Thesis (Ph. D.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.

This thesis addresses two of the main issues required to build reliable terabit ATM networks. A high-capacity switch and an efficient error recovery protocol are the key elements in building a reliable terabit ATM network. In this thesis, a terabit switch architecture and a reliable end-to-end error recovery protocol for terabit networks are introduced. The proposed terabit ATM switch architecture is designed to work efficiently in low-capacity and high-capacity environments. The architecture is developed by interconnecting small-capacity switching modules in a scalable fashion. The switching module can be used alone as a small-capacity ATM switch. Multiple the switching modules can be used to achieve any required switching capacity. The proposed interconnecting scheme provides remarkable low cell-delay characteristics with a simple distributed cell scheduler. The proposed architecture has a high reliability: Even when a complete switching module fails the switch will continue to work efficiently. The switching element which is introduced as the main building block for the terabit switch architecture is a nonblocking input buffer ATM switch. The input buffers are implemented as groups of parallel shift-registers. The parallel nature of the storing buffers overcomes the Head Of Line and low throughput problems of existing input buffer switch architectures. In addition, using the shift registers overcomes the need for serial-to-parallel and parallel-to-serial format conversions. ATM networks support different types of services having different delay and loss requirements. A priority scheduling scheme is proposed to facilitate the support of different Qualities of Service. The proposed scheme satisfies both real-time and non-real-time service requirements. Cell loss is not acceptable for some data applications. This thesis proposes an efficient error recovery protocol which guarantees reliable communication with limited overhead. The proposed protocol requires a low number of control packets to achieve reliable communication. It also adapts itself, in order to work efficiently during both congested and non congested states. / Graduate

<p>This dissertation investigates the strategic implications of blockchain technologies on interorganizational collaborations. Recently, blockchain technology has been permeating a broad range of industries and impacting how organizations conduct business. Rather than a traditional industrial technology that boosts productivity, blockchain should be viewed as an institutional technology that influences collaborative relationships among business agents. This dissertation endeavors to (partially) answer the overarching question that, from the point of view of cooperative strategies, what are the implications of blockchain technology for those involved organizations?</p> <p>One of the major theoretical arguments of this dissertation is that blockchain technology offers a new way of organizing collaborations. It works as a governance mechanism that is different from traditional social mechanisms—contractual and relational governance. Specifically, it provides a unique approach to enforcing agreements automatically through codes and algorithms. It also differs from other information technologies, such as EDI, in terms of the capacity to enforce agreements and govern collaborations. Furthermore, it acknowledges that blockchain governance has its limits – it can only efficiently organize explicit collaborations while is less efficient on tacit ones. Nevertheless, understanding the new governance logic with blockchain technology has important implications for managers in choosing the right strategic tool to organize collaborative efforts with other organizations.</p> <p>The new organizing approach by blockchain technology also enhances the scalability of governance and enables an increasing number of multiparty collaborations. By reviewing the alliance literature, this dissertation suggests that multiparty collaborations have unique features that deserve separate scholarly attention from well-studied dyadic alliances. Focusing on the increased number of collaborators with blockchain technology, this dissertation investigates the performance heterogeneity of blockchain consortia and its determinants. It challenges the conventional view in the multiparty alliance literature that the number of firms negatively impacts alliance performance. By differentiating between short-term and long-term performance of blockchain consortia, it argues that the compositional characteristics of each blockchain consortium’s founding group have an impact on its performance. Empirical results from a sample of blockchain consortia show that, although the size of the founding group is negatively related to consortium performance in the short term (in terms of the speed to complete piloting), it is positively associated with performance in the longer run (in terms of survival and growth). Specifically, the long-term performance effect is explained by the composition of the founding group, in terms of the diversity of industry sectors and the number of competing ties. The findings have direct implications for scholars and managers in understanding the strategic trade-offs of leveraging the business potentials of blockchain technology.</p>

published_or_final_version / abstract / Computer Science / Doctoral / Doctor of Philosophy

