture Organization (FAO) of United Nations and the Joint Research Centre of the European Commission are well placed to promote the use of laboratory and field spectrometers for monitoring the state of soils.
305 citations
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TL;DR: In this paper, an outline of the shield tunnel technique at present, behavior of shield tunnels in-site, and improvements required for design are presented. But, due to the well-balanced progress between construction and design, an innovation of the design technique is required.
275 citations
Authors
Showing all 1378 results
Name | H-index | Papers | Citations |
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Hiroyuki Sasaki | 73 | 236 | 21800 |
Makoto Ishida | 40 | 526 | 5811 |
Atsushi Ishihara | 35 | 262 | 6078 |
Hiroyuki Fujimoto | 33 | 202 | 3787 |
Yasuhiro Iijima | 33 | 273 | 4759 |
Miryala Muralidhar | 29 | 249 | 3189 |
Naomichi Sakai | 29 | 172 | 4113 |
Sang-Im Yoo | 28 | 176 | 4152 |
Naoki Koshizuka | 26 | 320 | 3377 |
Masataka Iwakuma | 24 | 259 | 2582 |
Kazuomi Kakimoto | 23 | 102 | 1435 |
Kazuhide Kimbara | 23 | 31 | 2159 |
Noriko Chikumoto | 22 | 122 | 1838 |
Takamitsu Higuchi | 22 | 84 | 2904 |
Milos Jirsa | 22 | 124 | 1487 |