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Derivative-free nonlinear optimization filter simplex

Aldina Correia, João Matias, Pedro Mestre, Carlos Serodio (2010)

International Journal of Applied Mathematics and Computer Science

The filter method is a technique for solving nonlinear programming problems. The filter algorithm has two phases in each iteration. The first one reduces a measure of infeasibility, while in the second the objective function value is reduced. In real optimization problems, usually the objective function is not differentiable or its derivatives are unknown. In these cases it becomes essential to use optimization methods where the calculation of the derivatives or the verification of their existence...

Derivatives of orbital function and an extension of Berezin-Gel’fand’s theorem

Tin-Yau Tam, William C. Hill (2016)

Special Matrices

A generalization of a result of Berezin and Gel’fand in the context of Eaton triples is given. The generalization and its proof are Lie-theoretic free and requires some basic knowledge of nonsmooth analysis. The result is then applied to determine the distance between a point and a G-orbit or its convex hull.We also discuss the derivatives of some orbital functions.

Des explications pour reconnaître et exploiter les structures cachées d’un problème combinatoire

Hadrien Cambazard, Narendra Jussien (2006)

RAIRO - Operations Research - Recherche Opérationnelle

L’identification de structures propres à un problème est souvent une étape clef pour la conception d’heuristiques de recherche comme pour la compréhension de la complexité du problème. De nombreuses approches en Recherche Opérationnelle emploient des stratégies de relaxation ou de décomposition dès lors que certaines struc- tures idoines ont été identifiées. L’étape suivante est la conception d’algorithmes de résolution qui puissent intégrer à la volée, pendant la résolution, ce type d’information....

Des explications pour reconnaître et exploiter les structures cachées d'un problème combinatoire

Hadrien Cambazard, Narendra Jussien (2007)

RAIRO - Operations Research

L'identification de structures propres à un problème est souvent une étape clef pour la conception d'heuristiques de recherche comme pour la compréhension de la complexité du problème. De nombreuses approches en Recherche Opérationnelle emploient des stratégies de relaxation ou de décomposition dès lors que certaines struc- tures idoines ont été identifiées. L'étape suivante est la conception d'algorithmes de résolution qui puissent intégrer à la volée, pendant la résolution, ce type d'information....

Designing a ship course controller by applying the adaptive backstepping method

Anna Witkowska, Roman Śmierzchalski (2012)

International Journal of Applied Mathematics and Computer Science

The article discusses the problem of designing a proper and efficient adaptive course-keeping control system for a seagoing ship based on the adaptive backstepping method. The proposed controller in the design stage takes into account the dynamic properties of the steering gear and the full nonlinear static maneuvering characteristic. The adjustable parameters of the achieved nonlinear control structure were tuned up by using the genetic algorithm in order to optimize the system performance. A realistic...

Detection of influential points by convex hull volume minimization

Petr Tichavský, Pavel Boček (1998)

Kybernetika

A method of geometrical characterization of multidimensional data sets, including construction of the convex hull of the data and calculation of the volume of the convex hull, is described. This technique, together with the concept of minimum convex hull volume, can be used for detection of influential points or outliers in multiple linear regression. An approximation to the true concept is achieved by ordering the data into a linear sequence such that the volume of the convex hull of the first...

Détermination d'une période économique robuste dans le cadre du modèle de Wilson

Philippe Vallin (2010)

RAIRO - Operations Research

This paper presents results about the optimal order interval in a context of fuzzy information about inventory management. The classical inventory model is based on well known cost and demand rate. In practice, this accurate estimation is very difficult to obtain, even impossible. Consequently, we propose a solution, not optimal in a classical sense, but allowing to choose an action which is not far from the optimal policy whatever the economic parameters may be. These parameters belong to a...

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