Este trabalho busca compreender as amarras e as potencialidades em torno do uso das mídias digitais por ativistas autônomos anticapitalistas. O objetivo é partir da discussão sobre a potência democratizante que a Internet ativa e chegar à análise de coletivos autônomos que produzem e divulgam no espaço digital um discurso anticapitalista. Embora as novas mídias façam parte da indústria na qual a informação é mercadoria e meio de reprodução da lógica de produção vigente, a existência de grupos que usufruem das mídias digitais para criticar o atual modelo político, econômico e social contribui para o crescimento descentralizado da construção e difusão do pensamento antissistêmico. Portanto, interessa a esta pesquisa refletir sobre as origens desse ativismo e seu potencial de transformação social. A narração de episódios recentes da trajetória do movimento autônomo - o levante zapatista, a Ação Global dos Povos e as ocupações de 2011- vai ajudar na compreensão de elementos encontrados nos protestos de junho de 2013 e na formação de uma rede de coletivos em espaços físicos e virtuais. A coleta de dados de redes sociais e entrevistas com militantes basearão a descrição das ações comunicativas empreendidas por esses ativistas. / This paper seeks to understand the limits and potentialities surrounding the use of digital media by autonome anticapitalist activists. The purpose is to depart from the discussion about the democratizing potency that Internet activates and reach the analysis of autonome movements that produce and publish in the digital environment an anticapitalist speech. Although new media takes part of industry where information is merchandise and way of reproducing the logic of the current production, the existence of groups that take advantage of digital media to criticize the current political, economic and social model contributes to the decentralized growth of construction and dissemination of antisystemic thought. Therefore, this research is interested in reflect on the origins of this activism and its potential for social transformation. The narration of recent episodes of the trajectory of the autonomous movement - the Zapatista insurrection, the People\'s Global Action and occupations in 2011 - will help in the understanding of elements found in the protests of June 2013 and the formation of a network of collectives in physical and virtual spaces. The collection of data from social networks and interviews with militants will base the description of communicative actions undertaken by these activists.

by Lau Chu Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 76-83). / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Basic Notions --- p.13 / Chapter 3 --- Fast Knockout --- p.19 / Chapter 3.1 --- The Algorithm of Fast Knockout --- p.20 / Chapter 3.2 --- Complexity of the Fast Knockout Algorithm --- p.29 / Chapter 3.3 --- Summary --- p.35 / Chapter 4 --- k-Sortout --- p.36 / Chapter 4.1 --- A Brief Review of k-Sorting --- p.37 / Chapter 4.2 --- The Algorithm of k-Sortout --- p.47 / Chapter 4.3 --- Complexity of the k- Sortout Algorithm --- p.53 / Chapter 4.4 --- Summary --- p.58 / Chapter 5 --- General Sortout --- p.59 / Chapter 5.1 --- The General Algorithm of Sortout --- p.59 / Chapter 5.2 --- Complexity of Concentrators by the General Algorithm --- p.64 / Chapter 5.3 --- Summary --- p.69 / Chapter 6 --- Concluding Remarks --- p.70 / Chapter 6.1 --- Summary of Results --- p.70 / Chapter 6.2 --- Directions for Further Research --- p.73 / Bibliography --- p.76

