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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.
11

Developing and Building a Lean Based RFID Electronic Kanban Prototype

Chang, Ryan 01 September 2012 (has links) (PDF)
The kanban system is a popular Toyota lean manufacturing tool used to help facilitate material movement between workstations and suppliers. Since the 1950’s, the original kanban system has undergone many different variations due to the advancement of technology and unique company implementation. This report focuses on the development and building of a new variation of the kanban system using lean principles while integrating radio frequency identification (RFID) technology with a fully electronic based kanban card system. This new type of kanban system will be called the RFID E-Kanban in this report. Since the lean philosophy is to reduce non-value added waste to a process, the new prototype kanban system meets four design objectives that are consistent with the principles of lean and the original purpose of the kanban system. The RFID E-Kanban prototype must support the process of continuous improvement The RFID E-Kanban prototype must reduce overall non-value added waste to the material flow process The RFID E-Kanban prototype must be intuitive and simple to use for the operator The RFID E-Kanban prototype control must be decentralized In an applied case study, a RFID E-Kanban prototype was built for a Department of Defense facility involving the movement of chemicals between two locations.
12

Comptage et surveillance d'étiquettes dans des systèmes RFID à grande échelle : base théorique et conception d'algorithmes / Tag Counting and Monitoring in Large-scale RFID systems : Theoretical Foundation and Algorithm design

Yu, Jihong 06 December 2016 (has links)
La technologie « Radio Frequency Identification (RFID) » est devenue de plus en plus répandue dans le déploiement de diverses applications, telles que le contrôle des stocks et la gestion de la chaîne d'approvisionnement. Dans cette thèse, nous présentons une recherche systématique sur les problèmes de recherche liés au comptage et à la surveillance d’étiquettes RFID, deux composants fondamentaux dans les systèmes RFID, en particulier dans des systèmes à grande échelle. Ces problèmes sont simples à formuler et intuitivement compréhensible, tandis que tous les deux présentent des défis importants à la fois fondamentaux et pratiques, et exigent des efforts non négligeables à résoudre. Plus précisément, nous abordons les problèmes suivants allant de la modélisation et de l'analyse théorique, à la conception et l’optimisation de l'algorithme pratique. Pour poser les bases théoriques pour la conception et l'optimisation des algorithmes de comptage et la surveillance d'étiquette, nous commençons par étudier la stabilité de FSA. Techniquement, nous modélisons le “backlog’’ du système comme une chaîne de Markov, dont ses états sont la taille du “backlog’’ au début de chaque trame. Nous établissons ensuite un cadre générique d'estimation du nombre d’étiquettes RFID basée sur le filtre de Kalman pour des systèmes RFID statiques et dynamiques. Nous procédons en suite à résoudre le problème de détection des étiquettes manquantes, l'une des applications les plus importantes dans les systèmes RFID. Différent des travaux existants dans ce domaine, nous nous concentrons sur deux scénarios inexplorés mais fondamentalement importants, celui en présence d'étiquettes inattendues et celui des systèmes RFID multiple-région multi-groupe. Dans le premier scénario, nous développons un protocole à deux phases à base de filtre de Bloom. Dans le deuxième scénario, nous développons trois protocoles de détection d'étiquette manquante en intégrant une version améliorée de la conception du filtre Bloom. / Radio Frequency Identification (RFID) technology has been deployed in various applications, such as inventory control and supply chain management. In this thesis, we present a systematic research on a number of research problems related to tag counting and monitoring, one of the most fundamental component in RFID systems, particularly when the system scales. These problems are simple to state and intuitively understandable, while of both fundamental and practical importance, and require non-trivial efforts to solve. Specifically, we address the following problems ranging from theoretical modeling and analysis, to practical algorithm design and optimization. To lay the theoretical foundations for the algorithm design and optimization, we start by studying the stability of frame slotted Aloha. We model system backlog as a Markov chain. The main objective is translated to analyze the ergodicity of the Markov chain. We then establish a framework of stable and accurate tag population estimation schemes based on Kalman filter for both static and dynamic RFID systems. We further proceed to addressing the problem of missing tag detection, one of the most important RFID applications. Different from existing works in this field, we focus on two unexplored while fundamentally important scenarios, missing tag detection in the presence of unexpected tags and in multiple-group multiple-region RFID systems. In the first scenario, we develop a Bloom filter-based protocol. In the second scenario, we develop three protocols by incorporating an improved version of the Bloom filter design.
13

