Thesis (M. Sc.)--University of Hong Kong, 1978.

No description available.

Thesis (Ph.D.)(Civil and Biosystems Engineering)--University of Pretoria, 2005. / Includes bibliographical references. Includes bibliographical references. Available on the Internet via the World Wide Web.

M.Ing. (Engineering Management) / Please refer to full text to view abstract

This dissertation analyzed data and the competitiveness model of the Taiwanese earthmoving equipment industry. Competitiveness in this industry is the most important factor impacting the struggle of businesses for existence. Thus, understanding factors affecting competitiveness is important for business decision-makers. / Thesis (PhD)--University of South Australia, 2008.

Thesis (PhD)--University of Stellenbosch, 2004. / Bibliography. Also available via the Internet.

published_or_final_version / Industrial Engineering / Master / Master of Science in Engineering

M.Phil. / The aim of this research is to study the underhood airflow thermal behaviour of the extra low profile (XLP) dozer due to the excessive heat dissipated and observed during testing sessions executed at ground level, using computational fluid dynamics (CFD). The motivation of this project is to identify the reasons of poor cooling performance of this equipment, to develop and to demonstrate the capabilities of CFD in thermal research by validating the CFD result with experiments using a scaled model, prior to analyzing the full-scale dozer ...

Thesis (PhD (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2004. / Granular flow occurs in a broad spectrum of industrial applications that range from separation and mixing in the pharmaceutical industry, to grinding and crushing, blasting, stockpile construction, flow in and from hoppers, silos, bins, and conveyer belts, agriculture, mining and earthmoving. Two totally different approaches of modelling granular flow are the Discrete Element Method (DEM) and continuum methods such as Finite Element Methods (FEM). Continuum methods can be divided into nonpolar or classic continuum methods and polar continuum methods. Large displacements are usually present during granular flow which, without remeshing, cannot be solved with standard finite element methods due to severe mesh distortion. The Particle-in-Cell (PIC) method, which is a so-called meshless method, eliminates this problem since all the state variables are traced by material points moving through a fixed mesh. The main goal of this research was to model the flow of noncohesive granular material in front of flat bulldozer blades and into excavator buckets using a continuum method. A PIC code was developed to model these processes under plane strain conditions. A contact model was used to model Coulomb friction between the material and the bucket/blade. Analytical solutions, published numerical and experimental results were used to validate the contact model and to demonstrate the code’s ability to model large displacements and deformations. The ability of both DEM and PIC to predict the forces acting on the blade and bucket and the material flow patterns were demonstrated. Shear bands that develop during the flow of material were investigated. As part of the PIC analyses, a comparison between classic continuum and polar continuum (Cosserat) results were made. This includes mesh size and orientation dependency, flow patterns and the forces acting on the blade and the bucket. It is concluded that the interaction of buckets and blades with granular materials can successfully be modelled with PIC. In the cases conducted here, the nonpolar continuum was more accurate than the polar continuum, but the polar continuum results were less dependent on the mesh size. The next step would be to apply this technology to solve industrial problems.

Thesis (MBA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Richards Bay Minerals (RBM) went through a restructuring process in 2002. The effect that these changes had on the life expectancy of the heavy earthmoving equipment (HEME) at the company’s sand dune mining operation situated at Richard’s Bay on the north coast of KwaZulu-Natal, was unknown. This study explores these, and various other factors, that influence the life expectancy of the HEME in this highly corrosive environment. During the last number of years there has been no equipment replacement philosophy at RBM and this has resulted in the average age of HEME at the mine being extremely high. This study suggests that when restructuring is implemented in the wrong way, the process can have significant negative implications. The study determines how the behaviour of especially drivers and maintenance personnel (maintainers) impacts on the expected life of the HEME at RBM. The hidden cost element of driver and maintainer unhappiness, however, is not included as part of this study. In the first part of this study project, the writer focuses on what may have caused the unhappiness, and makes suggestions for further studies aimed at addressing this unhappiness and changing the behaviour of drivers and maintainers. These suggestions should be seen as guidelines, as measures that work in one company may not necessarily work in another. The second part of the study project deals with the replacement philosophy regarding HEME at RBM. The mine has various types of equipment, but the main focus of this research falls on the following: Caterpillar 966- 980 (payloaders), track type equipment Caterpillar D7R/H (dozers), Caterpillar 988- 992 (heavy duty payloaders) and Bell B25 articulated dumptrucks (dumptrucks) Four different replacement models are investigated and discussed in detail. The model that was best aligned with the Caterpillar proposed best replacement practice, as stipulated by the Caterpillar replacement expert, is identified. Finally, a replacement cycle for the different types of equipment is proposed. / AFRIKAANSE OPSOMMING: Richardsbaai Minerale (RBM) het in 2002 deur ‘n herstruktureringsprogram gegaan. Die uitwerking wat die gevolge daarvan op die swaar grondverskuiwingsvoertuie (SGV) gehad het was onbekend. Gedurende die laaste aantal jare was daar geen vervangingsbeleid by RBM nie, en dit het meegebring dat die gemiddelde ouderdom van die SGV op die myn buitengewoon hoog is. Dit is belangrik om te bepaal wat die invloed van menslike gedrag van veral die drywers en herstelpersoneel op die verwagte leeftyd van SGV is. Die versteekte koste wat verbind word met ongelukkige drywers en herstelpersoneel maak nie deel uit van hierdie studie nie. As herstrukturering op die verkeerde manier toegepas word kan dit ‘n negatiewe impak hê. In die studie sal daar aandag gegee word aan wat die negatiewe elemente is en wat is die moontlike oorsaak daarvan. Daar word ook sekere voorstelle gemaak vir toekomstige studies om die ongelukkigheid aan te spreek en ‘n gedragsverandering na vore te bring. Die voorstelle is slegs riglyne en, wat in een maatskappy werk sal nie noodwendig in ‘n ander een werk nie. Die tweede deel van die werkstuk fokus op vervangingsteorieë met betrekking tot die SGV op RBM. Die myn het verskeie tipes SGVs maar die fokus het geval op vier soorte SGV. Hulle is Caterpillar 966- Caterpillar 980 (gemiddelde laaiers), spoor tipe toerusting Caterpillar D7R/H (stootskrapers), Caterpillar 988- Caterpillar 992 (swaargewig mobiele laaiers) en Bell B25 geartikuleerde stortings trokke (stortings trokke). Vier verskillende modelle is ondersoek en deeglik bespreek. Die model met die beste uitslae wat die mas opgekom het ten opsigte van die Caterpillar se voorgestelde beste vervangings praktyk, soos aangedui deur die Caterpillar voertuig vervangings kenner, is ge-identifiseer. Laastens word die vervangingsiklus vir die verskillende tipes toerusting voorgestel.