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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.
81

Automatisk identifiering med RFID. Utvärdering och möjligheter inom Holmen Paper AB. / Evaluation and possibilities of automatic identification with RFID within Holmen Paper AB

Waldholm, Dennis, Hull, Kristofer January 2005 (has links)
Automatisk produktidentifiering, s.k. Auto-ID, har funnits länge inom många skiljda tillämpningsområden. Det mest välkända systemet idag är streckkodssystemet, vilket blanda annat används i den studerade försörjningskedjan hos Holmen Paper AB. Anledningen till detta examensarbete har varit att undersöka förutsättningarna och möjligheterna till identifiering och spårbarhet med hjälp av RFID, en teknologi som utnyttjar radiofrekvenser för att läsa av produkternas identitet. På det sättet är förhoppningarna att produktions- och leveransprocesser ska kunna effektiviseras, samt att höja informationstillförlitligheten i systemen. I den första teoridelen presenteras generellt betydelsen av RFID för olika typer av applikationsområden och försörjningskedjor. Här presenteras även begreppen ”supply chain management”, samt viktiga skillnader mellan RFID och streckkoder. Några av de faktorer som motverkar företags villighet att införa RFID är bl.a. kostnader, otydlig standardisering, kompatibilitetsproblem mellan produkter, och okunskap kring teknologin. Dessa är ett urval av de delar som belyses i teoriavsnitten. Ett annat syfte med uppsatsen är att höja kunskapsnivån kring flera aspekter om tekniken: hur den fungerar, vilka tekniska krav som är rimliga att ställa, standardiseringsaspekter med mera. Därför beskrivs RFID-teknologierna ur ett generellt perspektiv i den efterföljande delen av rapporten, där alla typer av system presenteras. Undersökningar och studiebesök genomfördes för att kartlägga vilka motiv och behov som finns av RFID, dels på några av Holmen Papers pappersbruk, och dels på terminaler och hos slutkunder. Därmed fanns det underlag för en analys av potentialen med tekniken och förutsättningarna inom tillämpningsområdet. I samband med detta genomfördes marknadsundersökning, bl.a. via intervjuer och kontakt med leverantörer, samt litteraturstudier för att i möjligaste mån kunna svara på om det fanns någon lämplig RFID-lösning värd att investera i. Inriktningen har varit att hitta passiva system, som erbjuder tillräckligt goda avläsningsavstånd under gällande förutsättningar, eftersom dessa betyder låg märkningskostnad jämfört med andra RFID-lösningar. Applikationer inom pappersbranschen är dock ovanliga, vilket har resulterat i att teknikens prestanda behövde verifieras genom tester. Testerna gjordes med framförallt passiva system, vilka i de flesta fall har sämre räckvidd än aktiva och dyrare system. Resultaten visar att någon tillräckligt bra lösning i den studerade applikationen inte kunnat konstateras, d.v.s. uppnådd räckvidd var inte tillräckligt god för tillämpningen hos Holmen Paper. Däremot har uppskattningar gjorts som visar på vilka fysikaliska egenskaper som innebär stora svårigheter för den trådlösa kommunikationen under de givna förutsättningarna.
82

Logistik im Bauwesen

Schach, Rainer, Schubert, Nadine 18 February 2010 (has links) (PDF)
Moderne Logistikkonzepte werden auf vielen Baustellen erfolgreich umgesetzt und gewinnen im Bauwesen – wie in anderen Industriezweigen – zunehmend an Bedeutung. Professionelle Logistik bei der Ver- und Entsorgung sowie auf der Baustelle selbst schafft die Voraussetzung für einen reibungslosen Ablauf bei der Leistungserstellung und trägt somit maßgeblich zur Optimierung von Personal-, Material- und Informationsflüssen und damit zur Kostensenkung bei. Weiteres Potenzial zur Verbesserung der Prozesse auf der Baustelle bieten neue Technologien, so zum Beispiel die RFID-Technologie, die darüber hinaus auch eine dauerhafte und lückenlose Dokumentation im Lebenszyklus des Bauwerks ermöglicht. / Modern logistics concepts are being implemented successfully on many construction sites, and are gaining in importance for the construction industry as a whole. Professional logistics solutions for supplies and waste disposal, as well as for movements on the building site itself, establish the prerequisites for unhindered performance. They contribute significantly to improving the flows of human resources, materials and information, and thus help to lower costs. New technologies such as RFID, which permits long-term and complete documentation over the whole building life cycle, offer further potential to improve construction processes.
83

