Cauchy Problem of Some Doubly Degenerate Parabolic Equations with Initial Datum a Measure

This paper discusses the Cauchy problem of the equationu_t=▽·(▽_u~m|~(p-2)▽_u~m)-u~qwith initial datum a measure.Under the assumption of the parameters,one proves the existence andnou-existence of the non-negative generalized solution.     

非自治退化抛物-双曲方程的柯西问题

非自治退化抛物-双曲型方程可以描述许多自然现象.主要研究这类方程的柯西问题,建立了动力学公式,在对流函数、扩散函数适当光滑性的基础上,证明了该问题动力学解的存在唯一性.     

拟线性退化抛物方程Cauchy问题的解

对来自金融数学领域的方程_xxu+u_yu-_tu=c（x,y,t,u）,（x,y,t）∈Q_T=R²×[0,T)的Cauchy问题,给出了一种新的熵解的定义,得到了其适定性结果.可以证明所得到的解还是强解,即方程中所出现的各阶偏导数几乎处处连续.最后讨论了解的爆破性质以及与解的间断点相关的几何性质.     

带吸收项的非线性双重退缩抛物方程的Cauchy问题

讨论带吸收项的非线性双重退缩抛物方程ut=div(│↓△u^m│^p-2↓△u^m)-u^q u(x,0)=u0(x)的Cauchy问题。     

关于一类拟线性退化抛物方程

对拟线性退化抛物方程θ_(xx)u uθ_yu-θ_tu=f(·,u)进行了研究,得到了在[O,T]×Ω上的初边值问题解的存在唯—性,这里要求T充分小．     

The Asymptotic Behavior of Solutions of Some Doubly Degenerate Nonlinear Parabolic Equations

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The Cauchy Problem for Shilov Parabolic Equations

We establish well-posed solvability of the Cauchy problem for the Shilov parabolic equations with time-dependent coefficients whose initial data are tempered distributions. For a certain class of equations we state necessary and sufficient conditions for unique solvability of the Cauchy problem whose properties with respect to the spatial variable are typical for a fundamental solution. The results are characterized only by the order and the parabolicity exponent.     

On the Solvability of Degenerate Quasilinear Parabolic Equations of Second Order

In this paper, we consider nonlinear degenerate quasilinear parabolic initial boundary value problems of second order. Using results from the theory of pseudomonotone operators, we show that there exists at least one weak solution in a suitable weighted Sobolev space. Received February 4, 1997, Revised October 20, 1997, Accepted March 17, 1998     

二阶退化拟线性抛物型方程解的存在性

本文研究二阶退化拟线性抛物型方程的初－边值问题．在适当带权的Ｓｏｂｏｌｅｖ空间,我们利用伪单调算子理论证明了解的存在性．     

一类重特征方程柯西问题的唯一性

本文利用Carleman估计和算子链方法,研究了一类初始曲线含重特征点的二阶退缩双曲型方程的柯西问题在分布类中的唯一性.     

An Inverse Problem of Identifying the Radiative Coefficient in a Degenerate Parabolic Equation

The authors investigate an inverse problem of determining the radiative coefficient in a degenerate parabolic equation from the final overspecified data. Being different from other inverse coefficient problems in which the principle coefficients are assumed to be strictly positive definite, the mathematical model discussed in this paper belongs to the second order parabolic equations with non-negative characteristic form, namely, there exists a degeneracy on the lateral boundaries of the domain. Based on the optimal control framework, the problem is transformed into an optimization problem and the existence of the minimizer is established. After the necessary conditions which must be satisfied by the minimizer are deduced, the uniqueness and stability of the minimizer are proved. By minor modification of the cost functional and some a priori regularity conditions imposed on the forward operator, the convergence of the minimizer for the noisy input data is obtained in this paper. The results can be extended to more general degenerate parabolic equations.     

The Cauchy Problem for Certain Inhomogeneous Difference-Differential Parabolic Equations

We prove an existence and uniqueness theorem for classical solutions of the Cauchy problem for an inhomogeneous equation of parabolic type with shifted space variables.     

Cauchy Problem for Semilinear Wave Equations in Four Space Dimensions with Small Initial Data

In this paper, we consider the Cauchy problem ◻u(t,x) = |u(t,x)|^p, (t,x) ∈ R^+ × R^4 t = 0 : u = φ(x), u_t = ψ(x), x ∈ R^4 where ◻ = ∂²_t - Σ^4_{i=1}∂²_x_i, is the wave operator, φ, ψ ∈ C^∞_0 (R^4). We prove that for p > 2 the problem has a global solution provided tile initial data is sufficiently small.     

源于DNA的非线性波动方程组的Cauchy问题(英文)

本文首先证明源于DNA的非线性波动方程组的周期边值问题局部古典解的存在性和唯一性.其次通过周期边值问题序列证明这个方程组的Cauchy问题存在唯一的局部古典解.     

两个空间变量的拟线性抛物方程初值问题解的正则性

本文研究了两个空间变量的拟线性退缩抛物方程Ｃａｕｃｈｙ问题广义解的正则性问题。推广了文献［１］的结果。     

The Cauchy Problem of the Porous Medium Equation with Absorption

In this paper we study the existence of solution for the following Cauchy problem {u_t = Δu^m - u^p u(x,0) = u_0(x) We show how the growth condition of initial trace is determined by the absorption.     

一类拟线性退化抛物方程的Cauchy问题

对方程α（xx）u＋uαyu-αtu=f（·,u）,（x,y,t）∈R^2×（0,T）的Cauchy问题,给出了一个整体BV-弱解的定义,证明了该弱解的连续性.     

非齐次线性退化富有组的柯西问题

对非齐次线性退化富有组的柯西问题,证明了在奇性的发生处解的Ｃ０模必趋于无穷。     

退缩抛物方程组解的全局存在性

利用上下解方法讨论一类退缩抛物方程组存在全局解的条件,并证明了在一定条件下全局解的收敛性.