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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.
101

Sensor systems for positioning and identification in ubiquitous computing

Jayabharath Kumar, Suri January 2006 (has links)
Technologies for position sensing and identification are important to have in ubiquitous computing environments. These technologies can be used to track users, devices, and artefacts in the physical milieu, for example, locating the position of a cellular phone in av physical environment. The aim of this thesis was to survey and classify available technologies for location sensing and identification. We have made a literature study on both commercial and research-oriented systems and technologies for use in indoor and outdoor environments. We compared the characteristics of the underlying sensing technologies with respect to physical size, sensing method, cost, and accuracy. We conclude the thesis with a set of recommendations to developers and discuss the requirements on future sensing technologies and their use in mobile devices and environments.
102

Inovação tecnológica: um estudo exploratório de adoção do RFID (Identificação por Radiofrequência) e redes de inovação internacional / Technology innovation: the exploratory study of RFID (Radio Frequency Identification) adoption and network of international innovation

Miriam Christi Midori Oishi Nemoto 03 December 2009 (has links)
A inovação é um meio utilizado pelas empresas para se manterem no mercado, crescerem economicamente e gerarem vantagens competitivas. Seja a inovação referente a processo, produto, ou melhorias incrementais ou radicais, é importante estabelecer os fatores que devem ser levados em consideração no processo de adoção. Contudo, os gestores enfrentam dificuldades neste processo, dada a carência de ferramentas ou modelos que possam auxiliálos, oferecendo-lhes uma abordagem sistêmica dos fatores envolvidos. Desse modo, os objetivos desta pesquisa são identificar e analisar: 1) os fatores que devem ser levados em consideração na decisão de adotar-se a tecnologia RFID, Radio Frequency Identification, nas empresas e 2) as barreiras e facilitadores à implantação da tecnologia RFID na manufatura. Descoberta em 1935, pelo físico escocês Robert Alexander Watson-Watt, esta tecnologia foi utilizada inicialmente na Segunda Guerra Mundial para identificação de aviões inimigos. Entretanto, também pode ser empregada para rastreamento na cadeia de suprimentos, monitoramento de pessoas, verificação de autenticidade, identificação de pessoas em áreas de segurança e controle eletrônico, entre outros. O modelo apresenta quatro fatores (ambiente externo, ambiente interno, redes de inovação e tecnologia), todos passíveis de desdobramento em subfatores. Esta pesquisa limitou-se a apenas um grupo de subfatores, tendo partido da revisão bibliográfica sobre inovação tecnológica, adoção de inovação, tecnologia RFID, redes de inovação e manufatura. Na etapa seguinte, foram elaborados um questionário e um roteiro de entrevista para coleta de dados e informações. Para validá-los, foram realizados pré-testes e em seguida as modificações sugeridas pelo teste, chegando-se ao modelo conceitual final. Este foi aplicado com base na metodologia de estudos de casos múltiplos em um grupo de quatro empresas, duas das quais localizadas nos EUA e as demais no Brasil. O estudo demonstrou a utilidade dos modelos na decisão da adoção da tecnologia RFID e para a identificação das barreiras e facilitadores à sua implantação na manufatura. Por se tratar de uma tecnologia nova e dada a escassez de estudos já completados nesta área de gestão, sugere-se pesquisar elementos adicionais aos abordados nesta pesquisa. Estes incluem fatores relativos à especialidade ocupacional do indivíduo que irá operar a tecnologia, perfil, cultura e porte da empresa, influência do processo de comunicação e mensuração do retorno do investimento, bem como nível de centralização e modelo de gestão da empresa, além de outros fatores envolvidos nas redes de inovação, como governança, desenvolvimento de competências, tipo de relacionamento entre os integrantes e a sua influência no processo de internacionalização de empresas. A metodologia adotada não permite a generalização das conclusões. / Innovation is one of the means companies resort to, in order to safeguard their market position, grow financially and gain competitive advantages. Regardless of whether the innovation concerns process, product, and incremental or radical improvements, it is important to establish the factors that must be taken into account in the process of adopting it. Managers, however, have difficulty in this process, because of the lack of tools or models capable of helping them and of providing a systemic approach to the factors involved. Thus, the objectives of this research study are to identify and analyze (1) the factors that must be taken into account when deciding whether to adopt the Radio Frequency Identification (RFID) technology within a firm and (2) the barriers and facilitating elements for the implementation of RFID in manufacturing. Discovered in 1935 by the Scottish physicists Robert Alexander Watson-Watt, this technology was first used during World War II, to identify enemy aircraft. However, it can also be used to track the elements of a supply chain, monitor individuals, verify authenticity, identify people in security areas, or conduct electronic control, among other possibilities. Our model presents four factors (external environment, internal environment, innovation networks and technology), all of which can be broken down into sub-factors. This study focused on one sub-factors group. The research starting point was a bibliographical review of technological innovation, innovation adoption, RFID technology, innovation networks and manufacturing. The next stage consisted of developing a questionnaire and interview guidelines for data and information collection. These tools were then pretested for validation, which led to their adjustment and to the final conceptual model. This was then applied, based on the multiple case studies methodology, to a group of four enterprises, two of which were in the USA and the other in Brazil. The study showed the usefulness of the models for the decision of adopting RFID technology and for the identification of the barriers and facilitators connected with the implementation of RFID in manufacturing. Because it is a new technology, and given the scarcity of completed studies in this management area, we suggest researching other elements besides those addressed in our research, including those that concern the occupational specialization of the individual that will operate the technology, the profile, culture and size of the firm, the influence of the communication process and the return on investment metrics, as well as the enterprises level of centralization and management model, in addition to other factors involved in innovation networks, such as governance, development of competencies, type of relations among the network members and influence on the enterprises internationalization process. The methodology used, however, does not allow one to generalize the studys conclusions.
103

