PI Stabilization of a Class of Time Delay Systems

In this paper we use the Hermite-Biehler theorem to establish results for the design of proportional plus integral (PI) controllers for a class of time delay systems. We extend results of the polynomial case to quasipolynomials using the property of interlacing in high frequencies of the class of time delay systems considered. A signature for the quasipolynomials in this class is derived and used in the proposed approach which yields the complete set of the stabilizing PI controllers.

Stochastic Stability for Markovian Jump Linear Systems Subject to a Crucial Failure Event

This paper is concerned with the stability of discrete-time linear systems subject to random jumps in the parameters, described by an underlying finite-state Markov chain. In the model studied, a stopping time τ Δ is associated with the occurrence of a crucial failure after which the system is brought to a halt for maintenance. The usual stochastic stability concepts and associated results are not indicated, since they are tailored to pure infinite horizon problems. Using the concept named stochastic τ-stability, equivalent conditions to ensure the stochastic stability of the system until the occurrence of τ Δ is obtained. In addition, an intermediary and mixed case for which τ represents the minimum between the occurrence of a fix number N of failures and the occurrence of a crucial failure τ Δ is also considered. Necessary and sufficient conditions to ensure the stochastic τ-stability are provided in this setting that are auxiliary to the main result.

Invariance for Impulsive Control Systems

In this article, we provide invariance conditions for control systems whose dynamics are given by measure driven differential inclusions. The solution concept plays a critical role in the extension of the conventional conditions for the impulsive control context. A couple of examples illustrating the specific features of impulsive control systems are included.

An Improved Design Procedure for LCC Resonant Filter of Dimmable Electronic Ballasts for Fluorescent Lamps, Based on Lamp Model

This paper presents an improved design methodology for determining the parameters used in the classical Series-Parallel Loaded Resonant (SPLR) filter employed in the switching frequency controlled dimmable electronic ballasts. According to the analysis developed in this paper, it is possible to evaluate some characteristics of the resonant filter during the dimming process, such as: range of switching frequency, phase shift and rms value of the current drained by the resonant filter + fluorescent lamp set.

A fast electric load forecasting using adaptive neural networks

This work presents a procedure for electric load forecasting based on adaptive multilayer feedforward neural networks trained by the Backpropagation algorithm. The neural network architecture is formulated by two parameters, the scaling and translation of the postsynaptic functions at each node, and the use of the gradient-descendent method for the adjustment in an iterative way. Besides, the neural network also uses an adaptive process based on fuzzy logic to adjust the network training rate. This methodology provides an efficient modification of the neural network that results in faster convergence and more precise results, in comparison to the conventional formulation Backpropagation algorithm. The adapting of the training rate is effectuated using the information of the global error and global error variation. After finishing the training, the neural network is capable to forecast the electric load of 24 hours ahead. To illustrate the proposed methodology it is used data from a Brazilian Electric Company. © 2003 IEEE.

Integration of the dispersed generators in the distribution management system

Since the 80s huge efforts have been made to utilize renewable energy sources to generate electric power. An important issue about using renewable energy sources is a Distribution Management System (DMS) in presence of dispersed generators. This paper reports some aspects of integration of the dispersed generators in the DMS. Besides, an investigation of impact of the dispersed generators on the overall performances of the distribution systems in steady state is performed. In order to observe losses in the distribution networks with dispersed generators, several loss allocation methods are applied. Results obtained from case study using IEEE test network, are presented and discussed. © 2003 IEEE.

Transient stability analysis of electrical power systems using a neural network based on fuzzy ARTMAP

This work presents a methodology to analyze transient stability for electric energy systems using artificial neural networks based on fuzzy ARTMAP architecture. This architecture seeks exploring similarity with computational concepts on fuzzy set theory and ART (Adaptive Resonance Theory) neural network. The ART architectures show plasticity and stability characteristics, which are essential qualities to provide the training and to execute the analysis. Therefore, it is used a very fast training, when compared to the conventional backpropagation algorithm formulation. Consequently, the analysis becomes more competitive, compared to the principal methods found in the specialized literature. Results considering a system composed of 45 buses, 72 transmission lines and 10 synchronous machines are presented. © 2003 IEEE.

Utilização de índices de estabilidade transitória para a avaliação de segurança dinâmica

Indices that report how much a contingency is stable or unstable in an electrical power system have been the object of several studies in the last decades. In some approaches, indices are obtained from time-domain simulation; others explore the calculation of the stability margin from the so-called direct methods, or even by neural networks.The goal is always to obtain a fast and reliable way of analysing large disturbance that might occur on the power systems. A fast classification in stable and unstable, as a function of transient stability is crucial for a dynamic security analysis. All good propositions as how to analyse contingencies must present some important features: classification of contingencies; precision and reliability; and efficiency computation. Indices obtained from time-domain simulations have been used to classify the contingencies as stable or unstable. These indices are based on the concepts of coherence, transient energy conversion between kinetic energy and potential energy, and three dot products of state variable. The classification of the contingencies using the indices individually is not reliable, since the performance of these indices varies with each simulated condition. However, collapsing these indices into a single one can improve the analysis significantly. In this paper, it is presented the results of an approach to filter the contingencies, by a simple classification of them into stable, unstable or marginal. This classification is performed from the composite indices obtained from step by step simulation with a time period of the clearing time plus 0.5 second. The contingencies originally classified as stable or unstable do not require this extra simulation. The methodology requires an initial effort to obtain the values of the intervals for classification, and the weights. This is performed once for each power system and can be used in different operating conditions and for different contingencies. No misplaced classification o- - ccurred in any of the tests, i.e., we detected no stable case classified as unstable or otherwise. The methodology is thus well fitted for it allows for a rapid conclusion about the stability of th system, for the majority of the contingencies (Stable or Unstable Cases). The tests, results and discussions are presented using two power systems: (1) the IEEE17 system, composed of 17 generators, 162 buses and 284 transmission lines; and (2) a South Brazilian system configuration, with 10 generators, 45 buses and 71 lines.

