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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 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 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.

A method of multiobjective decision making using a vector value function.

Sixto Ríos-Insua, Jacinto González Pachón, Alfonso Mateos (1994)

Qüestiió

A decision situation with partial information on preferences by means of a vector value function is assumed. The concept of minimum value dispersion solution as a reference point joined with a pseudodistance function from such a point and a dispersion level ε, lead to the notion of ε-dispersion set. The dispersion level represents the amount of value that the decision maker can be indifferent to, therefore he should choose his most preferred solution in this set. Convergence properties, as well...

A Mixed Integer Quadratic Programming Model for the Low Autocorrelation Binary Sequence Problem

Kratica, Jozef (2012)

Serdica Journal of Computing

In this paper the low autocorrelation binary sequence problem (LABSP) is modeled as a mixed integer quadratic programming (MIQP) problem and proof of the model’s validity is given. Since the MIQP model is semidefinite, general optimization solvers can be used, and converge in a finite number of iterations. The experimental results show that IQP solvers, based on this MIQP formulation, are capable of optimally solving general/skew-symmetric LABSP instances of up to 30/51 elements in a moderate time....

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