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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.
171

Design och implementering av enhandsburen RFID-läsare / Design and implementation of a handheld RFID-reader

Nordström, Edward, Hollander, Johan January 2008 (has links)
Radio frequency identification (RFID) is a versatile wireless technology usedworldwide. The fields of applications are many and its popularity constantlygrows due to smaller in size, better and less expensive components. RFID isused to identify, track or share information about an object using radio waves. This master thesis describes the process of designing and implementing ahandheld UHF RFID reader. The goal was to, based on a UHF RFID-chipdesign a fully functional, small in size and power efficient device. Amicrocontroller provides the user interface and is also used to control theRFID-chip and a Bluetooth device. A Bluetooth- and GPRS-compatible mobilephone will be used to forward data to a server connected to the Internet. Allparts of the design are described, such as the printed circuit board design aswell as the software for the micro controller and the mobile phone. Because the extent of this thesis it is neither possible nor necessary to dig toodeep into the Bluetooth- or GPRS-protocol. The focus will be on designingsoftware and hardware for the handheld unit. / Radio frekvens identifiering (RFID) är en mångsidig trådlös teknik somanvänds över hela världen. Områdena där tekniken används är många och dess popularitet växer konstant tack vare mindre storlek, bättre och billigarekomponenter. RFID används för att identifiera, spåra eller dela med siginformation om ett objekt med radiovågor. Det här examensarbetet beskriver processen av design och implementering aven handburen UHF RFID läsare. Målet har varit att, baserat på ett UHF-RFIDchip, designa en fullt fungerande, liten och strömsnål enhet. En microcontroller förser dels användaren med ett användargränssnitt och sköter delskommunikationen med RFID chip och en blåtandsmodul. En blåtands- ochGPRS- eller 3G-kompatibel mobiltelefon används for att skicka vidare data tillen server kopplad till Internet. Alla delar av designen är beskrivna, så som PCB design, mjukvara för micro controllern och mobiltelefonen. På grund av omfattningen av det här examensarbetet så har det inte varitmöjligt eller nödvändigt att gräva för djupt i Blåtands- eller GPRS/3Gprotokollen. Fokus är på att designa hårdvara och mjukvara för den handhållna enheten.
172

Design och implementering av enhandsburen RFID-läsare / Design and implementation of a handheld RFID-reader

Nordström, Edward, Hollander, Johan January 2008 (has links)
<p>Radio frequency identification (RFID) is a versatile wireless technology usedworldwide. The fields of applications are many and its popularity constantlygrows due to smaller in size, better and less expensive components. RFID isused to identify, track or share information about an object using radio waves.</p><p>This master thesis describes the process of designing and implementing ahandheld UHF RFID reader. The goal was to, based on a UHF RFID-chipdesign a fully functional, small in size and power efficient device. Amicrocontroller provides the user interface and is also used to control theRFID-chip and a Bluetooth device. A Bluetooth- and GPRS-compatible mobilephone will be used to forward data to a server connected to the Internet. Allparts of the design are described, such as the printed circuit board design aswell as the software for the micro controller and the mobile phone.</p><p>Because the extent of this thesis it is neither possible nor necessary to dig toodeep into the Bluetooth- or GPRS-protocol. The focus will be on designingsoftware and hardware for the handheld unit.</p> / <p>Radio frekvens identifiering (RFID) är en mångsidig trådlös teknik somanvänds över hela världen. Områdena där tekniken används är många och dess popularitet växer konstant tack vare mindre storlek, bättre och billigarekomponenter. RFID används för att identifiera, spåra eller dela med siginformation om ett objekt med radiovågor.</p><p>Det här examensarbetet beskriver processen av design och implementering aven handburen UHF RFID läsare. Målet har varit att, baserat på ett UHF-RFIDchip, designa en fullt fungerande, liten och strömsnål enhet. En microcontroller förser dels användaren med ett användargränssnitt och sköter delskommunikationen med RFID chip och en blåtandsmodul. En blåtands- ochGPRS- eller 3G-kompatibel mobiltelefon används for att skicka vidare data tillen server kopplad till Internet. Alla delar av designen är beskrivna, så som PCB design, mjukvara för micro controllern och mobiltelefonen.</p><p>På grund av omfattningen av det här examensarbetet så har det inte varitmöjligt eller nödvändigt att gräva för djupt i Blåtands- eller GPRS/3Gprotokollen. Fokus är på att designa hårdvara och mjukvara för den handhållna enheten.</p>
173

