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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.
71

A multi-agent based system RFID middleware for data and device management

Massawe, Libe V., Aghdasi, Farhad, Kinyua, Johnson January 2008 (has links)
Published Article / Radio-frequency Identification (RFID) technology promises to revolutionize business processes. While RFID technology is improving rapidly, a reliable deployment of this technology is still a significant challenge impeding its widespread adoption. In this paper we provide a brief overview of some common fundamental characteristics of RFID data and devices, which pose significant challenges in the design of RFID middleware systems. In addition, the development of a multi-agent RFID middleware solution to address the RFID data and device management challenges is discussed.
72

Design and Implementation of an Augmented RFID System

Borisenko, Alexey 20 June 2012 (has links)
Ultra high frequency (UHF) radio frequency identification (RFID) systems suffer from issues that limit their widespread deployment and limit the number of applications where they can be used. These limitations are: lack of a well defined read zone, interference, and environment sensitivity. To overcome these limitations a novel receiver device is introduced into the system. The use of such device or devices mitigates the issues by enabling more "anchor points" in the system. Two such devices exist in industry and academia: the Astraion Sensatag and the Gen2 Listener. The drawbacks of the Sensatag is that it offers poor performance in capturing tag signals. The Gen2 Listener is based on the expensive software defined radio hardware. The purpose of the thesis was to develop a receiver that will enable several new RFID applications that are not available with current RFID systems. The receiver, named ARR (Augmented RFID Receiver), receives tag and reader signals, which are decoded by an FPGA and the results are reported through Ethernet. This device is central to the augmented RFID system. To show the suitability of such an approach, the performance of the implementation was compared to the other two outlined solutions. A comparison of the read rate and range of the implementations were the defining factors. The analysis showed that the ARR is capable of receiving tag signals with a read rate of 50% for passive and 66% for semi-passive tags at a one meter distance and is capable of receiving tag signals at a maximum of 3.25 meters for passive and 5.5 meters for semi- passive tags, with the reader being within 8 meters of the ARR. Two applications were implemented to showcase the ARR: an RFID portal and protocol analyzer.
73

Pilotage holonique et ambiant, via des technologies infotroniques / Holonic and ambient control, using infotronic technologies

Dubromelle, Yves 16 December 2013 (has links)
Les travaux présentés dans le cadre de cette thèse visent à explorer de nouvelles pistes d’amélioration de la flexibilité, de la sécurité et de la performance des systèmes de production en introduisant les technologies infotroniques dans leur système de pilotage. Cela s’inscrit dans la continuité des travaux sur le modèle PROSIS (Product, Resource, Order and Simulation Isoarchic System). La première piste concerne l’usage de la technologie RFID pour assurer l’intégrité du système d’information et de décision vis-à-vis de l’état matériel du système de production. Pour cela, un tag RFID est associé à la partie matérielle de chaque holon (M_holon), et permet d’assurer la synchronisation avec la partie informationnelle et décisionnelle associée (I_holon). La seconde piste gravite autour du concept d’intelligence ambiante. Les différents traitements de l’information à effectuer par les différents I_holons leurs sont proposés sous la forme de services disponibles en libre accès, en fonction de leurs besoins, par des unités informatiques de soutien. La dernière piste est relative à l’interconnexion entre les activités de production proprement dites et les fonctions support de transitique. Un système de transitique Montrac comprenant des navettes autonomes a été intégré au Holonic Manufacturing Execution System développé dans l’équipe, en utilisant les principes de PROSIS. Les démonstrateurs de ces 3 facettes d’un tel système de pilotage ont été implémentés et validés dans le cadre d'une plateforme de production. Cela a également permis de valider la performance de l’approche vis-à-vis de différents benchmarks issus de la littérature. / The work done during this thesis aims to explore new ways to improve the manufacturing systems flexibility, safety and performances, introducing infotronic technologies into their control systems. This follows some previous work on the PROSIS (Product, Resource, Order and Simulation Isoarchic System) control model. The first way is about the use of RFID technology to ensure the integrity of the information and decision system, regarding the physical state of the manufacturing system. For that, a RFID tag is associated with the material part of each holon (M_holon), and this ensures the synchronisation wi the informational and decisional part (I_holon). The second way is the use of the ambiant intelligence concept. The I_holon has various information processing tasks to do during his lifetime. The tools to do these tasks are proposed to them in the form of services, freely available, and hosted by specialised support entities. The third way of improvement is related to the interconnexion of the actual product processing activities and the internal logistics functions. A Montrac transitic system, including autonomous shuttles, has been integrated in the Holonic Manufacturing Execution System developped during this thesis using the PROSIS principles. These ways of improvement has been implemented in demonstrators to validate their viability in a real small-size workshop. This has allows the comparison of the PROSIS approach with others, using the results of academic benchmarks.
74

