A multitude of processes cooperate to produce the sensation of sound. The key initial step, the transformation from mechanical motion into an electrical signal, takes place in highly specialized mechanosensitive organelles that are called hair bundles due to their characteristic appearance. Each hair bundle comprises many apposed cylindrical stereocilia that are located in a liquid-filled compartment of the inner ear. The viscous liquid surrounding the hair bundle dissipates energy and dampens oscillations, which poses a fundamental physical challenge to the high sensitivity and sharp frequency selectivity of hearing. To understand the structure-function relationship in this complex system, a realistic physical model of the hair bundle with an appropriate representation of the fluid-structure interactions is needed to identify the relevant physical effects. In this work a novel approach is introduced to analyze the mechanics of the fluid-structure interaction problem in the inner ear. Because the motions during normal mechanotransduction are much smaller than the geometrical scales, a unified linear system of equations describes with sufficient accuracy the behavior of the liquid and solid in terms of a displacement variable. The finite-element method is employed to solve this system of partial differential equations. Based on data from the hair bundle of the bullfrog's sacculus, a detailed model is constructed that resolves simultaneously the interaction with the surrounding liquid as well as the coupling liquid in the narrow gaps between the individual stereocilia. The experimental data are from high-resolution interferometric measurements at physiologically relevant amplitudes in the range from a fraction of a nanometer to several tens of nanometers and over a broad range of frequencies from one millihertz to hundred kilohertz. Different modes of motion are analyzed and their induced viscous drag is calculated. The investigation reveals that grouping stereocilia in a bundle dramatically reduces the total drag as compared to the sum of the drags on individual stereocilia moving in isolation. The stereocilia in a hair bundle are interconnected by oblique tip links that transmit the energy in a sound to the mechanotransduction channels and by horizontal top connectors that provide elastic coupling between adjacent stereocilia. During hair-bundle deflections, the tip links induce additional drag by causing small but very dissipative relative motions between stereocilia; this effect is offset by the horizontal top connectors that restrain such relative movements, assuring that the hair bundle moves as a unit and keeping the total drag low. In the model the stiffness of the links, the stiffness of the stereocilia, and the geometry are carefully adjusted to match experimental observations. The references are stiffness and drag measurements, as well as the coherence measurements for the bundle's opposite edges, both with and without the tip links. The results are further validated by a comparison with the relative motions measured in a sinusoidally stimulated bundle for the distortion frequencies at which movements are induced by the nonlinearity imposed by channel gating. The model of the fluid-structure interactions described here provides insight into the key step in the perception of sound and the method presented provides an efficient and reliable approach to fluid-structure interaction problems at small amplitudes. / Bei der Hörwahrnehmung eines Klangs spielen viele komplexe Prozesse zusammen. Der Schlüsselprozess, die Umwandlung mechanischer Schwingungsbewegung in elektrische Signale, findet in den Haarbündeln im Innenohr