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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.
271

Supply chain visibility and sustainable competitive advantage : an integrated model

Nassar, Shereen January 2011 (has links)
Lack of visibility of the assets in a product supply chain compromises attempts to optimise supply chain management. Increasing the visibility of these assets presents a relatively unexplored frontier in operations and supply where organisations can create competitive advantage through the opportunities asset visibility offer. This research aims at investigating the key capabilities of asset visibility specifically those associated with returnable transport assets that travel across supply chains carrying material and products e.g. cages, boxes, trays, trolleys and pallet bins. In addition, how these capabilities may influence supply chain visibility and firm performance in a way that might lead to sustainable competitive advantage is examined. To achieve these objectives, the research develops a two-stage model that is theoretically grounded in the extended resource-based view. Philosophically, the research adopts a critical realist approach using abductive logic. Methodologically, a sequential exploratory strategy for data collection is implemented. A qualitative, indepth site-based case study supported by field expert interviews was conducted as a pilot study. The pilot study findings refined the initial conceptual model derived from literature and informed the next stage of the research. The quantitative phase focused on refining the factors constituting asset visibility capabilities and then testing the relationship between these capabilities and supply chain visibility, performance and sustainable competitive advantage. Key findings are that asset visibility capabilities are shaped through three key capabilities: (1) an asset management capability formed by both core technological aspects related to tracking and tracing technology, and non-technological ones focusing on logistic-related capability; (2) a complementary technological capability comprising of IT infrastructure for supply chain integration; and (3) a complementary nontechnological capability represented through three sub-capabilities: (a) supply chain process integration; (b) focal firm-3PL relational orientation; and (c) internal firm integration. The research findings prove a positive relationship between asset visibility capabilities and supply chain visibility. In addition, a positive relationship between these capabilities and sustainable competitive advantage through the mediated effect of supply chain visibility and firm performance, is confirmed.
272

Transferência de propriedade de etiquetas RFID e utilização de matrizes MDS 16 X 16 na cifra de bloco AES

Abrahão, Elcio 19 March 2007 (has links)
Made available in DSpace on 2015-02-04T21:45:26Z (GMT). No. of bitstreams: 1 Elcio Abrahao.pdf: 1127215 bytes, checksum: 685b20475f874a3f691c04eb7233574e (MD5) Previous issue date: 2007-03-19 / Neste trabalho foram desenvolvidas duas frentes de pesquisa. Na primeira foram estudados protocolos de comunicação para etiquetas identificadas por rádio freqüência (RFID). As também chamadas etiquetas inteligentes são capazes de armazenar informações e fazer algumas operações computacionais elementares. Estas informações podem ser lidas através de um aparelho leitor sem necessidade de contato físico ou visada, como nas etiquetas de código de barras. A comunicação é feita remotamente por rádio freqüência e esta característica permite que a etiqueta seja suscetível a uma série de ataques que tentam fraudar ou obter informações do usuário sem sua autorização. Um ponto importante na utilização dessas etiquetas é a transferência de propriedade de um usúario para outro. A fim de garantir a segurança e privacidade do usuário nesse momento foi desenvolvida uma nova funcionalidade emum protocolo já existente de comunicação entre etiqueta e leitor a fim de permitir que a etiqueta fosse transferida de dono sem riscos à segurança e à privacidade. O protocolo modificado foi chamado ROTEP. Na segunda frente de pesquisa foi proposta uma nova e mais rápida camada de difusão para a cifra de bloco AES. Essa nova camada substitui as camadas de rotação de bytes e transformação linear sobre colunas por uma nova matriz MDS e involutória. O objetivo é prover difusão completa em uma única iteração, melhorando significativamente a segurança da cifra. Os elementos da nova matriz MDS possuem baixo peso Hamming para proporcionar boa performance tanto na operação de ciframento quanto na de deciframento. Foi utilizada uma matriz de Cauchy ao invés de uma construção circular como na matriz original do AES, pois uma matriz circular não pode ser ao mesmo tempo MDS e involutória. O algoritmo modificado foi chamado MDS-AES.
273

Taggade bibliotek : en studie av adoptionen av RFID på svenska folkbibliotek / Chipped libraries : a study of the Swedish public libraries adoption of RFID

