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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.
151

Printability and environmental testing using silver-based conductive flexographic ink printed on a polyamide substrate /

Cole, Kathryn O. January 2007 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 84-86).
152

Personal Privacy Protection within Pervasive RFID Environments

Hedefine, Eeva Kaarina January 2006 (has links) (PDF)
No description available.
153

Filtering Techniques for Improving Radio-Frequency Identification Machine Control

January 2012 (has links)
abstract: Human operators have difficulty driving cranes quickly, accurately, and safely because of the slow response of heavy crane structures, non-intuitive control interfaces, and payload oscillations. Recently, a novel hand-motion crane control system has been proposed to improve performance by coupling an intuitive control interface with an element that reduces the complex oscillatory behavior of the payload. Hand-motion control allows operators to drive a crane by simply moving a hand-held radio-frequency tag through the desired path. Real-time location sensors are used to track the movements of the tag and the tag position is used in a feedback control loop to drive the crane. An input shaper is added to eliminate dangerous payload oscillations. However, tag position measurements are corrupted by noise. It is important to understand the noise properties so that appropriate filters can be designed to mitigate the effects of noise and improve tracking accuracy. This work discusses implementing filtering techniques to address the issue of noise in the operating environment. Five different filters are used on experimentally-acquired tag trajectories to reduce noise. The filtered trajectories are then used to drive crane simulations. Filter performance is evaluated with respect to the energy usage of the crane trolley, the settling time of the crane payload oscillations, and the safety corridor of the crane trajectory. The effects of filter window lengths on these parameters are also investigated. An adaptive filtering technique, namely the Kalman filter, adapts to the noise characteristics of the workspace to minimize the tag tracking error and performs better than the other filtering techniques examined. / Dissertation/Thesis / M.S. Bioengineering 2012
154

The viability of introducing radio frequency identification to the South African truck tyre market: a cross-sectional study

Francis, Merwin January 2013 (has links)
Radio Frequency Identification (RFID) is revolutionizing business practices across industries worldwide as means for its commercial application continue to be developed. It is surpassing barcoding as the preferred means of product identification due to its’ ability to identify goods at item-level as opposed to batch- or type identification, and with no line-of-sight requirements for item detection. Although many industries have successfully employed the technology and are reaping the rewards, RFID’s adoption in the truck tyre industry is still in its infant stage. A small number of documented cases discuss the limited roll-out and testing of RFID effectiveness in satisfying the demands and expectations associated with this specific application. This study is aimed at evaluating the viability of introducing RFID to the South African market. The market readiness is reflected in the perceptions of Continental Tyre South Africa’s (CTSA’s) customers regarding the perceived benefits of RFID. More importantly, it is revealed in how it affects customers’ buying behaviour and, by implication, the impact on CTSA’s sales. The results of the study also reveal critical aspects unique to the South African truck tyre market which could potentially be addressed through the introduction of RFID. These aspects form the basis of the conclusions and recommendations for future actions by CTSA.
155

Implementace logistických technologií v potravinářském průmyslu / Implementation of logistic technologies in food processing industry.

VIGH, Ladislav January 2012 (has links)
Main goal of graduation theses is analysis possibilities to use logistic technologies in food company Fontea. This analysis is focused on material and informative flows in her logistic chain including analysis of key factors. These factors are important for implementation of chosen technologies. Subsequently were analyzed customer department, sales department, production department, purchasing department and shipping department. There were found several principal problems. Customer department staffs have a problem with finding actual quantity of manufactured finished goods, because up-dating of computer system is provided only once a day. Most of orders are inserted manually in computer system. Staffs are not able to find out charges of manufactured finished goods. Similar problems were discovered also in the next departments. To fix the problem were suggested implementation of Quick Response and automatic identification of barcodes and Radio Frequency Identification (RFID).
156

Avaliação de projetos logísticos de RFID aplicados na indústria aeronáutica brasileira / RFID logistics project evaluation applied to the Brazilian aircraft industry

Castro, Jefferson Inácio de [UNESP] 09 December 2014 (has links) (PDF)
Made available in DSpace on 2015-04-09T12:28:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-12-09Bitstream added on 2015-04-09T12:47:59Z : No. of bitstreams: 1 000817267.pdf: 2036490 bytes, checksum: 2a66a1a45fbc89e11bd5d6f636e5887b (MD5) / A tecnologia de Radio Frequency Identification (RFID) tornou-se um tema importante desde 2006, quando vários autores começaram a avaliá-la. A aplicação de RFID para processos industriais tem uma abordagem estratégica, objetivando a melhoria da satisfação dos clientes e criar novas oportunidades de negócios, bem como uma abordagem operacional com foco na eficiência operacional e na flexibilidade dos processos. A tecnologia é aplicada na logística e nos demais processos da cadeia de suprimentos com o objetivo do rastreamento dos materiais, aumento de visibilidade, aumento da eficiência operacional, redução dos desvios do processo e aumento da acessibilidade do inventário. Neste cenário, a presente dissertação tem como objetivo a avaliação de projetos logísticos aplicados à indústria aeronáutica brasileira com o uso do AHP - Analytic Hierarchy Process com ratings - passando pela identificação e avaliação das características que motivam e restringem a utilização da tecnologia através de uma revisão da literatura e pesquisa de campo / Research on Radio Frequency Identification technology (RFID) has become an important issue since 2006 and several authors have begun to assess this technology. The application of RFID to industrial processes has a strategic approach, seeking to improve customer satisfaction and new business opportunities, and has an operational approach focusing on operational efficiency and flexibility of the processes. There is a great application of RFID in logistics, warehouse and supply chain processes seeking tracking materials, increase supply chain visibility, labor savings, shrinkage reduction and inventory visibility. In this scenario, this paper aims to evaluate logistics projects applied to the brazilian aircraft industry using the AHP - Analytic Hierarchy Process with ratings, in addition to the identification and evaluation of the characteristics that motivate and restrict the use of technology through a literature review and a survey
157