statt. Diese Haarbündel sind hoch entwickelte mechanosensitive Organellen, bestehend aus vielen nahe beieinander stehenden Stereozilien umgeben von Flüssigkeit. Die beträchtliche Viskosität dieser Flüssigkeit führt zur Energiedissipation und zur Schwingungsdämpfung, was im Gegensatz zur bekannten hohen Empfindlichkeit und der ausgezeichneten Frequenzselektivität der Hörwahrnehmung steht. Um die Komponenten des Haarbündelsystems in ihrem funktionalen Zusammenspiel besser zu verstehen, bedarf es eines wirklichkeitsgetreuen Modells unter Einbeziehung der Wechselwirkung zwischen Flüssigkeit und Struktur. Mit dieser Arbeit wird ein neuer Ansatz vorgestellt, um die Mechanik der Fluid-Struktur-Wechselwirkung im Innenohr zu analysieren. Da die Bewegungen bei der normalen Mechanotransduktion wesentlich kleiner als die geometrischen Abmessungen sind, ist es möglich, das Verhalten von Fluid und Struktur in Form der Verschiebungsvariable in einem linearen einheitlichen System von Gleichungen ausreichend genau zu beschreiben. Dieses System von partiellen Differentialgleichungen wird mit der Finite-Elemente-Methode gelöst. Basierend auf experimentell ermittelten Daten vom Haarbündel des Ochsenfrosches wird ein detailliertes Modell erstellt, welches sowohl die Interaktion mit der umgebenden Flüssigkeit als auch die koppelnde Flüssigkeit in den engen Spalten zwischen den einzelnen Stereozilien erfasst. Die experimentellen Daten sind Ergebnisse von hochauflösenden interferometrischen Messungen bei physiologisch relevanten Bewegungsamplituden im Bereich von unter einem Nanometer bis zu mehreren Dutzend Nanometern, sowie über einen breiten Frequenzbereich von einem Millihertz bis hundert Kilohertz. Das Modell erlaubt die Berechnung der auftretenden viskosen Widerstände aus der numerischen Analyse der verschiedenen beobachteten Bewegungsmoden. Es kann gezeigt werden, dass durch die Gruppierung zu einem Bündel der Gesamtwiderstand drastisch reduziert ist, im Vergleich zur Summe der Widerstände einzelner Stereozilien, die sich individuell und unabhängig voneinander bewegen. Die einzelnen Stereozilien in einem Haarbündel sind durch elastische Strukturen mechanisch miteinander verbunden: Die Energie des Schalls wird durch schräg angeordnete sogenannte Tiplinks auf die mechanotransduktiven Kanäle übertragen, wohingegen horizontale Querverbindungen die Stereozilien direkt koppeln. Während der Haarbündelauslenkung verursachen die Tiplinks zusätzlichen Widerstand durch stark dissipative Relativbewegungen zwischen den Stereozilien. Die horizontalen Querverbindungen unterdrücken diese Bewegungen und sind dafür verantwortlich, dass sich das Haarbündel als Einheit bewegt und der Gesamtwiderstand gering bleibt. Die Steifigkeit der Stereozilien und der Verbindungselemente sowie deren Geometrie sind in dem Modell sorgfältig angepasst, um eine Übereinstimmung mit den Beobachtungen aus verschiedenen Experimenten zu erzielen. Als Referenz dienen Steifigkeits- und Widerstandsmessungen, sowie Kohärenzmessungen für die gegenüberliegenden Außenkanten des Bündels, die jeweils mit und ohne Tiplinks durchgeführt wurden. Darüberhinaus sind die Ergebnisse durch den Vergleich mit experimentell beobachteten Relativbewegungen validiert, die das Haarbündel infolge von sinusförmiger Anregung bei Distorsionsfrequenzen zeigt. Diese haben ihren Ursprung in dem nichtlinearen Prozess des öffnens von Ionenkanälen. Das entwickelte Modell eines Haarbündels liefert neue Einblicke in den Schlüsselprozess der auditiven Wahrnehmung. Zur Behandlung von Problemen der Fluid-Struktur-Wechselwirkungen bei kleinen Amplituden hat sich der hier ausgearbeitete Ansatz als effizient und zuverlässig erwiesen.

