Dynamics and Shape of Brightest Cluster Galaxies

We identified Brightest Cluster Members (BCM) on DSS images of 1083 Abell clusters, derived their individual and host cluster redshifts from literature and determined the BCM ellipticity. Half the BCMs move at a speed higher than 37 % of the cluster velocity dispersion sigma_{cl}, suggesting that most BCMs are part of substructures falling into the main cluster. Both, the BCM's velocity offset in units of sigma_{cl}, and BCM ellipticity, weakly decrease with cluster richness.Comment: 2 pages, 2 figures, Proc. ESO Workshop "Groups of galaxies in the nearby Universe", Santiago, Chile, 5-9 Dec. 2005, ESO Astrophysics Symposia, eds. I. Saviane, V. Ivanov & J. Borissova, Springer-Verla

A method to construct refracting profiles

We propose an original method for determining suitable refracting profiles between two media to solve two related problems: to produce a given wave front from a single point source after refraction at the refracting profile, and to focus a given wave front in a fixed point. These profiles are obtained as envelopes of specific families of Cartesian ovals. We study the singularities of these profiles and give a method to construct them from the data of the associated caustic.Comment: 12 pages, 5 figure

Robust control of the distributed solar collector field ACUREX using MPC for tracking

17th IFAC World Congress 2008. Seoul (Korea). 06/07/2008This paper presents the application of a robust model predictive control for tracking of piece-wise constant references (RMPCT) to a distributed collector field, ACUREX, at the solar power plant of PSA (Solar Plant of Almería). The main characteristic of a solar power plant is that the primary energy source, solar radiation, cannot be manipulated. Solar radiation varies throughout the day, causing changes in plant dynamics and strong disturbances in the process. The real plant is assumed to be modeled as a linear system with additive bounded uncertainties on the states. Under mild assumptions, the proposed RMPCT can steer the uncertain system in an admissible evolution to any admissible steady state, that is, under any change of the set point. This allows us to reject constant disturbances compensating the effect of then changing the setpoint

Introducing Linear Matrix Inequalities in a Control Course

7TH IFAC SYMPOSIUM ON ADVANCES IN CONTROL EDUCATION 21/06/2006 MadridThe important role that linear matrix inequalities have attained in the last years makes it compulsory to include them in the education of a control engineer. As the development of efficient semidefinite programming algorithms date from the early nineties, there is a lack of teaching experience in this field (at least when it is compared with other well established aspects of control theory). This paper proposes a simple way to introduce linear matrix inequalities in a control course. The main objective of the paper is to show that in the formulation of (robust) control problems as linear matrix inequalities a very reduced number of elementary technical results are required. It is illustrated how to introduce, in a progressive way, these technical results along with motivating examples. All of this is done in such a way that it facilitates the assimilation of this important subject. The presented methodology has been successfully applied for more than four years in a doctoral course on control theory

Solving the brachistochrone and other variational problems with soap films

We show a method to solve the problem of the brachistochrone as well as other variational problems with the help of the soap films that are formed between two suitable surfaces. We also show the interesting connection between some variational problems of dynamics, statics, optics, and elasticity.Comment: 16 pages, 11 figures. This article, except for a small correction, has been submitted to the American Journal of Physic

Probabilistic interval predictor based on dissimilarity functions

This work presents a new methodology to obtain probabilistic interval predictions of a dynamical system. The proposed strategy uses stored past system measurements to estimate the future evolution of the system. The method relies on the use of dissimilarity functions to estimate the conditional probability density function of the outputs. A family of empirical probability density functions, parameterized by means of two scalars, is introduced. It is shown that the proposed family encompasses the multivariable normal probability density function as a particular case. We show that the presented approach constitutes a generalization of classical estimation methods. A validation scheme is used to tune the two parameters on which the methodology relies. In order to prove the effectiveness of the presented methodology, some numerical examples and comparisons are provided.Comment: 10 pages, 3 figure

