Impedance Based Monitoring
Mostrando 1-12 de 17 artigos, teses e dissertações.
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1. Electromechanical Impedance - Based Structural Health Monitoring Instrumentation System Applied to Aircraft Structures and Employing a Multiplexed Sensor Array
ABSTRACT: The electromechanical impedance method has been seen as a promising tool for structural health monitoring regarding different types of structures and purposes. Most importantly, this method can be used in real-time applications. Frequently, massive, high-cost, single-channel impedance analyzers are used to process the time domain data, aiming at ob
J. Aerosp. Technol. Manag.. Publicado em: 2015-09
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2. Simulation and manufacturing of a miniaturized exponential UWB TEM horn antenna for UWB radar applications
This paper presents the parameterization of the structure of a miniaturized exponential UWB TEM horn antenna and its effect on the matching impedance and directivity. In addition, a microstrip balun that feeds the antenna was proposed in order to improve the balance, and the return loss for low frequencies. Both the antenna and the microstrip balun were simu
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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3. Sensor químico baseado em microponte de impedância = : Chemical sensor based on impedance microbridge / Chemical sensor based on impedance microbridge
A integração de sistemas microeletrônicos em lab-on-a-chip está sendo cada vez mais necessária para concretizar novas aplicações dentro do emergente campo da microfluídica. Tanto na química quanto na bioquímica e até mesmo na medicina e bioengenharia, a microfluídica evolui conquistando um espaço crescente. Entretanto, desafios tecnológicos res
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 31/07/2012
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4. Architecture of a remote impedance-based structural health monitoring system for aircraft applications
The essence of structural health monitoring (SHM) is to develop systems based on nondestructive inspection (NDI) technologies for continuous monitoring, inspection and detection of structural damages. A new architecture of a remote SHM system based on Electromechanical Impedance (EMI) measures is described in the present contribution. The proposed environmen
J. Braz. Soc. Mech. Sci. & Eng.. Publicado em: 2012
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5. Estimador de variações de tensão de curta duração em sistemas elétricos de potência utilizando estratégias evolutivas. / Estimate short duration voltage variation using evolutionary strategies.
A methodology is herein proposed to estimate Short Duration Voltage Variation (SDVV) in electric power systems, caused by electrical faults. To attain this target, values recorded by measurement equipment in specific sites are used. In fact, there are few power quality meters installed in power networks, due to the high cost of such meters. Although these co
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/09/2011
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6. Development of a methodology for identification of cardiac region in images of electrical impedance tomography of pulmonary perfusion by means of wavelet transform / Desenvolvimento de uma metodologia para identificação de região cardíaca em imagens de tomografia de impedância elétrica de perfusão pulmonar por meio da transformada wavelet
Electrical Impedance Tomography (EIT) is an imaging technique, still in development, which allows imaging of the distribution of conductivity in a cross section of an object under analysis from electrical measures made on its surface. Despite its benefits and advantages over other imaging techniques, its images still do not offer a good spatial resolution. O
Publicado em: 2009
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7. Avaliação do efeito de tratamentos superficiais na resistência à corrosão de magnetos de Nd-Fe-B / Assessment of the effect of surface treatments on the corrosion resistance of Nd-Fe-B Magnets.
Nd-Fe-B magnets produced by powder metallurgy are highly susceptible to corrosion due to their complex microstructure and intrinsic porosity due to their fabrication process. Moreover, these magnets have excellent magnetic properties and find many applications. In the nuclear area, permanent magnets based on rare earth transition-iron-boron (Ne-Fe-B) are use
Publicado em: 2009
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8. Structural health monitoring of composite materials subjected to impacts using the electromechanical impedance technique / Monitoramento de integridade estrutural de materiais compostos sujeitos a impactos empregando a técnica da impedância eletromecânica
Nowadays, composite materials have increasingly replaced traditional materials in applications that require improved performance, safety, economy and durability. Nonetheless, such materials exhibit complex damage mechanisms that cannot be easily detected in early stages. Failures can occur during manufacturing, operation or even in the course of maintenance.
Publicado em: 2008
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9. Uma contribuição aos sistemas de monitoramento de integridade estrutural aplicada a estruturas aeronáuticas e espaciais / A contribution to structural health monitoring systems applied to aeronautic and space structures
Este trabalho apresenta uma contribuição para as técnicas de monitoramento de integridade estrutural (SHM Structural Health Monitoring) de componentes aeronáuticos e espaciais. Desta forma, pretende-se apresentar algumas áreas de atuação ainda pouco exploradas, como aplicações em estruturas mecânicas simples, metodologia de acoplamento de tecnologi
Publicado em: 2008
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10. Real-time detection of pneumothorax using electrical impedance tomography / Detecção de pneumotórax em tempo real através da tomografia de impedância elétrica
Introduction: Pneumothorax is a frequent complication during mechanical ventilation. Electrical impedance tomography (EIT) is a noninvasive tool that allows real-time imaging of regional ventilation. The purpose of this study was to: 1) identify characteristic changes in the EIT signals associated with pneumothoraces; 2) develop and fine-tune an algorithm fo
Publicado em: 2008
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11. Structural damage detection using time series analysis and piezoelectries actuators and sensors / Detecção de danos estruturais usando analise de series temporais e atuadores e sensores piezeletricos
This work proposes a novel approach to detect and locate incipient damage in structures by using only acceleration responses and coupled piezoelectric actuators and sensors. Though the major focus in smart damage detection is given by on the monitoring of the electrical impedance in the frequency domain, the current contribution applies a novel technique bas
Publicado em: 2008
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12. Medição de impedância utilizando sistemas digitais
Conducting measurements is, in the most part of practical situations, essential for scientific research. It is so important, that it can be said, that all areas in engineering are dependent of it. As well known, impedance measurement is a subject of great interest in many application fields, each of which has different demands in terms of accuracy, range, me
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/06/2007