Pseudo-monotone complementarity problems in Hilbert space

In this paper, some existence results for a nonlinear complementarity problem involving a pseudo-monotone mapping over an arbitrary closed convex cone in a real Hilbert space are established. In particular, some known existence results for a nonlinear complementarity problem in a finite-dimensional Hilbert space are generalized to an infinite-dimensional real Hilbert space. Applications to a class of nonlinear complementarity problems and the study of the post-critical equilibrium state of a thin elastic plate subjected to unilateral conditions are given.This research was partially supported by the National Science Foundation Grant DMS-89-13089, Department of Energy Grant DE-FG03-87-ER-25028, and Office of Naval Research Grant N00014-89-J-1659. The authors would like to express their sincere thanks to Professor S. Schaible, School of Administration, University of California, Riverside, for his helpful suggestions and comments. They also thank the referees for their comments and suggestions that improved this paper substantially.     

Second-order conditions for extremum problems with nonregular equality constraints

Combining results of Avakov about tangent directions to equality constraints given by smooth operators with results of Ben-Tal and Zowe, we formulate a second-order theory for optimality in the sense of Dubovitskii-Milyutin which gives nontrivial conditions also in the case of equality constraints given by nonregular operators. Secondorder feasible and tangent directions are defined to construct conical approximations to inequality and equality constraints which within a single construction lead to first- and second-order conditions of optimality for the problem also in the nonregular case. The definitions of secondorder feasible and tangent directions given in this paper allow for reparametrizations of the approximating curves and give approximating sets which form cones. The main results of the paper are a theorem which states second-order necessary condition of optimality and several corollaries which treat special cases. In particular, the paper generalizes the Avakov result in the smooth case.This research was supported by NSF Grant DMS-91-009324, NSF Grant DMS-91-00043, SIUE Research Scholar Award and Fourth Quarter Fellowship, Summer 1992.     

B样条在一些渐近组合问题中的应用

本文考察了B样条函数及其导数的渐近性质,并给出了收敛阶;考察了经典Eulerian数和两类广义Eulerian数的渐近性质;给出了以Hermite多项式表示的细化Eulerian数的渐近形式.Carlitz等人利用中心极限定理得到Eulerian数渐近公式的逼近阶为43阶.利用样条方法,我们得到更为精确的逼近阶.将样条方法引入到组合数的渐近分析中,为离散对象的研究提供了一种新的分析方法.     

Tykhonov well-posedness for lexicographic equilibrium problems

In this paper, we consider the vector equilibrium problems involving lexicographic cone in Banach spaces. We introduce the new concepts of the Tykhonov well-posedness for such problems. The corresponding concepts of the Tykhonov well-posedness in the generalized sense are also proposed and studied. Some metric characterizations of well-posedness for such problems are given. As an application of the main results, several results on well-posedness for the class of lexicographic variational inequalities are derived.     

A meshless Galerkin method for Dirichlet problems using radial basis functions

In this paper, a numerical method is given for partial differential equations, which combines the use of Lagrange multipliers with radial basis functions. It is a new method to deal with difficulties that arise in the Galerkin radial basis function approximation applied to Dirichlet (also mixed) boundary value problems. Convergence analysis results are given. Several examples show the efficiency of the method using TPS or Sobolev splines.     

Some mathematical problems in seriation

Some mathematical aspects of seriation are studied in this paper. Certain conditions on an abundance or an incidence matrix have been given in the past which imply that there exists a permutation of its rows so that the resulting matrix is a Q matrix (in which case the original matrix is said to be a pre-Q). These types of results have applications to chronologically ordering archaeological provenances under certain circumstances. Unfortunately these conditions are deficient both theoretically and practically, in that for much archaeological data the conditions are not necessarily true yet the corresponding provenances do have chronological orderings. Here we are able to generalize these results in two ways. First we are able to establish necessary and sufficient conditions on the rows of a matrix for it to be pre-Q. These conditions are local in that they concern only certain triples and quadruples of the rows. Secondly, we are able to interpret seriation in terms of a ternary relation R on a set A and prove the results in this general context. In this form the theorem says that if only certain of the triples and quadruples are R-strings, then the whole set A is an R-string, and so has a linear order consistent with the ternary relation R. This would appear to generalize a theorem of P. C. Fishburn. Both aspects of the generalization mean that the results stated herein have a wider applicability than those given heretofore. Possibly more importantly than this is that they lead to numerical invariants, called the fixing number and the related linear rigidity, of such an R-string on A. The archaeological interpretation of these is given in the paper and data supplied which illustrates this point. Finally various other conditions on products and representations of relations are stated which imply that A is an R-string. One of these generalizes and completes a theorem of D. G. Kendall.     

Finite dimensional approximation of two-parameter nonlinear problems

Summary. In this paper we study a general theory for the numerical approximation of functional nonlinear two-parameter problems in a neighbourhood of an isola center. The results are also valid for a certain class of perturbed bifurcation points. The abstract theory is applied to the Galerkin approximation of nonlinear variational posed problems. In this case, as a consequence of the error being orthogonal to the approximating space, we prove the superconvergence of the perturbation parameter, whereas for the bifurcation parameter and the solution we obtain the same order as in the linear problem. Numerical results are given for the one-dimensional Brussellator model. Received June 10, 1992 / Revised version received May 16, 1994     

Error analysis of approximate solutions to parametric vector quasiequilibrium problems

In this paper, we give some results on error estimates of approximate solutions to parametric vector quasiequilibrium problems in metric linear spaces. Under some special cases, the error estimates are equivalent to H?lder stability or Lipschitz stability of the set-valued solution map at a given point. An application to variational inequalities is also presented.     

