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Kong Chun Wai. / Thesis submitted in: July 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 53-54). / Abstracts in English and Chinese. / Contents / acknowledgement --- p.I / Abstract --- p.II / 摘要 --- p.III / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Related Works --- p.4 / Chapter 2.1 --- Previous Work --- p.4 / Chapter 2.2 --- Comparison --- p.5 / Chapter Chapter 3 --- System Architecture --- p.7 / Chapter 3.1 --- Transmission Scheduling --- p.7 / Chapter 3.2 --- Admission Control --- p.9 / Chapter 3.3 --- Challenges in Supporting VBR-encoded Video --- p.10 / Chapter Chapter 4 --- Priority Scheduling --- p.12 / Chapter 4.1 --- Static Channel Priority (SCP) --- p.13 / Chapter 4.2 --- Dynamic Channel Priority (DCP) --- p.16 / Chapter Chapter 5 --- Turbo-Slice-and-Patch --- p.19 / Chapter 5.1 --- Video Pre-processing --- p.19 / Chapter 5.2 --- Bandwidth Allocation --- p.22 / Chapter 5.3 --- Three-Phase Patching --- p.23 / Chapter 5.4 --- Client Buffer Requirement --- p.27 / Chapter Chapter 6 --- Playback Continuity --- p.30 / Chapter Chapter 7 --- Performance Evaluation --- p.39 / Chapter 7.1 --- Average Latency --- p.40 / Chapter 7.2 --- Client Buffer Requirement --- p.43 / Chapter 7.3 --- Choice of Parameter Rcut --- p.44 / Chapter 7.4 --- Latency versus Arrival Rate --- p.46 / Chapter 7.5 --- Server Bandwidth Comparison --- p.48 / Chapter 7.6 --- Bandwidth Partitioning --- p.50 / Chapter Chapter 8 --- Conclusions --- p.52 / Bibliography --- p.53

Wong Ying Wai. / Thesis submitted in: December 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 64-66). / Abstracts in English and Chinese. / Acknowledgement --- p.I / Abstract --- p.II / 摘要 --- p.III / Chapter Part I - --- Recursive Patching --- p.1 / Chapter Chapter 1 --- Introduction --- p.2 / Chapter Chapter 2 --- Transition Patching --- p.5 / Chapter Chapter 3 --- Recursive Patching --- p.9 / Chapter Chapter 4 --- Stream Assignment --- p.12 / Chapter 4.1 --- The Equal-Split Stream Assignment Scheme --- p.12 / Chapter 4.2 --- A Hierarchical Equal-Split Stream Assignment Scheme --- p.14 / Chapter Chapter 5 --- Performance Evaluation --- p.16 / Chapter Chapter 6 --- Conclusion --- p.18 / Bibliography --- p.19 / Chapter Part II - --- Interactive Multicast Video Streaming --- p.21 / Chapter Chapter 1 --- Introduction --- p.22 / Chapter Chapter 2 --- Background --- p.25 / Chapter 2.1 --- Multicast Streaming Algorithms --- p.25 / Chapter 2.2 --- Interactive Playback Support --- p.30 / Chapter Chapter 3 --- Interactive Multicast Streaming --- p.34 / Chapter 3.1 --- Interactivity Model --- p.34 / Chapter 3.2 --- Request Scheduling --- p.36 / Chapter 3.3 --- Client Buffer Management --- p.37 / Chapter 3.4 --- Performance Impact --- p.39 / Chapter Chapter 4 --- Static Full Stream Scheduling --- p.45 / Chapter Chapter 5 --- Adaptive Full Stream Scheduling --- p.48 / Chapter Chapter 6 --- Performance Evaluation --- p.52 / Chapter 6.1 --- Optimization of the Full Stream Threshold --- p.52 / Chapter 6.2 --- Latencies Comparisons --- p.57 / Chapter 6.3 --- Effect of Client Buffer Constraint --- p.58 / Chapter 6.4 --- Just-in-Time Simulation --- p.60 / Chapter Chapter 7 --- Conclusion --- p.63 / Bibliography --- p.64

