The availability of water can be considered as one of the key ingredients to the human life, yet this resource remains scarcely available to those living in the rural parts of Africa. When water does present itself, it is often impure and requires extensive treatment. Water treatment systems, particularly those capable of treating water in rural areas, are currently areas of research and entrepreneurship focus, making a number of potential solutions available, and other still coming in. Unfortunately, these systems are not always capable of performing in particular socio-cultural and economic contexts, or are often deployed in the wrong rural areas. Therefore these systems do not perform at their optimal level of design. Rural areas in Africa have different socio-cultural and economic context from each other, and this needs to be taken into account if one is going to select the right water treatment system for a particular area. Using industrial engineering tools, two water treatment system selection models; an Additive Analytic Hierarchy Process model and a Fuzzy Logic based model, are presented and then integrated. These models take into account the context of selected rural area by pitting available water purification systems against selected criteria to determine if it is the right fit for the rural area considered. Both models are then pitted against each other to determine which is more adept at selecting the appropriate water purification system. Three water treatment alternatives were considered after an analysis was conducted on the available solutions on the market. The water treatment systems under consideration were the Biosand Filter with Zeolites (BSFZ), the Silver Impregnated Porous Pot, and A Borehole system. Makwane, a rural village in Limpopo, South Africa was used as a case study to demonstrate the application of the selection models. The BSFZ was selected as the ideal water treatment system to be implemented in Makwane / Dissertation (MEng)--University of Pretoria, 2016. / Industrial and Systems Engineering / MEng / Unrestricted

The need for this research stems from the need for organisations to develop, nurture and grow managers into leadership positions and identifying the factors that positively contribute to this growth within organisational hierarchy. In this study, leadership and management skill requirements are conceptualised as being layered or segmented, and are described using a one-by-one grid matrix. Based on this grid, this study utilises up to of five categories of management and leadership requirements: managing oneself, managing others, managing teams, managing functions and managing companies. The model is then tested in a sample of ninety two (92), junior, midlevel, and senior managers, within an organisation hierarchy. A quantitative research methodology was utilised, with self-administered questionnaires, developed to test for management and leadership dimensions among employees within an organisational hierarchy. Based on this the study explores those factors that contributed the transitioning of employees from managers into leadership positions. Findings support the element of the model through the emergence of the leadership skill requirement categories. Findings also support the second portion of the model in that different categories of leadership skill requirements emerge at different organisational levels, and that jobs at higher levels of the organisation require higher levels of all leadership skills. In addition, although certain skill requirements are important across organisational levels, certain strategic skill requirements only fully emerge at the highest levels in the organisation. However on management skill levels, it was found to be not conclusive, the findings show that management skill requirements are important across organisational levels, irrespective of the employee’s level in the hierarchy, be it at the lower or highest levels in the organisation. Lastly it shows that for management and leadership development, individual and personal traits are not as critical for managers and management development, however they are extremely critical for leaders and leadership development, as one transitions up the hierarchy within an organisation. This proved to be a valuable tool for conceptualising leadership skill requirements across organisational levels. Copyright / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted

No description available.

The cement industry represents nearly 8% of fossil fuel and industrial emissions making it a key area of focus for policymakers around the world. Much of the current effort in cement manufacturing has focused on energy efficiency and material substitution with more recent work focused on carbon dioxide uptake and recycled concrete aggregate use to address greenhouse gas emissions and material conservation, respectively. Currently, no meaningful approach exists for practitioners or policymakers to address greenhouse gas emission reduction for cement manufacturing that incorporates the concepts of material conservation. The Carbon Hierarchy is proposed as a successive stage hierarchy to address this gap. This work is logically and empirically validated using a newly constructed model incorporating the key levers of service life extension, thermal energy decarbonization, limestone substitution, mineral component (MIC), carbon dioxide uptake with consideration for the process flow that incorporated reintroduction of end-of-life (EOL) concrete as raw material or clinker substitution in cement manufacturing and as potential downstream use as aggregate. The Carbon Hierarchy proposed in this research could guide decisions to significantly reduce greenhouse gas emissions for the cement industry while ensuring material conservation. / Thesis / Doctor of Philosophy (PhD)

