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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.
181

Systemization of RFID Tag Antenna Design Based on Optimization Techniques and Impedance Matching Charts

Butt, Munam 16 July 2012 (has links)
The performance of commercial Radio Frequency Identification (RFID) tags is primarily limited by present techniques used for tag antenna design. Currently, industry techniques rely on identifying the RFID tag application (books, clothing, etc.) and then building antenna prototypes of different configurations in order to satisfy minimum read range requirements. However, these techniques inherently lack an electromagnetic basis and are unable to provide a low cost solution to the tag antenna design process. RFID tag performance characteristics (read-range, chip-antenna impedance matching, surrounding environment) can be very complex, and a thorough understanding of the RFID tag antenna design may be gained through an electromagnetic approach in order to reduce the tag antenna size and the overall cost of the RFID system. The research presented in this thesis addresses RFID tag antenna design process for passive RFID tags. With the growing number of applications (inventory, supply-chain, pharmaceuticals, etc), the proposed RFID antenna design process demonstrates procedures to design tag antennas for such applications. Electrical/geometrical properties of the antennas designed were investigated with the help of computer electromagnetic simulations in order to achieve optimal tag performance criteria such as read range, chip-impedance matching, antenna efficiency, etc. Experimental results were performed on the proposed antenna designs to compliment computer simulations and analytical modelling.
182

Design Of A Radio Frequency Identification (rfid) Antenna

Kalayci, Sefa 01 May 2009 (has links) (PDF)
Fundamental features of Radio Frequency Identification (RFID) systems used in different application areas will be reviewed. Techniques used in realizing RFID antenna systems will be studied and the procedure to realize a specific RFID antenna type possessing desired characteristics will be described. Electrical properties such as radiation pattern, impedance will be predicted using analytical and/or computer simulation techniques. Experimental investigations will be carried out to complement the theoretical work.
183

Balises pour l’intervention avec les technologies auprès des élèves qui ont des incapacités intellectuelles

Chalghoumi, Hajer 07 1900 (has links)
Considérées comme des moyens incontournables de participation à la société, les technologies de l’information et de la communication (TIC) constituent une piste de solution prometteuse pour l’enseignement et l’apprentissage auprès des élèves qui ont des incapacités intellectuelles. Toutefois, plusieurs auteurs dénoncent la faible utilisation des TIC en éducation de ces élèves. Pire encore, les recherches sur le sujet génèrent des résultats intéressants, mais d’une contribution limitée pour l’avancement des connaissances dans le domaine. Guidées par l’intuition et par un enthousiasme empirique évident, ces recherches s’appuient rarement sur des cadres de référence. Certes la documentation scientifique foisonne de champs de savoirs qui peuvent contribuer à ce domaine, mais ces contributions sont parcellaires et peu adaptées aux spécificités de ce dernier. L’intervention avec les TIC auprès des élèves qui ont des incapacités intellectuelles demeure donc un champ conceptuel mal défini qui n'est légitimé par aucun cadre de référence en particulier. Cette recherche doctorale se situe en phase de préconception d’un modèle de l’intervention avec les TIC auprès des élèves qui ont des incapacités intellectuelles. Elle vise à mettre en place des balises solides pouvant servir de cadre à l’élaboration d’un modèle de cette intervention. Dans cette phase de préconception, nous poursuivons deux objectifs, à savoir : 1) la mise au point d’un référentiel qui constitue un cadre intégrateur des connaissances existantes en la matière, qui servira avant tout à structurer et à organiser les informations disponibles à l’intérieur d’une synthèse validée par des experts et des intervenants oeuvrant auprès de ce type d’élèves et 2) l’élaboration d’un cahier des charges fonctionnel qui s’appuie sur le référentiel développé et qui précise les fonctions qu’un modèle idéal de l’intervention avec les TIC auprès des élèves qui ont des incapacités intellectuelles devrait remplir pour répondre pleinement aux besoins de ses différents utilisateurs. Ces balises (le référentiel et le cahier des charges fonctionnel) sont destinées, principalement, à des chercheurs, des concepteurs de technologies, des formateurs d’enseignants, etc. Les élèves, les enseignants et autres agents de l'éducation pourront en bénéficier indirectement à travers les applications dérivées de ces balises (programmes de formation, technologies, recherches, scénarios pédagogiques, etc.). / Regarded as essential means of participation in society, information and communication technologies (ICT) are a promising track for teaching and learning of students with intellectual disabilities. However, several authors denounce the low use of ICT in education of these students. Worse yet, research on the subject generate interesting results, but a limited support to contribute to the advancement of knowledge in the field. Guided by intuition and empirical enthusiasm, theses researches often rely on reference frames. While the literature abounds with fields of knowledge that can contribute to this area, these proposals are fragmented and poorly adapted to the specifics of the latter. The educational intervention with ICT with students with intellectual disabilities remains an ill-defined conceptual field that is not legitimized by any particular reference frame. This doctoral research precedes the conception of an educational intervention model using ICT with students who have intellectual disabilities. It aims to establish strong tags that can serve as a framework for developing this model. In this phase of preconception, we pursue two objectives: 1) developing a repository consisting in a framework for integrating existing knowledge on the subject that will serve primarily to structure and organize the information available within the a synthesis validated by experts and practitioners; 2) developing a tender specification of the functions that a perfect model of this intervention should meet to fully satisfy the needs of different users. These tags (the repository and the tender specification) are intended, mainly, to researchers, technology developers, teacher educator, etc. Students, teachers and other educational agents will benefit indirectly from these tags through their applications by the first users of (training programs, technologies, studies, lesson plans, etc.).
184

