FINITE VOLUME METHOD BASED ON THE CROUZEIX-RAVIART ELEMENT FOR THE STOKES EQUATION

ＩＮＴＲＯＤＵＣＴＩＯＮＷｅｃｏｎｓｉｄｅｒｔｈｅＳｔｏｋｅｓｅｑｕａｔｉｏｎ :-Δ ｕ ｐ = ｆ　ｉｎΩ ( 1 )ｄｉｖ ｕ =0　ｉｎΩ ( 2 ) ｕ =0　ｏｎ Ωｗｈｅｒｅ ｕ =(ｕ1 ,ｕ2 ) Ｔａｎｄｐｄｅｎｏｔｅｔｈｅｖｅｌｏｃｉｔｙａｎｄｔｈｅｐｒｅｓｓｕｒｅｏｆｔｈｅｆｌｕｉｄｒｅｓｐｅｃｔｉｖｅｌｙ . ｆｄｅ ｎｏｔｅｓｔｈｅｅｘｔｅｒｎａｌｂｏｄｙｆｏｒｃｉｎｇｄｅｎｓｉｔｙ.Ωｉｓａｎｏｐｅｎｂｏｕｎｄｅｄａｎｄｃｏｎｖｅｘｐｏｌｙｇｏｎａｌｄｏｍａｉｎ . Ωｄｅｎｏｔｅｓｔｈｅｂｏｕｎｄａｒｙｏｆ…     

Properties of High Strength Steel Fiber Reinforced Concrete under Compression

ＰｒｏｐｅｒｔｉｅｓｏｆＨｉｇｈＳｔｒｅｎｇｔｈＳｔｅｅｌＦｉｂｅｒＲｅｉｎｆｏｒｃｅｄＣｏｎｃｒｅｔｅｕｎｄｅｒＣｏｍｐｒｅｓｓｉｏｎＱｉａｎＣｈｕｎｘｉａｎｇ（钱春香）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅ...     

Using Neural Network to Predict the Interfacial Friction and Flow Stress of Materialsvia Ring Compre

ＵｓｉｎｇＮｅｕｒａｌＮｅｔｗｏｒｋｔｏＰｒｅｄｉｃｔｔｈｅＩｎｔｅｒｆａｃｉａｌＦｒｉｃｔｉｏｎａｎｄＦｌｏｗＳｔｒｅｓｓｏｆＭａｔｅｒｉａｌｓｖｉａＲｉｎｇＣｏｍｐｒｅｓｓｉｏｎＸｕＷｅｉｌｉａｎｇ（徐卫良）（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａ...     

第二代小波应用于图象的无损压缩编码

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｔｈｅｉｍａｇｅｌｏｓｓｌｅｓｓｃｏｍｐｒｅｓｓｉｏｎｃｏｄｉｎｇｉｓａｎｉｍｐｏｒｔａｎｔｐａｒｔｏｆｔｈｅｄｉｇｉｔａｌｉｍａｇｅｃｏｍｐｒｅｓｓｉｏｎｒｅｓｅａｒｃｈ .Ｍｅｄｉｃａｌｉｍａｇｅｓ,ｓａｔｅｌｌｉｔｅｉｍａｇｅｓａｎｄｓｅｉｓｍｉｃｄａｔａｄｅｍａｎｄｌｏｓｓ ｌｅｓｓｃｏｄｉｎｇ .Ｔｈｅｂａｓｉｃｉｄｅａｏｆｃｏｍｐｒｅｓｓｉｏｎｉｓｔｏｅｘｐｌｏｉｔｔｈｅｃｏｒｒｅｌａｔｉｏｎｓｔｒｕｃｔｕｒｅｐｒｅｓｅｎｔｅｄｉｎｍｏｓｔｒｅａｌｌｉｆｅｉｍ …     

