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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.
61

Consumer concerns towards privacy: An empirical study

Nicolaou, Maria 01 January 2006 (has links)
The purpose of the study was to determine consumer attitudes toward privacy and the influence of demographic factors on these attitudes. The study also sought to determine the willingness of participants to disclose selected individual information items and determine the awareness and acceptance level of technological innovations such as radio frequency identifiers (RFID) as they relate to privacy. A quantitative instrument was developed and a convenience sample of university students (N=203) was tested. Results showed that educational background played a role in the way participants perceived the applications of RFID.
62

Selection process of auto-ID technology in warehouse management : a Delphi study

Hassan, Mayadah January 2014 (has links)
In a supply chain, a warehouse is a crucial component for linking all chain parties. Automatic identification and data capture (auto-ID) technology, e.g. RFID and barcodes are among the essential technologies in the 21st century knowledge-based economy. Selecting an auto-ID technology is a long term investment and it contributes to improving operational efficiency, achieving cost savings and creating opportunities for higher revenues. The interest in auto-ID research for warehouse management is rather stagnant and relatively small in comparison to other research domains such as transport, logistics and supply chain. However, although there are some previous studies that explored factors for the auto-ID selection decision in a warehouse environment, those factors (e.g., operational factors) have been examined separately and researchers have paid no attention to all key factors that may potentially affect this decision. In fact, yet there is no comprehensive framework in the literature that comprehensively investigates the critical factors influencing the auto-ID selection decision and how the factors should be combined to produce a successful auto-ID selection process in warehouse management. Therefore, the main aim of this research is to investigate empirically the auto-ID technology-selection process and to determine the key factors that influence decision makers when selecting auto-ID technology in the warehouse environment. This research is preceded by a comprehensive and systematic review of the relevant literature to identify the set of factors that may affect the technology selection decision. The Technology-Organisation-Environment (TOE) framework has been used as lens to categorise the identified factors (Tornatzky & Fleischer, 1990). Data were collected by conducting first a modified (mixed-method) two-round Delphi study with a worldwide panel of experts (107) including academics, industry practitioners and consultants in auto-ID technologies. The results of the Delphi study were then verified via follow-up interviews, both face-to-face and telephone, carried out with 19 experts across the world. This research in nature is positivist, exploratory/descriptive, deductive/inductive and quantitative/qualitative. The quantitative data were analysed using the statistical package for social sciences, SPSS V.18, while the qualitative data of the Delphi study and the interviews were analysed manually using quantitative content analysis approach and thematic content analysis approach respectively. The findings of this research are reported on the motivations/reasons of warehouses in seeking to use auto-ID technologies, the challenges in making an auto-ID decision, the recommendations to address the challenges, the key steps that should be followed in making auto-ID selection decision, the key factors and their relative importance that influence auto-ID selection decision in a warehouse. The results of the Delphi study show that the six major factors affecting the auto-ID selection decision in warehouse management are: organisational, operational, structural, resources, external environmental and technological factors (in decreasing order of importance). In addition, 54 key sub-factors have been identified from the list of each of the major factors and ranked in decreasing order of the importance mean scores. However, the importance of these factors depends on the objectives and strategic motivations of warehouse; size of warehouse; type of business; nature of business environment; sectors; market types; products and countries. Based on the Delphi study and the interviews findings, a comprehensive multi-stage framework for auto-ID technology selection process has been developed. This research indicates that the selection process is complex and needs support and closer collaboration from all participants involved in the process such as the IT team, top management, warehouse manager, functional managers, experts, stockholders and vendors. Moreover, warehouse managers should have this process for collaboration before adopting the technology in order to reduce the high risks involved and achieve successful implementation. This research makes several contributions for both academic and practitioners with auto-ID selection in a warehouse environment. Academically, it provides a holistic multi-stage framework that explains the critical issues within the decision making process of auto-ID technology in warehouse management. Moreover, it contributes to the body of auto-ID and warehouse management literature by synthesising the literature on key dimensions of auto-ID (RFID/barcode) selection decision in the warehouse field. This research also provides a theoretical basis upon which future research on auto-ID selection and implementation can be built. Practically, the findings provide valuable insights for warehouse managers and executives associated with auto-ID selection and advance their understanding of the issues involved in the technology selection process that need to be considered.
63

