On the Result of Invariance of the Closure Set of the Real Projections of the Zeros of an Important Class of Exponential Polynomials

In this paper we provide the proof of a practical point-wise characterization of the set RP defined by the closure set of the real projections of the zeros of an exponential polynomial P(z) = Σn j=1 cjewjz with real frequencies wj linearly independent over the rationals. As a consequence, we give a complete description of the set RP and prove its invariance with respect to the moduli of the c′ js, which allows us to determine exactly the gaps of RP and the extremes of the critical interval of P(z) by solving inequations with positive real numbers. Finally, we analyse the converse of this result of invariance.

Fabrico e ensaio balístico em condições reais de conceito melhorado de um projétil de detonação mecânica

A floresta constitui uma das riquezas naturais com maior valor em todo o planeta, assumindo uma vital importância em termos ambientais e económicos, nomeadamente para Portugal. Neste projeto desenvolve-se um potencial meio de combate a incêndios florestais, com base num conceito inovador e complementar aos atuais meios aplicados no combate a este tipo de flagelo. Este projeto de investigação visa o desenvolvimento de um projétil de detonação mecânica, logo inerte, para aplicação no combate a incêndios florestais, e enquadra-se no âmbito de uma parceria alargada de colaboração em I&D entre a Academia Militar e o Instituto Superior Técnico. O conceito deste produto, ao qual foi atribuído o acrónimo: FIREND, foi, inicialmente, desenvolvido no âmbito de um projeto de I&D da Academia Militar. Neste projeto realiza-se o desenvolvimento final do conceito do produto, incluindo a verificação de aspetos chave no projeto mecânico, seleção e aquisição de materiais e fabrico de protótipos para ensaios balísticos em condições reais. Os resultados de funcionalidade e eficiência são apresentados nas fases estabilidade em voo, impacto com o solo, detonação, projeção e dispersão da carga para o exterior e análise de recuperação dos componentes do FIREND, após utilização. Tendo em conta os resultados obtidos relativos ao funcionamento do FIREND durante o disparo do Obus, voo, impacto no solo e detonação e ainda o estado geral dos componentes após os ensaios, pode-se concluir que se trata de um projeto viável.

The zeros and maxima of the Airy function and its first derivative to 25 significant figures.

Mode of access: Internet.

Multi-level zero-inflated Poisson regression modelling of correlated count data with excess zeros

Count data with excess zeros relative to a Poisson distribution are common in many biomedical applications. A popular approach to the analysis of such data is to use a zero-inflated Poisson (ZIP) regression model. Often, because of the hierarchical Study design or the data collection procedure, zero-inflation and lack of independence may occur simultaneously, which tender the standard ZIP model inadequate. To account for the preponderance of zero counts and the inherent correlation of observations, a class of multi-level ZIP regression model with random effects is presented. Model fitting is facilitated using an expectation-maximization algorithm, whereas variance components are estimated via residual maximum likelihood estimating equations. A score test for zero-inflation is also presented. The multi-level ZIP model is then generalized to cope with a more complex correlation structure. Application to the analysis of correlated count data from a longitudinal infant feeding study illustrates the usefulness of the approach.

Estimate for the Number of Zeros of Abelian Integrals on Elliptic Curves

2000 Mathematics Subject Classification: Primary 34C07, secondary 34C08.

On the Zeros of the Solutions to Nonlinear Hyperbolic Equations with Delays

2002 Mathematics Subject Classification: Primary 35В05; Secondary 35L15

Zeros of Sequences of Partial Sums and Overconvergence

2000 Mathematics Subject Classification: 30B40, 30B10, 30C15, 31A15.

Aplicação de tecnologias eletroquímicas (oxidação via radicais hidroxila, oxidação mediada via cloro ativo e eletrocoagulação) para o tratamento de efluentes reais ou sintéticos