RESEARCH ON THE CONTINUOUS POSITIONING CONTROL TO SERVO-PNEUMATIC SYSTEM

ＩＮＴＲＯＤＵＣＴＩＯＮＳｅｒｖｏ ｐｎｅｕｍａｔｉｃｓｙｓｔｅｍｓｈａｖｅｂｅｅｎｓｔｕｄｉｅｄｓｉｎｃｅｔｈｅ 1 950’ｓ.Ｄｕｅｔｏｔｈｅｉｒｎａｔｕｒａｌｃｈａｒａｃｔｅｒ ｉｓｔｉｃｓｏｆａｉｒｃｏｍｐｒｅｓｓｉｂｉｌｉｔｙ ,ｐｏｏｒｄａｍｐｉｎｇａｂｉｌｉ ｔｙ ,ｓｉｇｎｉｆｉｃａｎｔｍｅｃｈａｎｉｃａｌｆｒｉｃｔｉｏｎ ,ａｎｄｓｔｒｏｎｇｎｏｎｌｉｎｅａｒｉｔｉｅｓ,ｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｗａｓｒｅｓｔｒｉｃｔｅｄ .Ｗｉｔｈｔｈｅｒａｐｉｄｄｅｖｅｌｏｐｍｅｎｔｉｎｔｈｅｆｉｅ…     

Adaptive Lagrange finite element methods for high precision vibrations and piezoelectric acoustic wave computations in SMT structures and plates with nano interfaces

ＩＮＴＲＯＤＵＣＴＩＯＮＡｓｗｅｋｎｏｗ ,ｔｈｅｃｏｍｐｕｔａｔｉｏｎａｌｐｉｅｚｏｅｌｅｃｔｒｉｃｄｙｎａｍｉｃｅｑｕａｔｉｏｎｓｆｏｒｈｉｇｈｆｒｅｑｕｅｎｃｙａｃｏｕｓｔｉｃｗａｖｅｐｒｏｐａｇａｔｉｏｎｓｗｅｒｅｏｒｉｇｉｎａｌｌｙｅｘｐａｎｄｅｄｆｒｏｍｔｈｅｇｅｎｅｒａｌｃｏｍｐｕｔａｔｉｏｎａｌｓｔｒｕｃｔｕｒａｌｍｅｃｈａｎｉｃｓ,ａｎｄｔｈｅｆｉｎｉｔｅｅｌｅｍｅｎｔｍｅｔｈｏｄｓ(ＦＥＭ)ｉｎｉｔｉａｌｌｙｆｒｏｍａｅｒｏｓｐａｃｅａｎｄｃｉｖｉｌｅｎｇｉｎｅｅｒｉｎｇ .Ｔｈｅ…     

Large eddy simulation of a particle-laden turbulent plane jet

ＩＮＴＲＯＤＵＣＴＩＯＮＭａｎｙｅｘｐｅｒｉｍｅｎｔａｌａｎｄｎｕｍｅｒｉｃａｌｓｔｕｄｉｅｓｈａｖｅｂｅｅｎｃｏｍｐｌｅｔｅｄｔｏｉｎｖｅｓｔｉｇａｔｅｔｈｅｐａｒｔｉｃｌｅｍｏｔｉｏｎｉｎｔｕｒｂｕｌｅｎｃｅ .Ｐｒｅｖｉｏｕｓｆｌｕｉｄｄｙｎａｍｉｃｓｓｔｕｄｉｅｓｗｅｒｅｃｏｍｍｏｎｌｙｂａｓｅｄｏｎｔｉｍｅ ａｖｅｒａｇｅｄＲｅｙｎｏｌｄｓｅｑｕａｔｉｏｎｓ,ｓｕｃｈａｓｔｈｅｔｗｏ ｅｑｕａｔｉｏｎｍｏｄｅｌ.Ｊｕｓｔｌｉｋｅｔｈｅｃａｒｒｉｅｒｇａｓｐｈａｓｅ,ｔｈｅｐａｒｔｉ ｃｌｅｐｈ…     

