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Padrões de eficiencia energetica para equipamentos eletricos de uso residencial / Energy efficiency standards for residential appliancesMelo, Conrado Augustus de 07 August 2009 (has links)
Orientador: Gilberto de Martino Jannuzzi / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-14T04:11:52Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: Os padrões de eficiência energética são mecanismos de política pública responsáveis por significativas economias de energia em muitos países. Em 2007, foram lançadas no Brasil, as primeiras regulamentações específicas que estabeleceram padrões mínimos de eficiência energética para refrigeradores e aparelhos de ar condicionado. Porém, a ausência de procedimentos de avaliação dos impactos destes padrões no consumo de energia do país dificulta uma abordagem mais específica da contribuição da eficiência energética no planejamento energético. Esta tese propõe uma metodologia para estimar os impactos do estabelecimento de padrões de eficiência energética para refrigeradores, aparelhos de ar condicionado, televisores e lâmpadas. São avaliadas as relações entre custo e eficiência energética sob a perspectiva da sociedade e dos consumidores. É verificada a possibilidade de aumento das restrições dos padrões existentes e a oportunidade de ampliação da abrangência dos padrões para outros equipamentos / Abstract: Energy efficiency standards are policy mechanisms responsible for significant energy saving in several countries. In Brasil in year 2007 was launched the first regulation for residential appliances establishing minimum energy efficiency standards for refrigerators and air conditioners. However the lack of impact evaluation of energy savings due the standards adopted do not allow the properly account the contribution of energy efficiency at the national energy planning level. This thesis contributes developing a methodology for estimating the impacts of energy efficiency standards for refrigerators, air conditioners, television sets and light bulbs. A cost-benefit analysis for improved standards is presented under the perspective of the society and the consumers. It is analyzed the possibility of enforce higher levels of existing standards and the possibility of extending the implementation of standards for other equipment / Doutorado / Planejamento de Sistemas Energeticos / Doutor em Planejamento de Sistemas Energéticos
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Joint inversion of Direct Current and Radiomagnetotelluric dataGarcía Juanatey, María de los Ángeles January 2007 (has links)
No description available.
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Joint inversion of Direct Current and Radiomagnetotelluric dataGarcía Juanatey, María de los Ángeles January 2007 (has links)
No description available.
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Conversor de energia luminosa em eletrica para dispositivos de baixa potencia utilizando o efeito piroeletrico do polimero PVDFCárdenas Concha, Viktor Oswaldo 13 December 2004 (has links)
Orientador: João Sinezio de Carvalho Campos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T05:35:30Z (GMT). No. of bitstreams: 1
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Previous issue date: 2004 / Resumo: O polímero polifluoreto de vinilideno (PVDF, PVF2) há décadas é conhecido como um material que possui diversas propriedades (óptica, mecânica e elétrica), se destacando dentre os polímeros, pois raramente se tem um polímero com tantas propriedades. Apesar de conhecido, pouco se tem explorado suas aplicações. Necessitando muito estudo no sentido de dominar e ampliar suas aplicações tecno-científicas. Este trabalho visa mostrar uma de suas aplicações em converter sinais luminosos (proveniente de fonte de luz branca ou sol) em sinais elétricos, podendo assim ser aplicado nos vários campos de sensores e/ou conversores de energia. Como sensores pode-se citar aplicações em detectores de intrusos, controladores de luminosidade de ambientes. Como conversor, convertendo energia luminosa em eletricidade (geradores). Este último caso, especialmente (até o momento) em nano geradores, podendo preencher necessidades onde a massa inercial a ser movimentada deve ser pequena, por exemplo, sondas espaciais, nanomotores e painéis conversores em aplicações espaciais. Dada a importância deste domínio, neste trabalho são apresentados resultados sobre os sinais elétricos gerados em uma fina membrana de PVDF devido ao efeito piroelétrico, causados por fótons de luz branca incidente sobre a membrana de PVDF. O dispositivo montado é basicamente composto por uma membrana de PVDF, um "chopper" (modulador mecânico de luz), um amplificador-casador de impedância e um osciloscópio para monitorar e medir os sinais elétricos gerados. O estudo foi realizado em função dos parâmetros: distância detector-fonte de luz, intensidade (potência) de luz; freqüência de modulação do "chopper" e área de iluminação no sensor. Os resultados mostram que a sensibilidade do sensor é de 8,3 mV/lux; a melhor relação sinal/freqüência é obtida quando o "chopper" opera em de 10 Hz; quando maior a potência da fonte de luz que chega à superfície do sensor maior é o sinal elétrico gerado; tal dependência se observou em função a área iluminada do sensor, como também da proximidade da fonte de luz (mais próximo mais intenso é o sinal elétrico gerado). Além da montagem, princípios de funcionamento e caracterização do sensor e dispositivo, foi realizado o planejamento