Métodos estatísticos para análise de Y-STRs em genética forense

Tese de mestrado em Bioestatística, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2011A implementação dos marcadores de DNA nas ciências forenses consistiu no maior avanço nesta área nos últimos vinte anos. Os fenómenos de mutação e recombinação genética contribuem para uma grande diversidade genética, o que se traduz no facto de todos os indivíduos, com excepção de gémeos verdadeiros, apresentarem sequências de DNA diferentes entre si, mas invariváveis em todas as suas células. Estas características permitem a sua aplicação na área forense em investigações criminais, relações de parentesco, imigração, pessoas desaparecidas em acidentes de massa e estudos históricos\antropológicos. Nos últimos dez anos os marcadores de DNA específicos dos indivíduos do sexo masculino, Y-STRs, foram estudados e aplicados em diferentes laboratórios na área forense. Estes marcadores permitem a identificação das linhagens paternas do indivíduos e esta informação pode ser de grande importância nos casos de abuso sexual e de investigação de parentesco. No entanto a sua correcta aplicação nos casos do Serviço de Genética e Biologia Forense implica a implementação de um método científico adequado para avaliar a probabilidade de coincidência de dois perfis genéticos. Para este objectivo foi implementado um kit de estudo de Y-STRs, designado por AmpFlSTR® Yfiler™ (Applied Biosystems), previamente desenvolvido e validado para a área forense e aplicado em 197 pares pai\filho, provenientes de uma base de dados da população de referência do Sul de Portugal. Este estudo permitiu realizar inferências populacionais, estimar taxas de mutação da linha germinal paterna e efectuar cálculos de probabilidade de coincidência de perfis genéticos (matching probabilities) em diferentes tipos de casos estudados. As inferências populacionais foram realizadas com diferentes conjuntos deY-STRs, designadas por Haplotipo minimo, Haplotipo Estendido e Haplotipo completo, de forma a verificar qual o conjunto de Y STRs que permite obter a maior diversidade genética A análise com os diferentes conjuntos de haplótipos revelou a presença de 171, 183 e 191 haplotipos diferentes, correspondendo a diversidades genéticas de 0.6411, 0.6403 e 0.6508. No que diz respeito à metodologia aplicada recorrendo à formulação bayesiana, verificou-se que a metodologia recorrendo à distribuição a priori Beta permite estimar valores de taxas de mutação mais próximos dos valores referenciados por outros autores, disponíveis no site www.yhrd.org. O valor mais baixo da taxa de mutação obtido foi de 6.010-4 (5.747-4 – 3.242-4 ) para o marcador DYS438. Estes resultados contribuiram para a estimativa das probabilidades de coincidência de dois perfis genéticos. Estes cálculos foram efetuados recorrendo a diferentes metodologias, nomeadamente, método frequencista, método de “haplotype survyeing” e método de Charles Brenner. Os resultados obtidos com as diferentes metodologias, permitiram concluir que a metodologia “Haplotype Surveying” é presentemente a mais adequada para aplicação na área forense como actualmente está implementada.DNA analysis has been the greatest technological advance in forensic science in the past twenty years. Due to mutation and recombination no two persons, except true twins, have the same DNA sequence, wich enables to determine DNA sequence in every biological sample, and this knowlodge can be used in the investigation of crime, kinship relationships, immigration, missing persons, mass disasters and historical cases. In the last ten years, among DNA markers with forensic interest, a few with potencial to identify male –specific DNA, Y-STRs, were described and implemented in most forensic genetic laboratorys. These markers are very important since they contribute to identify male lineages and this information can be invaluable in cases of sexual assault and in kinship testing, as well as in anthropological and population genetics studies. However to apply Y-STRs in Forensic Genetics Service from National Institute of Legal Medicine, it is convenient to have a scientific method to analyse and evaluate the evidential strength of a Y-haplotype match. For this purpose, a 17 locus microsatellite kit, AmpFlSTR® Yfiler™ (Applied Biosystems), previously developed and validated for forensic cases, was adopted in a 197 father son\pairs south Portugal reference database, in order to make population inferences, Y-STR germline mutation rates estimation, and matching probabilities evaluations. Population inferences were done with different sets of Y STRs markers, classified as Complete Haplotype, Extended Haplotype and Minimal Haplotype, in order to study which set can give the strongest genetic diversity. A total of 171,183, 191 haplotypes were observed when analysed the Minimal Haplotype, Extended Haplotype and Complete Haplotype, respectively, corresponding to genetic diversity 0.6411, 0.6403 and 0.6508. The locus specific mutation rates were estimated with Bayesian formulation, and the best approximation was obtained with a priori Beta distribution. These results contributed to estimate matching probabilities in different kind of cases, kinship and criminal ones, with three distinct methodologies, frequencist, haplotype surveying and Brenner’s, in order to distinguish the best one to apply in the laboratory

The Rich Globular Cluster System of Abell 1689 and the Radial Dependence of the Globular Cluster Formation Efficiency

We study the rich globular cluster (GC) system in the center of the massive cluster of galaxies Abell 1689 (z=0.18), one of the most powerful gravitational lenses known. With 28 HST/ACS orbits in the F814W bandpass, we reach magnitude I_814=29 with >90% completeness and sample the brightest ~5% of the GC system. Assuming the well-known Gaussian form of the GC luminosity function (GCLF), we estimate a total population of N(GC_total) = 162,850 GCs within a projected radius of 400kpc. As many as half may comprise an intracluster component. Even with the sizable uncertainties, which mainly result from the uncertain GCLF parameters, this is by far the largest GC system studied to date. The specific frequency S_N is high, but not uncommon for central galaxies in massive clusters, rising from S_N~5 near the center to ~12 at large radii. Passive galaxy fading would increase S_N by ~20% at z=0. We construct the radial mass profiles of the GCs, stars, intracluster gas, and lensing-derived total mass, and we compare the mass fractions as a function of radius. The estimated mass in GCs, M(GC_total)=3.9x10^10 Msun, is comparable to ~80% of the total stellar mass of the Milky Way. The shape of the GC mass profile appears intermediate between those of the stellar light and total cluster mass. Despite the extreme nature of this system, the ratios of the GC mass to the baryonic and total masses, and thus the GC formation efficiency, are typical of those in other rich clusters when comparing at the same physical radii. The GC formation efficiency is not constant, but varies with radius, in a manner that appears similar for different clusters; we speculate on the reasons for this similarity in profile.Comment: 13 pages, 11 figures; accepted for publication in Ap

Bibliography of the Monogenetic Trematode Literature of the World, 1758 to 1969

In preparing this bibliography we have attempted to collect all literature references pertaining to the Monogenea. Accordingly it represents an up-to-date (through September 1969) guide to the literature of these parasites, and is of maximum scope, including not only taxonomic literature but also references to ecological and physiological studies on Monogenea as well as reports of preferred methods of treating infestations of these parasites

High-Frequency InAIAs/InGaAs Metal-Insulator-Doped Semiconductor Field-Effect Transistors (MIDFETs) for Telecommunications

Contains an introduction and reports on experiments and device results.Joint Services Electronics Program Contract DAAL03-89-C-0001Charles S. Draper Laboratory Contract DL-H-40418