Solutions novatrices pour l'amélioration du taux de lecture de tags RFID UHF dans des environnements complexes / Innovations and solutions for the read rate improvement of UHF RFID tags in complex environments

Quiroz Moreno, Rafael Antonio 04 March 2014 (has links)
L'identification par radio fréquence (RFID) est une technologie utilisant les ondes radio pour détecter, localiser et identifier des objets sur lesquels on place des étiquettes électroniques ou tags. Cette technologie, avec des fonctionnalités de détection supérieures à 2m, est destinée à remplacer le code-barre existant depuis les années 1970. Durant la dernière décennie, le développement de la RFID UHF a permis d'élargir le domaine des applications qui compte entre autres le marquage d'objets, le contrôle d'accès, la traçabilité, la logistique, l'inventaire, et même les transactions financières. Avec cette augmentation de la demande de services d'identification, les prévisions pour le marché de la RFID (actuellement dans les 12MM d'euros) montrent une augmentation de 3MM d'euros par an dans les 10 prochaines années. Actuellement la RFID UHF présente plusieurs limitations technologiques fortes expliquant que son développement est moins rapide que ce qui avait été envisagé il y a une vingtaine d'années. Deux problématiques industrielles importantes sont abordées dans ce travail. Tout d'abord la variété des supports sur lesquels les étiquettes RFID sont placées, cette variabilité des supports entraînant un déréglage des antennes des tags à cause du changement de la permittivité électrique et/ou de la conductivité du milieu. Dans ce contexte des solutions sont proposées au niveau de tags UHF pour une application sur surfaces en plastique ou en métal. La deuxième problématique est liée au couplage entre antennes lorsque la densité de tags est forte ou aux perturbations de diagramme (masquage) dues à l'environnement proche des antennes. Afin d'améliorer le taux de lecture dans ces conditions, une antenne lecteur miniaturisée à quatre IFAs intégrant de la diversité d'espace, de polarisation et de diagramme a été développée et testée dans un scénario à forte densité de tags / Radio Frequency Identification (RFID) is a technology designed to use the electromagnetic waves backscattering to establish detection and identification for different types of articles. Due to its longer coverage range, this technology seeks to replace the bars code existing since 1970. Recently RFID developments allow the growth in the number of applications including access control, tracking and logistic, inventory, and even electronic contactless payment between others. With this growing in the RFID services demand, the market value previsions (currently in 12MM euros) show an increase of 3MM euros per year during the next 10 years. Nowadays the RFID has many technical limitations that could explain the fact of the slow growth different of the initial estimation twenty years ago. Two main issues in RFID field are treated in this work. Initially, the variety of supports where the tags are placed on, fact that produce an antenna mismatch due to the electrical permittivity variation. For this problem some UHF tags solutions are developed and proposed to enhance the antennas performance for plastic and metallic supports applications. The second issue which is the low detection rate is clearly linked to the antennas coupling when the tags density is high or to the perturbations in the reader's radiation pattern due to the environment next to the antenna. In order to improve the detection-identification rate in these conditions, a four IFA miniaturized reader antenna with diversity is developed and tested
14

Användning av RFIDi plastpallar inom det interna flödet / Utilization of RFID in plastic pallets within the internal flow

