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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Det nödvändiga väsendet : En filosofisk analys av det kosmologiska argumentet

Wernberg, Johan January 2017 (has links)
In this paper I examine the existence of God through a focus on the cosmological argument as it ispresented here. My aim is to show that this argument provides support for the existence of God. To do this I examine that which I call the three steps of the cosmological argument: the first step being the accepting of the world as an ordered something, the second step being the ultimate question why this ordered something is there to begin with and the third step being that of God viewed as the only plausible answer. I argue that the ultimate question’s claim for an ultimate answer ought to be accepted due to the inability of individual things to explain the mere existence and order of things in general, which implies that the explanation for existence and order as such is to be searched beyond those things. Regarding the third step I argue that there has to be something rather than noting and that this something is to be viewed as something living due to the orderly nature of the world. From this I, finally, argue in favor of the explanatory value of a necessary being - i.e. God.
22

Comparative Bearing Capacity Analysis of Spread Footing Foundation on Fractured Granites

Nandi, Arpita 01 August 2011 (has links)
It is evident from several studies that ultimate bearing capacities calculated by traditional methods are conservative and subjective. For large civil structures founded on spread footings, cost-effective and safer foundation could be achieved by adopting optimum ultimate bearing capacity values that are based on an objective and pragmatic analysis. There is a pressing need to modify the existing methods for accurate estimation of the bearing capacities of rocks for spread footings. In practice, foundation bearing capacities of rock masses are often estimated using the presumptive values from Building Officials Code Administrators, National Building Code, and methods adopted by the American Association of State Highway and Transportation Officials. However, the estimated values are often not realistic, and site-specific analyses are essential. In this study, geotechnical reports and drill-log data from successful geotechnical design projects founded on a wide range of granites in eastern Tennessee were consulted. Different published methods were used to calculate ultimate bearing capacity of rock mass. These methods included Peck, Hansen and Thornburn, Hoek and Brown, Army Corps of Engineers, Naval Facilities Engineering Command, and Terzaghi's general bearing capacity equations. Wide variation was observed in the calculated ultimate bearing capacity values, which ranged over about two orders of magnitude. Only two of the methods provided realistic results when validated with plate-load test data from similar rocks.
23

Bertrand Russell's Bundle Theory of Particulars

Koç, Gϋlberk 12 1900 (has links)
This thesis is an examination of Bertrand Russell's realist "bundle theory of particulars". In Russell's earlier work, the need to explain the unity and individuality of objects compelled him to accept particulars as well as universals as ultimate kinds of reality. Nevertheless, in carrying out his efforts to economize his ontology, he discovered he could not reduce properties to particulars, because there are some relations that resist nominalistic explanation, but particulars could be reduced to bundles of qualities. In this thesis, I show that the realist 'bundle theory' not only reduces the kinds of ultimate reality to one, i.e., to universal qualities, but also serves all of the purposes for which bare particulars were originally required. Specifically. I examine what I take to be the major criticisms leveled against the realist 'bundle theory': the problem of individuation, the problem of necessity, and the problem of analyticity. I defend the strength and consistency of Russell's theory and argue that it can answer to the objections. / Thesis / Doctor of Philosophy (PhD)
24

Ultimate Strength of Clamped Steel-Elastomer Sandwich Panels under Combined In-plane Compression and Lateral Pressure

Zhou, Feng 21 February 2008 (has links)
An efficient interaction formula and a semi-analytical method are developed for calculating the ultimate strength of steel-elastomer sandwich panels under combined in-plane compression and lateral pressure. By using the Galerkin method and extending the semi-analytical method to clamped sandwich panels, the governing equations of sandwich panels have been solved by the Galerkin method. The material nonlinearity is treated by iteration and a three-dimensional mesh. For the load case of pure lateral pressure, the ultimate strength from the semi-analytical method is similar to that from hinge line theory and finite element analysis (FEA). However, the semi-analytical method requires about as much computation as FEA, and it is therefore not suitable for design. Finite element modeling and nonlinear analysis are performed to calculate the ultimate strength of sandwich panels under combined load. The results agree with experimental results. This verifies the accuracy of the current finite element model. The verified finite element model is used to obtain the results for a large set of sandwich panels with various dimensions and load combinations. The FEA results for pure lateral pressure load cases are used to derive a correction factor for the hinge line formula. Statistical analysis confirms that the generalized hinge line formula gives accurate values of ultimate strength of sandwich panels under pure lateral pressure. Except for the pressure-only FEA data points, the other FEA data points are corrected so as not to count the in-plane load carried by the elastomer core. Based on the corrected FEA data points, a general expression is developed for an interaction equation. The resulting equation has a bias of -0.003 and a standard deviation of 0.029. Since the radius of the interaction curve is close to 1, this standard deviation is of the order of 3%, which shows that the ultimate strength given by the equation is very close to the FEA results. The interaction equation is so simple that the ultimate strength of clamped sandwich panels under combined in-plane compression and lateral pressure can be easily calculated. / Ph. D.
25

