Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: See PDF for abstract. / AFRIKAANSE OPSOMMING: Sien die PDF vir die opsomming.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The demand for rail travel has increased over the years. As a result, it is becoming mandatory for railway industries to maintain very high availability of their assets to ensure that service levels are high. Railway industries require both their infrastructure and rolling stock assets maintained efficiently to sustain reliability. There has been on-going research on how maintenance can be carried out in a cost effective manner. However, the majority of this research has been done for infrastructure and the rolling stock maintenance has not been properly covered. The purpose of this research is to contribute to the maintenance sector of rolling stock for railway industries by developing a decision support model for rolling stock based on reliability and cost. The model is developed as an optimization problem of a system containing several components dependent on each other with different reliability characteristics. In this model, a mixed integer nonlinear problem is developed and solved using an exact method and metaheuristics methods. The Metrorail facility in Cape Town was chosen as a case study. Failure history and cost data were gathered from the facility and the information was applied to the model developed. The case study was investigated and different results were achieved using both exact and metaheuristics methods. The final result from the study is an optimal maintenance schedule based on reliability and cost. The developed model serves as a practical tool railway companies can adopt to schedule rolling stock maintenance to achieve a high level of reliability and at the same time maintaining minimum cost expenditure. / AFRIKAANSE OPSOMMING: Die vraag na spoorvervoer het oor die jare toegeneem. Dus het dit belangrik geword dat die spoorweg se bates hoogs toeganklik moet wees om te verseker dat die vlak van dienslewering hoog bly. Die spoorweg industrie besef dat hulle infrastruktuur, lokomotiewe, waens ens. effektief in stand gehou moet word sodat dit betroubaar kan wees. Navorsing word nog steeds gedoen oor hoe instandhouding op ’n koste-effektiewe wyse gedoen kan word. Die meeste van hierdie navorsing gaan egter oor infrastruktuur en instandhouding word nie ordentlik gedek nie. Die doel met hierdie navorsing is om by te dra tot die instandhoudingsektor van die spoorweg deur om ’n besluit-ondersteunende model vir lokomotiewe, waens, ens wat op betroubaarheid en koste gegrond is, te ontwikkel. Die model is ontwikkel as ’n optimasie probleem van ’n sisteem wat verskillende komponente wat van mekaar afhanklik is maar oor verskillende betroubaarheidskenmerke beskik, inluit. In hierdie model word ’n gemengde, heeltal nie-lineêre probleem ontwikkel en met ’n eksakte metode en metaheuristiese metodes opgelos. Die Metrorail fasiliteit in Kaapstad is vir die gevalle studie gekies. Die geskiedenis van mislukkings en koste data is by die fasiliteit versamel en die inligting is op die model wat ontwikkel is, toegepas. Die gevalle studie is ondersoek, en verskillende resultate is met eksakte en metaheuristiese metodes bereik. Die finale uitkomste van die studie is ’n optimale instandhoudingskedule wat op betroubaarheid en koste gegrond is. Die model wat ontwikkel is dien as ’n praktiese instrument wat spoormaatskappye kan gebruik om die instandhouding van lokomotiewe, waens ens. te reël sodat ’n hoë vlak van betroubaarheid bereik kan word en kostes terselfdertyd tot ’n minimum beperk kan word.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Statistics from mining accidents expose that the potential for injury or death to employees from occupational accidents is relatively high. This study attempts to contribute to the on-going efforts to improve occupational safety in the mining industry by creating a model capable of predicting the continuous risk of occupational accidents occurring. Model inputs include the time of day, time into shift, temperatures, humidity, rainfall and production rate. The approach includes using an Artificial Neural Network (ANN) to identify patterns between the input attributes and to predict the continuous risk of accidents occurring. As a predecessor to the development of the model, a comprehensive literature study was conducted. The objectives of the