Indirect effects of agricultural intensification on tree swallow (Tachycineta bicolor) foraging behaviour, body condition, and physiology

2015 August 1900 (has links)
Throughout North America, many species of aerial insectivorous birds – birds that capture flying insects – have exhibited sharp declines, with tree swallows (Tachycineta bicolor) experiencing a 2.8% annual decline in Canada since 1989. The timing of these declines coincides with major changes in agriculture, perhaps signaling a potential causal link. Declines may be influenced indirectly by agriculturally-driven reductions in the abundance of the swallow’s main diet of aerial insects through increased agrochemical use, wetland drainage and cropping intensity. My objectives were to determine how aerial insect abundance and biomass vary across an agricultural landscape in the Canadian Prairies, and determine how breeding tree swallows respond in terms of (i) foraging behaviours and return rates, (ii) body condition, and (iii) selected physiological responses (i.e. oxidative stress and feather corticosterone). Artificial nest-boxes were erected at each of 5 sites with varying levels of agricultural intensification in south-central Saskatchewan, 2012-2014. Insect abundance and biomass were monitored daily using passive aerial samplers at each of the sites throughout the breeding season. Tree swallows adults (n = 596) and nestlings (n = 1107) from each nest were captured, banded, measured and blood and feather sampled to determine condition and physiological status. In 2014, radio frequency identification (RFID) technology was employed at a subset of nest-boxes to determine adult foraging rates and durations. Despite strong differences in land use characteristics among sites, insect abundance and biomass varied by year but were similar between heavily cropped and grassland references sites. Regardless, birds responded to temporal changes in prey abundance and differences were found in measurements of foraging behavior and physiological measures of oxidative stress. Adult foraging rate (number of nest visits/hour) was primarily influenced by wind and nestling age, but was also positively related to daily insect biomass. Foraging intervals (i.e., length of time spent on each trip) differed between agricultural intensities; birds on agricultural sites spent more time away from the nest box, presumably foraging, suggesting reduced nest attentiveness. Return rates were primarily predicted by body condition and brood size from the previous breeding season, but were also higher on grassland sites, suggesting that agricultural sites may be less favorable. Older adults (based on banding records) and females displayed a higher body condition than did younger individuals and males, respectively. Measures of physiology (i.e. total antioxidant counts and oxidative damage) in both adult and nestling swallows were primarily driven by temporal changes in insect biomass and abundance. Similarly, adult body mass and physiology were related to local insect availability, but not land use (agriculture/grassland). Measures of nestling feather corticosterone were unrelated to any of the explanatory variables. These results provide valuable information pertaining to components of individual quality, foraging behaviour, and return status in response to prey availability under differing agricultural land use regimes, which may help to inform conservation strategies for a variety of insectivorous bird species of conservation concern.
64

Data integrity in RFID systems

Alchazidis, Nikolaos. 09 1900 (has links)
One of the main problems that affect the data integrity of passive RFID systems is the collision between the tags. A popular anticollision algorithm which dominates the standards in HF and UHF passive RFID systems is Framed Slotted Aloha (FSA) and some variations of FSA. Throughput and Average time delay of the RFID system which determines the performance/efficiency of the system are reduced rapidly when the number of tags inside the interrogation zone is increased. Using larger frame sizes is not always the solution. This thesis discusses and compares the existing protocols, and proposes a variation of FSA, called Progressing Scanning (PS) algorithm. The PS algorithm divides the tags in the interrogation zone into smaller groups, and gives the ability to the reader to communicate each time with one of them. For performance analysis, the PS algorithm was evaluated with the parameters of a typical passive RFID system at 2.45 GHz . The results showed that the PS algorithm can improve the efficiency of the RFID system and provide a reliable solution for cases with a high density of tags in the area (over 800 tags ).
65

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

Nemoto, Miriam Christi Midori Oishi 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.
66

[en] A MULTI-AGENT SYSTEMS FRAMEWORK FOR RFID APPLICATIONS / [pt] UM FRAMEWORK DE SISTEMAS MULTI-AGENTES PARA APLICAÇÕES RFID

