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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.
351

Vart tog den vägen : En studie om spårbarhet inom produktionsflöden

Köster, Simon, Falk, Joakim January 2017 (has links)
No description available.
352

Structural Health Monitoring Inside Concrete and Grout Using the Wireless Identification and Sensing Platform (WISP)

Delgado Cepero, Elicek 21 March 2013 (has links)
This research investigates the implementation of battery-less RFID sensing platforms inside lossy media, such as, concrete and grout. Both concrete and novel grouts can be used for nuclear plant decommissioning as part of the U.S. Department of Energy’s (DOE’s) cleanup projects. Our research examines the following: (1) material characterization, (2) analytical modeling of transmission and propagation losses inside lossy media, (3) maximum operational range of RFID wireless sensors embedded inside concrete and grout, and (4) best positioning of antennas for achieving longer communication range between RFID antennas and wireless sensors. Our research uses the battery-less Wireless Identification and Sensing Platform (WISP) which can be used to monitor temperature, and humidity inside complex materials. By using a commercial Agilent open-ended coaxial probe (HP8570B), the measurements of the dielectric permittivity of concrete and grout are performed. Subsequently, the measured complex permittivity is used to formulate analytical Debye models. Also, the transmission and propagation losses of a uniform plane wave inside grout are calculated. Our results show that wireless sensors will perform better in concrete than grout. In addition, the maximum axial and radial ranges for WISP are experimentally determined. Our work illustrates the feasibility of battery-less wireless sensors that are embedded inside concrete and grout. Also, our work provides information that can be used to optimize the power management, sampling rate, and antenna design of such sensors.
353

Chaos Based RFID Authentication Protocol

Chung, Harold January 2013 (has links)
Chaotic systems have been studied for the past few decades because of its complex behaviour given simple governing ordinary differential equations. In the field of cryptology, several methods have been proposed for the use of chaos in cryptosystems. In this work, a method for harnessing the beneficial behaviour of chaos was proposed for use in RFID authentication and encryption. In order to make an accurate estimation of necessary hardware resources required, a complete hardware implementation was designed using a Xilinx Virtex 6 FPGA. The results showed that only 470 Xilinx Virtex slices were required, which is significantly less than other RFID authentication methods based on AES block cipher. The total number of clock cycles required per encryption of a 288-bit plaintext was 57 clock cycles. This efficiency level is many times higher than other AES methods for RFID application. Based on a carrier frequency of 13.56Mhz, which is the standard frequency of common encryption enabled passive RFID tags such as ISO-15693, a data throughput of 5.538Kb/s was achieved. As the strength of the proposed RFID authentication and encryption scheme is based on the problem of predicting chaotic systems, it was important to ensure that chaotic behaviour is maintained in this discretized version of Lorenz dynamical system. As a result, key boundaries and fourth order Runge Kutta approximation time step values that are unique for this new mean of chaos utilization were discovered. The result is a computationally efficient and cryptographically complex new RFID authentication scheme that can be readily adopted in current RFID standards such as ISO-14443 and ISO-15693. A proof of security by the analysis of time series data obtained from the hardware FPGA design is also presented. This is to ensure that my proposed method does not exhibit short periodic cycles, has an even probabilistic distribution and builds on the beneficial chaotic properties of the continuous version of Lorenz dynamical system.
354

Design and Optimization of RFID Systems

Irfan, Nazish January 2014 (has links)
This thesis deals with the design of cost-effective large-scale RFID networks from both software and hardware aspects. To start with, different computer-aided tools were developed to maximize performance. The first set of algorithms focused on the elimination of redundant readers to minimize the cost and interference in large-scale RFID networks. For validation, uniform reader coverage was assumed, as widely used in most available publications. Then, both omni-directional and directional commercial reader antenna data were included for more reliability. Besides redundancy, an efficient physical placement of readers was also investigated by considering both uniform and random distribution over space. For this purpose, genetic-based algorithms have been proposed to increase reader coverage using commercial reader antenna beams. Energy consumption is also a critical design parameter for dense RFID networks. Therefore, a third set of algorithms was developed to efficiently minimize the energy consumption of large-scale RFID systems. Note that all above optimization techniques were achieved without compromising the whole RFID network performance. To further optimize cost and performance of large-scale RFID networks, a hardware approach through reader antenna design has been considered. In fact, since different RFID frequency bands have been assigned worldwide, large-scale RFID networks implemented in industrial parks, airports, or international trade zones, may deal with imported merchandise using tags operating at different frequencies. Therefore, in-house single and dual-band microstrip and CPW fed monopole antennas were successfully designed and tested to improve system adaptability to various RFID standards. These antennas were designed using both electromagnetic commercial simulators (HFSS) and in-house FDTD-based techniques. Finally, to further extend dense RFID network capabilities, one may implement a substantial number of readers and antennas with small reading ranges to cover a large monitoring area, or use high gain phased array antenna system for an extended reading range of an RFID reader for a smaller number of total reader deployments. Therefore, a phased antenna array system can be an efficient alternative for dense RFID networks. Thus, a switched beam network to control the phase of the radiating elements of the array has been successfully designed and tested.
355