Modulated Backscatter for Low-Power High-Bandwidth Communication

Thomas, Stewart Jennings January 2013 (has links)
<p>This thesis re-examines the physical layer of a communication link in order to increase the energy efficiency of a remote device or sensor. Backscatter modulation allows a remote device to wirelessly telemeter information without operating a traditional transceiver. Instead, a backscatter device leverages a carrier transmitted by an access point or base station.</p><p>A low-power multi-state vector backscatter modulation technique is presented where quadrature amplitude modulation (QAM) signalling is generated without running a traditional transceiver. Backscatter QAM allows for significant power savings compared to traditional wireless communication schemes. For example, a device presented in this thesis that implements 16-QAM backscatter modulation is capable of streaming data at 96 Mbps with a radio communication efficiency of 15.5 pJ/bit. This is over 100x lower energy per bit than WiFi (IEEE 802.11).</p><p>This work could lead to a new class of high-bandwidth sensors or implantables with power consumption far lower than traditional radios.</p> / Dissertation
84

RFID žymų apsaugos nuo klastojimo metodo sudarymas ir tyrimas / Development and research of RFID tags anti-counterfeiting method

Čereška, Nerijus 21 August 2013 (has links)
Šiame darbe yra sprendžiama RFID žymų apsaugos nuo klastojimo problema, t.y. kaip neleisti žymų klastotojui išgauti originalios žymos ar visos RFID sistemos identifikacinius ir kitus svarbius duomenis, kurių atskleidimas leistų sukurti originalios RFID žymos klastotę. Darbo analizės dalyje yra plačiau apžvelgiama RFID žymų apsaugos nuo klastojimo problema, gilinamąsi į bendrus RFID technologijos veikimo principus ir RFID žymų kategorijas. Taip pat nustatinėjami galimi RFID žymų klastojimo būdai, jų išvengimo galimybės, apžvelgiami ir detalizuojami kitų autorių sukurti apsaugos metodai, pateikiamos rekomendacijos naujam RFID žymų apsaugos nuo klastojimo metodo sudarymui. Tolimesnėje darbo eigoje yra sudarytas naujas RFID žymų apsaugos nuo klastojimo metodas pagal analizės dalyje padarytas rekomendacijas ir suformuluotas išvadas. Pateikiama pradinė metodo saugumo analizė. Pagal sudaryto RFID žymų apsaugos nuo klastojimo metodo koncepciją ir detalų aprašą yra sukurtas programinis modelis, kuris imituoja metodo veikimą realioje aplinkoje. Naudojantis sukurtu programiniu modeliu ir jo generuojamais rezultatais, buvo atliekamas metodo atsparumo klastojimui įvertinimas. Darbo rezultatų dalyje yra analizuojami RFID žymų apsaugos nuo klastojimo metodo sudarymo metu gauti rezultatai, pateikiamos viso darbo išvados, įvertinamas darbo įvade iškeltų tikslų ir užduočių išpildymas. / This paper is addressed to RFID tags anti-counterfeiting problem: how to prevent significant counterfeiters get all important information from orginal tags or all RFID system. The disclosure of that information would provide a chance to create a genuine RFID tag means. A work analysis is a part of a wider survey of RFID tags against counterfeiting problem, explores the general principles of operation of RFID technology and RFID tag categories. It is also explores possible RFID tags manipulation techniques, the avoidance opportunities, an overview and details of other authors to create protection methods and recommendations for a new RFID tags anti-counterfeiting method. The next workflow is composed of new RFID tags anti-counterfeiting method according to the analysis of the recommendations made and the conclusions drawn, provide an initial approach to security analysis. The software model is created by concluded RFID tag anti-counterfeiting method and a detailed description of the concept. The model simulates the performance of the method in a real environment. The ratings of resistance to RFID tags counterfeiting were set using this software model and its generated results. The final part is dedicated to method‘s performance analysis, obtained results and conclusions. It also has objectives and tasks seen in the introduction to the work evaluation.
85

Modellierung, Analyse und Optimierung der Übertragungsstrecke induktiv gekoppelter Transpondersysteme

Deicke, Frank January 2009 (has links)
Zugl.: Dresden, Techn. Univ., Diss., 2009
86

Desenvolvimento de uma antena com diagrama de radiação ajustável para a faixa de frequência UHF de sistemas RFID destinada a sistemas produtivos