RFID in Virtuellen Unternehmen: Potenziale von Data-on-Tag

Werner, Kerstin, Grummt, Eberhard 23 April 2014 (has links) (PDF)
No description available.
185

Aspectos de crescimento e mortalidade do guanhumi (CARDISOMA GUANHUMI) em um manguezal de acesso restrito na Ilha de Itamaracá – PE

COSTA, Denise Fabiana de Moraes 19 August 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-02-20T13:51:05Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação CD Biblioetca Denise Moraes 2016 FINAL.pdf: 2561125 bytes, checksum: 30370d4b25d98afe00850c78927ba185 (MD5) / Made available in DSpace on 2017-02-20T13:51:05Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação CD Biblioetca Denise Moraes 2016 FINAL.pdf: 2561125 bytes, checksum: 30370d4b25d98afe00850c78927ba185 (MD5) Previous issue date: 2016-08-19 / FACEPE / O conhecimento dos parâmetros de crescimento e mortalidade em braquiúros é fundamental para a compreensão da sua dinâmica e para o manejo de suas populações. Neste sentido, foram estimados os parâmetros de crescimento e mortalidade para Cardisoma guanhumi Latreille, 1825 (guaiamum), uma espécie com elevada importância socioeconômica no nordeste brasileiro e atualmente considerada pelo Ministério do Meio Ambiente como Criticamente em Perigo de extinção. As amostragens foram efetuadas durante um ano, entre abril de 2015 a março de 2016, na margem superior do mangue do CMA/ICMBio/CEPENE na ilha de Itamaracá, Pernambuco, Brasil. Foram capturados, medidos e pesados 1078 indivíduos (572 machos e 506 fêmeas). Destes, 291 indivíduos foram marcados com microchips PIT ("Passive Integrated Transponder"), para determinação dos parâmetros de crescimento através dos incrementos de peso e tamanho e do crescimento individual. Para a análise dos dados, foram utilizados o método ELEFAN I (baseado na distribuição de frequência de largura de carapaça de 1078 indivíduos), inserido no pacote computacional Fisat II e através da função GrowthTraject (baseada em incrementos individuais de 291 indivíduos marcados com PITs, utilizando o pacote fishmethods (Ambiente de programação “R”). Os indivíduos de C.guanhumi apresentaram largura da carapaça entre 20,9 e 70,0 mm (média: 43,45 mm, desvio padrão: 8,53 mm, mediana: 44,05 mm) o peso total entre 4 e 162 g (média: 45,85 g, desvio padrão: 25,34 g, mediana: 44,0 g). Não houve diferenças significativas, em tamanho médio e peso médio, entre machos e fêmeas. Os parâmetros de crescimento estimados com a função GrowthTraject para 130 incrementos (machos e fêmeas) foram: Linf (tamanho assintótico) = 108,03 mm (largura da carapaça); K (coeficiente de crescimento) = 0,145 ano-1. A Mortalidade total (Z) da população, estimada pelo método Length – converted Catch Curve (pacote FISAT II) usando os parâmetros de crescimento do GrowthTraject foi de = 2,39 ano-1. Não ocorrem capturas comerciais nesta área fechada, portanto, este valor equivale à mortalidade total e natural (Z=M). A idade dos indivíduos capturados variou de 1,49 anos (20,9mm) a 7,02 anos (70,0mm). O recrutamento, calculado no pacote FISAT II e estimado através da presença de juvenis, mostrou-se