Title from PDF of title page (University of Missouri--Columbia, viewed on Feb. 19, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dr. Randy Curry, Thesis Supervisor Includes bibliographical references.

Wireless technology nowadays is developing rapidly throughout the world and also in Hong Kong. The Radio Frequency Identification (RFID) technology is a mature technology which has been applied in a lot of industries in recent years, such as retail, airline, healthcare, pharmaceuticals, logistics, and libraries etc. RFID technology acts as an electronic labelling and data-collection system to identify and track equipment. RFID is a more robust technology than bar coding and does not require line-of-sight to operate. It is able to provide not only the electronic data for unique identification, but also provides a paperless workflow automation solution. The application of palm and wireless technology using the RFID in conjunction with a Web Based Maintenance Service Management System in the Facility Management (FM) has the following advantages: (i) It improves operations and facilitates day-to-day maintenance activities and management of works. (ii) The RFID system helps to improve the management of facilities, decision-making and control of quality by providing enhanced processes and equipment visibility. The RFID system offers a dynamic and centralized approach to facilitate the above FM processes. The objective of this study is to quantify the benefits of RFID technology for the FM. Throughout the study of RFID pilot project carried out by the HKHA, we evaluate the factors that affect the application of RFID system in Hong Kong FM industry. Questionnaires were given out to explore maintenance professionals’ opinions on the satisfaction of RFID system for maintenance of Air Conditioning (A/C) system. The data and hypotheses are analysed by using the statistical methods. The survey concluded that RFID system can improve the user satisfaction rating in FM compared with the paper based system. From the regression analysis, we found that the processes of improvement, quantities of A/C equipment and training & education are more important in determining the satisfaction of RFID system and have positive effect on the use of RFID system. The analysis of various regression models helped to discover the key significant variables that correlated to the satisfaction of using the RFID system. According to the survey findings, the RFID system has proved to be very useful for FM as it offered significant benefits over traditional paper based approaches. From the survey result, we also found that the “Insufficient training for use of RFID system” is the important obstacle to the adoption of RFID system. As education and training are critical for development of staff capability to handle new process requirements and achieve better performance of using the RFID system, HKHA is highly recommended to strengthen the training and education in order to improve their work satisfaction and support the continued use of RFID system. This dissertation offers HKHA managers a valuable perspective on the RFID implementation in their organization. The findings also highlighted the significant potential and obstacle of RFID system for FM. To encourage the use and expand the benefits of RFID system in FM industry, the Government policy is crucial in driving the adoption of RFID system so as to accelerate its diffusion and stimulate the growth of related industries. / published_or_final_version / Housing Management / Master / Master of Housing Management