Le problème inverse en électroencéphalographie (EEG) est la localisation de sources de courant dans le cerveau utilisant les potentiels de surface sur le cuir chevelu générés par ces sources. Une solution inverse implique typiquement de multiples calculs de potentiels de surface sur le cuir chevelu, soit le problème direct en EEG. Pour résoudre le problème direct, des modèles sont requis à la fois pour la configuration de source sous-jacente, soit le modèle de source, et pour les tissues environnants, soit le modèle de la tête. Cette thèse traite deux approches bien distinctes pour la résolution du problème direct et inverse en EEG en utilisant la méthode des éléments de frontières (BEM): l’approche conventionnelle et l’approche réciproque. L’approche conventionnelle pour le problème direct comporte le calcul des potentiels de surface en partant de sources de courant dipolaires. D’un autre côté, l’approche réciproque détermine d’abord le champ électrique aux sites des sources dipolaires quand les électrodes de surfaces sont utilisées pour injecter et retirer un courant unitaire. Le produit scalaire de ce champ électrique avec les sources dipolaires donne ensuite les potentiels de surface. L’approche réciproque promet un nombre d’avantages par rapport à l’approche conventionnelle dont la possibilité d’augmenter la précision des potentiels de surface et de réduire les exigences informatiques pour les solutions inverses. Dans cette thèse, les équations BEM pour les approches conventionnelle et réciproque sont développées en utilisant une formulation courante, la méthode des résidus pondérés. La réalisation numérique des deux approches pour le problème direct est décrite pour un seul modèle de source dipolaire. Un modèle de tête de trois sphères concentriques pour lequel des solutions analytiques sont disponibles est utilisé. Les potentiels de surfaces sont calculés aux centroïdes ou aux sommets des éléments de discrétisation BEM utilisés. La performance des approches conventionnelle et réciproque pour le problème direct est évaluée pour des dipôles radiaux et tangentiels d’excentricité variable et deux valeurs très différentes pour la conductivité du crâne. On détermine ensuite si les avantages potentiels de l’approche réciproquesuggérés par les simulations du problème direct peuvent êtres exploités pour donner des solutions inverses plus précises. Des solutions inverses à un seul dipôle sont obtenues en utilisant la minimisation par méthode du simplexe pour à la fois l’approche conventionnelle et réciproque, chacun avec des versions aux centroïdes et aux sommets. Encore une fois, les simulations numériques sont effectuées sur un modèle à trois sphères concentriques pour des dipôles radiaux et tangentiels d’excentricité variable. La précision des solutions inverses des deux approches est comparée pour les deux conductivités différentes du crâne, et leurs sensibilités relatives aux erreurs de conductivité du crâne et au bruit sont évaluées. Tandis que l’approche conventionnelle aux sommets donne les solutions directes les plus précises pour une conductivité du crâne supposément plus réaliste, les deux approches, conventionnelle et réciproque, produisent de grandes erreurs dans les potentiels du cuir chevelu pour des dipôles très excentriques. Les approches réciproques produisent le moins de variations en précision des solutions directes pour différentes valeurs de conductivité du crâne. En termes de solutions inverses pour un seul dipôle, les approches conventionnelle et réciproque sont de précision semblable. Les erreurs de localisation sont petites, même pour des dipôles très excentriques qui produisent des grandes erreurs dans les potentiels du cuir chevelu, à cause de la nature non linéaire des solutions inverses pour un dipôle. Les deux approches se sont démontrées également robustes aux erreurs de conductivité du crâne quand du bruit est présent. Finalement, un modèle plus réaliste de la tête est obtenu en utilisant des images par resonace magnétique (IRM) à partir desquelles les surfaces du cuir chevelu, du crâne et du cerveau/liquide céphalorachidien (LCR) sont extraites. Les deux approches sont validées sur ce type de modèle en utilisant des véritables potentiels évoqués somatosensoriels enregistrés à la suite de stimulation du nerf médian chez des sujets sains. La précision des solutions inverses pour les approches conventionnelle et réciproque et leurs variantes, en les comparant à des sites anatomiques connus sur IRM, est encore une fois évaluée pour les deux conductivités différentes du crâne. Leurs avantages et inconvénients incluant leurs exigences informatiques sont également évalués. Encore une fois, les approches conventionnelle et réciproque produisent des petites erreurs de position dipolaire. En effet, les erreurs de position pour des solutions inverses à un seul dipôle sont robustes de manière inhérente au manque de précision dans les solutions directes, mais dépendent de l’activité superposée d’autres sources neurales. Contrairement aux attentes, les approches réciproques n’améliorent pas la précision des positions dipolaires comparativement aux approches