Teorias de potência conservativa e instantânea: análise comparativa

Pós-graduação em Engenharia Elétrica - FEB

Estudo de um método automatizado para o cálculo da profundidade de visualização dos equipamentos de ultrassonografia

Ultrasound is the term that describes the sound waves with higher frequencies than human hearing. Ultrasound used in medical diagnosis is a modality based on the use of sound energy and the acoustic properties of the various parts of the body to produce images of stationary and moving tissues. However, despite the ease of use and security that this modality offers for not using ionizing radiation, one should ensure the accuracy and optimum performance of the equipment, which results in precise diagnoses. To accomplish that, periodic quality control tests must be performed, which include: physical and mechanical inspection of the equipment, image uniformity, depth of penetration/visualization, accuracy of distances, axial and lateral resolution, dead zone and doppler sensitivity. This work intends to study a computerized method for calculating the depth of penetration of ultrasound, comparing it to the observerdependent method currently used. The images were collected during the quality control tests of ultrasound equipment. The results of the comparison between the visual and computerized methods were not conclusive for selecting the safest methodology for obtaining the depth of visualization

Controle de qualidade em equipamentos mamográficos

Nowadays the mammography is the most effective way of revealing early breast cancer. The image in this kind of exam is gotten trough a x-ray sheaf of low energy, however, the suitable visualization of the interesting structures by the radiologist is not always possible due several factors that appears since the mamma composition until the equipments limitation. The regulation 453/98 sets quality control tests and limits of acceptation that guarantee a good development of the mammographys. The purpose of this study is the 3D principle ( Diagnostic, Dose and Dollar), that means, an improved diagnosis, a dose reduction in the patient and a cost decrease for the Institution. In this study was made the quality control tests set by the Regulation in two mammography equipments from Hospital das Clínicas da Faculdade de Medicina de Botucatu (HCFMB - UNESP). The results reached in this research were used in the renovation process of quality stamp in mammography granted by Colégio Brasileiro de Radiologia (CBR) to the diagnosis by image from the HCFMB – UNESP

Fluxo institucional de resíduos de equipamentos elétricos e eletrônicos e identificação de seus potenciais impactos ambientais e na saúde

A preocupação ambiental em relação aos resíduos de equipamentos elétricos e eletrônicos (REEE) vem crescendo muito nos últimos anos devido à presença de substâncias perigosas que podem causar danos ao ambiente e à saúde. O trabalho teve por objetivo investigar o destino de REEE gerados no Campus Quadrilátero da Saúde/Direito (CQS/D) da Universidade de São Paulo (Faculdade de Medicina, Faculdade de Saúde Pública, Escola de Enfermagem, Instituto de Medicina Tropical e Faculdade de Direito), a partir do momento em que os mesmos deixam as dependências da Instituição e identificar potenciais riscos à saúde e ao ambiente, decorrentes das atuais ações de gerenciamento dos REEE nas unidades estudadas. A pesquisa desenvolveu-se em 3 etapas: a) pesquisa bibliográfica e documental; b) visitas às unidades que compõem o CQS/D, e identificação de cinco intituições filantrópicas como principais destinos; c) visitas aos locais identificados para investigar as atividades desenvolvidas para a recuperação de equipamentos, componentes ou materiais recicláveis, com base em um formulário desenvolvido. Adicionalmente, foram realizadas visitas a outros quatro locais de destino de REEE. Foi identificado que as etapas realizadas nas instituições são: recebimento, teste, conserto e desmontagem manual e que o destino dos REEE pode ser considerado problemático, já que os rejeitos acabam sendo descartados como resíduo comum, podendo causar danos ao ambiente e à saúde. Além disso há riscos ocupacionais, pois os trabalhadores, além de não utilizarem equipamentos de proteção individual necessários, nem sempre recebem capacitação para exercer suas funções