Submitted by Cátia Araújo (catia.araujo@unipampa.edu.br) on 2017-01-24T13:19:49Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Estudo de antenas de microfita com dupla-banda e dupla-polarização para aplicação em redes retro-diretivas.pdf: 5490330 bytes, checksum: db372388acb59d1f9f94845c1ffc044e (MD5) / Approved for entry into archive by Cátia Araújo (catia.araujo@unipampa.edu.br) on 2017-01-24T13:22:19Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Estudo de antenas de microfita com dupla-banda e dupla-polarização para aplicação em redes retro-diretivas.pdf: 5490330 bytes, checksum: db372388acb59d1f9f94845c1ffc044e (MD5) / Made available in DSpace on 2017-01-24T13:22:19Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Estudo de antenas de microfita com dupla-banda e dupla-polarização para aplicação em redes retro-diretivas.pdf: 5490330 bytes, checksum: db372388acb59d1f9f94845c1ffc044e (MD5) Previous issue date: 2015-11-13 / O presente trabalho apresenta o desenvolvimento de uma antena dupla-faixa e com dupla-polarização para instalação em plataformas de alta altitude (do inglês, HAPs – High-Altitude Platforms). Como principal contribuição científica, o objetivo foi a obtenção de um irradiador com as características acima citadas e com duas portas, uma para cada banda de operação, altamente isoladas. A antena foi desenvolvida em tecnologia de microfita e pode ser utilizada para a composição de uma rede de antenas retro-diretiva. Dada a alta isolação obtida entre as portas, pode-se utilizar o irradiador desenvolvido simultaneamente nos modos de recepção (em 5,8 GHz) e transmissão (em 7,0 GHz). Esta antena caracteriza-se como contribuição original desta dissertação. Diferentes técnicas que possibilitam a obtenção de característica dupla-faixa e dupla-polarização para antenas construídas em tecnologia de microfita são estudadas, especificamente voltadas para aplicações em redes retro-diretivas. As faixas de interesse encontram-se no intervalo de 5,75 GHz a 5,85 GHz para a banda inferior e 6,95 GHz a 7,05 GHz para a banda superior. Além de atender às especificações técnicas nas faixas de frequência especificadas, os requisitos de bom coeficiente de reflexão, polarização circular, ganho e impedância de entrada devem ser devidamente satisfeitos. Primeiramente, visando a obter uma geometria para compor uma rede de antenas retro-diretivas, quatro estruturas com característica de dupla-banda e dupla-polarização são estudadas. Os princípios de funcionamento e particularidades de cada geometria estão detalhadamente descritos ao longo do trabalho. Os resultados preliminares de duas das quatro geometrias de antenas são apresentados através de simulação com os pacotes Ansoft Designer® e ANSYS HFSSTM. Foram levantados e estudados os parâmetros elétricos de cada irradiador em função da variação de suas dimensões físicas. Finalmente, dentre as antenas analisadas foi realizada a construção de duas geometrias com a finalidade de validar experimentalmente suas características de irradiação. Os resultados numéricos e experimentais obtidos permitem afirmar que uma das geometrias construídas é capaz de operar em duas bandas e também com polarização circular à direita e à esquerda nas bandas inferior e superior, respectivamente. / This work presents the development of a dual-band and dual-polarized antenna for installation in High-Altitude Platform Station (HAPs). As the main scientific contribution, the objective was to obtain a radiator with the above mentioned features and with two ports with high isolation between then, whereby one port should be used for one operating band. The antenna is designed in microstrip technology and can be used to compose a retrodirective antenna array. With the high isolation achieved between the two ports, the developed radiator can be used simultaneously in the receiving (at 5.8 GHz) and transmitting modes (at 7 GHz). This antenna is an original contribution of this dissertation. Different techniques that allow obtaining the dual-band and dual-polarization characteristics for antennas implemented in microstrip technology are studied, especially those suitable for application in retrodirective arrays. The bands of interest are in the range of 5.75 GHz to 5.85 GHz for the lower band and 6.95 GHz to 7.05 GHz for the upper band. In addition to meeting the technical specifications in this frequency bands, the requirements of good reflection coefficient, circular polarization, gain and input impedance must be satisfied. Firstly, in order to obtain a geometry to compose a retrodirective antenna array, four structures with dual-band and dual-polarization characteristics are studied. The operating principles and the main features of each geometry are described in detail along the work. Preliminary results for two of them are presented through simulation packages Ansoft Designer® e ANSYS HFSSTM. The electrical parameters of each radiator have been studied by means of parametric simulations of its physical dimensions. Finally, among the analyzed antennas, two geometries were prototyped in order to validate experimentally their radiation properties. The numerical and experimental results validate that one of built geometries can be operate in the two bands and with RHCP and LHCP in the lower and higher bands, respectively.

This study applies a test for subadditivity (natural monopoly) to Australian telecommunications industry data for the period 1954 to 1990. If an industry exhibits subadditive cost, a monopoly can provide total industry output at a lower cost than multiple firms. The test for subadditivity is dependent on econometric estimation of a theoretically valid cost function. The cost function employed in this study is a multiple output variation of the symmetric generalised McFadden cost function. The main advantage of this specification is the ability to impose concavity on the cost function with respect to the input prices without imposing a priori restrictions on the input substitution elasticities.While there have been numerous previous subadditivity studies, this study is novel in two respects. First, this study contains the results of a direct test involving the provision of data carriage services provided by Australias monopoly carrier from 1970 to 1990. Thus, the test for subadditivity is applied to a relatively new service at a time when demand is in its infancy. Second, the approach to modelling makes explicit allowance for radical technological changes and lags in adjustment.The results indicate cost complementarity between data-aggregate output and large economies of scale. However, these effects are not strong enough to guarantee subadditivity. Analysis suggests that the most likely cause of subadditivity is the extent of network duplication between competitors. Evidence of subadditivity is found for firms that duplicate more than 30% of the networks fixed cost. This implies that at the national level, competition policy is the right choice. This suggests that regulated competition is likely to be no more costly than monopoly.

