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On improving a solution to the ATSP with fixed origin and precedence relationships.

Laureano F. Escudero (1988)

Trabajos de Investigación Operativa

Given the directed graph G1 = (N, A1) with a node origin and a penalty matrix C, the ATSP with fixed origin and precedence relationships (hereafter, ASTP-PR) consists of finding the permutation of the nodes from the set N, such that it minimizes a matrix C based function and does not violate the precedence relationships given by the set A1. In this work we present an algorithm for improving a given feasible solution to the problem, by performing a local search that uses 3- and 4-change based procedures....

On localizing global Pareto solutions in a given convex set

Agnieszka Drwalewska, Lesław Gajek (1999)

Applicationes Mathematicae

Sufficient conditions are given for the global Pareto solution of the multicriterial optimization problem to be in a given convex subset of the domain. In the case of maximizing real valued-functions, the conditions are sufficient and necessary without any convexity type assumptions imposed on the function. In the case of linearly scalarized vector-valued functions the conditions are sufficient and necessary provided that both the function is concave and the scalarization is increasing with respect...

On lower Lipschitz continuity of minimal points

Ewa M. Bednarczuk (2000)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

In this paper we investigate the lower Lipschitz continuity of minimal points of an arbitrary set A depending upon a parameter u . Our results are formulated with the help of the modulus of minimality. The crucial requirement which allows us to derive sufficient conditions for lower Lipschitz continuity of minimal points is that the modulus of minimality is at least linear. The obtained results can be directly applied to stability analysis of vector optimization problems.

On M -stationary points for a stochastic equilibrium problem under equilibrium constraints in electricity spot market modeling

René Henrion, Werner Römisch (2007)

Applications of Mathematics

Modeling several competitive leaders and followers acting in an electricity market leads to coupled systems of mathematical programs with equilibrium constraints, called equilibrium problems with equilibrium constraints (EPECs). We consider a simplified model for competition in electricity markets under uncertainty of demand in an electricity network as a (stochastic) multi-leader-follower game. First order necessary conditions are developed for the corresponding stochastic EPEC based on a result...

On main characteristics of the M / M / 1 / N queue with single and batch arrivals and the queue size controlled by AQM algorithms

Wojciech M. Kempa (2011)

Kybernetika

In the article finite-buffer queueing systems of the M / M / 1 / N type with queue size controlled by AQM algorithms are considered, separately for single and batch arrivals. In the latter case two different acceptance strategies: WBAS (Whole Batch Acceptance Strategy) and PBAS (Partial Batch Acceptance Strategy) are distinguished. Three essential characteristics of the system are investigated: the stationary queue-size distribution, the number of consecutively dropped packets (batches of packets) and the time...

On minimizing total tardiness in a serial batching problem

Philippe Baptiste, Antoine Jouglet (2001)

RAIRO - Operations Research - Recherche Opérationnelle

We study the problem of scheduling jobs on a serial batching machine to minimize total tardiness. Jobs of the same batch start and are completed simultaneously and the length of a batch equals the sum of the processing times of its jobs. When a new batch starts, a constant setup time s occurs. This problem 1 | s-batch | T i is known to be NP-Hard in the ordinary sense. In this paper we show that it is solvable in pseudopolynomial time by dynamic programming.

On Minimizing Total Tardiness in a Serial Batching Problem

Philippe Baptiste, Antoine Jouglet (2010)

RAIRO - Operations Research

We study the problem of scheduling jobs on a serial batching machine to minimize total tardiness. Jobs of the same batch start and are completed simultaneously and the length of a batch equals the sum of the processing times of its jobs. When a new batch starts, a constant setup time s occurs. This problem 1|s-batch | ∑Ti is known to be NP-Hard in the ordinary sense. In this paper we show that it is solvable in pseudopolynomial time by dynamic programming.

On modelling planning under uncertainty in manufacturing.

A. Alonso-Ayuso, L. F. Escudero, M.T. Ortuño (2007)

SORT

We present a modelling framework for two-stage and multi-stage mixed 0-1 problems under uncertainty for strategic Supply Chain Management, tactical production planning and operations assignment and scheduling. A scenario tree based scheme is used to represent the uncertainty. We present the Deterministic Equivalent Model of the stochastic mixed 0-1 programs with complete recourse that we study. The constraints are modelled by compact and splitting variable representations via scenarios.

On necessary optimality conditions in a class of optimization problems

Jiří V. Outrata (1989)

Aplikace matematiky

In the paper necessary optimality conditions are derived for the minimization of a locally Lipschitz objective with respect to the consttraints x S , 0 F ( x ) , where S is a closed set and F is a set-valued map. No convexity requirements are imposed on F . The conditions are applied to a generalized mathematical programming problem and to an abstract finite-dimensional optimal control problem.

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