In this work the degradation of real and synthetic wastewater was studied using electrochemical processes such as oxidation via hydroxyl radicals, mediated oxidation via active chlorine and electrocoagulation. The real effluent used was collected in the decanter tank of the Federal University of Rio Grande do Norte (ETE-UFRN) of Effluent Treatment Plant and the other a textile effluent dye Ácido Blue 113 (AB 113) was synthesized in the laboratory. In the electrochemical process, the effects of anode material, current density, the presence and concentration of chloride as well as the active chlorine species on site generated were evaluated. Electrodes of different compositions, Ti/Pt, Ti/Ru0,3Ti0,7O2, BDD, Pb/PbO2 and Ti/TiO2-nanotubes/PbO2 were used as anodes. These electrodes were subjected to electroanalytical analysis with the goal of checking how happen the anodic and cathodic processes across the concentrations of NaCl and supporting electrolyte used. The potential of oxygen evolution reaction were also checked. The effect of active chlorine species formed under the process efficiency was evaluated by removing the organic matter in the effluent-ETE UFRN. The wastewater treatment ETE-UFRN using Ti/Pt, DDB and Ti/Ru0,3Ti0,7O2 electrodes was evaluated, obtaining good performances. The electrochemical degradation of effluent-UFRN was able to promote the reduction of the concentration of TOC and COD in all tested anodes. However, Ti/Ru0,3Ti0,7O2 showed a considerable degradation due to active chlorine species generated on site. The results obtained from the electrochemical process in the presence of chloride were more satisfactory than those obtained in the absence. The addition of 0.021 M NaCl resulted in a faster removal of organic matter. Secondly, was prepared and characterized the electrode Ti/TiO2-nanotubes/PbO2 according to what the literature reports, however their preparation was to disk (10 cm diameter) with surface area and higher than that described by the same authors, aiming at application to textile effluent AB 113 dye. SEM images were taken to observe the growth of TiO2 nanotubes and confirm the electrodeposition of PbO2. Atomic Force Microscope was also used to confirm the formation of these nanotubes. Furthermore, was tested and found a high electrochemical stability of the electrode Ti/TiO2-nanotubes/PbO2 for applications such as long-term indicating a good electrocatalytic material. The electrochemical oxidation of AB 113 using Ti/Pt, Pb/PbO2 and Ti/TiO2-nanotubes/PbO2 and Al/Al (electrocoagulation) was also studied. However, the best color removal and COD decay were obtained when Ti/TiO2-nanotubes/PbO2 was used as the anode, removing up to 98% of color and 92,5% of COD decay. Analysis of GC/MS were performed in order to identify possible intermediates formed in the degradation of AB 113.

Sobre a integração indefinida de funções racionais complexas: teoria e implementação de algoritmos racionais

We present indefinite integration algorithms for rational functions over subfields of the complex numbers, through an algebraic approach. We study the local algorithm of Bernoulli and rational algorithms for the class of functions in concern, namely, the algorithms of Hermite; Horowitz-Ostrogradsky; Rothstein-Trager and Lazard-Rioboo-Trager. We also study the algorithm of Rioboo for conversion of logarithms involving complex extensions into real arctangent functions, when these logarithms arise from the integration of rational functions with real coefficients. We conclude presenting pseudocodes and codes for implementation in the software Maxima concerning the algorithms studied in this work, as well as to algorithms for polynomial gcd computation; partial fraction decomposition; squarefree factorization; subresultant computation, among other side algorithms for the work. We also present the algorithm of Zeilberger-Almkvist for integration of hyperexpontential functions, as well as its pseudocode and code for Maxima. As an alternative for the algorithms of Rothstein-Trager and Lazard-Rioboo-Trager, we yet present a code for Benoulli’s algorithm for square-free denominators; and another for Czichowski’s algorithm, although this one is not studied in detail in the present work, due to the theoretical basis necessary to understand it, which is beyond this work’s scope. Several examples are provided in order to illustrate the working of the integration algorithms in this text

“Escritores da liberdade”: histórias reais de jovens que cumpriram medidas socioeducativas em meio aberto no município do Natal/RN

Such work aims to analyze aspects of the lives of adolescents, authors of Infraction, after completion of the Socio-Educational Measures in Half Open (Probation - LA and Services to the Community - PSC) in the city of Natal / RN in 2010. Thus, it become necessary to point out and consider the socio-historical determinations that permeate the lives of these young men, estimating the economic, social, political and historical aspects. We understand that these individuals experience numerous expressions of Social Issues, such as lack of opportunities, violence, unemployment, among others. In the reduction context of the State actions for the social, and investments negligible in public policies. Thus, the research aimed to identify such determinations in the lives of adolescents, young people today, and aimed to know these adolescents and analyze the family situation, socio-economic and political these, after completion of educational measures; and to evaluate the inclusion in school life and in the labor market. Therefore, we used as a methodological way the qualiquantitative research, using the procedure of 4 (four) semi-structured interviews, 9 (nine) analysis processes by configuring so documentary research, through the analysis of reports, processes and monitoring documents. The universe of analysis went adolescents who fulfilled socio-educational measures in liberty in the city of Natal / RN. The sample consisted of nine (9) young, that we follow during the mandatory curricular training, in the period of graduation in Social Work at the Federal University of Rio Grande do Norte, in 2010. The time frame of the research took place between 2010 - 2014. The results of this study indicate that the solution to problems of violence is not the reduction of criminal majority. It is necessary to take actions in ensuring rights and allow other living conditions to the children and adolescents, because, in fact, in the society there is a tendency to regression of rights. We learn that, despite all the difficulties, as: low education, access to the labor market, low income, among others, young people interviewed understand the Socio-Educational Measures such as a watershed in their lives, because, they do not practice more illicit acts, they seek a better life, they have dreams and plans for the future, and they continue writing their histories.

