非光滑非凸向量极值问题的真有效解

本文考虑非光滑非凸向量极值问题的真有效解,其主要结果如下:(1)Borwein真有效解与Benson真有效解的等价性;(2)向量极值问题的真有效解与标量极值问题的最优解的等价性;(3)广义鞍点定理;(4)真有效解的必要和充分条件。     

向量优化问题有效解的稳定性

运用标量化的方法,通过锥正定真有效解的上半连续性讨论了无限维赋范空间中锥有效解的部分上半连续性,证明了锥有效解的通有稳定性.在此基础上,进一步证明,在Baire纲的意义下,绝大多数的向量优化问题至少存在一个锥正定真有效解是本质的有效解,换句话说,绝大多数的向量优化问题锥有效解是几乎下半连续的.     

Viscosity solutions with shocks

A solution of single nonlinear first order equations may develop jump discontinuities even if initial data is smooth. Typical examples include a crude model equation describing some bunching phenomena observed in epitaxial growth of crystals as well as conservation laws where jump discontinuities are called shocks. Conventional theory of viscosity solutions does not apply. We introduce a notion of proper (viscosity) solutions to track whole evolutions for such equations in multi‐dimensional spaces. We establish several versions of comparison principles. We also study the vanishing viscosity method to construct a unique global proper solution at least when the evolution is monotone in time or the initial data is monotone in some sense under additional technical assumptions. In fact, we prove that the graph of approximate solutions converges to that of a proper solution in the Hausdorff distance topology. Such a convergence is also established for conservation laws with monotone data. In particular, local uniform convergence outside shocks is proved. © 2001 John Wiley & Sons, Inc.     

多目标规划有效解的Kuhn—Tucker必要条件

本文提出一个新的约束规格,导出可微多目标规划的有效解的Kuhn-Tucker必要条件,并证明在此条件下,有效解是Kuhn-Tucker真有效解。     

On Unique Solutions of Multiple-State Optimal Design Problems on an Annulus

We study the uniqueness and explicit derivation of the relaxed optimal solutions, corresponding to the minimization of weighted sum of potential energies for a mixture of two isotropic conductive materials on an annulus. Recently, it has been shown by Burazin and Vrdoljak that even for multiple-state problems, if the domain is spherically symmetric, then the proper relaxation of the problem by the homogenization method is equivalent to a simpler relaxed problem, stated only in terms of local proportions of given materials. This enabled explicit calculation of a solution on a ball, while problems on an annulus appeared to be more tedious. In this paper, we discuss the uniqueness of a solution of this simpler relaxed problem, when the domain is an annulus and we use the necessary and sufficient conditions of optimality to present a method for explicit calculation of the unique solution of this simpler proper relaxation, which is demonstrated on an example.     

二阶非线性微分方程组的正规解及极限边值问题

本文对微分方程组其中a(t)>0,r(t)>0,t≥t₀;f(x)对x>0正值递减;g(y)>0,给出存在正规解,有界正规解或两类无穷区间[c,∞)(c≥t₀)上边值问题解的充要条件.同时给出若干例子说明结果的条件.     

序线性空间中广义半似凸集值映射向量优化的Benson真有效性

在序线性空间中建立了广义半似凸集值映射的择一定理.利用向量闭包,引进了集值优化的Benson真有效解.在广义半似凸的假设下,获得了Benson真有效性意义下的标量化定理,Lagrangian乘子定理和鞍点定理.     

集值优化问题在Henig真有效解意义下的导数型最优性条件

给出实的赋范空间中集值映射的Henig真有效解集的一些性质,并利用集值映射的相依上图导数和集值映射的次微分给出了集值优化问题Henig真有效解的最优性条件的充要条件.     

A singular-degenerate free boundary problem arising from the moisture evaporation in a partially saturated porous medium

Summary We consider a moisture evaporation process in a porous medium which is partially saturated by a fluid. The mathematical model is a singular-degenerate nonlinear parabolic free boundary problem. We first transform the problem into a weak form in a fixed domain and then derive some uniform estimates for the proper approximate solution. The existence of a weak solution is established by a compactness argument. Finally, the regularity of the solution and interfaces are investigated.     

Singularly perturbed evolution equations in Banach spaces

The singular perturbation method is applied to systems of linear evolution equations in Banach spaces with one of the time derivatives multiplied by a small parameter. An asymptotic solution of any given order is shown to consist of inner and outer terms obtained by a proper choice of initial conditions, and to converge uniformly to the exact solution.     