Radio frequency identification for the measurement of overhead power transmission line conductors sag

Hlalele, Tlotlollo Sidwell 07 1900 (has links)
This dissertation deals with the challenge of power utility in South Africa which is on proactive detection of fallen power line conductors and real time sagging measurement together with slipping of such conductors. Various methods which are currently used for sag detection were characterized and evaluated to the aim of the research. A mathematical reconstruction done to estimate the lowest point of the conductor in a span is presented. Practical simulations and application of radio frequency identification (RFID) for sag detection is attempted through matlab software. RFID radar system is then analyzed in different modes and found to give precision measurement for sag in real time as opposed to global positioning system (GPS) if one dimension of the tag assumed fixed on the power line. Lastly errors detected on the measurements are corrected using a trainable artificial neural network. A conclusion is made by making recommendations in the advancement of the research. / Electrical Engineering / M. Tech. (Electrical Engineering)
174

Sistema telemétrico com tecnologia RFID para medição de pressão

Luis, Hamilton Costa 17 September 2010 (has links)
A necessidade da medicina por equipamentos eletrônicos portáteis, menores, confiáveis e baratos favorece o desenvolvimento de técnicas biotelemétricas passivas de monitoração nas aplicações biomédicas invasivas. Nesse trabalho são apresentados o desenvolvimento e o teste de um dispositivo sensor biotelemétrico passivo, que utiliza a tecnologia de identificação por radio freqüência - RFID (Radio Frequency Identification). O dispositivo desenvolvido, comumente chamado como tag, é comporto basicamente por três partes: a arquitetura RFID utilizada para baixa freqüência, a unidade de controle responsável pelo processamento dos dados e a unidade sensora responsável pela monitoração da pressão arterial. Como o tag e passivo, ou seja, não contém baterias, para que seja ativado é necessário um aparelho que faça sua energização e também decodifique os dados por ele transmitidos. Este aparelho que faz a leitura e envia um sinal para ativar o transponder é comumente chamado de leitora. A leitora utilizada neste projeto terá seu firmware adaptado de forma a processar o valor da pressão enviada pelo tag. São abordados neste trabalho tanto a modelagem teórica do sistema quanto a especificação prática dos componentes para os testes de validação. Na modelagem teórica são apresentados os modelos matemáticos comportamentais do sistema. Os resultados obtidos validam a metodologia utilizada para o desenvolvimento de um sensor RFID passivo que tem como finalidade mensurar a pressão arterial. / The need of medicine for portable electronic equipments smallers [sic], reliables [sic] and inexpensive supports the development of biotelemetry techniques passive monitoring in invasive biomedical applications. In this work are presents [sic] the development and testing of a passive biotelemetry sensor device, which uses the technology of Radio Frequency Identification - RFID. The developed device, commonly referred to as the tag, is basically composed of three parts: the RFID architecture used for low frequency, the control unit responsible for data processing and sensor unit responsible for monitoring blood pressure. As the tag is passive i.e. does not contain batteries to activate it, It [sic] is necessary a device that makes its energizing and also decode the data transmitted by it. This device that reads and sends a signal to activate the transponder is commonly called a reader. The reader used in this project will have its firmware adapted to handle the pressure value sent by the tag. This work also presents theoretical modeling of the system and the specification of components for practicing the validation tests. In theoretical modeling are presented mathematical models of system behavior. The results validate the methodology used for the development of passive RFID sensor that aims to measure blood pressure.
175

