Análise de linhas de fita não-homogêneas com camadas dielétricas anisotrópicas

Abstract

Localização de faltas em linhas de transmissão de múltiplos terminais a partir de registros oscilográficos sincronizados via transformada wavelet

The electric energy is essential to the development of modern society and its increasing demand in recent years, effect from population and economic growth, becomes the companies more interested in the quality and continuity of supply, factors regulated by ANEEL (Agência Nacional de Energia Elétrica). These factors must be attended when a permanent fault occurs in the system, where the defect location that caused the power interruption should be identified quickly, which is not a simple assignment because the current systems complexity. An example of this occurs in multiple terminals transmission lines, which interconnect existing circuits to feed the demand. These transmission lines have been adopted as a feasible solution to suply loads of magnitudes that do not justify economically the construction of new substations. This paper presents a fault location algorithm for multiple terminals transmission lines - two and three terminals. The location method is based on the use of voltage and current fundamental phasors, as well as the representation of the line through its series impedance. The wavelet transform is an effective mathematical tool in signals analysis with discontinuities and, therefore, is used to synchronize voltage and current data. The Fourier transform is another tool used in this work for extract voltage and current fundamental phasors. Tests to validate the location algorithm applicability used data from faulty signals simulated in ATP (Alternative Transients Program) as well as real data obtained from oscillographic recorders installed on CHESF s lines.

Distribuição da carga hidráulica em linhas de derivação otimizadas por programação linear

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dimensionamento de sistemas de aterramento em linhas de transmissão para escoamento eficiente de correntes de surtos atmosféricos

This work presents in a simulated environment, to analyze the length of cable needed counterweight connected to ground rod, able to avoid the phenomenon of flashover return, back flashover, the insulator chains of transmission lines consisting of concrete structures when they are subjected to lightning standardized regarding certain resistivity values of some kinds of soil and geometric arrangements of disposal of grounding systems structures

Montagem e operação de um secador pneumático tipo flash

In this work, a pneumatic dryer has been designed and assembled in laboratory scale in order to study and evaluate configurations more efficient for application in drying of important materials of Northeast region in Brazil. The equipment was tested with drying of corn and rice grains, in conditions of temperature and air velocity at 80 oC and 35 m/s, respectively. For this type of dryer, it is recommended to work at temperatures above 200 °C and air velocity with higher dynamic pressure. However, even under operating conditions below what it is recommended, the results obtained with the pneumatic dryer were satisfactory. In addition, experiments of drying were performed by using a cabinet dryer (batch dryer) under the same conditions used in the pneumatic dryer. Flash one curves for the corn were fitted satisfactorily by applying of the Lewis model, while a better agreement was found for rice by using the Page model. The data obtained with both drying processes allowed to compare the performance between pneumatic and batch dryers. In respect to drying rate, the pneumatic dryer presented a similar performance to the batch dryer during processing with corn and a superior performance to the last one during processing with rice. Therefore, it was possible to verify that the pneumatic dryer assembled in this preliminar study can be applied for different materials and under different operating conditions

Montagem e construção de um magnetômetro a efeito Kerr magneto-óptico

n this master s dissertation a Kerr Magneto Optic s magnetometer effect was set up to do characterization of samples type films fine and ultra thin, these samples will be grown after the implementation of the sputtering technique at the magnetism laboratory of of this department. In this work a cooled electromagnet was also built the water and that it reaches close values to 10kOe with a gap of 22 mm including an area of uniform field of 25mm of diameter. The first chapter treats of the construction of this electromagnet from its dimensioning to the operation tests that involve measures of reached maximum field and temperature of the reels when operated during one hour. The second chapter is dedicated to the revision of the magnetism and the magnetization processes as well as it presents a theoretical base regarding the magnetic energies found in films and magnetic multilayer. In the sequence, the third chapter, is especially dedicated the description of the effects magneto opticians the effect kerr in the longitudinal, traverse and polar configurations, using for so much only the classic approach of the electromagnetism and the coefficients of Fresnel. Distinguished the two areas of observation of the effect regarding thickness of the film. The constructive aspects of the experimental apparatus as well as the details of its operation are explained at the room surrender, also presenting the preliminary results of the measures made in one serializes of permalloy films and concluding with the results of the characterization of the first films of iron and permalloy grown here at the theoretical and experimental physics department at UFRN

