Influence of design parameters on linear induction motor end effect

In this paper, a factor referred to as k(f) for linear induction motor end effect analysis is presented. The mathematical model takes into account the longitudinal entry end effect. The entry end effect produces considerable distortion in magnetic field distribution. It is shown how this influence is derived from the machine-developed force that is calculated through the application of the I-D theory. The k(f) factor establishes the relationship between the longitudinal end effect and machine parameters, mainly the number of magnetic poles, secondary resistivity, and frequency.

Static potential in QED(3) with nonminimal coupling

Here we study the effect of the nonminimal coupling j(mu)epsilon(munualpha)partial derivative(nu)A(alpha) on the static potential in multiflavor QED(3). Both cases of four and two components fermions are studied separately at leading order in the 1/N expansion. Although a nonlocal Chern-Simons term appears, in the four components case the photon is still massless leading to a confining logarithmic potential similar to the classical one. In the two components case, as expected, the parity breaking fermion mass term generates a traditional Chern-Simons term which makes the photon massive and we have a screening potential which vanishes at large intercharge distance. The extra nonminimal couplings have no important influence on the static potential at large intercharge distances. However, interesting effects show up at finite distances. In particular, for strong enough nonminimal coupling we may have a new massive pole in the photon propagator, while in the opposite limit there may be no poles at all in the irreducible case. We also found that, in general, the nonminimal couplings lead to a finite range repulsive force between charges of opposite signs.

Effective action for QED with fermion self-interaction in D=2 and D=3 dimensions

In this work we discuss the effect of the quartic fermion self-interaction of Thirring type in QED in D=2 and D=3 dimensions. This is done through the computation of the effective action up to quadratic terms in the photon field. We analyze the corresponding nonlocal photon propagators nonperturbatively in k/m, where k is the photon momentum and m the fermion mass. The poles of the propagators were determined numerically by using the MATHEMATICA software. In D=2 there is always a massless pole whereas for strong enough Thirring coupling a massive pole may appear. For D=3 there are three regions in parameter space. We may have one or two massive poles or even no pole at all. The interquark static potential is computed analytically in D=2. We notice that the Thirring interaction contributes with a screening term to the confining linear potential of massive two-dimensional QED (QED(2)). In D=3 the static potential must be calculated numerically. The screening nature of the massive QED(3) prevails at any distance, indicating that this is a universal feature of D=3 electromagnetic interaction. Our results become exact for an infinite number of fermion flavors.

Scattering and bound states of spin-0 particles in a nonminimal vector double-step potential

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variações horárias na entrada e saída dos golfinhos-rotadores e sua relação com fatores ambientais, na Baía dos Golfinhos em Fernando de Noronha PE

The dolphins are found in all world s marine environments, except for poles. On Brazil, the major concentration of this animals is on Fernando de Noronha Islands, wich have a tropical climate with two well-defined rainfall seasons: dry and rainy season. The Baía dos Golfinhos, wich is the most crowded piece of dolphins on the archipelago. These research looks for to characterize the circadian rhythms of the spinner dolphin behavior, Stenella longirostris, on the Baía dos Golfinhos occupation, at the Fernando de Noronha islands, Brazil s northeast, according to the fluctuations of environment that they all are inserted. The research was realized daily between 1991 January and 2009 December, with observations from a fixed point up to Mirante dos Golfinhos, located on Baía dos Golfinhos. The data was examined with the PASW Statistics 18 program, up to nonparametric tests, being analyzed on the incoming and out coming time of the spinner dolphins and the relationship with moon phases, the wind incidence, and the rainfall season, the dolphins were inserted. The spinner dolphins diurnal rhythms are influenced by moon phases, the spinner dolphins arrival at Baía dos Golfinhos earlier when it s full moon because of the high luminosity at night cause a bigger food efficiency for these animals. The outgoing time of spinner dolphins didn t show statistic difference between moon phases, despite follows the same pattern for the incoming time. When the spinner dolphins are submitted to bigger wind incidence conditions around the archipelago, the dolphins come early to the Baía dos Golfinhos, since that one is protected from wind that reaches Fernando de Noronha, the spinner dolphins tends to arrive later and leave earlier of the bay because the rain may cause adverse conditions for your rest.