Rosa, Flavio Lucas da January 2016 (has links)
Esta dissertação apresenta um estudo que teve por finalidade desenvolver uma solução alternativa para reduzir a intermodulação entre antenas de leitores utilizados em sistemas RFID (Radio Frequency Identification), por esta razão, foi realizada uma pesquisa que consistiu em uma revisão sistemática sobre interferência entre antenas de leitores RFID. Os resultados mostraram que 70% das publicações analisadas foram realizadas em apenas cinco países e que 49% foram publicadas nos últimos três anos. A revisão sistemática também identificou que existem modelos que classificam as técnicas utilizadas para redução da interferenciaentre leitores, porém nenhuma das pesquisas analisadas apresentou uma sintese de classificação que contemplasse todas a técnicas de intermodulação citadas nas pesquisas, o que resultou no desenvolvimento de uma sintese de classificação de intermodulação oriunda de sistemas RFID A revisão identificou que 27% das formas de redução de intermodulação entre antenas manipulava a potência de saída do leitor para redução da área afetada pelas antenas como forma de evitar a intermodulação, porém nenhuma pesquisa propôs realizar alguma modificação nas características das antenas de forma a evitar a interferência ocorrida entre leitores. Esse fato motivou o desenvolvimento de uma antena para a faixa de frequência UHF (Ultra High Frequency) destinada a sistemas RFID com diagrama de radiação ajustável em ambientes de produção. A pesquisa foi desenvolvida com base nos princípios metodológicos de um Modelo para P&D (Pesquisa e Desenvolvimento) para produtos eletrônicos por pequenas equipes, engenheiros independentes e inventores. Como resultado foi obtido um protótipo que foi comparado com antenas comerciais para demonstrar a possibilidade de alterar o lóbulo de radiação. A nova antena desenvolvida também possui um diferencial, que reside na opção de ser utilizada tanto como antena direcional quanto omnidirecional, bastando apenas modificar a configuração de instalação. / This dissertation presents a study that aimed to develop an alternative solution for reducing intermodulation between readers antennas used in RFID systems (Radio Frequency Identification), for this reason, a survey that consisted of a systematic review of interference was carried out between antennas RFID readers. The results showed that 70% of the analyzed publications were performed in only five countries and that 49% have been published in the last three years. The systematic review also found that there are models that classify the techniques used to reduce interferenciaentre readers, but none of the studies analyzed showed a synthesis of classification system encompassing all the intermodulation techniques cited in the research, which resulted in the development of a classification synthesis intermodulation coming from RFID systems. A review showed that 27% of forms of intermodulation reduction between antenna manipulating the reader's output power to reduce the area affected by the antennas in order to avoid intermodulation, but no research proposed to carry some modification in the characteristics of antennas in order to avoid interference occurred between readers. This fact motivated the development of an antenna for the UHF band (ultra high frequency) RFID systems designed with adjustable radiation pattern in production environments. The research was developed based on methodological principles of a model for R & D (Research and Development) for electronic products in small teams, independent engineers and inventors. The result was a prototype which was compared with commercial antennas to demonstrate the ability to change the radiation lobe. The new antenna developed also has a differential, which lies in the option to be used both as directional as omnidirectional antenna by simply modifying the installation configuration.
87

Contribution au développement de la technologie RFID sans puce à haute capacité de codage / Contribution to the development of chipless RFID technology having a large coding capacity

Vena, Arnaud 28 June 2012 (has links)
Malgré les nombreux avantages que procure la RFID, son déploiement demeure freiné par plusieurs facteurs aussi bien économiques, que technologiques. Parmi ces freins, on peut citer le coût encore trop élevé des tags, le manque de fiabilité et de sécurité dans les informations contenues dans la puce RFID mais aussi les aspects «recyclage» des tags. Dans cette thèse nous nous focalisons sur le développement de tags RFID sans puce, qui représentent une nouvelle famille de tags bas coût. Avec cette technologie, l'information est extraite à partir de la réponse électromagnétique du tag qui dépend uniquement de sa géométrie. Différentes solutions ont été développées dans le but d'augmenter la quantité d'informations, de réduire la surface du tag ou encore d'améliorer la robustesse de détection. Des considérations pratiques tel que l'aspect réalisation sur substrat papier, le développement d'un système de détection bas coût, ou encore l'aspect mesure dans un environnement réel on été adressés afin d'établir une preuve de concept. Des travaux sur la réalisation de capteurs RFID sans puce et sur le moyen de rendre un tag sans puce reconfigurable sont présentés en guise de perspective. / Despite the many benefits of RFID, deployment is still hindered by several factors both economic and technological. Among these barriers include the cost of tags still too high, lack of reliability and security in the information contained in the RFID chip but also aspects "recycling" of tags. In this thesis we focus on the development of chipless RFID tag, which represent a new family of low cost tags. With this technology, information is extracted from the electromagnetic response of the tag which depends only on its geometry. Various solutions have been developed to increase the amount of information, reduce the surface of the tag or to improve the robustness of detection. Practical considerations such as realization using paper substrate, the development of a low cost detection system, or measurements in a real environment have been addressed in order to establish proof of concept. The last works concerning chipless RFID sensor or about the way to make a chipless tag fully reconfigurable are presented as a perspective.
88