conventionnelles. Cependant, des exigences informatiques réduites en temps et en espace sont les avantages principaux des approches réciproques. Ce type de localisation est potentiellement utile dans la planification d’interventions neurochirurgicales, par exemple, chez des patients souffrant d’épilepsie focale réfractaire qui ont souvent déjà fait un EEG et IRM. / The inverse problem of electroencephalography (EEG) is the localization of current sources within the brain using surface potentials on the scalp generated by these sources. An inverse solution typically involves multiple calculations of scalp surface potentials, i.e., the EEG forward problem. To solve the forward problem, models are needed for both the underlying source configuration, the source model, and the surrounding tissues, the head model. This thesis treats two distinct approaches for the resolution of the EEG forward and inverse problems using the boundary-element method (BEM): the conventional approach and the reciprocal approach. The conventional approach to the forward problem entails calculating the surface potentials starting from source current dipoles. The reciprocal approach, on the other hand, first solves for the electric field at the source dipole locations when the surface electrodes are reciprocally energized with a unit current. A scalar product of this electric field with the source dipoles then yields the surface potentials. The reciprocal approach promises a number of advantages over the conventional approach, including the possibility of increased surface potential accuracy and decreased computational requirements for inverse solutions. In this thesis, the BEM equations for the conventional and reciprocal approaches are developed using a common weighted-residual formulation. The numerical implementation of both approaches to the forward problem is described for a single-dipole source model. A three-concentric-spheres head model is used for which analytic solutions are available. Scalp potentials are calculated at either the centroids or the vertices of the BEM discretization elements used. The performance of the conventional and reciprocal approaches to the forward problem is evaluated for radial and tangential dipoles of varying eccentricities and two widely different skull conductivities. We then determine whether the potential advantages of the reciprocal approach suggested by forward problem simulations can be exploited to yield more accurate inverse solutions. Single-dipole inverse solutions are obtained using simplex minimization for both the conventional and reciprocal approaches, each with centroid and vertex options. Again, numerical simulations are performed on a three-concentric-spheres model for radial and tangential dipoles of varying eccentricities. The inverse solution accuracy of both approaches is compared for the two different skull conductivities and their relative sensitivity to skull conductivity errors and noise is assessed. While the conventional vertex approach yields the most accurate forward solutions for a presumably more realistic skull conductivity value, both conventional and reciprocal approaches exhibit large errors in scalp potentials for highly eccentric dipoles. The reciprocal approaches produce the least variation in forward solution accuracy for different skull conductivity values. In terms of single-dipole inverse solutions, conventional and reciprocal approaches demonstrate comparable accuracy. Localization errors are low even for highly eccentric dipoles that produce large errors in scalp potentials on account of the nonlinear nature of the single-dipole inverse solution. Both approaches are also found to be equally robust to skull conductivity errors in the presence of noise. Finally, a more realistic head model is obtained using magnetic resonance imaging (MRI) from which the scalp, skull, and brain/cerebrospinal fluid (CSF) surfaces are extracted. The two approaches are validated on this type of model using actual somatosensory evoked potentials (SEPs) recorded following median nerve stimulation in healthy subjects. The inverse solution accuracy of the conventional and reciprocal approaches and their variants, when compared to known anatomical landmarks on MRI, is again evaluated for the two different skull conductivities. Their respective advantages and disadvantages including computational requirements are also assessed. Once again, conventional and reciprocal approaches produce similarly small dipole position errors. Indeed, position errors for single-dipole inverse solutions are inherently robust to inaccuracies in forward solutions, but dependent on the overlapping activity of other neural sources. Against expectations, the reciprocal approaches do not improve dipole position accuracy when compared to the conventional approaches. However, significantly smaller time and storage requirements are the principal advantages of the reciprocal approaches. This type of localization is potentially useful in the planning of neurosurgical interventions, for example, in patients with refractory focal epilepsy in whom EEG and MRI are often already performed.

