Relatórios de Pesquisa

25/2004 Prova Alternativa para a Identidade 12 de Slater
I. M. Craveiro, José Plínio O. Santos
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24/2004 A Sequential Quadratic Programming Algorithm with a Piecewise Linear Merit Function
Francisco A. M. Gomes Neto

A sequential quadratic programming algorithm for solving nonlinear programming problems is presented. The new feature of the algorithm is related to the definition of the merit function. Instead of using one penalty parameter per iteration and increasing it as the algorithm progresses, we suggest that a new point is to be accepted if it stays sufficiently below the piecewise linear function defined by some previous iterates on the $(f; ||C||^2_2)$ space. Therefore, the penalty parameter is allowed to decrease between successive iterations. Besides, one need not to decide how to update the penalty parameter. This approach resembles the filter method introduced by Fletcher and Leyffer [7], but it is less tolerant since a merit function is still used.


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23/2004 Multiple Solutions for an Elliptic Equation with Critical Hardy-Sobolev Exponents Via the Domain Topology
Marcelo F. Furtado

Let $\Omega \subset \real^N$ be a smooth bounded domain such that $0 \in \Omega$, $N \geq 3$, $0 \leq s


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22/2004 Reproductivity for a Nematic Liquid Crystal Model
Blanca Climent-Ezquerra, Francisco Guillén-Gonzáles, Marko A. Rojas-Medar

In this paper we prove existence of weak solution with the reproductivity in time property, for a penalized PDE's system related to a nematic liquid crystal model. This problem is relatively explicit when time­independent Dirichlet boundary conditions are imposed for the orientation of crystal molecules. For the time­dependent case, the verification of a maximum principle for weak reproductive solutions is fundamental in the argument. Finally, the relation between reproductive and periodic in time solutions and their dependence respect to the regularity will be pointed out, being completely different the 2D and 3D cases.


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21/2004 Continuity for S-Convex Fuzzy Processes
Juliana Cervelati, María Dolores Jiménez-Gamero, Filidor E. Vilca-Labra, Marko A. Rojas-Medar

In a previous paper we introduced the concept of s-convex fuzzy mapping and established some properties. In this work we study the continuity for s-convex fuzzy processes.


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20/2004 Analysis of Variance for Genomic Sequences in Unbalanced Designs
Roberta de Souza, Hildete P. Pinheiro, Cibele Q. da Silva, Sérgio F. dos Reis

In the study of genetic divergence among organisms, generally the analysis is done directly from the DNA molecule. Therefore, a possible outcome is categorical being one out of four categories (looking at the nucleotide level). Light \& Margolin (1971) developed an analysis of variance for categorical data (CATANOVA) and Pinheiro et al. (2000) employed a similar measure of variation and extended the CATANOVA procedure taking into account several positions in the sequence for balanced designs. Here we consider variable number of sequences in each group, that is, the samples are unbalanced. In order to test the null hypothesis of homogeneity among groups, the asymptotic distribution of the test statistic was found and its power is evaluated. An application of the test to real data is illustrated using resampling methods such as the bootstrap to generate the empirical distribution of the test statistics.


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19/2004 Homotopies for the Generalized Bar Complex Associated to Certain 3-Rowed Weyl Modules
Mari Sano

In \cite{BR2}, Buchsbaum and Rota presented a generalized bar complex associated to certain 3-rowed Weyl modules and proved that this complex is in fact a resolution via an induction on the number of overlaps between the second and third rows and a fundamental exact sequence (\cite{AB}). In this paper we study the structure of this resolution by constructing a splitting contracting homotopy for the complexes corresponding to certain shapes. We also use the method of proof to give a basis for the syzygies that is more structured than the basis given in \cite{sano}.


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18/2004 Estudo do Desempenho de Métodos para Minimização Irrestrita com Controle de Passo
Sandra A. Santos, Larissa Oliveira Xavier
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17/2004 Curvature on reductive homogeneous spaces
Marlio Paredes, Sofía Pinzón

In this work, we consider the general flag manifold $\vb_\Theta$ as a naturally reductive homogeneous space endows with an$U$--invariant metric $\Lambda^{\Theta}$ and an invariant almost-complex structure $J^\Theta$. Our central reference is the section 2 in chapter X of \cite{kn}. The main objective of this work is to explore the form for the {\em Riemannian connection} associated with the metric $\Lambda^{\Theta}$ in order to calculate some classes of curvatures which allow to compare the results that appear in the geometric flag manifolds with characterizations already existing (see, for example, \cite{siu}, \cite{eell2}).


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16/2004 Entropy of Multiplier Operators on Compact Globally Symmetric Spaces of Rank 1
Alexander Kushpel, Sérgio A. Tozoni

Estimates of entropy of multiplier operators $\Lambda = \{\lambda_{k}\}_{k=1}^{\infty}$ on compact globally symmetric spaces of rank 1 (i.e. on $S^{d}$, $P^{d}(\RR)$, $P^{d}(\CC)$, $P^{d}(\HH)$, $P^{16}({\rm Cay})$ ) are established. It is shown that these estimates have sharp orders in different important cases. In particular, we give sharp orders of entropy of standard Sobolev's classes $W^{\gamma}_{p}(M^{d})$ in $L_{q}(M^{d})$ for all $1 < p, q < \infty$.


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