Anteskog, Marit, Nilsson, Maria January 2011 (has links)
The purpose of our research was to examine whether the acceptance and diffusion of RFID technology among the employees at public libraries in Sweden, follow the classic diffusion of innovation model. RFID or Radio Frequency Identification, is a technology that uses radio frequency and microchip technology to track items, in our case, library books and other library materials. Diffusion is the process by which, in our case, the RFID technology is adopted by the library staff. The purpose of this study was to examine what factors influenced the acceptance and adoption of RFID among the library staff. We used Everett Rogers' Diffusion of innovation theory as our framework. According to this theory, there are a multitude of keyfactors, such as relative advantages, compatability, trialability, and observability which interact and influence the acceptance of new technology. For the purpose of this study we formulated a set of hypotheses, and to test them we conducted a nationwide quantitative survey. We used a questionnaire as our data collection instrument. The questionnaire was sent to the top-level employees (head librarian or equivalent) at all the Swedish public libraries. We used x^2 statistic test to analyze the data from our questionnaire survey. The findings show that the adoption of the RFID technology in Swedish Public libraries is in accordance with Rogers' theory of diffusion, and that the attributes which determined the rate of adoption of RFID were: relative advantage (RFID will cause perceived improvements for employees as well as for patrons), compatibility (RFID is consistent with needs), complexity (level of difficulty to use RFID), trialability (RFID may be tried and used), observability (the results of RFID is visible to others). The findings also show that RFID technology was adopted faster when they have financial resources, time and interest in RFID in general, if the library was located in regions with at least 25.000 inhabitants, and in public libraries with at least 10 employees. / Program: Bibliotekarie
274

NFC i kollektivtrafiken : ur kundens perspektiv / NFC in the public transport : from a customer’s perspective

Cheung, Iris, Johansson, Elin, Malaty, Marina January 2013 (has links)
Near Field Communication (NFC) är ett relativt nytt begrepp som har blivit mycket aktuellt under de senaste åren. NFC bygger på en redan befintlig teknik, som kallas Radio Frequency Identification (RFID), som är en teknik som har till uppgift att läsa information på avstånd med hjälp av radiovågor. NFC används redan flitigt i Japan, men har ännu inte riktigt slagit igenom i västvärlden. Det finns dock en del företag som anammat tekniken, då de använder den som exempelvis passerkort. Exempel på företag som använder sig av NFC i Sverige idag är ”ICA to go” och ”SAS”. Kollektivtrafiken använder sig i dagsläget av RFID vid betalning på bussar och spårvagnar. Det innebär att de kort som man stämplar på buss/spårvagn skickar radiovågar mellan kortet och den läsare som finns ombord på fordonet. Vår studie fokuserar på NFC i kollektivtrafiken, där vi har använt Västtrafik som studieobjekt genom hela studien. Fokus ligger på att undersöka kundnöjdheten kring om NFC skulle införas som ett betalningssystem hos kollektivtrafiken och vilka effekter det skulle kunna bli av ett införande. Ett annat fokusområde är kundnöjdheten vid betalning i dagsläget samt att använda NFC som ett betalningssätt. Det finns både positiva och negativa aspekter med den nya tekniken. Vi har i studien gjort en enkätundersökning för att ta reda på hur kunder ser på Västtrafiks betalningssätt i dagsläget. Frågor som ställdes handlade även om vad de tycker om att införa NFC på bussar och spårvagnar. Resultatet från enkätundersökningen har hjälpt oss att svara på frågeställningen som handlar om kundnöjdheten vid införandet av NFC hos kollektivtrafiken. För att komma fram till en relevant slutsats har, förutom enkätundersökning, tidigare forskning om NFC studerats. Det har legat stor vikt vid hur tekniken fungerar och i analysen har vi jämfört de olika betalningssätten med varandra och dragit paralleller med NFC-tekniken. Även hypotesprövningar har gjorts och analyserats kring ämnet. Studien visar att kunder är positiva till införandet av NFC som ett kompletterande betalningsalternativ. Detta leder i sin tur till en ökad kundnöjdhet i kollektivtrafiken, på grund av att kunder inte behöver registrera sig på någon hemsida för att köpa en biljett. Dessutom blir de heller inte beroende av något försäljningsställe för att ladda på sina buss- och spårvagnskort. / Program: Kandidatutbildning i informatik
275

Utvärdering av övervakningsapplikationen DMCG i SL Access / Evaluation of monitor software DMCG in SL Access

Fai Yu, Chuen January 2011 (has links)
Syftet med detta examensarbete ”Utvärdering av övervakningsapplikation DMCG i SL Access” är att vara ett underlag för en ny version av programmet. En kartläggning av applikationens uppbyggnad, funktionalitet och gränssnitt gjordes. Synpunkter och förslag från operatörer som använder programmet samlades in och sammanfattas i rapporten.Den nuvarande versionen av programmet har ett antal brister i de tre områdena. Detta presenteras i examensarbetet så att SL kan använda detta för att skriva ett ändringsförslag till leverantören ERG. Flödet för larm från fo-enheterna visas i en schematisk bild. Ett förslag på förändrad uppbyggnad av larmfunktionalitet, övriga funktioner samt gränssnittet presenteras.DMCG är ett verktyg som kommer att användas av personal som övervakar fo-enheterna, Bärbar biljettmaskin, Biljettmaskin (TP5000, bussvarianten och ombudsvarianten), Kortläsaren (CP5000), SL Access biljettautomat samt automatspärrar. Totalt är det över 2000 enheter som skall övervakas. SL Access är tänkt att leva i minst 15 år och mängden enheter medför att existerande funktionalitet behövs ses över för att verktyget blir så optimerat så möjligt.
276