The dynamic impact of monetary policy on regional housing prices in the US: Evidence based on factor-augmented vector autoregressions

Fischer, Manfred M., Huber, Florian, Pfarrhofer, Michael, Staufer-Steinnocher, Petra January 2018 (has links) (PDF)
In this study interest centers on regional differences in the response of housing prices to monetary policy shocks in the US. We address this issue by analyzing monthly home price data for metropolitan regions using a factor-augmented vector autoregression (FAVAR) model. Bayesian model estimation is based on Gibbs sampling with Normal-Gamma shrinkage priors for the autoregressive coefficients and factor loadings, while monetary policy shocks are identified using high-frequency surprises around policy announcements as external instruments. The empirical results indicate that monetary policy actions typically have sizeable and significant positive effects on regional housing prices, revealing differences in magnitude and duration. The largest effects are observed in regions located in states on both the East and West Coasts, notably California, Arizona and Florida. / Series: Working Papers in Regional Science
158

Estudo exploratório da adoção da tecnologia RFID no controle de estoque de almoxarifado com base na opinião da área operacional de usinas sucroalcooleiras /

Alves, Paulo Roberto. January 2016 (has links)
Orientador: Barbara Stolte Bezerra / Banca: José Souza Rodrigues / Banca: André Luiz Barbosa Nunes da Cunha / Resumo: O objetivo desta pesquisa consiste em identificar e analisar as variáveis internas e/ou externas que se caracterizam como sendo fatores na adoção da tecnologia RFID no controle de estoques de materiais, especificamente nas áreas denominadas almoxarifados em usinas pertencentes ao setor sucroalcooleiro no atual cenário produtivo e econômico nacional. A escolha de usinas do setor sucroalcooleiro foi devido a relevância econômica que representou no ano de 2013, 2% do PIB nacional, montante este equivalente a US$ 43 bilhões, e tendo o valor bruto movimentado pela cadeia superior a US$ 100 bilhões. Para tanto foram empregados os métodos de revisão bibliográfica e survey. Como principais resultados foi possível observar que em um universo de 32 respondentes com cargos de liderança, 12,5% dos respondentes desconhecem a tecnologia RFID. De um total de 28 respondentes que demonstraram conhecer a tecnologia, 100% retornaram não ter a tecnologia implementada em suas operações, somente 28,6% entendem que a empresa já tenha avaliado em algum momento a possibilidade de implementação, e 60,7% acreditam que a implementação seja uma operação complexa, demonstrando que estes fatores contribuem negativamente para a adoção da tecnologia nas operações de almoxarifados em usinas. / Abstract: The objective of this research is to identify and analyze the internal and/or external variables that are characterized as being factors in the adoption of RFID technology in the control materials inventory, specifically in the areas called stockrooms in plants belonging to the sugarcane sector in the current production scenario and national economic. The choice of plants of this sector was due to the economic importance which represented in 2013, 2% of GDP, this amount equivalent to US $ 43 billion, taking the gross busy the upper chain to $ 100 billion. Therefore, we used the methods of literature review and survey. The main results we observed that in a universe of 32 respondents with leadership positions, 12.5% of respondents are unaware of the RFID technology. A total of 28 respondents who knew about the technology, 100% returned not have the technology implemented in its operations, only 28.6% believe that the company has been evaluated at some point the possibility of implementing, and 60.7% believe that implementation is a complex operation, demonstrating that these factors negatively contribute to the adoption of technology in warehouses operations in plants. / Mestre
159

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.
160

Controle PID MultivariÃvel Descentralizado: Sintonia e AplicaÃÃo PrÃtica / CONTROL PID MULTIVARIABLE DECENTRALIZED: TUNING AND PRACTICAL APPLICATION