Design of substrate integrated waveguide H-plane horn antenna with symmetric beamwidths

Iqbal, Farzeen 16 August 2017 (has links)
Millimeter-wave Substrate Integrated Waveguide (SIW) technology presents itself as the most viable solution for the development of RF systems. It is a cost-e ective solution, suitable for mass production of such systems. Like planar circuits, SIW structures are compact, light weight and easy to fabricate. They also preserve some of the major advantages of metallic waveguides, namely, low loss, high quality factor and high power handling capabilities. In RF systems, rectangular waveguide horns have found various applications due to their exceptional radiation properties. From their simple construction, ease of ex- citation, usefulness and high gain, they are readily used as feed component in various RF systems, they also aid as the standardization for calibration and gain measure- ments of other high gain antennas. We are aware that, in an H-plane horn antenna, the rectangular waveguide is flared in the direction of the H-field. A large aperture in the H-plane presents the narrower half power beamwidth whereas a small aperture in the E-plane gives a wider beamwidth. In this research, the design of a SIW H- plane horn antenna with approximately symmetric half power beamwidths in both the E- and H-planes is proposed, using the commercially available electromagnetic field solver CST Microwave Studio to design and simulate proposed antenna characteristics and performance. Also, radiation patterns are analyzed and in order to validate the simulation results, measurements are performed on a fabricated prototype antenna. / Graduate
104

A Study of Anti-collision Multi-tag Identification Algorithms for Passive RFID Systems

Kamineni, Neelima 05 1900 (has links)
The major advantages of radio frequency identification (RFID) technology over barcodes are that the RFID-tagged objects do not require to be in line-of-sight with the reader for their identification and multiple objects can be read simultaneously. But when multiple objects are read simultaneously there is always a problem of collision which reduces the efficiency of the system. This thesis presents a comprehensive study of the dynamic framed slotted ALOHA (DFSA)-based anti-collision multi-tag identification algorithms for passive RFID system. Performance of various DFSA algorithms is compared through extensive simulation results. In addition, a number of simple performance improvement techniques have also been investigated in this thesis, including improved estimation techniques for the number of tags in each read cycle and a low-complexity heuristic stopping criterion that can be easily implemented in the practical system.
105

Návrh a realizace UHF RFID tagu pro snímání hladiny kapaliny / Design and realization of a passive UHF RFID liquid level sensor tag

Pařízek, Tomáš January 2018 (has links)
The project deals with a theoretical design of passive ultra-high frequency radio identification (UHF RFID) tag for the measurement of liquid levels. Liquid level has an influence on the input impedance of an RFID tag antenna. The changes of input impedance have been used to distinguish individual liquid levels. Furthermore, this project presents optimization methods for the highest efficiency of an UHF RFID tag in Matlab and it aims to design a suitable antenna within CST MICROWAVE STUDIO.
106