study were to understand occupational safety, explore various forecasting techniques and identify contributing factors that influence the occurrence of accidents and in so doing recognise any gaps in the current knowledge. Another objective was to quantify the contributing factors identified, as well as detect the sensitivity amongst these factors and in so doing deliver a groundwork for the present model. After the literature was studied, the model design and construction was performed as well as the model training and validation. The training and validation took the form of a case study with data from a platinum mine near Rustenburg in South Africa. The data was split into three sections, namely, underground, engineering and other. Then the model was trained and validated separately for the three sections on a yearly basis. This resulted in meaningful correlation between the predicted continuous risk and actual accidents as well as the majority of the actual accidents only occurring while the continuous risk was estimated to be above 80%. However, the underground section has so many accidents, that the risk is permanently very high. Yet, the engineering and other sections produced results useful for managerial decisions. / AFRIKAANSE OPSOMMING: Mynbou ongeluk statistieke dui aan dat die potensiaal vir besering of dood as gevolg van beroepsongelukke relatief hoog is. Die studie poog om by te dra tot die voortdurende verbetering van beroepsveiligheid in die mynbedryf deur middel van ’n model wat die risiko van beroepsongelukke voorspel. Die model vereis die tyd, tyd verstreke in die skof, temperatuur, humiditeit, reënval en produksie tydens die ongeluk as inset. Die benadering tot hierdie model maak gebruik van ’n Kunsmatige Neurale Netwerk (KNN) om patrone tussen die insette te erken en om die risiko van ’n voorval te beraam. As ’n voorloper tot die model ontwikkeling, is ’n omvattende literatuurstudie onderneem. Die doelwitte van die literatuur studie was om beroepsveiligheid beter te verstaan, verskeie voorspellings tegnieke te ondersoek en kennis van bydraende faktore wat lei tot voorvalle te ondersoek. Nog ’n doelwit sluit die kwantifisering in van geidentifiseerde bydraende faktore, asook die opsporing van die sensitiwiteit tussen hierdie faktore en hierdeur ’n fondasie vir die voorgestelde model te skep. Na afloop van die literatuurstudie is die model ontwikkel, opgelei en gevalideer. Die opleiding en validasie is deur middel van ’n gevallestudie in ’n platinummyn naby Rustenburg in Suid Afrika gedoen. Die data is verdeel in drie afdelings, d.i. ondergronds, ingenieurswese en ander. Die model is vir elke afdeling apart opgelei en gevalideer op ’n jaarlikse basis. Hierdie het gelei tot ’n betekenisvolle korrelasie tussen die voorspelde risiko en die werklike ongelukke met die meerderheid van die werklike ongevalle wat voorgekom het terwyl die risiko 80% oorskry het. In die ondergrondse afdeling is so baie voorvalle waarneem dat die risiko permanent hoog is. Die ander afdelings het wel resultate verskaf wat sinvol gebruik kan word in bestuursbesluite.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Effective management of spare parts inventory is essential to companies because it influences inventory costs and asset utilization. The vast and diverse portfolio of spare parts, intermittent demand patterns and contradicting objectives between departments are examples of some of the factors that complicate Spare Parts Management (SPM). Managers of spare parts are faced with trade-off decisions between risk and cost on a daily basis. These decisions include, amongst many, determining appropriate stock levels and order frequencies. Despite the importance of SPM, decisions are however often made intuitively in practice with little factual support, and the decision-making process is commonly constrained within departmental silos. Even though there is a large body of academic knowledge on this topic, practical applications of spare parts inventory solutions lag behind theoretical studies. The majority of studies in literature focus on single components of SPM, such as demand forecasting and parts classification, whereas fewer studies consider the decision-making process itself. This study proposes a decision-making framework for spare parts inventory management. The framework is based on a wide-ranging literature review that focuses on capturing the essence of