著者
Sakakibara Jun Machida Nobuteru
出版者
American Institute of Physics
雑誌
Physics of fluids (ISSN:10706631)
巻号頁・発行日
vol.24, no.4, pp.041702, 2012-04
被引用文献数
32 9

We measured velocity distribution in cross sections of a fully developed turbulentpipe flow upstream and downstream of a 90◦ bend by synchronizing two sets ofa particle image velocimetry (PIV) system. Unsteady undulation of Dean vorticesformed downstream from the bend was characterized by the azimuthal position ofthe stagnation point found on the inner and outer sides of the bend. Linear stochasticestimationwas applied to capture the upstream flowfield conditioned by the azimuthallocation of the stagnation point downstream from the bend. When the inner-sidestagnation point stayed below(above) the symmetry plane, the conditional streamwisevelocity upstream from the bend exhibited high-speed streaks extended in a quasistreamwisedirection on the outer side of the curvature above (below) the symmetryplane.
著者
Ito T. Katanuma I.
出版者
American Institute of Physics
雑誌
Physics of Plasmas (ISSN:1070664X)
巻号頁・発行日
vol.12, no.8, pp.082512, 2005-08-16
被引用文献数
5 4

The neoclassical resonant plateau transport in a mirror cell is studied theoretically. The analytical expression for a non-square-well magnetic field is obtained. The analytical result is applied to the GAMMA10 tandem mirror [T. Cho, M. Yoshida, J. Kohagura et al., Phys. Rev. Lett. 94, 085002-1 (2005)], which consists of several mirror cells in it, and the confinement time due to the neoclassical resonant plateau transport is determined in each mirror cell. It is found that the neoclassical resonant transport of ions trapped in the nonaxisymmetric anchor mirror cell and transition mirror cells is significantly smaller than those trapped in the central cell.
著者
Sasagawa Y. Katanuma I. Mizoguchi Y. Cho T. Pastukhov V. P.
出版者
American Institute of Physics
雑誌
Physics of Plasmas (ISSN:1070664X)
巻号頁・発行日
vol.13, no.12, pp.122506, 2006-12-18
被引用文献数
9 9

Magnetohydrodynamic stabilization of an axisymmetric mirror plasma with a magnetic divertor is studied. An equation is found for the flute modes, which includes the stabilizing influence of ion temperature anisotropy and nonparaxial magnetic fields, as well as a finite ion Larmor radius. It is shown that if the density profile is sufficiently gentle, then the nonparaxial configuration can stabilize all modes as long as ion temperature is radially uniform. This can be demonstrated even when the density vanishes on the separatrix and even for small ion Larmor radii. It is found, however, that the ion temperature gradient makes the unstable region wider; high ion temperature is required to stabilize the flute mode.
著者
Katanuma I. Yagi K. Nakashima Y. Ichimura M. Imai T.
出版者
American Institute of Physics
雑誌
Physics of Plasmas (ISSN:1070664X)
巻号頁・発行日
vol.17, no.3, pp.032303, 2010-03
被引用文献数
8 7

The computer code by reduced magnetohydrodynamic equations were made which can simulate the flute interchange modes (similar to the Rayleigh–Taylor instability) and the instability associated with the presence of nonuniform plasma flows (similar to the Kelvin–Helmholtz instability). This code is applied to a model divertor and the GAMMA10 [ M. Inutake et al., Phys. Rev. Lett. 55, 939 (1985) ] with divertor in order to investigate the flute modes in these divertor cells. The linear growth rate of the flute instability determined by the nonlocal linear analysis agrees with that in the linear phase of the simulations. There is a stable nonlinear steady state in both divertor cells, but the nonlinear steady state is different between the model divertor and the GAMMA10 with divertor.
著者
Katanuma I. Yagi K. Haraguchi Y. Ichioka N. Masaki S. Ichimura M. Imai T.
出版者
American Institute of Physics
雑誌
Physics of plasmas (ISSN:1070664X)
巻号頁・発行日
vol.17, no.11, pp.112506, 2010-11
被引用文献数
8 7

