Steepest Descent Method
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. A SURVEY ON MULTIOBJECTIVE DESCENT METHODS
We present a rigorous and comprehensive survey on extensions to the multicriteria setting of three well-known scalar optimization algorithms. Multiobjective versions of the steepest descent, the projected gradient and the Newton methods are analyzed in detail. At each iteration, the search directions of these methods are computed by solving real-valued optim
Pesqui. Oper.. Publicado em: 2014-12
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2. Far-field dynamic behavior of a half-space under an inertial strip foundation subjected to a time-harmonic force
Recent research works demonstrated that the interaction between the loads and the carrying structure's boundary which is related to the inertia of the load is an influential factor on the dynamic response of the structure. Although effects of the inertia in moving loads were considered in many works, very few papers can be found on the inertial effects of th
Lat. Am. j. solids struct.. Publicado em: 2013-05
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3. A Review of Gradient Algorithms for Numerical Computation of Optimal Trajectories
Abstract: In this paper, two classic direct methods for numerical computation of optimal trajectories were revisited: the steepest descent method and the direct one based upon the second variation theory. The steepest descent method was developed for a Mayer problem of optimal control, with free final state and fixed terminal times. Terminal constraints on t
J. Aerosp. Technol. Manag.. Publicado em: 2012-06
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4. On analytic singularities of a class of vector fields on the torus / Sobre singularidades analíticas de soluções de uma classe de campos vetoriais no Toro
O objetivo principal deste trabalho é o estudo da regularidade anallítica global de certos operadores diferenciais definidos no toro. Uma ferramenta fundamental utilizada neste estudo são as séries parciais de Fourier, que nos permitem caracterizar tanto as distribuições periódicas quanto as funções anallíticas reais periódicas através do comport
Publicado em: 2009
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5. Comparação de métodos de otimização para o problema de ajuste de histórico em ambientes paralelos
The process of history matching aims on the determination of the models parameters from a petroleum reservoir. Once adjusted, the models can be used for the prediction of the reservoir behavior. This work presents a comparsion of dierent optimization methods for this problem s solution. Derivative based methods are compared to a genetic algorithm. In particu
Publicado em: 2009
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6. Inverse aerodynamic design using the adjoint method applied to the Euler equations. / Projeto inverso aerodinâmico utilizando o método adjunto aplicado às equações de Euler.
Um desafio constante no projeto aerodinâmico de uma superfície é obter a forma geométrica que permite, baseado em uma determinada medida de mérito, o melhor desempenho possível. No contexto de projeto de aeronaves de transporte, o desempenho ótimo em cruzeiro é a principal meta do projetista. Nesse cenário, o uso da Dinâmica do Fluidos Computaciona
Publicado em: 2008
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7. Numerical computation of optimal low-thrust limited-power trajectories - Transfers between coplanar circular orbits
An algorithm based on gradient techniques, proposed in a companion paper, is applied to numerical analysis of optimal low-thrust limited-power trajectories for simple transfer (no rendezvous) between coplanar circular orbits in a central Newtonian gravity field. The proposed algorithm combines the main positive characteristics of two well-known methods in op
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2005-06
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8. On the convergence properties of the projected gradient method for convex optimization
When applied to an unconstrained minimization problem with a convex objective, the steepest descent method has stronger convergence properties than in the noncovex case: the whole sequence converges to an optimal solution under the only hypothesis of existence of minimizers (i.e. without assuming e.g. boundedness of the level sets). In this paper we look at
Computational & Applied Mathematics. Publicado em: 2003
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9. Desenvolvimento e analise de novos algoritmos preditivos para equalização cega
In this work, the blind equalization of a communication channel will be considered. The work will focus on the discussion of blind equalization techniques that are based on linear prediction theory. These are called predictive techniques for blind equalization. Firstly, the need for an equalizer in a communication system will be discussed, as well as the adv
Publicado em: 1997
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10. Calculation of the Reaction Cross Section from a Rate Constant by the Method of Steepest-Descent
The reaction cross section of a bimolecular reaction has been calculated from the corresponding rate constant by the inverse Laplace transform. In carrying out the inverse Laplace transform, the method of steepest-descent has been used. As applications, the reaction cross sections for the rate constant of k(T) = k′ Tne-E0/kT and for the rate constant of th
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11. An extension of the steepest descent method for Riemann-Hilbert problems: The small dispersion limit of the Korteweg-de Vries (KdV) equation
This paper extends the steepest descent method for Riemann-Hilbert problems introduced by Deift and Zhou in a critical new way. We present, in particular, an algorithm, to obtain the support of the Riemann-Hilbert problem for leading asymptotics. Applying this extended method to small dispersion KdV (Korteweg-de Vries) equation, we (i) recover the varia
The National Academy of Sciences.
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12. Equilibrium and stability code for a diffuse plasma
A computer code to investigate the equilibrium and stability of a diffuse plasma in three dimensions is described that generalizes earlier work on a sharp free boundary model. Toroidal equilibria of a plasma are determined by considering paths of steepest descent associated with a new version of the variational principle of magnetohydrodynamics that involves