A dissertation submitted for the degree of Masters of Science, School of Computational and Applied Mathematics, University of Witwatersrand, Johannesburg, 2014. / The magma equation which models the migration of melt upwards through the Earth’s mantle is considered. The magma equation depends on the permeability and viscosity of the solid mantle which are assumed to be a function of the voidage . It is shown using Lie group analysis that the magma equation admits Lie point symmetries provided the permeability and viscosity satisfy either a power law, or an exponential law for the voidage or are constant. The conservation laws for the magma equation for both power law and exponential law permeability and viscosity are derived using the multiplier method. The conserved vectors are then associated with Lie point symmetries of the magma equation. A rarefactive solitary wave solution for the magma equation is derived in the form of a quadrature for exponential law permeability and viscosity. Finally small amplitude and large amplitude approximate solutions are derived for the magma equation when the permeability and viscosity satisfy exponential laws.

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Legislation can be an effective public health tool, and understanding the factors that influence legislative outcomes is advantageous for public health practitioners who propose and advocate for legislation. The literature indicates that the issues of personal freedoms, the presence or absence of strong coalition leadership, and political conditions and ideology have significant influences on the outcomes of public health legislation. The existing literature includes information about the factors that influence outcomes for legislation at the national level, and also discusses the factors that influence initiatives (particularly tobacco-related initiatives) at the state level. Little information is available, however, regarding the factors that influence the outcomes of public health legislation initiated through the Legislature at the state level in Oregon. The objective of the current research is to understand better which factors influenced the outcomes of public health legislation in the 2001 Oregon legislative session. To answer this question, I used a cross-sectional case study design to examine four pieces of public health legislation from the 2001 Oregon legislative session. The legislation and outcomes examined included 1) Senate Bill 734 / House Bill 2814, that would have allowed counties to opt out of providing family planning services to county public health clinics (in committee upon adjournment); 2) Senate Bill 99, that would have required water suppliers serving over 10,000 people to fluoridate their water (in committee upon adjournment); 3) Senate Bill 608 / House Bill 3312, that would have required insurance to cover prescription contraceptives at the same rate as are other prescriptions (in committee upon adjournment) and 4) Senate Bill 965 / House Bill 3659, that implemented a voluntary statewide health risk screening program for all firstborn children in Oregon (passed by the Legislature). Data sources for this research included the public legislative record, four Oregon newspapers (the Oregonian (Portland), the Statesman-Journal (Salem), the Herald (Baker City) and the Mail-Tribune (Medford), and tape-recorded telephone interviews with individuals involved with at least one piece of legislation. Two major and two minor factors were found to be influential in the outcomes of the legislation included in this research. The two major findings supported the existing literature, as major factors influencing outcomes were the issue of personal freedoms (expressed as an individual or local entity's right to self-determination) and the activities of effective political coalitions. Two minor factors influencing outcomes in Oregon also emerged from the research; these were the issues of economics (primarily in the State budget) and precedent (whether or not other, similar legislation or programs already existed in Oregon). The results of this research indicate that effective coalitions are necessary to a successful legislative effort, and that such coalitions operate within a broad social and political context. Future research should consider studying the development and progression of legislative efforts and coalitions prospectively over time to enable access to additional data sources such as radio and television coverage, and to prevent errors related to less-than-perfect recall of past legislation in individuals interviewed. / Graduation date: 2004

Chapter 2 contains the continuum mechanical notions for the description of the plastic behavior of sheet metal under large deformations at room temperature. As such, it includes the kinematics of a continuum body, strain and stress definitions, and a general elasto-plastic constitutive model description. This last point is complemented by the definition of anisotropy, as well as the description of some yield criteria and hardening laws. Next, Chapter 3 defines the stress strain states required to be experimentally reproduced in order to describe the initial yield locus and its displacement in the stress axis representation during plastic deformation. A review of the available experimental equipment capable of reproducing the required stress strain states is presented in order to choose the best for further construction. After consideration, those deemed the highest performing are the Miyauchi device, able to perform simple shear tests and the bi-axial testing machine, able to perform plane strain and simple shear tests separately or simultaneously. This chapter presents the mechanical features of the Miyauchi device and the bi-axial test machine that were built at the M&S Laboratory, followed by a description of the optical strain gauge chosen that allows the computation of the strain field throughout the specimens deformation area. Chapter 4 focuses on the validation of the experimental equipment. First, the homogeneity of the stress and strain fields is verified. Then, the availability of performing the plane strain, simple shear, Bauschinger and orthogonal tests is checked. The repeatability (precision) of the tests is corroborated and the accuracy is validated by comparison with finite elements simulations. In Chapter 5, the identification methods are proposed and DC06 (0,8mm thick), DP1000 (1,6mm thick) and S320GD (0,69mm thick) steels are identified according to those methods. The initial yield surface for DC06 is identified by two methods (one using the strain measurements, the other using stress measurements) for two yield criteria, which are then compared with a texture-based yield criterion and the experimental points. The initial yield surface for the other two materials is described by the Hill 1948 yield criterion identified using strain measurements. The yield surface evolution (hardening) for DC06 and S320GD is described by the Teodosiu and Hu hardening law due to the observed mechanical behavior, i.e., the Bauschinger effect and strong influence of the pre-strain when strain-path changes take place. DP1000 exhibits a high Bauschinger effect and its flow stress is not influenced by the amount of pre-strain when reversing the load; hence, its behavior is described by a kinematic hardening law. Finally, in Chapter 6, conclusions about the present work are established and equipment improvement and further topics for research are proposed, namely, the study of texture evolution, the material axis rotation and the experimental validation of new yield criteria.

I argue that, because fundamental scientific theories are attempts to tell us something about reality, we are required to take into account the metaphysical features of those theories. I claim that a guarded realism is the proper stance to take toward fundamental scientific theories: philosophically, one must guard against accepting every posit at face value. Laws of nature are one of the posits of fundamental scientific theories and, since they are part of the nomic, I argue that they cannot be eliminated from the ontology of the world. I consider whether the nomic can be reduced to the Humean base and argue that doing so leaves us with no metaphysical explanation for the regularities we observe. I agree with Galen Strawson that the world requires a metaphysically real glue to hold it together and argue that this glue is accounted for by reifying the nomic and not reducing any of the nomic concepts to the Humean base. I argue, against Helen Beebee, that a regularity theorist about laws of nature and causation makes the world out to be a world without reasons for the regularities, which is not acceptable. I consider the Best System Analysis of laws of nature in conjunction with Humean Supervenience and show that it is not able to account for objective chance in a metaphysically acceptable way. I then turn to Armstrong’s contingent relation among universals account of laws of nature and consider Bird’s ultimate argument against it. I argue that one way to overcome the argument is to allow that some universals have nontrivial modal character, which is an acceptable solution for the nomic realist. / October 2006

Univ., Diss. u.d.T.: Bourgault, Julie: L'impact juridique des nouvelles dispositions de la loi sur les normes du travail en matiere de harcelement psychologique sur le régime légal préexistant--Laval, 2005.

Schlüsselseiten aus dem Exemplar der BSB München: 4 Diss. 253. / Signaturformel: A - C4.

Univ., Diss.--Paris, 2004.

Thèse--Université de Nancy. / "Bibliographie": p. [127]-128.

Proefschrift--Utrecht. / "Stellingen": [6] p. "Literatuur": p. [173].