FELIPE FORTES NASCIMENTO 07 February 2006 (has links)
[pt] Esta dissertação propõe um framework de sistemas multi- agentes para aplicações do domínio de Radio Frequency Identification (RFID). Esta tecnologia de identificação automática de objetos vem se desenvolvendo rapidamente e promete substituir brevemente a tecnologia atual de identificação de produtos: código de barras. Além de promover o desenvolvimento de hardware para etiquetas e leitoras RFID, novos padrões de identificação estão sendo propostos, desafiando os desenvolvedores de software a produzirem novas soluções para lidar com o novo e maior volume de dados e com a natureza distribuída das leitoras e leituras de objetos. Esta dissertação propõe um framework projetado utilizando-se a abordagem de sistemas multi-agentes (SMA) capaz de instanciar SMA distribuídos que: - Interagem com a infra-estrutura RFID existente (leitoras, etiquetas e middlewares); - Facilitam a geração de informações com semântica de negócios a partir de dados crus gerados por esta infra-estrutura, e; - Facilitam a implementação de novas funcionalidades decorrentes do leque de aplicações vislumbradas pelo surgimento de RFID. / [en] Radio Frequency Identification (RFID) technology along with the Electronic Product Code (EPC) created a new complex environment for warehouses systems and supply chain systems in general. The EPC specification created one more level of identification: the product instance. This new level of identification had blown the volume of data being managed by applications. That fact, along with the deployment of distributed RFID readers, causes the necessity of new applications capable of interacting with this infrastructure and capable of processing, filtering and interpreting these new data. This work proposes a framework for distributed multi-agent systems capable of interacting with a deployed RFID infrastructure.
67

A Real-Time Laboratory Testbed For Evaluating Localization Performance Of WIFI RFID Technologies

Assad, Muhammad Ali 04 May 2007 (has links)
A realistic comparative performance evaluation of indoor Geolocation systems is a complex and challenging problem facing the research community. This is due to the fact that performance of these systems depends on the statistical variations of the fading multipath characteristics of the wireless channel, the density and distribution of the access points in the area, and the number of the training points used by the positioning algorithm. This problem, in particular, becomes more challenging when we address RFID devices, because the RFID tags and the positioning algorithm are implemented in two separate devices. In this thesis, we have designed and implemented a testbed for comparative performance evaluation of RFID localization systems in a controlled and repeatable laboratory environment. The testbed consists of a real-time RF channel simulator, several WiFi 802.11 access points, commercial RFID tags, and a laptop loaded with the positioning algorithm and its associated user interface. In the real-time channel simulator the fading multipath characteristics of the wireless channel between the access points and the RFID tags is modeled by a modified site-specific IEEE 802.11 channel model which combines this model with the correlation model of shadow fading existing in the literature. The testbed is first used to compare the performance of the modified IEEE 802.11 channel model and the Ray Tracing channel model previously reported in the literature. Then, the testbed with the new channel model is used for comparative performance evaluation of two different WiFi RFID devices.
68

Investigating the design of Smart Objects in the domain of forgetfulness

Farion, Christine January 2018 (has links)
When we forget things, we feel anxious which can impact our day negatively. Some individuals believe they are forgetful, so emphatically, it disrupts their day. There has been little discussion about perceived forgetfulness in design and HCI, combined with few studied smart objects to aid with memory. However, embedded systems, radio frequency identification (RFID) and HCI research provides inspiration towards creating a solution. Challenges of creating a day-to-day smart object that can enhance a user's lifestyle are explored and recommended design guidelines for creating a smart object in a specific domain are the focus of this thesis. Using an experience-centred approach, 'Message Bag' and 'Tag Along' are two purpose built object-based memory aids that have emerged as a result of investigating the design processes for smart objects. The work examines smart objects in the context of forgetting what items to pack in a bag. A solution presented is a device consisting of an RFID system involving (a) pre-tagging essential items; (b) scanning those tagged items and; (c) viewing a corresponding light illuminate, to communicate to the user. Although the conceptual model is simple, success depends on a combination of technical design, usability and aesthetics. These scanning interactions result in a person feeling more confident as suggested through autoethnography reporting, real-world, third person engagements - single user walkouts, conference demos, professional critiques, and residential weekends with potential users (focus group) studies conducted. My work involved extensive autobiographical research and design-led enquiries. Testing was undertaken with investigative prototypes, followed by field testing high-fidelity prototypes. This involved an in-the-wild comparative study involving six users over several months. Results show that people feel more confident and respondents claim no longer needing to continually check items are packed, thus 'gaining time', and feeling less forgetful. Although the application of RFID is not new to ubiquitous computing, this implementation, styling and system immediacy is novel. This thesis presents the development of ten prototypes as well as design guidelines. The research provides a solid base for further exploration, and includes discovery of the importance of a user's style universe and extreme ease-of-use. I conclude with the presentation of early positive results including; (i) the unique form factor becomes a reminder itself and; (ii) usability coupled with the intuitive nature of the system is shown to be essential. We found that when you are creating a smart object, usability and an intuitive nature is even more important than in a standard system. When dealing within the domain of forgetfulness, this is paramount.
69