Ultimate Strength Analysis of Stiffened Panels Using a Beam-Column Method

Chen, Yong 16 January 2003 (has links)
An efficient beam-column approach, using an improved step-by-step numerical method, is developed in the current research for studying the ultimate strength problems of stiffened panels with two load cases: 1) under longitudinal compression, and 2) under transverse compression. Chapter 2 presents an improved step-by-step numerical integration procedure based on (Chen and Liu, 1987) to calculate the ultimate strength of a beam-column under axial compression, end moments, lateral loads, and combined loads. A special procedure for three-span beam-columns is also developed with a special attention to usability for stiffened panels. A software package, ULTBEAM, is developed as an implementation of this method. The comparison of ULTBEAM with the commercial finite element package ABAQUS shows very good agreement. The improved beam-column method is first applied for the ultimate strength analysis of stiffened panel under longitudinal compression. The fine mesh elasto-plastic finite element ultimate strength analyses are carried out with 107 three-bay stiffened panels, covering a wide range of panel length, plate thickness, and stiffener sizes and proportions. The FE results show that the three-bay simply supported model is sufficiently general to apply to any panel with three or more bays. The FE results are then used to obtain a simple formula that corrects the beam-column result and gives good agreement for panel ultimate strength for all of the 107 panels. The formula is extremely simple, involving only one parameter: the product λΠorth2. Chapter 4 compares the predictions of the new beam-column formula and the orthotropic-based methods with the FE solutions for all 107 panels. It shows that the orthotropic plate theory cannot model the "crossover" panels adequately, whereas the beam-column method can predict the ultimate strength well for all of the 107 panels, including the "crossover" panels. The beam-column method is then applied for the ultimate strength analysis of stiffened panel under transverse compression, with or without pressure. The method is based on a further extension of the nonlinear beam-column theory presented in Chapter 2, and application of it to a continuous plate strip model to calculate the ultimate strength of subpanels. This method is evaluated by comparing the results with those obtained using ABAQUS, for several typical ship panels under various pressures. / Ph. D.
26

Postmortem metabolism in porcine skeletal muscle

England, Eric M. 21 July 2015 (has links)
Once an animal is harvested for meat, skeletal muscle attempts to maintain ATP at or near antemortem levels. To maintain ATP levels postmortem, stored glycogen is catabolized to produce ATP through glycolysis and possibly oxidative metabolism. Hydrolysis of the produced ATP acidifies muscle until an ultimate pH is reached. The ultimate pH of meat directly impacts the quality characteristics of color, texture, and water holding capacity. Therefore, our research intends to describe the contributions glycolysis and oxidative metabolism play in determining ultimate pH and fresh meat quality. Traditionally, glycogen content at death was thought to be responsible for dictating ultimate pH. This was especially true in oxidative muscle with limited glycogen stores. Yet, our research indicated that in the presence of excess glycogen, oxidative muscle maintains a high ultimate pH. Rather, pH inactivation of phosphofructokinase is responsible for terminating postmortem glycolysis and brackets ultimate pH between 5.9 – 5.5. Meat with a pH below this range is uncommon. However, AMPK γ3R200Q mutant pigs produce meat with an ultimate pH near 5.3. Due to lower AMP deaminase abundance in their muscle, AMP levels are elevated late postmortem. Because AMP is a potent activator of phosphofructokinase, the aberrant meat quality from AMPK γ3R200Q mutant pigs is caused by extended postmortem glycolysis. Combined, these data further our understanding of the factors that contribute to the formation of fresh meat quality. We also characterized AMPK γ3R200Q muscle by investigating antemortem skeletal muscle lactate transport. Lactate is transported in or out of tissues by proton-linked iii monocarboxylate transporters (MCTs). Previous reports indicated that acute activation of AMPK increased monocarboxylate transporter expression in skeletal muscle of other species. Yet, it was unknown the impact chronic activation of AMPK will have on MCT1, MCT2, and MCT4 expression in pigs. Compared to wild-type pigs, the longissimus lumborum of AMPK γ3R200Q pigs increased both MCT2 and MCT4 protein expression. Our data suggest glycolytic skeletal muscle from the AMPK γ3R200Q pigs has increased capacity for antemortem lactate export from muscle and possibly increased pyruvate transport into the mitochondria. / Ph. D.
27