Counterfeit products, particularly pharmaceuticals, electronic devices, and apparels, are widespread. They threaten consumer safety and cause huge economic losses to licit supply chain partners and governments. Although a number of traditional anti-counterfeiting technologies, such as holograms and chemical tags, are available to combat counterfeiting, they are vulnerable to imitation or being reused. Besides, these technologies are intended to protect individual items, rather than to safeguard an entire supply chain. As such, fake products may likely be injected into the supply chain to hurt end-consumers. Track-and-trace technology based on Radio Frequency Identification (RFID) has recently emerged as a promising tool to combat counterfeiting, because of its automatic and non-line-of-sight capability to identify massive product items. By maintaining an electronic pedigree (e-pedigree) that records the transaction information of product items along the supply chain, this approach stands out for protecting the supply chain against infiltration, eliminating theft and fraud, facilitating recall of defective products, and supporting remote authentication. However, a number of technical and critical issues have yet to be solved for practical implementation of RFID-based track-and-trace anti-counterfeiting. These include generation of accurate initial product e-pedigree in fast moving manufacturing lines, precise e-pedigree updating in batch product distributing and receiving, and fast e- pedigree queries for remote and real-time product authentication from end-customers. Without fully addressing these issues, the accumulated product e-pedigree data would be untrustworthy, rendering any subsequent operations of track-and-trace and product authentication unreliable. This thesis investigates the crucial implementation issues in RFID-based track-and-trace anti-counterfeiting. It firstly presents an innovative track-and-trace anti-counterfeiting system, based on which a TDPS algorithm is proposed for generation of initial product e-pedigree in fast moving production lines. The TDPS overcomes many practical issues, such as tag writing error and tag locking failure, and helps identify the bottleneck of initial product e-pedigree generation. To tackle the bottleneck, the TDPS is further optimized by incorporating a block writing method to enhance the tag EPC writing efficiency and an integration method to balance the overhead of RFID equipment. In product distributing and receiving, a mechanized 3D scanning method is proposed to improve bulk item identification rate and enhance the accuracy and completeness of product e-pedigree. Indeed, RFID-based track-and-trace anti-counterfeiting mandates a relatively high bulk item identification rate for product authentication and e-pedigree updating. Experimental results demonstrate that the mechanized 3D scanning can achieve a bulk item reading rate of up to 98.9%, which largely outperforms the widely documented bulk reading rate (70%) in real applications. In retailing level, the efficiency of e-pedigree queries would hugely impact on customer shopping experience and the effectiveness of track-and-trace anti-counterfeiting. A partition-based method is therefore developed to cluster product e-pedigree data to improve the speed of e-pedigree queries. This approach partitions the accumulated e-pedigree data into fixed and dynamic groups, such that queries are conducted mainly on active data, rather than on the whole historical data sets. By addressing the above key issues, this thesis contributes to making implementation of RFID-based track-and-trace anti-counterfeiting practically viable and reliable. / published_or_final_version / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy

M. Tech. Electrical Engineering / The radio frequency (RF) spectrum is a natural resource used by wireless network operators to provide radio communication and transmission systems. The availability of RF spectrum to various wireless network operators using large bandwidth and more than one channel, as demanded by their offered services, is challenging, due to RF spectrum scarcity and lack of optimal channel selection. On the other hand, the under-utilisation of licensed spectrum by some primary users' (PU's) networks may be improved by the use of dynamic spectrum access (DSA) techniques. Recent research has shown that a large portion of the assigned spectrum is used irregularly, leading to under-utilisation and waste of valuable frequency resources. The notion of cognitive radio (CR) was introduced to increase the effectiveness and efficiency of spectrum consumption. In a cognitive radio network (CRN), each secondary user (SU) is expected to select the best RF spectrum band for opportunistic use when the PUs have temporarily vacated the spectrum allocated to them. The literature has proposed many spectrum selection methods for selecting vacant spectra in CRNs. However, most of these methods do not consider the channel usage pattern over time by PUs and also do not adequately consider the effect that frequent channel-switching might have on the quality of service requirements of the SUs and the throughput of the CR system. Thus, the proposed scheme, which is heuristic-based spectrum selection scheme for minimal channel switching (HBSSS-MCS) and heuristic-based spectrum selection scheme for maximum throughput (HBSSS-MT) addresses these issues. The main study objectives were as follows: 1) Minimise the frequent switching of channels using HBSS-MCS; 2) Maximise the throughput of the CR system using HBSSS-MT. To achieve the objectives of this research work, the following sub-problems were addressed: 1) To investigate the spectrum selection schemes in cognitive radio network (CRN); 2) To design a learning mechanism to facilitate the selection of a suitable channel in the primary network.

