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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

Inferring social structure and dominance relationships between rhesus macaques using RFID tracking data

Maddali, Hanuma Teja 22 May 2014 (has links)
This research address the problem of inferring, through Radio-Frequency Identification (RFID) tracking data, the graph structures underlying social interactions in a group of rhesus macaques (a species of monkey). These social interactions are considered as independent affiliative and dominative components and are characterized by a variety of visual and auditory displays and gestures. Social structure in a group is an important indicator of its members’ relative level of access to resources and has interesting implications for an individual’s health. Automatic inference of the social structure in an animal group enables a number of important capabilities, including: 1. A verifiable measure of how the social structure is affected by an intervention such as a change in the environment, or the introduction of another animal, and 2. A potentially significant reduction in person hours normally used for assessing these changes. The behaviors of interest in the context of this research are those definable using the macaques’ spatial (x,y,z) position and motion inside an enclosure. Periods of time spent in close proximity with other group members are considered to be events of passive interaction and are used in the calculation of an Affiliation Matrix. This represents the strength of undirected interaction or tie-strength between individual animals. Dominance is a directed relation that is quantified using a heuristic for the detection of withdrawal and displacement behaviors. The results of an analysis based on these approaches for a group of 6 male monkeys that were tracked over a period of 60 days at the Yerkes Primate Research Center are presented in this Thesis.
252

Design and development of novel radio frequency sensors based on far-field and near-field principles

Thai, Trang Thuy 13 January 2014 (has links)
The objective of this work is to enhance and advance sensing technologies with the design and development of novel radio frequency (RF) sensors based on far-field and near-field principles of the electromagnetic (EM) resonances. In the first part of this thesis, original design and development of a passive RF temperature sensor, a passive RF strain sensor, and a passive RF pressure sensor are presented. The RF temperature sensor is presented in Chapter 3. It is based on split ring resonators loaded with bimorph cantilevers. Its operating principles and equivalent circuits are discussed in Chapter 4, where the design concept is illustrated to be robust and highly adaptable to different sensing ranges, environments, and applicable to other type of sensing beyond temperatures. The passive RF strain sensor, based on a patch antenna loaded with a cantilever-integrated open loop, is presented in Chapter 5, where it is demonstrated to have the highest strain sensitivity in the same remote and passive class of sensors in the state-of-the-art. Chapter 6 describes the passive RF pressure sensor, which is based on a dual-band stacked-patch antenna that allows both identification and sensing to be embedded in its unique dual resonant responses. In the second part of this thesis, an original and first-of-its-kind RF transducer is presented that enables non-touch sensing of human fingers within 3 cm of proximity (based on one unit sensor cell). The RF transducer is based on a slotted microstrip patch coupled to a half-wavelength parallel-coupled microstrip filter operating in the frequency range of 6 – 8 GHz. The sensing mechanism is based on the EM near-field coupling between the resonator and the human finger. Fundamentally different from the electric field capacitive sensing, this new method of sensing, the first of its kind, based on near-field interference that produces a myriad of nonlinearities in the sensing response, can introduce new capabilities for the interface of electronic displays (the detection is based on pattern recognition). What set this sensor and its platform apart from previous proximity sensors and microwave sensing platforms is the low profile planar structure of the system, and its compatibility with mobile applications. The thesis provides both breadth and depth in the proposed design and development and thus presenting a complete research in its contributions to RF sensing.
253

RFID in Virtuellen Unternehmen: Potenziale von Data-on-Tag

Werner, Kerstin, Grummt, Eberhard 23 April 2014 (has links) (PDF)
No description available.
254

MODELISATION ET SIMULATION DE L’INTRODUCTION DE TECHNOLOGIES RFID DANS DES SYSTEMES DE CONFIGURATION A LA DEMANDE / MODELING AND SIMULATION OF THE INTRODUCTION OF RFID TECHNOLOGIES IN CONFIGURATION TO ORDER SYSTEMS

