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991.
Xing Hui GAO Hai Yun ZHOU . College of Mathematics Computer Science Yan’an University Shaanxi P. R. China . Department of Basic Courses Shijiazhuang Mechanical Engineering College Hebei 《数学研究与评论》2011,31(5)
The purpose of this article is to propose a shrinking projection method and prove a strong convergence theorem for a family of quasi-φ-strict asymptotically pseudo-contractions. Its results hold in reflexive, strictly convex, smooth Banach spaces with the property (K). The results of this paper improve and extend the results of Matsushita and Takahashi, Marino and Xu, Zhou and Gao and others. 相似文献
992.
This article studies the three-dimensional boundary layer flow of an elasticoviscous fluid over a stretching surface. Velocity
of the stretching sheet is assumed to be time-dependent. Effect of mass transfer with higher order chemical reaction is further
considered. Computations are made by the homptopy analysis method (HAM). Convergence of the obtained series solutions is explicitly
analyzed. Variations of embedding parameters on the velocity and concentration are graphically discussed. Numerical computations
of surface mass transfer are reported. Comparison of the present results with the numerical solutions is also given. 相似文献
993.
The effect of the Hall current on the magnetohydrodynamic (MHD) natural convection flow from a vertical permeable flat plate with a uniform heat flux is analyzed in the presence of a transverse magnetic field.It is assumed that the induced magnetic field is negligible compared with the imposed magnetic field.The boundary layer equations are reduced to a suitable form by employing the free variable formulation (FVF) and the stream function formulation (SFF).The parabolic equations obtained from FVF are numer... 相似文献
994.
The present investigation studies the peristaltic flow of the Jeffrey fluid through a tube of finite length. The fluid is electrically conducting in the presence of an applied magnetic field. Analysis is carried out under the assumption of long wavelength and low Reynolds number approximations. Expressions of the pressure gradient, volume flow rate, average volume flow rate, and local wall shear stress are obtained. The effects of relaxation time, retardation time, Hartman number on pressure, local wall she... 相似文献
995.
Numerical solutions of magnetodynamics(MHD) effects on the free convective flow of an incompressible viscous fluid past a moving semi-infinite vertical cylinder with temperature oscillation are presented.The dimensionless,unsteady,non-linear,and coupled governing partial differential equations are solved by using an implicit finite difference method of the Crank-Nicolson type.The velocity,temperature,and concentration profiles are studied for various parameters.The local skin-friction,the average skin-fr... 相似文献
996.
基于汽车与行人碰撞载荷特点的下肢长骨建模 总被引:1,自引:0,他引:1
基于THUMS(total human model for safety)下肢长骨有限元模型, 在材料和单元属性等方面进行了改进. 在详细分
析行人下肢长骨载荷特点的基础上, 采用多种不同载荷工况下较新的生物力学实
验数据, 对长骨模型进行了前-后和外-内加载
方向的准静态三点弯曲验证, 同时对近心端1/3处、中部和远心端1/3处加载的动态三点弯曲
验证. 验证结果表明, 该模型具有较好的生物逼真度, 能够准确地模拟行人下肢长骨的骨折
及碰撞响应, 可用于后续行人下肢模型的开发, 并为行人下肢损伤机理和安全防护研究提供
准确高效的研究手段. 相似文献
997.
Chun-Chuan Liu · Feng-Ming Li · Ting-Wei Liang · Wen-Hu Huang P.O.Box School of Astronautics Harbin Institute of Technology Harbin China 《Acta Mechanica Sinica》2011,27(5):785-795
In this paper,wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges are investigated using the wave approach.The dynamic responses,active and reactive power flow in the finite plate are calculated by the Mindlin plate theory (MPT) and classic plate theory (CPT).To satisfy the boundary conditions and continuous conditions at the coupled junction of the finite L-shaped plate,the near-field and far-field waves are entirely contained in the wave approach.The in-plane longitudinal and shear waves are also considered.The results indicate that the vibratory power flow based on the MPT is different from that based on the CPT not only at high frequencies but also at low and medium frequencies.The influence of the plate thickness on the vibrational power flow is investigated.From the results it is seen that the shear and rotary inertia correction of the MPT can influence the active and reactive power at the junction of the L-shaped plate not only at high frequencies but also at low and medium frequencies.Furthermore,the effects of structural damping on the active and reactive power flow at the junction are also analyzed. 相似文献
998.
Cementations formed in geological timescale are observed in various stiff clays.A micromechanical stress strain model is developed for modeling the effect of cementation on the deformation behavior of stiff clay.The proposed approach considers explicitly cementations at intercluster contacts,which is different from conventional model.The concept of inter-cluster bonding is introduced to account for an additional cohesion in shear sliding and a higher yield stress in normal compression.A damage law for inter-cluster bonding is proposed at cluster contacts for the debonding process during mechanical loading.The model is used to simulate numerous stress-path tests on Vallericca stiff clay.The applicability of the present model is evaluated through comparisons between the predicted and the measured results.In order to explain the stress-induced anisotropy arising from externally applied load,the evolution of local stresses and local strains at inter-cluster planes are discussed. 相似文献
999.
A.M.Zenkour 《Acta Mechanica Sinica》2011,27(6):956-962
The mixed first-order shear deformation plate theory(MFPT) is employed to study the bending response of simply-supported orthotropic plates.The present plate is subjected to a mechanical load and resting on Pasternak’s model or Winkler’s model of elastic foundation or without any elastic foundation.Several examples are presented to verify the accuracy of the present theory.Numerical results for deflection and stresses are presented.The proposed MFPT is shown simplely to implement and capable of giving satisfactory results for shear deformable plates under static loads and resting on two-parameter elastic foundation.The results presented here show that the characteristics of deflection and stresses are significantly influenced by the elastic foundation stiffness,plate aspect ratio and side-to-thickness ratio. 相似文献
1000.
Imperfect bonding between the constitutive components can greatly affect the properties of the composite structures.An asymptotic analysis of different types of imperfect interfaces arising in the problem of 2D fibrereinforced composite materials are proposed.The performed study is based on the asymptotic reduction of the governing biharmonic problem into two harmonic problems.All solutions are obtained in a closed analytical form.The obtained results can be used for the calculation of pull-out and pushout tests,as well as for the investigation of the fracture of composite materials. 相似文献