The modelling of multi-phase water flow is an important modern-day design tool used by engineers to develop practical systems which are beneficial to society . Multi-phase water flow can be found in many important industrial applications such as large scale conventional and nuclear power systems, heat transfer machinery, chemical process plants, and other important examples. Because of many inherent complexities in physical two-phase flow processes, no generalised system of equations has been formulated that can accurately describe the two-phase flow of water at all flow conditions and system geometries. This has led to the development of many different models for the simulation of two-phase flow at specific conditions. These models vary greatly in complexity. The simplest model that can be used to simulate two-phase flow is termed the homogeneous equilibrium (HEM) two-phase flow model. This model has been found useful in investigations of choking and flashing flows, and as an initial investigative model used before the formulation of more complex models for specific applications. This flow model is fully de ned by three conservation equations, one each for mass, momentum and energy. To close the model, an equation of state (EOS) is required to deliver system pressure values. When solving the HEM, a general practice is to employ an equation of state that is derived from a fundamental expression of the second law of thermodynamics. This methodology has been proven to deliver accurate results for two-phase system simulations. This study focused on an alternative formulation of the equation of state which was previously developed for the time dependent modelling of HEM two-phase flow systems, termed the rate form of the equation of state (RFES). The goal of the study was not to develop a new formulation of the EOS, but rather to implement the RFES in a transient simulation model and to verify that this implementation delivers appropriate results when compared to the conventional implementation methodology. This was done by formulating a transient pipe and reservoir network model with the HEM, and closing the model using both the RFES and a benchmark EOS known to deliver accurate system property values. The results of the transient model simulations were then compared to determine whether the RFES delivered the expected results. It was found that the RFES delivered sufficiently accurate results for a variety of system transients, pressure conditions and numerical integration factors. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2014

Physics education research found that graphs in kinematics have been a problem to students, even at university level. The study hence investigates what deficiencies first-year Physics students at the Central University of Technology, Bloemfontein, South Africa have in terms of transferring mathematics knowledge and understanding when solving kinematics problems. According to the National Department of Education (DoE, 2003), mathematics enables learners to have creative and logical reasoning about problems in the physical and social worlds. Graphs in kinematics are one of the domains that need that skill in mathematics. DoE (2011) further emphasises that learners should be able to collect, analyze, organize and critically evaluate information at the end of their FET sector and that include graphing in kinematics. The study started by exploring graph sense and comprehension from literature. The study further explored from a literature review students‘ problems and possible solutions in transferring their mathematics understanding and knowledge to solve physics problems. The literature study served as conceptual framework for the empirical study, i.e. the design and interpretation of questionnaires, and interview questions. The mathematics and kinematics questions of the questionnaire were divided into four constructs, namely area, gradient, reading coordinates and form/expression of graphs. The participants undertook the questionnaire and interviews voluntarily according to the research ethics. Hundred and fifty two (152) out of 234 students registered for first-year physics from the faculties of humanities (natural science), health and environmental science and engineering and information technology undertook the questionnaire. The researcher interviewed 14 students of these participants as a follow up to the responses of the questionnaire. The responses of the participants were analysed statistically to conclude this study. The average percentages of the questionnaire showed that the majority (62.7% participants) have the mathematics knowledge compared to the low percentage of 34.7 % on physics knowledge. With regard to the constructs the participants generally performed similarly on gradient, reading coordinates and form/expression, i.e. they could either answer both the corresponding mathematics and physics questions and neither of them. In the area construct, most participants with the mathematics knowledge did not transfer it to the physics context. The study further revealed that the majority of interviewees do not have an understanding of the basic physics concepts such as average velocity and acceleration. The researcher therefore recommends that physical science teachers in the FET schools should also undergo constant training in data handling and graphs by subject specialists and academic professionals from Higher Education Institutions. Other remedial actions are also proposed in the dissertation. / MSc (Natural Science Education), North-West University, Potchefstroom Campus, 2015