Lors du développement et de l'introduction d'un nouvel aliment, la compréhension des croyances, attitudes et préférences sensorielles des consommateurs est très importante. Cette thèse présente une série d'études cross-culturelles, France vs. Vietnam, sur la représentation des consommateurs vis-à-vis de produits à base soja et sur la perception et la préférence des yaourts à base de soja, un produit dérivé du soja récemment développé pour le marché français et n'existant pas sur le marché vietnamien. Malgré une image favorable du soja sur le plan nutritionnel et sur la santé, les participants français ont rapporté ne pas consommer ce type de produit, la barrière à sa consommation étant son goût de soja. Ce résultat a été confirmé par un test de consommateurs au cours duquel les participants français ont donné une très faible évaluation hédonique pour les yaourts de soja. Les consommateurs vietnamiens, consommateurs traditionnels du soja, n'ont également pas apprécié ces produits. Une série de yaourts mixtes dans lesquels le lait de vache a été partiellement remplacé par celui de soja a été fabriquée. Les tests consommateurs ont montré que pour les deux pays, le yaourt fabriqué avec une proportion de lait de soja inférieure à 50% a reçu une note moyenne supérieure à 5 sur une échelle de 1 à 9. Le rôle de la familiarité sur les préférences alimentaires ainsi que l'impact de l'exposition culturelle sur les changements des croyances et attitudes à l'âge adulte ont été confirmés. La présente étude contribue à la caractérisation des deux cultures sur leur acceptabilité d'un nouvel aliment

This study is an investigation into water management policies in South Africa, their effect on water users and the perceptions users have of these policies. The investigation begins with an exposition of concepts such as water demand management (WDM), as well as integrated water resource management (IWRM). A sub-discourse of the main theme is the societal tendency to neglect its common property. Garret Hardin's groundbreaking observations on the "tragedy of the commons" (1968) are explored in an effort to locate issues of relevance in effective water management strategies. In contemplating the commons, it is evident that aspects of morality and ethics are involved. The morality of a society be it in a global or national context, seems to manifest itself in legislation and policies, and in the way these are implemented. The relevance of good governance, hydropolitics and sustainable development is also discussed to provide the necessary theoretical background to an understanding of the relationship between consumers and the water commons. Access to safe drinking water is protected in the Constitution of the Republic of South Africa Act, 108 of 1996. Flowing from the government's obligation to take reasonable legislative and other measures to achieve the progressive realisation of fundamental human rights stipulated in section 27(2) of the Constitution, the challenge since 1994 has been to provide access to water for all inhabitants and to manage the available water resources effectively. Furthermore, the objective of subsequent water legislation such as the National Water Act, 36 of 1998 and regulatory plans, like the National Water Resource Strategy has been to incorporate international trends in water governance. The Department of Water and Environmental Affairs (DWEA) divided South Africa into 19 regions, called water management areas (WMA). In this study, attention is focused on what constitutes a catchment and how a catchment management agency (CMA) governs its water resources. A description is provided of the functions of water user associations (WUAs) and how ththe Lower Orange Catchment Management Area is, for example, the blueprint from which stakeholders develop their goals. In this study, the water situation in the Lower Orange Water Management Area is under scrutiny. The focus is on the three main institutional components of water management (the Lower Orange catchment management, the Upington Islands Water User Association [UIWUA] and the //Khara Hais Local Municipality). The progress of the establishment of the Lower Orange Catchment Management Agency is outlined over a period of five years. Meanwhile, the Upington Islands Water User Association was developed and this has grown in stature. The work being done by these institutions is investigated by looking at grassroots effects, especially in respect of irrigation activities. The unique water management circumstances of the //Khara Hais Local Municipality are then investigated along with the plans outlined in their Integrated Development Plan {lOP) and their Water Services Development Plane Internal Strategic Perspective (ISP) of(WSDP). Because local irrigation operations consume most of the available surface water in the Lower Orange Water Management Area, irrigation farmers and their activities warrant closer attention. A historical overview is given of the development of irrigation in the region followed by an assessment of the role of two of the most prominent historical figures in Upington, Reverend Adriaan Schroder and Abraham "Holbors" September. Ultimately, however, the focus falls on the current state of irrigation in the area. It is possible to distinguish between the approach of large commercial farming operations and that of smaller irrigation farming units to irrigation. Specific attention is given to the perceptions of irrigation farmers as far as the policies and legislation pertaining to water issues is concerned. This study will hopefully provide the Department of Water and Environmental Affairs(DWEA), //Khara Hais Local Municipality and organised agriculture with some recommendations on efficient integrated water management strategies. It might well be of value to other municipalities who are experiencing similar problems. The aim has been to identify typical problems and potential disputes between water management institutions and relevant role-players. / Thesis (Ph.D. (Public Management and Administration))--North-West University, Vaal Triangle Campus, 2010.

