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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.
11

Development of environmentally-friendly polymeric materials based on polylactide and poly[(butylene succinate)-co-adipate] blends.

Ojijo, Vincent Omondi. January 2013 (has links)
D. Tech. Polymer Technology. / Objectives of this work were to develop PLA/PBSA-based hybrid materials with better barrier properties, thermal stability, impact strength and at the same time, have relatively good strength and modulus. The specific objectives were: 1) To optimise PLA/PBSA blend composition for the desired blend properties. This entailed understanding of the role of specific interfacial area obtained from the morphologies of the blends in controlling the properties of the same and relate qualitatively, the phase morphologies to the properties of the PLA/PBSA blends. 2) To study the effect of annealing on the properties of PLA/PBSA blends. 3) To study the effect of organic modifiers on clay surfaces and the interlayer d-spacing of the clay on the morphology and properties of PLA/PBSA-clay composites 4) To study clay dispersion at various loadings and how it affects the crystallization of PLA and PBSA components in the blend.5) To study clay loading effect on the thermal and mechanical properties of the PLA/PBSA-clay composites. 6) To optimise the processing parameters, vis-a-vis: reaction time, coupling agent content, PLA/PBSA composition and processing sequence during in-situ reactive compatibilization of PLA/PBSA blends. 7) To improve the thermal stability and barrier properties through reactive processing of PLA/PBSA, in the presence of organoclays and a coupling agent. 8) To study the rheological properties of the blends prepared, as a function of clay content in the physically and reactively compatibilized PLA/PBSA blends.
12

Field, generalised theory and finite element analysis of a six-phase squirrel cage induction machine.

Appiah, Edward Kofi. January 2013 (has links)
M. Tech. Electrical Engineering. / Investigates the mathematical modelling, analysis and simulation of a six-phase squirrel cage induction machine. This dissertation is the report of the analysis and simulation of this machine through three methods, namely: The direct-quadrature axis (dqxy0102) based on generalised theory of electric machines, which enabled the machine to be mathematically modelled in the arbitrary reference frame; the classical magnetic field distribution analysis; and the finite element method (fem). The resulting models of the analysis of the six-phase squirrel cage induction machine are implemented by simulation using appropriate software. The simulations generate unique results of the steady-state and the dynamic performance characterising the performance of the six-phase squirrel cage induction machine. Tests are conducted on a 1.5 kW experimental machine whereby the performance characteristics of the theoretical analysis and simulations are validated with the experimental results. The results of the three are compared among themselves, and also with the experimental results to appraise the suitability of each method for the modelling and analysis of the hpo machine.Even though six-phase machine is considered in this study it is believed that the methods as applied in this work are generally applicable to hpo squirrel cage induction machine of any number of phases.
13

The impact of organisational structure on the deployment of enterprise architecture.

Mphahlele, Leshoto Dinao Modulathoko. January 2011 (has links)
M. Tech. Informatics Tshwane University of Technology 2011. / The demand for better services by customers, citizens keeps increasing at rapid rate. The information technology artefacts are deployed to enable and support processes and activities for improved services, and to give the organisation leverage on the competitive advantage. The deployment of the information technology artefacts to enable, facilitate and support services is done through engineering approaches and methods, such as the enterprise architecture. Many organisations have shown interest, and have deployed the enterprise architecture in the recent years. Even though the enterprise architecture has become an increasingly mature field of work, yet many organisations still struggle with the development and implementation. What and where the challenges are in the deployment of enterprise architecture continue to be a debate. This study adopted two organisations as case studies. The organisations were used to understand the deployment of enterprise architecture through a third eye, using the lens of the structuration theory and also to understand the different non-technical challenges that exists within the deployment of the enterprise architecture in organisations
14

An evaluation of AriDeM parallel architecture model using a case study

Mukala, Mulamba Patrick. January 2011 (has links)
M. Tech. Software Development Tshwane University of Technology 2011. / The von Neumann model has been for years a successful model of computation architecture in sequential computing. This model provides both consistency and synchronization in the development of computer products such as application algorithms, computer architecture as well as programming languages. The success of this model of sequential computation is due extensively to the fact that it is an efficient bridge between software and hardware: high-level languages can be efficiently compiled on to this model; yet it can be efficiently implemented in hardware. The demand for solving large and complex problems in a relative short time has motivated scientists to improve computational performance by adopting parallel computing. Unfortunately, there has not been the similar success in terms of a unifying model of computation in parallel computing. The need for such a unifying parallel model or set of models is heightened by the greater demand for performance and the greater diversity among machines. The author argues that an equivalent bridge between software and hardware is required for parallel computation since the latter is considered the future of computing. This dissertation expands a little further in motivating the need for a new model of parallel computation and considers one such model called AriDeM.
15

Effect of cooling rate on base metals recovery from copper smelting slag.

