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111.
112.
113.
Viscosity solutions to a parabolic inhomogeneous equation associated with infinity Laplacian 下载免费PDF全文
We obtain the existence and uniqueness results of viscosity solutions to the initial and boundary value problem for a nonlinear degenerate and singular parabolic inhomogeneous equation of the form ut- ΔN∞u = f,where ΔN∞denotes the so-called normalized infinity Laplacian given by ΔN∞u =1|Du|2 D2 uD u, Du. 相似文献
114.
In nature, plants or animals change their geometric shapes and hence realize different functions or movements. Inspired by the shape changes of plants and animals, several hydrogels that can change their geometric shapes upon external stimuli have been developed. This article provides a brief overview of shape changing hydrogels. First, two strategies to realize the shape changes of hydrogels, that is, preparing hydrogels with inhomogeneous structures and applying inhomogeneous stimuli onto homogeneous hydrogels, are discussed. Then, external stimuli that can actuate the shape changes of the stimuli-responsive hydrogels are presented. The applications of shape changing hydrogels such as soft machines, soft robotics, drug carriers, microfluidic valves, and sensors have been provided in third part. Finally, we offer our perspective on open challenges and future areas of interest for the shape changing hydrogel actuators. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1314–1324 相似文献
115.
A. Yu. Kolesov 《Mathematical Notes》1998,63(5):614-623
We consider the boundary value problem
. Hereu ∈ ℝ2,D = diag{d
1,d
2},d
1,d
2 > 0, and the functionF is jointly smooth in (u, μ) and satisfies the following condition: for 0 <μ ≪ 1 the boundary value problem has a homogeneous (independent ofx) cycle bifurcating from a loop of the separatrix of a saddle. We establish conditions for stability and instability of this
cycle and give a geometric interpretation of these conditions.
Translated fromMatematicheskie Zametki, Vol. 63, No. 5, pp. 697–708, May, 1998.
This research was supported by the Russian Foundation for Basic Research under grant No. 96-01-00207. 相似文献
116.
I. Pultarová 《Numerical Linear Algebra with Applications》2016,23(2):373-390
An asymptotic convergence analysis of a new multilevel method for numerical solution of eigenvalues and eigenvectors of symmetric and positive definite matrices is performed. The analyzed method is a generalization of the original method that has recently been proposed by R. Ku?el and P. Vaněk (DOI: 10.1002/nla.1975) and uses a standard multigrid prolongator matrix enriched by one full column vector, which approximates the first eigenvector. The new generalized eigensolver is designed to compute eigenvectors. Their asymptotic convergence in terms of the generalized residuals is proved, and its convergence factor is estimated. The theoretical analysis is illustrated by numerical examples. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
117.
Ernst Eberlein M’hamed Eddahbi S. M. Lalaoui Ben Cherif 《Applied Mathematical Finance》2016,23(3):236-260
The aim of this article is to compute Greeks, i.e. price sensitivities in the framework of the Lévy LIBOR model. Two approaches are discussed. The first approach is based on the integration-by-parts formula, which lies at the core of the application of the Malliavin calculus to finance. The second approach consists of using Fourier-based methods for pricing derivatives. We illustrate the result by applying the formula to a caplet price where the jump part of the driving process of the underlying model is given by a time–inhomogeneous Gamma process and alternatively by a Variance Gamma process. 相似文献
118.
Tian‐jun Wang 《Mathematical Methods in the Applied Sciences》2016,39(13):3824-3835
In this paper, we develop a spectral method for mixed inhomogeneous Dirichlet/Neumann/Robin boundary value problems defined on rectangle. Some results on two‐dimensional Legendre approximation in Jacobi‐weighted Sobolev space are established. As examples of applications, spectral schemes are provided for two model problems with mixed inhomogeneous boundary conditions. The spectral accuracy in space of proposed algorithms are proved. Efficient implementations are presented. Numerical results demonstrate their high accuracy and confirm the theoretical analysis well. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
119.
A. V. Martynenko A. F. Tedeev 《Computational Mathematics and Mathematical Physics》2007,47(2):238-248
The following quasilinear parabolic equation with a source term and an inhomogeneous density is considered: . The conditions on the parameters of the problem are found under which the solution to the Cauchy problem blows up in a finite time. A sharp universal (i.e., independent of the initial function) estimate of the solution near the blowup time is obtained.
相似文献
$\rho (x)\frac{{\partial u}}{{\partial t}} = div(u^{m - 1} \left| {Du} \right|^{\lambda - 1} Du) + u^p $
120.
本文对两个非均匀半平面粘结的非均匀平面的裂纹问题作了分析,文中假定两种材料的泊松比v相同,但杨氏模量随坐标x按不同形式的指数函数变化.本文使用非均匀平面问题的单裂纹解及富氏变换方法, 使问题归为一个柯西型奇异积分方程,最后对应力强度因子的计算给出了若干数值例子. 相似文献