Haouari, Lobna 18 December 2012 (has links)
L'IDentification par Radio-Fréquences (RFID) permet une identification rapide et efficace des objets. Dans les systèmes de personnalisation de masse, elle promet un apport considérable grâce à sa capacité à gérer des flux d'information complexes caractérisant ce type de systèmes.Dans cette thèse, nous étudions les impacts de la RFID sur les systèmes de configuration à la demande (CTO). Nous nous basons sur un cas réel pour apporter une mesure fiable et directement exploitable. La littérature à ce sujet offre souvent des mesures sommaires, théoriques ou qualitatives, d'où l'originalité de la thèse.L'étude est réalisée par une approche de simulation à évènements discrets et évalue l'apport des technologies RFID à deux niveaux. Le premier concerne des changements directs du système (e.g. accélération des maintes vérifications caractérisant la CTO, libération de ressources...). Ces changements influencent la performance du système en termes de temps de séjour, de taux de retard des commandes, etc. Le deuxième niveau concerne des changements profonds tirant profit d'une visibilité accrue des produits et de la facilité d'une collecte de données rigoureuse. Ces changements se focalisent sur l'allocation dynamique de la charge de travail. La remise en question des processus à l'occasion de l'introduction d'une technologie RFID constitue un point original en raison du manque de publications soulignantsuffisamment cet avantage.Nos expérimentations ont montré que les apports des technologies RFID dans un système CTO sont indéniables. De plus, repenser le fonctionnement du système afin d'exploiter plus profondément le potentiel de la technologie accroit les bénéfices. / Radio Frequency IDentification allows quick and secure identification of objects. In mass customisation systems, RFID technologies can be peculiarly efficient, because they are able to support the complex flows of information which characterize these systems.In this study, we focus on RFID technologies effects on configuration to order (CTO) systems.We base the research on an existing case in order to obtain reliable information directly usable by decision makers. The rarity of studies offering quantitative, detailed and real case based measures makes the originality of this thesis.RFID technology implementation's effect is analysed by a discrete event simulation approach and is presented in two levels:The first level relates direct changes brought about by RFID (e.g. faster execution of the many checks due to the wide range of products, reduced workload for resources…). These changes have an impact on system's performance in terms of lead time, late orders' rate, etc.The second level is axed on deeper changes occurring due to the increased product visibility and the ease of collecting large amounts of data with an RFID technology.These changes mainly focus on the dynamic allocation of workload. Reconsidering of processes and proposing changes deeper than the simple direct technology impact is a breakthrough, in this study, because of the lack of publications highlighting this benefit adequately.In conclusion, RFID contribution in CTO systems and, extensively, in assembly to order systems may be undeniable. Moreover, beyond the direct technology impact, rethinking how the system works by exploiting the deeper potential of technology can increase profits.
255

Contribuições para a melhoria da gestão de resíduos de eletroeletrônicos no Brasil, no contexto da sustentabilidade ambiental / Contributions to the improvement of electronic waste management in Brazil, in the context of environmental sustainability

Oliveira, Uanderson Rébula [UNESP] 24 March 2016 (has links)
Submitted by UANDERSON REBULA DE OLIVEIRA null (grc@unesp.br) on 2016-04-19T05:50:16Z No. of bitstreams: 1 Dissertação - Uanderson - versão final.pdf: 15907044 bytes, checksum: 28e3e51a30e15b09c634a073c9b7eb35 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-25T18:24:33Z (GMT) No. of bitstreams: 1 oliveira_ur_me_guara.pdf: 15907044 bytes, checksum: 28e3e51a30e15b09c634a073c9b7eb35 (MD5) / Made available in DSpace on 2016-04-25T18:24:33Z (GMT). No. of bitstreams: 1 oliveira_ur_me_guara.pdf: 15907044 bytes, checksum: 28e3e51a30e15b09c634a073c9b7eb35 (MD5) Previous issue date: 2016-03-24 / A venda de Equipamentos Eletroeletrônicos (EEE) cresce em razão das inovações tecnológicas e da rapidez com que eles se tornam obsoletos, o que implica o aumento da geração de um resíduo sólido denominado Resíduo de Equipamento Eletroeletrônico (REEE). O REEE é um problema relevante, visto que contém diversas substâncias tóxicas capazes de provocar danos ao meio ambiente e à saúde humana. Dessa forma, torna-se necessário um gerenciamento ambientalmente adequado. Após a criação da Política Nacional de Resíduos Sólidos (PNRS) no Brasil, passou a caber a fabricantes, importadores, distribuidores e comerciantes de EEE o dever de implementar sistemas de Logística Reversa (LR), os quais objetivam o retorno dos produtos após o uso pelo consumidor. Apesar de o setor de Eletroeletrônicos se preocupar com a LR de seus produtos, constatou-se, na literatura, que a LR do REEE é um tema ainda pouco explorado, tanto no âmbito nacional quanto no internacional, como evidencia a carência de trabalhos práticos nessa área. Esta pesquisa tem por objetivo identificar como a gestão de REEE pode contribuir para a melhoria do desempenho da cadeia de suprimentos de EEE no Brasil, no contexto da sustentabilidade ambiental. Para tanto, adotou-se um método de pesquisa de natureza aplicada, com abordagem qualitativa, objetivo exploratório e normativo e uso de procedimentos técnicos, tais como levantamento bibliográfico, análise documental e ex-post facto. A Revisão Sistemática da Literatura possibilitou identificar: o histórico, o panorama e as perspectivas, global e brasileira, para a melhoria do desempenho da gestão de REEE no contexto da sustentabilidade ambiental; boas práticas internacionais em gestão de REEE, as quais sugerem melhorias para o desempenho da gestão de REEE no Brasil; e boas práticas de uso das tecnologias de identificação de produtos, tal como a Radio Frequency Identification (RFID), nos sistemas de LR dos REEE, a exemplo do Projeto Smartwaste da Hewlett-Packard (HP). / The sale of electrical and electronic equipment (EEE) grows in terms of technological innovation and the speed with which they become obsolete, reflecting the increase in the generation of a solid residue called electro-electronic equipment waste (WEEE). The WEEE is a major problem, as it has several toxic substances capable of causing damage to the environment and human health. Thus, an environmentally proper management becomes necessary. With the creation of the National Policy on Solid Waste (NPSW) in Brazil, manufacturers, importers, distributors and EEE traders should implement Reverse Logistics systems (RL) by return of products after use by the consumer. Although the electronics industry to worry about the LR of its products, found in the literature that the LR of WEEE is presented as a relatively unexplored subject, both nationally and internationally, showing lack of practical work in this area. The research aims to identify how the management of WEEE can contribute to improving the performance of EEE supply chain in Brazil, in the context of environmental sustainability. Therefore, we adopted a method of nature applied research, with a qualitative approach with exploratory and normative goal, and use of technical procedures, such as literature, document analysis and ex-post facto. A Systematic Review of the Literature possible to identify: the history, the outlook and prospects, global and Brazilian, to the improvement of WEEE management performance in the context of environmental sustainability; best international practices in the management of WEEE, suggesting improvements to the WEEE management performance in Brazil; and good practice in the use of product identification technologies such as Radio Frequency Identification (RFID) in LR systems of WEEE, such as the Smartwaste Hewlett-Packard Project (HP).
256