Desenvolvimento de uma antena com diagrama de radiação ajustável para a faixa de frequência UHF de sistemas RFID destinada a sistemas produtivos

Rosa, Flavio Lucas da January 2016 (has links)
Esta dissertação apresenta um estudo que teve por finalidade desenvolver uma solução alternativa para reduzir a intermodulação entre antenas de leitores utilizados em sistemas RFID (Radio Frequency Identification), por esta razão, foi realizada uma pesquisa que consistiu em uma revisão sistemática sobre interferência entre antenas de leitores RFID. Os resultados mostraram que 70% das publicações analisadas foram realizadas em apenas cinco países e que 49% foram publicadas nos últimos três anos. A revisão sistemática também identificou que existem modelos que classificam as técnicas utilizadas para redução da interferenciaentre leitores, porém nenhuma das pesquisas analisadas apresentou uma sintese de classificação que contemplasse todas a técnicas de intermodulação citadas nas pesquisas, o que resultou no desenvolvimento de uma sintese de classificação de intermodulação oriunda de sistemas RFID A revisão identificou que 27% das formas de redução de intermodulação entre antenas manipulava a potência de saída do leitor para redução da área afetada pelas antenas como forma de evitar a intermodulação, porém nenhuma pesquisa propôs realizar alguma modificação nas características das antenas de forma a evitar a interferência ocorrida entre leitores. Esse fato motivou o desenvolvimento de uma antena para a faixa de frequência UHF (Ultra High Frequency) destinada a sistemas RFID com diagrama de radiação ajustável em ambientes de produção. A pesquisa foi desenvolvida com base nos princípios metodológicos de um Modelo para P&D (Pesquisa e Desenvolvimento) para produtos eletrônicos por pequenas equipes, engenheiros independentes e inventores. Como resultado foi obtido um protótipo que foi comparado com antenas comerciais para demonstrar a possibilidade de alterar o lóbulo de radiação. A nova antena desenvolvida também possui um diferencial, que reside na opção de ser utilizada tanto como antena direcional quanto omnidirecional, bastando apenas modificar a configuração de instalação. / This dissertation presents a study that aimed to develop an alternative solution for reducing intermodulation between readers antennas used in RFID systems (Radio Frequency Identification), for this reason, a survey that consisted of a systematic review of interference was carried out between antennas RFID readers. The results showed that 70% of the analyzed publications were performed in only five countries and that 49% have been published in the last three years. The systematic review also found that there are models that classify the techniques used to reduce interferenciaentre readers, but none of the studies analyzed showed a synthesis of classification system encompassing all the intermodulation techniques cited in the research, which resulted in the development of a classification synthesis intermodulation coming from RFID systems. A review showed that 27% of forms of intermodulation reduction between antenna manipulating the reader's output power to reduce the area affected by the antennas in order to avoid intermodulation, but no research proposed to carry some modification in the characteristics of antennas in order to avoid interference occurred between readers. This fact motivated the development of an antenna for the UHF band (ultra high frequency) RFID systems designed with adjustable radiation pattern in production environments. The research was developed based on methodological principles of a model for R & D (Research and Development) for electronic products in small teams, independent engineers and inventors. The result was a prototype which was compared with commercial antennas to demonstrate the ability to change the radiation lobe. The new antenna developed also has a differential, which lies in the option to be used both as directional as omnidirectional antenna by simply modifying the installation configuration.
89

