| 4/1998 |
Reconstruction Of A Compactly Supported Function From The Discrete Sampling Of Its Fourier Transform Jiahong Yin, Alvaro R. De Pierro, Musheng Wei We derive a new relation between the Discrete Fourier Transform of a discrete sampling set of a compactly supported function and its Fourier transform. From this relation we obtain a new window function. We then propose a new efficient algorithm to reconstruct the original function from the discrete sampling of its Fourier transform, which can adopt the fast Fourier transform and has much better accuracy than those in the literature. Several numerical experiments are also provided to demonstrate the results.  rp-1998-4.pdf |
| 3/1998 |
On the number of control sets on flag manifolds of the real simple Lie groups Carlos J. Braga Barros rp-1998-3.pdf |
| 2/1998 |
Dynamic choice of the leaving-face criterion in bound-constrained quadratic minimization Maria A. Diniz-Ehrhardt, Márcia A. Gomes-Ruggiero, Sandra A. Santos In this work we focus our attention on the quadratic subproblem of trust–region algorithms for bound–constrained minimization, proposing and testing dynamic choices for the parameter in charge of the decision of leaving or not the current face of the feasible set. The practical consequences of an appropriate decision of such parameter have shown to be crucial, particularly when dual degenerate and ill-conditioned problems are solved. rp-1998-2.pdf |
| 1/1998 |
Generic one parameter families of reversible vector fields Cláudio A. Buzzi, Marco A. Teixeira In the present paper we study the dynamics of a class of reversible vector fields having eigenvalues (0 ; \alpha i; \alphai ) around their symmetric equilibria. We give a complete list of all normal forms for such vector fields, their versal unfoldings, and the corresponding bifurcation diagrams of codimensional one case. We also obtain some important conclusions on the existence of homoclinic and heteroclinic orbits, invariant tori and symmetric periodic orbits. rp-1998-1.pdf |
| 95/1997 |
The beginning of the Fucik spectrum for the p-Laplacian M. Cuesta, Djairo G. Figueiredo, J. P. Gossez  rp-1997-95.gif, rp-1997-95.pdf |
| 94/1997 |
Análise de Estabilidade para Métodos de Diferenças Finitas: Equações Parabólicas Lineares Saulo Pomponet Oliveira, Petrônio Pulino rp-1997-94.gif, rp-1997-94.pdf |
| 93/1997 |
Equivalence Classes of Quasi-Projective Transformations Marcelo Firer rp-1997-93.gif, rp-1997-93.pdf |
| 92/1997 |
Nonmonotone Spectral Projected Gradient Methods on Convex Sets Ernesto G. Birgin, José Mario Martínez, Marcos Raydan rp-1997-92.gif, rp-1997-92.pdf |
| 91/1997 |
Implementando Critérios Dinâmicos de Decisão Para Controlar a Estratégia de Globalização de ROUXINOL Patrícia Nunes da Silva, Márcia A. Gomes-Ruggiero rp-1997-91.gif, rp-1997-91.pdf |
| 90/1997 |
Resolução de Problemas de Controle Ótimo Utilizando o Algoritmo BOX Alberto Adami, Márcia A. Gomes-Ruggiero rp-1997-90.gif |
