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This thesis presents a probability model to predict the maximum rotation of rocking bodies exposed to seismic excitations given specific earthquake intensity measures. After obtaining the nonlinear equations of motion and clarification of the boundaries applied to a rocking body to avoid sliding, a complete discussion is provided on the estimation of approximate period and equivalent damping ratio for the rocking motion. Thereafter, instead of using an iterative solution, which was previously proven defective, a new approximate technique is developed by finding the best representative ground motion intensities. Suitable transformation and normalization are applied to these intensities, and the Bayesian Updating approach is employed to construct a probability model. The proposed probability model is capable of accurately predicting the maximum rotation of a symmetric rocking block given displacement design spectra, peak ground acceleration, peak ground velocity, and arias intensity of an earthquake. This probabilistic model along with the approximate capacity of rocking blocks are used to estimate the fragility curves for rocking blocks with specific geometrical parameters. At the end, a comprehensive and practical form of fragility curves and numerical examples are provided for design purposes.

In turbomachinery, extra excitation forces may result from non-idealised operation conditions and may sometime cause excessive vibrations and unsteady rotor motions. The goal of this thesis is to investigate the effects of such excitation forces. The extra excitation forces investigated here are the Thomas/Alford force due to the blade tip clearance change, the steam excitation force caused by the variation of inlet steam speed and state blade trailing wake and the dominant magnetic pull force due to dynamic eccentricity of the rotor. The main research results in this thesis include: (1) The modelling of the Jeffcott rotor and the 600MW steam-turbine generator. The used in-house ??transient?? program can only handle the circular short bearings with the modified short bearing method while the simulated steam-turbine should be supported by tilting pad bearings. The first critical speeds of systems supported by tilting pad bearings are more approaching to the lab data for all four rotor models while that of journal bearing supported systems are normally lower than the real operating critical speed. (2) Applying three sorts of excitation forces into the single-stage rotor-bearing system. The numerical simulation shows that for the model with each single excitation force, all of these three forces need to reach some limit to force the system into the unsteady state. For all the three forces, higher limits are needed if the machine runs at lower running speeds. Furthermore, unbalance loading also can influence the system behaviours. As the unbalance increases, the system will still stay steady while the spectra become noisier, though the amplitude still low comparing to harmonics. (3) Combing three types of excitation forces into the assembled rotor-bearing system. The numerical simulation shows that the assembled system presents similar vibration responses as the single stage rotor-bearing system. Furthermore, these three forces cannot cancel each other and the combination will unstabilise the system. Meanwhile, the influence of the dominant magnetic pull force is less than other two forces.

The enteric nervous system (ENS) runs within the intestinal wall and is responsible for initiating and enacting several reflexes and motor patterns, including peristalsis and the complex interdigestive motor programs, known as migrating motor complexes (MMCs). The ENS consists of several neuron types including intrinsic sensory neurons, interneurons and motor neurons. A great deal is known about the anatomy, pharmacology and electrophysiology of the ENS, yet there is almost no understanding of how enteric neural circuits perform the functions that they do and how they switch from one function to another. The ENS contains intrinsic sensory neurons (ISNs) that connect to every neuron type in the ENS, including making recurrent connections amongst themselves. Thus, they are likely to play a key role, not just in sensory transduction, but in coordination of reflexes and motor patterns. This thesis has explored how these functions are performed by developing and analysing mathematical and computer models of the network of ISNs. (For complete abstract open document)

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (leaves 83-94). Also available via World Wide Web.

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (leaves 241-264). Also available via World Wide Web.

Thesis (Ph.D.) -- McMaster University, 1999. / Includes bibliographical references (leaves 154-160). Also available via World Wide Web.

Thesis (Ph.D.)--McMaster University (Canada), 1992. / Source: Dissertation Abstracts International, Volume: 54-08, Section: B, page: 4153. Adviser: Adam P. Hitchcock.

Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available in print.

Thesis--Rijksuniversiteit te Leiden. / Summary also in Dutch. Includes bibliographies. Also issued in print.