by Chi-yin Tse. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 118-[121]). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Video Compression and Transport --- p.2 / Chapter 1.2 --- VBR-CBR Adaptation of Video Traffic --- p.5 / Chapter 1.3 --- Research Contributions --- p.7 / Chapter 1.3.1 --- Spatial Smoothing: Video Aggregation --- p.8 / Chapter 1.3.2 --- Temporal Smoothing: A Control-Theoretic Study。 --- p.8 / Chapter 1.4 --- Organization of Thesis --- p.9 / Chapter 2 --- Preliminaries --- p.13 / Chapter 2.1 --- MPEG Compression Scheme --- p.13 / Chapter 2.2 --- Problems of Transmitting MPEG Video --- p.17 / Chapter 2.3 --- Two-layer Coding and Transport Strategy --- p.19 / Chapter 2.3.1 --- Framework of MPEG-based Layering --- p.19 / Chapter 2.3.2 --- Transmission of GS and ES --- p.20 / Chapter 2.3.3 --- Problems of Two-layer Video Transmission --- p.20 / Chapter 3 --- Video Aggregation --- p.24 / Chapter 3.1 --- Motivation and Basic Concept of Video Aggregation --- p.25 / Chapter 3.1.1 --- Description of Video Aggregation --- p.28 / Chapter 3.2 --- MPEG Video Aggregation System --- p.29 / Chapter 3.2.1 --- Shortcomings of the MPEG Video Bundle Scenario with Two-Layer Coding and Cell-Level Multiplexing --- p.29 / Chapter 3.2.2 --- MPEG Video Aggregation --- p.31 / Chapter 3.2.3 --- MPEG Video Aggregation System Architecture --- p.33 / Chapter 3.3 --- Variations of MPEG Video Aggregation System --- p.35 / Chapter 3.4 --- Experimental Results --- p.38 / Chapter 3.4.1 --- Comparison of Video Aggregation and Cell-level Multi- plexing --- p.40 / Chapter 3.4.2 --- Varying Amount of the Allocated Bandwidth --- p.48 / Chapter 3.4.3 --- Varying Number of Sequences --- p.50 / Chapter 3.5 --- Conclusion --- p.53 / Chapter 3.6 --- Appendix: Alternative Implementation of MPEG Video Aggre- gation --- p.53 / Chapter 3.6.1 --- Profile Approach --- p.54 / Chapter 3.6.2 --- Bit-Plane Approach --- p.54 / Chapter 4 --- A Control-Theoretic Study of Video Traffic Adaptation --- p.58 / Chapter 4.1 --- Review of Previous Adaptation Schemes --- p.60 / Chapter 4.1.1 --- A Generic Model for Adaptation Scheme --- p.60 / Chapter 4.1.2 --- Objectives of Adaptation Controller --- p.61 / Chapter 4.2 --- Motivation for Control-Theoretic Study --- p.64 / Chapter 4.3 --- Linear Feedback Controller Model --- p.64 / Chapter 4.3.1 --- Encoder Model --- p.65 / Chapter 4.3.2 --- Adaptation Controller Model --- p.69 / Chapter 4.4 --- Analysis --- p.72 / Chapter 4.4.1 --- Stability --- p.73 / Chapter 4.4.2 --- Robustness against Coding-mode Switching --- p.83 / Chapter 4.4.3 --- Unit-Step Responses and Unit-Sample Responses --- p.84 / Chapter 4.5 --- Implementation --- p.91 / Chapter 4.6 --- Experimental Results --- p.95 / Chapter 4.6.1 --- Overall Performance of the Adaptation Scheme --- p.97 / Chapter 4.6.2 --- Weak-Control verus Strong-Control --- p.99 / Chapter 4.6.3 --- Varying Amount of Reserved Bandwidth --- p.101 / Chapter 4.7 --- Conclusion --- p.103 / Chapter 4.8 --- Appendix I: Further Research --- p.103 / Chapter 4.9 --- Appendix II: Review of Previous Adaptation Schemes --- p.106 / Chapter 4.9.1 --- Watanabe. et. al.'s Scheme --- p.106 / Chapter 4.9.2 --- MPEG's Scheme --- p.107 / Chapter 4.9.3 --- Lee et.al.'s Modification --- p.109 / Chapter 4.9.4 --- Chen's Adaptation Scheme --- p.110 / Chapter 5 --- Conclusion --- p.116 / Bibliography --- p.118