Internet of Things påverkan på informationsflödet : En fallstudie på Saab Training & Simulation / Internet of Things impact on the information flow : A case study at Saab Training & Simulation

Käll, Nathalie, Fransson, Rebecca January 2018 (has links)
Syfte: Studien ämnar att studera hur Internet of Things skulle kunna integreras för att minska potentiella brister i informationsflödet hos tillverkande företag. För att möjliggöra detta formulerades två forskningsfrågor:  <li data-aria-level="1" data-aria-posinset="1" data-listid="12" data-font="Georgia,Serif" data-leveltext="%1.">Hur är informationsflödet utformat hos ett tillverkande företag med högt anpassade kundprocesser?  <li data-aria-level="1" data-aria-posinset="1" data-listid="12" data-font="Georgia,Serif" data-leveltext="%1.">Vilka möjligheter ger Internet of Things för att minska potentiella brister i informationsflödet?  Metod: En förundersökning gjordes för att ge författarna en bild av studiens problemområde. Vidare genomfördes en litteraturstudie och en fallstudie. Litteraturstudien skapade studiens teoretiska ramverk och innehåller områden som Internet of Things, information, kommunikation, informationsflöde och informationssystem. Fallstudien genomfördes på ett stort tillverkande företag och bestod av dokumentstudier, observationer och en fokusgrupp. En sammankoppling av studiens teoretiska ramverk och empiri genererade studiens resultat.  Resultat: Företagets informationsflöde visade sig vara komplext och innehålla mycket manuell hantering av information. Något som visade sig ge konsekvenser för informationens pålitlighet, relevans och tidsperspektiv. Det finns därför förbättringsmöjligheter genom att integrera Internet of Things, då en digitalisering av informationsflödet skulle kunna leda till standardiserade processer samt en större och säkrare mängd delad information.  Implikationer: Teoretiskt bidrar studien genom att utvärdera hur Internet of Things kan bidra till nya sätt att arbeta med informationsflöden hos tillverkande företag. Studien visar detta genom att analysera viktiga aspekter inom ett nuvarande informationsflöde och Internet of things. Praktiskt bidrar studien med att identifiera potentiella förbättringsmöjligheter i ett företags informationsflöde genom en integration av Internet of Things.  Begränsningar: Studien är designad som en enfallsstudie vilket begränsar generaliserbarheten. Andra företag kan komma att behöva undersöka sina specifika förutsättningar för att dra nytta av studien. Generaliserbarheten ökar till viss del då Internet of Things är ett brett ämne och kan appliceras på ett stort antal områden. För att öka studiens tillförlitlighet har metodkapitlet noggrant utformats och beskrivits. / Purpose: This study aims to explore how Internet of Things could be integrated in manufacturing companies to reduce the potential inadequacy in an information flow. To achieve this, two research questions were formed:  <li data-aria-level="1" data-aria-posinset="1" data-listid="13" data-font="Georgia,Serif" data-leveltext="%1.">How is the information flow designed in a manufacturing company that produces customer-specific products?  <li data-aria-level="1" data-aria-posinset="1" data-listid="13" data-font="Georgia,Serif" data-leveltext="%1.">What possibilities does Internet of Things give information flow to reduce potential inadequac <p data-aria-level="1" data-aria-posinset="2" data-listid="13" data-font="Times New Roman" data-leveltext="%1.">Method: A pilot study was conducted to help the authors create a picture of the study's problem area. Later a literature study and a case study were conducted. The literature study was conducted to create the theoretical framework and included areas such as Internet of Things, information, communication, information flow and information systems. The case study conducted at a large manufacturing company and was consisted document studies, observations and a focus group. The results of the study are generated through a pairing of the theoretical framework and empirical study.  <p data-aria-level="1" data-aria-posinset="2" data-listid="13" data-font="Times New Roman" data-leveltext="%1.">Findings: The company's information flow was complex and contained a lot of manual management of information and communication. This turned out to create consequences for the information’s reliability, relevance, and timing. It has therefore been found that there are improvement opportunities through an integration of IOT in the information flow. A digitalization of an information flow can lead to creation of standard process and a larger and safer amount of shared information.  <p data-aria-level="1" data-aria-posinset="2" data-listid="13" data-font="Times New Roman" data-leveltext="%1.">Implications: The study contributes theoretically by evaluating how IOT can contribute to innovative ways of working with information flows at manufacturing companies; this by analysing key aspects of a current information flow and IOT. Practically, the study contributes to identifying potential improvements by integrate IOT in a corporate information flow.  Limitations: The study is of a one-case-design which limits generalisability. Therefore, other companies may need to examine their specific requirements before taking advantage of the study. The generalization increases slightly due to the broadness of the term IOT and that it can be applied in a wide range of areas. The method chapter has been carefully designed and described to increase the study's reliability.
257