fatorial no sentido de otimizar os parâmetros e análises dos resultados encontrados / Abstract: The poly(vinyldene fluoride) (PVDF, PVF2) is known as a material that possesses important properties between polymer families (optical, mechanics and electric), in spite of well-known, its properties hasn't been exploring. However, it is necessary a lot of study in the sense of dominate and to enlarge its tecno-scientific applications. This work seeks to show one of the PVDF applications in converting luminous signs (coming of white light source or sun) in electric signs, could be applied in the several fields of sensor or energy converters. As sensor, it can make appointment applications in intruders detectors, atmospheres brightness controllers and many other. As converter, it transforms luminous energy into electricity (generators). In this last case, especially (until the moment) in nano generators, where the inertial mass to be moved should be small, for example space probes, nano motors and panels converters in space applications. Given the importance of this domain, in this work is presented results on the electric signs generated in a fine membrane of PVDF due to the piroelectric effect caused by photons of white light incident on the PVDF membrane. The device design is basically composed by a PVDF membrane, a light mechanical chopper, a matching amplifier of impedance and an oscilloscope monitoring and measuring the generated electric signs. The study is accomplished in function of the parameters: distance light detecting-source, light intensity (potency), chopper modulation frequency and illumination area in the sensor. The results show as, for the device designed used in this work, the sensor sensibility is 8 mV/lux; the best relationship signal/frequency is when the chopper operates in 10Hz; for larger potency of the light source that arrives to the bigger sensor surface is the generated electric sign, such dependence was also observed in relation the illuminated area of the sensor, as well as of the proximity of the light source (eloser more intense is the generated electric signal). The same time these experiments, beyond the device, operation and sensor characterization, an factorial design was carried out to optimizer the parameters and analyses of the found results / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química
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High resolution electrical characterization of III-V materials and devicesDouheret, Olivier January 2004 (has links)
The continuing shrinkage of semiconductor devices towards nanoscale features and increased functionality has prompted a strong need for high-resolution characterization tools capable of mapping the electrical properties with nanoscale lateral resolution. In this regard, scanning capacitance microscopy (SCM) scanning spreading resistance microscopy (SSRM) and Kelvin probe force microscopy (KPFM) have emerged as powerful techniques. This thesis focuses on new applications of these techniques for the electrical characterization of III-V materials, devices and low-dimensional systems. One example is the investigation of GaAs/AlGaAs buried-heterostructure lasers with cross-sectional SCM. Several important issues have been addressed: nanoscale contrast related to local band structure, characterization of interfaces and evaluation of electrical properties of the regrown layers. These investigations demonstrate the ability of SCM for reliable, non-destructive and high resolution analysis of opto-electronic devices. Applications of SCM and SSRM as potential in-line evaluation tool for III-V processing are demonstrated. In this scope, the first work deals with the characterization of ion beam implanted InP, a promising approach to achieve ultrashort carrier lifetimes. The changes in the local electrical properties of this material induced by annealing are tracked. SCM and SSRM measurements were crucial in identifying the local regions of different conductivity due to the non-uniform damage profiles. The results are correlated with those obtained by complementary structural, electrical and optical characterization. The second work in this category establishes the utility of SCM for evaluating the impact of dry etching on the electrical properties of InP. The highly conductive nature of the near surface damaged layer and its subsequent recovery upon annealing is evidenced. A striking correlation between the SCM signal distributions and the ideality factors of macroscopic Schottky contact is observed. The last part deals with the electrical characterization of low-dimensional systems using SCM, SSRM and KPFM. The challenging issues motivating this work are the detection and quantification of confined carriers, the determination of band-offsets and the determination of the spatial resolution of the technique employed. The ability of SCM, SSRM and KPFM to detect carriers accumulated in InGaAs/InP quantum wells (QWs) is demonstrated. In each of these techniques, the physical mechanisms behind the contrast characteristic obtained at QWs are elucidated. The specific issues relating to the determination of the band-offsets are discussed. A new method to determine the "electrical" spatial resolution of SCM and SSRM is addressed using quantum well structures with varying inter-well spacings. Using commercial probes, sub-30 nm and sub-5 nm lateral resolution are determined for SCM and SSRM, respectively. The experimental conditions to perform high resolution measurements are identified.