Spare Parts Management (SPM), but also acknowledges the interconnectedness of the problem. Therefore, core inventory management principles, as well as closely related topics such as Supply Chain Management (SCM) and Physical Asset Management (PAM), are studied in the context of spare parts. The broad scope of the literature study leads to a holistic approach to the problem and prevents sub-optimization. The proposed framework condenses principles from various fields of study (SCM, PAM, Classification and Inventory Management) into a stepwise methodology presented as a decision-making framework. The objective of the framework is to provide managers with a structured process, based on factual information, to enable better decision-making in the field. Furthermore, the framework aims to capture the fundamentals of SPM in a simplistic manner to ease the adoption of the framework in practice. A case study is conducted in the South African mining industry to validate the framework. The case study demonstrates that the framework is practical, provides structured guidance, and assists managers to make trade-off decisions in managing spare parts inventory. / AFRIKAANSE OPSOMMING: Effektiewe voorraadbestuur van onderdele is belangrik vir maatskappye omdat dit voorraadkoste en die benutting van bates beïnvloed. Die bestuur van onderdele is ’n komplekse probleem. Ondermeer is die portefeulje van onderdele items breed en divers, die vraagpatrone sporadies en word die voorraadvlakke geaffekteer deur kontrasterende doelwitte tussen verskillende departemente. Bestuurders van onderdele word daagliks gekonfronteer met besluite rakende risiko’s en kostes, soos om toepaslike voorraadvlakke te bepaal en om te besluit wanneer om bestellings te plaas. Hierdie besluite word dikwels intuïtief geneem met min feitelike ondersteuning en insette in die besluitnemingsproses word gereeld beperk tot sekere departemente. Ten spyte van die geweldige akademiese belang in die onderwerp, is daar min suksesvolle praktiese toepassings. Die meerderheid van studies in die literatuur fokus op spesifieke elemente van onderdele bestuur, soos vooruitskatting en klassifisering van parte, terwyl minder op die besluitnemingsproses konsentreer. Hierdie studie stel ’n besluitnemingsraamwerk vir die bestuur van onderdele voorraad voor. Die raamwerk is gegrond op ’n deeglike literatuurstudie wat die essensie van onderdele bestuur ondersoek, maar ook die interverbondenheid van die probleem in ag neem. Voorraadbestuurbeginsels en verwante onderwerpe soos Voorsieningskettingbestuur en Fisiese Batebestuur word dus bespreek. Die breë omvang van die literatuurstudie lei tot ’n holistiese benadering wat sub-optimering van die probleem voorkom. Die voorgestelde raamwerk som beginsels uit verskillende relevante studievelde op in ’n stapsgewyse metode wat voorgestel word as ’n besluitnemingsraamwerk. Die doel van die raamwerk is om bestuurders te voorsien met ’n gestruktureerde proses, gebaseer op feitelike inligting, om besluitneming in die veld te verbeter. Verder poog die raamwerk om die fundamentele konsepte in voorraadbestuur vas te vang in ’n eenvoudige manier sodat die raamwerk maklik geïmplementeer kan word in die praktyk. Die voorgestelde raamwerk is gevalideer deur middel van ’n gevallestudie in die Suid-Afrikaanse mynbedryf. Die gevallestudie toon dat die voorgestelde raamwerk prakties is, die besluitnemingsproses op ’n gestruktureerde wyse lei, en bestuurders help om beter, ingeligte besluite te neem.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: There is a strong focus on the use of titanium and its alloys in the aerospace industry due to the high ultimate tensile strength and high strength-to-weight ratio of the material. The high performance nature of the material also makes it difficult and costly to machine. South Africa has the second most abundant titanium resources in the world in the form of rutile and ilmenite but no value chain to produce titanium parts from the ore. Currently, the ore is sold overseas at low prices. There exists an initiative to create a full titanium value chain in South Africa by the Department of Science and Technology. This project forms part of this initiative, where local industry is equipped with knowledge and skills to produce and machine titanium parts. The focus of this study is to determine whether it is possible to machine titanium aerospace parts at a local