Manojlovski, Damjan, Mezher, Mohammed January 2024 (has links)
Det här är en kvalitativ studie som syftar till att undersöka användningen av RFID-teknik i det interna flödet hos en verksamhet i lagerbranschen. Det som undersöktes var hur tekniken kan effektivisera verksamheten och vilken potential som finns med RFID där ämnet realtidsspårning introduceras. Tillsammans med antenner och läsare så möjliggör RFID-teknik identifiering och spårning av lastbärare genom radiofrekvenser vilket gör det till en resurs med hög potential. För att spåra lastbärare används RFID-teknik genom att varje lastbärare utrustas med en unik RFID-tagg.  Fördelarna med att implementera RFID-teknologi inkluderar spårbarhet och synlighet i det interna flödet vilket leder till minskade förluster av lastbärare och en potential till att korta ner ledtider och öka effektiviteten i verksamheten. Hinder som höga initiala investeringskostnader och komplexitet i integration kan identifieras vid implementeringen. För att optimera utnyttjandet av RFID-teknologi för användning och för spårning så föreslås utvecklingar inom området så att fler aktörer ska kunna implementera tekniken och möjliggöra en förbättrad spårning längs värdekedjan. Fallföretaget har sedan två år tillbaka börjat med användning av plastpallar med RFID-taggar i sin verksamhet för att tillfredsställa sina kunder.  Studien bekräftar att trots vissa utmaningar med RFID-teknologin så erbjuder tekniken fördelar som minskad risk för mänskliga fel och bättre hantering och spårbarhet av lastbärare. Avslutningsvis har den här studien visat att användningen av RFID i plastpallar erbjuder signifikanta möjligheter att förbättra interna logistikprocesser. Våra resultat bidrar till såväl den akademiska diskussionen som till praktiska tillämpningar, och stärker förståelsen för hur moderna teknologier kan användas för att driva effektivitet och innovation inom logistiksektorn. / This is a qualitative study aimed at investigating the use of RFID technology in the internal flow of a warehouse. The study examined how the technology can streamline operations and the potential of RFID, particularly in real-time tracking. Alongside antennas and readers, RFID technology enables the identification and tracking of carriers or pallets through radio frequencies, making it a resource with high potential. To track pallets, RFID technology is utilized by equipping each pallet with a unique RFID tag.  The advantages of implementing RFID technology include traceability and visibility in the internal flow, leading to reduced losses of carriers and the potential to shorten lead times and increase efficiency in warehouse operations. Challenges such as high initial investment costs and integration complexity may be identified during implementation. To optimize the utilization of RFID technology for tracking and usage, developments in the field are proposed to enable more actors to implement the technology and facilitate improved tracking along the value chain. The case company has been using plastic pallets with RFID-tags in its operations for the past two years to satisfy customer demands.  The study confirms that despite some challenges with the accuracy of RFID technology, the technology offers significant advantages for modern logistics. The study confirms that despite some challenges with the accuracy of RFID technology, it offers significant advantages for modern logistics systems. The conclusion emphasizes the importance of further research and development to fully leverage the potential of RFID technology in the future.
15

