Avaliação experimental de medidas de aceleração

Acceleration is a key parameter for engineering and is becoming increasingly important because of the need for companies to become more competitive in the market. Both applying new technologies to their products and optimizing their process lines with predictive maintenance and robotic automation. This study aims to analyze the quality of the signals obtained from a capacitive accelerometer. To do that a test rig was mounted, which consist of a shaker, fed by a signal generator, a linear potentiometer and a capacitive accelerometer; for the signal acquisition was used a acquisition board and the Labview software, in order to integrate twice the signal from the accelerometer and compare it with the sign of the potentiometer. This work also demonstrates the impact of acquired signal processing as well as techniques of pre and post processing of signal via software GNU/Octave

CABARET Casa Noturna e Restaurante

O presente trabalho consiste na elaboração de um projeto de uma casa noturna e restaurante, com uma temática, na cidade de Presidente Prudente. Ele é caracterizado por tratar-se de questões relativas à Arquitetura e Urbanismo, envolvendo os confortos ambientais, especialmente o acústico, e sua implantação em uma cidade média com uma grande população universitária, e que polariza várias cidades da sua região. Além disso, a construção de tal edificação tem como objetivo impulsionar o setor e contribuir para a consolidação do circuito de lazer noturno na cidade. O projeto apresenta dois serviços diferenciados que, no entanto se complementam – os serviços alimentícios e a danceteria. Em um primeiro momento mostram-se integrados, mas podendo funcionar separadamente. Levando em consideração a efemeridade e o dinamismo deste tipo de empreendimento, busca-se, através da arquitetura, solucionar os problemas técnicos referentes à acústica; buscando também atender os anseios e desejos de seus frequentadores, criando espaços de convívio e proporcionando diferentes sensações

Padronização e reprodutibilidade de um teste específico de avaliação da capacidade aeróbia em jogadores de futsal

Introdução: O futsal é uma modalidade esportiva altamente dinâmica e sua prática em nível de rendimento é caracterizada por uma exigência altíssima dos sistemas anaeróbio e aeróbio, sendo o último, responsável por sustentar as altas intensidades exigidas durante a partida. Um exemplo de teste para avaliar a capacidade aeróbia é o “Circuito de Hoff”, porém específico para o futebol. Com a finalidade de elaborar um protocolo de teste específico para o futsal, este estudo procura padronizar o teste “Circuito de Hoff” como uma forma i ndireta de i nvestigar a capacidade aeróbia de atletas dessa modalidade. Objetivo: Padroni zar o “Circuito de Hoff” para avaliação da capacidade aeróbia de jogadores de futsal, determinada pelo teste de lactato mínimo. Metodologia: Participaram do estudo 8 atletas de futsal do sexo masculino (idade: 21,75±2,05 anos) pertencentes a uma equipe universitária de competição do Estado de São Paulo. Inicialmente os participantes passaram por uma avaliação antropométrica e deram início ao um período de 5 dias de familiarização ao Hofffutsal e logo após então realizaram o teste de lactato mínimo no circuito Hofffutsal. Após 7 dias, teste de lactato mínimo no circuito Hofffutsal foi reaplicado para a verificação da reprodutibilidade (intra-teste). Para análise estatística de normalidade e homogeneidade dos dados foram utilizados os testes Shapiro-Wilks e Levene respectivamente. Para comparação dos resultados foi realizado o teste t de Student pareado e a correlação de Pearson (p<0,05). Resultados: O teste t de Student não encontrou diferenças estatísticas entre os valores de Lac_mín teste x Lac_min Re-teste, e R2 Teste X R2 Re-teste. Apresentou-se valores de 7,75±0,29 mmol/l de lactato mínimo e r2 de 0,94±0,09 para teste e um valor de 7,69±0,29 mmol/l de lactato mínimo ...(Resumo completo, clicar acesso eletrônico abaixo)

O uso de software para estudo de seletividade e coordenação

The present work aims to prepare a study of selectivity and coordination in an isolated electrical system with the aid of computer software PTW (Power Tools for Windows). Based on appropriate protection standards, on equipment data and the survey of the curves of “time versus current” (Time Current Curve – TCC), may be defined protection settings to leave the system selective, coordinated and properly protected. Definitions of adjustments are made taking into account the data of, so called, thermal curves of the equipment, which take into account the rated current and the supportability of short-circuit current of the equipment and cables involved in the installation in question. For that we use the tools provided by the PTW in which an industrial electrical circuit is simulated, presenting and discussing the results. With that validates the software PTW, taking it as a great tool helper implementation the coordination and selectivity study

