Thesis (Ph.D. in mechanical engineering)--Washington State University, August 2005. / Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Clark R. Wilson. Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references (leaves 126-130).

Thesis (Ph.D.) - University of St Andrews, June 2009.

Thesis (M.S.)--Montana State University--Bozeman, 2006. / Typescript. Chairperson, Graduate Committee: Barry H. Pyle. Includes bibliographical references (leaves 68-72).

The British Tertiary Volcanic Province comprises central volcanic complexes with positive gravity and magnetic anomalies, some centres associated with both large volumes of continental flood basalts and regional dyke swarms. The Lundy Island is the southern most expression of Tertiary volcanism and consists of granite intruded by around 200 dykes and associated with positive gravity and magnetic anomalies. The Lundy Dyke Swarm comprises basalt/dolerite and trachyte to rhyolite intrusions within host Tertiary granite (58.7 ± 1.6 Ma) and Devonian sediments. Outcrops of dykes are confined to coastal exposures on Lundy as they are veneered by peat over most of the island. Dykes present paired magnetic anomaly profiles, which allows their trends tobe determined by proton magnetometry. The dykes have a radial disposition superimposed on a ENE-WSW regional trend. Anisotropy of magnetic susceptibility studies indicate that magma for the radial component was emplaced at shallow to moderate inclinations, suggesting a relatively shallow origin near to the western border of Lundy Island. The regional component was emplaced at shallow to sub-horizontalangles, suggesting lateral movement of magma from a possible source 12 km to the northwest. Geochemical signatures indicate that the Lundy Dyke Swarm was transitional between plume-related magmatism and partial melting of the lithospheric mantle, the magma being stored in several small storage bodies at differing depths in the upper continental crust, rather than in one large magma chamber. Basic dykes at Lee Bay (60 ± 0.6 to 63.1 ± 0.7 Ma) pre-date the Lundy Dyke Swarm and were derived from a discrete magma chamber, possibly near to Morte Point. Conversely, other dykes in North Devon (Fremington dyke - 292.4 ± 1.7 Ma; Horse-Shoe Rocks - 339.6 ± 7.4 Ma) are not directly related to Tertiary magmatism, even though the Horse-Shoe Rocks have a Tertiary palaeomagnetic overprint. The Lundy Igneous Complex (comprising granite, dykes and sub-surface basic rocks) is situated close to the intersection of the Variscan Front and the Welsh Caledonides massif where the continental thickness is between 25 and 27 km. Emplacement of magma was assisted by the heavily fractured nature of the host sediments. However, a large positive gravity anomaly to the northwest of Lundy Island does not have a corresponding magnetic anomaly and so is interpreted as the response to relatively dense uplifted basement in the Lundy Horst rather than a large volume of basic rocks. Thus, the Lundy Igneous Complex probably did not produce sub-aerial volcanic activity, as pressure in the magma chamber would not have exceeded the overlying litho static load, despite the fractured nature of the host rocks.

In this thesis we study two classes of backgrounds in Typo IIB supergravity which admit interpretation in terms of dual N = 1 Supersymmetric Field Theories. The first is obtained by wrapping D5 branes on a two-cycle inside the conifold; the second is the class containing the dual to the baryonic branch of Klebanov-Strassler. These backgrounds are related via a 'solution generating procedure' (or rotation) and have a number of interesting properties. First, we study non-Supersymmetric deformations of the baryonic branch by making use of the rotation procedure. We interpret these deformations as soft-breaking through the addition of gaugino masses, and calculate various observables which support this picture. We then explore the two-dimensional solution space of supergravity solutions associated with these deformations, finding a number of interesting limiting cases. We see that much of the structure of the Supersymmetric baryonic branch survives, even for large values of the deformation. Second, we study probe-D7 branes which wrap an internal three-dimensional manifold and lie at the equator of the transverse two-sphere, in the class of wrapped D5 brane backgrounds. We employ this method to model Chiral-symmetry breaking and present a simple diagnostic tool for determining the classical stability of such embeddings, in particular cases we find that a new type of phase transition appears, putting limits on the region of parameter space which can be used to study physics of the dual field theory. Finally, we study the relationship between confinement in a Quantum Field Theory and the presence of a first-order phase transition in its Entanglement Entropy. We determine the sufficient conditions for such a phase transition and compare to the conditions on a Rectangular Wilson Loop to probe confinement. In certain backgrounds with non-local high energy behaviour, we show that new configurations (associated with the introduction of a UV cutoff) are required in order to recover the otherwise absent phase transition. We also show that a local UV-completion, obtained using the rotation procedure, to the non-local theories has a similar effect to the cutoff.

