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FE FORMULATION FOR THE VISCOELASTIC BODY MODELED BY FRACTIONAL CONSTITUTIVE LAW

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Acta Mechanica Sinica 2001年第4期17卷 354-365页

作者：张卫 nobuyuki Shimizu Institute of Applied Mechanics Jinan UniversityGuangzhou 510632China Department of Mechanical Engineering Iwaki Meisei UniversityJapan

This paper presents finite element (FE) formulation of the viscoelastic materials described by fractional constitutive law. The time-domain three-dimensional constitutive equation is constructed. The FE equations are set up by treating the fractional operator as a special case of the hereditary integration. The equations are solved by numerical integration method. The numerical algorithm developed by the authors for Liouville-Riemann's fractional derivative was adopted to formulate FE procedures and extended to solve the more general case of the hereditary integration. The numerical examples were given to show the correctness and effectiveness of the integration algorithm.

关键词： viscoelasticity fractional calculus FEM polymer materials

Large Deformation Analysis and Synthesis of Elastic Closed-loop Mechanism Made of a Certain Spring Wire Described by Free Curves

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 756-762页

作者： IWATSUKI nobuyuki KOSAKI Takashi Department of Mechanical Sciences and Engineering Graduate School of Science and EngineeringTokyo Institute of Technology

Recently novel mechanisms with compact size and without many mechanical elements such as bearing are strongly required for medical devices such as surgical operation devices. This paper describes analysis and synthesis of elastic link mechanisms of a single spring beam which can be manufactured by NC coiling machines. These mechanisms are expected as disposable micro forceps. Smooth Curvature Model（SCM） with 3rd order Legendre polynomial curvature functions is applied to calculate large deformation of a curved cantilever beam by taking account of the balance between external and internal elastic forces and moments. SCM is then extended to analyze large deformation of a closed-loop curved elastic beam which is composed of multiple free curved beams. A closed-loop elastic link is divided into two free curved cantilever beams each of which is assumed as serially connected free curved cantilever beams described with SCM. The sets of coefficients of Legendre polynomials of SCM in all free curved cantilever beams are determined by taking account of the force and moment balance at connecting point where external input force is applied. The sets of coefficients of Legendre polynomials of a nonleaded closed-loop elastic link are optimized to design a link mechanism which can generate specified output motion due to input force applied at the assumed dividing point. For example, two planar micro grippers with a single pulling input force are analyzed and designed. The elastic deformation analyzed with proposed method agrees very well with that calculated with FEM. The designed micro gripper can generate the desired pinching motion. The proposed method can contribute to design compact and simple elastic mechanisms without high calculation costs.

关键词： elastic link mechanism closed-loop spring beam large deformation analysis smooth curvature model force balance equation synthesi

An Inverse Problem of Determining Coefficients in a One-Dimensional Radiative Transport Equation

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Advances in Applied Mathematics and Mechanics 2014年第4期6卷 515-522页

作者： nobuyuki Higashimori Faculty of Engineering Shibaura Institute of Technology307 FukakusaMinumaSaitamaJapan

We consider an inverse problem of determining unknown coefficients for a one-dimensional analogue of radiative transport *** show that some combination of the unknown coefficients can be uniquely determined by giving pulse-like inputs at the boundary and observing the corresponding *** result can be applied for determination of absorption and scattering properties of an optically turbid medium if the radiative transport equation is appropriate for describing the propagation of light in the medium.

关键词： Inverse problem radiative transport equation first-order hyperbolic system optical tomography

DISTRIBUTED WATER BALANCE WITH RIVER DYNAMIC-DIFFUSIVE FLOW ROUTING MODEL

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Journal of Hydrodynamics 2009年第4期21卷 564-572页

作者： HASSAN Ahmed NORIO Tanaka nobuyuki Tamai Graduate School of Science and Engineering Saitama University Graduate School Kanazawa Gakuin University

This article focuses on the application of coupling both river dynamic and river diffusive modeling techniques that can be used with distributed water balance model. In an upstream watershed, both overland and river diffusive flows are routed by diffusive wave approximation of the free surface flow equations. In river downstream reaches, the river dynamic flow is routed by one-dimensional dynamic wave equations （full dynamic St. Venant equations with lateral flow）. The developed model is applied in a part of Arakawa River basin, Kanto area, Japan. The geographic data of river cross sections could be accurately represented by an 11-point cross-section approximation. The effects of both the grid size and lateral flow on the simulated results of the river dynamic flow model were studied. The grid size should be greater than the average width of the river cross-sections. The lateral flow from small drainage systems has significant effects on the simulated results using the river dynamic flow model. The simulated results show good and acceptable agreements with the observed flow discharges and water depths. Both the river discharge and water depth at any location of river network of compound channels with one/two complex floodplains could be correctly estimated.

