This dissertation is concerned with controlling the motion of a semisubmersible structure induced by high-frequency waves. The structure consists of a rigid platform and a flexible superstructure. Motion of a structure in fluids generates forces depending on the motion itself. The added mass and damping terms stemming from this motion depend on the frequency of motion. It is well known that for a given wave height, the wave energy is distributed according to a Rayleigh distribution. Because mass and damping terms vary with the frequency of the wave motion, there is an infinite number of sets of dynamical equations, one for each frequency in the Rayleigh distribution. Practical considerations make it necessary to discretize the frequency spectrum, so that there are as many dynamical equations as frequency increments. The center frequency in each increment is computed by equipartitioning of the wave energy distribution represented by a Bretschneider spectrum. The excitation forces are estimated for each increment and the design of optimal control is carried out by the Independent Modal-Space Control (IMSC) method. The net control forces can be found by summing the forces associated with each increment. The technique is demonstrated by means of a numerical example in which the wave-induced vibration of a cylindrical platform with a flexible cantilever beam is suppressed. / Ph. D. / incomplete_metadata

A majority of underground coal mine disasters in the United States are due to explosions. Current atmospheric monitoring system (AMS) practices in the US could be enhanced to facilitate data sharing and learning of the entire work force. With the inclusion of additional atmospheric monitoring and data collecting, meaningful analysis can be realized and shared with the workforce. AMS data can be utilized to advance the understanding of underground atmospheres for the entire workforce along with adding to the knowledge base for preventative planning. An AMS interface ADAMAS is suggested to facilitate this conglomeration and sharing of the data visually, so that it can be quickly processed and applied in their daily decisions. An emerging sensor technology for underground mining, fiber optics is explored and tested in emergency, or fire and explosion situations. The fiber optic methane sensor performed well in smoke only showing a slow in response time due to soot on the filter. The ADAMAS interface was tested in a large population of underground coal miners. The population varied in age, job, classification, and experience. They all primarily found it to be easy to use and helpful to them. Concerns arose when asked how this will facilitate an improved relationship with regulatory agencies. There is trepidation when it comes to additional atmospheric information sharing, that it may not be used advance understanding of mine atmospheres. The AMS data collected is individual to each mine site but can assist in the understanding of underground atmosphere as a whole. Moving forward, regulatory bodies should use this as a stepping point to consider how this information can be used to advance the field of mine ventilation and also the health and safety of the miner. / Ph. D. / Many accidents in underground coal mines in the United States are due to explosions. Explosions occur when there is a spark created in an atmosphere that contains an explosive mixture of methane and oxygen. Current monitoring in the United States standardly follows what regulators stipulate. It is suggested and tested that we use additional atmospheric monitors, including fiber optic technology, to monitor the atmosphere, trend the data and share it with the mining workforce. Shown is current trends for atmospheric monitoring systems (AMS) and out suggestion for increased monitoring and using an interface called ADAMAS for trending and sharing data visually in graphs and locations on maps. A novel sensing technology a fiber optic methane sensor was also tested in smoke conditions for its applicability in underground mines during an emergency. Both the interface and the fiber optic sensor were successful in testing. Miners found the interface easy to use and informative. The fiber optic sensor was successful sensing methane even in smoke environments although the response time of the sensor decreased.

The occurrence of multiple fatality events in the U.S. underground coal mining industry, such as the Upper Big Branch mine explosion, illustrates the need for improved methods of major safety hazard identification and control. While many solutions to reducing the risk of mine disasters have been proposed, including stricter regulation and improved technology, a comprehensive risk management approach has yet to be fully integrated in the U.S. mining industry. Comprehensive risk management systems have been developed and implemented across a multitude of heavy industries, most notably the Australian minerals industry. This research examines the successful application of risk management in these industries, along with barriers towards U.S. implementation of risk management, which include the existence of competing safety models (e.g. behavior-based safety) and compliance regulation which consumes company resources, and limits incentive for beyond compliance safety measures. Steps towards the risk-based approach, including increased regulatory pressure and proactive initiation by high-ranking industry individuals, begin with the development of risk-based knowledge within the U.S. mining community. This research reviews the development of mine safety regulation in the U.S., and identifies regulatory constraints which have affected the diffusion of risk management. The development of a risk-based online platform which could complement the existing safety systems of U.S. underground coal operations, based on the Australian RISKGATE tool, is the central work of this research. This online platform has been developed by the research participants and industry professionals whose total underground coal mining experience exceeds 1,290 years. This joint effort has yielded a body-of-knowledge which may be used as a complementary safety control reference for U.S. mine operators who wish to employ risk management policies and practices at their own operations, or identify gaps within their own safety control systems. / Master of Science / Over the last century, the safety record of the U.S. coal mining industry has steadily improved, with annual fatal incidents reaching historically low values over the last decade. Advancements in mine safety are largely attributed to increased regulatory and enforcement efforts and the enhancement of mining technology. While fatal incidents have become more intermittent, the U.S. underground coal mining industry has yet to reach its zero harm goals through current industry standards and mining practices. Risk management, the systematic mitigation of risk through proper identification, assessment, and control, has been successfully utilized by various heavy industries (chemical, aviation, military, nuclear energy, etc.) to improve worker health and safety outcomes. However, risk management has yet to be comprehensively adopted by and applied to the U.S. coal mining industry. This research examines the potential application of risk management in U.S. underground coal mining, and describes the development of a U.S.-based risk management body-of-knowledge, RISKGATE-US COAL, designed to assist U.S. coal mining operators (e.g. frontline workers, engineers, mine managers) in the identification and mitigation of the unique hazards encountered in the underground coal mine environment. RISKGATE-US COAL is contained within an online platform (alpha.riskgate.org) devised as a reference tool for U.S. underground coal mining practitioners to identify gaps within their own safety control systems.