Planární anténní řady pro RFID aplikace / Planar antenna arrays for RFID applications

Pochobradský, Jakub January 2013 (has links)
This thesis describes the basic principles of radio frequency identification, basic characteristics of patch antennas, the possibility of their feeding and design of planar antenna series. Are discussed, impedance matching options. The selected antenna arrays were realised, measuring their parameters was down and measured parameters was compared with simulation results.
107

Implementing tracking and tracing methods for returnable containers / Implementering av spårningsmetoder för återvändningsbara containers

Felix, Ahlström Jönsson January 2019 (has links)
No description available.
108

A Patient Identification System using RFID and IEEE 802.11b Wireless Networks

Aguilar, Antonio January 2007 (has links)
The recent increased focus on patient safety in hospitals has yielded a flood of new technologies and tools seeking to improve the quality of patient care at the point of care. Hospitals are complex institutions by nature, and are constantly challenged to improve the quality of healthcare delivered to patients while trying to reduce the rate of medical errors and improve patient safety. Here a simple mistake such as patient misidentification, specimen misidentification, wrong medication, or wrong blood transfusion can cause the loss of a patient’s life. Misidentification of patients is a common problem that many hospitals face on the daily basis. Patient misidentification is one of the leading causes of medical errors and medical malpractice in hospitals and it has been recognised as a serious risk to patient safety. Recent studies have shown that an increasing number of medical errors are primarily caused by adverse drug events which are caused directly or indirectly by incorrect patient identification. In recognition of the increasing threat to patient safety, it is important for hospitals to prevent these medical errors from happening by adopting a suitable patient identification system that can improve upon current safety procedures. The focus of this master’s thesis is the design, implementation, and evaluation of a handheld-based patient identification system that uses radio frequency identification (RFID) and IEEE 802.11b wireless local area networks to identify patients. In this solution, each patient is given a RFID wristband which contains demographic information (patient ID number, ward number, hospital code, etc.) of the patient. A handheld device equipped with IEEE 802.11b wireless local area network connectivity and a RFID reader is then used by the medical staff to read the patient’s wristband, identify the patient, and access the relevant records of this patient. This work was carried out at the Department of Medical Physics and Bioengineering at the University College Hospital Galway (UCHG), Ireland and the National University of Ireland, Galway. / Ökande de nya fokuserar på patientsäkerhet i sjukhus har givit en översvämning av nya teknologier och bearbetar sökande att förbättra det kvalitets av patient omsorg på peka av omsorg. Sjukhus är komplexa institutions vid naturen och utmanas ständig för att förbättra det kvalitets av sjukvården som levereras till prövas patient för att förminska klassa av medicinska fel och för att förbättra patient säkerhet. Här kan ett enkelt fel liksom patient misidentification, specimenmisidentification, fel läkarbehandling eller fel blodtransfusion orsaka förlusten av ett liv för patient. Misidentification av patient är ett allmänningproblem som många sjukhus vänder mot daglig. Patient misidentification är en av leda orsakar av medicinska fel, och den medicinska malpracticen i sjukhus och den har känts igen som ett allvarligt riskerar till patient säkerhet. Nya studies har visat att ett ökande numrerar av medicinska fel orsakas i första hand av motsatt droghändelser vilka orsakas direkt eller indirekt av oriktigt patient ID. I recognition av den ökande hot till patientsäkerhet är det viktigt att sjukhus förhindrar dessa medicinska fel från att hända, genom att adoptera ett passande patient ID system som kan förbttra på säkerhetsrutin. Fokusera av denna avhandling är designen, genomförande, och utvärderingen av ett patient IDsystem, som använder radiofrekvensidentifiering (RFID) och radion 802.11b, knyter kontakt för att identifiera patient. I denna lösning ges varje patient ett RFID-armband som innehåller demografikinformation (den patient personnumer, avdelning kod, sjukhuset kod, osv.) av patient. En handdator, som utrustas med trådlös IEEE 802.11b och en RFIDs ändare/mottagare, används därefter av den medicinska personal för att läsa armbandet för patient och för att identifiera patient. Detta arbete bars ut på avdelningen av medicinskfysik och bioteknik på Universitetssjukhuset Galway (UCHG), Irland och den Nationella Universitet av Irland, Galway.
109