关键词： diffusive model dynamic model natural compound channels floodplains

DEM simulation of polydisperse systems of particles in a fluidized bed

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Particuology 2009年第1期7卷 9-18页

作者： nobuyuki Tagami Ajit Mujumdar Masayuki Horio Bio Applications and Systems Engineering Tokyo University of Agriculture & TechnologyNaka-choKoganei-shiTokyo 184-8588Japan

Numerical simulations based on three-dimensional discrete element model （DEM） are conducted for mono-disperse, binary and ternary systems of particles in a fluidized bed. Fluid drag force acting on each particle depending on its size and relative velocity is assigned. The drag coefficient corresponding to Ergun＇s correlation is applied to the system of fluidized bed with particle size ratios of 1：1 for the mono-disperse system, 1：1.2, 1：1.4 and 1：2 for the binary system and 1：1.33：2 for the ternary system by keeping total volume and surface area of the particles constant. Results indicated that a reasonable estimation of drag force based on individual particle diameters as compared to that of the mean diameter of the particles is achieved in the fluid cells. The total translational kinetic energy of the particles is found to increase as the particle size ratio increases, suggesting an enhanced momentum transfer in polydisperse particle systems. Systems with wide particle size distribution exhibited higher particle velocities around bubbles, resulting in faster bubble growth and its subsequent rise through the fluidized bed.

关键词： Discrete element method Fluid drag force Fluidized bed Particle size distribution

Growth of GaN/AlxGa1-xN (x=0.65) Superlattices on Si(111) Substrates Using RF-MBE

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Journal of Rare Earths 2006年第Z1期24卷 1-3页

作者： Armando S Somintac Tomo Kikuchi Michiya Odawara Takashi udagawa Motoi Wada Tadashi Ohachi Department of Electric Engineering Doshisha University 1-3 Miyakodani Tatara Kyotanabe Kyoto 610-0321 Japan Department of Electric Engineering Doshisha University 1-3 Miyakodani Tatara Kyotanabe Kyoto 610-0321 Japan Electronic Materials Division Electronics Section Showa Denko K.K. 1505 Shimokagemori Chichibu Saitama 369-1871 Japan Electronic Materials Division Electronics Section Showa Denko K.K. 1505 Shimokagemori Chichibu Saitama 369-1871 Japan Department of Electric Engineering Doshisha University 1-3 Miyakodani Tatara Kyotanabe Kyoto 610-0321 Japan Department of Electric Engineering Doshisha University 1-3 Miyakodani Tatara Kyotanabe Kyoto 610-0321 Japan

Superlattices with varying GaN well widths (2, 3, 6, 9 nm) and fixed AlGaN barrier (8 nm) with high Al-content (x=0.65) were grown. Streaky RHEED patterns indicated 2D growth mode for the superlattices. XRD measurements showed multiple satellite peaks corresponding to uniform periodicity of the GaN/AlGaN pairs. The AlGaN barrier XRD peak also shifted with increasing well widths, while the GaN XRD peak was nominally unchanged. Room temperature photoluminescence experiments revealed peak emissions at energies lower than the bulk GaN energy gap. The large red shift with respect to the bulk gap is attributed to significant Stark effect for wide multiple quantum wells.

