摘要:

The convergence of barrier-projection methods of optimization is investigated on the basis of vector Lyapunov functions. Continuous and discrete variants of barrier-projection methods are considered.

ISSN:1055-6788    

DOI:10.1080/10556789408805562

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor

摘要:

We address the problem of scheduling a fleet of vehicles, stationed in different depots, in such a way to perform a set of time-tabled trips and to minimize a given objective function. We consider the consti that requires each vehicle to return to the starting depot. This problem, known asMultiple Depot V& Scheduling(MD-VSP), isNP-hard. In this paper we formulate the MD-VSP as a Set Partitioning Prot with side constraints (SP). We describe a procedure that, without using the SP matrix, computes a lower bound to the MD-VSP by finding a heuristic solution to the dual of the continuous relaxation of SP. dual solution obtained is used to reduce the number of variables in the SP in such a way that the resu SP problem can be solved by usual branch and bound techniques. The computational results show effectiveness of the proposed method.

ISSN:1055-6788    

DOI:10.1080/10556789408805563

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor

摘要:

In this paper we describe a cutting plane algorithm to solve max-cut problems on complete graphs. We show that the separation problem over the cut polytope can be reduced to the separation problem over the cut cone and we give a separation algorithm for a class of inequalities valid over the cut cone:the hypermetric inequalities.Computational results are given.

ISSN:1055-6788    

DOI:10.1080/10556789408805564

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor

摘要:

Strong duality has been proven for the integer linear programming problem, where a super-additive function prices out the activities and closes the duality gap. In this paper an alternative, equivalent formulation of the dual problem there exist dual prices, which activities and close the duality gap, and where the dual objective function is an affine variables.

ISSN:1055-6788    

DOI:10.1080/10556789408805565

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor

摘要:

In this paper we enlighten the structure of dipaths of prescribed parity in planar digraphs and we present a polynomial time algorithm for solving the following problem

ISSN:1055-6788    

DOI:10.1080/10556789408805566

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor

摘要:

The present paper is devoted to the application of the space transformation techniques for solving nonlinear programming problems. By using surjective mapping the original constrained optimization problem is transformed to a problem in a new space with only equality constraints For the numerical solution of the latter problem the stable version of the gradient-projection and Newton's methods are used. After inverse transformation to the original space a family of numerical methods for solving optimization problems with equality and inequality constraints is obtained. The proposed algorithms are based on the numerical integration of the systems of ordinary differential equations. These algorithms do not require feasibility of starting and current points, but they preserve feasibility. As a result of space transformation the vector fields of differential equations are changed and additional terms are introduced which serve as a Barrier preventing the trajectories from leaving the feasible set. A proof of convergence is given.

ISSN:1055-6788    

DOI:10.1080/10556789408805567

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor

ISSN:1055-6788    

DOI:10.1080/10556789408805551

出版商:Gordon and Breach Science Publishers    

年代:1994

数据来源: Taylor