A financeirização da moradia e o Programa Minha Casa Minha Vida

This paper has it is hypotesis on the government program “My Home, My Life” and the assumption that it is a public politic attached to the market logic of financialization of the housing. It is understood that this program encourage capital for the main constructors and incorporated of brazilian heritage elite. It also served as well to promote more rentability to international capital and intensified the sociospacial segregration process as real state speculation has been potencialized. This work aims to present and discuss the program contradictions that have been sustained on the speech of wide subsidy offer and habitance construcution for low income workers - month income until three minimum salaries. Documents have shown that in the first phase of the program, habitance construction for this sector of population corresponded only to 5,5% of total habitation deficit. Businessmen on residance civil construction and public politic representatives have confirmed that the program interests are linked to financial market logic.The real benefits are not for low income workers, but for real state agents through extraordinaty profits of land and the so called new medium workers class(worker class C).We will search for embasement on the country history through the different governments and housing policies, in value theory and the concept of land income to understand the financialization process of the housing. We will also analyse oficial documents and the agents speech involved in real state market to show program contradictions and whose the real benefts are for

Avaliação das impedâncias em pontos de acupuntura

An experimental study in dogs was accomplished to evaluate impedances at the acupuncture points and the relative false points. According to the physics concepts and the Ohm’ Law, an electrical circuit was set up to determine the impedance. This circuit was introduced into three experiments in anesthetized dogs with needles at selected points. In the first two experiments, was applied an alternating tension with 200Hz frequency in the circuit and, in the last experiment, the frequency was increased to 10kHz, the tensions and electrical currents were measured between every pair of points for the all experiments. The impedances were calculated with the values obtained by experiments. The analysis of impedance values indicated that there is a coherent relation between the results and the applied frequencies in circuit, so just at high frequency condition admits the correct measurement of total impedance, therefore the last experiment gave the result which agreed with the theory, that the impedances at acupuncture points are lower than the impedances at false points

Controlador PID utilizando microcontrolador PIC

This monograph proposes the implementation of a low cost PID controller utilizing a PIC microcontroller, and its application in a positioning system previously controlled by a dedicated integrated circuit for a positioning system. Applying the closed-loop PID control, the system instability was reduced, and its response was smoother, eliminating vibrations and mechanical wear compared to its response with the dedicated integrated circuit, which has a very limited control action. The actuator of the system is a DC motor, whose speed is controlled by the Pulse Width Modulation (PWM) technique, using a Full-Bridge circuit, allowing the shift of direction of rotation. The utilized microcontroller was the PIC16F684, which has an enhanced PWM module, with its analog converters used as reference and position feedback. The positioning sensor is a multiturn potentiometer coupled to the motor axis by gears. The possibility of programming the PID coefficients in the microcontroller, as well as the adjustment of the sampling rate, allows the implemented system achieving high level of versatility

Sistema de automação residencial controlado via rede doméstica

The present work develops a residential automation system controlled by PIC microcontroller connected to a domestic network using the TCP/IP protocol. This was motivated by the viability of building an automation system to control basic elements of a house with low cost, which cannot be found nowadays. Initially is presented a brief history of the automation systems and an introduction about PIC microcontrollers. Afterwards is presented an overview of the system to be implemented. Then it is shown a suggested circuit and the sensor and actuator elements as well as the software to manage the system, this was all build and test in the laboratory. In the end are the results obtained from the prototype, like the energy consumption, the cost, efficiency and reliability

Dispositivo de microdescargas em gases na pressão atmosférica

Neste trabalho foi desenvolvido um dispositivo de microdescargas em gases à pressão atmosférica para geração de plasma a fim de ser utilizado no tratamento de superfícies. O trabalho foi baseado em um estudo de iniciação científica que aconteceu em duas etapas. Na introdução apresentam-se as motivações do estudo, o dispositivo desenvolvido na primeira etapa do trabalho bem como os primeiros resultados e propostas de melhorias. Definem-se os objetivos da segunda etapa, que contemplam modificações no dispositivo de descarga e na fonte de alimentação. Em seguida são explanados os métodos utilizados para confecção do dispositivo, construção da fonte de alimentação e circuito de fotodetecção para observar as descargas. Apresenta-se o modelo e configurações dos experimentos, os resultados obtidos são expostos e debatidos brevemente. Colocam-se as conclusões do trabalho e novas propostas de investigação e melhoramentos para o estudo das microdescargas. Seguem-se os agradecimentos aos envolvidos no projeto e, por fim, a bibliografia utilizada