Design of an Ultra-wideband Radio Frequency Identification System with Chipless Transponders

Barahona Medina, Marvin Renan 17 September 2019 (has links)
The state-of-the-art commercially available radio-frequency identification (RFID) transponders are usually composed of an antenna and an application specific integrated circuit chip, which still makes them very costly compared to the well-established barcode technology. Therefore, a novel low-cost RFID system solution based on passive chipless RFID transponders manufactured using conductive strips on flexible substrates is proposed in this work. The chipless RFID transponders follow a specific structure design, which aim is to modify the shape of the impinged electromagnetic wave to embed anidentification code in it and then backscatter the encoded signal to the reader. This dissertation comprises a multidisciplinary research encompassing the design of low-cost chipless RFID transponders with a novel frequency coding technique, unlike usually disregarded in literature, this approach considers the communication channel effects and assigns a unique frequency response to each transponder. Hence, the identification codes are different enough, to reduce the detection error and improve their automatic recognition by the reader while working under normal conditions. The chipless RFID transponders are manufactured using different materials and state-of-the-art mass production fabrication processes, like printed electronics. Moreover, two different reader front-ends working in the ultra-wideband (UWB) frequency range are used to interrogate the chipless RFID transponders. The first one is built using high-performance off-theshelf components following the stepped frequency modulation (SFM) radar principle, and the second one is a commercially available impulse radio (IR) radar. Finally, the two readers are programmed with algorithms based on the conventional minimum distance and maximum likelihood detection techniques, considering the whole transponder radio frequency (RF) response, instead of following the commonly used approach of focusing on specific parts of the spectrum to detect dips or peaks. The programmed readers automatically identify when a chipless RFID transponder is placed within their interrogation zones and proceed to the successful recognition of its embedded identification code. Accomplishing in this way, two novel fully automatic SFM- and IRRFID readers for chipless transponders. The SFM-RFID system is capable to successfully decode up to eight different chipless RFID transponders placed sequentially at a maximum reading range of 36 cm. The IR-RFID system up to four sequentially and two simultaneously placed different chipless RFID transponders within a 50 cm range.:Acknowledgments Abstract Kurzfassung Table of Contents Index of Figures Index of Tables Index of Abbreviations Index of Symbols 1 Introduction 1.1 Motivation 1.2 Scope of Application 1.3 Objectives and Structure Fundamentals of the RFID Technology 2.1 Automatic Identification Systems Background 2.1.1 Barcode Technology 2.1.2 Optical Character Recognition 2.1.3 Biometric Procedures 2.1.4 Smart Cards 2.1.5 RFID Systems 2.2 RFID System Principle 2.2.1 RFID Features 2.3 RFID with Chipless Transponders 2.3.1 Time Domain Encoding 2.3.2 Frequency Domain Encoding 2.4 Summary Manufacturing Technologies 3.1 Organic and Printed Electronics 3.1.1 Substrates 3.1.2 Organic Inks 3.1.3 Screen Printing 3.1.4 Flexography 3.2 The Printing Process 3.3 A Fabrication Alternative with Aluminum or Copper Strips 3.4 Fabrication Technologies for Chipless RFID Transponders 3.5 Summary UWB Chipless RFID Transponder Design 4.1 Scattering Theory 4.1.1 Radar Cross-Section Definition 4.1.2 Radar Absorbing Material’s Principle 4.1.3 Dielectric Multilayers Wave Matrix Analysis 4.1.4 Frequency Selective Surfaces 4.2 Double-Dipoles UWB Chipless RFID Transponder 4.2.1 An Infinite Double-Dipole Array 4.2.2 Double-Dipoles UWB Chipless Transponder Design 4.2.3 Prototype Fabrication 4.3 UWB Chipless RFID Transponder with Concentric Circles 4.3.1 Concentric Circles UWB Chipless Transponder 4.3.2 Concentric Rings UWB Chipless RFID Transponder 4.4 Concentric Octagons UWB Chipless Transponders 4.4.1 Concentric Octagons UWB Chipless Transponder Design 1 4.4.2 Concentric Octagons UWB Chipless Transponder Design 2 4.5 Summary 5. RFID Readers for Chipless Transponders 5.1 Background 5.1.1 The Radar Range Equation 5.1.2 Range Resolution 5.1.3 Frequency Band Selection 5.2 Frequency Domain Reader Test System 5.2.1 Stepped Frequency Waveforms 5.2.2 Reader Architecture 5.2.3 Test System Results 5.3 Time Domain Reader 5.3.1 Novelda Radar 5.3.2 Test System Results 5.4 Summary Detection of UWB Chipless RFID Transponders 6.1 Background 6.2 The Communication Channel 6.2.1 AWGN Channel Modeling and Detection 6.2.2 Free-Space Path Loss Modeling and Normalization 6.3 Detection and Decoding of Chipless RFID Transponders 6.3.1 Minimum Distance Detector 6.3.2 Maximum Likelihood Detector 6.3.3 Correlator Detector 6.3.4 Test Results 6.4 Simultaneous Detection of Multiple UWB Chipless Transponders 6.5 Summary System Implementation 7.1 SFM-UWB RFID System with CR-Chipless Transponders 7.2 IR-UWB RFID System with COD1-Chipless Transponders 7.3 Summary Conclusion and Outlook References Publications Appendix A RCS Calculation Measurement Setups Appendix B Resistance and Skin Depth Calculation Appendix C List of Videos Test Videos Consortium Videos Curriculum Vitae
110