A method for plotting the complementary root locus using the root-locus (positive gain) rules

The root-locus method is a well-known and commonly used tool in control system analysis and design. It is an important topic in introductory undergraduate engineering control disciplines. Although complementary root locus (plant with negative gain) is not as common as root locus (plant with positive gain) and in many introductory textbooks for control systems is not presented, it has been shown a valuable tool in control system design. This paper shows that complementary root locus can be plotted using only the well-known construction rules to plot root locus. It can offer for the students a better comprehension on this subject. These results present a procedure to avoid problems that appear in root-locus plots for plants with the same number of poles and zeros.

Realimentação da derivada dos estados em sistemas multivariáveis lineares usando LMIs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Robust State-Derivative Feedback LMI-Based Designs for Linear Descriptor Systems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

On Complementary Root Locus of Biproper Transfer Functions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento territorial no Rio Grande do Norte: uma identificação de clusters rurais

The general objective of this study is the identification of rural spaces in Rio Grande do Norte through a territorial approach. It looks if there is spatial correlations between municipalities that influence and are influenced by the rural environment, allowing the identification of clusters. To accomplish this objective it`s used, in the methodology, the factor analysis of principal components to achieve the indicators of rurality and territorial development, that deal with four dimensions of analysis: environmental, political-institutional, economical and spatial. Moreover, to identify the spatial correlations structure between municipalities it used the Moran index to both rurality and territorial development, leading to clustering identification. The results show that the rurality is present in most of Rio Grande do Norte municipalities, except in cases like Mossoró, Pau dos Ferros, Caicó and Natal, where can be regional dynamic poles. It is also verified that the more rural municipalities tend to be less developed, according to the territorial development index, and have less correlations with neighboring municipalities

As múltiplas faces da evasão na educação superior a distância: a experiência do curso de tecnologia em gestão ambiental do IFRN em dois pólos de apoio presencial

This research presents a reflection on the dropout rates in higher education courses available through distance education in a context marked by deep changes in various spheres of society and by the uncontrolled growth of this educational method. For this, the object of analysis is related to the reality of students of Technology in Environmental Management offered by the Instituto Federal de Educação, Ciência e Tecnologia, Rio Grande do Norte (RN), Brazil, through the distance education in presence support poles located in Mossoró (RN) and Martins (RN). In this field research development several strategies of data collection are used, such as participant observation of reality; analysis of documents related to distance education and to the classes in Technology in Environmental Management; questionnaires answered by students who dropped the course. The results of such research enable us to say that the dropout rates in distance higher education is mainly referred to the consequences of a combination of aspects involved in the course development, personal difficulties faced by students during the period they attend the lessons and elements inherent in the context in which the course and students are inserted. Nevertheless there are specific situations in which the student may drop the program due to the influence of a single aspect, whether it is inherent in the development of the course, a personal situation, or even a factor determined by the context in which the course or the student belongs to

Mortalidade infantil em município do interior do estado de São Paulo

Considerando que a mortalidade infantil é indicador dos níveis de saúde da população, realizamos este trabalho, cujo objetivo foi identificar as causas de mortalidade infantil no ano de 1998 em Botucatu. O coeficiente de mortalidade infantil obtido foi 12/1000 NV, com maior participação dos óbitos neonatais - 8,3/1000 NV A maior parte dos óbitos foi classificada como reduzível ou parcialmente reduzível, mas a atenção necessária para viabilizar tal redução foi variada. Dos óbitos ocorridos, 21,7% eram inevitáveis, evidenciando que para redução dos índices de mortalidade infantil deveremos continuar investindo na qualidade da assistência à saúde e melhoria das condições de vida da população.

Anatomia de raízes de nove espécies de Bromeliaceae (Poales) da região amazônica do estado de Mato Grosso, Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Razão eletromiográfica de músculos estabilizadores do ombro durante a execução de exercícios com haste oscilatória

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O sobre-sinal e a resposta inversa em sistemas de controle lineares contínuos no tempo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)