Eficiência energética em uma indústria madeireira

In wood processing industries, which use electrical equipment in the production process, in most cases these are badly scaled or operate under inadequate conditions, resulting directly in industrial energy efficiency, which proves important because besides having technological innovation, also with practices and policies, aims to decrease power consumption. So in a wiring project should take into account the variables that influence energy efficiency. Thus this work has been reviewed and subsequently calculated some of these variables, such as active power, power factor and demand for the entire industry (global) and also for specific equipment, the chipper. The network analysis was performed in a wood processing industry in the city of Taquarivaí - SP, and evaluated these variables with a network analyzer and also by analysis on energy bills, which were found in both analysis levels below those found in literature. These factors are due to poor design, improper use, storage of equipment or even by characteristic of the production process, ie, the equipment running on empty because of the volatility of production

Controle de qualidade em equipamentos de tomografia computadorizada

The computed tomography, devised by Godfrey Hounsfield and Allan Cormack, is in its fourth decade of the clinical use and has presented to be a very useful tool in the diagnosis of several pathologies. For this reason, its use is increasing each day, due to technological progress since its creation. Due to be more and more utilized, the equipment must be in good operating conditions, because it is subject to variance and wearing, damage the quality of diagnosis. To evaluate whether the performance of the scanner remains constant along the time and the dose received by the patient is within the desired limits, periodic tests of quality control must be performed. For this subject, the regulation 453 (June 01, 1998) was created, which determines the need of the implementation of a program for quality assurance (PGQ), where, in addition to the tests of quality control, are established the necessary measurements for the proper functioning of the equipment, generating a trustworthy diagnosis, reducing the dose for the patient and the costs. In this document, are presented tests of quality control carried out in hospitals of the city of Sao Paulo carried out together with the Technical Section of Applications by Imaging Diagnostic (STADI) of the Institute of Electrotechnics and Energy of the University of São Paulo (IEE/USP)

Aplicação dos conceitos de RCM e a ferramenta FMEA no aumento de confiabilidade em equipamentos de uma indústria química

The growing demand for quality at competitive prices and fast production process put to the test function in the industrial Maintenance. The need for equipment with high availability to fit this fierce competitiveness makes maintenance becomes essentially reliable. Despite this current context, many companies still have an old view of maintenance, focused only on corrective services, and proposals for change are often neglected due to the sense of urgency day to day. Thus, this study aims to demonstrate through theoretical applicability of simple tool, but of great value in increasing reliability within the maintenance sector of an industry, applying the concepts of Reliability Centered Maintenance – RCM and Analysis tool Failure Modes and Effects – FMEA in equipment of a chemical company directly involved in the manufacturing process of the brake fluid, which this product is used in vehicles around the country. That way, you can identify the types, occurrence and criticality of each failure and evaluate assertively decision making for each device, avoiding unnecessary downtime and potential failures of the same

Previsão de vendas para uma indústria de equipamentos pesados: seleção de técnicas e análise

The continuous advance of the Brazilian economy and increased competition in the heavy equipment market, increasingly point to the need for accurate sales forecasting processes, which allow an optimized strategic planning and therefore better overall results. In this manner, we found that the sales forecasting process deserves to be studied and understood, since it has a key role in corporate strategic planning. Accurate forecasting methods enable direction of companies to circumvent the management difficulties and the variations of finished goods inventory, which make companies more competitive. By analyzing the stages of the sales forecasting it was possible to observe that this process is methodical, bureaucratic and demands a lot of training for their managers and professionals. In this paper we applied the modeling method and the selecting process which has been done for Armstrong to select the most appropriate technique for two products of a heavy equipment industry and it has been through this method that the triple exponential smoothing technique has been chosen for both products. The results obtained by prediction with the triple exponential smoothing technique were better than forecasts prepared by the industry experts

Estudo de parâmetros radiométricos e legislação sobre radioproteção em equipamentos de radiodiagnóstico