Projeto de um Multiplicador Divisor Anal´ogico em tecnologia CMOS para uso em controlador fuzzy tipo-2 intervalar

The main objective of the presented study is the design of a analog multiplier-divider as integrant part of the type-reducer circuit of type-2 fuzzy controller chip. The proposed circuit is a multiplier/divider which operates in current mode, in the CMOS technology with a supply voltage of 1.8 V.The circuit simulation was performed in PSPICE software with simulation model provided by AMS (Austria Mikro Systems International) in CMOS technology 0.35μm

A influência da temperatura nas impedâncias de sequência de condutores utilizados na rede primária de distribuição

Distribution networks are formed by long lines that carry electricity substations to homes and industries. These lines have associated impedance and depending on operating conditions of the network these impedances may vary. This paper provides a detailed analysis of the effects observed in studies of voltage drop, short circuit and electrical losses, when considered the drivers sequence impedances used in primary distribution network at different temperatures. Therefore, it is initially presented a calculation methodology and details the factors that influence the final values. The methodology presented tackles in a practical way the main factors that directly or indirectly influence the values of the impedances as an emblematic example and will be properly dealt with throughout the paper is the effect of temperature on the values of the sequence impedances. More specifically is dealt with the case of XLPE cables protected, by having a higher maximum operating temperature than the operating temperature of the network. The effects observed in the power flow generated when considering the impedance values at both temperatures were analyzed. The impedance drivers tend to increase with increasing temperature. Thus the impedance of the conductor XLPE protected will tend to be greater for the maximum operating temperature for which the operating temperature of the network, resulting in greater voltage drop and higher electrical losses

Desenvolvimento de um conversor estático PWM para o acionamento de LED’S para iluminação publica

This work deals with the development of a switched-mode power supply circuit based on a Buck topology converter with a Boost Rectifier One-Cycle Control with Power Factor Correction developing, thus, a source of direct current for a module of 50 power LEDs that will be used in a lamp for public street lightning. It is presented, at first, some aspects about the most common technologies used in lamps of public street lightning in Brazil and a comparison with the White LED high power, which is the one that presents itself as the most promising among the existing market. Then it is presented the detailed development of the static converter switched PWM, consisting of a Boost rectifier with power factor correction and methodology of control One-Cycle Control associated with a Buck converter controlled by a PI method that operates as a direct current source . At the end of the simulation results of the circuit through the PSIM software are presented to verify the design behavior

Chaveamento de cargas intermitentes usando sensor de corrente

Due to concerns about rational use of energy, several alternative technologies of power generation appeared, including the conversion of solar energy into electrical energy by photovoltaic panels. In low-income households, the refrigerator represents considerable impact on the electric bill, since it requires constant power given its use in food preservation. It is possible to reduce this share, with the use of an alternative energy source. This work presents a timed switching electronic system, which allows commercial equipment that is not affected by short interruptions in the power supply to use a photovoltaic panel as a source of alternative energy, which usually do not provide energy continuously. Switching is made automatically in case of low incidence of sunlight, and without any form of energy storage. Between each switching, there is a dead time without power supply, therefore preventing the use of synchronizers circuits between the photovoltaic panel and the public power grid. A circuit containing a 80C31 microcontroller is used to control the system’s switching. The photovoltaic panel’s voltage inverter is in H bridge configuration, and is also controlled by the microcontroller through Pulse Width Modulation, which makes use of preprogrammed tables to generate the control signals of the power transistors. Through the use of software simulations, the proposed system was tested, which is capable of supplying intermittent single-phase loads. The simulations indicates that the project developed in this paper can be assembled into a prototype and be tested under real operating conditions, as long as the scaling of components, the characteristics of the photovoltaic panel to be used, and the project involved load are taken into account

Análise de geradores piezelétricos acoplados com circuitos retificadores operando em regime caótico

Pós-graduação em Engenharia Mecânica - FEIS

Análise de conversor multipulso utilizando transformador com culatra intermediária

Pós-graduação em Engenharia Elétrica - FEIS