On the Kneser property for some parabolic problems

In this paper we consider both a phase-field systems of equations and an abstract differential inclusion for which the uniqueness of the Cauchy problem fails. We prove that the Kneser property holds, that is, that the set of values attained by the solutions at every moment of time is compact and connected. These results are also applied for proving that the global attractors in both cases are connected. An application is given to a reaction–diffusion equation with discontinuous nonlinearity.     

On nonlinear simultaneous Chebyshev approximation problems

This paper is concerned with the problem of nonlinear simultaneous Chebyshev approximation in a real continuous function space. Some results on existence are established, in addition to characterization conditions of Kolmogorov type and also of alternation type. Applications are given to approximation by rational functions, by exponential sums and by Chebyshev splines with free knots.     

Relaxation techniques applied to some loading problems

In this paper a two-stage loading problem, dealing with allocation of jobs to machines, is studied. The outer problem is to choose a subset among a number of available machines such that a feasible assigment exists and the total cost price is minimized. The inner problem, is then to find the optimal allocation, given the subset of machines and some assigment criterion at this lower level. It is shown that the choice of problem formulation can be crucial for the strength of the continuous relaxation. Computational results are also presented     

Quadratic assignment problems

This paper surveys quadratic assignment problems (QAP). At first several applications of this problem class are described and mathematical formulations of QAPs are given. Then some exact solution methods and good heuristics are outlined. Their computational behaviour is illustrated by numerical results. Further recent results on the asymptotic probabilistic behaviour of QAPs are outlined.     

Strong pseudo-convex mappings in dual problems

In this paper some relations between strong pseudo-convexity and other generalized convexity-properties of mappings (convex-likeness, quasi -convexity) into Banach-spaces are described. Furthermore necessary and sufficient conditions for the strong pseudo-convexity of a mapping are presented. Especially, sufficient conditions for the strong pseudo-convexity of composite mappings are proved. Applying these results a correct ion of a direct duality theorem given by Chandra and Lata is formulated.     

On the generalized vector equilibrium problems

In this paper, generalized vector equilibrium problems are studied and some existence theorems of solutions for these problems in the setting of topological vector spaces are proved. Sufficient conditions for the set of solutions to be compact and convex are given. Our results improve some recent results in this field.     

Well-posedness for general parametric quasi-variational inclusion problems

In this paper, we aim to suggest the new concept of well-posedness for the general parametric quasi-variational inclusion problems (QVIP). The corresponding concepts of well-posedness in the generalized sense are also introduced and investigated for QVIP. Some metric characterizations of well-posedness for QVIP are given. We prove that under suitable conditions, the well-posedness is equivalent to the existence of uniqueness of solutions. As applications, we obtain immediately some results of well-posedness for the parametric quasi-variational inclusion problems, parametric vector quasi-equilibrium problems and parametric quasi-equilibrium problems.     

A finite element lumped mass scheme for solving eigenvalue problems of circular arches

Summary In this paper, we present a finite element lumped mass scheme for eigenvalue problems of circular arch structures, and give error estimates for the approximation. They assert that approximate eigenvalues and eigenfuctions converge to the exact ones. Some numerical examples are also given to illustrate our results.     

Large deviations and related problems for absorbing Markov chains

In this paper, large deviations and their connections with several other fundamental topics are investigated for absorbing Markov chains. A variational representation for the Dirichlet principal eigenvalues is given by the large deviation approach. Kingman’s decay parameters and mean ratio quasi-stationary distributions of the chains are also characterized by the large deviation rate function. As an application of these results, we interpret the “stationarity” of mean ratio quasi-stationary distributions via a concrete example. An application to quasi-ergodicity is also discussed.     

A hybrid projective method for solving system of equilibrium problems with demicontractive mappings applicable in image restoration problems

In this paper, we propose a general iterative scheme based on CQ projection method for finding a common solution of system of equilibrium problems and the fixed point set of a finite family of demicontractive mappings. We also prove strong convergence of the scheme to a common element of the two above-described sets. We then give a numerical example to justify our main result. An example is given in an infinite dimensional space for supporting our main result. Moreover, we apply our main result to solve the unconstrained image restoration problems with a finite family of blurring operators. Our results extend and improve some existing results in the literature.     

Generalized asymptotic functions in nonconvex multiobjective optimization problems

In this paper, we use generalized asymptotic functions and second-order asymptotic cones to develop a general existence result for the nonemptiness of the proper efficient solution set and a sufficient condition for the domination property in nonconvex multiobjective optimization problems. A new necessary condition for a point to be efficient or weakly efficient solution is given without any convexity assumption. We also provide a finer outer estimate for the asymptotic cone of the weakly efficient solution set in the quasiconvex case. Finally, we apply our results to the linear fractional multiobjective optimization problem.