[en] RFID TECHNOLOGY APPLIED TO LOGISTICS / [pt] TECNOLOGIA RFID APLICADA À LOGÍSTICA

CICERO CASEMIRO DA COSTA NOGUEIRA FILHO 03 January 2006 (has links)
[pt] A crescente competitividade entre cadeias de suprimentos, proveniente de um cenário globalizado onde o mercado exige um forte desempenho das cadeias produtivas e flexibilidade com relação à qualidade, prazos e custos dos produtos, acentua a importância da participação da logística como um agente fomentador de inteligência estratégica entre as diversas disciplinas dos processos industriais. A necessidade de obtenção e gerenciamento de um fluxo ideal de informações e ações dentro dos atuais processos produtivos de uma SC - Supply Chain (cadeia de suprimentos) para responder de forma competitiva e segura às demandas vindas deste mercado, aliada ao desenvolvimento nos últimos anos da tecnologia sem fio (wireless) Radio Frequency Identification (Identificação por Rádio Freqüência), abre grandes oportunidades à aplicação do RFID na logística. Neste trabalho pretendeu-se dar continuidade ao trabalho intitulado Aplicações de tecnologias sem fio em operações logísticas, divulgado em Figueiredo (2004). Assim, de forma a complementar o trabalho de Figueiredo (2004), o propósito desta dissertação é dar maior visibilidade sobre o uso da tecnologia de RFID com aplicação voltada a processos logísticos, de forma a promover maior compreensão dos impactos desta tecnologia nas diversas aplicações industriais. Para tal, o presente trabalho analisa diversos estudos de casos reais abrangendo empresas que utilizam esta tecnologia, ou que estão em fase piloto de sua utilização no Brasil. Com base nos resultados de estudos de casos realizados pelo autor, puderam ser analisados alguns impactos nos usos e oportunidades do RFID nos processos logísticos. / [en] The growing competitiveness among supply chains, originated from a global scenery where the market demands a strong performance and flexibility regarding quality, periods and costs of the products from the productive chains, emphasizes the importance of the logistic participation as a promoting agent of strategic intelligence among the several disciplines of the industrial processes. The necessity of obtaining an efficient management system of information flow and actions inside the current productive processes of a SC - (Supply Chain) to answer in a safe and competitive way to the demands coming from this market, allied with the development of the wireless technology opens great opportunities to apply RFID (Radio Frequency Identification) technology to logistics. This work intends to continue the research conducted in Figueiredo (2004) entitled Aplicações de tecnologias sem fio em operações logísticas. Therefore, the main goal of this master dissertation is to give more visibility concerning the use of the RFID technology applied to logistic processes in a way to promote a better comprehension of the impacts of this technology in different industrial applications. In order to achieve its goal, this dissertation analyses different case studies with companies that use this technology or are in pilot phase of its use in Brazil. Regarding the results of case studies conducted by the author it was possible to analyze some impacts in the uses and opportunities of RFID in the logistics processes.

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