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111.
A numerical method based on finite difference method with variable mesh is given for self-adjoint singularly perturbed two-point boundary value problems. To obtain parameter- uniform convergence, a variable mesh is constructed, which is dense in the boundary layer region and coarse in the outer region. The uniform convergence analysis of the method is discussed. The original problem is reduced to its normal form and the reduced problem is solved by finite difference method taking variable mesh. To support the efficiency of the method, several numerical examples have been considered.  相似文献   
112.
The advection‐diffusion equation has a long history as a benchmark for numerical methods. Taylor‐Galerkin methods are used together with the type of splines known as B‐splines to construct the approximation functions over the finite elements for the solution of time‐dependent advection‐diffusion problems. If advection dominates over diffusion, the numerical solution is difficult especially if boundary layers are to be resolved. Known test problems have been studied to demonstrate the accuracy of the method. Numerical results show the behavior of the method with emphasis on treatment of boundary conditions. Taylor‐Galerkin methods have been constructed by using both linear and quadratic B‐spline shape functions. Results shown by the method are found to be in good agreement with the exact solution. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010  相似文献   
113.
The effect of liquid on the propagation of waves in a micropolar elastic layer with stretch has been investigated. The frequency and wave velocity equations for symmetric and antisymmetric vibrations are derived. Propagation of monochromatic waves in a micropolar elastic layer with stretch is discussed. Results of this analysis reduce to those without stretch.  相似文献   
114.
研究了具有立方对称性及两个弛豫时间的微极热弹性介质在调和时间源中的响应.采用了Fourier变换以及数值逆变换技术.在物理域中,得到了位移、应力、微转动和温度分布的数值结果.将微极立方晶体法向位移、法向力应力、切向耦合应力和温度分布的计算结果,与微极各向同性固体的结果进行比较.绘制了指定材料的数值结果图形.还推断了某些特殊情况的结果.  相似文献   
115.
研究了无应力作用条件下,均匀、各向同性、圆柱形微极结构弹性板中波的传播.导出了对称和斜对称模式下波传播的特征方程.对短波这一极端情况,无应力圆板中对称和斜对称模态波的特征方程退化为Pmyle曲表面波频率方程.并得到薄板的计算结果.给出了位移和微转动分量,并绘制了相应图形.给出了若干特殊情况的研究结果及对称和斜对称模态特征方程的图示.  相似文献   
116.
We introduce the notion of a complementary cone and a nondegenerate linear transformation and characterize the finiteness of the solution set of a linear complementarity problem over a closed convex cone in a finite dimensional real inner product space. In addition to the above, other geometrical properties of complementary cones have been explored.  相似文献   
117.
The purpose of this paper is to present a brief survey of fast direct methods for solving elliptic boundary-value problems. The methods reviewed are based on Fourier analysis, block reduction techniques, and marching algorithms. First, the Poisson equation with Dirichlet and mixed boundary conditions are considered. Then we go to more general elliptic problems and irregular regions.  相似文献   
118.
The symmetric marching technique has been developed to solve the Poisson equation with Dirichlet boundary conditions. The method has been combined with a mesh refinement technique, which is used as an appropriate interpolation scheme to obtain a solution of the problem on finer grids. The effectiveness of the method has been demonstrated by solving some test examples.  相似文献   
119.
Journal of Theoretical Probability - In this work, we consider the stochastic generalized Burgers–Huxley equation perturbed by space–time white noise and discuss the global solvability...  相似文献   
120.
A new approach to Nori's weak Lefschetz theorem is described. The new approach, which involves the -method, avoids moving arguments and gives much stronger results. In particular, it is proved that if and are connected smooth projective varieties of positive dimension and is a holomorphic immersion with ample normal bundle, then the image of in is of finite index. This result is obtained as a consequence of a direct generalization of Nori's theorem. The second part concerns a new approach to the theorem of Burns which states that a quotient of the unit ball in () by a discrete group of automorphisms which has a strongly pseudoconvex boundary component has only finitely many ends. The following generalization is obtained. If a complete Hermitian manifold of dimension has a strongly pseudoconvex end and for some positive constant , then, away from , has finite volume.

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