This study is an investigation into water management policies in South Africa, their effect on water users and the perceptions users have of these policies. The investigation begins with an exposition of concepts such as water demand management (WDM), as well as integrated water resource management (IWRM). A sub-discourse of the main theme is the societal tendency to neglect its common property. Garret Hardin's groundbreaking observations on the "tragedy of the commons" (1968) are explored in an effort to locate issues of relevance in effective water management strategies. In contemplating the commons, it is evident that aspects of morality and ethics are involved. The morality of a society be it in a global or national context, seems to manifest itself in legislation and policies, and in the way these are implemented. The relevance of good governance, hydropolitics and sustainable development is also discussed to provide the necessary theoretical background to an understanding of the relationship between consumers and the water commons. Access to safe drinking water is protected in the Constitution of the Republic of South Africa Act, 108 of 1996. Flowing from the government's obligation to take reasonable legislative and other measures to achieve the progressive realisation of fundamental human rights stipulated in section 27(2) of the Constitution, the challenge since 1994 has been to provide access to water for all inhabitants and to manage the available water resources effectively. Furthermore, the objective of subsequent water legislation such as the National Water Act, 36 of 1998 and regulatory plans, like the National Water Resource Strategy has been to incorporate international trends in water governance. The Department of Water and Environmental Affairs (DWEA) divided South Africa into 19 regions, called water management areas (WMA). In this study, attention is focused on what constitutes a catchment and how a catchment management agency (CMA) governs its water resources. A description is provided of the functions of water user associations (WUAs) and how ththe Lower Orange Catchment Management Area is, for example, the blueprint from which stakeholders develop their goals. In this study, the water situation in the Lower Orange Water Management Area is under scrutiny. The focus is on the three main institutional components of water management (the Lower Orange catchment management, the Upington Islands Water User Association [UIWUA] and the //Khara Hais Local Municipality). The progress of the establishment of the Lower Orange Catchment Management Agency is outlined over a period of five years. Meanwhile, the Upington Islands Water User Association was developed and this has grown in stature. The work being done by these institutions is investigated by looking at grassroots effects, especially in respect of irrigation activities. The unique water management circumstances of the //Khara Hais Local Municipality are then investigated along with the plans outlined in their Integrated Development Plan {lOP) and their Water Services Development Plane Internal Strategic Perspective (ISP) of(WSDP). Because local irrigation operations consume most of the available surface water in the Lower Orange Water Management Area, irrigation farmers and their activities warrant closer attention. A historical overview is given of the development of irrigation in the region followed by an assessment of the role of two of the most prominent historical figures in Upington, Reverend Adriaan Schroder and Abraham "Holbors" September. Ultimately, however, the focus falls on the current state of irrigation in the area. It is possible to distinguish between the approach of large commercial farming operations and that of smaller irrigation farming units to irrigation. Specific attention is given to the perceptions of irrigation farmers as far as the policies and legislation pertaining to water issues is concerned. This study will hopefully provide the Department of Water and Environmental Affairs(DWEA), //Khara Hais Local Municipality and organised agriculture with some recommendations on efficient integrated water management strategies. It might well be of value to other municipalities who are experiencing similar problems. The aim has been to identify typical problems and potential disputes between water management institutions and relevant role-players. / Thesis (Ph.D. (Public Management and Administration))--North-West University, Vaal Triangle Campus, 2010.

