354 resultados para RFID,


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Este projeto teve como principal objetivo continuar o desenvolvimento do quiosque multimédia FNAC. Filial do Grupo Pinault Printemps, a FNAC é líder europeu na distribuição de bens tecnológicos e culturais. Nesta fase do desenvolvimento, o foco do projeto centrou-se na procura da melhor forma de mostrar ao utilizador a localização de um produto na loja FNAC Madeira, expansão das funcionalidades aos restantes produtos e o redesenho da interface do quiosque multimédia FNAC. Por forma a identificar uma forma eficaz de dar a conhecer ao utilizador a localização de um produto dentro da loja FNAC Madeira, foi efetuado um estudo que consistiu em questionários e testes com utilizadores para comparar duas formas de localização, por planta da loja ou por vídeo em tempo real. A primeira versão do quiosque multimédia FNAC apenas possuía suporte a livros, pelo que foi necessário tornar a aplicação o mais abstrata possível por forma a gerar as categorias de produtos em runtime recorrendo a ficheiros XML. Por fim, para redesenhar a interface do quiosque multimédia FNAC, foram efetuadas análises às interfaces da primeira versão, utilizando as heurísticas de Nielsen e os “Principles of good form” de Larry Constantine. Após a fase de análise as interfaces foram redesenhadas tendo por base a análise efetuada, o guia de norma FNAC 2011 e breves testes de usabilidade com utilizadores. Do estudo realizado, na procura pela melhor forma de localização, foram identificados alguns problemas relacionados com a utilização de um vídeo em tempo real para a identificação, tal como as interferências externas por parte dos outros clientes do espaço comercial e foi possível constatar um melhor desempenho e aceitação da localização por planta. A localização por planta mostrou-se suficiente para os utilizadores conseguirem identificar o local onde o produto estava exposto, pois permitia-lhes identificar o local onde encontravam-se e obter uma localização mais precisa do local, necessitando apenas de olhar em volta para conseguir relacionar o que era possível visualizar na planta com aquilo que os rodeava na loja.

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The frequency selective surfaces, or FSS (Frequency Selective Surfaces), are structures consisting of periodic arrays of conductive elements, called patches, which are usually very thin and they are printed on dielectric layers, or by openings perforated on very thin metallic surfaces, for applications in bands of microwave and millimeter waves. These structures are often used in aircraft, missiles, satellites, radomes, antennae reflector, high gain antennas and microwave ovens, for example. The use of these structures has as main objective filter frequency bands that can be broadcast or rejection, depending on the specificity of the required application. In turn, the modern communication systems such as GSM (Global System for Mobile Communications), RFID (Radio Frequency Identification), Bluetooth, Wi-Fi and WiMAX, whose services are highly demanded by society, have required the development of antennas having, as its main features, and low cost profile, and reduced dimensions and weight. In this context, the microstrip antenna is presented as an excellent choice for communications systems today, because (in addition to meeting the requirements mentioned intrinsically) planar structures are easy to manufacture and integration with other components in microwave circuits. Consequently, the analysis and synthesis of these devices mainly, due to the high possibility of shapes, size and frequency of its elements has been carried out by full-wave models, such as the finite element method, the method of moments and finite difference time domain. However, these methods require an accurate despite great computational effort. In this context, computational intelligence (CI) has been used successfully in the design and optimization of microwave planar structures, as an auxiliary tool and very appropriate, given the complexity of the geometry of the antennas and the FSS considered. The computational intelligence is inspired by natural phenomena such as learning, perception and decision, using techniques such as artificial neural networks, fuzzy logic, fractal geometry and evolutionary computation. This work makes a study of application of computational intelligence using meta-heuristics such as genetic algorithms and swarm intelligence optimization of antennas and frequency selective surfaces. Genetic algorithms are computational search methods based on the theory of natural selection proposed by Darwin and genetics used to solve complex problems, eg, problems where the search space grows with the size of the problem. The particle swarm optimization characteristics including the use of intelligence collectively being applied to optimization problems in many areas of research. The main objective of this work is the use of computational intelligence, the analysis and synthesis of antennas and FSS. We considered the structures of a microstrip planar monopole, ring type, and a cross-dipole FSS. We developed algorithms and optimization results obtained for optimized geometries of antennas and FSS considered. To validate results were designed, constructed and measured several prototypes. The measured results showed excellent agreement with the simulated. Moreover, the results obtained in this study were compared to those simulated using a commercial software has been also observed an excellent agreement. Specifically, the efficiency of techniques used were CI evidenced by simulated and measured, aiming at optimizing the bandwidth of an antenna for wideband operation or UWB (Ultra Wideband), using a genetic algorithm and optimizing the bandwidth, by specifying the length of the air gap between two frequency selective surfaces, using an optimization algorithm particle swarm

