• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 298
  • 105
  • 94
  • 78
  • 68
  • 55
  • 21
  • 18
  • 18
  • 15
  • 13
  • 9
  • 7
  • 7
  • 5
  • Tagged with
  • 886
  • 164
  • 142
  • 133
  • 127
  • 105
  • 91
  • 79
  • 74
  • 71
  • 70
  • 68
  • 63
  • 62
  • 61
  • 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.
91

Design and Implementation of an Augmented RFID System

Borisenko, Alexey January 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.
92

Méthode de conception et d'optimisation d'éléments rayonnants de cartes à puce pour applications en RFID HF / Design and optimization method of radiating elements dedicated to HF RFID smart cards

Mourad, Oumar 07 November 2014 (has links)
La bande de fréquence HF est une bande internationale de plus en plus utilisée de par le monde pour des applications RFID (Radio Frequency IDentification). Les nombreuses applications telles que le suivi, l'emballage, le transport, et la détection ont en effet suscité un intérêt grandissant pour la RFID sans contact en champ proche à 13,56 MHz basée sur la norme de communication ISO/IEC 14443. Pour les systèmes RFID HF à faible coût, les interfaces de communication lecteurs/étiquettes utilisent des antennes boucles inductives formées par l'enroulement de fils ou de bandes conductrices. Dans cette thèse, nous nous intéressons plus particulièrement à la conception et à l’optimisation de l’antenne de l’étiquette utilisée comme ticket de transport pour fournir le maximum d’énergie au circuit intégré. Nous analysons plus particulièrement l’influence des paramètres géométriques et les matériaux de fabrication de l’élément rayonnant afin de proposer une méthodologie de conception d’antenne inductive. Pour ce faire, une modélisation circuit du système RFID HF est proposée afin d’effectuer une meilleure analyse du couplage lecteur/étiquette ainsi que des points critiques de fonctionnement. Afin de valider les différentes études effectuées, de nombreux prototypes d’antennes ont été réalisés avec différents matériaux et les résultats obtenus analysés. / The HF frequency band is internationally allocated for worldwide and fastest growing band used in RFID (Radio Frequency IDentification) applications. The need for automation and advanced technologies in applications like tracking, packaging, transportation, and sensing has attracted the interest of the near-field contactless RFID at 13.56 MHz based on ISO/IEC 14443 communication standard. For low-cost RFID HF systems, communication interfaces use inductive loop antennas made up of the winding of conductive wires or strips. In this thesis, we are particularly interested in the antenna design and optimization of tags dedicated for transport to provide a maximum power to the integrated circuit. The influence of the geometric parameters and materials used for the realization of the radiating element has been particularly studied to reach to propose a methodology of inductive antennas design. To do this, a circuit model of HF RFID system has been proposed to analyze the reader / tag coupling and the different critical operating points. Several antenna prototypes were made with different materials to validate the different studies.
93

Přístupový bezpečnostní systém mobilního zařízení na principu RFID / Access security system of mobile davice on RFID principle

Petrušek, Marek January 2013 (has links)
This thesis discusses the model of security access with the use of microcontroller and RFID reader.The model is designed for utilization in automobiles,in which it will have the properties of a an immobilizer and also the function of saving the time and ID of the chip in use.For application in automobiles the minimalization of consumption of the mobile device is also described.This thesis is a part of project IGA VUT Brno,FSI-S-11-31,Application of artificial intelligence methods.
94

Design and Optimization of Passive UHF RFID Tag Antenna for Mounting on or inside Material Layers

Shao, Shuai 08 October 2015 (has links)
No description available.
95

RFID Tag Design and Range Improvement

Chirammal Ramakrishnan, Rijwal 27 June 2012 (has links)
Radio Frequency Identification (RFID) is a short range radio technology for communication between two objects namely, a reader and a tag. Design of an RFID tag with the best range is always the motive of an RFID designer. In this thesis two RFID tags were simulated, designed and manufactured. The first one is a semi-passive RFID tag, which also serves as a discrete prototype tag for the research group to master RFID tag designs. The user can program and further extend the use of this tag according to the requirements. This RFID tag is provided with JTAG interface to program and debug. The read range of this prototype tag is found to be 1m with reader EIRP of 30dBm. The second design is a passive tag which can be commercialized. It achieves a competitive read range of 2.9m for reader EIRP of 21dBm. The read range when measured in a practical implementation inside a building corridor was 15m.
96

Experiências baseadas na localização em dispositivos móveis

Alves, António Duarte Paiva January 2009 (has links)
Estágio realizado na Ubiwhere - Inova Ria e orientado pelo Eng.º Rui Costa / Tese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 2009
97