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High resolution electrical characterization of III-V materials and devicesDouheret, Olivier January 2004 (has links)
<p>The continuing shrinkage of semiconductor devices towards nanoscale features and increased functionality has prompted a strong need for high-resolution characterization tools capable of mapping the electrical properties with nanoscale lateral resolution. In this regard, scanning capacitance microscopy (SCM) scanning spreading resistance microscopy (SSRM) and Kelvin probe force microscopy (KPFM) have emerged as powerful techniques. </p><p>This thesis focuses on new applications of these techniques for the electrical characterization of III-V materials, devices and low-dimensional systems. One example is the investigation of GaAs/AlGaAs buried-heterostructure lasers with cross-sectional SCM. Several important issues have been addressed: nanoscale contrast related to local band structure, characterization of interfaces and evaluation of electrical properties of the regrown layers. These investigations demonstrate the ability of SCM for reliable, non-destructive and high resolution analysis of opto-electronic devices. </p><p>Applications of SCM and SSRM as potential in-line evaluation tool for III-V processing are demonstrated. In this scope, the first work deals with the characterization of ion beam implanted InP, a promising approach to achieve ultrashort carrier lifetimes. The changes in the local electrical properties of this material induced by annealing are tracked. SCM and SSRM measurements were crucial in identifying the local regions of different conductivity due to the non-uniform damage profiles. The results are correlated with those obtained by complementary structural, electrical and optical characterization. The second work in this category establishes the utility of SCM for evaluating the impact of dry etching on the electrical properties of InP. The highly conductive nature of the near surface damaged layer and its subsequent recovery upon annealing is evidenced. A striking correlation between the SCM signal distributions and the ideality factors of macroscopic Schottky contact is observed. </p><p>The last part deals with the electrical characterization of low-dimensional systems using SCM, SSRM and KPFM. The challenging issues motivating this work are the detection and quantification of confined carriers, the determination of band-offsets and the determination of the spatial resolution of the technique employed. The ability of SCM, SSRM and KPFM to detect carriers accumulated in InGaAs/InP quantum wells (QWs) is demonstrated. In each of these techniques, the physical mechanisms behind the contrast characteristic obtained at QWs are elucidated. The specific issues relating to the determination of the band-offsets are discussed. A new method to determine the "electrical" spatial resolution of SCM and SSRM is addressed using quantum well structures with varying inter-well spacings. Using commercial probes, sub-30 nm and sub-5 nm lateral resolution are determined for SCM and SSRM, respectively. The experimental conditions to perform high resolution measurements are identified.</p>
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Elektrisch-thermisch-mechanisch gekoppelte Simulation an den Beispielen eines Aktuators und eines SteckersSteinbeck-Behrens, Cord 23 June 2015 (has links) (PDF)
In einer Einleitung werden verschiedene Möglichkeiten der Kopplung unterschiedlicher physikalischer Domänen diskutiert. Begriffe wie Kopplung auf Systemebene über Terminals und auf Feldebene über Lastvektor oder Matrixkopplung werden zugeordnet. Wie diese Kopplungsmöglichkeiten sich in der ANSYS Simulationsumgebung wiederfinden, wird aufgezeigt. Am Beispiel eines Akuators wird erläutert, welche physikalischen Domänen gekoppelt betrachtet werden müssen, um die hier vorhandenen temperaturabhängigen Materialeigenschaften zu berücksichtigen. In einem Beispiel zu einer Steckverbindung wird aufgezeigt, wie eine vom Kontaktdruck abhängige Leitfähigkeit berücksichtigt wird und Ergebnisse aus dieser Simulation werden diskutiert.