RFID應用對企業內部控制影響之研究 / A Study of RFID Effects on Enterprise Internal Control

江美英, Mei Ying ,Chiang Unknown Date (has links)
當企業引進新科技應用時,除了看到新科技所帶來提升品質、降低成本、創造營收各種正面的效益外。管理者及稽核控制人員心中難免有所疑惑,真的沒有負面的影響嗎? 是不是會因為新科技的引進造成其他管理控制的問題,會不會產生更多經營的風險? 會不會影響到營運績效與效果、財務報表的可靠性及法令的遵循。是不是要設計更多的新的控制活動或調整現行管理控制模式來降低新技術引進所產生的風險。這都是令人困擾及擔憂的議題。 本研究針對RFID已經發展的應用的方向,來歸納RFID的管理控制特性。並將這些特性與影響內部控制規劃與執行時所面臨的困擾與弱點進行研究。尋找可否透過RFID的導入來改善這些困擾及弱點。從本研究結論來看,RFID的應用在規劃面有正面的影響。亦就是企業引進RFID可以改善營運風險的控制。而且從內部控制執行面的-銷售及收款循環、採購及付款循環及生產循環的弱點來研究分析,RFID亦可以改善跟杜絕某些企業常發生的控制缺點。 因此本研究顯示,企業導入RFID不只是在物流管理的提升服務品質、縮短處理時間、降低人工成本、確保資產安全這些效益外,RFID對企業的內部控制設計及執行更有意想不到的效益。因此企業在評估導入RFID時,對於應用的效益部份絕對可以增加一項,『改善企業控制環境、提升控制效率』。 / While new technology is applied to an enterprise, do either the managerial level or the auditor doubt of any negative effects besides its positive effects to improve quality, to bring down cost and to boost up revenue? Will the newly-introduced technology cause any other managerial or controlling problems? Will it create more risks in running a business? Will it affect the operational performances and results, the reliability of financial reports and the compliance of laws and regulations? Are there more new controlling activities need to be designed or the existing managerial controlling model needs to be adjusted to reduce risks caused by these new applied technologies? The above mentioned are really obsessive and worrying issues. This research paper is to induce the managerial control properties of RFID in accordance with its existing applications. The purpose is to analyze the founded properties, the effects of internal audit control and the weak points confronted during implementation, hence to look for the improvement through the application of RFID. The conclusion of this research showed that the application of RFID did cause the positive effects. In other words, the introduction of RFID in an enterprise will reduce operational risks. Also the analysis of the weak points of internal audit control (Revenue Cycle, Buying Cycle and Production Cycle), also revealed the introducing of RFID will reduce and eliminate some frequently happened controlling defects in an enterprise. This research revealed that the application of RFID in an enterprise will not only enhance the quality of logistic management, but will also shorten the time of job processing, reduce the labor cost, ensure the safety of assets and other unexpected benefits during the design and implementation of internal audit control of an enterprise. Thus during the assessment of RFID application in an enterprise, it is unquestionably to add ‘improvement of control environment’ and ‘enhancement of control efficiency’ to its advantages.
16

Design of Passive UHF RFID Tag Antennas and Industry Application

Wu, Xunxun January 2010 (has links)
Nowadays, there is a growing demand for reliable assets security and management in various industries. The company SolarWave is eager to implement a comprehensive security system to produce active protection for their expensive product: solar panels. This security system is not only including assets tracking, monitoring but also combined with a control system, which is used to binary control a switch of solar panel to be on in presence of the correct ID and off in absence of the correct ID. One of the technologies that made this concept viable is known as Radio Frequency Identification (RFID). The thesis project is a sub-project in the development project whose content is mentioned as above. It contains two main parts. One is the system solution for the company. The other is RFID tag design which is in parallel with the company solution in order to reach a scientific level of a master thesis. In this thesis, I systematically analyze the operating mechanism and characteristics of RFID, and propose both active and passive RFID solutions for the company. And I also suggest an alternative radio technology ZigBee which can be used instead or as a complement to RFID. Meanwhile, I propose two designs of RFID tag according to the specification of the solar panel. One is modified meandering antenna. This kind of antenna is very effective and popular in RFID tag design in order to minimize the size of antenna. The other is inductively coupled loop antenna. It is a very useful method for conjugate matching in RFID tag antenna. The required input resistance and reactance can be achieved separately by choosing appropriate geometry parameters. It makes the antenna easier to match to the tag chips. Both the RFID antenna designs are simulated on Ansoft HFSS 12.
17

Cloning Prevention Protocol for RFID

Shah, Jignasa 09 December 2010 (has links)
Radio Frequency Identification (RFID) is an emerging area under ubiquitous computing. RFID benefits include multiple read/write, longer read range and no requirement for line of sight. Due to security and privacy issues, RFID is not as popular as it should be. Tag cloning is one of the biggest threats to RFID systems. Easy access to RFID tags allows an attacker to replicate the tags and insert duplicate tags into the system. An RFID tag cloning attack can lead to access control or financial frauds in areas like supply chain management and government issued IDs. In this thesis, a cloning prevention protocol is proposed. It uses light weight functions such as Pseudo Random Number Generator (PRNG) and compare function. A 3-way handshake with a secret key, frequency hopping mechanism and dynamic fake ID makes this protocol a secure authentication mechanism.
18