contínuo durante todo o ano. Os métodos de análises de frequência e comprimento inseridos no pacote FISAT (Bhattacharya, ELEFAN I e Shepherd’s) não foram capazes de determinar os parâmetros de crescimento, provavelmente devido ao crescimento lento e recrutamento contínuo durante todo ano. O tamanho total da população no manguezal do CMA foi estimado em 1262 indivíduos (+- 401ind.), baseado nos dados de marcação e recaptura. / Knowledge on the growth parameters and mortality in brachyuran is fundamental to the understanding of the dynamics and management of their populations. Growth and mortality parameters were estimated for Cardisoma guanhumi Latreille, 1825 (locally known as”guaiamum”), a species with high socio-economic importance in northeastern Brazil and currently considered by the Ministry of the Environment as Critically Endangered of Extinction. The samples were taken over one year, from April 2015 to March 2016, at the upper margin of a small, isolated mangrove patch at CMA-ICMBio-CEPENE on Itamaracá Island, Pernambuco, Brazil. A total of 1078 individuals (572 males and 506 females) were captured, measured and weighed. Of these, 291 individuals were marked with PIT tags (Passive Integrated Transponder tags), as to determine the growth parameters through the analysis of the increments in weight and size and individual growth. For the data analysis, we used the ELEFAN I method (based on the frequency distribution of carapace width 1078 individuals), inserted into the computer package FISAT II and through the GrowthTraject function (based on individual increments of 291 individuals marked with PIT tags, using the fishmethods package ("R” Environment). C. guanhumi showed carapace widths between 20.9 and 70.0 mm (mean: 43,45 mm, standard deviation: 8,53 mm, median: 44,05 mm) and total weight between 4 and 162 g (mean: 45,85 g, standard deviation: 25,34 g, median: 44,0 g). There were no significant differences in average size and average weight between males and females. Growth parameters estimated with the fishmethods package, based on 130 increments (males and females), were: L∞ (asymptotic carapace width) = 108.03 mm; K (coefficient growth) = 0.145 y-1. Total mortality (Z) of the population, estimated through the Length-converted catch Curve method (FISAT II package), using the fishmethods growth parameters, was 2.39 y-1. Since this is a restricted area without regular commercial catches, so this value is roughly equivalent to the total and natural mortality (Z = M). The age of the individuals captured ranged from 1.49 years (20,9 mm) to 7.02 years (70,0 mm). Recruitment, calculated in FISAT II package and estimated by the presence of juveniles, showed to be continuous throughout the year. The methods of length-frequency analysis inserted in the FISAT package (Bhattachary of protective measures for this species.
186

Near Field Communication : En studie om NFC-teknikens möjliga användningsområden och utveckling inom sociala medier / Near Field Communication : A study on the NFC technology’s possible field of application and its development within social media