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Quantização de Landau para quadrupolo elétrico.Melo, Jilvan Lemos de 22 October 2010 (has links)
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Previous issue date: 2010-10-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work we discuss the importance of the quantum phases using the Aharonov-Bohm Effect for charged particles and neutral particles with magnetic dipole moment(Aharonov-
Casher Effect) and electric dipole moment(He-McKellar-Wilkens Effect) and atoms with electric quadrupole moment. It takes advantage of the initial study of such systems to show the emergence of Landau levels in the dynamics of a particle in two situations: when the particle is charged and when it is neutral. In the case of a neutral particle is considered that it possesses electric dipole moment. In addition it is the first time which is approached a neutral atom with electric quadrupole moment. / Neste trabalho discutimos a importância das fases quânticas usando o Efeito Aharonov-Bohm para partículas carregadas e partículas neutras com momento de dipolo magnético (Efeito
Aharonov-Casher) e momento de dipolo elétrico (Efeito He-McKellar-Wilkens), e átomos com momento de quadrupolo elétrico. Tira-se vantagem do estudo inicial de tais sistemas para mostrar a emersão de níveis de Landau na dinâmica de uma partícula em duas situações: quando a partícula está carregada e quando ela é neutra. No caso de uma partícula neutra é considerado que esta possui momento de dipolo elétrico. Além disso é a primeira vez que é abordado um
átomo neutro com momento de quadrupolo elétrico.
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Elektrisch-thermisch-mechanisch gekoppelte Simulation an den Beispielen eines Aktuators und eines SteckersSteinbeck-Behrens, Cord 23 June 2015 (has links)
In einer Einleitung werden verschiedene Möglichkeiten der Kopplung unterschiedlicher physikalischer Domänen diskutiert. Begriffe wie Kopplung auf Systemebene über Terminals und auf Feldebene über Lastvektor oder Matrixkopplung werden zugeordnet. Wie diese Kopplungsmöglichkeiten sich in der ANSYS Simulationsumgebung wiederfinden, wird aufgezeigt. Am Beispiel eines Akuators wird erläutert, welche physikalischen Domänen gekoppelt betrachtet werden müssen, um die hier vorhandenen temperaturabhängigen Materialeigenschaften zu berücksichtigen. In einem Beispiel zu einer Steckverbindung wird aufgezeigt, wie eine vom Kontaktdruck abhängige Leitfähigkeit berücksichtigt wird und Ergebnisse aus dieser Simulation werden diskutiert.
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Identifiering av lagerströmmar i elmotorer för framdrivning av tunga fordon : Utveckling av metod och programvara för att detektera lagerströmmar / Identification of Bearing Currents in Electric Motors for Heavy Vehicles : Development of Methodology and Software to DetectBearing CurrentsLindström, Jessica January 2023 (has links)
Klimatutmaningar, lagändringar och ett ökat miljötänk har tvingat transportsektorn att ställa om till eldrift. Batterier och elmotorer har utvecklats kraftigt och är nu ett alternativ även för tunga fordon. Ett vanligt förekommande problem med elmotorer i fordon är lagerströmmar, här kallat gnista eller blixthändelser. Dessa uppstår på grund av oönskade urladdningar i motorn och förorsakar skador på lagren i motorn. Syftet med motorlager är att avlasta och minska friktionen kring motoraxeln. För att förebygga problemet och se förbättringar eller försämringar av olika åtgärder som görs krävs att lagerströmmar kan identifieras utifrån mätdata. Detta examensarbete analyserar relevant forskning inom området för att sedan introducera en metod och en algoritm för att identifiera lagerströmmar i samarbete med Scania CV. Algoritmen består av tre olika parametrar som påverkar identifieringen av de oönskade strömmarna på olika sätt. Verktyget lyckades identifierade lagerströmmar i olika mätdata, och hittade skillnader i antalet blixthändelser mellan olika körningar av provobjektet. Dock krävs vidare utveckling av verktyget och möjligheten att bearbeta annan typ av data som exempelvis spänningar i motorn för atthitta bättre samband. / A changing climate, changing laws and an increased environmental consciousnesshas forced the transport sector to transition to electric power. Batteries and electric motors have seen a quick and powerful development which means that they are now an alternative even for heavy vehicles. A common problem with electric motors forvehicles is bearing currents. The bearing currents occur as a result of electrical discharges in the motor and can damage the bearings inside the motor. The purpose of motor bearings is to offload and reduce friction for the motor shaft. To prevent the issue and to see improvements or deteriorations from different preventativemeasures it is critical to be able to identify bearing currents from data. This thesis analyzes relevant research in the area before introducing a method and an algorithm for detecting bearing currents in cooperation with Scania CV. The algorithm is composed of three different parameters which affects the identification in different ways. The tool was able to identify bearing currents from various data and found differences between the number of bearing currents between different test runs of the motor. However, more development of the tool and the possibility to process different kinds of data like voltages inside the motor is needed to be able to find better patterns in the data.
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