Conception d'antennes pour biocapteurs implantables / Antenna designs for implantable biosensors

Perrissol, Philippe 08 December 2015 (has links)
De tous temps, l'amélioration des moyens de guérison et de prévention des maladies a constitué un enjeu majeur de nos sociétés. Les possibilités offertes désormais par les technologies modernes ont permis de multiplier le nombre d'applications médicales mais toutes ces pratiques nouvelles ont un impact dans le domaine de l'expérimentation animale et impliquent aussi un suivi sanitaire à grande échelle. Le travail présenté dans cette thèse a pour but de moderniser la surveillance de l'état de santé des souris de laboratoire, et s'inscrit dans un projet collaboratif entre le LEAT et TIRO-MATOs. L’objectif est la conception d’un système capable de faciliter ce suivi au quotidien. Pour cela, la conception d'une antenne à 433MHz, connectée à un capteur de température, implantable dans une souris et intégrant notamment l'impact de l'environnement biologique a tout d’abord été étudiée. Après caractérisation des éléments obtenus, la faisabilité d’un système de géolocalisation est présentée. Afin de disposer également de la capacité d’identification des sujets, cette étude s’est poursuivie à 868 MHz (standard RFID). Dans cette partie, l’antenne interrogatrice placée sous la cage, a été plus particulièrement étudiée. Afin de comparer les différentes antennes obtenues, des mesures de puissance récupérées par le lecteur (RSSI) sont réalisées, utilisant pour cela des phantoms de souris spécialement mis au point pour cette étude. Les conclusions tirées par comparaison notamment avec les résultats de phantoms numériques ont permis de concevoir un dispositif de diversité à 4 antennes et de le tester en présence de un à quatre phantoms dans quatre différentes zone de la cage. / The improvement of the methods of cure and prevention of diseases has always constituted a major objective in our societies. The possibilities offered by modern technologies allow the multiplication of the number of medical applications but all these new practices have an impact on pre-clinical animal studies which require a large-scale health status follow-up. This work, which aims at modernizing the supervision of laboratory mice in an animal facility, is a collaborative project between the LEAT and TIRO-MATOs labs. The objective is the design of a system allowing to facilitate this follow-up for the researchers while leading to new research areas. Thus, we first studied the conception of an antenna working at 433MHz, connected to a mouse implanted temperature sensor, taking also into account the biological environment impact. After having characterized the obtained elements, the feasibility of a localization system has been studied. In order to identify several mice within a cage, the study has focused on using an UHF RFID (Radio Identification Frequency) standard (868 MHz). In this part, a reader antenna placed under the cage has been investigated. Different solutions have been proposed and compared thanks to the received power (RSSI level) recorded by the reader. For that purpose, mice “phantoms” have been specifically developed. The comparison of the different results obtained particularly with numerical mice “phantoms”, led to the conception of a reading diversity system composed of 4 antennas. This last system allows to detect the presence of up to four phantoms within a cage divided into four zones.
75

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

Foina, Aislan Gomide 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.
76

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.
77

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)
<p>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.</p><p>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. </p><p>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.</p>
78

Design and Implementation of an Augmented RFID System

Borisenko, Alexey 20 June 2012 (has links)
Ultra high frequency (UHF) radio frequency identification (RFID) systems suffer from issues that limit their widespread deployment and limit the number of applications where they can be used. These limitations are: lack of a well defined read zone, interference, and environment sensitivity. To overcome these limitations a novel receiver device is introduced into the system. The use of such device or devices mitigates the issues by enabling more "anchor points" in the system. Two such devices exist in industry and academia: the Astraion Sensatag and the Gen2 Listener. The drawbacks of the Sensatag is that it offers poor performance in capturing tag signals. The Gen2 Listener is based on the expensive software defined radio hardware. The purpose of the thesis was to develop a receiver that will enable several new RFID applications that are not available with current RFID systems. The receiver, named ARR (Augmented RFID Receiver), receives tag and reader signals, which are decoded by an FPGA and the results are reported through Ethernet. This device is central to the augmented RFID system. To show the suitability of such an approach, the performance of the implementation was compared to the other two outlined solutions. A comparison of the read rate and range of the implementations were the defining factors. The analysis showed that the ARR is capable of receiving tag signals with a read rate of 50% for passive and 66% for semi-passive tags at a one meter distance and is capable of receiving tag signals at a maximum of 3.25 meters for passive and 5.5 meters for semi- passive tags, with the reader being within 8 meters of the ARR. Two applications were implemented to showcase the ARR: an RFID portal and protocol analyzer.
79