“Escritores da liberdade”: histórias reais de jovens que cumpriram medidas socioeducativas em meio aberto no município do Natal/RN

Such work aims to analyze aspects of the lives of adolescents, authors of Infraction, after completion of the Socio-Educational Measures in Half Open (Probation - LA and Services to the Community - PSC) in the city of Natal / RN in 2010. Thus, it become necessary to point out and consider the socio-historical determinations that permeate the lives of these young men, estimating the economic, social, political and historical aspects. We understand that these individuals experience numerous expressions of Social Issues, such as lack of opportunities, violence, unemployment, among others. In the reduction context of the State actions for the social, and investments negligible in public policies. Thus, the research aimed to identify such determinations in the lives of adolescents, young people today, and aimed to know these adolescents and analyze the family situation, socio-economic and political these, after completion of educational measures; and to evaluate the inclusion in school life and in the labor market. Therefore, we used as a methodological way the qualiquantitative research, using the procedure of 4 (four) semi-structured interviews, 9 (nine) analysis processes by configuring so documentary research, through the analysis of reports, processes and monitoring documents. The universe of analysis went adolescents who fulfilled socio-educational measures in liberty in the city of Natal / RN. The sample consisted of nine (9) young, that we follow during the mandatory curricular training, in the period of graduation in Social Work at the Federal University of Rio Grande do Norte, in 2010. The time frame of the research took place between 2010 - 2014. The results of this study indicate that the solution to problems of violence is not the reduction of criminal majority. It is necessary to take actions in ensuring rights and allow other living conditions to the children and adolescents, because, in fact, in the society there is a tendency to regression of rights. We learn that, despite all the difficulties, as: low education, access to the labor market, low income, among others, young people interviewed understand the Socio-Educational Measures such as a watershed in their lives, because, they do not practice more illicit acts, they seek a better life, they have dreams and plans for the future, and they continue writing their histories.

Um estudo sobre polinômios matriciais

This research work aims to make a study of the algebraic theory of matrix monic polynomials, as well as the definitions, concepts and properties with respect to block eigenvalues, block eigenvectors and solvents of P(X). We investigte the main relations between the matrix polynomial and the Companion and Vandermonde matrices. We study the construction of matrix polynomials with certain solvents and the extention of the Power Method, to calculate block eigenvalues and solvents of P(X). Through the relationship between the dominant block eigenvalue of the Companion matrix and the dominant solvent of P(X) it is possible to obtain the convergence of the algorithm for the dominant solvent of the matrix polynomial. We illustrate with numerical examples for diferent cases of convergence.

Spatial modeling of data with excessive zeros applied to reindeer pellet-group counts

We analyze a real data set pertaining to reindeer fecal pellet-group counts obtained from a survey conducted in a forest area in northern Sweden. In the data set, over 70% of counts are zeros, and there is high spatial correlation. We use conditionally autoregressive random effects for modeling of spatial correlation in a Poisson generalized linear mixed model (GLMM), quasi-Poisson hierarchical generalized linear model (HGLM), zero-inflated Poisson (ZIP), and hurdle models. The quasi-Poisson HGLM allows for both under- and overdispersion with excessive zeros, while the ZIP and hurdle models allow only for overdispersion. In analyzing the real data set, we see that the quasi-Poisson HGLMs can perform better than the other commonly used models, for example, ordinary Poisson HGLMs, spatial ZIP, and spatial hurdle models, and that the underdispersed Poisson HGLMs with spatial correlation fit the reindeer data best. We develop R codes for fitting these models using a unified algorithm for the HGLMs. Spatial count response with an extremely high proportion of zeros, and underdispersion can be successfully modeled using the quasi-Poisson HGLM with spatial random effects.

Software educativo para el décimo año de educación básica: factorización de binomios, trinomios y polinmios

La presente tesina enfoca su interés en las nuevas formas y recursos que, los docentes hoy en día disponen para la enseñanza del algebra en los estudiantes. Hace una reseña del porqué y cómo, mediante la tecnología, se puede obtener mejores resultados dentro del proceso enseñanza aprendizaje, las nuevas tendencias sugieren mejores propuestas en cuanto a textos y materiales de apoyo para el aprendizaje. Proponemos un software educativo dirigido a los alumnos de décimo año de educación básica, con los temas de factorización, para que sea utilizado tanto por el docente, como por el alumno para afianzar los conocimientos adquiridos en el aula y un refuerzo en casa. Además consta de un texto de apoyo al estudiante con ejercicios modelo y ejercicios propuestos para ser trabajados en clase o en casa, de acuerdo a la planificación de clase. Se pretende que este software educativo sea una herramienta de apoyo en los conocimientos, para con los estudiantes