Nishimura S.,Kobe City College of Technology
Journal of the Physical Society of Japan | Year: 2015
On the basis of a kinetic energy principle, it is shown that the interchange mode in helical systems is excited by trapped energetic ions, where the ideal interchange mode is stable. The mode has a rotation frequency comparable to precession drift frequencies of trapped energetic ions. The theory explains how to apply the fishbone mode theory originally developed in tokamaks to helical systems. ©2015 The Physical Society of Japan.
Ogiwara A.,Kobe City College of Technology |
Watanabe M.,University of Shizuoka
Applied Optics | Year: 2012
Holographic polymer dispersed liquid crystal (HPDLC) memory is fabricated by a photoinduced phase separation comprised of polymer and liquid crystal (LC) phases using laser light interference exposures. The anisotropic diffraction induced by the alignment of LC in the periodic structure of the HPDLC memory is applied to reconstruct the configuration contexts for the optically reconfigurable gate arrays. Optical reconfiguration for various circuits under parallel programmability is implemented by switching the polarization state of incident light on the HPDLC memory using a spatial light modulator. © 2012 Optical Society of America.
Uenaka K.,Kobe City College of Technology |
Kitoh H.,Osaka City University
Thin-Walled Structures | Year: 2011
Concrete filled double skin circular tubular member (CFDST) has a hollowed section consisting of double concentric steel tubes with concrete fill in between their walls. The CFDST members are consequently lighter than ordinary concrete filled tubular members (CFT) which have solid sections. The purpose of this study is to investigate the mechanical behavior of CFDST deep beam under a combined action of shear and bending through a three points static loading test. Two testing parameters were considered, namely, the inner-to-outer diameter ratio (D i/D o) and the outer tube diameter-to-thickness ratio (D o/t o). The results showed that the obtained failure modes were controlled by the parameter D i/D o. Their strengths for ratios of less than 0.47 fairly agreed with the estimation values proposed herein. Furthermore, biaxial elasto-plastic stress histories of both tubes under plane stress condition were also discussed. © 2010 Elsevier Ltd. All rights reserved.
Uenaka K.,Kobe City College of Technology
Journal of Constructional Steel Research | Year: 2016
Concrete filled double skin steel tubular (CFDST) members, having a hollow section consisting of two concentric steel tubes and filled concrete between the two walls of the tubes, are lighter than the ordinary concrete filled steel tubular (CFT) members, which have solid cross-sections. Therefore, the CFDST members can work effectively as seismic resistant structures such as bridges high piers during earthquake. The present study aims to investigate experimentally centric loading characteristics of the CFDST stub column consisting of an outer circular steel tube and an inner square steel tube with in-filled concrete between the double walls, which are abbreviated as CS-CFDST. The two selected testing parameters are the outer tube's diameter-to-thickness ratio and inner width to outer diameter ratio. From the results, observed failure modes were divided into two groups: local buckling associated with shear failure of in-filled concrete and local buckling of the double tubes. These failure modes were affected by inner width to outer diameter ratio. Axial load capacities were also determined by the above described failure modes. Additionally, elasto-plastic biaxial stress behavior of both tubes under plane stress condition is also mentioned. Methods to predict the axial load capacities of CS-CFDST stub columns are also provided. © 2015 Elsevier Ltd. All rights reserved.
Ogiwara A.,Kobe City College of Technology
Applied Optics | Year: 2011
Volume gratings fabricated by interferometric exposure using composite materials composed of nematic liquid crystals (LC) and LC diacrylate monomers are discussed in the effects of diffraction properties on different grating formations, such as varying LC content ratios, film thicknesses, and the surface conditions composed of alignment layers and rubbing directions. Diffraction properties are experimentally investigated in the viewpoints of anisotropic diffraction and LC orientation. The polarization-azimuth dependence of diffraction efficiencies as functions of the incident polarization states shows the controllability of anisotropic diffractions based on the effects of different surface conditions. © 2011 Optical Society of America.