Guilherme Medeiros BarÃante 09 December 2011 (has links)
RESUMO BarÃante, G. M. CONTROLE PID MULTIVARIÃVEL DESCENTRALIZADO: SINTONIA E APLICAÃÃO PRÃTICA. 2011. 88 f. DissertaÃÃo (Mestrado em Engenharia ElÃtrica)-Centro de Tecnologia, Universidade Federal do CearÃ, Fortaleza, Brasil, 2011. Nesta dissertaÃÃo de mestrado, desenvolvem-se projetos de controladores PI (Proporcional-Integral) e PID (Proporcional-Integral-Dervativo) para os casos SISO (Simple- Input, Simple- Output) e MIMO (Multiples- Input, Multiples-Output). A proposta do trabalho à combinar tÃcnica do relà SISO e PID SISO baseado em especificaÃÃes de margem de fase e margem de ganho para sintetizar um mÃtodo de projeto de controladores PID MIMO multivariÃvel com sintonia automÃtica ou auto-sintonia. Uma Ãnfase especial à dada aos projetos de controladores PID MIMO atravÃs do mÃtodo do relà como elemento de identificaÃÃo frequencial das malhas a serem controladas. Dois mÃtodos de projetos MIMO sÃo abordados em profundidade e aplicados em sistemas simulados e em duas aplicaÃÃes prÃticas a saber: um processo formado pelas malhas de uma incubadora neonatal e em um processo de tanques duplos acoplados. Todos estes processos apresentam fortes interaÃÃes entre as malhas de controle. O primeiro mÃtodo de projeto multivariÃvel refere-se a um projeto sequencial no qual os controladores sÃo projetados de forma sistemÃtica e considerando, a cada passo, a interaÃÃo entre as malhas. Esse mÃtodo à eficiente e simples e apresenta vantagens tais como: i) à conceitualmente simples e mantÃm a estrutura descentralizada e sequencial com o projeto SISO das malhas de controle; ii) estabilidade e robustez sÃo garantidos a cada passo do projeto; iii) desde que o mÃtodo seja autoajustÃvel, nenhum conhecimento do processo à requerido. O segundo mÃtodo de projeto de controladores multivariÃveis refere-se a uma generalizaÃÃo do mÃtodo do ÃstrÃm e Wittenmark, tambÃm conhecido como mÃtodo do ponto crÃtico, para sistemas MIMO. Para se projetar controladores PID com essa abordagem, um entendimento do conceito de superfÃcie crÃtica e locais caracterÃsticos para os casos de processos MIMO deve ser bem estabelecido. Este mÃtodo apresenta ainda muitos aspectos a serem pesquisados e propostas para solucionar vÃrios aspectos teÃricos e prÃticos devem ser lanÃados em breve. Aspectos prÃticos e teÃricos do mÃtodo DRF (Decentrilized Relay Feedback) que utiliza nÃo linearidades do tipo relà para processo MIMO sÃo abordados atravÃs de novas soluÃÃes para os mÃltiplos ciclos limites. Por fim, aplicaÃÃes simuladas e experimentais parecem apontar para vantagens do projeto de controladores PID descentralizados atravÃs do mÃtodo do ponto crÃtico, lembrando que a escolha do melhor mÃtodo de projeto sempre depende de vÃrios aspectos tais como da robustez, estabilidade e complexidade. Esgotar este contexto nÃo constitui a proposta deste trabalho. / ABSTRACT Medeiros, G. M. 2011. 88 f. CONTROL PID MULTIVARIABLE DECENTRALIZED: TUNING AND PRACTICAL APPLICATION. Dissertation (Master in Electrical Engineering)-Technological Center, Federal University of CearÃ, Fortaleza, Brazil, 2011. This dissertation develops PI controllers (Proportional-Integral) and PID (Proportional-Integral-Dervativo) projects for SISO (Simple Input Simple Output) and MIMO (Multiple Input Multiple Output). The objective of this study is to combine the techniques of SISO and SISO PID controllers based on specification of gain and phase margins to synthesize a new design method of multivariable MIMO PID controllers with self-tuning or automatic tuning. Special emphasis is given to projects MIMO PID controllers using the relay method as frequency identification of the loops to be controlled. Two MIMO design methods are discussed in this work. These methods are applied in simulation systems and two practical applications: a process formed by neonatal incubator loops and a process of double attached tanks. These processes have strong interaction between control loops. The first method of multivariable design is a sequential design which the controllers are designed systematically and considering the interaction between loops for each step. This method is efficient and simple and has advantages such as: i) decentralized structure and sequential SISO design of control loops, ii) stability and robustness is guaranteed every step of the project; iii) the method is self-adjusting, therefore process knowledge is not required. The second method of multivariable controller design refers to a generalization of the ÃstrÃm and Wittemark method, also known as critical point method for MIMO systems. The concept of critical surface and local characteristics for the cases of MIMO processes must be well established to design PID controllers with this approach. Many theoretical and practical aspects still need to be investigated in this method. Practical and theoretical aspects of the DRF method (Decentralized Relay Feedback) using nonlinearities like relay MIMO process are addressed through new solutions for multiple limit cycles. The present study showed that simulated and experimental applications seem to point to the advantages of decentralized PID controller design that utilizes the critical point method. The choice of the best method of project always depends on several aspects such as the robustness, stability and complexity, context and exhaust which are not the purpose of this study.

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