A montagem e a utilização de lunetas de baixo custo como experiência motivadora ao ensino de astronomia

This work reports on an experience of continual development courses for in-service teachers from some high schools of Bauru's (SP) region, for whom a specific workshop on assembling of refractor telescopes has been carried out in order to supplement their knowledge in astronomy. In the current article, the importance of the practice (or "knowing") in the context of their academic formation is discussed as well as some steps on the assembling of low cost refractor telescopes are described. The main results obtained from the participation of these teachers in the proposed activities are also presented.

Sair curado para a vida e para o bem: diagramas, linhas e dispersão de forças no complexus nosoespacial do Hospital de Caridade Juvino Barreto (1909-1927)

This work has as object of study the Hospital de Caridade Juvino Barreto, nosocomial institution located in the city of Natal (RN), between the Praia de Areia Preta and the Monte Petrópolis, focusing on the period from 1909, the year in which the new hospital building was constructed and opened, and 1927, the date of the transfer of administration of the public domain to the newly created Sociedade de Assistência Hospitalar (SAH). We study the conditions of possibility of the emergence of this hospital space in the urban environment of the capital of Rio Grande do Norte, seeking to understand the different tactics and strategies implemented by the historical subjects involved in the formation of this institution nosocomial. Starting from a corpus of documents consisting of medical memories (with Dr. Januário Cicco as privileged observer), information present in newspapers (the Republic and the Christmas Journa l), photo collection and extensive administrative and legal material (Speeches, Exhibitions, Reports, Laws and Resolutions), we analyzed in detail the medical geography of HCJB, relating the discourses of medicine and geography in choosing the spatial location of the hospital as we examine the architecture of the hospital, its inner spat iality, divisions, forms of space control, and, finally, we discuss the medical practices that took place within it, leading us in this regard, from the experiences of clinical hospital chief, Dr. Januário Cicco, especially the discussion on "ethics" in hospital work. The perception of HCJB as medical nosoespaciality always on the move, incorporated under taxonomic principles based on difference and dispersion forces, led us to articulate it theoretically from the conceptual-methodological arsenal of philosopher Michel Foucault, particularly his reflections of genealogical phase, focusing on the phenomenon of power, a position that allows us to enhance our space-hospital construction, invention, product of power relations, which give the unfinished aspect nosocômio, apparent, always at stake, perpetual non-modeling possibility has previously defined array, establishing it at the field of possible, of virtuality, of power: hospital that could have been and that it was not. Indeed, the investigation of various aspects/elements of hospital space Juvino Barreto revealed us new dimensions of hospital space, far more complex than the simple and the current idea of a place to shelter patients: plasticity and fluidity of space, which is not made to circumscribe the limits of empeiria, engraving up to strength relations fought between different subject; its Constitution as a transitional space, Heterotopic, doing live inside modern elements with premoderns (professional doctors working with religious thought, skeptical of positivist medicine living with the religious faith of the nuns of Santana); the impossibility of thinking hospital space of HCJB while homogeneous unit, static, transistoric, making the spatiality, without considering the profound differences, fractures and dislocations that animated his own existence, multiplying their expressions of identity

Representação de linhas de transmissão por meio de variáveis de estado levando em consideração o efeito da freqüência sobre os parâmetros longitudinais

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

Decomposição modal de linhas de transmissão a partir do uso de duas matrizes de transformação

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

Método da continuação aplicado na análise de contingência de linhas de transmissão

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

Uma estratégia dirigida a modelos e baseada em linguagem de descrição arquitetural para linhas de produtos de software