This dissertation has focused on studying the effect of four glycine derivatives on the solid state properties of mannitol, glycine, and sucrose when freeze dried into blended mixtures. The primary goal was to assess their value for use in the stabilisation of vaccines in the solid state, by examining key physical and chemical characteristics, which have been documented to be beneficial to the stabilisation of biopharmaceutical formulations. The novel excipients; dimethyl glycine, and trimethyl glycine, were shown to retard the crystallisation and increase the overall glass transition temperature, of mannitol, when freeze dried as evidenced by DSC and Powder X-ray diffraction. Mannitol’s glass transition temperature increased from 100C to 12.650C and 13.610C when mixed with methyl-glycine and dimethyl glycine respectively. The glycine derivatives did not show the same effect on sucrose which remained amorphous regardless of the concentration of the other excipient. The different behaviour with the sucrose system was thought to be due to relatively high glass transition temperature of sucrose. Conversely glycine remained highly crystalline due it’s relatively low glass transition temperature. The novel excipient formulations were also assessed for their effect on the aggregation of the adjuvant aluminium hydroxide when freeze dried by Dynamic Light Scattering (DLS).The formulations containing the glycine derivatives all caused a decrease in the aggregation size of the adjuvant from ~26 μm, to 185 nm in the presence of methyl glycine. The effects of lysozyme and viral antigen on the adjuvants were also examined showing that the addition of the virus did not affect the size of the aggregates formed, however lysozyme showed significant decreases in the aggregates formed. Examination of the freezing method were also made showing that faster freezing rates produced smaller aggregates of the adjuvant. When investigating the rate at which the excipients lost water during secondary drying there was evidence of the formation of hydrates of glycine, trimethyl glycine, and mannitol has shown that the glycine derivatives have attributes which would be beneficial in stabilising vaccines in the solid state when freeze dried.

This study investigated the development and implementation of methods and procedures as generic administrative function, with specific reference to issuing drivers licences in the Driving Licence Testing Centre of the Madibeng Municipality. The contribution of the study to the discipline, Public Administration, is found in the basic framework for the development of standard operating procedures. Furthermore, a set of standard operating procedures to issue drivers licences was developed. In essence, the systems theory inspired the design of the basic framework for the development of standard operating procedures, while the phases of the ADDIE instructional design model simplified the drafting of the standardised procedures to issue drivers licences. Although the empirical data collection commenced with a quantitative research methodology, a qualitative dimension was required to fully understand the problem why the Driving Licence Testing Centre at the Madibeng Municipality lacks contemporary and relevant standard operating procedures to issue drivers licences. A mixed methods research design was eventually adopted to explore the phenomenon because a second research method was needed to strengthen the primary research method. Data was initially collected through a questionnaire, and follow-up personal interviews were conducted to clarify issues that were not responded to or unclear from the self-administered questionnaires. This conforms to pragmatism - the research philosophy adopted for this study because predetermined research questions dictated the path towards realising the research objectives. Since this study utilised a mixture of qualitative and quantitative research designs, the research methodology was shaped by various strategies, techniques and data collection instruments, such as literature reviews, document analyses to draft the standardised procedures, case study (Driving Licence Testing Centre of the Madibeng Municipality), a structured questionnaire and semi-structured personal interviews. In this study, the administrative generic function of determining and revision of methods and procedures was referred to as ‘methods and procedures’. Within the context of Public Administration, the study revealed that methods and procedures specify the sequence, processes and techniques necessary to execute certain actions and operations during service delivery. Moreover, it states how tasks must be exercised within the public sector, as well as indicate who must take action. Consequently, methods and procedures are built into all public service activities, regardless whether these are administrative, functional or auxiliary activities. It was concluded that methods and procedures form an indispensable part of any public institution’s activities. However, the study focused on methods and procedures to issue drivers licences at the Driving Licence Testing Centre of the Madibeng Municipality. The study realised its overall aim when recommendations were made to the Driving Licence Testing Centre of the Madibeng Municipality of how to develop and implement standard operating procedures to issue drivers licences. In essence, it was recommended that the basic framework for the development of standard operating procedures be applied when updating and/or developing methods and procedures. Moreover, it was recommended that the set of newly developed standard operating procedures be adopted and implemented. It was also suggested, amongst other proposals, that the management and the staff at the Centre engage from the initial stages in the procedure development process, that clear steps and instructions of how to reach organisational short-term objectives, be specified, and caution be taken by the Madibeng Municipality against the implementation of an overly multifaceted internal control system at its Driving Licence Testing Centre. / Department of Public Administration and Management / D.Admin. (Public Administration)