Dosage forms have been developed over the years for various applications. The dosage form consists of the active drug in combination with pharmaceutical excipients. The pharmaceutical excipients solubilise, suspend, thicken, dilute, emulsify, stabilise, preserve, colour and flavour medicinal agents into efficacious and appealing dosage forms. The dosage form under investigation in this study is of the oral type. The Pheroid® is a unique drug delivery system which consists of an oil-in-water emulsion system. Emulsion based drug systems provide a suitable medium for the delivery of both hydrophobic and hydrophilic drugs which can be incorporated into its oil or water phase for delivery to the site of action. These advantages make them more efficient as dosage form. Emulgels are either emulsion of oil-in-water or water-in-oil type, which is gelled by mixing with gelling agents. Incorporation of emulsion into gel increases its stability and makes it a dual control release system. The presence of the gel phase makes it a non-greasy formulation which favours good patient compliance. A strategy followed to improve the stability of the emulgel system is the packaging of the formula into single dose sachets to protect the product against physical and chemical breakdown during patient usage. All factors such as selection of gelling agent, preservatives and formulation methods influencing the stability and efficacy of Pheroid® emulgel are discussed. In this study, three different emulsifiers were added to the formula and the analysis of visual appearance, pH measurements, rheological studies, light microscopy and confocol laser scanning microscopy (CLSM) will provide an insight to the potential usage of emulgel as drug delivery system. A range of para-hydroxybenzoate esters was tested in the Pheroid® emulgel and the most suitable candidate chosen for further accelerated stability testing. It was thus possible to prepare a single dose emulgel with Carbopol® 934P (0.2% w/v) as an emulsifier, with Nipastat® (0.175% w/v) and PG (10% v/v) as preservatives into a stable dosage form suitable for further product development. / PhD (Pharmaceutics), North-West University, Potchefstroom Campus, 2014

The modelling of multi-phase water flow is an important modern-day design tool used by engineers to develop practical systems which are beneficial to society . Multi-phase water flow can be found in many important industrial applications such as large scale conventional and nuclear power systems, heat transfer machinery, chemical process plants, and other important examples. Because of many inherent complexities in physical two-phase flow processes, no generalised system of equations has been formulated that can accurately describe the two-phase flow of water at all flow conditions and system geometries. This has led to the development of many different models for the simulation of two-phase flow at specific conditions. These models vary greatly in complexity. The simplest model that can be used to simulate two-phase flow is termed the homogeneous equilibrium (HEM) two-phase flow model. This model has been found useful in investigations of choking and flashing flows, and as an initial investigative model used before the formulation of more complex models for specific applications. This flow model is fully de ned by three conservation equations, one each for mass, momentum and energy. To close the model, an equation of state (EOS) is required to deliver system pressure values. When solving the HEM, a general practice is to employ an equation of state that is derived from a fundamental expression of the second law of thermodynamics. This methodology has been proven to deliver accurate results for two-phase system simulations. This study focused on an alternative formulation of the equation of state which was previously developed for the time dependent modelling of HEM two-phase flow systems, termed the rate form of the equation of state (RFES). The goal of the study was not to develop a new formulation of the EOS, but rather to implement the RFES in a transient simulation model and to verify that this implementation delivers appropriate results when compared to the conventional implementation methodology. This was done by formulating a transient pipe and reservoir network model with the HEM, and closing the model using both the RFES and a benchmark EOS known to deliver accurate system property values. The results of the transient model simulations were then compared to determine whether the RFES delivered the expected results. It was found that the RFES delivered sufficiently accurate results for a variety of system transients, pressure conditions and numerical integration factors. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2014

