二维分数阶变系数对流-扩散方程的数值解

1 引 言 在古典的微分方程中,利用阶数为实数的分数阶导数代替整数阶导数,能更好地模拟许多物理现象.特别是具有复杂结构的多孔介质中的反常扩散问题.     

三维Laplace方程Cauchy问题的小波解(英文)

本文研究了三维Laplace方程的柯西问题.该问题是不适定的,即其解(若存在)不连续依赖原始数据.利用Meyer小波和小波Galerkin方法,获得了在L2范数意义下的稳定小波逼近解,并且给出分辨率水平的选取方法.     

关于一类非常系数线性递推式的解的显式表示

本文给出了两个指标的非常系数的线性递推式的显式解。有关方法,避免了由于解高阶线性代数方程所带来的困难。其结果,为求解组合计数中相应定解问题,提供了一个明确的计算公式。     

CAUCHY PROBLEM FOR A DEGENERATE PARABOLIC EQUATION WITH NON-DIVERGENCE FORM

In this article, it is shown that there exists a unique viscosity solution of the Cauchy problem for a degenerate parabolic equation with non-divergence form.     

THE CAUCHY PROBLEM FOR A NONLINEAR FAST DIFFUSION EQUATION

In this paper, the existence, uniqueness and continuous dependence on initial data for the Cauchy problem of fast diffusion equation is discussed.     

THE CAUCHY PROBLEM OF THE HARTREE EQUATION

In this paper, we systematically study the wellposedness, illposedness of the Hartree equation, and obtain the sharp local wellposedness, the global existence in Hs, s≥1 and the small scattering result in Hs for 2 〈γ〈 n and s ≥ 2/γ - 1. In addition, we study the nonexistence of nontrivial asymptotically free solutions of the Hartree equation.     

ON THE CAUCHY PROBLEM FOR A SINGULAR INTEGRODIFFERENTIAL EQUATION

The authors establish the existence and uniqueness of global solutions to the Cauchy problem for the third-order Benjamin-Ono equation by the so-called continuation method.     

变系数二元线性差分方程解的显式表示

文章讨论了变系数二元线差分方程求解公式,并给出两个应用实例。     

Helmholtz方程Cauchy问题的间接积分方程方法

 本文处理二维和三维Helmholtz方程的边界数据复原问题.通过利用位势理论近似问题的解,导出了解决Cauchy问题的一种非迭代积分方程方法.为了处理形成问题的不适定性,采用了Tikhonov正则化结合Morozov偏差原理的方法,并且给出了算法的收敛性和误差估计,最后给出了二维和三维的数值算例.通过数值算例我们检验了源点和边界之间距离的关系,算法关于噪声、源点数目的数值收敛性,稳定性.     

变系数波方程振动传递的边界镇定

本文讨论了变系数波方程振动传递的边界镇定,应用黎曼几何方法和迹的正则性得到了所讨论问题的能量一致衰减率.     

变系数波方程振动传递的边界镇定

本文讨论了变系数波方程振动传递的边界镇定,应用黎曼几何方法和迹的正则性得到了所讨论问题的能量一致衰减率.     

A MODIFIED TIKHONOV REGULARIZATION METHOD FOR THE CAUCHY PROBLEM OF LAPLACE EQUATION

In this paper,we consider the Cauchy problem for the Laplace equation,which is severely ill-posed in the sense that the solution does not depend continuously on the data.A modified Tikhonov regularization method is proposed to solve this problem.An error estimate for the a priori parameter choice between the exact solution and its regularized approximation is obtained.Moreover,an a posteriori parameter choice rule is proposed and a stable error estimate is also obtained.Numerical examples illustrate the validity and effectiveness of this method.     

THE CAUCHY PROBLEM FOR A CLASS OF DOUBLY DEGENERATE NONLINEAR PARABOLIC EQUATION

This article studies the Cauchy problem for a class of doubly nonlinear degenerate parabolic equations . Under certain conditions, the author considers its regularized problem and establishes some estimates. On the basis of the estimates, the existence and uniqueness of the generalized solutions in BV space are proved.     

TRICOMI PROBLEM FOR A MIXED EQUATION OF SECOND ORDER WITH DISCONTINUOUS COEFFICIENTS

This paper is devoted to the Tricomi problem for a mixed type equation of second order. The coeffcients are assumed to be discontinuous on the line where the type is changed. The unique existence of the solution to the problem is proved if the domain is small enough. Correspondingly, some estimates on the solution is also established.     

CAUCHY PROBLEM FOR ONE-DIMENSIONAL P-LAPLACIAN EQUATION WITH POINT SOURCE

We prove the existence, uniqueness and finite propagation of disturbance of continuous solutions to the Cauchy problem for one-dimensional p-Laplacian equation with point source.     

UNIQUENESS OF GENERALIZED SOLUTION FOR THE CAUCHY PROBLEM OF TRANSPORTATTION EQUATIONS

1IntroductionInthepresentpaper,weconsidertheuniquenessofsolutionforthetransportationsystemwithinitialdatawherepanduaredensityandvelocityrespectively.Thesystemofcollservationlaws(1.l)describesthefluidmechanicswithconstantpressure,whichisusedinplasmaphysicswhosepressureisassumedtobeconstant.TheCauchyproblemforthissystemisnotwell-posedintheclassofboundedmeasurablefunctions(see[31).In[8],Z.Wang,F.HuangandX.DinghaveprovedtheealstenceofsolutionsdefinedbyLebesgue--Stieltjesintegral.Beforedetaildi…     

GUARANTEED BOUNDS FOR THE SOLUTION OF THE WAVE EQUATION

Abstract

Numerical solution of the wave equation in the form of close lower and upper bounds provides a secure a posteriori error estimate that can be used for efficient accuracy control. The method considered in this paper uses some monotone properties of the differential operator in the wave equation to construct bounds for the solution in the form of trigonometric polynomials of x. Aspects of the numerical implementation, the accuracy of the computed bounds and some numerical examples are discussed.     

THE CAUCHY PROBLEM FOR SOME DISPERSIVE WAVE EQUATIONS

In this paper, we consider the Cauchy problem for some dispersive equations. By means of nonlinear estimate in Besov spaces and fixed point theory, we prove the global well-posedness of the above problem. What‘s more, we improve the scattering result obtained in [1].