Discontent with preaching as mode of communication is the problem statement of this study. The authoritative nature of deductive preaching is mirrored by the exploratory, "discovery nature" of inductive models, emphasizing how dialogical preaching is enhanced by incorporating inductive elements into preaching. Meaning production and levels of meaning were studied, and a hermeneutical model for Pentecostal churches were proposed. Dialogical preaching as attitude and principle as well as method was looked at, and the role of interactive participative communication in the dialogic process was described. Special emphasis was placed on the Parable, the metaphor and narrative preaching as models for inductive preaching, and the development and phases of the "plot" was examined. Bridging models between inductive and deductive styles were explored, while two dialogical tools for preparation of sermons were designed. / Philosophy, Practical and Systematic Theology / Th.M. (Practical theology)

The purpose of this study was to explore the practices and processes executed by middle managers as practitioners during the implementation of strategy. In order to do that, this study investigated the problem of strategy implementation, analysed existing literature, identified the gaps, and explored the roles of middle managers in terms of strategy practices and processes, specifically in the South African Defence Evaluation and Research Institutes (DERI) context. Resources, time and effort are applied to formulating strategy but less of these to the execution of the strategy which includes the emotions, motivations and actions that are intangible during the implementation of strategy. The study therefore attempts to answer the following research question: What practices and processes are employed in strategy implementation in DERIs in South Africa? The literature study was undertaken with the objective of mapping the research problem and to highlight, through critical discussion, the latest work done on the subject of this study. The gap in relation to research work was identified and the contribution is clear that not much work has been done in this environment. Research is a systematic process where information on a specific topic is gathered in order to increase understanding of that phenomenon. A qualitative study was performed and data was obtained from several institutes through interviews, documents and questionnaires in order to build a rich database that could be analysed for the required output. Engagement with the first level of management as well as the next level management teams ensured that a representative population group was used during this study. The data was organised, categorised, interpreted, identified, synthesised and generalised. The quotations identified from the text were coded through inductive coding and grouped into categories until a logical theme, category and concept was formed. The objective of this research was to investigate, identify and understand what the strategy practices and processes are that make highly technical and scientific institutes execute strategies successfully. The study provided insight into and clarity on the complexity of the strategy implementation process as executed by middle managers, particularly in the South African context. The link was explored between formulation and implementation as applied by middle managers as practitioners and the practices and processes in use were identified. It was demonstrated that the outcome of this research is applicable to the research problem and also provides an understanding of the phenomenon, namely strategy practices and processes in use at the Defence Evaluation and Research Institutes. It can therefore be concluded that the research objective was achieved. / Business Management / D.B.L.

Apresentamos um modelo matemático geral, baseado na teoria de Cosserat para estruturas flexíveis unidimensionais, em regime de deslocamentos finitos e sujeitas a restrições unilaterais. Ao modelo geral agregamos a hipótese de inextensibilidade e, desprezando os efeitos do cisalhamento e das forças inerciais, formulamos o problema variacionalmente tanto na forma cinemática quanto em Lagrangiano Aumentado. Para esta última formulação, construímos aproximações por elementos finitos de Galerkin e utilizamos um algoritmo do tipo Uzawa para a solução do problema aproximado. Apresentamos estudos numéricos com o intuito de avaliar a formulação, validar o algoritmo de solução e exemplificar possíveis aplicações práticas do modelo. Buscando viabilizar uma análise numérica, realizamos uma linearização consistente do modelo geral apresentado anteriormente, produzindo um modelo em regime de pequenos deslocamentos e deformações, descrito no espaço tridimensional. Para este problema, introduzimos uma aproximação por elementos finitos mistos estabilizados, adicionando à formulação de Galerkin formas residuais de mínimos quadrados provenientes das equações de equilíbrio. Provamos que esta formulação atende às condições suficientes para existência e unicidade de solução, independente da esbeltez da estrutura. Apresentamos estimativas de erro indicando taxas de convergência e resultados numéricos comprovando tais taxas. Apresentamos algumas aplicações dos modelos ao estudo de estabilidade de dutos aquecidos e enterrados, na análise da estabilidade de armaduras de risers e umbilicais e, na área biológica, apontamos as possibilidades de suas utilizações na modelagem de moléculas de ADN.