Among sociological studies in South Asia, frequent reference is made to caste as one of the greatest motivating factors in establishing, reinforcing, and creating social structure. This system of social hierarchy has, however, undergone drastic shifts and changes over the past decades (Dirks, 2001: 5) resulting in 'caste' as a term used to systematize concepts of social identity, community, and organization in India. The Brahmin caste, in particular, has undergone drastic changes as a result of social and political influence from without as well as from within, resulting in a conflict of identity (Bairy, 2010: 233).As a direct result of this conflict of caste identity, many individuals respond, act, and interact in ways that confirm, reject, or (re)establish their own individual identity within the greater scheme of their caste. The current study will examine specific ways in which Telugu Brahmins use linguistic markers to index socially acceptable, cultural ideologies. It will be explained how the use of lexical borrowings, markers of politeness and honorification, and emphatic aspiration index historical ideologies of Brahmin-ness. In indexing these ideologies, Brahmins identify with and associate their own actions in relation to traditional notions of those qualities assumed to be inherent in the Brahmin caste. Furthermore, meta-linguistic discourse will be examined, showing that recognition, acknowledgment of, and (mis)interpretation of a 'Brahmin register' is used to both mark intra-caste solidarity and reinforce social stereotypes about the caste.

I used multivariate, hierarchical analyses to examine the relative influence of watershed-, riparian- and channel-scale environmental characteristics on catch per unit effort (CPUE: fish/angler-hour) and species composition of sport fisheries in Mississippi wadeable streams. Partial canonical correspondence analyses indicated that riparian-scale variables (31.1%) explained more variation in sport fish relative abundances compared to watershed-scale (24.4%) and channel-scale variables (18.9%). Largemouth bass M. salmoides and longear sunfish Lepomis megalotis were more abundant in smaller-watershed streams with dense forest cover and greater woody debris, alkalinity and diverse substrates. Spotted bass M. punctulatus and bluegill L. macrochirus were more abundant in larger-watershed streams with moderate to dense forest cover yet more open riparian canopies. Regional-scale characteristics also influenced relative abundances of these fisheries. Total CPUE, total bass CPUE and largemouth bass CPUE were greatest in watersheds draining the Blackland Prairie-Flatwoods compared to other level III ecoregions. This ecoregion contains fertile soils that influence stream productivity, because alkalinity tends to be large in forested streams draining this ecoregion. I developed and validated watershed-scale models and found that percentage forest cover, stream density, total road density and primary highway density predicted mean total CPUE, mean total sunfish CPUE and mean total bass CPUE accurately (Sign tests comparing observed versus predicted mean CPUE, P > 0.05). The models were precise (R2 > 0.71), explaining 83%, 71% and 80%, respectively, of variation in mean total CPUE, mean total sunfish CPUE and mean total bass CPUE from independent data. Species-specific models performed poorly, suggesting biotic relationships may hinder development of meaningful habitat models for species. My study supports forest conservation to sustain sport fisheries in Mississippi’s wadeable streams. Forests mediate sediment and nutrient loading to stream channels, influence hydrology and channel morphology and provide woody habitat for sport fish and their forage base (benthic macroinvertebrates). My small sample size was small; (N = 13 reaches), thus caution is advised before engaging in comprehensive management of wadeable streams based on my results. Nevertheless, my watershed models can be applied at very low cost using a GIS or topographic maps to identify reaches state-wide that support wadeable stream sport fisheries.

No description available.

