Afhandling - Copenhagen. / Summary in English and Danish. Bibliography: p. [131]-134.

Thesis (Ph. D.)--Johns Hopkins University, 1932. / Vita. "Pigeons were selected as subjects for this investigation."--P. 26. Published also as Comparative psychology monographs, v. 9, serial no. 45, February, 1934. Bibliography: p. 45-48.

Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Hong Kong, 2004. / Also available in print.

Thesis (Ph. D.)--Johns Hopkins University, 1932. / Vita. "Pigeons were selected as subjects for this investigation."--P. 26. Published also as Comparative psychology monographs, v. 9, serial no. 45, February, 1934. Bibliography: p. 45-48.

The ability to quantify leakage flow and windage heating for labyrinth seals with honeycomb lands is critical in understanding gas turbine engine system performance and predicting its component lifes. Variety of labyrinth seal configurations (number of teeth, stepped or straight, honeycomb cell size) are in use in gas turbines, and for each configuration, there are many additional geometric factors that can impact a seal’s leakage and windage characteristics. To achieve high performance in modern gas turbine engines, the labyrinth seals operate at low clearances and high rotational speed which are generally deployed with honeycomb lands on the stator. During the transient operation of aircraft engines, the stator and rotor mechanical and thermal growths differ from one another and can often result in the rotor’s incursion into the stator honeycomb structure. The incursions create rub-grooves in the honeycomb lands that can subsequently enlarge as the engine undergoes various manoeuvres. However, the effects of different honeycomb cell size, rotation and presence of rub-groove have not been thoroughly investigated in previously published work. The objective of the present research is to numerically investigate the influence of the above three factors on seal leakage and windage heating. The present work focuses the development of a numerical methodology aimed at studying above effects. Specifically, a three-dimensional CFD model is developed utilizing commercial finite volume-based software incorporating the RNG k-ε turbulence model. Detail validation of the numerical model is performed by comparing the leakage and windage heating measurements of several rig tests. The turbulent Schmidt number is found to be an important parameter governing the leakage prediction. It depends on honeycomb cell size and clearance for honeycomb seals, and Reynolds number in the presence smooth lands. The present numerical model with the modified RNG k- turbulence model predicts seal leakage and windage heating within 3-10% with available experimental data. Using the validated numerical model, a broad parametric study is conducted by varying honeycomb cell size, radial clearance, pressure ratio and rotational speed for a four-tooth straight-through labyrinth seal with and without rub-grooves. They further indicate that presence of rub-grooves increases seal leakage and reduce windage heating, specifically at smaller clearance and for larger honeycomb cell size. Rotation significantly reduces leakage with smooth stator land and smaller honeycomb cells whereas the effect is minimal for larger (3.2mm) honeycomb cells. However, at very high rotational speed seal flow reduces in all seal configurations due to high temperature rise and Rayleigh line effects. At no rub condition and lower clearance, the larger honeycomb cells leak more flow due to high bypass flow through the honeycomb cells. This results into lower pocket swirl and higher windage. When the seal clearance increases the larger honeycomb cells offers more drag to the seal flow, therefore they leak less. At higher clearances the flow travels like a strong wall jet and isolates the pocket air from honeycomb cells. Hence, at open clearances labyrinth seals with any honeycomb cell size essentially produce the same pocket swirl and windage heating.

Exposure to abnormal motion produces a variety of behavioural effects in both human and non-human species. The general purpose of the present studies was to produce and investigate some of these effects in the laboratory rat. In the first series of experiments, rats displayed appreciable decreases in reactivity to noxious stimuli presented after exposure to brief periods of different types of motion. This motion-induced antinociception was found to persist for periods of up to 15 min. A second series of experiments examined the role of the vestibular system in this motion-induced antinociception phenomenon. Rats whose peripheral vestibular apparatus had been rendered insensitive to accelerative stimuli did not exhibit motion-induced antinociception. Subsequent experiments attempted to delineate the role of some individual components of the central vestibular system but no single component investigated was found to play a major role in the production of antinociception. Experiments in this and the preceding series of experiments also demonstrated that the antinociceptive effect could be dissociated from dizziness or acute vestibular dysfunction. In the third series of experiments, the physiological mechanisms by which vestibular stimulation produces antinociception were investigated. Experiments in this series demonstrated that motion-induced antinociception could be blocked by opiate antagonists and that the motion-induced antinociceptive effect showed cross-tolerance with chronic morphine administration. These two findings strongly implicate an endogenous opiate peptide (endorphin) system as the underlying mechanism for mot ion-induced antinociception. The brief duration of the antinociceptive effect and the fact that disruption of the pituitary-adrenal axis did not affect motion-induced antinociception suggested that the opiate peptides involved were the enkephalins rather than B-endorphin. Other behavioural effects of abnormal motion were reported in the the fourth series of experiments. The resemblance between the symptoms of motion sickness and those of opiate administration suggested that endogenous opiate peptides may mediate motion sickness. Although exposure to abnormal motion did produce a substantial conditioned taste aversion (a behavioural assay for motion sickness in the rat), attempts to attenuate the aversion with two different opiate antagonists were unsuccessful. These results suggested that abnormal motion exerts its illness-producing effects through some mechanism other than an endogenous opiate system. In the final experiment, rats that were exposed to a brief period of abnormal motion subsequently exhibited a suppression of defensive burying behaviour that was similar to that produced by anxiolytic drugs. The results of this study indicate that abnormal vestibular stimulation may have a variety of different behavioural effects in rats. However, it appears that no single mechanism can account for all of these effects. / Arts, Faculty of / Psychology, Department of / Graduate

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Religion developed out of myths. Myths developed independently in different places of the world. It seems that people have the wish to explain themselves what they perceive. Our psychological setting make us journey within ourselves to develop us. This building tries to support this process with its layout and design. / Master of Architecture

This thesis document is the record of a quest for a foundation in a 'tactical making' that is both dense and lucid enough to sustain and filter hueristic discoveries, as well as manifest itself only through a residue or deposit, appropriately receding back into its proper domain. The quest required assimilation of a making mode that uses both an illusive density of proto fragments and a lucid means to ratiocination to build working channels between conjuctive and disjunctive modes of seeing, thinking, and experience. This necessary integration of reflective distance with the vitality of making is not an overt part of a modern humanities education and consequently my architecture education pushed me beyond known domains. In forming the narrative for this thesis I discovered that the architectural structure carries the story of the journey. / Master of Architecture