Model-oriented strategies have been used to facilitate products customization in the software products lines (SPL) context and to generate the source code of these derived products through variability management. Most of these strategies use an UML (Unified Modeling Language)-based model specification. Despite its wide application, the UML-based model specification has some limitations such as the fact that it is essentially graphic, presents deficiencies regarding the precise description of the system architecture semantic representation, and generates a large model, thus hampering the visualization and comprehension of the system elements. In contrast, architecture description languages (ADLs) provide graphic and textual support for the structural representation of architectural elements, their constraints and interactions. This thesis introduces ArchSPL-MDD, a model-driven strategy in which models are specified and configured by using the LightPL-ACME ADL. Such strategy is associated to a generic process with systematic activities that enable to automatically generate customized source code from the product model. ArchSPLMDD strategy integrates aspect-oriented software development (AOSD), modeldriven development (MDD) and SPL, thus enabling the explicit modeling as well as the modularization of variabilities and crosscutting concerns. The process is instantiated by the ArchSPL-MDD tool, which supports the specification of domain models (the focus of the development) in LightPL-ACME. The ArchSPL-MDD uses the Ginga Digital TV middleware as case study. In order to evaluate the efficiency, applicability, expressiveness, and complexity of the ArchSPL-MDD strategy, a controlled experiment was carried out in order to evaluate and compare the ArchSPL-MDD tool with the GingaForAll tool, which instantiates the process that is part of the GingaForAll UML-based strategy. Both tools were used for configuring the products of Ginga SPL and generating the product source code

Uma abordagem anotativa para gerência de variabilidade em linhas de processos de software: concepção, implementação e avaliação

Nowadays, the importance of using software processes is already consolidated and is considered fundamental to the success of software development projects. Large and medium software projects demand the definition and continuous improvement of software processes in order to promote the productive development of high-quality software. Customizing and evolving existing software processes to address the variety of scenarios, technologies, culture and scale is a recurrent challenge required by the software industry. It involves the adaptation of software process models for the reality of their projects. Besides, it must also promote the reuse of past experiences in the definition and development of software processes for the new projects. The adequate management and execution of software processes can bring a better quality and productivity to the produced software systems. This work aimed to explore the use and adaptation of consolidated software product lines techniques to promote the management of the variabilities of software process families. In order to achieve this aim: (i) a systematic literature review is conducted to identify and characterize variability management approaches for software processes; (ii) an annotative approach for the variability management of software process lines is proposed and developed; and finally (iii) empirical studies and a controlled experiment assess and compare the proposed annotative approach against a compositional one. One study a comparative qualitative study analyzed the annotative and compositional approaches from different perspectives, such as: modularity, traceability, error detection, granularity, uniformity, adoption, and systematic variability management. Another study a comparative quantitative study has considered internal attributes of the specification of software process lines, such as modularity, size and complexity. Finally, the last study a controlled experiment evaluated the effort to use and the understandability of the investigated approaches when modeling and evolving specifications of software process lines. The studies bring evidences of several benefits of the annotative approach, and the potential of integration with the compositional approach, to assist the variability management of software process lines

Análise de impacto baseada em rastreabilidade de artefatos para linhas de produto de software

Software Product Line (SPL) consists of a software development paradigm, whose main focus is to identify features common and variability among applications in a specific domain. An LPS is designed to attend all products requirements from its product family. These requirements and LPS may have changes over time due to several factors, such as evolution of product requirements, evolution of the market, evolution of SLP process, evolution of the technologies used to develop the products. To handle these changes, LPS should be modified and evolve in order to not become obsolete, and adapt itself to new requirements. The Changes Impact Analysis is an activity that understand and identify what consequences these changes are cause on LPS. Impact Analysis on LPS may be supported by traceability relationships, which identify relationships between artefacts created during all phases of software development. Despite the solutions of change impact analysis based on traceability for software, there is a lack of solutions for assessing the change impact analysis based on traceability for LPS, since existing solutions do not include estimates specific to the artefacts of LPS. Thus, this paper proposes a process of change impact analysis and an tool for assessing the change impact through traceability of artefacts in LPS. For this purpose, we specified a process of change impact analysis that considers artifacts produced during the development of LPS. We have also implemented a tool which allows estimating and identifying artefacts and products of LPS affected from changes in other products, changes in class, changes in features, changes between releases of LPS and artefacts related to changes in core assets and variability. Finally, the results were evaluated through metrics