Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2010. / Committee Chair: David L. McDowell; Committee Member: G. B. Olson; Committee Member: K. A. Gall; Committee Member: Min Zhou; Committee Member: R. W. Neu. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M. Eng.)(Mechanical)--University of Pretoria, 2005. / Includes bibliographical references. Available on the Internet via the World Wide Web.

A study of the bending stresses in a pair of meshed spur gears using the finite element method is presented. The models analyzed were in the shape of a circular gear with five teeth or a five-tooth rack. A unit torque (1 lbf-ft) was applied as the form of nodal forces on the nodes around the bore hole of the driver pinion. The nodes around the bore hole of the driven gear (or the nodes along the back of the driven rack) were fixed. In order to transmit the power from the driver pinion to the driven gear (or rack), the points in contact were made coincident. Seven model groups with same diametral pitch (1.0), addendum (1.0 in.), dedendum (1.3 in.), pressure angle (20°) and hob tip radius (0.35 in.) but with varying numbers of teeth on the pinion and gear were analyzed to compute the tensile stress variation in the root fillet during the duration of contact. A model for predicting the tensile stress variation at the root fillet during the duration of contact has been created. The results were compared with AGMA and other results with agreement for the peak within 3%. / M.S.

Call number: LD2668 .T4 1984 B58 / Master of Science

Investors make investment decisions based on their risk appetite. Furthermore, when such investors consider shares as part of their investment portfolio, these investors will consider the risk profile of the company it is interested in. By taking on a certain level of risk, shareholders expect to be commensurately compensated. Shareholders of companies with relatively higher debt levels in their capital structure and therefore higher financial risk, require a relatively higher return on their investment in order to compensate for such additional risk taken. Shareholders expect return in the form of dividend pay-outs, and capital growth in the share price. A positive correlation is therefore expected between the debt levels of a company and the total return to their shareholders, i.e. the sum of the dividend pay-outs and the capital growth in the share price, also referred to as total shareholder return (TSR). The focus of this study is on the platinum industry in South Africa, as this industry is vital to the South African economy in terms of job creation and earner of foreign exchange as South Africa dominates the world production of platinum. The purpose of this study is to investigate whether there is a correlation between the debt levels and the total shareholder return (TSR) of platinum companies listed on the JSE Ltd. Quantitative research techniques were used to address the research problem, making use of secondary data and rank correlation-based research. Firstly, the debt-to-equity ratio for each company was calculated based on book values. Secondly, the TSR of each company was calculated considering the dividends received and capital growth in share price. The correlation between the TSR and the debt-to-equity ratio was determined using Spearman’s rank correlation coefficient. The results were inconclusive, i.e. no, negative and positive relationships where the relationship is for the first 12 years not significant and for the last two years significant. Therefore the final conclusion is that this study is inconclusive to support or to reject the conceptual scope of the study in that risk is concomitant to return, i.e. returns compensate for risks, therefore higher debt levels require higher total shareholder returns (and vice versa). This study contributes to the literature on capital structure decisions from a South African platinum company perspective. The core audience will be the management of South African platinum companies considering changes in their capital structure as well as investors considering investing into a listed platinum company. / MCom (Management Accountancy), North-West University, Potchefstroom Campus, 2015

Investors make investment decisions based on their risk appetite. Furthermore, when such investors consider shares as part of their investment portfolio, these investors will consider the risk profile of the company it is interested in. By taking on a certain level of risk, shareholders expect to be commensurately compensated. Shareholders of companies with relatively higher debt levels in their capital structure and therefore higher financial risk, require a relatively higher return on their investment in order to compensate for such additional risk taken. Shareholders expect return in the form of dividend pay-outs, and capital growth in the share price. A positive correlation is therefore expected between the debt levels of a company and the total return to their shareholders, i.e. the sum of the dividend pay-outs and the capital growth in the share price, also referred to as total shareholder return (TSR). The focus of this study is on the platinum industry in South Africa, as this industry is vital to the South African economy in terms of job creation and earner of foreign exchange as South Africa dominates the world production of platinum. The purpose of this study is to investigate whether there is a correlation between the debt levels and the total shareholder return (TSR) of platinum companies listed on the JSE Ltd. Quantitative research techniques were used to address the research problem, making use of secondary data and rank correlation-based research. Firstly, the debt-to-equity ratio for each company was calculated based on book values. Secondly, the TSR of each company was calculated considering the dividends received and capital growth in share price. The correlation between the TSR and the debt-to-equity ratio was determined using Spearman’s rank correlation coefficient. The results were inconclusive, i.e. no, negative and positive relationships where the relationship is for the first 12 years not significant and for the last two years significant. Therefore the final conclusion is that this study is inconclusive to support or to reject the conceptual scope of the study in that risk is concomitant to return, i.e. returns compensate for risks, therefore higher debt levels require higher total shareholder returns (and vice versa). This study contributes to the literature on capital structure decisions from a South African platinum company perspective. The core audience will be the management of South African platinum companies considering changes in their capital structure as well as investors considering investing into a listed platinum company. / MCom (Management Accountancy), North-West University, Potchefstroom Campus, 2015

A hypoid gear optimization procedure using the method of feasible directions has been developed. The objective is to reduce the gear set weight with bending strength, contact strength and facewidth-diametral pitch ratio as constraints. The objective function weight, is calculated from the geometric approximation of the volume of the gear and pinion. The design variables selected are number of gear teeth, diametral pitch, and facewidth. The input parameters for starting the initial design phase are power to be transmitted, speed, gear ratio, type of application, mounting condition, type of loading, and the material to be used. In the initial design phase, design parameters are selected or calculated using the standard available procedures. These selected values of design parameters are passed on to the optimization routine as starting points.

Originally presented as the author's Thesis--Universität Hannover, 2008. / Includes bibliographical references.

No description available.

Thesis (M. Eng.(Mechanical Engineering))--University of Pretoria, 2004. / Includes bibliographical references.