Practical issues concerning the implementation and application of genetic algorithms to a number of optimisation problems are the main subjects dealt with in this thesis. Genetic algorithms (GAs) are an attractive class of computational models that attempt to mimic the mechanisms of natural evolution to solve problems in a wide variety of domains. A general purpose genetic algorithm toolkit is developed and applied to the Steiner Problem in Graphs and the Radio Link Frequency Assignment Problem. The toolkit is then extended to cover a large number of parallel genetic algorithm models which are then compared. Solutions for the two case studies are presented with each of the parallel GAs. The thesis begins with a general introduction to genetic algorithms. Holland's original genetic algorithm is described and it's workings illustrated on a simple function minimisation problem. The notion of a schema or similarity template as a basic building block in genetic algorithms is introduced and the schema theory presented. A description of important theoretical results is given and the introduction to genetic algorithms continues with practical issues that are dealt with in the second chapter. The basic components of a modern genetic algorithm are outlined and examples for important components, as found in the Jiterature, are given. The second chapter concludes with the description of a number of applications of genetic algorithms to areas such as function optimisation, combinatorial optimisation, genetic programming, process control and classifier systems. In Chapter 3, the sequential GA toolkit, GAmeter, is described. The General Search paradigm around which the toolkit is implemented is introduced. Notable characteristics of the genetic algorithms kernel and the user interface are mentioned. A popular function optimisation problem is used to illustrate important aspects of genetic algorithms and aspects specific to the toolkit. The Steiner Tree problem in graphs is the first of two case studies examined in detail in this thesis. This is a popular NP-complete problem with a range of applications in areas such as communications, scheduling and printed circuit design. A survey of standard techniques, such as simplification methods, exact algorithms and heuristics is given. Two possible representations for solving it using genetic algorithms are described and applied to a well-known set of problems. Chapter 4 concludes with a comparison of the best GA technique with other heuristics for this problem. The Radio Link Frequency Assignment Problem, described in Chapter 5, is the second case study investigated in this thesis. Genetic algorithms were applied to this problem as part of a EUCLID (European Cooperation for the Long Term in Defence) funded multi-national study to compare exact and heuristic techniques for hard combinatorial problems associated with military applications. A number of approaches used to solve this highly constrained, hard problem for genetic algorithms are described. These include a range of new genetic operators and catalytic terms that are added to the fitness function. Apart from the direct approach to solving this problem using genetic algorithms, for which the majority of operators and catalytic terms apply, an indirect approach which combines genetic algorithms with backtracking is described. The possibility of using a meta genetic algorithm to chose the best of a multitude of options, e.g. genetic operators and parameter settings for a GA applied to the Radio Link Frequency Assignment Problem is investigated. Results are reported for two sets of problems that were used by all participants in this project. An overview of the techniques investigated for this project is given and the chapter concludes with comparisons between all these techniques. In Chapter 6, an overview of general aspects in parallel processing is given. Parallel computer architectures, parallel programming paradigms and performance measurement are the main subjects dealt with in this chapter. Special emphasis is given to material relevant to the investigation on parallel genetic algorithms, presented in the following chapter. In Chapter 7, parallel genetic algorithms are examined in some detail. A number of parallel GA models are described and classified according to whether they are designed around the sequential GA or around a more natural model. A ParallelSequential General Search paradigm is presented that unifies the various parallel models and is used to extend the GA toolkit into a parallel GA toolkit for a parallel system based on Transputers. The parallel GA models are applied to problems from both of the case studies considered in this thesis. A comparison between the various parallel GA models concludes this chapter. The thesis finishes with a summary of a number of conclusions drawn from this research together with some suggestions for how this work may be continued in the future.

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Radio Frequency Identification (RFID) is an emerging area under ubiquitous computing. RFID benefits include multiple read/write, longer read range and no requirement for line of sight. Due to security and privacy issues, RFID is not as popular as it should be. Tag cloning is one of the biggest threats to RFID systems. Easy access to RFID tags allows an attacker to replicate the tags and insert duplicate tags into the system. An RFID tag cloning attack can lead to access control or financial frauds in areas like supply chain management and government issued IDs. In this thesis, a cloning prevention protocol is proposed. It uses light weight functions such as Pseudo Random Number Generator (PRNG) and compare function. A 3-way handshake with a secret key, frequency hopping mechanism and dynamic fake ID makes this protocol a secure authentication mechanism.

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