GENERAL CONTENTS (Vol.5,2 0 0 1 )

·Ｒｅｖｉｅｗｓ·ＯｎｔｈｅＩｎｔｅｒａｃｔｉｏｎｓｏｆＭｉｃｒｏｗａｖｅｗｉｔｈＬｉｇｈｔｗａｖｅ ＸＵＤｅ ｍｉｎｇ　ＺＨＯＵＳｈｉ ｐｉｎｇ　 ( 1 )………………………………·Ｌｅｔｔｅｒｓ·ＡＮｅｗＥｌａｓｔｉｃｉｔｙａｎｄＦｉｎｉｔｅＥｌｅｍｅｎｔＦｏｒｍｕｌａｔｉｏｎｆｏｒＤｉｆｆｅｒｅｎｔＹｏｕｎｇ’ｓＭｏｄｕｌｕｓｗｈｅｎＴｅｎｓｉｏｎａｎｄＣｏｍｐｒｅｓｓｉｏｎＬｏａｄｉｎｇｓ ＹＥＺｈｉ ｍｉｎｇ　ＹＵＨｕａｎ ｒａｎ　ＹＡＯＷｅｎ ｊｕａｎ　 (89)……………………………ＢｒｉｅｆＩｎ…     

A New Elasticity and Finite Element Formulation for Different Young''''s Modulus When Tension and Compression Loadings

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｗｉｔｈｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｎｅｗｍａｔｅｒｉａｌｓ ,ｉｔｈａｓｂｅｅｎｓｈｏｗｎｔｈｅｍｏｓｔｏｆｔｈｅｍｈａｄｔｈｅｄｉｆｆｅｒｅｎｔｍｅｃｈａｎｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ,ｔｈａｔｉｓｔｈｅｄｉｆｆｅｒｅｎｔＹｏｕｎｇ’ｓｍｏｄｕｌｕｓ ,ｗｈｅｎｔｅｎｓｉｏｎａｎｄｃｏｍｐｒｅｓｓｉｏｎｌｏａｄｉｎｇｓ.Ａｌａｒｇｅｎｕｍ ｂｅｒｓｏｆｔｈｅｅｘｐｅｒｉｍｅｎｔａｌｄａｔａｃｏｕｌｄｂｅｓｈｏｗｎｔｈｅｃｏｎ ｓｔｉｔｕｔｉｖｅｒｅｌａｔｉ…     

碘、溴和叠氮化物水溶液中的声化学反应

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｔｈｅｃｈｅｍｉｃａｌｅｆｆｅｃｔｓｏｆｕｌｔｒａｓｏｕｎｄａｒｅｄｕｅｔｏｈｉｇｈｐｒｅｓｓｕｒｅｐｒｏｄｕｃｅｄｄｕｒｉｎｇｖｉｏｌｅｎｔｃｏｌｌａｐｓｅｏｆｃａｖｉｔａｔｉｏｎｂｕｂｂｌｅｓ.Ｔｈｅｒｅａｃｔｉｏｎｓｄｏｎｏｔｔａｋｅ ｐｌａｃｅｈｏｍｏｇｅ ｎｅｏｕｓｌｙｉｎｔｈｅｓｏｌｕｔｉｏｎｂｕｔｉｎ”ｈｏｔｓｐｏｔｓ”ｗｈｅｒｅｃａｖｉ ｔａｔｉｏｎｂｕｂｂｌｅｓｐｕｌｓａｔｅｏｒｃｏｌｌａｐｓｅ .Ｄｕｒｉｎｇｔｈｅａｄｉａｂａｔ ｉｃｃｏｍｐｒｅｓｓｉｏ…     

考虑剪切效应弹性板弯曲问题的DQ分析方法

A differential quadrature (DQ) method for orthotropic plates was proposed based on Reddy' s theory of plates with the effects of the higher-order transverse shear deformations. Wang-Bert's DQ approach was also further extended to handle the boundary conditions of plates. The computational convergence was studied, and the numerical results were obtained for different grid spacings and compared with the existing results. The results show that the DQ method is fairly reliable and effective.     