The flute instability and the associated radial transport are investigated in the tandem mirror with a divertor mirror cell (the GAMMA10 A-divertor) with help of computer simulation, where GAMMA10 is introduced [ Inutake et al., Phys. Rev. Lett. 55, 939 (1985) ]. The basic equations used in the simulation were derived on the assumption of an axisymmetric magnetic field. So the high plasma pressure in a nonaxisymmetric minimum-B anchor mirror cell, which is important for the flute mode stability, is taken into account by redefining the specific volume of a magnetic field line. It is found that the flute modes are stabilized by the minimum-B magnetic field even with a divertor mirror although its stabilizing effects are weaker than that without the divertor mirror. The flute instability enhances the radial transport by intermittently repeating the growing up and down of the Fourier amplitude of the flute instability in time.
著者
石倉 恵介 宮川 俊平 矢田部 佳久 竹越 一博 大森 肇
出版者
日本体力医学会
雑誌
体力科學 (Japanese journal of physical fitness and sports medicine) (ISSN:0039906X)
巻号頁・発行日
vol.57, no.4, pp.475-484, 2008-08

To determine the effect of taurine on blood glucose concentration during prolonged exercise, fifteen male university students cycled for 120 min at 50%VO2max after 7 days with or without taurine supplementation. Exercise tended to reduce the blood glucose concentration, whereas taurine significantly prevented this decline. Exercise significantly increased plasma glucagon concentrations in both groups to a similar degree. Serum insulin concentrations did not differ during exercise under both conditions. Taurine supplementation respectively significantly inhibited and tended to inhibit the plasma noradrenaline and adrenaline concentrations increased by exercise. These results suggest that taurine supplementation can maintain the blood glucose concentration during prolonged exercise through enhanced catecholamine sensitivity.
著者
Kakeya Hideki Sawada Shimpei
出版者
Society of Photo-optical Instrumentation Engineers
雑誌
Proc. SPIE, Three-Dimensional Imaging, Visualization (ISSN:0277786X)
巻号頁・発行日
vol.8043, pp.80430B, 2011

In this paper realization of precise depth perception using coarse integral volumetric imaging (CIVI) is discussed. CIVI is a 3D display technology that combines multiview and volumetric solutions by introducing multilayered structure to integral imaging. Since CIVI generates real images optically, optical distortion can cause distortion of 3D space to be presented. To attain presentation of undistorted 3D space with CIVI, the authors simulate the optics of CIVI and propose an algorithm to show undistorted 3D space by compensating the optical distortion on the software basis. The authors also carry out psychophysical experiments to verify that vergence-accommdation conflict is reduced and depth perception of the viewer is improved by combining multiview and volumetric technologies.
著者
Sawada Shimpei Kakeya Hideki
出版者
Society of Photo-optical Instrumentation Engineers
雑誌
Proc. SPIE, Stereoscopic Displays and Applications XXII (ISSN:0277786X)
巻号頁・発行日
vol.7863, pp.78631L, 2011
被引用文献数
2

Coarse integral volumetric imaging (CIVI) combines multiview and volumetric display solutions and presents undistorted floating 3D image by correcting distortion of volumetric image for each view. In the conventional CIVI with limited viewing angle, distortions of image planes can be approximated to be parabolic in the direction of depth, while those in horizontal and vertical directions can be ignored. When the viewing angle becomes wider, however, this approximation cannot realize presentation of undistorted image. To cope with the strong distortions, the method the authors propose calculate z-coordinate of the generated real image is in detail and depicts each pixel on the display panel of the corresponding depth. Also distortions in horizontal and vertical directions are corrected by using texture mapping. To attain precise correction in vertical, horizontal and depth directions, optical paths of light rays between the display panel and each viewpoint are calculated with an optical simulator. Color aberration can also be corrected by mapping red, green and blue textures separately based on the result of the optical simulation.
著者
Kurokawa Tomoya Kakeya Hideki
出版者
Society of Photo-optical Instrumentation Engineers
雑誌
Proc. SPIE, Stereoscopic Displays and Applications XXII (ISSN:0277786X)
巻号頁・発行日
vol.7863, pp.78631M, 2011
被引用文献数
3

Coarse integral imaging (CII), where each elemental lens is large enough to cover pixels far more than the number of views, can show clear floating 3D image when distortion is corrected. One of the major problems left to be solved for CII is suppression of pseudo images that appear around the right image to be presented. In this paper we propose two methods to suppress pseudo images. We first propose use of a lens array with a small F number. When a lens array composed of elemental lenses whose F number is small is set in front of the display panel, pseudo images can be erased by total internal reflection on the outskirt of the large aperture lens because the angle of incidence of the light ray that generates pseudo images becomes larger. The second method we propose is use of a lens array behind the display panel paired with segmented backlight. When convex lenses are set in front of the backlight with limited aperture, leak of ray out to adjacent elemental lenses can be avoided. Since the backlight area is reduced, this method can also reduce consumption of electric power without diminishing brightness of the right image.
著者
平野 圭一 島谷 民夫 小野 泰三 河田 哲郎 黒石 範彦 山田 想 宮川 宣明 深瀬 政秋 相原 玲二 栗野 浩之 小柳 光正
出版者
一般社団法人電子情報通信学会
雑誌
電子情報通信学会技術研究報告. VLD, VLSI設計技術
巻号頁・発行日
vol.97, no.577, pp.47-54, 1998-03-06