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Includes bibliography

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The search for more reliable security systems and information management of these systems is leading to a growing progress in new technologies investments that allow the implementation of equipment with a high level of reliability, but also have an agile and practical operation. This led people to turn increasingly looking for home automation systems, enterprise and industry for the automation and integration of their systems. The identification by radio frequency is very widespread today for ensuring both agility in handling records data, the reliability of their identification systems, which are increasingly advanced and less susceptible to fraud. Attached to this technology, the use of the database is always very important for the storage of information collected, the area where the MySQL platform is widely used. Using the open source Arduino platform for programming and manipulation of RFID module and LabVIEW software for the union of all these technologies and to develop a user-friendly interface, you can create a highly reliable access control and agility places a high turnover of people. This project aims to prove the advantages of using all these technologies working together, thus improving a flawed system effectively safety, cheaper and quicker

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Pós-graduação em Engenharia de Produção - FEG

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Pós-graduação em Engenharia Elétrica - FEIS

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Real Options Analysis (ROA) has become a complimentary tool for engineering economics. It has become popular due to the limitations of conventional engineering valuation methods; specifically, the assumptions of uncertainty. Industry is seeking to quantify the value of engineering investments with uncertainty. One problem with conventional tools are that they may assume that cash flows are certain, therefore minimizing the possibility of the uncertainty of future values. Real options analysis provides a solution to this problem, but has been used sparingly by practitioners. This paper seeks to provide a new model, referred to as the Beta Distribution Real Options Pricing Model (BDROP), which addresses these limitations and can be easily used by practitioners. The positive attributes of this new model include unconstrained market assumptions, robust representation of the underlying asset‟s uncertainty, and an uncomplicated methodology. This research demonstrates the use of the model to evaluate the use of automation for inventory control.

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This paper describes a CMOS implementation of a linear voltage regulator (LVR) used to power up implanted physiological signal systems, as it is the case of a wireless blood pressure biosensor. The topology is based on a classical structure of a linear low-dropout regulator. The circuit is powered up from an RF link, thus characterizing a passive radio frequency identification (RFID) tag. The LVR was designed to meet important features such as low power consumption and small silicon area, without the need for any external discrete components. The low power operation represents an essential condition to avoid a high-energy RF link, thus minimizing the transmitted power and therefore minimizing the thermal effects on the patient's tissues. The project was implemented in a 0.35-mu m CMOS process, and the prototypes were tested to validate the overall performance. The LVR output is regulated at 1 V and supplies a maximum load current of 0.5 mA at 37 degrees C. The load regulation is 13 mV/mA, and the line regulation is 39 mV/V. The LVR total power consumption is 1.2 mW.

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Máster Oficial en Gestión Costera

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[ES]Uno de los principales efectos de la subida del nivel del mar es el aumento de la erosión costera. Las Islas Canarias tienen una longitud de costa de 1554 km, de los cuales 10% corresponden a playas de cantos y mixtas. Debido a la inexistencia de trabajos en este tipo de sistemas en el archipiélago canario, el objetivo de esta tesis es realizar un seguimiento de los cantos en la playa de San Felipe, Gran Canaria, mediante la tecnología RFID. Además, se desarrollarán los modelos morfodinámicos de evolución lo que permitirá comprender los patrones de respuesta de las playas de cantos frente al clima marítimo y así tratar de proteger nuestras costas a corto y largo plazo.