O uso de radiações ionizantes (R.I.), nas mais variadas atividades tem aumentado nas últimas décadas. Com o avanço tecnológico, novos e sofisticados equipamentos emissores de R.I. tem surgido no cenário nacional, o que torna imperativo a difusão do conhecimento sobre os conceitos de proteção radiológica junto à comunidade em geral, e neste sentido, o curso de física médica desenvolve um importante papel, quer seja no aspecto informativo quanto formativo de cidadãos e profissionais críticos e politicamente corretos, que possam contribuir com as Políticas Públicos dos órgãos normatizadores e fiscalizadores das atividades de vigilância sanitária. Conforme a legislação atual (Resolução SS-625 de 14/12/1994, da Secretaria de Estado da Saúde, e Portaria 453 de 01/06/1998 da Vigilância Sanitária do Ministério da Saúde), todos os serviços que utilizam radiações ionizantes devem realizar testes de avaliação dos parâmetros radiométricos dos equipamentos emissores de R.I., sendo exigidos as medidas de Levantamento Radiométrico das instalações, o Teste de Radiação de Fuga do cabeçote emissor e a implementação de Programa de Garantia de Qualidade dos equipamentos e dos procedimentos radiológicos. Este procedimento tem como objetivo principal a obtenção de imagens radiográficas com qualidade e a segurança de pacientes e profissionais, evitando a exposição desnecessária à radiação de pacientes e profissionais. A correta realização de procedimentos radiológicos além de reduzir a dose nos pacientes também promove significativa diminuição nos custos, por não haver necessidade da repetição dos exames. No Brasil, conforme dados da Secretaria de Atenção à Saúde SAS/MS, atualmente existem instalados 4.469 mamógrafos, 25.930 aparelhos de raios-x médicos, 39.438 aparelhos de raios-x odontológicos e...(Resumo completo, clicar acesso eletrônico abaixo)

Incorporação de um sistema nobreak com ultracapacitor em um microcomputador

The objective of this work is to analyze the viability of incorporation in a microcomputer box of a nobreak with an ultracapacitor as energy storage device, substituting the conventional chemical battery. An advantage of this inclusion is cost reduction because a specific metallic or plastic frame won’t be necessary to protect the components of the nobreak; the microcomputer metallic frame offers the necessary protection for both equipments. Moreover, a large quantity of internal space of microcomputers box isn’t used, and is possible to use it to wrap up the nobreak. This work uses data about average power consumption of microcomputers; operation of switching mode power supplies for microcomputers; electrical and mechanical characteristics of ultracapacitors and operation of power circuits of nobreaks, with the purpose of present a study of energy storage capacity that an ultracapacitor should have to allow a safe switching off of a microcomputer in case of electrical network fail. It was noticed that the use of ultracapacitors is feasible to feed an 180 W load for 75 s, using a capacitive bank with sixteen ultracapacitors, with a total capacitance of 350 F and voltage of 10,8 V. The use of the proposed nobreak increases the reliability of the microcomputer by reducing the probability of user data losses in case of an electrical network fail, offering a high cost/benefit product. The substitution of the battery by an ultracapacitor allows a quick nobreak recharge, with low maintenance costs, since ultracapacitors have a lifetime bigger than batteries; beyond reducing the environmental impact, because they don’t use potentially toxic chemical compounds

Desenvolvimento e validação de método bioanalítico por difusão em ágar para determinação da potência do fenticonazol creme vaginal

O nitrato de fenticonazol é um derivado imidazólico de amplo espectro de ação contra patógenos dermatófitos, como Malassezia furfur e leveduras, a principal delas Candida albicans. É necessário que se possa garantir a qualidade dos medicamentos produzidos. O controle de qualidade é uma ferramenta que assegura a qualidade, eficácia e segurança desses produtos até o momento de sua utilização e faz-se necessário que métodos analíticos sejam desenvolvidos e validados para o doseamento desses fármacos. A grande importância dos métodos microbiológicos utilizados no controle de qualidade de fármacos com atividade antimicrobiana é demonstrar sua atividade biológica por meio de seu efeito inibitório no crescimento de micro-organismo. A diminuição da atividade antimicrobiana ou potência pode indicar alguma alteração sutil na molécula, que é pouco detectável em um método analítico físico-químico. O objetivo deste trabalho foi desenvolver e validar o método microbiológico difusão em ágar para o produto nitrato de fenticonazol creme vaginal. O método de difusão em ágar foi desenvolvido utilizando meio de cultura ágar Sabouraud e cepa de Candida albicans ATCC 64548 como micro-organismo teste. Para o ensaio foi utilizado o delineamento 3 x 3, conforme preconiza a Farmacopeia Brasileira (2010). A validação do método proposto demonstrou linearidade entre os diâmetros dos halos de inibição e o logaritmo da concentração na faixa de 50,0 a 200,0 μg/mL. O método obteve resultados precisos e lineares com r2=1. A exatidão foi comprovada pelo intervalo de tolerância de 98,83%, dentro dos limites permitidos. O método foi validado de maneira satisfatória, podendo ser utilizado em análises do Controle de Qualidade deste fármaco.