モンテカルロ法による半導体素子シミュレーションは、ゲート長0.1μm以下の極微細半導体素子におけるホットキャリア効果などの物理現象の解析に非常に有用である。しかしながら、モンテカルロ法による半導体素子シミュレーションは、その精度を向上させるために、非常に多くの電子や正孔を追跡する必要があり、計算時間が膨大になるという欠点を持っている。そこで、この計算時間を大幅に減少するため、我々はモンテカルロ法による半導体素子シミュレーション専用のマイクロプロセッサを設計・試作し、これを用いた専用並列計算機を開発した。この専用並列計算機を用いて実際に極微細半導体素子のシミュレーションを行い、正常な結果が得られることを確認した。
著者
加藤 耕一
出版者
東京理科大学
雑誌
若手研究(B)
巻号頁・発行日
2003

本研究は、農村舞台の保存・活用の実態調査およびその方策を示すことを目的としている。今年度は、3ヵ年計画の初年に当たり、農村舞台の保存・活用に関する基礎調査を中心課題とした。基礎調査は、舞台建築の実測調査および使われ方のヒアリング調査からなり、調査対象地域としては、徳島県を中心としているが、舞台形式に関連性のみられる淡路島(兵庫県)を補足的に踏査した。調査の結果、徳島県に農村舞台が112棟現存していることを確認した。加えて、舞台機構または舞台装置の仕掛けに関して重要と思われる農村舞台(今山、小祖谷、拝宮、府殿、法市)については、復原のための実測および痕跡調査を行い、小祖谷と法市の両舞台が仮設舟底舞台形式(多目的な平舞台から人形芝居専用の舞台形式である舟底舞台へと転換する舞台形式)であることを明らかにした。また、これらの農村舞台調査と並行して、「小屋掛け舞台」と呼ばれる仮設式の舞台を調査した。小屋掛け舞台は吉野川流域および淡路島に分布しており、悉皆的調査には及んでいないが、比較的保存状態のよい小屋掛け舞台の部材を実測し、痕跡調査と併せて組立て方法の聞き取りを行い、小屋掛け舞台の構造および仮設工法を明らかにした。本研究では、地域の人々との共同作業を通して、地域から人的組織を掘り起こし、活用支援のための人的ネットワークをつくることを基本理念としている。平成15年度は、研究者・建築家などの専門家や一般市民らとともに、農村舞台活用支援団体「阿波農村舞台の会」の設立に参加し、組織的に農村舞台調査、保存・活用方法の検討、支援活動をはじめた。平成15年9月22日に復活公演を催した法市農村舞台では、調査および住民への調査報告・説明会を本研究により行い、舞台の修復・復原や公演企画などの作業を、地域住民と阿波農村舞台の会、教育委員会との連携で取り組んだ。
著者
持田 諒 三宅 茜巳
出版者
岐阜女子大学
雑誌
基盤研究(C)
巻号頁・発行日
2006

岐阜県には地歌舞伎保存会が28座ある。研究代表者は、30年に亘る人間国宝を中心とした歌舞伎・文楽等伝統芸能の舞台監督体験を踏まえ、地芝居及び芝居小屋の現状調査を2006年から2008年の3年次に亘って実施した。又、それらを支える技術職人が数年にして他界していくことも痛感、一人の職人に秘められた時代層も同時に消滅することを痛感した。調査に当たっては古老の聞き書き、映像収録を重視し後世の生きた教材とした。又、未調査の〓殿型農村舞台の撮影、実測も実施した。
著者
安田 徳子
出版者
岐阜聖徳学園大学
雑誌
基盤研究(C)
巻号頁・発行日
2010

各地の地芝居に伝承された古台本はそれぞれの歴史と特徴をよく伝えているので、本研究では、出羽・赤城山麓・伊那谷・東濃・三河・小豆島の地芝居を対象として古台本の調査を行い、ほとんどの地芝居が江戸時代後期から明治初期までに上方系の旅役者によって伝えられたこと、その後も旅役者が地芝居に濃密に関わってきたことが明らかとなった。江戸系の台本も多少はあるが、明治以降の流入である。地芝居は義太夫芝居の奉納が根底で、浄瑠璃本を台本として伝える地域も多い。