CPFR於3C流通業應用之研究 / A study on the application of CPFR for 3C distributor

陳銘驥 Unknown Date (has links)
企業採用RFID將是一種未來的趨勢,它受到環境、技術、組織等因素的影響,都將牽動企業採用RFID技術的速度和廣度。本研究將從企業採用新技術的應用考量因素,尤其是大量使用條碼的商業流程,若導入RFID的應用,勢必對原有作業產生極大的影響。其次是它帶來的效益不是只有技術的引進,而是必須在整個作業流程上要有所突破,佐以另外的作業流程改變。因此如何應用CPFR的架構模型導入3C流通業,才是真正能達成RFID技術的被採用。 自從VICS(The Voluntary Inter-industry Commerce Standards)於1988 年提出協同規劃、預測與補貨(Collaborative Planning, Forecasting and Replenishment;CPFR)後,目前台灣3C 流通業導入CPFR 模式的應用尚在起步階段。因此本研究將依據VICS 所提出的CPFR 九大步驟,輔以個案公司的實際執行狀況,來探討CPFR 模式是否適用於目前國內的3C 流通業。 本研究發現,個案公司在實際導入CPFR 後,確實能減少庫存、提高商品的週轉率及降低不必要的人工作業時間,但另方面卻發現CPFR並沒有顧及到兩個重要議題為:製造商與零售商的預測尚未整合、協同合作是從開出訂單後才開始的問題。另一方面,本研究也發現 CPFR 在中小企業林立的台灣因受到營運成本、專業人員流動大、技術更新及管理不易的限制,加上企業間原本就互信基礎薄弱及資訊與利益的分享無法建立共識之下有執行上的困難。因此,本研究將以一個合理的假設情境,從個案導入的過程中,分析供應商從通路商的銷售端 ( CRM 資料庫)中取得訂單預測與存貨管理的狀況,結果發現以 CPFR 模式執行,不但在銷貨及訂單的預測比傳統模式更加精確,尚可以降低門市庫存的波動、減少通路商的安全庫存及存貨的成本,避免供應鏈中「長鞭效應」(bullwhip effect) 的發生,真正達到 RFID 的功效,也驗證了 CPFR 架構的必要性。 / Using RFID will be one kind of trend in the future among the enterprises. It is affected by enviorment, technology and organization. All factors will affect using speed and breadth of the enterprises. This study considerate the factors of the enterprises applying new technology, especially heavy use of bar code business process. If RFID is applied, it must be a greatly impacts among the existing operation. Second, the benefits of using RFID are not only the application of new technology, but also a breakthrough of the whole processes. Therefore, the structure of how to apply CPFR model into 3C logistic business is the key factor to make the RFID technology applied successfully. Since 1988, the VICS (The Voluntary Inter-industry Commerce Standards) proposed CPFR (Collaborative Planning, Forecasting and Replenishment), the application of CPFR in 3C logistic business in Taiwan is in the beginning. Therefore, this study would base on the nine steps of CPFR proposed bu VICS, supplemented by cases of actual applied status of company, to explore whether the CPFR model is suitable for 3C logistic business in Taiwan or not. This study discovers that case company can reduce the inventorys, enhance the turnover rate and reduces the nonessential operating time after CPFR model is applied. But on the other hand, there are two important issues were not taken into consideration in CPFR model: the forcasts of manufacturers and retail merchants are not integrated, and collaborative cooperation is beginning after orders are placed. Besides, applying CPFR is difficult because of following reasons. Small and medium enterprises (SEMs) are so many in Taiwan, and they have the limitation of operating cost, the changes of spceialists, update of new technology and management difficulties, in addition to the weak on the mutual confidence foundation and few in common of sharing the information and benefits. Consequensely, base on a reasonable assumption, in the process of CPFR applied, this study analyze the situation of order forcasts and inventory management which are got from retailers (CRM database) by suppliers. The result finds out that executing in CPFR model, not only the forcasts of selling and orders are more precise than traditional model, but also the volatility of inventories and the cost of safety inventory can be reduced. The bullwhip effect in supply chain can be avoided, achieving the effect of RFID and the necessity of CPFR constructure is confirmed.
98

Selektivt larmsystem

Cronholm, Simon, Zelejakovic, Faruk, Olofsson, Mikael January 2003 (has links)
No description available.
99

RFID Tag Design and Range Improvement

Chirammal Ramakrishnan, Rijwal 27 June 2012 (has links)
Radio Frequency Identification (RFID) is a short range radio technology for communication between two objects namely, a reader and a tag. Design of an RFID tag with the best range is always the motive of an RFID designer. In this thesis two RFID tags were simulated, designed and manufactured. The first one is a semi-passive RFID tag, which also serves as a discrete prototype tag for the research group to master RFID tag designs. The user can program and further extend the use of this tag according to the requirements. This RFID tag is provided with JTAG interface to program and debug. The read range of this prototype tag is found to be 1m with reader EIRP of 30dBm. The second design is a passive tag which can be commercialized. It achieves a competitive read range of 2.9m for reader EIRP of 21dBm. The read range when measured in a practical implementation inside a building corridor was 15m.
100

Selektivt larmsystem

Cronholm, Simon, Zelejakovic, Faruk, Olofsson, Mikael January 2003 (has links)
No description available.

Page generated in 0.0275 seconds