10 research outputs found
Six-Port Reflectometer Influence of Q-Points Position in Gamma-Plane on Sidearm Power Detector Error Propagation
No full textSix-Port Reflectometer: Influence of Q-Points Position in Γ−Plane on Sidearm Power Detector Error Propagation
No full text
Combining BIM, GIS, and IoT to Foster Energy Management and Simulation in Smart Cities
No full textThis chapter presents a novel distributed software infrastructure to enable energy management and simulation of novel control strategies in smart cities. In this context, the following heterogeneous information, describing the different entities in a city, needs to be taken into account to form a unified district information model: internet-of-things (IoT) devices, building information model, system information model, and georeferenced information system. IoT devices are crucial to monitor in (near-) real-time both building energy trends and environmental data. Thus, the proposed solution fulfills the integration and interoperability of such data sources providing also a correlation among them. Such correlation is the key feature to unlock management and simulation of novel energy policies aimed at optimizing the energy usage accounting also for its impact on building comfort. The platform has been deployed in a real-world district and a novel control policy for the heating distribution network has been developed and tested. Finally, experimental results are presented and discusse
IoT software infrastructure for Energy Management and Simulation in Smart Cities
No full textThis paper presents an IoT software infrastructure that enables energy management and simulation of new control policies in a city district. The proposed platform enables the interoperability and the correlation of (near-)real-time building energy profiles with environmental data from sensors as well as building and grid models. In a smart city context, this platform fulfills i) the integration of heterogeneous data sources at building and district level, and ii) the simulation of novel energy policies at district level aimed at the optimization of the energy usage accounting also for its impact on building comfort. The platform has been deployed in a real world district and a novel control policy for the heating distribution network has been developed and tested. Results are presented and discussed in the paper
Bancada para ensaios de materiais ferromagnéticos em chapa única sob campos rotacionais
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica.A tese aborda o desenvolvimento e a implementação de uma bancada para ensaios de materiais ferromagnéticos baseada no teste rotacional de chapa única (RSST). A bancada RSST é composta de um quadro magnético, inversores de freqüência, malhas de controle, sensores de campo e de indução magnética, amplificadores de sinais, e, ainda, placas de geração e aquisição de sinais baseadas em computadores pessoais. Uma nova técnica é empregada nesta aplicação na qual os inversores de tensão são comandados por malhas de controle realimentado do tipo modo deslizante. As principais vantagens desta técnica são: capacidade de operação dos inversores em uma ampla faixa de freqüências e amplitudes da tensão de saída; não necessitar de prévio conhecimento do comportamento do material a ser caracterizado e controlar a forma de onda do fluxo magnético na amostra em teste, desde baixas induções até próximo à saturação do material, com baixa distorção harmônica em sinais senoidais. Além disso, a bancada pode aplicar também formas de ondas arbitrárias de indução magnética na amostra. A influência que a blindagem exerce nas medições de campo magnético no dispositivo e as técnicas de medição de indução são analisadas por meio de resultados experimentais e simulações numéricas em 3D
Contribuição à modelagem vetorial da histerese magnética
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica
Integrated Circuit Signal Generation and Detection Techniques for Microwave and Sub-Millimeter Wave Signals
No full textThe unabated reduction of device feature sizes in semiconductor processes, particularly in complementary metal-oxide semiconductor (CMOS) processes, has served as the enabling factor behind integrated electronic systems of ever increasing complexity and speeds. As a result, former niche market applications, such as the global-positioning system (GPS), cellular telephony or powerful general purpose computers, have expanded into the field of consumer electronics with tremendous impact on the daily lives of millions of people. It is, therefore, only logical that the future will bring new applications to the mass market that today only exist as niche applications.
Systems operating in the millimeter wave frequency range are an example of a current niche market, with current research striving to fully integrate such systems using advanced semiconductor processing technology. Electromagnetic waves at these frequencies become comparable in size to the electronics circuits. This opens the possibility for novel design approaches that were traditionally not available to integrated circuit radio-frequency designers. On the other hand, the increase in the number of available devices also brings with it new challenges due to increasing variability in device performance. Self-correcting techniques for integrated circuits that offset this increased variability are therefore also highly desirable.
In this dissertation, we explore the above issues on several fronts. We will first present a phase-locked loop synthesizer that auto-corrects its spurious output tones as an example of circuits that correct for a parasitic effect by leveraging the availability of many active devices to construct a digital feedback loop. We will then focus on the effort to operate CMOS integrated circuits in the terahertz regime by developing a solid design foundation for converting signals to frequencies beyond the maximum power gain frequency〖 f〗_max. We will use the insights gained to develop and explore two designs generating power at these high frequencies as proofs of concept. Finally, we will focus on the passive electromagnetic components of such high frequency systems and present a novel way of designing electromagnetic structures that are comparable to the wavelength size in integrated systems by introducing the third physical dimension into the design process for integrated electromagnetic structures.</p
Cálculo de campos magnéticos considerando histerese
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico.O objetivo deste trabalho é descrever uma metodologia para o cálculo de campo magnético não linear, aplicada no método de elementos finitos em 2D, incluindo na mesma um modelo de histerese vetorial, considerando o campo rotativo e alternado. A formulação faz uso dos vetores de campo globais B, H e M , a qual pode ser combinada com o método de elementos finitos para resolução das equações de Maxwell. A magnetização M é diretamente introduzida na equação que governa o sistema. A equação resultante após aplicação do procedimento de Galerkin é combinada com a equação do circuito e resolvida pelo método de Newton-Raphson. Verifica-se que existe boa concordância entre os resultados simulados e os experimentais considerando os casos: a) eletroimã - barra de ferro; b) quadro de Epstein de 25 cm c) estrutura de ferro (rotor). O processo iterativo apresentou desempenho satisfatório e conclui-se que esta metodologia pode ser uma ferramenta importante para cálculo de campo magnético passo a passo no tempo levando em consideração a histerese
