The mechanisms of strata deformation due to underground mining were analyzed in an effort to better understand immediate roof behavior and surface displacements. Strata deformation characteristics above longwall and room-and-pillar mines in the eastern U.S. coalfields were evaluated and a numerical procedure was developed for calculating surface displacements. The model, based on the well-known finite element method, utilized empirical indices associated with subsidence engineering in order to incorporate the site-specific characteristics into the formulation. Different material behavior models and failure criteria were employed in an attempt to determine the areas highly deformed by underground excavation. Additionally, the method was sensitive to the ratios of the elastic moduli used to describe different rocks and/ or rock conditions, and not to the magnitude of the elastic properties. Thus, the use of arbitrary reduction factors to convert laboratory to in situ property values was completely avoided and scaling of the calculated surface displacements was based on, the empirically predicted, regional or local parameters. The use of fixed displacement nodes around an opening to induce failure overcame the roof-floor overlap problem encountered in other formulations. The successful implementation of the proposed methodology for modeling surface deformations complements and enhances existing prediction techniques, which are primarily based on empirical approaches, by allowing parametric analysis for different excavation geometrics, roof convergence curves and overburden properties. / Ph. D.

Cheng Ho Kei Matthew. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 1997-98, design report." / Chapter PART I --- INTRODUCTION --- p.P.5 / Chapter - --- personal design objective --- p.P.6 / Chapter - --- the subject --- p.P.7 / Chapter - --- the clients & users --- p.P.8 / Chapter - --- the site & context --- p.P.8 / Chapter PART II --- PROJECT ANALYSIS --- p.P.10 / Chapter - --- subject analysis --- p.P.11 / Chapter - --- client / user. analysis --- p.P.18 / Chapter - --- site / context analysis --- p.P.25 / Chapter PART III --- PROJECT FORMATION --- p.P.32 / Chapter - --- mission --- p.P.33 / Chapter - --- design strategy --- p.P.34 / Chapter - --- design development --- p.P.36 / Chapter PART IV --- FINAL PROJECT --- p.P.45 / Chapter - --- final design --- p.P.46 / Chapter - --- conclusion --- p.P.58 / Chapter PART V --- FINAL PRESENTATION --- p.P.59 / Chapter - --- final presentation panels --- p.P.60 / APPENDIX --- p.P.61 / Chapter '-i. --- "/project planning, finance & fee estimations (12-1997)" --- p.P.62 / Chapter -ii. --- /programming report (12-1997) --- p.P.63

Chu Pak Lin, Parry. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2006-2007, design report." / Chapter 1.0 --- Thesis Statement / Chapter 2.0 --- Background Information / Chapter 3.0 --- Architectural Issues of MTR Station & Underground Space / Chapter 4.0 --- Research & Approaches / Chapter 5.0 --- Site Studies / Chapter 6.0 --- The Design

Wireless Underground Sensor Networks (WUSNs) are the networks of wireless sensors that operate below the ground surface. These sensors are either buried completely in soil medium, or placed within a bounded open underground space, such as underground mines and tunnels. WUSNs enable a wide variety of novel applications, including intelligent irrigation, underground structure monitoring, and border patrol and intruder detection. This thesis is concerned with establishing reliable and efficient communications in the network of wireless sensor nodes that are deployed in either soil medium or underground mines and tunnels. In particular, to realize WUSNs in soil medium, two types of signal propagation techniques including Electromagnetic (EM) waves and Magnetic Induction (MI) are explored. For EM wave-based WUSNs, the heterogeneous network architecture and dynamic connectivity are investigated based on a comprehensive channel model in soil medium. Then a spatio-temporal correlation-based data collection schemes is developed to reduce the sensor density while keeping high monitoring accuracy. For MI-based WUSNs, the MI channel is first analytically characterized. Then based on the MI channel model, the MI waveguide technique is developed in order to enlarge the underground transmission range. Finally, the optimal deployment algorithms for MI waveguides in WUSNs are analyzed to construct the WUSNs with high reliability and low costs. To realize WUSNs in underground mines and tunnels, a mode-based analytical channel model is first proposed to accurately characterize the signal propagation in both empty and obstructed mines and tunnels. Then the Multiple-Input and Multiple-Output (MIMO) system and cooperative communication system are optimized to establish reliable and efficient communications in underground mines and tunnels.

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning

Thesis (M. Sc. (Urb. Plan.))--University of Hong Kong, 1994. / Includes bibliographical references.

Thesis (M. Sc.)--University of Hong Kong, 1992.

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning