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Thesis (MPA.) -- University of Limpopo, 2020 / The Low-cost housing delivery programme was launched at the dawn of democracy under the negotiated housing policy in year 1994 with the aim of addressing the backlog in housing provisioning. The programme was also meant to address the past injustices. The democratic government launched Batho Pele Principles in the year 1997 as a framework within which public services would be provided. The purpose of the study was to evaluate the impact of adherence to Batho Pele Principles in the provisioning of low-cost housing services by the Cooperative Governance Human Settlements and Traditional Affairs Department in Limpopo Province.The qualitative research methods were applied to generate data relevant for the study. The study involved the reviewing of secondary data available in the department in the form of Annual performance plans, Annual performance reports, Service delivery improvement plan, Service standards, Citizens’ report and minutes taken during departmental self-evaluation meetings. The findings reveal that CoGHSTA underperformed on delivery of low-cost houses targets for three consecutive years. The underperformance was attributed to protracted procurement of service providers and non-approval of application forms due to insufficient/irrelevant information provided by the applicants. Inadequate consultation and involvement of beneficiaries prior to and during the implementation of low-cost housing projects appeared to be a major issue of concern. The adherence to Batho Pele Principles was not adequately implemented. The study recommends that enhancement of housing consumer education will help a great deal in reducing the number of application forms with insufficient/irrelevant information being submitted for processing. The appointment of service providers during the year preceding the implementation year would provide ample time for planning.

In this dissertation, a novel two-phase switched reluctance machine (SRM) with a stator comprised of E-core structure having minimum stator core iron is presented for low-cost high-performance applications. In addition, three new magnetic structures for the E-core SRM comprising two segmented stator cores or a monolithic stator core are proposed for good manufacturability, mechanically robustness, ease of assembly, and electromagnetic performance improvement. Each E-core stator in the segmented structure has three poles with two small poles at the ends having windings and a large center pole containing no copper windings. The common stator pole at the centers in the segmented E-core is shared by both phases during operation. Other benefits of the common poles contributing to performance enhancement are short flux paths, mostly flux-reversal-free-stator, constant minimum reluctance around air gap, and wide pole arc equal to one rotor pole pitch. Therefore, two additional common poles in the monolithic E-core configuration are able to significantly improve efficiency due to more positive torque and less core loss by the unique design. Using a full MEC analysis, the effect of the common-pole structure on torque enhancement is analytically verified. Efficiency estimated from the dynamic simulation is higher by 7% and 12% at 2000 rpm and by 3% and 7 % at 3000 rpm for the segmented and single-body SRMs, respectively, compared to a conventional SRM with four stator poles and two rotor poles. The new E-core SRMs are suitable for low-cost high-performance applications which are strongly cost competitive since all the new E-core SRMs have 20% cost savings on copper and the segmented E-core SRMs have 20% steel savings as well. Strong correlation between simulated and experimentally measured results validates the feasibility of the E-core common-pole structure and its performance. A simple step-by-step analytical design procedure suited for iterative optimization with small computational effort is developed with the information of the monolithic E-core SRM, and the proposed design approach can be applied for other SRM configurations as well. For investigating thermal characteristics in the two-phase single-body E-core SRM, the machine is modeled by a simplified lumped-parameter thermal network in which there are nine major parts of the motor assembly. / Ph. D.

Highway safety has been a priority for many years now. A system-wide crash analysis is a practical solution when only a limited budget is available for improving safety of highways. A systematic approach, in contrast to a hotspot analysis, allows for a widespread installation of lower-cost countermeasures across the highway network. This study focuses on the safety evaluation of a particular facility type, urban freeway off-ramps, in terms of its geometric and traffic characteristics. 144 off-ramp segments in Richmond, VA were evaluated based on the crash data available from 2011 to 2015. A statistical model was developed that relates crashes to the geometric and traffic characteristics of each off-ramp segment. A test for independence was performed to identify if a statistically significant difference existed between type of collision and severity of crashes with respect to ramp geometry and traffic control. Significant geometric and traffic variables were then identified from the model and independence test to assist in the selection of low-cost countermeasures. AADTs of both freeways and off-ramps were found to be the most statistically significant variables. Installation of advance warning signs for better traffic management near the freeway diverge area and clearing roadsides of fixed objects to reduce rear-end collisions are low-cost solutions for crashes on urban off-ramps in the study area. The results of this study demonstrate an approach to safety evaluations that could support transportation planners and agencies in identifying system-wide locations to install or apply appropriate low-cost countermeasures. / Master of Science

The random wetlay process is used to make fiber-reinforced thermoplastic sheets that can be compression molded into composite panels at little cost. By utilizing these composite panels as the facesheets of honeycomb sandwich structures, it is possible to greatly increase the bending stiffness of the composite without adding significant weight. The random wetlay composite facesheets used in this research consisted of 25% E-glass fibers and 75% PET by weight. The thickness uniformity of the facesheets was difficult to control. The core of the sandwich structure was HexWeb&174; EM. Three low-cost adhesives were examined for secondarily bonding the facesheets to the core: polyurethane glue; epoxy paste; and 3M Scotch-Grip&174; plastic adhesive. The polyurethane glue mixed with Cab-O-Sil filler was easiest to apply and provided the largest flatwise tensile strength. Mathematical models were developed to predict the static behavior of sandwich beams and plates in bending. Three-point bend tests were performed on a sandwich beam in accordance with ASTM C 393. A sandwich plate simply supported along two opposite edges and free along the other two edges was subjected to a line-load using weights and a wiffle tree arrangement. An effective facesheet modulus and Poisson's ratio were found by comparing the measured displacements to the sandwich plate theory. The shadow moiré technique was used to visualize the displacement of the line-loaded sandwich plate. The overall shape of the displacement was very similar to the shape predicted by the sandwich plate theory. / Master of Science

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: It is well known that South Africa has a major housing backlog and that the population is growing every year. Consequently, more people are left homeless, without the finances to acquire a minimum standard house. The official backlog in 2012 was defined as 2.1 million units, of which 1.1 million households lived in informal settlements in South Africa. The purpose of this study is to develop a multi-criteria assessment tool that will help a developer to choose between housing systems that can be used in low cost housing developments. Essentially, the tool will aid a developer to allocate funding more appropriately and effectively to develop sustainable communities. The research followed a procedure of identifying challenges experienced in the low cost housing industry, identifying the important factors to consider when assessing low cost housing systems and finally selecting a multi-criteria decision-making model to select a system. The important factors that need to be considered for this study were gathered from literature and industry experience through using the interviewing technique for data collection. The factors identified will be assessed using the multi-criteria decision-making model, called the Evidential Reasoning Approach. This study focuses on housing systems as a whole. Specific attention is given to walling systems, but not to other elements such as the foundations and roofs. The primary factors identified are cost, time, quality, environmental performance, density, alteration capability, resource availability and additional features. These factors were then used to develop a userfriendly assessment tool for choosing between housing systems for the low cost housing market. In conclusion this assessment tool will be available to public and private role players who intend to develop a low cost housing settlement. However, this assessment tool has some imperfections. These are discussed at the end of this study and show how they influence this model. / AFRIKAANSE OPSOMMING: Dit is algemeen bekend dat Suid-Afrika „n groot behuisings agterstand het en dat die bevolking jaarlikse groei. Die amptelike behuisings agterstand in 2012 was gedefinieer as 2.1 miljoen eenhede, waarvan meer as 1.1 miljoen van hierdie huishoudings in informele nedersettings in Suid-Afrika geleë is. Die doel van hierdie studie is dus om „n mulit-kriteria assesserings instrument te ontwikkel wat „n ontwikkelaar sal help om tussen behuisings sisteme te kies, wat vir lae koste behuising ontwikkelings gebruik kan word. Gevolglik , sal hierdie instrument „n ontwikkelaar help om befondsing meer toepaslik toe te ken en om doeltreffende en volhoubare gemeenskappe te ontwikkel. Die navorsings prosedure het begin deur uidagings in die lae koste behuising bedryf te identifiseer, asook die belangrike faktore wat oorweeg moet word as behuisings stelsels beoordeel moet word. „n Multi-kriteria besluitnemings model is gekies wat toepaslik is op hierdie studie. Die belangrike faktore wat in ag geneem moet word, is geïdentifiseer deur literatuur, en industrie ondervinding, deur gebruik te maak van onderhoude om data in te samel. Die kriteria wat geïdentifiseer is sal beoordeel word met behulp van die multi-kriteria besluitnemings model, naamlik Evidential Reasoning Approach. Die kriteria wat gebuik is in hierdie studie het gefokus op die behuisings stelsel as ʼn geheel. Alhoewel spesifieke aandag gegee is aan die mure van die stelsels was ander elemente, soos die dakke en fondamente nie bespreek nie. Die primêre faktore wat geïdentifiseer is, is koste, tyd, kwaliteit, omgewings werkverrigting, digtheid, aanbouings vermoë, beskikbaarheid van hulpbronne en bykomende funksies. Hierdie faktore word gebruik om „n keuse te maak tussen behuisings stelsels vir die gebruik vin die lae koste behuising mark. Die faktore word voorgestel as „n gebruikers vriendelike assesserings instrument. Ten slotte behoort hierdie assesserings intrument beskikbaar te wees aan oopenbare en private belangstellendes wat beoog om „n lae kost behuising nedersetting te ontwikkel. Hierdie assesserings instrument het wel „n paar tekortkomming, wat aan die enide van die studie bespreek word, asook hoe hierdie terkortkomming die model kan beïnvloed.

In Feldstudien konnte häufig mittels der Low–Cost Hypothese gezeigt werden, dass normatives Verhalten von den dafür aufzuwendenden Kosten abhängt. Doch hängt die Durchsetzung einer Norm ebenfalls von der Höhe der Kosten ab? Die Gültigkeit der Low – Cost Hypothese bei diesen kollektiven Gütern zweiter Ordnung ist bislang im Feld wenig erforscht. In unserer Studie wird die Durchsetzung sozialer Normen anhand nachbarschaftlicher Kontrollen analysiert. Es werden Daten einer postalischen Befragung von 631 Personen in Leipzig aus dem Jahr 2001 ausgewertet: Der Zusammenhang zwischen der Befürwortung sozialer Kontrollen und der Bereitschaft, soziale Kontrollen tatsächlich an sich zu erdulden, wird mit steigenden Kosten der zu erduldenden Kontrollhandlungen schwächer. Zudem lässt sich die Logik der Low – Cost Hypothese auf andere soziologische Konstrukte übertragen: Die Wirkung von Kriminalitätsfurcht und Autoritarismus ist umso weniger handlungsrelevant, je höher die Kosten der zu erduldenden Kontrollhandlungen sind. Diese Befunde demonstrieren die Gültigkeit der Low–Cost Hypothese im Zusammenhang mit kollektiven Gütern zweiter Ordnung. / In field studies, there is evidence that the occurrence of normative behaviour is dependent on its costs. This effect is known as the low cost hypothesis. However, is the enforcement of social norms as well dependent on its costs? So far, there has been little research on the validity of the low – cost hypothesis for so called second order collective goods. In our work, the enforcement of social norms is studied by means of analyzing social control in neighbourhoods. We use data of a mail survey conducted in 2001 in Leipzig, Germany, with 631 respondents: Correlations between approval of social control and willingness to tolerate social control personally decrease with increasing costs to tolerate these control activities. Additionally, the logic of low – cost is transferable to other sociological constructs: The effect of fear of crime and authoritarianism is the less relevant for tolerating social control activities, the higher the costs for these control activities. These empirical findings confirm the low cost hypothesis for the production of second order collective goods.

Les structures composites intégrant des transducteurs piézoélectriques au cœur de la matière sont utilisées pour leur capacité à modifier leurs propriétés mécaniques en fonction de l’environnement, à contrôler leur intégrité structurale et à interagir avec l’homme ou avec d’autres structures.Ce travail se concentre sur les phases de conception préliminaire des structures composites intelligentes. Ces phases ne représentent que 5% du coût total d’un projet, mais conditionnent 80% du coût final du produit. Les principaux problèmes rencontrés lors de ces phases de conception préliminaire portent sur la détermination des propriétés matériau des transducteurs piézoélectriques et des matériaux composites utilisés, de l'influence de l'emplacement des transducteurs dans la structure ainsi que de l’influence du processus de fabrication, de la température et des endommagements sur le comportement final des structures composites intelligentes.Dans le processus de fabrication développé à l’Université de Technologies Belfort-Montbéliard (UTBM), l’élément-clé est un produit semi-fini appelé “soft layer”. Cette couche permet d’intégrer le réseau de transducteurs piézoélectriques au cœur de la structure composite. Le processus de fabrication de la “soft layer” ainsi que celui des structures intelligentes sont abordés dans cette thèse.Afin de trouver des solutions aux problèmes décrits ci-dessus, deux méthodes de caractérisation de composites intelligents ou adaptatifs sont présentées et utilisées : la méthode dite Resonalyser et la méthode du temps de vol. Après des études expérimentales et une comparaison des résultats obtenus, la méthode du temps de vol a été choisie comme méthode principale en raison de son faible coût de mise en œuvre et du fait qu’il s’agit d’une méthode de caractérisation in-situ. De plus, une nouvelle méthode appelée méthode CMB, basée sur la méthode du temps de vol a été développée afin de pouvoir facilement et rapidement extraire les constantes élastiques, en particulier le coefficient de Poisson.Des analyses expérimentales de sensibilité appliquées aux composites adaptatifs ont été effectuées.Premièrement, l’étude de l’influence de l’emplacement des transducteurs démontre qu’il est nécessaire de tenir compte de la position de la “soft layer” dans la modélisation du comportement de produit final. La position de cette couche dans l’épaisseur du produit a une influence notable sur les fréquences propres ainsi que les amplitudes modales de la structure. Cependant, l’ajout de la “soft layer” n’accroît pas le taux d’amortissement de la structure finale; et sa position dans l’épaisseur n’a aucune influence sur ce taux