Indoor Localization Using Augmented UHF RFID System for the Internet-of-Things

Wang, Jing January 2017 (has links)
Indoor localization with proximity information in ultra-high-frequency (UHF) radio-frequency-identification (RFID) is widely considered as a potential candidate of locating items in Internet-of-Things (IoT) paradigm. First, the proximity-based methods are less affected by multi-path distortion and dynamic changes of the indoor environment compared to the traditional range-based localization methods. The objective of this dissertation is to use tag-to-tag backscattering communication link in augmented UHF RFID system (AURIS) for proximity-based indoor localization solution. Tag-to-tag backscattering communication in AURIS has an obvious advantage over the conventional reader-to-tag link for proximity-based indoor localization by keeping both landmark and mobile tags simple and inexpensive. This work is the very first thesis evaluating proximity-based localization solution using tag-to-tag backscattering communication.Our research makes the contributions in terms of phase cancellation effect, the improved mathematical models and localization algorithm. First, we investigate the phase cancellation effect in the tag-to-tag backscattering communication, which has a significant effect on proximity-based localization. We then present a solution to counter such destructive effect by exploiting the spatial diversity of dual antennas. Second, a novel and realistic detection probability model of ST-to-tag detection is proposed. In AURIS, a large set of passive tags are placed at known locations as landmarks, and STs are attached mobile targets of interest. We identify two technical roadblocks of AURIS and existing localization algorithms as false synchronous detection assumption and state evolution model constraints. With the new and more realistic detection probability model we explore the use of particle filtering methodology for localizing ST, which overcomes the aforementioned roadblocks. Last, we propose a landmark-based sequential localization and mapping framework (SQLAM) for AURIS to locate STs and passive tags with unknown locations, which leverages a set of passive landmark tags to localize ST, and sequentially constructs a geographical map of passive tags with unknown locations while ST is moving in the environment. Mapping passive tags with unknown locations accurately leads to practical advantages. First, the localization capability of AURIS is not confined to the objects carrying STs. Second, the problem of failed landmark tags is addressed by including passive tags with resolved locations into landmark set. Each of the contributions is supported by extensive computer simulation to demonstrate the performance of enhancements.
356

Eloping Prevention, Occupancy Detection and Localizing System for Smart Healthcare Applications

Roshan, Muhammad Hassan Ahmad January 2014 (has links)
The purpose of this thesis is to devise a system based on RFID (Radio Frequency IDentification) that can be used for smart healthcare applications. Location estimation, eloping prevention and occupancy detection are monitoring applications of smart healthcare which can provide very useful information for the nursing and administration staff of the nursing-home/hospital. The introduction of ubiquitous networking along with the concepts such as Internet of Things (IoT) can certainly help achieve the goals of smart healthcare. RFID technology has features, such as low power and small size, which makes this technology suitable for researching solutions for smart healthcare. Today several nursing-home/hospital monitoring solutions exist in the market and academia alike. The solutions marketed commercially are very expensive whereas the solutions from academia provides solutions to isolated problems but a comprehensive all in one solution that can meet the need of smart healthcare monitoring applications is missing. In this thesis we present a system that is low cost and suitable for accommodating a number of the smart healthcare applications including occupancy detection, location estimation, eloping prevention and access control. The solution is implemented on a customized Openbeacon Active RFID System (OARS). Active RFID based proximity detection is the core of our system. Practical experiments based on novel Proximity Detection based Weighted Centroid Localization (PD-WCL) method were done to analyze the performance of the system with different applications to highlight the applicability of the system.
357

Specifika logistických řetězců v distribuci a prodeji oděvní konfekce / Specific Features of Logistics Chains Related to Garments' Distribution and Sale

Sloupenská, Adriana January 2007 (has links)
Práce hodnotí stav distribuce oděvní konfekce a potenciál opatřování zdrojů v zemích s levnými vstupy. Ještě nikdy nebylo spektrum nabídky oděvního průmyslu tak široké a střídání módních vln tak časté. Nároky na kvalitu logistického řetězce rostou a delegování odpovědnosti za jeho řízení je v současné době běžné. Práce mapuje uspořádání distribučních cest a popisuje procesy a služby, se kterými se zboží pří své cestě za konečným zákazníkem setká. Na příkladu konkrétního poskytovatele logistických služeb je provedena analýza, která ukazuje posílení postavení tohoto článku v rámci logistického řetězce.
358

Aplikace radiofrekvenční technologie na Masarykově onkologickém ústavu / RFID implementation at Masaryk Memorial Cancer Institute (MOÚ)

Halenková, Kateřina January 2009 (has links)
The first part introduces the RFID technology and its application in the healthcare and pharma. The second part deals with the particular RFID application in the process of preparation and aplication of cytostatics at MOU. It includes process analysis, identification of areas where there is a lack in usage of technology potential, suggestions on how to increase the benefits of the implementation, as well as identification of factors that have impact on the valuation of RFID projects.
359

Aplikace logistiky ve Vědecké knihovně Olomouc / Logistics applications in Research library in Olomouc

Vymazalová, Jana January 2011 (has links)
This master's thesis investigates the of logistics of Research library in Olomouc and offers improvements. I introduce the Czech library system and then concentrate on the Olomouc library's history and the operations of individual departments. I found that the depositories could be improved in aspects such storage and overall building condition. The library uses barcodes for loan administration. To introduce the options of improvements of the library, I describe new technologies that are in use abroad such as RFID tags or shelf stacker in the storage rooms. I believe that the efficacy of library operations would improve should they be concentrated in one building and offer further enhancements to the daily running of the library.
360

RFID přístupový systém v místnosti / RFID based access system in rooms

Mego, Roman January 2012 (has links)
The master’s thesis aims to design an access control system using the RFID technology. The system should reduce security risks associated with its use. While working on project two devices were created. First is the access terminal operating on frequency of 13.56 MHz and second is the RFID reader for PC operating at frequency 125 kHz. Software for devices was created as well as system control application for PC. The document contains an overview of the RFID principles and possibility of implementation access control system. Next part of the project describes in detail step by step the process of designing electrical circuit for system parts. Last part talks about realized software, libraries which are used and the system control application for PC.

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