Systemization of RFID Tag Antenna Design Based on Optimization Techniques and Impedance Matching Charts

Butt, Munam January 2012 (has links)
The performance of commercial Radio Frequency Identification (RFID) tags is primarily limited by present techniques used for tag antenna design. Currently, industry techniques rely on identifying the RFID tag application (books, clothing, etc.) and then building antenna prototypes of different configurations in order to satisfy minimum read range requirements. However, these techniques inherently lack an electromagnetic basis and are unable to provide a low cost solution to the tag antenna design process. RFID tag performance characteristics (read-range, chip-antenna impedance matching, surrounding environment) can be very complex, and a thorough understanding of the RFID tag antenna design may be gained through an electromagnetic approach in order to reduce the tag antenna size and the overall cost of the RFID system. The research presented in this thesis addresses RFID tag antenna design process for passive RFID tags. With the growing number of applications (inventory, supply-chain, pharmaceuticals, etc), the proposed RFID antenna design process demonstrates procedures to design tag antennas for such applications. Electrical/geometrical properties of the antennas designed were investigated with the help of computer electromagnetic simulations in order to achieve optimal tag performance criteria such as read range, chip-impedance matching, antenna efficiency, etc. Experimental results were performed on the proposed antenna designs to compliment computer simulations and analytical modelling.
258

Etiqueta de RFID em UHF para objetos metálicos / UHF RFID Tag for metallic objects