RFID-gestützte Produktempfehlung im stationären Einzelhandel /

Hansen, Torben. January 2008 (has links)
Diss--Universität des Saarlandes.
19

Contribution à la recherche de topologies d'antennes pour des applications RFID / Antanna design contribution for RFID tag on UHF frequency band

Chaabane, Hamza 03 December 2012 (has links)
Les travaux de recherche s'inscrivent dans le cadre du projet intitulé « PAC-ID Grande Distribution » du Pôle de compétitivité « Solutions Communicantes Sécurisées ». Ce projet, d'une durée de trente mois, vise à promouvoir le déploiement en volume de la technologie RFID en bande UHF dans le secteur de la grande distribution. Il rassemble plusieurs entreprises ayant un rôle clé dans le domaine de la RFID. En effet, comme utilisateur potentiels finaux de la technologie RFID, on retrouve aussi bien un acteur important du monde de la grande distribution, en l'occurrence l'entreprise Carrefour, qu'un représentant des PME, Malongo. Les entreprises IBM et Orange se focalisent sur la gestion de données RFID et l'implémentation du système informatique. A côté de cela, une nouvelle génération de puces RFID est développée par la société ST Microelectronics. L'expertise des sociétés IER et TAGSYS dans le domaine de la fabrication aussi bien d'étiquettes que de lecteurs RFID permet de faire le lien entre l'ensemble de ces acteurs et d'apporter des réponses techniques aux différents besoins métiers exprimés. A l'intérieur de ce projet d'envergure, l'intervention du Laboratoire de Conception et d'Intégration des Systèmes (LCIS) sur un plan d'avantage exploratoire, a consisté à développer un procédé original de conception automatisé de tags RFID adaptés aux contraintes de la grande distribution. Ce travail nous a permis de monter les performances de la méthodologie de conception d'antennes pour les tags RFID en bande UHF introduite. Une application permettant d'automatiser la conception d'antennes basées sur l'utilisation d'un logiciel de simulation RF a été introduite. Cette application pourrait parfaitement être implémentée sur le logiciel lui-même afin de venir compléter les outils de CAO déjà présent. / The research is part of the project entitled "PAC-ID Grande Distribution" under the competitiveness cluster "Secured Communicating Solutions". This project, for a period of thirty months, aims to promote the UHF RFID mass volume deployment for retail application. It brings together several companies with an important work in the RFID field. Indeed, as a potential end user of the RFID technology, there is a major player in the world of retail, in this case the company Carrefour, a representative of Malongo. IBM and Orange companies focus on data management and RFID system implementation. Besides, a new RFID chip generation is developed by ST Microelectronics. The expertise of companies IER and TAGSYS in the field of manufacturing labels and readers can make the connection between all of these actors and technical answers to different business needs expressed. Within this major project, the contribution of the Laboratory LCIS is to develop a novel method of automated design of RFID tags suitable for constraints supermarkets. This work has allowed us to raise the performance of the introduced antenna design methodology for RFID tags at UHF band. An application to automate the antenna design based on the use of RF simulation software was introduced, tested and validated. This could well be implemented on the software itself to complete the CAD tools already present.
20

Diseño del sistema de control de asistencia en la agencia mercado de la Caja Huancayo aplicando tarjetas de proximidad de tecnología RFID

Martinez Verand, Rodolfo Steven 30 May 2018 (has links)
El presente informe final de tesis muestra el diseño de un sistema de control de asistencia en la agencia mercado de la Caja Huancayo aplicando Tarjetas de proximidad de Tecnología RFID específicamente para mejorar el control de los registros de asistencia del personal de la Caja Huancayo con la finalidad de agilizar este proceso que actualmente se conlleva con malas prácticas de los colaboradores.

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