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141.
《Optimization》2012,61(1-2):35-110
We endeavour to answer the question of the title, or rather the question of how much one can extend convex analysis to a wider framework in which some convexity features remain. Subdifferential calculus and duality are the main directions we consider 相似文献
142.
《Optimization》2012,61(3-4):249-266
The paper offers an abstract structure called environment (of mathematical programming) in which a pair of dual programs is settled symmetrically. Given an environment, the concepts of an optimization program, its dual and the associated Lagrangean are formalized and studied. The usual asymmetries in certain types of mathematical programming are due to selection of asymmetric environments. Common types of programming like: linear, nonlinear, convex, integer etc. are reviewed in the proposed framework. 相似文献
143.
《Optimization》2012,61(4):317-321
The purpose of this paper is to discuss some generalizations of convex functionals and obtain some applications to optimality and duality 相似文献
144.
《Optimization》2012,61(1):25-45
The paper (Part I) describes an approach to duality in fractional programming on the basis of another kind of conjugate functions. The connections to some duality concepts (the Lagrange-duality and duality concepts of Craven and Schaible) are investigated and some new proofs of strong duality theorems are given. 相似文献
145.
《Applied Mathematical Modelling》2014,38(5-6):1607-1611
In this paper, He’s homotopy perturbation method (HPM) is applied for solving linear programming (LP) problems. This paper shows that some recent findings about this topic cannot be applied for all cases. Furthermore, we provide the correct application of HPM for LP problems. The proposed method has a simple and graceful structure. Finally, a numerical example is displayed to illustrate the proposed method. 相似文献
146.
Affine semigroups are convex sets on which there exists an associative binary operation which is affine separately in either variable. They were introduced by Cohen and Collins in 1959. We look at examples of affine semigroups which are of interest to matrix and operator theory and we prove some new results on the extreme points and the absorbing elements of certain types of affine semigroups. Most notably we improve a result of Wendel that every invertible element in a compact affine semigroup is extreme by extending this result to linearly bounded affine semigroups. 相似文献
147.
Jitender Kumar 《代数通讯》2013,41(12):5152-5169
In order to study the structure of A +(B n )—the affine near-semiring over a Brandt semigroup—this work completely characterizes the Green's classes of its semigroup reducts. In this connection, this work classifies the elements of A +(B n ) and reports the size of A +(B n ). Further, idempotents and regular elements of the semigroup reducts of A +(B n ) have also been characterized and studied some relevant semigroups in A +(B n ). 相似文献
148.
149.
Yunshyong Chow 《Journal of Difference Equations and Applications》2013,19(2):169-187
We investigate asymptotic dynamics of the classical Leslie–Gower competition model when both competing populations are subject to Allee effects. The system may possess four interior steady states. It is proved that for certain parameter regimes both competing populations may either go extinct, coexist or one population drives the other population to extinction depending on initial conditions. 相似文献
150.
Anna Cima 《Journal of Difference Equations and Applications》2013,19(8):1107-1133
AbstractIn this article, we extract and study the zero entropy subfamilies of a certain family of birational maps of the plane. We find these zero entropy mappings and give the invariant fibrations associated to them. 相似文献