基于变域变分有限元的翼型气动设计

Designing airfoils according to given pressure (or velocity) distribution is one kind of free boundary problems. Free boundary condition can be coupled with the flow governing equations by variable-domain variational calculus, which makes it possible to calculate simultaneously the flow field and the free boundary. An accurate deduction of the variable-domain variational principles is taken herein to design airfoils in compressible and incompressible flows. Furthermore, two grid types (H and O) are used in the calculation with better results for the O-type grid. It is shown that convergence is accelerated and good results can be obtained even if the initial guessed airfoil shape is a triangle, demonstrating the strong adaptability of this method.     

一个八阶收敛的修正牛顿法

给出了一个求解非线性方程的新算法,并证明了它具有八阶收敛速度。同时给出数值试验,通过与牛顿法及其他算法比较,说明了新算法具有一定的优越性。     

n次方根的近似解

n次方根nm可转化为方程xn-m=0的实根,本文给出了求n次方根的四种近似解法:二分法、迭代法、牛顿法和弦截法,并通过数值例子比较它们的收敛速度。     

H-矩阵的预条件Gauss-Seidel迭代法收敛性

H-矩阵是一类用途广泛的矩阵.当线性系统的系数矩阵为H-矩阵时,在更广义的分裂条件下,运用Gauss-Seidel迭代法解线性系统,得到了在一类预条件矩阵下的收敛结果.最后给出数值例子验证了此结论.     

预条件AOR迭代法比较性定理

在预条件矩阵(I+S+R)下提出新的AOR迭代法,讨论了新方法的敛散性,并给出了新预条件AOR迭代法与经典AOR迭代法之间的比较定理,最后给出4个例子来说明本文的结论。     

基于自然边界归化的半无界区域上非重叠型区域分解算法

基于半平面上的自然边界归化理论,给出一类带凹槽的半无界区域上椭圆型方程边值问题的非重叠型区域分解算法．证明算法具有与有限元剖分网格参数无关的收敛性,适当选取松弛因子,算法是几何收敛的,同时给出松弛因子的一般取值．     

四阶椭圆变分不等式的微分形式及有限元法的收敛阶

本文通过引入L~2(Ω)→H~1。(Ω)∩ΩH~2(Ω)的连续可逆线性算子A,讨论了固支和简支障碍曲率约问题和平均束问题的变分形式和微分形式,证明了其等价性。然后利用等价的微分形式,讨论了固支障碍问题非协调Adini元逼近及固支和简支带平均曲率约束问题的混合有限元逼近的收敛阶,在只需解u∈H~3(Ω)的正则性条件下,得到其收敛阶为:     

H-矩阵的一个新的预条件Gauss-Seidel迭代方法

给出了解线性方程组Ax=b的一个新的预条件因子P．应用Gauss—Seidel迭代格式于预条件线性方程组PAx=Pb,并证明了当矩阵A为H-矩阵时,此预条件Gauss—Seidel方法是收敛的．最后,数值算例说明文中所给预条件Gauss—Seidel方法是有效的．     

Decomposition method for solving parabolic equations in finite domains

INTRODUCTION The decomposition method was introduced by Adomian(1989;1994)in the1980’s for solving linear and nonlinear functional equations(algebraic,dif-ferential,partial differential equations(PDEs)and systems,integral,differential-delay,integro-differen-tial equations,etc.)(Adomian,1989;1994;Guellal and Cherruault,1995;Adomian et al.,1996;Laffez and Abbaoui,1996;Ndour et al.,1996;Guellal et al.,1997;Abbaoui and Cherruault,1999;Adjedj,1999).This method leads to computable,accurat…