Sistema telemétrico com tecnologia RFID para medição de pressão

Luis, Hamilton Costa 17 September 2010 (has links)
A necessidade da medicina por equipamentos eletrônicos portáteis, menores, confiáveis e baratos favorece o desenvolvimento de técnicas biotelemétricas passivas de monitoração nas aplicações biomédicas invasivas. Nesse trabalho são apresentados o desenvolvimento e o teste de um dispositivo sensor biotelemétrico passivo, que utiliza a tecnologia de identificação por radio freqüência - RFID (Radio Frequency Identification). O dispositivo desenvolvido, comumente chamado como tag, é comporto basicamente por três partes: a arquitetura RFID utilizada para baixa freqüência, a unidade de controle responsável pelo processamento dos dados e a unidade sensora responsável pela monitoração da pressão arterial. Como o tag e passivo, ou seja, não contém baterias, para que seja ativado é necessário um aparelho que faça sua energização e também decodifique os dados por ele transmitidos. Este aparelho que faz a leitura e envia um sinal para ativar o transponder é comumente chamado de leitora. A leitora utilizada neste projeto terá seu firmware adaptado de forma a processar o valor da pressão enviada pelo tag. São abordados neste trabalho tanto a modelagem teórica do sistema quanto a especificação prática dos componentes para os testes de validação. Na modelagem teórica são apresentados os modelos matemáticos comportamentais do sistema. Os resultados obtidos validam a metodologia utilizada para o desenvolvimento de um sensor RFID passivo que tem como finalidade mensurar a pressão arterial. / The need of medicine for portable electronic equipments smallers [sic], reliables [sic] and inexpensive supports the development of biotelemetry techniques passive monitoring in invasive biomedical applications. In this work are presents [sic] the development and testing of a passive biotelemetry sensor device, which uses the technology of Radio Frequency Identification - RFID. The developed device, commonly referred to as the tag, is basically composed of three parts: the RFID architecture used for low frequency, the control unit responsible for data processing and sensor unit responsible for monitoring blood pressure. As the tag is passive i.e. does not contain batteries to activate it, It [sic] is necessary a device that makes its energizing and also decode the data transmitted by it. This device that reads and sends a signal to activate the transponder is commonly called a reader. The reader used in this project will have its firmware adapted to handle the pressure value sent by the tag. This work also presents theoretical modeling of the system and the specification of components for practicing the validation tests. In theoretical modeling are presented mathematical models of system behavior. The results validate the methodology used for the development of passive RFID sensor that aims to measure blood pressure.
176

Design and implementation of an inventory management system in libraries using radio frequency identification technology

Mvoulabolo, Meryle K. 12 December 2019 (has links)
M. Tech. (Department of Process Control and Computer Systems, Faculty of Engineering and Technology), Vaal University of Technology. / Radio Frequency Identification Technology (RFID) technology is increasingly being used in multiple applications due to its low cost and ability to provide a high quality of identification. The cost benefit of RFID system is seen in the reduction in labor required to perform routine tasks such as inventory. With RFID, inventory-related tasks can be done in substantially less time compared to other commonly used auto-identification systems. Recent research has illustrated the application of RFID in multiple application scenarios. RFID can be used for real-time patient identification and monitoring in hospitals, but also for product expiration-date management in retail industries. Some enterprises in South Africa uses a combination of RFID technology and Internet of Things (IoT) to detect misplaced products and to detect low stock levels. Furthermore, RFID is also used for inventory management in libraries as discussed in this dissertation. In this dissertation, a combination of RFID and ZigBee technologies was used to reduce the time spent to perform inventory in libraries. An inventory management system was designed, simulated and built in order to count and locate books inside a library hence improving inventory process time in libraries. The overall results were satisfactory which lead to the achieving of the objectives set in this study.
177

The design and development of multi-agent based RFID middleware system for data and devices management