industry partner and equip the industry partner with knowledge and skills in order to facilitate effective and economical machining of these parts. Daliff Precision Engineering was selected as the local industry partner and specific demonstrator parts were selected on which to base the study. The process the industry partner currently uses to machine aerospace parts from difficult-to-machine alloys was studied and evaluated. It was found that about 70% of the machining time was spent on a single roughing process, hence the decision to study the roughing process in an attempt to establish whether improvement was possible. Pilot tests were done at the facilities of the industry partner and time savings of 95% were realised on the roughing process. A 2-level 3-factor Design of Experiments methodology was followed for experimentation and analysis of titanium machining at the industry partner. The roughing process of the demonstrator part was simulated on the CNC machining centre and the depth of cut, cutting speed and feed per tooth were selected as the factors, and the response was tool wear. A statistical analysis was done using Modde 9.1 design of experiments software and an optimisation model was created in order to determine a feasible set of cutting parameters, maximise material removal rate and have a target amount of tool wear. The findings show that it is possible to economically machine titanium aerospace parts with a selected geometry at the industry partner without the need for significant capital investments. The industry partner can use the knowledge generated in this project to validate their titanium machining capabilities and form part of the titanium value chain that is being developed in South Africa. / AFRIKAANSE OPSOMMING: Daar is ‘n groot fokus op die gebruik van titaan allooie in die lugvaart nywerheid, as gevolg van die material se hoë trek-sterkte en hoë sterkte-tot-gewig verhouding. Die eienskappe wat die material so aantreklik maak, is ook die rede wat dit moeilik en duur maak om te masjineer. Suid-Afrika het die tweede grootste titaan reserwes in die wêreld in die vorm van rutiel en ilmeniet erts, maar geen waarde ketting om titaan onderdele te vervaardig van die erts af nie. Die erts word tans oorsee verkoop teen lae pryse. Daar is tans ‘n inisiatief om ‘n titaan waardeketting in Suid-Afrika te skep deur die Departement van Wetenskap en Tegnologie. Hierdie projek vorm deel van hierdie inisiatief om die plaaslike nywerheid toe te rus met kennis en vaardighede om titaan produkte te vervaardig. The fokus van hierdie studie is om te bepaal of dit moontlik is om titaan lugvaart onderdele te masjineer by ‘n plaaslike industrie-vennoot en om hierdie vennoot met kennis en vaardighede toe te rus om hierdie onderdele effektief en ekonomies te vervaardig. Daliff Precision Engineering is gekies as die plaaslike industrie-vennoot en spesifieke demonstrator onderdele is gekies om die studie op te baseer. Die proses wat die industrie-vennoot tans gebruik om moeilik-om-te-masjineer allooie te masjineer is bestudeer en ge-evalueer. Daar was bevind dat 70% van die masjineringstyd bestee word aan ‘n enkele uitrof-proses. Daar is besluit om vas te stel of die uitrof-proses verbeter kan word. Loods-eksperimente is gedoen by die industrie-vennoot se fasiliteite en ‘n tydsbesparing van 95% is gevind op die uitrof-proses. ‘n 2-Vlak 3-faktor eksperimentele ontwerp metodologie is gevolg om eksperimente by die industrie-vennoot op titaan uit te voer en te analiseer. Die uitrof-proses van die demonstrator onderdeel is gesimuleer op die CNC masjineringsentrum en die diepte van snit, snyspoed en voer per tand is gekies as die faktore en beitel-slytasie is gekies as die respons. ‘n Statistiese analise is gedoen deur Modde 9.1 eksperimentele ontwerp sagteware te gebruik om ‘n moontlike stel van sny-parameters te identifiseer om die materiaal-verwyderingstempo te maksimeer en die teiken waarde vir beitel-slytasie te bereik. Daar is gevind dat dit moontlik is on titaan lugvaart onderdele met ‘n spesifieke geometrie ekonomies te masjineer by die industrie-vennoot, sonder om enige beduidende kapitaal uitgawes aan te gaan. Die industrie-vennoot kan die kennis gebruik wat geskep is deur die projek om hulle titaan masjineringsvaardighede te valideer en om deel te vorm van die titaan waardeketting wat besig is om in Suid-Afrika ontwikkel te word.

