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作者：Rubinov, A. M.; Wu, Z. Y.
作者单位：Federation University Australia
摘要：In this paper we derive necessary and sufficient conditions for some problems of global minimization. Our approach is based on methods of abstract convexity: we use a representation of an upper semicontinuous function as the lower envelope of a family of convex functions. We discuss applications of conditions obtained to the examination of some tractable sufficient conditions for the global minimum and to the theory of inequalities.
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作者：Pap, Gyula
作者单位：Eotvos Lorand University
摘要：A perfect 2-matching of a graph is a vector assigning values 0,1, or 2 to the edges such that the sum of values of edges incident with any node is equal to 2. For restricted perfect 2-matchings, we are also given a collection of allowed odd cycles, and restrict ourselves to those perfect 2-matchings the support of which contains no odd cycle not in this collection. Given a graph and a collection of allowed odd cycles, we provide a TDI description of the convex hull of restricted perfect 2-matc...
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作者：Sager, Sebastian; Bock, Hans Georg; Reinelt, Gerhard
作者单位：Ruprecht Karls University Heidelberg
摘要：Many practical optimal control problems include discrete decisions. These may be either time-independent parameters or time-dependent control functions as gears or valves that can only take discrete values at any given time. While great progress has been achieved in the solution of optimization problems involving integer variables, in particular mixed-integer linear programs, as well as in continuous optimal control problems, the combination of the two is yet an open field of research. We cons...
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作者：Jofre, Alejandro; Wets, Roger J. -B.
作者单位：University of California System; University of California Davis; Universidad de Chile
摘要：We explore convergence notions for bivariate functions that yield convergence and stability results for their maxinf (or minsup) points. This lays the foundations for the study of the stability of solutions to variational inequalities, the solutions of inclusions, of Nash equilibrium points of non-cooperative games and Walras economic equilibrium points, of fixed points, of solutions to inclusions, the primal and dual solutions of convex optimization problems and of zero-sum games. These appli...
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作者：Ioslovich, Ilya; Borshchevsky, Michael; Gutman, Per-Olof
作者单位：Technion Israel Institute of Technology
摘要：The problem of fuel-optimal attitude maneuvering of a space vehicle (SV) with non-fixed time is considered. The state constraint related to the maintenance of artificial gravitation is imposed. This problem is especially important for long-time space missions. The attitude of the space vehicle is controlled by means of a pair of reactive engines which produce a single control torque with fixed direction in the body-fixed frame. An optimal solution is obtained in the class of trajectories belon...
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作者：Louveaux, Francois; Salazar-Gonzalez, Juan-Jose
作者单位：Universidad de la Laguna; University of Namur; Universite Catholique Louvain
摘要：This paper studies how to set the vehicle capacity for traveling Salesman Problems where some of the customer demands are stochastic. The analyses are done for the one-commodity pickup-and-delivery TSP, as this problem also includes the setting of the initial load. The paper first considers feasibility issues. This includes finding the smallest vehicle capacity and some initial load such that a given tour is feasible for all scenarios. Different variants are considered as a function of the tim...
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作者：Pang, Jong-Shi; Stewart, David E.
作者单位：Rensselaer Polytechnic Institute; Rensselaer Polytechnic Institute; University of Iowa
摘要：In the first part of this paper, we establish several sensitivity results of the solution x(t, xi) to the ordinary differential equation (ODE) initial-value problem (IVP) dx/dt = f (x), x(0) = xi as a function of the initial value xi for a non differentiable f (x). Specifically, we show that for Xi(T) = {x(t, xi(0)) : 0 <= t <= T}, (a) if f is B-differentiable on Xi(T), then so is the solution operator x (t; .) at xi(0); (b) if f is semismooth on Xi(T), then so is x(t; .) at xi(0); (c) if f ha...
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作者：Baldacci, Roberto; Mingozzi, Aristide
作者单位：University of Bologna; University of Bologna
摘要：This paper presents a unified exact method for solving an extended model of the well-known Capacitated Vehicle Routing Problem (CVRP), called the Heterogenous Vehicle Routing Problem (HVRP), where a mixed fleet of vehicles having different capacities, routing and fixed costs is used to supply a set of customers. The HVRP model considered in this paper contains as special cases: the Single Depot CVRP, all variants of the HVRP presented in the literature, the Site-Dependent Vehicle Routing Probl...
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作者：Antipin, Anatoly
作者单位：Russian Academy of Sciences
摘要：We consider two-person nonzero-sum game, both in the classical form and in the form of a game with coupled variables. An extra-proximal approach for finding the game's solutions is suggested and justified. We provide our algorithm with an analysis of its convergence.
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作者：Deng, Geng; Ferris, Michael C.
作者单位：University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison
摘要：The sample-path method is one of the most important tools in simulation-based optimization. The basic idea of the method is to approximate the expected simulation output by the average of sample observations with a common random number sequence. In this paper, we describe a new variant of Powell's unconstrained optimization by quadratic approximation (UOBYQA) method, which integrates a Bayesian variable-number sample-path (VNSP) scheme to choose appropriate number of samples at each iteration....
