Resistant estimates for high dimensional and functional data based on random projections

We herein propose a new robust estimation method based on random projections that is adaptive and automatically produces a robust estimate, while enabling easy computations for high or infinite dimensional data. Under some restricted contamination models, the procedure is robust and attains full efficiency. We tested the method using both simulated and real data.Fil: Fraiman, Jacob Ricardo. Universidad de San Andrés; Argentina. Universidad de la República; Uruguay. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Svarc, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de San Andrés; Argentin

Redescripción de la pupa de Mallochohelea termophila (Diptera: Ceratopogonidae)

Se describe, fotografía e ilustra la exuvia pupal de Mallochohelea termophila (Spinelli), en especial sobre la base de la serie-tipo. Las pupas de la serie-tipo fueron recolectadas mediante pinzas en un arroyo termal, adheridas a rocas, aproximadamente a 200 m del manatial y las pupas de Uruguay mediante el uso de un cucharón tanto en ambientes lóticos como lénticos. Ellas fueron criadas hasta adultos en el laboratorio. Ésta es la primera descripción detallada de una pupa de una especie de Mallochohelea y el primer registro de la especie para Uruguay. Se destacan semejanzas y diferencias con las pupas de Neobezzia.The pupal exuvia of Mallochohelea termophila (Spinelli) is redescribed, photographed and illustrated mainly based on the type-series. Pupae of the type-series were collected with forceps from a thermal stream and were attached to rocks about 200 m from the spring head. Pupae from Uruguay were collected with a dipper in lotic and lentic environments. They were reared to adults in the laboratory. This is the first detailed pupal description of a species of Mallochohelea, and the first record of this species from Uruguay. Similarities and differences with the pupae of Neobezzia are provided.Fil: Ronderos, Maria Marcela. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Spinelli, Gustavo Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

On the existence of bounded solutions for a nonlinear elliptic system

This work deals with the system $(-\Delta)^m u= a(x) v^p$, $(-\Delta)^m v=b(x) u^q$ with Dirichlet boundary condition in a domain \Omega\subset\RR^n, where $\Omega$ is a ball if $n\ge 3$ or a smooth perturbation of a ball when $n=2$. We prove that, under appropriate conditions on the parameters ($a,b,p,q,m,n$), any non-negative solution $(u,v)$ of the system is bounded by a constant independent of $(u,v)$. Moreover, we prove that the conditions are sharp in the sense that, up to some border case, the relation on the parameters are also necessary. The case $m=1$ was considered by Souplet in \cite{PS}. Our paper generalize to $m\ge 1$ the results of that paper

On well-posedness of the Cauchy problem for the wave equation in static spherically symmetric spacetimes

We give simple conditions implying the well-posedness of the Cauchy problem for the propagation of classical scalar fields in general (n+2)-dimensional static and spherically symmetric spacetimes. They are related to properties of the underlying spatial part of the wave operator, one of which being the standard essentially self-adjointness. However, in many examples the spatial part of the wave operator turns out to be not essentially selfadjoint, but it does satisfy a weaker property that we call here quasi essentially self-adjointness, which is enough to ensure the desired well-posedness. This is why we also characterize this second property. We state abstract results, then general results for a class of operators encompassing many examples in the literature, and we finish with the explicit analysis of some of them.Comment: 36 pages. Final version to appear in Classical and Quantum Gravit

Defeasible reasoning in dynamic domains

The design of intelligent agents is a key issue for many applications. Since there is no universally accepted definition of intelligence, the notion of rational agency was proposed by Russell as an alternative for the characterization of intelligent agency. A rational agent must have models of itself and its surroundings to use them in its reasoning. To this end, this paper develops a formalism appropriate to represent the knowledge of an agent. Moreover, if dynamic environments are considered, the agent should be able to observe the changes in the world, and integrate them into its existing beliefs. This motivates the incorporation of perception capabilities into our framework. The abilities to perceive and act, essential activities in a practica! agent, demand a timely interaction with the environment. Given that the cognitive process of a rational agent is complex and computationally expensive, this interaction may not be easy to achieve. To solve this problem, we propase inference mechanisms that rely on the use precompiled knowledge to optimize the reasoning process.I Workshop de Agentes y Sistemas Inteligentes (WASI)Red de Universidades con Carreras en Informática (RedUNCI

Palpomyia ryszardi sp. n. from Peru (Diptera: Ceratopogonidae)

A new species of the Palpomyia tibialis group, Palpomyia ryszardi, is described from male and female specimens and from their pupal exuviae from material collected in the vicinities of Iquitos in Peruvian Amazonia. The adult is compared with the most similar Neotropical congener, Palpomyia pseudolacustris SPINELLI & DIPPOLITO, and the pupa with the American species Palpomyia subaspera (COQUILLETT). Descriptions are accompanied by photographs and ink illustrations.Fil: Spinelli, Gustavo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Ronderos, Maria Marcela. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Estudios Parasitologicos y de Vectores. Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Centro de Estudios Parasitologicos y de Vectores; Argentin