Thesis (MEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: South Africa’s health sector has not yet shown enough improvement to reach the Millennium Development Goals related to health. One of the problem areas is the low infant and child vaccination coverage in certain areas of South Africa. The use of mobile phones in health care (mHealth) has the potential to strengthen the primary health care system through improved information management. A mobile health solution for vaccination (MHSV) can be used to improve information management of vaccinations, which in turn can improve vaccination coverage. However, the feasibility of implementing such an MHSV in the South African context is unknown. This study therefore investigates the feasibility of using mobile phones to improve information management for child vaccinations in South Africa. Feasibility is determined by using a feasibility framework together with business model development. The feasibility framework, which is informed by a literature study, surveys and a case study, determines the feasibility of an MHSV in terms of human factors, technical feasibility, information management, policies and ethics, and economics. It is found that an MHSV is feasible in South Africa, although certain areas pose challenges that will have to be considered. Complementing the feasibility framework, business models are developed to suggest possible ways in which an MHSV can be deployed in South Africa. These models build on the results from the feasibility framework and are developed using Osterwalder’s business model canvas. The effect of the National Health Insurance (NHI) on these business models is also examined. In order to validate the feasibility framework and business models, interviews were held with experts in health care and mobile phone solutions. These interviews show that the research is valid and that the feasibility framework and business models can be generalised to the wider field of mHealth solutions. / AFRIKAANSE OPSOMMING: Suid-Afrika se gesondheidsektor het nog nie genoeg verbetering getoon om die gesondheidsverwante Millenium Ontwikkelingsdoelwitte te bereik nie. Een van die probleemareas is die besondere lae inentingsdekking van babas en kinders in sekere gebiede van Suid-Afrika. Die gebruik van selfone vir gesondheidsorg hou die potensiaal in om die primêre gesondheidsorgstelsel te versterk deur inligtingsbestuur te verbeter. ’n Inentingsoplossing wat gebruik maak van selfone, bekend as ‘n “mobile health solution for vaccination” (MHSV), kan inligtingsbestuur van inentings verbeter, wat hoër inentingsdekking tot gevolg kan hê. Die haalbaarheid van die implementering van so ’n MHSV in die konteks van Suid-Afrika is egter onbekend. Hierdie studie ondersoek dus die haalbaarheid daarvan om selfone te gebruik vir beter inligtingsbestuur van kinder-inenting in Suid-Afrika. Haalbaarheid word vasgestel deur ’n haalbaarheidsraamwerk en die ontwikkeling van besigheidsmodelle te gebruik. Die haalbaarheidsraamwerk, wat toegelig word deur ’n literatuurstudie, vraelyste en ’n gevallestudie, bepaal die haalbaarheid van ’n MHSV in terme van menslike faktore, tegniese haalbaarheid, inligtingbestuur, beleid en etiek, en ekonomie. Daar word gevind dat ’n MHSV haalbaar is in Suid-Afrika, alhoewel sekere areas uitdagings inhou. Die haalbaarheidsraamwerk word aangevul deur die ontwikkeling van besigheidsmodelle wat moontlike maniere voorstel waarop ’n MHSV in Suid-Afrika ontplooi kan word. Hierdie modelle word geskoei op die resultate van die haalbaarheidsraamwerk en word ontwikkel met behulp van Osterwalder se besigheidsmodelskema (“business model canvas”). Die effek van die nasionale gesondheidversekering op hierdie modelle word ook ondersoek. Onderhoude met kundiges in die veld van selfoonoplossings vir gesondheidsorg word gebruik om die haalbaarheidsraamwerk en die besigheidsmodelle te valideer. Die onderhoude toon dat die navorsing geldig is en dat die haalbaarheidsraamwerk en besigheidsmodelle veralgemeen kan word na die wyer veld van selfoonoplossings vir gesondheidsorg.