d’amortissement. La propagation des ondes de Lamb à l’intérieur du composite n’est pas impactée par le “soft layer”.Deuxièmement, l’étude de l’impact du processus de la fabrication nous renseigne sur l’influence notable des divers paramètres de réglage du processus de fabrication sur le comportement final de la structure composite intelligente.Troisièmement, l’étude de l’influence de la température sur des structures constituées de différents matériaux composites montre que le module de Young du produit final décroît quand la température augmente. Mais la diminution du module de Young en fonction de la température est différente selon les et les types de matériaux et les directions des fibres, en particulier pour les structures composites unidirectionnelles. De plus, cette étude montre également la sensibilité de la méthode du temps de vol vis-à-vis de la température. Ce dernier point est par ailleurs consolidé par la comparaison avec des résultats obtenus par une méthode de caractérisation ex-situ standard : l'analyse dynamique de la mécanique (DMA).Enfin, l'étude de l'impact des dommages mécaniques fournit une assez bonne référence pour les recherches futures. De cette façon, il est clair qu’une méthode de temps de vol peut être utilisée dans la surveillance de la santé structurale. / The composite structures embedding piezoelectric implants are developed due to their abilities of modifying mechanical properties according to the environment, of keeping their integrity, of interacting with human beings or with other structures.This study is focused on the preliminary design stages of smart composite structures, which represent only 5% of the total costs of a project, whereas 80% of the life cycle cost are set during the preliminary study phases. The top few problems during the preliminary design of smart composite structures are addressed in this work such as the determination of the material properties of the piezoelectric transducers and composite material used, the influence of transducers location, manufacturing process, temperature and damage on the behavior of the smart composite structures.Due to the manufacturing process developed at the Université de Technologie de Belfort-Montbéliard (UTBM), the most important element is a semi-finished product called “soft layer”. This special layer is used to embed the transducers system into the composite structures. The manufacturing process of “soft layer” as well as the smart composite structures are compiled in this report.In order to solve the problems described above, two characterization methods of composite material (Resonalyser method and Time-of-Flight method (T-o-F method)), are introduced and discussed. After experimental studies and comparing the results of these two methods, the T-o-F method is chosen as the main method for the following studies due to the fact that it is a low-cost and in-situ characterization method. Furthermore, a new method based on the T-o-F method is developed to easily and quickly extract the elastic constants, in particular the Poisson’s ratio.Experimental sensitivity analyses applied to the smart composite structures are performed with respect to the problems describes above. First of all, the study of the influence of transducers location demonstrates that the "soft layer” cannot be neglected to model the behavior of the final product. In particular, the through-the-thickness position has an influence on the eigenfrequencies and the modal amplitudes. However, the "soft layer” does not increase the overall damping ratio of the final structures and the through-the-thickness position of the "soft layer” has no influence on the damping ratios. The Lamb wave propagation inside the composite material is not impacted by the "soft layer”. Secondly, the study of the impact of manufacturing process demonstrates that the impact of variability of parameters due to the manufacturing process is very important on the final response of the structure. Thirdly, the study of the influence of temperature on different kinds of smart composite structures proves that when temperature increases, the Young’s modulus of the smart composites decreases. But the attenuation of Young’s modulus according to temperature is different along different fiber directions, especially for the unidirectional composite structures. Furthermore, in this study, the sensitivity of Time-of-Flight method with respect to temperature is well proved by comparing the results with a traditional method like Dynamic-Mechanical Analysis (DMA). Last but not least, the study of the impact of the mechanical damage gives a quite good reference for the future investigations. Along this way, it is possible to use a Time-of-Flight method in Structural Health Monitoring. In addition, some smart composite structures manufactured by the research team are given and their potential applications are discussed.