Physics education research found that graphs in kinematics have been a problem to students, even at university level. The study hence investigates what deficiencies first-year Physics students at the Central University of Technology, Bloemfontein, South Africa have in terms of transferring mathematics knowledge and understanding when solving kinematics problems. According to the National Department of Education (DoE, 2003), mathematics enables learners to have creative and logical reasoning about problems in the physical and social worlds. Graphs in kinematics are one of the domains that need that skill in mathematics. DoE (2011) further emphasises that learners should be able to collect, analyze, organize and critically evaluate information at the end of their FET sector and that include graphing in kinematics. The study started by exploring graph sense and comprehension from literature. The study further explored from a literature review students‘ problems and possible solutions in transferring their mathematics understanding and knowledge to solve physics problems. The literature study served as conceptual framework for the empirical study, i.e. the design and interpretation of questionnaires, and interview questions. The mathematics and kinematics questions of the questionnaire were divided into four constructs, namely area, gradient, reading coordinates and form/expression of graphs. The participants undertook the questionnaire and interviews voluntarily according to the research ethics. Hundred and fifty two (152) out of 234 students registered for first-year physics from the faculties of humanities (natural science), health and environmental science and engineering and information technology undertook the questionnaire. The researcher interviewed 14 students of these participants as a follow up to the responses of the questionnaire. The responses of the participants were analysed statistically to conclude this study. The average percentages of the questionnaire showed that the majority (62.7% participants) have the mathematics knowledge compared to the low percentage of 34.7 % on physics knowledge. With regard to the constructs the participants generally performed similarly on gradient, reading coordinates and form/expression, i.e. they could either answer both the corresponding mathematics and physics questions and neither of them. In the area construct, most participants with the mathematics knowledge did not transfer it to the physics context. The study further revealed that the majority of interviewees do not have an understanding of the basic physics concepts such as average velocity and acceleration. The researcher therefore recommends that physical science teachers in the FET schools should also undergo constant training in data handling and graphs by subject specialists and academic professionals from Higher Education Institutions. Other remedial actions are also proposed in the dissertation. / MSc (Natural Science Education), North-West University, Potchefstroom Campus, 2015

Master of Regional and Community Planning / Department of Landscape Architecture/Regional and Community Planning / John W. Keller / Form-based codes are gaining in popularity and provide a much needed and adequate alternative to more commonly used zoning regulations. Analysis shows the inadequacies and negative consequences that zoning regulations have created over the past 100 years of use within the United States. The focus being that traditional zoning regulations create undesired and unsustainable communities. A progression of form-based codes from their origins to the use of form-based codes today shows how they can be used to influence and shape the built environment. Further examination of the evolution of form-based codes reveals the guiding principles and elements of more modern codes. When compared to traditional zoning regulations, form-based codes can assist in designing a better quality built environment by creating more conscious, significant and sustainable places and spaces within our communities. By looking at current ways in which form-based codes are implemented we can begin to define best management practices and speculate on the future of form-based codes.

Von Kooperationen zwischen Unternehmen erhoffen sich Wirtschaftspolitiker, dass sie als neue Organisationsform die Vorteile von Markt und Hierarchie in sich vereinen und kleine und mittlere Unternehmen durch zeitweilige Zusammenschlüsse größere Wettbewerbsfähigkeit gewinnen. Sie subventionieren Unternehmensverbünde (z. B. Innoregio, 1999 und Kompetenznetzwerke.de, 2000 durch das BMBF, Verbundprojekte auf den Gebieten FuE und Mikroelektronik durch das Land Sachsen) und vergeben zu ihrer Unterstützung Fördermittel für Forschungsprogramme (hier: @virtu im Rahmen der Ausschreibung zur „Arbeitsgestaltung in virtuellen Unternehmen“ durch das BMBF, 2001), aber die ökonomische Bedeutung dieser Organisationsformen ist bisher gering. Umfassende quantitative Befragungen des Zentralverbandes des Deutschen Handwerks (2002) und des Bundesverbandes Deutscher Unternehmensberater (2004) ergaben, dass Kooperationen sich häufig als sehr aufwändig erweisen und leicht zerbrechen bzw. nicht wiederholt werden. Es gilt herauszufinden, warum trotz des großen Nutzens, der durch Zusammenarbeit entstehen kann, Kooperationen nur zögernd eingegangen werden.