Amplificador de potência para baixa frequência

In this work we report the development of a tube amplifier built to be used in magnetic probe diagnostic of plasma. The probe is used to measure the magnetic field in the theta-pinch system presently running in our university. We present the calculations and procedures to determine the configuration of circuits and specify the components of the power supply, the preamp stage and the power stage. The circuit configuration and the characteristics of the components was obtained. A representative model of the system behavior gave the transfer function of the amplifier. Theoretical predictions of frequency response and the feedback effects were compared to the experimental values and showed very good agreement. The amplifier works between a frequency bandwidth of 20 an 30 kHz and supply a maximum power of 12 W

Eficiência energética em ar condicionado e refrigeração através da aplicação da termoacumulação

The use of refrigeration and air conditioning systems is of fundamental importance when it comes to air-conditioning of environments. Also important is the use of electricity for equipments’ operation related to these systems. Due to high cost of charging for this type of energy, factors economy and efficiency occupy key roles among design parameters of a system. One of the ways to get this economy is the use of a technique called thermal storage, or cold storage, which intends to move the required loads during peak time and also their equalizing, so that the energy is transferred from the peak time to non-peak time, thereby reducing the cost of energy consumed. Cold can be stored in the form of ice or ice water. This work aims to perform a technical-economic analysis of a mall located in Vale do Paraíba checking the feasibility of deploying a thermal storage system to achieve an economy in the cost of the energy used by the establishment. Through the parameters measured by the concessionaire of energy we can get the values of energy demand and power consumed, which will serve as basis for calculation for the study. The results obtained allow the development of two alternative proposals to the current configuration, one chosen by the criteria and results presented by technical-economic and energy analysis

Desenvolvimento de um anteprojeto de um sistema de digitalização da proteção e controle aplicada a uma subestação elétrica industrial de alta tensão

The proposed of scanning of an electrical industrial substation HV is associated with a segment of the Electrotechnical area and aims the study and preliminary application of digital technologies in the protection, control, measurement and automation maneuvers aimed at a Industrial Electrical System typical High Voltage. Well intended to supervision, protection and control of major electrical and thermal quantities involved in a substation, such as voltage levels, current, temperature, power factor, loads of transformers and circuit feeders, status of interlocking devices, switching equipment maneuvers, etc

Estudo para determinação da kVp em equipamentos de raios X convencional

The quality assurance control program (QACP) in clinical radiology is very important to acquire, image quality, patient dose reduction and cost for the institution. The verification of the real tension on the x ray tube, it is one of many parameters that may be determined on a QACP. This act on image quality as absorbed dose in patient. Once proved the importance of this fact, this study come up with the determination of tension to any X ray tube used on medical routine, on quick, safe and low cost manner. To reach the aim of this study, the methodology consisted on measuring expose rates (ER) using different thicknesses of copper (Cu) plates like filters and relating these results with Half Layer Value (HLV). Afterwards, the HLV was associated to real tension that was acquired with kilo voltage of peak (kVp) measurers used on clinical routine. So walking in this path, when performed the ER, on any X ray tube, it’s possible acquire the HLV and consequently the real kVp, considering measures obtained before, on the methodology of kVp estimative development