by Kit-man Chan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 82-86). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview of Integrated Service Digital Networks --- p.1 / Chapter 1.2 --- Multirate Loss Networks --- p.5 / Chapter 1.3 --- Previous Work --- p.7 / Chapter 1.4 --- Organization --- p.11 / Chapter 1.5 --- Publications --- p.12 / Chapter 2 --- Call Admission in Multirate Loss Networks --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Two Adaptive Routing Rules --- p.15 / Chapter 2.3 --- Call Admission Policies --- p.17 / Chapter 2.4 --- Analysis of Call Admission Policies --- p.25 / Chapter 2.4.1 --- "The CS, LO, GB and the EB Policies" --- p.25 / Chapter 2.4.2 --- The DP Policy --- p.29 / Chapter 2.5 --- Performance Comparisons --- p.32 / Chapter 2.6 --- Concluding Remarks --- p.35 / Chapter 3 --- Least Congestion Routing in Multirate Loss Networks --- p.41 / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- The M2 and MTB Routings --- p.42 / Chapter 3.2.1 --- M2 Routing --- p.43 / Chapter 3.2.2 --- MTB Routing --- p.43 / Chapter 3.3 --- Bandwidth Sharing Policies and State Aggregation --- p.45 / Chapter 3.4 --- Analysis of M2 Routing --- p.47 / Chapter 3.5 --- Analysis of MTB Routing --- p.50 / Chapter 3.6 --- Numerical Results and Discussions --- p.53 / Chapter 3.7 --- Concluding Remarks --- p.56 / Chapter 4 --- The Least Congestion Routing in WDM Lightwave Networks --- p.60 / Chapter 4.1 --- Introduction --- p.60 / Chapter 4.2 --- Architecture and Some Design Issues --- p.62 / Chapter 4.3 --- The Routing Rule --- p.66 / Chapter 4.4 --- Analysis of the LC Routing Rule --- p.67 / Chapter 4.4.1 --- Fixed Point Model --- p.67 / Chapter 4.4.2 --- Without Direct-link Priority --- p.68 / Chapter 4.4.3 --- With Direct-link Priority --- p.72 / Chapter 4.5 --- Performance Comparisons --- p.73 / Chapter 4.6 --- Concluding Remarks --- p.75 / Chapter 5 --- Conclusions and Future Work --- p.79 / Chapter 5.1 --- Future Work --- p.80

by Shum Kam Hong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 125-131). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Outline of the thesis --- p.6 / Chapter 1.3 --- Current Art in Packet Switching --- p.9 / Chapter 2 --- Management of Control Information --- p.17 / Chapter 2.1 --- Inter-node Exchange of Link Congestion Status --- p.21 / Chapter 2.2 --- Consistency of Control Information --- p.24 / Chapter 2.3 --- Alternate Format of Control Information --- p.26 / Chapter 3 --- Traffic Flow Control --- p.29 / Chapter 3.1 --- Control of Traffic Influx into the Network --- p.29 / Chapter 3.2 --- Control of Traffic Loading from the Node --- p.30 / Chapter 3.3 --- Flow Control for Connection Oriented Traffic --- p.32 / Chapter 3.4 --- Judgement of Link Status --- p.38 / Chapter 3.5 --- Starvation-free and Deadlock-free --- p.42 / Chapter 4 --- Call Set-up Algorithm Traffic Modelling --- p.47 / Chapter 4.1 --- Basic Algorithm --- p.47 / Chapter 4.2 --- Minimization of Bandwidth Overhead --- p.48 / Chapter 4.3 --- Two-way Transmission --- p.51 / Chapter 4.4 --- Traffic Modelling --- p.52 / Chapter 4.4.1 --- Aggregate Traffic Models --- p.53 / Chapter 4.4.2 --- Traffic Burstiness --- p.57 / Chapter 5 --- Parameters Tuning and Analysis --- p.76 / Chapter 5.1 --- Scheme I : Scout Pumping --- p.76 / Chapter 5.2 --- Scheme II : Speed-up Scout Pumping --- p.85 / Chapter 5.3 --- Blocking Probability --- p.90 / Chapter 5.4 --- Scout Stream Collision --- p.92 / Chapter 6 --- Simulation Modelling & Performance Evaluation --- p.96 / Chapter 6.1 --- The Network Simulator --- p.96 / Chapter 6.1.1 --- Simulation Event Scheduling --- p.97 / Chapter 6.1.2 --- Input Traffic Regulation --- p.100 / Chapter 6.1.3 --- Actual Offered Load --- p.101 / Chapter 6.1.4 --- Static and Dynamic Parameters --- p.103 / Chapter 6.2 --- Simulation Results --- p.107 / Chapter 7 --- Conclusions --- p.123 / Chapter A --- List of Symbols --- p.132

Wong, Po-Choi. / Summary in Chinese. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 156-164.