关键词： molecular beam epitaxy superlattices GaN AlGaN built-in electric field stark effect

Protein-loosing enteropathy associated with rotavirus infection in an infant

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World Journal of Gastroenterology 2008年第10期14卷 1630-1632页

作者： Tadashi Iwasa nobuyuki Matsubayashi Department of Pediatrics Mie University Graduate School of Medicine Tsu Mie Japan Department of Pediatrics Shima Prefectural Hospital Shima Mie Japan

Rotavirus is an acute enteric pathogen in infants and children. We reported a rare case of a 6-mo-old infant with protein-loosing enteropathy (PLE) caused by rotavirus gastroenteritis, and evaluated the immunological profile in peripheral blood lymphocytes. Laboratory examinations showed lymphopenia, hypoproteinemia, hypoalbuminemia, hypogammaglobulinemia, and elevation of alpha-1-antitrypsin (α1-AT) clearance. Lymphocytes subpopulation study revealed the reversal of CD4+/CD8+ ratio with the selective decrease of CD4- positive lymphocytes. Moreover, the excessive increase of T cells producing IFN-gamma (IFN-γ) was found, which plays an important role in the protection against viral infection. The primary or secondary activation of immune system by rotavirus may influence structural integrity and vascular permeability, which may play a triggering role in protein-loosing enteropathy.

关键词： Protein-loosing enteropathy Rotavirus Lymphocytes producing IFN-γ Alpha-1-antitrypsin Reversal of CD4+/CD8+ ratio

Nuclear Planetology:Especially Concerning the Moon and Mars

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Research in Astronomy and Astrophysics 2012年第10期12卷 1313-1380页

作者： Kyeong Ja Kim nobuyuki Hasebe Korea Institute of Geoscience and Mineral Resources Daejeon305-350 Korea Research Institute for Science and Engineering Waseda UniversityShinjukuTokyo 169-8555 Japan

To approach basic scientific questions on the origin and evolution of plan- etary bodies such as planets, their satellites and asteroids, one needs data on their chemical composition. The measurements of gamma-rays, X-rays and neutrons emit- ted from their surface materials provide information on abundances of major elements and naturally radioactive gamma-ray emitters. Neutron spectroscopy can provide sen- sitive maps of hydrogen- and carbon-containing compounds, even if buried, and can uniquely identify layers of carbon-dioxide frost. Nuclear spectroscopy, as a means of compositional analysis, has been applied via orbital and lander spacecraft to extrater- restrial planetary bodies： the Moon, Venus, Mars, Mercury and asteroids. The knowl- edge of their chemical abundances, especially concerning the Moon and Mars, has greatly increased in recent years. This paper describes the principle of nuclear spec- troscopy, nuclear planetary instruments carried on planetary missions so far, and the nature of observational results and findings of the Moon and Mars, recently obtained by nuclear spectroscopy.

关键词： nuclear planetology: planetary remote sensing -- elemental mapping --nuclear science payloads -- chemical abundance

Influence of corneal power on circumpapillary retinal nerve fiber layer and optic nerve head measurements by spectral-domain optical coherence tomography

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International Journal of Ophthalmology(English edition) 2017年第9期10卷 1385-1391页

作者： Kazunori Hirasawa nobuyuki Shoji Department of Orthoptics and Visual Science School of Allied Health SciencesKitasato UniversitySagamiharaKanagawa 252-0373Japan Department of Ophthalmology School of medicineKitasato UniversitySagamiharaKanagawa 252-0373Japan

AIM：To evaluate the influence of corneal power on circumpapillary retinal nerve fiber layer（cp RNFL）and optic nerve head（ONH）measurements by spectral-domain optical coherence tomography（SD-OCT）.METHODS：Twenty-five eyes of 25 healthy participants（mean age 23.6±3.6y）were imaged by SD-OCT using horizontal raster *** soft contact lenses of different powers（from-11 to＋5 diopters including 0diopter）were worn to induce 2-diopter changes in corneal *** in the cp RNFL and ONH measurements per diopter of change in corneal power were ***：As corneal power increased by 1 diopter,total and quadrant cp RNFL thicknesses,except for the nasal sector,decreased by-0.19 to-0.32μm（P〈0.01）.Furthermore,the disc,cup,and rim areas decreased by-0.017,-0.007,and-0.015 mm2,respectively（P〈0.001）;the cup and rim volumes decreased by-0.0013 and-0.006 mm3,respectively（P〈0.01）;and the vertical and horizontal disc diameters decreased by-0.006 and-0.007 mm,respectively（P〈0.001）.CONCLUSION：For more precise OCT imaging,the ocular magnification should be corrected by considering both the axial length and corneal ***,the effect of corneal power changes on cp RNFL thickness and ONH topography are small when compare with those of the axial length.

关键词： optical coherence tomography ocularmagnification corneal power circumpapillary retinal nervefiber layer optic nerve head