In this thesis, two methods for assessing the functional form of covariates in the Cox proportional hazards model are evaluated. The methods include one graphical check based on martingale residuals and one graphical check, together with a Kolmogorov-type supremum test, based on cumulative sums of martingale residuals. The methods are evaluated in a simulation study under five different covariate misspecifications with varying sample sizes and censoring degrees. The results from both methods indicate that the type of covariate misspecification, sample size and censoring degree affect the ability to detect and identify the misspecification. The procedure based on smoothed scatterplots of martingale residuals reveals difficulties with assessing whether the behaviour of the smoothed curve in the plot is an indication of a misspecification or a phenomenon that can occur in a correctly specified model. The graphical check together with the test procedure based on cumulative sums of martingale residuals is shown to successfully detect and identify three out of five covariate misspecifications for large sample sizes. For small sample sizes, especially combined with a high censoring degree, the power of the supremum test is low for all covariate misspecifications.

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Thesis (MA)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: This study explores the nature of writing instruction which can improve the writing skills of learners as it also takes into account the learners needs. The main aim is to apply the genrebased approach to written texts in Xhosa. This framework for instruction will help learners to be ready for the work place after they have left school. They will acquire the necessary writing skills, which are needed in the work place today. The genre-based use oflanguage will enable them to use written language in different situations and they should be able to write meaningful texts, which will take the reader into consideration, as required by Curriculum 2005. The approaches to teaching communicative writing skills are discussed in relation to both the critical outcomes and the specific outcomes for the learning field Language, Literacy and Communication as specified in the Curriculum 2005 (1997). The framework presented by Grabe and Kaplan (1996) is also presented in relation to the specific outcomes that need to be achieved in the Languages, Literacy and communication-learning field. Six BONA Magazine articles on sport celebrities have been analysed according to the model of text-construction within the framework proposed by Grabe and Kaplan (1996). It is concluded that these types of analytic skills are required in an effective approach to the teaching of writing to accomplish the outcomes of Curriculum 2005. / AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die aard van skryfonderrig wat die skryfvaardigheid van leerders kan verbeter en ook die leerders se behoeftes in ag neem. Die hoofdoelstelling van die studie is om die genre-gebaseerde benadering toe te pas in die analise van geskrewe tekste in Xhosa. Hierdie raamwerk vir onderrig sal leerders help om gereed te wees vir die kommunikatiewe eise van die werkplek nadat hulle die skool verlaat het. Hulle kan, deur die genre-benadering tot skryfonderrig, die vereiste skryfvaardighede ontwikkel wat in die werkplek benodig word. Die genre-gebaseerde gebruik van skriftelike taal kan leerders in staat stelom taal aan te wend in In verskeidenheid situasies, en hulle behoort in staat te wees om betekenisvolle tekste te skryf wat die leser in berekening neem, soos vereis deur Kurrikulum 2005. Die benaderings tot die onderrig van kommunikatiewe skryfvaardigheid word bespreek met betrekking tot sowel kritieke uitkomste as spesifieke uitkomste vir die leerveld Taal, Geletterdheid en Kommunikasie, soos gespesifiseer in Kurrikulum 2005 (1997 weergawe). Die raamwerk van Grabe en Kaplan (1996) word ook behandel met betrekking tot die spesifieke uitkomste in wat bereik moet word in die leerveld Tale, Geletterdheid en Kommunikasie. Ses BONA tydskrifartikels wat handeloor sportpersoonlikhede word ontleed volgens die genre-gebaseerde benadering binne die raamwerk van Grabe en Kaplan se model vir tekskonstruksie en etnografie vir skriftelike tekste. Daar word bevind dat die onderrig van hierdie soort analitiese vaardighede nodig is vir In doeltreffende benadering tot skryfonderrig vir die bereik van die uitkomste van Kurrikulum 2005.