Electromechanical Devices
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Chronic Chagas Cardiomyopathy Patients and Resynchronization Therapy: a Survival Analysis
Abstract Introduction: Chagas disease represents an important health problem with socioeconomic impacts in many Latin-American countries. It is estimated that 20% to 30% of the people infected by Trypanosoma cruzi will develop chronic Chagas cardiomyopathy (CCC), which is generally accompanied by heart failure (HF). Cardiac resynchronization therapy (CRT) m
Braz. J. Cardiovasc. Surg.. Publicado em: 2018-02
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2. Effect of parametric uncertainties on the performance of a piezoelectric energy harvesting device
The use of piezoelectric materials for the development of electromechanical devices for the harvesting or scavenging of ambient vibrations has been extensively studied over the last decade. The energy conversion from mechanical (vibratory) to electrical energy is provided by the electromechanical coupling between mechanical strains/stresses and electric char
J. Braz. Soc. Mech. Sci. & Eng.. Publicado em: 2012
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3. Utilização do elo de corrente continua para o amortecimento de oscilações eletromecanicas em sistemas eletricos de potencia / Use of the direct current link for the electromechanical oscillations damping in electric power systems
This dissertation presents a study about the HVDC (High Voltage Direct Current) link contribution for damping low frequency electromechanical oscillations when Electric Energy System suffers small-signal disturbances. The HVDC link components models were included in the Power Flow method as well as the steady-state characteristics of the dynamic devices (cur
Publicado em: 2009
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4. Robust control of FACTS devices to damp oscillations in electric power systems / Controle robusto de dispositivos FACTS para o amortecimento de oscilações em sistemas elétricos de potência
Este trabalho apresenta um método sistemático para projeto de controladores suplementares para um tipo de dispositivo FACTS (o modelo TCSC) para o amortecimento de oscilações em sistemas elétricos de potência. Adota-se uma metodologia previamente desenvolvida para projeto de apenas controladores de tipo PSS. Tal metodologia é fundamentada na teoria de
Publicado em: 2007
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5. Contribuições para melhoria do desempenho e viabilidade de fabricação de scanners indutivos / Contributions to improve the performance, and the manufacture viability of inductive scanners
Scanners are devices that deftects a light beam and converts a spot light in a well controlled amplitude and frequency scan line. Several applications uses the generated pattem to code or decode data, common examples ar,e barcode readers, and laser printers. A light beam can be deftected by different means. In this work, the scanner deftects the light by ref
Publicado em: 2006
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6. Sistema de controle e automação aplicável a secadores em camada fina utilizando-se instrumentos digitais endereçáveis / Automation and control system applicable to thin-layer grain dryer by using digital addressable instruments
Many grain-dryers models with different configurations and applications are encountered worldwide. Among those a thin-layer dryer makes it possible to perform detailed analysis of the drying process. With the results from this analysis results, the drying curves can be modeled and the deep bad grain drying process can be predicted. The thin layer grain dryer
Publicado em: 2006
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7. Obtenção e caracterização de filmes finos de oxido, nitreto e oxinitreto de silicio por deposição ECR-CVD / Synthesis and characterization of oxide nitride and silicon oxynitride thin films by ECR-CVD
In this work, silicon nitride (SixNy), oxide (SiOx) and oxynitride (SiOxNy) thin films obtained by remote plasma chemical vapor deposition (RPCVD) on silicon substrate were studied and characterized for micromachining or micro electro-mechanical system (MEMS) applications. Silicon nitride films (SixNy) were used in suspended structures (membranes and bridges
Publicado em: 2005
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8. Modelagem numerica de problemas de dominios acoplados para aplicação em microsistemas eletromecanicos / Coupled field problems numerical modeling for microelectromechanical systems
Microsistemas eletromecânicos geralmente têm seu princípio de funcionamento baseado na interação entre dois ou mais campos físicos. Para seu projeto são necessárias ferramentas de simulação multi-domínios. Este trabalho visa estudar o fenômeno de acoplamento eletromecânico em microsistemas e construir uma ferramenta de simulação numérica para
Publicado em: 2005
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9. Aplicação de dispositivos FACTS para o amortecimento de oscilações eletromecanicas de baixa frequencia em sistemas de energia eletrica
In this work, the influence of two FACTS devices, the Tiristor Controlled Series Compensator (TCSC) and the Static VAr Compensator (SVC), on power systems low frequency electromechanical oscillations damping, is analyzed by modal analysis, including critical eigenvalues identification and bifurcation analysis. A Power Sensitivity Model is used to represent a
Publicado em: 2001
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10. Surface acoustic wave propagation in Y- and Z-cut 0.67PbMgNbO3–0.33PbTiO3 single crystals
Surface acoustic wave (SAW) propogation in Y-cut and Z-cut relaxor-based 0.67Pb(Mg1∕3Nb2∕3)O3–0.33PbTiO3 (PMN-33%PT) ferroelectric single crystals poled along [001]c cubic direction has been analyzed theoretically. Characteristic curves were obtained for the phase velocity, electromechanical coupling coefficient and PFA of SAW in Y-cut and Z-cut PMN-33
American Institute of Physics.
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11. Cardiac assistance from skeletal muscle: a critical appraisal of the various approaches
We review here various ways in which cardiac assistance might be derived from a patient's own skeletal muscle. Calculations based on experimental data and optimistic estimates of the efficiency of the energy conversions involved suggest that the continuous assist available would be limited to about 2 litres a minute if a muscle were used to energise an elect