No description available.

The Juno spacecraft has measured Jupiter's low-order, even gravitational moments, J(2)-J(8), to an unprecedented precision, providing important constraints on the density profile and core mass of the planet. Here we report on a selection of interior models based on ab initio computer simulations of hydrogen-helium mixtures. We demonstrate that a dilute core, expanded to a significant fraction of the planet's radius, is helpful in reconciling the calculated J(n) with Juno's observations. Although model predictions are strongly affected by the chosen equation of state, the prediction of an enrichment of Z in the deep, metallic envelope over that in the shallow, molecular envelope holds. We estimate Jupiter's core to contain a 7-25 Earth mass of heavy elements. We discuss the current difficulties in reconciling measured J(n) with the equations of state and with theory for formation and evolution of the planet. Plain Language Summary The Juno spacecraft has measured Jupiter's gravity to unprecedented precision. We present models of the planet's interior structure, which treat the hydrogen-helium mixture using computer simulations of the material. We demonstrate that dilute core, with the heavy elements dissolved in hydrogen and expanded outward through a portion of the planet, may be helpful for explaining Juno's measurements.

Tensile and compression strength properties of six coniferous woods were studied at the tissue level. Relationships of these properties to specific gravity variations in three adjacent growth increments of each species were explored. Pacific yew was excluded from tensile strength analyses, since the material available did not lend itself to micro-tensile testing. The main purpose of the investigation was to examine, at the tissue level, in what manner specific gravity influences tension parallel and compression perpendicular to grain strengths. Wood strength—specific gravity relationships for gross wood based on earlier studied, were compared to tissue relationships. Distributions of specific gravity and stresses within growth increments of woods having gradual transition from earlywood to latewood, as represented by western white pine, and of woods having abrupt transition, as Douglas fir, were also compared. Feasibility of radial micro-compression test methods established previously for Douglas fir were re-examined and extended to all six species. Experimental material, from freshly felled trees was never dried before physical testing, except western red cedar. Specimens for tensile and compression tests were cut from each increment studied. Micro-specific gravity determinations, based on green volume and oven-dry weight, were performed on broken tensile test specimens after extraction with standard solvents. Physical tests were carried out by established techniques. Regression analysis was employed to establish equations and curves best describing relationships of maximum micro-tensile and micro-compression stresses to specific gravity. Test results revealed highly significant relationship between maximum micro-tensile stress and specific gravity, and between maximum micro-compression stress and specific gravity. The latter relationship is curvilinear, expressed by an exponential curve fitting five of the six species studied. Pacific yew, also significantly correlated to specific gravity at 95 per cent probability, was described by the same basic equation applied to the grouping of the other five woods, but with different constants. This suggests that specific gravity influences maximum micro-compression stress variations in species of greatly different physical and anatomical, characteristics in varying degrees. Comparing tensile and compression stress—specific gravity variations of gross wood with those of wood tissue, it was found that in both properties specific gravity caused greater stress increase of gross wood than of tissue, as illustrated by respective regression lines. No definite trend of specific micro-compression stress within growth increments was found. Specific micro-tensile stress distributions showed a peak-value close to or at the initiation of latewood. Specific gravity, maximum micro-tensile stress and maximum micro-compression stress in woods having gradual transition from earlywood to latewood vary gradually across the increment, suggesting trends of a second degree parabola. In woods where transition is abrupt, the increase of these properties is abrupt at or close to the initiation of latewood. If in such woods the latewood zone is wide the distribution curve is sigmoid. Methods for testing wood tissue in radial compression, as well as theories related to the analysis of stress-deformation curves, have been verified. Ultimate load is recorded at the inflection point on the curve, beyond the proportional limit. At this phase of compression ultimate compressibility of the tracheids is achieved. / Forestry, Faculty of / Graduate