An inductive RFID system with build-in asynchronous ECC crypto-processor. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Radio Frequency Identification (RFID) has received a great deal of attention in past decades. It is an automatic identification system by replying and retrieving data remotely using RFID transponders. Basically, RFID systems can be divided into three main categories: short transmission range, medium transmission range, and long transmission range. / Short and medium range RFIDs generally are passive transponders while long range RFID is of either passive or active type. In this thesis, a short transmission range RFID transponder is presented. This is a passive transponder which generates power for internal circuitry by inductive coupling. For automatic identification applications such as electronic money tickets, the requirements of endurance, weight, size as well as cost appeal to use passive transponder rather than active transponder. Researches on the passive transponders have created a great challenge for engineers in terms of the tradeoff between power constraints, processing power and data transmission range. / The presented RFID transponder system adheres to the ISO 14443 standard Type B specification communication interface, which operates at 13.56MHz carrier frequency with a maximum read range around 50 mm. This research implemented a low power, high security, and long read range RFID transponder. For the analog RF interface, a series of novel architectures are adopted to improve the data transmission range. The digital core in the presented crypto-processor for data security. The asynchronous architecture has the advantages of fast computation time, low power consumption and small area. These are the attractive reasons to implement the core processing units using an asynchronous architecture. / This RFID system was fabricated with a 0.35um two-poly four-metal standard CMOS process with the silicon area of 1516 um x 1625 um. The measurement results show that the analog RF interface can generate a maximum 5.45mW power while the digital core circuit consumes only 2.77mW. In the wireless communication tests, the transponder read range can reach as far as 50 mm. / Leung, Pak Keung. / "June 2008." / Adviser: Choy Chin Sing. / Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1847. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
70

Tools assisted analog design, from reconfigurable design to analog design automation. / CUHK electronic theses & dissertations collection

January 2011 (has links)
To solve these issues, in this thesis the consistent effort in developing a quick tools assisted IC design platform is presented. First, a reconfigurable solution is proposed for some analog/mixed-signal (AMS) system which requires flexibility to a certain extent, such as a reconfigurable RFID solution for different communicating distances. Second, for further demand of increasing the flexibility, a novel approach for ADA is presented, which provides a highly automatic design flow for analog circuits to realize the "SPEC (Specification) in, GDS out" goal. Considering all kinds of higher order effects and uncertainties under deep submicron or even more advanced technologies, reliable design and fastness in processing are the two major concerns instead of the traditional pure optimization for best performance. To get a good balance among performance, reliability and turnaround time, an Application-Specific design flow with in-built knowledge-based algorithms is applied to deal with ADA issues under advanced technologies, which can quickly provide a reliable design with performance good enough to meet the SPECs for common use. / Unlike the highly automatic flow for digital circuits design, analog design automation (ADA) is still far from mature. For mixed-signal applications, analog circuit occupies only a small part on the layout, but the design requires a considerable amount of time and effort, making ADA extremely attractive. However, there are a lot more considerations to cover in analog design flow than its digital counterparts. In addition, the ever downscaling IC means analog circuits have to face more and more small-size effects, insufficient modelings, and the inaccuracy of classic formulas, which are quite difficult to handle. To solve the problem, various tools and methods have been proposed, but all in a digital-like flow, which are trying to develop general algorithms to realize circuit and layout synthesis. Up to now there is still a lot of problems. / Hong, Yang. / Adviser: C.S. Choy. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 140-150). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

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