This study explores how governments use knowledge to inform telecommunications policy-making and policy-implementation in regional development. It focuses on epistemological aspects and assumptions made within the parameters of Enlightenment thinking or the Newtonian paradigm, also known as the classical scientit1c paradigm. It argues that lmowledge formed within this paradigm, usually generated at a distance, has been individ,uated, detached, segmented and abstracted. 'Individuation' focuses on individuals and things rather than communities and processes. 'Detachment' separates the subjective mind from the objective environment to produce reliable information. 'Segmentation' produces validity of information by parsing the objective environment from its social and historical context. 'Abstraction' allows objectivity and systematisation of information. When used to inform policy, such knowledge creates a narrow 'standardising gaze' that 'disciplines' communities to conform to dominant social behaviour and beliefs. Case studies are used to demonstrate that the two major models of development, as products ofthis paradigm, employ this gaze rendering replicability difficult ifnot impossible. These models are the top-down and bottom-up approach that are epitomised by the Silicon Valley model and telecentre moveluent respectively. How this gaze inhibits/facilitates development in policy implementation is then examined in the Goldfields Esperance region in Western Australia. An holistic approach using cotnplex adaptive systems is used to understand the multidisciplinary aspects involved in development. This is combined with action research, a reflexive methodology. Action research has the ability to access local knowledge to provide data and evaluation in situ rather than on a post hoc basis. The findings demonstrate that complex systems analysis and action research provide a modus operandi that: a) recognises the interplay of various factors (such as power relations, economic cycle, social and political institutions) at different levels of the system; b) recognises time, context and path-dependence of regional development; c) provides a filter that minimises the 'standardising gaze' and d) gives an access to knowledge and insight to local issues, which can facilitate policy implementation of development that is sympathetic to regional communities.

This study was conducted in the context of health service planning in an environment of changing government strategies for regional, rural and remote area health care and telecommunications infrastructure planning in Western Australia. The study provides an account of the State Government of Western Australia’s planning for the implementation of a telecommunications network infrastructure, and specifically the Telehealth Project, conducted between 1998 and 2002. The purpose of this study was to examine influences on community participation in planning within the dynamic political, economic and social forces that impact on the development of regional, rural and remote area health services. Specifically, the study outlines the issues and barriers in providing for significant local participation in projects that are centrally initiated and controlled. It examines the influences in planning for projects that incorporate local community based beliefs and needs, the requirements of collaborating with multiple state and national government departments, and the private sector. This study was situated within the interpretive paradigm, and is conceptualised within Donabedian’s (1969) framework for assessing and assuring quality in health care. The methodological approach is bound within a case study and consists of a participatory action research approach. The research method uses the single case to undertake in-depth interviews, observations and a survey to collect data from community, government and industry members as a basis for reflection and action. The findings of the study clearly indicated that there was consensus between all rural, remote and metropolitan area participants that telecommunications did offer the opportunity to provide increased, improved or alternative health services. However, there were a number of obstacles to the success of the planning process, including a lack of local community inclusion in planning committees, poor communication within central government agencies, overuse of external consultants, a bias toward the medical view, a limited scope of invitation to contribute, and local information being overlooked in the final implementation plan. Analysis of planning for the Telehealth Project reveals the implications of organisational and political stakeholders making final decisions about outcomes; and provides a reminder of the importance of engaging communities authentically when planning for health and telecommunications services which involve the public and private sectors. The originality and significance of this study stems from understanding how technology can advance community health; through measures such as the use of community participation strategies, through authentic community based leadership, truly representative participants, decentralised decision making, a focus on community based health needs and change management strategies that include all of these. Consequently, the study advances knowledge of community participation in planning, and the evidence suggests implications for practice, education and further research.

The study examines the development of telecommunications and its impacts on Chinese economic growth since telecommunications has been undergoing dramatic reforms in the 1980s. On November 2001, China was officially the WTO member to open the market for foreign investors. It is obvious that the telecommunications infrastructure development can play a key role in economic growth in China. Furthermore, China has become the world’s single largest telecommunications market since 2002. In this research, I present evidence that it empirically not only investigates the telecommunications development and its impacts on economic growth, but also tests their relationship with initial economic condition, fixed investment, population growth, foreign direct investment as well as telecommunications infrastructure development using the panel data approach with a dynamic fixed effect model for the span of time from 2003 to 2008. I find that that mobile phone user density to be the new proxy for telecommunications infrastructure in China contributes in a major way to the economic growth. It means that mobile communication systems do have positive impact and effect on the regional economy of China. It is a crucial determinant as findings indicate a significant and positive correlation between telecommunications development and regional growth in China, after controlling for a number of other factors. Results also show that investment in telecommunications is subject to diminishing returns.

This thesis aims at both developing highly nonlinear Aluminum Gallium Arsenide waveguides(AlGaAs) and demonstrating all-optical wavelength conversion via cross-phase modulation in AlGaAs waveguides at telecommunications wavelengths. This work covers waveguide design, device fabrication, device characterization and system work.

This thesis aims at both developing highly nonlinear Aluminum Gallium Arsenide waveguides(AlGaAs) and demonstrating all-optical wavelength conversion via cross-phase modulation in AlGaAs waveguides at telecommunications wavelengths. This work covers waveguide design, device fabrication, device characterization and system work.