The migration of organic contaminants in the subsurface, due to leaking underground storage tanks, includes both discrete and dissolved phase plume movements through the porous media. Such problems always involve the multiphase flow and mass transport through three phases, namely air, oil, and water. A finite element model is developed in this thesis based on the theory of multiphase flow weakly-coupled with the theory of mass transport, in a three-dimensional setting. Galerkin's method is employed to derive the finite element formulations for multiphase flow and mass transport based on the appropriate governing differential equations. The equations for multiphase flow are based on van Genuchten's model for unsaturated flow for air and water. In this model, the saturation-pressure-conductivity relations are used to obtain the constitutive behavior. The solution procedure of the resulting time dependent nonlinear equation involves using a general 0-scheme, for time integration, and a modified Picard's method, for nonlinear iteration. The governing equation for mass transport in a three-phase system is derived based on the assumption of linear partitioning between the air, oil, water, and solid phases. The equations for flow and transport are weakly-coupled through the time lagged interphase mass transfer term. A computer program called IMFTP3D is developed. The program can solve problems related to (1) multiphase immiscible flow, (2) diffusion without flow, and (3) multiphase flow weakly-coupled with mass transport. The three-dimensional model is validated for all three options based on previous two-dimensional models and laboratory experiments present in the literature. Laboratory experiments where conducted involving gasoline movements through both a one-dimensional column and a two-dimensional flume. The computer program, IMFTP3D, was then used to investigate the usefulness of the model in predicting water outflow in for the column problem and plume movements in the flume experiment. / Master of Science

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This diploma thesis is about the media representation of Ivan Martin Jirous - a famous poet, essayist, art critic and the theorist of the czech underground. Ivan Martin Jirous, nicknamed Magor, is especially famous for the fact that he closely worked with the rock band The Plastic People of the Universe, which was at the time of normalization in opposition to communist political party, and therefore its members were persecuted and imprisoned. On the other hand after the year 1989 he became important dissident and the poet. His life changes affect into his media image, which is the subject of this diploma thesis. The main aim of this thesis is to point the life of Ivan Martin Jirous on a personal, journalistic and artistic level based on the study the professional sources and literature. But also obtain a comprehensive historical and media analysis of media texts about Ivan Martin Jirous. The thesis is divided into four main chapters. The first chapter, which follows after the introduction, has descriptive character, and focuses on the person of Ivan Martin Jirous. It offers a brief overview of his life, his family, studies and jobs. The second one describes his publications and his other cultural activities. The third chapter includes a chronological list of media texts about Ivan Martin Jirous...