Consequences of Simultaneous Local and Overall Buckling in Stiffened Panels

Ghosh, Biswarup 25 April 2003 (has links)
In this thesis improved expressions for elastic local plate buckling and overall panel buckling of uniaxially compressed T-stiffened panels are developed and validated with 55 ABAQUS eigenvalue buckling analyses of a wide range of typical panel geometries. These two expressions are equated to derive a new expression for the rigidity ratio (EIx/Db)CO that uniquely identifies ¡°crossover¡± panels ¨C those for which local and overall buckling stresses are the same. The new expression for (EIx/Db)CO is also validated using the 55 FE models. Earlier work by (Chen, 2003) had produced a new step-by-step beam-column method for predicting stiffener-induced compressive collapse of stiffened panels. An alternative approach is to use orthotropic plate theory. As part of the validation of the new beam-column method, ABAQUS elasto-plastic Riks ultimate strength analyses were made for 107 stiffened panels ¨C the 55 crossover panels and 52 others. The beam-column and orthotropic approaches were also used. A surprising result was that the orthotropic approach has a large error for crossover panels whereas the beam-column method does not. Some possible reasons for this are suggested. Collapse patterns for the crossover panels are studied and classified from von Mises stress distribution at collapse. The collapse mechanism and load-deflection diagrams suggest stable inelastic post collapse behavior for most panels and an abrupt drop in load carrying capacity in only nine of the 55. / Master of Science
28

Tensile and Flexure Strength of Unidirectional Fiber-Reinforced Composites: Direct Numerical Simulations and Analytic Models

Foster, Glenn C. 14 July 1998 (has links)
A Local Load Sharing (LLS) model recently developed by Curtin and co-workers for the numerical simulation of tensile stress-strain behavior in fiber-reinforced composites is used to predict the tensile strength of metal matrix composites consisting of a Titanium matrix and unidirectionally aligned SiC fibers. This model is extended to include the effects of free boundary conditions and non-constant load gradients and then used to predict the strength of a Ti-6Al-4V matrix reinforced with Sigma SiC fibers under 4-point flexure testing. The predicted tensile and flexure strengths agree very well with the values measured by Gundel and Wawner and Ramamurty et al. The composite strength of disordered spatial fiber distributions is investigated and is shown to have a distribution similar to the corresponding ordered composite, but with a mean strength that decreases (as compared to the ordered composite) with increasing Weibull modulus. A modified Batdorf-type analytic model is developed and similarly extended to the case of non-uniform loading to predict the strength of composites under tension and flexure. The flexure model is found to be inappropriate for application to the experimental materials, but the tensile model yields predictions similar to the Local Load Sharing models for the experimental materials. The ideas and predictions of the Batdorf-type model, which is essentially an approximation to the simulation model, are then compared in more detail to a simulation-based model developed by Ibnabdeljalil and Curtin to more generally assess the accuracy of the Batdorf model in predicting tensile strength and notch strength versus composite size and fiber Weibull modulus. The study shows the Batdorf model to be accurate for tensile strength at high Weibull moduli and to capture general trends well, but it is not quantitatively accurate over the full range of material parameters encountered in various fiber composite systems. / Master of Science
29

Etické aspekty ultimate frisbee / Ethical aspects of Ultimate Frisbee

Jandová, Kateřina January 2014 (has links)
Title: Ethical Aspects of Ultimate Frisbee Objectives: The purpose of this study is to introduce one of the recent team sports - ultimate frisbee - in the matter of its ethics. The work is divided into two thematic parts. The first one deals with general introduction of the fair play problemacy including also the issue of the referees/umpires. The second part presents ultimate frisbee covering its history, game rules and the idea of the Spirit of the Game. Futhermore, the study also contains comparison of the ethics of ultimate frisbee and other team sports. Keywords: Ultimate frisbee, Spirit of the Game, ethics of sport, values in sport, referee
30

Posturální stabilita u hráčů Ultimate frisbee / Postural stability of Ultimate frisbee players

Juranová, Magdalena January 2021 (has links)
Title: Postural stability in Ultimate frisbee players Aims: The aim of the work is to objectively measure and evaluate the dynamic postural stability of a deliberately selected group of Czech Utimate frisbee (UF) players and then compare the measured results with the "Athles Norm 20-30" (AN 20-30) standard, set for the sporting population. The postural stability of the research group of probands was measured once using the computer dynamic posturography - NeuroCom Smart EquiTest System. A partial goal of the work was to describe the results of measuring postural stability with respect to pivoting. This characteristic movement is used by UF players to obtain a suitable position for passing to a teammateduring the game. Methods: This is a scientific research work, specifically a quantitative observational cross-sectional study. The research group (n = 28) was, on the basis of predetermined criteria (to be an active UF player registered under the organization ČALD (Czech Flying Disc Association), age 18-35 years, to attend UF for at least 3 years and to have at least one national team start at the European Championships or in higher competition). UF players who met these criteria were included. Measurement on the Smart EquiTest System from NeuroCom was chosen as an objective way of evaluating postural...

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