Hamberg, Lisa, Huber, Christine January 2014 (has links)
In this report we examine the NFC (Near Field Communication) technology as far as the development has come until today. We adress different use areas and explain the technical funcionality. By using data collection methods as a specialist interview and also a survery we want to detect potential risks and safety-issues in implementation of the new technology. Our main-focus in this report is to examine how NFC can play an important role in the developement of social interaction and social media. By compiling our data and research materials we will analyze and present a report conslusion. In our conclusion we will introduce our thoughts about the technology as NFC gets more and more common in our physical lives and also propose further research-areas. We will share potential risks about the technology as it is developing to alert future researchers and developers, but also pay attention to the opportunities the technology may bring. / Med vår studie har vi valt att undersöka tekniken NFC (eng. Near Field Communication) så långt som utvecklingen har kommit i dagsläget. Vi redogör kring vad det finns för olika användningsområden och hur NFC fungerar ur ett tekniskt perspektiv. Genom att intervjua en person som arbetar nära tekniken samt utföra en enkätundersökning vill vi upptäcka potentiella säkerhetsrisker som medföljer implementeringen av tekniken. Studiens huvudfokus är att undersöka hur och om NFC kan ha en viktig roll i utvecklingen och framtiden för sociala medier och interaktion. Med den data vi samlar in under studiens gång kommer vi analysera, diskutera och komma fram till en slutsats. Vi kommer att delge våra tankar kring teknologin då den blir mer och mer vanlig i våra fysiska liv och föreslå vidare forskningsområden. Vi vill uppmärksamma framtida forskare och utvecklare av NFC om potentiella risker som tekniken medför, men också de möjligheter som tekniken öppnar upp.
187

Systemization of RFID Tag Antenna Design Based on Optimization Techniques and Impedance Matching Charts

Butt, Munam January 2012 (has links)
The performance of commercial Radio Frequency Identification (RFID) tags is primarily limited by present techniques used for tag antenna design. Currently, industry techniques rely on identifying the RFID tag application (books, clothing, etc.) and then building antenna prototypes of different configurations in order to satisfy minimum read range requirements. However, these techniques inherently lack an electromagnetic basis and are unable to provide a low cost solution to the tag antenna design process. RFID tag performance characteristics (read-range, chip-antenna impedance matching, surrounding environment) can be very complex, and a thorough understanding of the RFID tag antenna design may be gained through an electromagnetic approach in order to reduce the tag antenna size and the overall cost of the RFID system. The research presented in this thesis addresses RFID tag antenna design process for passive RFID tags. With the growing number of applications (inventory, supply-chain, pharmaceuticals, etc), the proposed RFID antenna design process demonstrates procedures to design tag antennas for such applications. Electrical/geometrical properties of the antennas designed were investigated with the help of computer electromagnetic simulations in order to achieve optimal tag performance criteria such as read range, chip-impedance matching, antenna efficiency, etc. Experimental results were performed on the proposed antenna designs to compliment computer simulations and analytical modelling.
188

Zpracování signálu UHF RFID čtečky / Signal Processing for UHF RFID Reader

Novotný, Jan January 2015 (has links)
The master’s thesis is focused on the UHF RFID reader EXIN-1 signal processing. The first part describes the concept of the EXIN-1 front end, its basic testing and possible communication interfaces for reader control and for receiving and transmitting baseband signals. The second part of this work is aimed to a simple description of EPCglobal Class-1 Generation-2 UHF RFID Protocol, especially to used modulations and codings. In the last part, a block connection between the front end and an ARM Cortex-M4 microcontroller discovery board is designed. The microcontroller is used for generating of all required signals and also for receiving incoming signals and processing them for identification numbers of RFID cards (tags), which are in the reading range of the reader. A decoding algorithm is designed in MATLAB software and implemented to the selected microcontroller. Obtained identification data are displayed on an LCD display and also sent to a PC through a serial communication.
189

RFID in Virtuellen Unternehmen: Potenziale von Data-on-Tag

Werner, Kerstin, Grummt, Eberhard January 2007 (has links)
No description available.
190

Split Intein Applications for Downstream Purification and Protein Conjugation

Galiardi, Jackelyn 05 October 2021 (has links)
No description available.

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