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An active sensor network is a wireless network comprising a large number of mobile sensor nodes. This dissertation deals with a general model of active sensor network, heterogeneous sensor network, where sensor nodes may have different sensing ranges. The deployment problem aims at relocating a large set of sensor nodes from arbitrary locations to give a connected, hole-free and locally maximized sensing coverage of the entire network., The major contribution of this dissertation lies in four aspects. First, it is the first work that solves the deployment problem for optimal deterministic coverage of heterogeneous sensor networks, while most existing works limit their problems on stochastic coverage and homogeneous sensing model. Second, this work envisages the use of a generalized Voronoi diagram, the power diagram, as a novel solution to geometrically analyse and visualise the coverage of a heterogeneous sensor network. Third, it an original work that applies circle packing on sensor network deployment, and analyses and proves a number of geometrical properties of circle packing. Fourth, all methods provided in this dissertation are based on localized and distributed computation; no centralized processor or common data fusion platform is assumed to exist., This dissertation gives an algorithm to solve the self-deployment problem. It is composed three parts. In the first part, the logical topology of the sensor network is constructed as triangulation by three distributed protocols: localized Delaunay triangulation, redundant boundary edge pruning and local edge swapping. Second, the sensor nodes self-deploy to new locations that are calculated using a circle packing algorithm. The dissertation shows that the homomorphism between Voronoi and power diagrams is necessary and sufficient for the equivalences of power Delaunay triangles to Delaunay triangles. This result allows the network to preserve a unit Delaunay triangulation by localized re-triangulations among a small number of nodes. Third, the sensor nodes further relocate themselves based on a virtual force approach to eliminate all existing coverage holes and redundant overlaps., This dissertation studies the problem of active sensor network deployment. It focuses on self-deployment, localized and distributed computation and coverage maximization of heterogeneous sensor networks., Lam, Miu Ling., "February 2008.", Adviser: Yun-hui Liu., Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1757., Thesis (Ph.D.)--Chinese University of Hong Kong, 2008., Includes bibliographical references (p. 152-158)., 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., s in English and Chinese., School code: 1307., isbn: 9781109048971, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

by Lam Miu-Ling., Thesis (M.Phil.)--Chinese University of Hong Kong, 2002., Includes bibliographical references (leaves 64-67)., s in English and Chinese., Chapter Chapter 1. --- Introduction --- p.1, Chapter Chapter 2. --- Mathematical Preliminaries and Problem Definition --- p.6, Chapter 2.1 --- Grasp Synthesis in Discrete Domain, Chapter 2.2 --- Assumptions, Chapter 2.3 --- Frictionless Form-Closure Grasp, Chapter 2.4 --- Frictional Form-Closure Grasp, Chapter 2.5 --- Problem Definition, Chapter Chapter 3. --- A Qualitative Test Algorithm and a Local Search Algorithm --- p.18, Chapter 3.1 --- A Qualitative Test Algorithm, Chapter 3.2 --- A Local Search Algorithm, Chapter 3.3 --- Grasp Planning under Kinematic Constraints, Chapter Chapter 4. --- A Divide-and-Conquer Technique --- p.29, Chapter 4.1. --- Determining a Separating Hyperplane, Chapter 4.2. --- Divide-and-Conquer in Frictionless Case, Chapter 4.3. --- Divide-and-Conquer in Frictional Case, Chapter Chapter 5. --- Implementation and Examples --- p.40, Chapter 6.1. --- Examples of Frictionless Grasps, Chapter 6.2. --- Examples of Frictional Grasps, Chapter 6.3. --- Examples of Grasps under Kinematic Constraints, Chapter Chapter 6. --- Conclusions --- p.62, Bibliography --- p.64, http://library.cuhk.edu.hk/record=b5891098, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

by Lam Miu-ling, Theresa., Thesis (M.A.Ed.)--Chinese University of Hong Kong, 1991., Bibliography: leaves 95-110., ACKNOWLEDGEMENTS --- p.i, p.iii, LIST OF TABLES --- p.vii, LIST OF FIGURES --- p.ix, CHAPTER, Chapter I. --- INTRODUCTION --- p.1, Nature of the problem --- p.1, Purpose of the study --- p.6, Significance of the study --- p.7, Chapter II. --- REVIEW OF LITERATURE --- p.9, Job stress --- p.9, Theory of P-E fit --- p.14, Individual needs --- p.17, Job demands --- p.20, Job future ambiguity --- p.22, Stress and strain --- p.27, Social support --- p.30, Chapter III. --- FRAMEWORK OF STUDY --- p.39, Chapter IV. --- METHODOLOGY --- p.44, Statement of hypotheses --- p.44, Instrumentation --- p.45, Definition of variables --- p.52, Sampling design --- p.53, Research procedures --- p.54, Statistical procedures --- p.55, Limitations --- p.57, Chapter V. --- RESULTS --- p.59, Results of pilot study --- p.59, Results of main study --- p.60, Reliability of instruments --- p.60, Factor analysis of strain measures --- p.61, Descriptive statistics of variables --- p.62, Statistical analysis --- p.67, Chapter VI. --- DISCUSSION OF FINDINGS --- p.79, Teacher background characteristics and job strain --- p.79, Job stress and job strain --- p.81, Social support and job stress --- p.83, Social support and job strain --- p.85, Buffering effects of social support --- p.86, Chapter VII. --- CONCLUSIONS AND RECOMMENDATIONS --- p.88, Conclusions --- p.88, Recommendations --- p.89, Recommendations for school authority --- p.90, Recommendations for teachers organizations --- p.91, Recommendations for the Education Department --- p.92, Recommendations for future research --- p.92, REFERENCES --- p.95, APPENDIX, http://library.cuhk.edu.hk/record=b5886936, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)