Tam Kwan Ping Keith. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 1998-99, design report." / Includes bibliographical references. / Chapter 1. --- Definition / Chapter 2. --- Introduction / Chapter 2.1 --- Scenario [1] / Chapter 2.2 --- Scenario [2] / Chapter 2.3 --- Scenario [3] / Chapter 3. --- Vision / Chapter 4. --- History of [cave] / Chapter 4.1 --- Troglodyte - Origin of Man / Chapter 4.2 --- Cave - Origin of Architecture / Chapter 5. --- Background - Technical / Chapter 5.1 --- Rock Support Philosophy and methods / Chapter 5.2 --- Lateral Ground Support Systems / Chapter 5.3 --- Rock Excavation Techniques / Chapter 6. --- Global Context / Chapter 6.1 --- Cavern Development in Foreign Countries / Chapter 6.2 --- Cavern Development in China / Chapter 6.3 --- Traditional Advantages of Cavern / Chapter 6.4 --- Limitation of Cavern / Chapter 6.5 --- Dialogue / Chapter 6.6 --- Problems and Potential / Chapter 7. --- Local / Hong Kong Context / Chapter 7.1 --- Hong Kong Geology / Chapter 7.2 --- Feasibility of Cavern in Hong Kong from Geo-technical perspective / Chapter 7.3 --- Symbolic meaning of Mountain / Chapter 7.4 --- Hillsides Squatters / Chapter 7.5 --- Urban + Mountain = Urban Landscape? / Chapter 7.6 --- Problems and Potential / Chapter 8. --- Site / Chapter 8.1 --- Criteria for Selection / Chapter 8.2 --- General Information and Analysis / Chapter 8.3 --- Geology and Rock Properties / Chapter 9. --- Constraints / Chapter 9.1 --- Planning - OZP / Chapter 9.2 --- Statutory Control / Chapter 9.3 --- MTR Restrictions / Chapter 9.4 --- Other Constraints / Chapter 10. --- Client / Chapter 10.1 --- Client Profile & Brief / Chapter 10.2 --- Client Organization / Chapter 11. --- Hypothesis and Potential / Chapter 12. --- Mission / Chapter 13. --- Design Strategy / Chapter 14. --- Design Intentions / Chapter 15. --- Summary and Conclusion / Chapter 15.1 --- Schedule of Accommodation / Chapter 16. --- Precedent Studies / Appendix / Bibliography

Chan Cho Wa, Carlos. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2010-2011, design report." / Chapter 0 --- Abstract --- p.2 / Chapter 0.1 --- Objective / Chapter 0.2 --- Focus and Study / Chapter 1 --- Theory --- p.6 / Chapter 1.1 --- Aldo Rossi / Chapter 1.2 --- Enric Miralles / Chapter 1.3 --- Etienne Louis / Chapter 1.4 --- Arata Isozaki / Chapter 2 --- HK Situation --- p.8 / Chapter 2.1 --- Supply and Demands in HK / Chapter 2.2 --- Architectural Treatment / Chapter 2.3 --- Locations / Chapter 2.4 --- "Government, Policy" / Chapter 2.5 --- Social Concern / Chapter 2.6 --- Religious / Chapter 2.7 --- Summary / Chapter 3 --- Typology Study --- p.14 / Chapter 3.1 --- Traditional Hill / Chapter 3.2 --- Flat Land / Chapter 3.3 --- Slab Block / Chapter 3.4 --- High Rise / Chapter 4 --- Detailed Case Studies --- p.16 / Chapter 4.1 --- Igualada Cemetery / Chapter 4.2 --- "Diamond Hill ^sff ""<;." / Chapter "4,3" --- Others / Chapter 4.4 --- First Summary / Chapter 5 --- Rock Study --- p.24 / Chapter 5.1 --- "Countryside, Town, Urban Edge" / Chapter 5.2 --- Type of Rock / Chapter 5.3 --- Method of Excavation & Tunnel / Chapter 6 --- Site Investigation --- p.26 / Chapter 6.1 --- Why the site / Chapter 6.1.1 --- Urban Edge / Chapter 6.1.2 --- Natural elements / Chapter 6.1.3 --- Traditional and New Type / Chapter 6.1.4 --- "Site nature, old cemetery and countryside" / Chapter 6.2 --- History of sites / Chapter 6.2.1 --- History of Lee Yue Mun / Chapter 6.2.2 --- History of Devil Hill / Chapter 6.3 --- Important elements in sites / Chapter 6.4 --- Zoning and Site Response / Chapter 7 --- Design Strategies --- p.32 / Chapter 7.1 --- Caved Landscape / Chapter 7.2 --- Double Layering System / Chapter 7.3 --- Mix program / Chapter 7.4 --- Linkage and Revitalizing the size / Chapter 7.5 --- Narrative Route and Program / Chapter 7.6 --- Circulation of Darkness and Light / Chapter 8 --- Design Research --- p.40 / Chapter 8.1 --- Atmospheric Drawings / Chapter 8.2 --- System Studies / Chapter 8.3 --- 8.3 Parti Models / Chapter 9 --- Design Process --- p.46 / Chapter 10 --- Lighting Study --- p.52 / Chapter 10.1 --- Single Source / Chapter 10.2 --- Combination / Chapter 10.3 --- Sequence Study / Chapter 10.4 --- Unit Study / Chapter 10.5 --- Unit of sunken niche / Chapter 10.6 --- Sequence in niche / Chapter 10.7 --- Overall Sequence / Chapter 10.8 --- Sequence of Darkness / Chapter 11 --- Final Design --- p.58 / Chapter 11.1 --- Design Summary / Chapter 11.2 --- Key Drawings / Chapter 11.3 --- Sequence / Chapter 11.4 --- Models

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