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: South Africa's system of socio-economic development planning is complex and ine ective. There are many regulatory authorities involved, often with unclear responsibilities and inadequate procedures of implementing objectives. Planning for development in South Africa needs to take various factors into account. Economic growth is pursued, while social imbalances are addressed and the environment is protected against unreasonable damage. The term Sustainable Development is an important concept in the vision of many of the regulating authorities, however, the implementation of sustainability is di cult. This study considers an approach which aligns activities in a specifi ed region to the vision and objectives of the applicable regulatory authorities, as an alternative to achieving objectives strictly through enforcing regulations. This thesis developed an integrated evaluation model which can be used to evaluate the alignment of a small-scale farm to the visions and objectives of certain regulatory authorities. Four small-scale farms in the Letaba catchment of the Limpopo Province were used as a case study to be evaluated against national and regional development visions. On a national level the National Development Plan (NDP), the National Framework for Sustainable Development (NFSD), the Integrated Sustainable Rural Development Strategy (ISRDS) and the principles of Water Allocation Reform (WAR) were regarded. For regional categorisation, the relevant municipal Integrated Development Plan (IDP), Spatial Development Framework (SDF), Local Economic Development (LED) plan and the applicable Catchment Management Strategy (CMS) were considered. The Letaba catchment area has speci c development constraints regarding water. For this reason, the impact the four farms have on the water of the region was evaluated in addition to their alignment with regional development visions. The hydrological evaluations were performed through the use of the Soil and Water Assessment Tool. Hereby it was determined whether objectives of development planning were realistic in terms of water availability. It was established that the location of a farm is a determining factor of the impact it has on the catchment area's water supply. The developed Integrated Evaluation Model combined all the visions and objectives of the mentioned strategic documents to speci cally assess the contribution a small-scale farm makes. The evaluation results provide insight into the alignment of activities to the ideals of a region and can be useful when formulating actions to reach a common vision. Small-scale farms are well-aligned to the objectives of WAR, the CMS and ISRDS. The farms have a limited contribution to the ideals of the NDP and NFSD and results against the IDP, the SDF and the LED di er considerably for each farm. Furthermore, the results of the farms' alignment with regional objectives do not correspond to the hydrologically ideal locations. Therefore, the development of small-scale farming should take hydrological information into consideration. The Integrated Evaluation Model proves to be valuable, understandable and applicable to evaluate the alignment of small-scale farms to the visions of regulatory authorities. / AFRIKAANSE OPSOMMING: Suid-Afrika se sisteem van beplanning vir sosio-ekonomiese ontwikkeling is ingewikkeld en one ektief. Daar is verskillende regulatoriese owerhede betrokke wat maklik aanleiding gee tot onsekerheid ten opsigte van verantwoordelikhede asook tot onvoldoende benaderings tot implementering. Om ontwikkeling in Suid-Afrika suksesvol te laat geskied, moet verskeie faktore inaggeneem word. Behalwe vir die strewe na ekonomiese groei, moet sosiale agterstande gelyktydig aangespreek word en moet hierdie ontwikkeling van so 'n aard wees dat die omgewing nie onnodige skade lei nie. Volhoubaarheid is 'n gemeenskaplike ideaal van die meeste partye betrokke by die beplanning van Suid-Afrika se ontwikkeling. Die implementering van hierdie oogmerk is egter onduidelik. Hierdie studie oorweeg 'n benadering wat alle handelinge in 'n bepaalde gebied in ooreenstemming bring met die visie en doelwitte van die toepaslike regulatoriese owerhede. Hierdie benadering word as 'n alternatief gestel teenoor 'n benadering om doelwitte slegs deur regulasies te bereik. Hierdie tesis het 'n Geïntegreerde Evalueringsmodel ontwikkel wat die mate waartoe 'n klein plaas 'n bydrae maak tot die visie en doelwitte van regulatoriese owerhede meet. Vier kleinskaalse boerderye in die Letaba Opvangsgebied in Limpopo was ondersoek as 'n gevallestudie. Hierdie plase is geëvalueer teen nasionale- en streeksontwikkelingsvisies. Op 'n nasionale vlak is die Nasionale Ontwikkelings Plan (NOP), die Nasionale Raamwerk vir Volhoubare Ontwikkeling (NRVO), die Geïntegreerde Volhoubare Landelike Ontwikkelings Strategie (GVLOS) en die waardes van die Water Toekenning Hervorming (WTH) beskou. Ten opsigte van streeksontwikkeling, is die betrokke munisipale Geïntegreerde Ontwikkelings Plan (GOP), die Ruimtelike Ontwikkelings Raamwerk (ROR), Plaaslike Ekonomiese Ontwikkeling (PEO) plan en die gepaste Opvangsgebied Bestuurs Plan (OBP) inaggeneem. Water is 'n beperkende faktor tot ontwikkeling in die Letaba opvangsgebied. Omrede, word die vier plase se impak op die watertoestand van die gebied bepaal, sowel as die bydrae tot die visie van die regulatoriese owerhede. 