Painlevé-Kuratowski Convergences of the solution sets to perturbed generalized systems

In this paper,we obtain the Painlev’e-Kuratowski Convergence of the efficient solution sets,the weak efficient solution sets and various proper efficient solution sets for the perturbed generalized system with a sequence of mappings converging in a real locally convex Hausdorff topological vector spaces.     

A-调和方程很弱解的正则性

本文证明了二阶拟线性偏微分方程很弱解的正则性．若ｕ是（１）的一个很弱解并属于一个合适的包含Ｗ１,ｐ　ｌｏｃ（ ）的空间,则ｕ属于 （ ）,即ｕ是（１）通常意义下的弱解．变分积分弱极值的同样结果被得到．     

Convergence Results for Henig Proper Efficient Solution Sets of Vector Optimization Problems

In this article, we discuss the convergence of Henig proper minimal point sets and Henig proper efficient solution sets for (strict) proper quasi-convex vector optimization problems when the data of the perturbed problems converges to the data of the original problem in the sense of Painlevé-Kuratowski. Our main results are new and different from those in the literature.     

Proper deflating subspaces: properties,algorithms and applications

An algorithm for computing proper deflating subspaces with specified spectrum for an arbitrary matrix pencil is presented. The method uses refined algorithms for computing the generalized Schur form of a matrix pencil and enlightens the connection that exists between reducing and proper deflating subspaces. The proposed algorithm can be applied for computing the stabilizing solution of the generalized algebraic Riccati equation, a recently introduced concept which extends the usual algebraic Riccati equation.     

Partial regularity for the Navier-Stokes-Fourier system

This paper addresses a nonstationary flow of heat-conductive incompressible Newtonian fluid with temperature-dependent viscosity coupled with linear heat transfer with advection and a viscous heat source term, under Navier/Dirichlet boundary conditions. The partial regularity for the velocity of the fluid is proved for each proper weak solution, that is, for such weak solutions which satisfy some local energy estimates in a similar way to the suitable weak solutions of the Navier-Stokes system. Finally, we study the nature of the set of points in space and time upon which proper weak solutions could be singular.     

Optimality conditions for proper efficient solutions of vector set-valued optimization

Based on the concept of an epiderivative for a set-valued map introduced in J. Nanchang Univ. 25 (2001) 122-130, in this paper, we present a few necessary and sufficient conditions for a Henig efficient solution, a globally proper efficient solution, a positive properly efficient solution, an f-efficient solution and a strongly efficient solution, respectively, to a vector set-valued optimization problem with constraints.     

Partially overdetermined elliptic boundary value problems

We consider semilinear elliptic Dirichlet problems in bounded domains, overdetermined with a Neumann condition on a proper part of the boundary. Under different kinds of assumptions, we show that these problems admit a solution only if the domain is a ball. When these assumptions are not fulfilled, we discuss possible counterexamples to symmetry. We also consider Neumann problems overdetermined with a Dirichlet condition on a proper part of the boundary, and the case of partially overdetermined problems on exterior domains.     

Error estimates of proper orthogonal decomposition eigenvectors and Galerkin projection for a general dynamical system arising in fluid models

We study estimates for proper orthogonal decomposition eigenvectors and eigenvalues as well as error estimates between the exact solution of a 2D Navier–Stokes model and the numerical approach when the proper orthogonal decomposition method is considered. These estimates are also extended when bifurcation diagram are calculated using the so called p-POD or SPOD methods with a new cut-off criterion to minimize noisy modes produced by the p-POD method.     

二维Helmholtz方程不适定问题的一种算子软化正则法

本文研究带有混合边界的二维Helmholtz方程不适定问题.为了获得稳定的数值解，利用基于de la ValléePoussin算子的软化正则方法，得到了正则近似解，给出正则近似解与精确解之间在先验参数选取规则之下的误差估计，并通过数值实验检验了数据有噪声扰动时方法的有效性和稳定性.     

Optimal control of backward stochastic heat equation with Neumann boundary control and noise

This paper considers a stochastic control problem in which the dynamic system is a controlled backward stochastic heat equation with Neumann boundary control and boundary noise and the state must coincide with a given random vector at terminal time. Through defining a proper form of the mild solution for the state equation, the existence and uniqueness of the mild solution is given. As a main result, a global maximum principle for our control problem is presented. The main result is also applied to a backward linear-quadratic control problem in which an optimal control is obtained explicitly as a feedback of the solution to a forward–backward stochastic partial differential equation.