Massawe, Libe Valentine January 2012 (has links)
Thesis (D. Tech. (Electrical Engineering)) - Central University of technology, Free State, 2012 / Radio frequency identification technology (RFID) has emerged as a key technology for automatic identification and promises to revolutionize business processes. While RFID technology adoption is improving rapidly, reliable and widespread deployment of this technology still faces many significant challenges. The key deployment challenges include how to use the simple, unreliable raw data generated by RFID deployments to make business decisions; and how to manage a large number of deployed RFID devices. In this thesis, a multi-agent based RFID middleware which addresses some of the RFID data and device management challenges was developed. The middleware developed abstracts the auto-identification applications from physical RFID device specific details and provides necessary services such as device management, data cleaning, event generation, query capabilities and event persistence. The use of software agent technology offers a more scalable and distributed system architecture for the proposed middleware. As part of a multi-agent system, application-independent domain ontology for RFID devices was developed. This ontology can be used or extended in any application interested with RFID domain ontology. In order to address the event processing tasks within the proposed middleware system, a temporal-based RFID data model which considers both applications’ temporal and spatial granules in the data model itself for efficient event processing was developed. The developed data model extends the conventional Entity-Relationship constructs by adding a time attribute to the model. By maintaining the history of events and state changes, the data model captures the fundamental RFID application logic within the data model. Hence, this new data model supports efficient generation of application level events, updating, querying and analysis of both recent and historical events. As part of the RFID middleware, an adaptive sliding-window based data cleaning scheme for reducing missed readings from RFID data streams (called WSTD) was also developed. The WSTD scheme models the unreliability of the RFID readings by viewing RFID streams as a statistical sample of tags in the physical world, and exploits techniques grounded in sampling theory to drive its cleaning processes. The WSTD scheme is capable of efficiently coping with both environmental variations and tag dynamics by automatically and continuously adapting its cleaning window size, based on observed readings.
178

Interactive RFID for Industrial and Healthcare Applications

Shen, Jue January 2015 (has links)
This thesis introduces the circuit and system design of interactive Radio-Frequency Identification (RFID) for Internet of Things (IoT) applications. IoT has the vision of connectivity for anything, at anytime and anywhere. One of the most important characteristics of IoT is the automatic and massive interaction of real physical world (things and human) with the virtual Internet world.RFID tags integrated with sensors have been considered as one suitable technology for realizing the interaction. However, while it is important to have RFID tags with sensors as the input interaction, it is also important to have RFID tags with displays as the output interaction.Display interfaces vary based on the information and application scenarios. On one side, remote and centralized display interface is more suitable for scenarios such as monitoring and localization. On the other side, tag level display interface is more suitable for scenarios such as object identification and online to offline propagation. For tag level display, though a substantial number of researches have focused on introducing sensing functionalities to low power Ultra-High Frequency (UHF) RFID tags, few works address UHF RFID tags with display interfaces. Power consumption and integration with display of rigid substrate are two main challenges.With the recent emerging of Electronic Paper Display (EPD) technologies, it becomes possible to overcome the two challenges. EPD resembles ordinary ink on paper by characteristics of substrate flexibility, pattern printability and material bi-stability. Average power consumption of display is significantly reduced due to bi-stability, the ability to hold color for certain periods without power supplies. Among different EPD types, Electrochromic (EC) display shows advantage of low driving voltage compatible to chip supply voltage.Therefore this thesis designs a low power UHF RFID tag integrated in 180 nm CMOS process with inkjet-printed EC polyimide display. For applications where refresh rate is ultra-low (such as electronic label in retailing and warehouse), the wireless display tag is passive and supplied by the energy harvested from UHF RF wave. For applications where refresh rate is not ultra-low (such as object identification label in mass customized manufacturing), the wireless display tag is semi-passive and supplied by soft battery. It works at low average power consumption and with out-of-battery alert. For remote and centralized display, the limitations of uplink (from tags to reader) capacity and massive-tag information feedback in IoT scenarios is the main challenge. Compared to conventional UHF RFID backscattering whose data rate is limited within hundreds of kb/s, Ultra-wideband (UWB) transmission have been verified with the performance of Mb/s data rate with several tens of pJ/pulse energy consumption.Therefore, a circuit prototype of UHF/UWB RFID tag replacing UHF backscattering with UWB transmitter is implemented. It also consists of Analog-to-Digital Converter (ADC) and Electrocardiogram (ECG) electrodes for healthcare applications of real-time remote monitoring of multiple patients ECG signals. The ECG electrodes are fabricated on paper substrate by inkjet printing to improve patient comfort. Key contribution of the thesis includes: 1) the power management scheme and circuit design of passive UHF/UWB RFID display tag. The tag sensitivity (the input RF power) is -10.5 dBm for EC display driving, comparable to the performance of conventional passive UHF RFID tags without display functions, and -18.5 dBm for UWB transmission, comparable to the state-of-the-art performance of passive UHF RFID tag. 2) communication flow and circuit design of UHF/UWB RFID tag with ECG sensing. The optimum system throughout is 400 tags/second with 1.5 KHz ECG sampling rate and 10 Mb/s UWB pulse rate. / <p>QC 20151012</p>
179