'n Opstelling van die studie-area is gemaak met die Soil and Water Assessment Tool ten einde hidrologiese a eidings te maak. Hierdeur is bepaal of die visies en doelwitte soos gestel deur die beplanningsdokumente vir ontwikkeling, realisties is ten opsigte van die waterbeskikbaarheid. Die studie het bevestig dat die ligging van 'n plaas 'n bepalende faktor is tot die plaas se uitwerking op die gebied se water. Die ontwikkelde Geïntegreerde Evalueringsmodel kombineer die visies en doelwitte van die bogenoemde strategiese dokumente om die bydrae van 'n klein plaas te meet. Die evalueringsresultate verskaf insigte rondom die ooreenstemming van plase teenoor die visie van 'n streek en kan nuttig gepas kom wanneer spesi eke aksies beplan word om 'n gemeenskaplike doelwit te bereik. Kleinskaalse boerdery is in lyn met die doelwitte soos bepaal deur die OBP, GVLOS en WTH. Die bydrae wat die plase ten opsigte van die NOP en NRVO se ideale maak is egter beperk. Verder verskil die resultate grootliks vir elke plaas ten opsigte van die bydrae gelewer tot die visies van die GOP, ROR en PEO. Gewensde resultate ten opsigte van bydrae tot ontwikkelingsvisies het nie ooreengestem met die liggings wat aanbeveel is deur die hidrologiese studie nie. Dus moet hidrologiese inligting inaggeneem word tydens besluitneming vir die ontwikkeling van kleinskaalse boerdery. Die Geïntegreerde Evalueringsmodel bied waarde, is toeganklik en is toepaslik om kleinskaalse boerdery te meet tenoor die visies van regulatoriese owerhede.

Thesis (MScEng) Stellenbosch University, 2014 / ENGLISH ABSTRACT: This thesis brings together productivity and risk assessments through innovative design, development and evaluation of a unique system for retrieving and analysing data. In the past, although the link between them is well-documented, these assessments have largely been dealt with as separate antagonist entities. A broad evaluation of the existing traditional and technological support systems has been conducted to identify suitable methodologies along with a common technological platform for automation. The methodologies selected for the productivity and risk assessments were; work sampling and the revised NIOSH lifting equation respectively. The automation of these procedures is facilitated through computer vision and the use of a range imaging Kinect™ camera. The standalone C++ application integrates two tracking approaches to extract real-time positional data on the worker and the work-piece. The OpenNI and OpenCV libraries are used to perform skeletal tracking and image recognition respectively. The skeletal tracker returns positional data on specific joints of the worker, while the image recognition component, a SURF implementation, is used to identify and track a specific work-piece within the capture frame. These tracking techniques are computationally expensive. In order to enable real time execution of the program, Nvidia’s CUDA toolkit and threading building blocks have been applied to reduce the processing time. The performance measurement system is a continuous sampling derivative of work sampling. The speed of the worker’s hand movements and proximity to the work-piece are used to classify the worker in one of four possible states; busy, static, idle, or out of frame. In addition to the worker based performance measures, data relating to work-pieces are also calculated. These include the number of work-pieces processed by a specific worker, along with the average and variations in the processing times. The risk assessment is an automated approach of the revised NIOSH lifting equation. The system calculates when a worker makes and/or breaks contact with the work-piece and uses the joint locations from the skeletal tracker to calculate the variables used in the