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This thesis deals with Context Aware Services, Smart Environments, Context Management and solutions for Devices and Service Interoperability. Multi-vendor devices offer an increasing number of services and end-user applications that base their value on the ability to exploit the information originating from the surrounding environment by means of an increasing number of embedded sensors, e.g. GPS, compass, RFID readers, cameras and so on. However, usually such devices are not able to exchange information because of the lack of a shared data storage and common information exchange methods. A large number of standards and domain specific building blocks are available and are heavily used in today's products. However, the use of these solutions based on ready-to-use modules is not without problems. The integration and cooperation of different kinds of modules can be daunting because of growing complexity and dependency. In this scenarios it might be interesting to have an infrastructure that makes the coexistence of multi-vendor devices easy, while enabling low cost development and smooth access to services. This sort of technologies glue should reduce both software and hardware integration costs by removing the trouble of interoperability. The result should also lead to faster and simplified design, development and, deployment of cross-domain applications. This thesis is mainly focused on SW architectures supporting context aware service providers especially on the following subjects: - user preferences service adaptation - context management - content management - information interoperability - multivendor device interoperability - communication and connectivity interoperability Experimental activities were carried out in several domains including Cultural Heritage, indoor and personal smart spaces – all of which are considered significant test-beds in Context Aware Computing. The work evolved within european and national projects: on the europen side, I carried out my research activity within EPOCH, the FP6 Network of Excellence on “Processing Open Cultural Heritage” and within SOFIA, a project of the ARTEMIS JU on embedded systems. I worked in cooperation with several international establishments, including the University of Kent, VTT (the Technical Reserarch Center of Finland) and Eurotech. On the national side I contributed to a one-to-one research contract between ARCES and Telecom Italia. The first part of the thesis is focused on problem statement and related work and addresses interoperability issues and related architecture components. The second part is focused on specific architectures and frameworks: - MobiComp: a context management framework that I used in cultural heritage applications - CAB: a context, preference and profile based application broker which I designed within EPOCH Network of Excellence - M3: "Semantic Web based" information sharing infrastructure for smart spaces designed by Nokia within the European project SOFIA - NoTa: a service and transport independent connectivity framework - OSGi: the well known Java based service support framework The final section is dedicated to the middleware, the tools and, the SW agents developed during my Doctorate time to support context-aware services in smart environments.

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Il contesto generale nel quale è inserito tale elaborato di tesi è la tecnologia RFID; se ne fa una disamina completa, partendo dalla ricostruzione delle tappe storiche che hanno portato alla sua diffusione. Viene data particolare enfasi alle differenze esistenti tra le varie tipologie, alle frequenze a cui possono operare i dispositivi e agli standard legislativi vigenti. Vengono enunciati inoltre i costi dei dispositivi e le critiche verso la tecnologia. L'obiettivo della tesi è quello di valutare la possibilità di realizzare un meccanismo di monitoraggio a breve raggio di dispositivi dotati di rfid: per questo la visione che si da della tecnologia è il più completa possibile. La prerogativa di lunga durata richiesta dal sistema ha portato a valutare se potesse essere utile integrare un meccanismo di recupero energia; per questo si prosegue con una disamina dell'energy harvesting, fornendo dettagli su tutte le fonti da cui è possibile recuperare energia e casi pratici di meccanismi realizzati, sia che questi siano già presenti sul mercato, sia che siano solo risultati di ricerche e prototipi. Si conclude quindi il lavoro valutando le effettive possibilità di realizzazione del sistema, evidenziando le scelte consigliate per una migliore esecuzione.