Kontinuerlig RFID-detektering för batteridrivna system

Justegård, Henrik, Ljungblom, Fredrik January 2013 (has links)
This report deals with RFID systems and how to detect nearby tags with the Mifare standard using only a microcontroller and an antenna circuit. The aim was to investigate whether there was any possibility to continuously search for a nearby tag for a system operated with batteries without compromising   the lifespan of the battery. At this time the system would take too long time to wake up and look for a tag to give a satisfactory battery lifespan, which should be done a couple of times every second. The report has two issues, namely: Is it possible to direct the microprocessor to detect and identify a nearby tag after the Mifare standard? What hardware is required for this to be possible? As the research method to provide answers to the above questions an action research was used. This approach has meant that the group worked on information retrieval, examined existing solutions, tested their own solutions and documented the results. The group examined an existing solution that can search for nearby tags with minimal energy consumption. An antenna circuit was built that was connected to the processor. The program code was made in AVR Studio on a PC and programmed with a AVR one!. The processor was in an AVR Xplain development board for processors made by Atmel. The software is designed to wake up the system to search for a tag as quickly as possible, and then go back to sleep. By only activating the carrier and measure the amplitude of the received signal could determine whether a tag is around or not. This made it possible to conduct a search for a tag of less than 4 µS.
80

Marknadsundersökning för en fuktsensor med RFID-teknik

Edmon, Nivin, Andersson, Antonia January 2011 (has links)
Fukt i byggnader är svårt att upptäcka och är ett vanligt problem i dag.Att i ett tidigt skede kunna se hur fuktigt det är kan bespara dyrakostnader. En ny produkt som företaget Sensible Solutions har tagitfram är en fuktsensor som kan placeras innanför väggar i till exempelbadrum. Fuktsensorn består av två RFID-taggar där en av taggarna äromsluten i ett fuktabsorberande material. När det fuktabsorberandematerialet drar åt sig fukt kommer den taggen bli svårare att läsa av,vilket indikerar att fukt förekommer. Avläsningen av fuktsensorn skergenom en handhållen RFID-läsare. En marknadsundersökning hargenomförts med hjälp av en litteraturstudie av skriftliga och webbaseradekällor samt intervjuer med potentiella kunder och en befintligkund. Undersökningen fokuserar på byggföretag i Sverige för att ta redapå vilken marknad Sensible Solutions fuktsensor passar in samt vemslutkund är. Marknadsundersökningen innefattar potentiell marknad,en konkurrentanalys, en SWOT-analys samt en kundundersökning.Granskningen har visat att ett intresse för RFID-teknik samt fuktsensornfinns, men ytterligare information är efterfrågad. Produkterna tillrespektive konkurrent har sina för- och nackdelar men Sensible Solutionsprodukt anses vara unik. En möjlighet som SWOT-analysen visarär bland annat att en vidareutveckling av den befintliga produkten samtav nya produkter finns. Sensible Solutions befintliga kund använder idag fuktsensorn i ett pilotprojekt och pekade på fördelen med fuktsensornatt fuktigheten kunde mätas både under och efter byggtid. Enslutsats är att byggföretag är en rimlig marknad för Sensible Solutionsatt inrikta sig på då den tekniska kompetensen finns och likaså intressetför RFID-teknik och fuktsensorer. / Humidity in buildings is a problem that is difficult to detect and is thusa common problem in present day construction. The ability to detecthumidity at an early stage can be of assistance in the prevention ofexpensive costs. A new product developed by the Sensible Solutionscompany is a humidity sensor that can be placed inside walls, in, forexample, bathrooms. The humidity sensor consists of two RFID tags,one of which is enclosed in a moisture-absorbing material and whenmoisture is absorbed the enclosed tag becomes more difficult to read,which indicates that the humidity is higher than an expected value. Thehumidity sensor is read using an RFID handheld mobile computer.Market research has been conducted by collecting of data from writtensources and the Internet and by conducting interviews with existing andpotential customers; the target group for the research is constructioncompanies. The goal for this market research is to find a prospectivemarket for the Sensible Solutions humidity sensor based on theexpectations of the users. The market research dealt with the potentialmarket, a competitor analysis, a SWOT analysis and a customer survey.The audit revealed that an interest in RFID technology and the humiditysensor did exist, but that more information was required. Each of thecompetitors products have their pros and cons but the SensibleSolutions product is considered to be unique. One possibility shown upby the SWOT analysis is that further development of the existingproducts and new products is possible. The humidity sensor is currentlybeing used by a Sensible Solutions customer in a project, to ensure thequality of the construction during and after implementation. Inconclusion, the construction company market is a reasonable one forSensible Solutions to focus on as these companies possess the technicalcompetence and also the necessary interest in RFID technology andhumidity sensors.

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