Nurses' Acceptance of RFID Technology in a Mandatory-Use Environment

Norten, Adam 01 January 2011 (has links)
Radio frequency identification (RFID) technology allows for the scanning of RFID-tagged objects and individuals without line-of-sight requirements. Healthcare organizations use RFID to ensure the health and safety of patients and medical personnel and to uncover inefficiencies in operations. The successful implementation of a system incorporating RFID technologies requires acceptance and use of the technology. Nurses are a group of employees who must use RFID in hospitals throughout the United States. However, due to their being tracked by RFID technology, some of these nurses feel like "big brother" is watching them. This predictive study used a theoretical model that assessed the effect of five independent variables, namely, privacy concerns, attitudes, subjective norms, controllability, and self-efficacy, on a dependent variable, nurses' behavioral intention to use RFID. A total of 106 U.S. registered nurses answered a Web-based questionnaire containing previously validated and adapted questions that were answered through a five-point Likert scale. Two statistical methods, linear regression and multiple linear regression, were used to investigate the survey results. The results of the linear regression analysis showed that privacy concerns, attitudes, subjective norms, and self-efficacy were each a significant predictor of nurses' behavioral intention to use RFID. The results of the multiple linear regression analysis showed that all the constructs together accounted for 60% of the variance in nurses' intention to use RFID. Of the five predictors in the model, attitudes provided the largest unique contribution when the other predictors in the model were held constant. Subject norms also provided a unique contribution. The other predictors in the model (privacy concerns, controllability, and self-efficacy) were not statistically significant and did not provide a significant unique contribution to nurses' behavioral intention to use RFID. The outcomes of this study constitute a significant original contribution to the body of knowledge in the area of information systems by enhancing understanding of the factors affecting RFID acceptance among nurses. The results of this research also provide hospitals and medical centers that require their nurses to use RFID technology with information that they can use to address barriers to their nurses' acceptance and use of RFID technology.
180

Cryptography for Ultra-Low Power Devices

Kaps, Jens-Peter E 04 May 2006 (has links)
Ubiquitous computing describes the notion that computing devices will be everywhere: clothing, walls and floors of buildings, cars, forests, deserts, etc. Ubiquitous computing is becoming a reality: RFIDs are currently being introduced into the supply chain. Wireless distributed sensor networks (WSN) are already being used to monitor wildlife and to track military targets. Many more applications are being envisioned. For most of these applications some level of security is of utmost importance. Common to WSN and RFIDs are their severely limited power resources, which classify them as ultra-low power devices. Early sensor nodes used simple 8-bit microprocessors to implement basic communication, sensing and computing services. Security was an afterthought. The main power consumer is the RF-transceiver, or radio for short. In the past years specialized hardware for low-data rate and low-power radios has been developed. The new bottleneck are security services which employ computationally intensive cryptographic operations. Customized hardware implementations hold the promise of enabling security for severely power constrained devices. Most research groups are concerned with developing secure wireless communication protocols, others with designing efficient software implementations of cryptographic algorithms. There has not been a comprehensive study on hardware implementations of cryptographic algorithms tailored for ultra-low power applications. The goal of this dissertation is to develop a suite of cryptographic functions for authentication, encryption and integrity that is specifically fashioned to the needs of ultra-low power devices. This dissertation gives an introduction to the specific problems that security engineers face when they try to solve the seemingly contradictory challenge of providing lightweight cryptographic services that can perform on ultra-low power devices and shows an overview of our current work and its future direction.

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