determination of the multipliers and ultimately the recommended weight limit and lifting index. The final calculation indicates whether the worker is at risk of developing a musculoskeletal disorder. Additionally the information provided on each of the multipliers highlights which elements of the lifting task contribute the most to the risk. The user-interface design ensures that the system is easy to use. The interface also displays the results of the study enabling analysts to assess worker performance at any time in real time. The automated system therefore enables analysts to respond rapidly to rectify problems. The system also reduces the complexity of performing studies and it eliminates human errors. The time and costs required to perform the studies are reduced and the system can become a permanent fixture on factory floors. The development of the automated system opens the door for further development of the system to ultimately enable more detailed assessments of productivity and risk. / AFRIKAANSE OPSOMMING: Produktiwiteit en risiko evaluerings word in hierdie tesis saam hanteer deur die innoverende ontwerp, ontwikkeling en evaluering van 'n unieke stelsel vir die meting en ontleding van data. Alhoewel die skakel tussen hulle goed gedokumenteer is, word hierdie evaluering as afsonderlike antagonistiese entiteite hanteer. 'n Breë studie van die bestaande tradisionele en tegnologiese ondersteuningstelsels is gedoen om toepaslike metodes te identifiseer, om 'n gemeenskaplike tegnologiese platform vir outomatisering daar te stel. Die metodes wat gekies is vir die produktiwiteit en risiko bepalings is onderskeidelik werk monsterneming en die hersiende NIOSH opheffing vergelyking. Die outomatisering van hierdie prosedures word gefasiliteer deur middel van rekenaar visie en die gebruik van 'n Kinect™ 3D kamera. Die selfstandige C++ program integreer ‘n dubbelvolgings benadering om in reële tyd posisionele data van die werker en die werk-stuk te kry. Die OpenNI en OpenCV biblioteke word onderskeidelik gebruik om skeletale volging en beeld erkenning uit te voer. Die skeletale volger bepaal posisionele data van spesifieke gewrigte van die werker, terwyl die beeld erkenning komponent, 'n SURF implementering gebruik om 'n spesifieke werk-stuk binne die opname raam te identifiseer en te volg. Hierdie volgings tegnieke is berekenings intensief. Om werklike tyd uitvoering van die program te verseker, is Nvidia se CUDA gereedskapstel en liggewig boublokke geimplementeer. Die produktiwiteit meting-stelsel is 'n aaneenlopende monsterneming benadering van werk monsterneming. Die spoed van die werker se handbewegings en nabyheid aan die werkstuk word gebruik om die werker te klassifiseer as in een van vier moontlike toestande; besig, staties, onaktief of buite die raam. Benewens die werker gebaseerde metings, word daar ook data oor werkstukke bereken. Dit sluit in die aantal werkstukke verwerk deur 'n spesifieke werker, sowel as die gemiddelde en variasie in verwerkings tye. Die risiko-berekening is 'n outomatiese benadering van die hersiende NIOSH opheffing vergelyking. Die stelsel bereken wanneer die werker kontak maak en/of breek met die werkstuk en maak gebruik van die gewrigsposisies wat die skeletale volger aandui om die veranderlikes wat in die vermenigvuldigers gebruik word te bepaal. Die vermenigvuldigers word gebruik om die aanbevole maksimum gewig en die opheffing indeks te bereken. Die opheffing indeks dui aan of daar ‘n risiko vir die werker is om muskuloskeletale versteuring te ontwikkel. Benewens dui die vermenigvuldigers aan watter elemente die grootste bydra tot die risiko van die opheffingstaak maak. Die gebruiker-koppelvlak-ontwerp verseker dat die stelsel maklik is om te gebruik. Die koppelvlak vertoon ook die resultate van die studie sodat ontleders op enige tyd werker prestasie kan evalueer in reële tyd. Die outomatiese stelsel stel dus ontleders in staat om vinnig te reageer sodat probleme reggestel kan word. Die stelsel verminder ook die kompleksiteit vir die uitvoering van studies en dit elimineer menslike foute. Die tyd en koste vereis om die studie te doen, word verminder en die stelsel kan ‘n permanente instelling op fabriekvloere geword. Die ontwikkeling van die outomatiese stelsel maak die deur oop vir verdere ontwikkeling van die stelsel om uiteindelik daartoe te lei dat meer gedetailleerde evaluering van produktiwiteit en risiko bepaal kan word.