Morphologic and Cytogenetic Description of the Small Red Brocket (Mazama bororo Duarte, 1996) in Brazil

We evaluated morphological and cytogenetic data for three animals similar to the species of deer previously described as the Small Red Brocket (Mazama bororo Duarte, 1996). We compared these animals with five M. americana, five M. nana and three hybrids between M. americana and M. nana. The M. bororo chromosomes can be standardized as follows : 8 group A chromosomes (large bi-armed) ; 2 group C chromosomes (small bi-armed) ; 4 group D chromosomes (large acrocentric) ; and 18 group E chromosomes (small acrocentric). There were great differences between this karyotype and those of M. nana and M. americana. With respect to external morphology, the animals in the present study had some similarities to M. americana and M. nana and great similarities with their hybrids. Most of the body measurements of M. bororo were significantly different from those of M. americana and M. nana, but similar to those of the hybrids. Mazama bororo is distributed in the last remnants of the Atlantic forest, extending from the southeastern part of the State of São Paulo to the northeastern part of the State of Paraná, Brazil. The rapid destruction of the Atlantic Forest requires urgent conservation measures for the species.

Influência da combinação e modernização dos sistemas que integram o GNSS no georreferenciamento de imóveis rurais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

O tipo penal de disparo de arma de fogo como espécie dos delitos contra a incolumidade pública: uma antecipação de tutela penal legitimável

Pós-graduação em Direito - FCHS

Convergência digital para apoio ao ensino de libras, com ênfase na web e no sistema brasileiro de tv digital

Pós-graduação em Ciência da Computação - IBILCE

As Políticas Públicas para a promoção da igualdade racial no contexto de Presidente Prudente

This work aims at presenting the historical and social path traversed in Brazil since slavery until the implementation of affirmative public policies to promote racial equality, at the local level, in the municipality of Presidente Prudente-SP. Therefore, the starting point was the equal rights guaranteed by the Constitution. As a result, there was a brief historical path of national trajectory, starting from slavery to the so-called cordial racism, seeking to demonstrate the route of racial discrimination in the country. Later, we made notes about the necessity and debate on public policy statements of various fields, were made explicit in the text and the articles of the Constitution which prescribe the crime of racism and some of the situations that were highlighted in the national media. The focus in the city of Presidente Prudente was through historical research, interviews, photographic records and documents that informed about the presence of black people in the city. From these data, based on previous research, it was possible to trace the formation and development of the Black Movement in the city and thus point the way to the formation of this City Council for Racial Equality and the need for application of affirmative action policies for the municipality by hereby. Data from the 2000 Census and 2010 indicate the demand of Presidente Prudente as the percentage of blacks self-declared grew this decade. The main demands are paring the areas of Health since the rate of black women Administrative Region (RA) of Presidente Prudente who die in puerperium and high; Education through enhanced, by the Municipal Education Law No. 10,639, and due attention to african-Brazilian culture by respecting the religious manifestations of African origin among others... (Complete abstract click electronic access below)

A disciplina Língua Brasileira de Sinais nos currículos dos cursos de Pedagogia

Brazilian Sign Language signature in the pedagogy courses curricula. In 2002, the Law nº 10.436 was published determining the obligation of offering the Brazilian Signal Language (Libras) signature in all teaching graduation courses. Considering this measure, it was searched to characterize how the public Higher Education Institutions (HEI) in the States of Paraná and São Paulo are organizing the signature in Pedagogy courses. The curriculum analysis developed showed that most of the public HEI’s in the State of Paraná provides its inclusion, while in the State of São Paulo the estimate is 60%. Most of the syllabus covers topics including deaf students, deaf culture and Libras linguistic aspects.

Educação e políticas públicas para o idoso

The ‘Estatuto do Idoso’ (senior citizen statute), Brazilian federal law promulgated in 2003, defines senior citizen as the person with 60 years old, or more. Revered as a landmark recognition of the senior´s rights, it guarantees, among others, the right of education. According to the statutory provisions, the education is personal right of the elderly person and must be assured with absolute priority by the State, the family, the society, as well by entities. However, in practice, just few senior citizens enjoy the right of education, since this policy has not been developed with focus in the old age, since educational practices are aimed, in most cases, to the younger age groups. Nevertheless, some initiatives seek to invest in the education for the elderly, like happens with the University of the Third Age (U3A). Although this kind of initiatives have been reason of celebration such projects should be enforced and consolidated as an object of better political investment to enlarge the access to the education right to the senior citizens in general. Due to the visibility achieved by the senior population, a possible way to the establishment of services in the area of education, would be the formation of partnerships between educational institutions that understand old age as a potential expansion of cultural goods and production of knowledge.