All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 10 Next

Displaying 181 – 200 of 884

Showing per page

A linear programming approach to error bounds for random walks in the quarter-plane

Jasper Goseling, Richard J. Boucherie, Jan-Kees van Ommeren (2016)

Kybernetika

We consider the steady-state behavior of random walks in the quarter-plane, in particular, the expected value of performance measures that are component-wise linear over the state space. Since the stationary distribution of a random walk is in general not readily available we establish upper and lower bounds on performance in terms of another random walk with perturbed transition probabilities, for which the stationary distribution is a geometric product-form. The Markov reward approach as developed...

A linear programming based analysis of the CP-rank of completely positive matrices

Yingbo Li, Anton Kummert, Andreas Frommer (2004)

International Journal of Applied Mathematics and Computer Science

A real matrix A is said to be completely positive (CP) if it can be decomposed as A = BB^T, where the real matrix B has exclusively non-negative entries. Let k be the rank of A and Φ_k the least possible number of columns of the matrix B, the so-called completely positive rank (cp-rank) of A. The present work is devoted to a study of a general upper bound for the cp-rank of an arbitrary completely positive matrix A and its dependence on the ordinary rank k. This general upper bound of the cp-rank...

A Linguistic Fuzzy Approach to the Consensus Reaching in Multiple Criteria Group Decision-making Problems

Vojtěch Sukač, Jana Talašová, Jan Stoklasa (2016)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

The paper introduces a new method of reaching a consensus in multiple criteria group decision-making under fuzziness. This model is based on the general definition of the ‘soft’ consensus introduced by Kacprzyk and Fedrizzi in 1986. The fuzzy evaluations of alternatives express degrees of fulfillment of the given goals by the respective alternatives for each expert. The selection of the best alternative is based on the fuzzy consensus by experts. For this purpose a set of alternatives which are...

A logarithm barrier method for semi-definite programming

Jean-Pierre Crouzeix, Bachir Merikhi (2008)

RAIRO - Operations Research

This paper presents a logarithmic barrier method for solving a semi-definite linear program. The descent direction is the classical Newton direction. We propose alternative ways to determine the step-size along the direction which are more efficient than classical line-searches.

A Markov chain model for traffic equilibrium problems

Giandomenico Mastroeni (2002)

RAIRO - Operations Research - Recherche Opérationnelle

We consider a stochastic approach in order to define an equilibrium model for a traffic-network problem. In particular, we assume a markovian behaviour of the users in their movements throughout the zones of the traffic area. This assumption turns out to be effective at least in the context of urban traffic, where, in general, the users tend to travel by choosing the path they find more convenient and not necessarily depending on the already travelled part. The developed model is a homogeneous Markov...

A Markov chain model for traffic equilibrium problems

Giandomenico Mastroeni (2010)

RAIRO - Operations Research

We consider a stochastic approach in order to define an equilibrium model for a traffic-network problem. In particular, we assume a Markovian behaviour of the users in their movements throughout the zones of the traffic area. This assumption turns out to be effective at least in the context of urban traffic, where, in general, the users tend to travel by choosing the path they find more convenient and not necessarily depending on the already travelled part. The developed model is a homogeneous...

A mathematical model for an optimal appointed delivery date on a home delivery market

Hidefumi Kawakatsu, Hiroaki Sandoh (2005)

RAIRO - Operations Research - Recherche Opérationnelle

In recent years, the home delivery market has rapidly been growing since customers can purchase a variety of products very easily via Internet. At the same time, however, customers tend to switch from a supplier to another seeking for better service for them. For this reason, it is necessary for suppliers to enclose their customers by means of various kinds of service and strategy. An appointed delivery date of a product ordered by a customer is one of important factors of supplier’s services. From...

A mathematical model for an optimal appointed delivery date on a home delivery market

Hidefumi Kawakatsu, Hiroaki Sandoh (2010)

RAIRO - Operations Research

In recent years, the home delivery market has rapidly been growing since customers can purchase a variety of products very easily via Internet. At the same time, however, customers tend to switch from a supplier to another seeking for better service for them. For this reason, it is necessary for suppliers to enclose their customers by means of various kinds of service and strategy. An appointed delivery date of a product ordered by a customer is one of important factors of supplier's services....

A memetic algorithm for the vehicle routing problem with time windows

Nacima Labadi, Christian Prins, Mohamed Reghioui (2008)

RAIRO - Operations Research

This article deals with the vehicle routing problem with time windows (VRPTW). This problem consists in determining a least-cost set of trips to serve customers during specific time windows. The proposed solution method is a memetic algorithm (MA), a genetic algorithm hybridised with a local search. Contrary to most papers on the VRPTW, which minimize first the number of vehicles, our method is also able to minimize the total distance travelled. The results on 56 classical instances are compared...

A Metaheuristic Approach to Solving the Generalized Vertex Cover Problem

Milanović, Marija (2010)

Mathematica Balkanica New Series

AMS Subj. Classification: 90C27, 05C85, 90C59The topic is related to solving the generalized vertex cover problem (GVCP) by genetic algorithm. The problem is NP-hard as a generalization of well-known vertex cover problem which was one of the first problems shown to be NP-hard. The definition of the GVCP and basics of genetic algorithms are described. Details of genetic algorithm and numerical results are presented in [8]. Genetic algorithm obtained high quality solutions in a short period of time.

Currently displaying 181 – 200 of 884