Tshiongo, Nkhumeleni. January 2011 (has links)
M. Tech. Metallurgical Engineering. / Aims to recover base metals (Cu, Co, Pb and Zn) that are trapped in the slag produced during copper matte smelting process in a water jacket furnace by leaching of the slag and to study the effect of the cooling rate on the leaching of the metals in acidic and in basic media.
16

A framework for deployment of is risk management system

Odejide, Abayomi Adeolu. January 2011 (has links)
Thesis (MTech. degree in Business Information Systems)-- Tshwane University of Technology 2011. / This research aimed to investigate and understand risks and risk management system and how risk management system was deployed in organisations. In order to achieve this, it was necessary to understand what risk is and also what risk management was. It was also necessary to understand the role information systems played in the deployment of risk management systems. The data gathered from the interview was analysed with structuration theory. Structuration theory enabled the researcher to have a clearer view of the problems in the organisations as it borders around risks. The analyses lead to some findings. Structuration theory played the role of a lens through which the problem was viewed. The findings were then used to develop a framework. It was intended that after this study the framework developed will be used for risk management in organisations. It was also intended that adoption of this framework for use in organisations will reduce the amount of resources wasted on management of risks which could have been spent on other things that are much more useful to the organisations.
17

The determination of solubility of liquids in supercritical fluids using dielectric constants

Wabula, Kazamwali Serge. January 2011 (has links)
M. Tech. Chemical Engineering. / The solubility of highly volatile non polar solutes (hexane, toluene and benzene) was determined in CO2, in the vicinity of supercritical conditions using a method employing dielectric constants. This method is based on the measurement of the dielectric constant of the saturated supercritical solution and that of the supercritical solvent as a function of pressure along different isotherms, by using the Clausius- Mossotti function. Results were in agreement with literature values, proving that this method can be used to determine the solubility of a solute in a pressurized gas. The results obtained demonstrate the capability of the dielectric constant method as a nonintrusive, simple and efficient means of determining accurately the solubility of liquids in supercritical solvents.
18

Adoption of computer aided audit techniques by information systems auditors : applying the UTAUT framework.

Paledi, Victor Ntala. January 2011 (has links)
Thesis (MTech. degree in Business Information Systems)-- Tshwane University of Technology 2011. / Information systems are defined as a group of interconnected components (people, organisation and technology) that function together to extract, regain, route, accumulate and distribute information, with the aim of business decision making and operational activities in an organisation and other business. As a result, nformation systems are being deployed by organisation to help assure that their daily activities are completed seamlessly. Thus, organisational stakeholders invest a vast amount of money in the deployment of these systems. Furthermore, volumes of organisational data stored within these systems increases on regular basis. As the volume of data and the complexity of information systems increase, business managers expect information systems auditors to become even more relevant and rigorous as these auditors have to ensure that possible risks that these nformation systems may inherent are mitigated. International Auditing standards and best practices emphasise the use of Computer Aided Audit Techniques by IS auditors, within their audit engagements. However, the level of compliance to these international auditing standards and best practices by the South African information systems auditors is still questionable. An empirical study conducted by Vasile-Daniel (2010) indicated that even if technology is accepted, few (if not all) of nformation systems auditors still deploy traditional audit methods within their audit engagements. Currently, auditors were observed to use Computer Aided Audit Techniques only to select random test samples but not necessarily to audit entirely using Computer Aided Audit Techniques. That is, they often revert to executing their audit engagements following the traditional methods. To the preceding point, the present study sought to explore factors that could be influencing the nformation systems auditors not to utilize Computer Aided Audit Techniques fully. The study, underpinned by the Unified Theory of Acceptance and Use of Technology (UTAUT), investigated the use or adoption of Computer Aided Audit Techniques by information systems auditors within a financial institution. The study revealed that senior management support, availability of resources, personal growth, increased productivity, and lack of relevant training tend to be the main factors, amongst others, influencing the use and adoption of Computer Aided Audit Techniques.
19

Ubiquitous learning support in a learning management system environment

Phahlane, Mampilo Magdeline. January 2012 (has links)
M. Tech. Business Information Systems Tshwane University of Technology 2012. / The challenge of providing ubiquitous personalized learning support, sensitive to the learner's background is still prevalent in South African higher education environments. Thus the research argument driving this dissertation is that learning resources and support sensitive to the learner's context should follow the learners, regardless of location and time. In this context, resources include knowledgeable peers who could provide on-demand academic support regardless of time and space. In the study, a learning management system was suggested as a learning environment that could leverage the challenge of providing ubiquitous learning support. The purpose of the research was to understand learning activities and how ubiquitous learning can be supported using learning management systems, in a higher education environment. Subsequently, the goal of the study was to conceptualize a framework for ubiquitous learning support through learning management systems.
20

Bismuth and antimony modified platinum catalysts for the selective oxidation of cinnamyl alcohol.

Nyamunda, Benias Chomunorwa. January 2012 (has links)
D. Tech. Chemistry.

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