Dans ce travail nous étudions la complexité de certains fragments du mu-calcul selon deux points de vue: l’un syntaxique et l’autre topologique. Dans la première partie nous adoptons le point de vue syntaxique afin d'étudier le comportement du mu-calcul sur des classes restreintes de modèles. Parmi d'autres résultats, nous montrons en particulier que sur les modèles transitifs toute propriété définissable par une formule du mu-calcul est définissable par une formule sans alternance de points fixes. Pour ce qui concerne la perspective topologique, nous montrons d'abord que sur les modèles transitifs la logique modale correspond au fragment borélien du mu-calcul. Ensuite nous donnons une description effective des hiérarchies de Borel et de Wadge d'un sous-fragment sans alternance de cette logique sur les arbres binaires et vérifions que pour ce fragment les points de vue topologique et syntaxique coïncident. / In this work we study the complexity of some fragments of the modal mu-calculus from two points of view: the syntactical and the topological. In the first part of the dissertation we adopt the syntactical point of view in order to study the behavior of this formalism on some restricted classes of models. Among other results, we show that on transitive transition systems, every mu-formula is logically equivalent to an alternation free formula. For what concerns the topological point of view, we first prove that on transitive models, the modal logic is exactly the Borel fragment of the modal mu-calculus. Then we provide an effective description of the Borel and Wadge hierarchies of a sub-fragment of the alternation free fragment of the mu-calculus on binary trees. Finally we verify that for this fragment the syntactical point of view and topological point of view coincide.

Le monde industriel est sans cesse confronté à des problèmes de choix. Une multitude de critères doit être pris en compte dans la résolution de ces derniers. Face à ces situations, les outils d’aide à la décision prennent tout leur sens. Nous utiliserons ici la méthode Analytic Hierarchic Process dans le domaine de la Production et plus particulièrement dans le cadre de l’ordonnancement d’une ligne de production de prothèses cardiovasculaires. Le paramétrage initial de cette méthode fait appel à l’évaluation d’un expert. Bien que ce dernier ait les connaissances nécessaires pour faire un paramétrage convenable, il n’en reste pas moins humain et introduira, même involontairement, une partie subjective dans ses décisions. L’ordonnancement en résultant ne sera donc pas forcément optimal. La réduction de cette subjectivité passe par l’utilisation d’une méta heuristique, de type algorithme génétique, pour améliorer ce paramétrage par l’exploration de solutions voisines à celles proposées par l’expert. / The industrial world is continually faced with problems of choices. Multitude of criterion must be taken into account in resolving them. Faced with these situations, the decision making tools give solutions. We will use the Analytic Hierarchy Process in the production field and especially in the scheduling of a cardio vascular prosthesis production line. The initial parameterization of this method involves the evaluation of an expert. Although he has the required knowledge to make a fitting setup, he is no less human and he will bring even unintentionally a subjective part in his decision. The resulting scheduling will therefore not necessarily be optimal. The reduction of the subjectivity can be done using a metaheuristic method, of genetic algorithm type, to improve this parameterization by exploring neighbouring solutions compared to those proposed by the expert.

"Modern computer applications from business decision support to scientific data analysis use visualization techniques. However, visual exploration tools do not scale well for large data sets, i.e., the level of clutter on the screen is typically unacceptable. To solve the problem of cluttering at the interface level, visualization tools have recently been extended to support hierarchical views of the data, with support for focusing and drilling-down using interactive selection. To solve the scalability problem, we now investigate how best to couple such a near real-time responsive visualization tool with a database management system. Our solution proposes a framework containing three major components: hierarchy encoding, caching and prefetching. Since the direct implementation of the visual user interactions on hierarchical data sets corresponds to recursive query processing, we have developed a hierarchy encoding method, called the MinMax tree, that pushes the on-line recursive processing step into an off-line precomputation step. The MinMax encoding scheme allows us to map the hierarchy to a 2-dimensional space and the recursive navigation operations at the interface level to 2-dimensional spatial range queries. These queries can then be answered efficiently using spatial indexes. To compliment this encoding scheme we employ a caching strategy that exploits user navigation characteristics to cache the nodes having high probability of being referenced again. Based on user characteristics we choose to implement two replacement policies one which exploits temporal locality (LRU) and the other exploits spatial locality (Distance). Also, to enhance the performance of the cache we propose using a prefetching mechanism that predicts and prefetches future user requests into the cache. Together the components form a comprehensive framework that scales the visualization tool to support navigation operations over large data sets. The techniques have been incorporated into XmdvTool, a free software package for multi-variate data visualization and exploration. Our experimental results quantify the effectiveness of each component and show that collectively the components scale the XmdvTool to support navigation operations over large data sets. Mainly, our experimental results show that together the components can achieve 63\% to 96\%reduction in response time latency even with limited system resources."