Le droit et l'intelligence ambiante / The Law face to pervasive intelligence

Aubert, Stéphane 07 December 2010 (has links)
La RFId provoque une évolution dans les moyens d'identification. Exprimant dans un premier temps une logique issue du code à barres, sa mise en œuvre a eu pour finalité d'améliorer la traçabilité pour des raisons essentiellement sanitaires et logistiques. Cependant ce mode d'identification concerne, chaque jour davantage, les personnes physiques. Techniquement c'est au moyen de systèmes RFId que sont mis en œuvre les nouveaux passeports biométriques et cartes nationales d'identité électroniques. C'est également au moyen de ces systèmes que fonctionnent les titres de transport, ou encore les badges des salariés. L'identification est ainsi accrue dans sa précision, mais également dans sa réalisation dans l'espace, et dans le temps. La loi informatique et libertés permet aux personnes physiques de bénéficier d'une protection de leurs données personnelles. Dans le respect de cette loi, les responsables de traitements RFId, identifiant une personne physique, seront tenus de respecter un certain nombre d'obligations. Le recours au consentement des traitements, comme critère de légitimité, modifie l'équilibre du droit des données personnelles. Afin de garantir la protection la plus satisfaisante, de nouveaux moyens sont envisagés. Ceux-ci cherchent à intégrer des procédés techniques, ou encore à offrir à la personne le soin d'assurer elle-même la garantie de ses droits individuels. Le droit fait face, une nouvelle fois, à un défi issu des technologies de l'information et de la communication, dans le respect de ses attributions, et doit permettre qu'un équilibre soit maintenu entre les contraintes économiques et les droits individuels. / RFId implies an evolution of identification technicity. Although, at the beginning, issue of the logic which gave birth to the bar code, this finally developed into a system improving tracability in spheres such as sanitation and logistics. However, more and more each day, this method of identification affects individual, physical, people.It is through this technical progress,that RFId systems produced the new biometric passports and electronic national identity cards. This is also the case for transport vouchers and identity badges for staff, which function using the same systems.Identification precision is thus increased, as also the realisation of identity control at distance .The « informatique et libertés » law is purposed to guarantee people the protection of their private personal details.In order to conform to this law, people responsable for dealing with RFId, which identifies an individual, are constrained to respect a certain nu mber of obligations. Citing previous consent as a criteria of legitimacy, modifies the equilibrium of the law governing personal data .In order to guarantee a more satisfactory protection, new means are envisaged, including integration of technical procedures,or, perhaps, offering to the individual the possibility of guaranteeing his own rights. Once again, the Law has to face up to a new challenge, outcoming from information and communicatio techniques, whilst respecting the limits of its own attributions, and must maintain the equilibrium between economic constraints and individual liberties.
90

Monitoração de rede de sensores com transponders. / Sensors network monitoring with transponders.

Aislan Gomide Foina 16 February 2007 (has links)
Este trabalho apresenta os resultados obtidos no desenvolvimento de um sistema capaz de estabelecer um controle adequado do fluxo da informação e a supervisão de uma rede de sensores. O sistema se caracteriza pelo alto grau de flexibilidade possuindo uma camada de comunicação de dispositivos, uma camada de gerenciamento de regras de negócio para controlar o fluxo de processos, uma camada de interface homem - máquina e de interface com outros sistemas. A camada de comunicação com os dispositivos é responsável pela interface entre os mesmos e o núcleo do sistema, integrando, de forma transparente, diferentes equipamentos, tecnologias e fabricantes. A interface do usuário foi projetada em um único módulo para facilitar modificações sem comprometer o funcionamento geral do sistema. A interface com outros sistemas é feita por meio de drivers de comunicação, permitindo qualquer tipo de integração. O núcleo do sistema faz todo o controle de eventos, do fluxo do processo e geração alarmes, assim como recebimento e envio das informações da camada de dispositivos e da camada de interface. São descritas as diversas camadas da interface e sua implementação analisando as possíveis aplicações do sistema, juntamente com um estudo de caso do controle do processo de descarga de carga a granel no porto de Santos, usando tecnologia RFID. Os resultados obtidos nessa aplicação são descritos e comprovam a utilidade prática do sistema. Apresentam-se inicialmente alguns conceitos básicos necessários ao entendimento deste projeto como: sistemas distribuídos, estrutura webservice, linguagem XML e de tecnologias passíveis de integração com o sistema. / This paperwork presents the results obtained with the development of a system capable of establishing a proper control of information flow and supervision of a sensors network. The system characterizes itself due to its great flexibility degree by having a devices communication layer, a business management layer to do the process flow control, a man-machine interface and interface with other systems layer. The devices communication layer is responsible for the interface between other devices and the system core, integrating in a transparent way, different equipment, technologies and manufactures. The user\'s interface was designed in a single module to facilitate modifications without compromising the system\'s general functioning. The interface with other systems is made throughout communication drivers, allowing any type of integration. The system core makes a control of all events, process flow and alarm generation, as well as receiving and sending information from the devices layer and interface layer. The several interface layers and its implementation are described analyzing the system\'s possible applications along with a case study of loading discharge in a bulk process control at Santos Port using RFID technology. The results obtained with this application are described and prove the practical utility of the system. Some necessary basic concepts to understand this project are presented initially as: distributed systems, web service structure, XML language and technologies subjected to integration with the system.

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