Electromagnetic applications of graphene and graphene oxide

Huang, Xianjun January 2016 (has links)
Since the isolation of graphene in 2004, a large amount of research has been directed at 2D materials and their applications due to their unique characteristics. This thesis delivers pioneering developments on the applications of graphene and graphene oxide (GO) on electromagnetic ranges such as radio frequency, microwave frequency and THz bands, and specifically 2D materials based antennas, absorbers, sensors and etc. This thesis focuses on exploring electromagnetic applications of monolayer graphene, printed graphene and graphene oxide. In study of monolayer graphene applications, the theoretical and simulation studies are carried out to design tunable terahertz (THz) absorbers, tunable microwave wideband absorbers, and reconfigurable antennas, etc. These studies on the applications of monolayer graphene have proved prospective potentials of graphene in THz sensing, RCS reduction, and reconfigurable antennas. This thesis also presents pioneering advances on electromagnetic applications of printed graphene. Among these works, low-cost highly conductive and mechanically flexible printed graphene is developed for radio frequency (RF) applications. For the first time, effective RF radiation of printed graphene is experimentally demonstrated. Based on these results, applications of printed graphene including RFID (radio frequency identification) tags, anti-tampering RFID, EMI shielding, flexible microwave components such as transmission lines, resonators and antennas, conformable wideband radar absorbers, graphene oxide based wireless sensors, etc. are developed and experimentally demonstrated. This work significantly expands applications of graphene in electromagnetic areas.
277

Identificação por radiofrequência utilizando dispositivos a ondas acústicas de superfície

Müller Vasconcelos, Henrique 31 January 2011 (has links)
Made available in DSpace on 2014-06-12T17:36:57Z (GMT). No. of bitstreams: 2 arquivo3177_1.pdf: 4287717 bytes, checksum: d34811126b89d5ea35c22cacdd5f9194 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / FUNDAÇÃO DE APOIO AO DESENVOLVIMENTO DA UFPE / Nesta dissertação é apresentado um estudo sobre o projeto dos elementos que compõem a etiqueta a ondas acústicas de superfície (OAS) para identificação por radiofrequência (RFID). Também foram desenvolvidas as etapas de processos de microfabricação necessárias e a metodologia para caracterização utilizando impedancímetro, analisador de rede e analisador de espectro. Identificação por radiofrequência é uma tecnologia baseada na leitura de dispositivos, normalmente cliamados de etiquetas, utilizando ondas de radiofrequência. O sistema RPID é constituído basicamente por um conjunto de etiquetas e por uma ou mais unidades de leitura. Cada etiqueta é responsável por carregar um código único de identificação. Por utilizar ondas de rádio, o mecanismo de leitura dispensa a necessidade de um contato visual livre de obstáculos entre o leitor e a etiqueta como ocorre no caso óptico. Essencialmente, a etiqueta RFID OAS funciona como uma linha de retardo, refletindo parcialmente o sinal enviado pelo interrogador. A identidade retorna na forma de um padrão de ecos seguindo um método de codificação baseado na disposição de estruturas metálicas refletoras de ondas acústicas sobre a superfície de um substrato piezoelétrico. Por fim, uma discussão sobre a integração das etiquetas e interrogadores em redes de sensores, seja Internet (TCP/IP) ou rede de celular (GSM) via protocolo General Packet Radzo Service (GPRS)
278

Aplikace RFID v obchodní logistice

Hromádková, Hana January 2005 (has links)
Diplomová práce pojednává o možnostech využití radiofrekvenční technologie (RFID) v logistice, vysvětluje její funkční principy a současné použití na případových studiích třech významných retailových společností: Kaufhof, Marks and Spencer, Tesco. Vysvětluje výhody technologie oproti čárovým kódům, mapuje standardizaci na národní a mezinárodní úrovni a vyjmenovává faktory, které brzdí celosvětové rozšíření RFID. V závěru nastiňuje budoucnost této technologie.
279

Využití technologií automatické identifikace při řízení firmy / The automatic identification technologies usage for company management

Švecová, Martina Bc. January 2007 (has links)
Cílem práce je ukázat jakým způsobem lze využít moderní technologie automatické identifikace v procesech řízení firmy. Průmyslové použití čárových kódů v České republice lze vysledovat zhruba od 90 let 20. století, kdy se začaly běžně používat především z důvodu příchodu obchodních řetězců a z toho vyplývajícího zautomatizování identifikace prodávaného zboží. Tato práce je zaměřena nejen na dnes již běžné technologie čárových kódů, ale také na nově nastupující radiofrekvenční identifikaci a řízení pomocí hlasu.
280

Gestão de controlo de acessos

Moreira, Pedro Alexandre Teixeira January 2009 (has links)
Tese de mestrado. Engenharia Electrotécnica e de Computadores (Área de especialização em Tecnologias da Informação para Gestão Empresarial). Faculdade de Engenharia. Universidade do Porto. 2009

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