In South Africa issues regarding the dissatisfactory delivery of low-cost housing developments are well known. Low-cost housing has generally been delivered in a manner which attempts to address housing backlogs, instead of focussing on establishing quality environments and sustainable communities. In order to address the current deficient approaches to low-cost residential development, a literature and empirical investigation was conducted with the purpose of exploring the South African status quo. Issues for improvement were researched within the existing knowledge base. The literature reviewed for this study encompassed government literature, policies and legislation as well as work from both national and international authors from a variety of fields, given the diverse nature and multiple impacts related to housing development. These literary works provided evidence to the conclusions drawn and informed the recommendations made accordingly. The empirical research conducted included several structured interviews, the distribution of questionnaires and the evaluation of various South African case studies. Empirical results added a quantitative measure to the evidence provided by the literature study and thus offered further conclusions and recommendations. The recommendations made were categorised according to their contribution to planning, management and design. It is believed that the adoption of these preliminary recommendations may greatly improve the housing delivery process and quality of life experienced by low-income beneficiaries. The issues covered in this study include research, conclusions and recommendations on: * Investigating the South African status quo with regard to housing policies and legislature. * Identifying the merits of historical theoretical models and their value in modern day housing development. * Discussing the importance of a locally focussed development approach with regard to the role of local municipalities versus provincial authorities in low-cost residential development. * Identifying the value of low-cost housing in local economic development and sustainable socio-economic growth. * Discussing the role of community participation in delivering sustainable neighbourhoods and communities. * Investigating the need for higher density development with specific reference to the integration of various housing typologies. * Exploring the relevance and benefits of alternative construction materials in low-cost residential development. * Exploring the informal backyard rental sector. * Exploring the approaches followed in South African case studies of varying successes in various provinces. It should be noted that the research conducted for this study, the conclusions drawn and the recommendations made provide substantial value, but are all mainly provided as preliminary concepts to be elaborated in a future PhD study. / Thesis (MArt et Scien (Urban and Regional Planning))--North-West University, Potchefstroom Campus, 2013

In South Africa issues regarding the dissatisfactory delivery of low-cost housing developments are well known. Low-cost housing has generally been delivered in a manner which attempts to address housing backlogs, instead of focussing on establishing quality environments and sustainable communities. In order to address the current deficient approaches to low-cost residential development, a literature and empirical investigation was conducted with the purpose of exploring the South African status quo. Issues for improvement were researched within the existing knowledge base. The literature reviewed for this study encompassed government literature, policies and legislation as well as work from both national and international authors from a variety of fields, given the diverse nature and multiple impacts related to housing development. These literary works provided evidence to the conclusions drawn and informed the recommendations made accordingly. The empirical research conducted included several structured interviews, the distribution of questionnaires and the evaluation of various South African case studies. Empirical results added a quantitative measure to the evidence provided by the literature study and thus offered further conclusions and recommendations. The recommendations made were categorised according to their contribution to planning, management and design. It is believed that the adoption of these preliminary recommendations may greatly improve the housing delivery process and quality of life experienced by low-income beneficiaries. The issues covered in this study include research, conclusions and recommendations on: * Investigating the South African status quo with regard to housing policies and legislature. * Identifying the merits of historical theoretical models and their value in modern day housing development. * Discussing the importance of a locally focussed development approach with regard to the role of local municipalities versus provincial authorities in low-cost residential development. * Identifying the value of low-cost housing in local economic development and sustainable socio-economic growth. * Discussing the role of community participation in delivering sustainable neighbourhoods and communities. * Investigating the need for higher density development with specific reference to the integration of various housing typologies. * Exploring the relevance and benefits of alternative construction materials in low-cost residential development. * Exploring the informal backyard rental sector. * Exploring the approaches followed in South African case studies of varying successes in various provinces. It should be noted that the research conducted for this study, the conclusions drawn and the recommendations made provide substantial value, but are all mainly provided as preliminary concepts to be elaborated in a future PhD study. / Thesis (MArt et Scien (Urban and Regional Planning))--North-West University, Potchefstroom Campus, 2013