Barbin, Manoel Vitorio, 1957- 27 August 2018 (has links)
Orientador: Michel Daoud Yacoub / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-27T01:29:54Z (GMT). No. of bitstreams: 1 Barbin_ManoelVitorio_M.pdf: 5394528 bytes, checksum: f2e1dbef898be5580589baf0e2996f16 (MD5) Previous issue date: 2015 / Resumo: A identificação de objetos através de ondas de radiofrequência ou RFID (Radio Frequency Identification) é uma tecnologia onde uma etiqueta, colocada em um objeto, tem suas informações lidas por um sistema de processamento remoto. Embora esta não seja uma tecnologia recente, sua utilização tem apresentado constante crescimento nos últimos anos. Atualmente, RFID é apontada com uma das principais tecnologias habilitadoras da internet do futuro, a Internet das Coisas, IoT (Internet of Things). Operando principalmente em faixas destinadas para o uso de aplicações médicas, científicas e industriais, ISM (Industrial, Scientific and Medical), sistemas de RFID apresentam diferentes características em função da banda de frequências utilizada. Em UHF (Ultra High Frequency), os sistemas de RFID que fazem uso de etiquetas passivas, são considerados como uma solução com bom desempenho para a identificação de objetos em distâncias que variam de alguns poucos centímetros a vários metros. Contudo, a distância de identificação depende do material que constitui um dado objeto. Por exemplo, metais estão entre os materiais que degradam significativamente o desempenho de sistemas de RFID em UHF, reduzindo a distância de identificação. Diversas soluções de etiquetas têm sido desenvolvidas com o objetivo de torná-las, o máximo possível, insensíveis à presença do metal. Alguns diferentes tipos de antenas foram propostas, entre as quais se destacam as que possuem um plano-terra inerente a sua estrutura, como a de microfita e a planar de F-Invertido, PIFA (Planar Inverted-F Antenna). Uma revisão destas soluções é realizada nesta dissertação. Este trabalho descreve o projeto de uma etiqueta passiva de RFID em UHF, baseado em uma PIFA, para identificação de objetos metálicos colocados em distâncias maiores que oito metros, aproximadamente. O principal objetivo de uso da etiqueta é na identificação de objetos com razoáveis dimensões tais como containers, chapas, canos, etc., frequentemente encontrados em ambientes industriais e armazéns de estocagem. Uma forma diferente de alimentação do sinal de radiofrequência para a antena é desenvolvida. Simulações eletromagnéticas e medições indicam um bom desempenho da etiqueta em uma ampla faixa de frequências, que abrange as principais bandas de operação de RFID em UHF no mundo / Abstract: The identification of objects by radio waves or RFID (Radio Frequency Identification) is a technology where a tag is attached to an object and its information read by a remote processing system. Although it is not a new technology, its use has shown steady growth in recent years. Currently, RFID is identified as one of the main enabling technologies of the future Internet, the Internet of Things, IoT. Operating in the bands intended primarily for use in industrial, scientific and medical (ISM) applications, RFID systems have different characteristics depending on the frequency band used. In the UHF (Ultra High Frequency) band, RFID systems using passive tag are considered as a solution with good performance to identify objects at distances ranging from a few centimeters to several meters. However, the distance of identification depends on the material that the object is made of. For example, metals are materials which can significantly degrade the performance of UHF RFID systems by reducing the distance of identification. Several solutions for tags have been developed in order to make them, as far as possible, insensitive to the presence of metal. Some different types of antennas were proposed, among which are those with a ground plane inherent in its structure, such as the microstrip antenna and the PIFA (Planar Inverted-F Antenna). A review of these solutions is carried out in this dissertation. This document describes the design of a passive RFID tag in UHF, based on a PIFA for identification of metallic objects placed at distances greater than eight meters or so. The main use of the tag is to identify objects with medium or large dimensions such as containers, plates, pipes, etc., often found in industrial environments and storage warehouses. A different kind of RF feeder to the antenna is developed. Electromagnetic simulations and measurements indicate a good tag performance in a wide frequency band, which covers the main RFID UHF operation bands in the world / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
259

RFID in Virtuellen Unternehmen: Potenziale von Data-on-Tag

Werner, Kerstin, Grummt, Eberhard January 2007 (has links)
No description available.
260

System and Method for Passive Radiative RFID Tag Positioning in Realtime for both Elevation and Azimuth Directions

Modaresi, Mahyar January 2010 (has links)
In this thesis, design and realization of a system which enables precise positioning of RFID tags in both azimuth and elevation angles is explained. The positioning is based on measuring the phase difference between four Yagi antennas placed in two arrays. One array is placed in the azimuth plane and the other array is perpendicular to the first array in the elevation plane. The phase difference of the signals received from the antennas in the azimuth array is used to find the position of RFID tag in the horizontal direction. For the position in the vertical direction, the phase difference of the signals received from the antennas in the elevation plane is used. After that the position of tag in horizontal and vertical directions is used to control the mouse cursor in the horizontal and vertical directions on the computer screen. In this way by attaching one RFID tag to a plastic rod, a wireless pen is implemented which enables drawing in the air by using a program like Paint in Windows. Simulated results show that the resolution of the tag positioning in the system is in the order of 3mm in a distance equal to 0.5 meter in front of the array with few number of averaging over the received phase data. Using the system in practice reveals that it is easily possible to write and draw with this RFID pen. In addition it is argued how the system is totally immune to any counterfeit attempt for faked drawings by randomly changing the transmitting antenna in the array. This will make the system a novel option for human identity verification. / QC 20100920

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