Doctoral Degrees (Industrial Engineering)

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Adaptive games for learner and systems (bidirectional) learning
(Stellenbosch : Stellenbosch University, 2022-04) von Leipzig, Tanja; Schutte, Cornelius Stephanus Lodewyk ; Lutters, Eric; Hummel, Vera; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT:Traditional learning environments are ineffective and inefficient and are failing to adequately equip students and employees with the knowledge and skills required in today’s jobs, let alone prepare them for the jobs of tomorrow. Given the rapidly changing landscapes of technologies and business models, organisations need to be flexible and adaptable to respond to, and even pre-empt future demands. One of the primary shortcomings of existing learning environments is their inflexibility and the ‘one size fits all’ approach followed. Serious games and game-based learning are widely recognised for their potential in providing more effective learning environments, especially when designed in a personalised, adaptive manner, and are explored in this dissertation. In addition to adapting to the individual traits and preferences of users, games are also highly context dependent. Whilst there is a great deal of literature and documented case studies of game-based learning, most focus only on the implementation of one particular game in a specific context. Whilst many existing game design models and approaches focus on achieving improved learning outcomes of learners, there is an opportunity to consider the impact of gameplay on other stakeholders and drive the active development of meta-skills in various stakeholders. Bidirectional learning, where learning simultaneously takes place in a two-way direction [295], has great potential and has, to date, not been incorporated in serious game design. By integrating different perspectives and variable scenarios, the dynamic personalisation of learning trajectories may be possible. Serious games offer a potential platform to aggregate learner behaviours and results, and use these to dynamically configure, adjust and tailor the game to individuals and contexts, ultimately providing a learning environment of improved quality, effectiveness and efficiency. In this dissertation, adaptive, bidirectional games are explored as a means to provide more effective and efficient learning environments for multiple stakeholders. Moreover, an architecture is presented to support the creation of such games for specific scenarios in a faster, more effective and more efficient manner. Following a research-by-design approach, the architecture is iteratively developed and simultaneously applied in four case studies. Experiences and learnings from each case study are infused into subsequent design iterations of the architecture. The architecture allows users to explore and exploit the solution space more deliberately and better understand the various functions and the interrelations between them. The flexible and modular structure of the architecture allows users to prioritise functionalities as required in the given scenario. Furthermore, the directional relations between functions can be interpreted and prioritised as needed given the specific context and requirements. The architecture incorporates various stakeholders in the design process, leading to greater transparency and better understanding throughout the process. More importantly, it emphasises bidirectional learning whereby different stakeholders can learn from gameplay and the aggregated results and behaviours of players.
An agent-based model of Eldana Saccharina Walker
(Stellenbosch : Stellenbosch University, 2016-12) Van Vuuren, Brian John; Potgieter, Linke; Bekker, James; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: An agent-based simulation model is formulated in this dissertation in order to simulate the population dynamics of Eldana saccharina Walker infestation in sugarcane. The simulation model comprises four distinct building blocks, namely a graphical user interface, the implementation of the life cycle and associated influence of temperature on E. saccharina, the mating process of E. saccharina and the oviposition and dispersal of E. saccharina. These building blocks are based on existing literature pertaining to the biology and behaviour of the pest and, in cases where the relevant literature is insu cient or non-existent, expert opinion and careful assumption. In order to select areas from existing sugarcane farms on which to execute location-speci c experiments, functionality which allows Geographic Information Systems (GIS) data importation is included as a platform on which to run the simulation model. These data inform the model in respect of the shape and characteristics of the underlying sugarcane elds in which the simulated E. saccharina population interacts. The model interacts and operates within an AnyLogic simulation software environment and, in so doing, aims to emulate the behaviour of a population of E. saccharina moths in sugarcane. It is anticipated that the model implementation may serve as a basis for facilitating future design and testing of control measures in order to suppress the pest and its consequent detrimental e ect to sugarcane through infestation and feeding on interior stalk nutrients. Numerous working mathematical models of the pest exist in the literature, but, in all previous cases, intricate aspects of the stalk borer's biology have been aggregated on a population level and average population changes have been a ected at discrete time steps. The resulting analyses therefore yield conclusions that do not necessarily re ect the continuous, changing nature of E. saccharina on a localised level. Using agent-based modelling, however, the pest's behaviour may be modelled in more detail so as to facilitate more thorough investigation of potential control strategies and their expected e cacy on the pest at di erent points in its life cycle. The agent-based simulation model designed in this dissertation is subjected to a number of veri cation and validation techniques. Furthermore, a pilot sensitivity analysis is conducted to identify the most in uential parameters in the simulation model. These parameters are then considered further in a comprehensive parameter variation analysis in order to illustrate the exibility and diversity of the model in terms of the variety of scenarios pertaining to E. saccha- rina population behaviour that it can accommodate. In some cases, simpli ed implementations of control measures are also imposed on the pest within the model in order to further illustrate its implementation capabilities, as anticipated for future model development and use. In light of this exibility, the model is also presented as a computerised decision support and analysis tool, including the ability to upload and recreate a speci c user's own sugarcane farm shape le, as well as to alter a set of available parameters. This may aid in simulating speci c behaviour in a simulation run in accordance with what has typically been observed by the user, or of hypothetical scenarios which require investigation. In turn, as the model is further developed and detailed control measures are included as part of the simulation execution, it is believed that an appropriate response pertinent to the characteristics of the geographical area under consideration and the corresponding E. saccharina population present in this area may be predicted, allowing for control measure alteration and redesign so as to optimise the associated parameters or actions prior to in- eld implementation. In order to further re ne the model and improve its accuracy, as well as ensure agreement between the existing modelling approaches and actual biological processes in nature, the entire simulation model of E. saccharina is subjected to an expert panel discussion. The experts comprising the panel encompass some of the key researchers pertaining to E. saccharina and other moth behaviour and population dynamics, both in South Africa and internationally. The simulation model is updated or adjusted according to suggestions made and new information shared by the expert panel in an attempt to simulate the pest as accurately as possible in accordance with the body of knowledge currently available. Although several other approaches to modelling E. saccharina populations have been adopted in the past, no existing models implement such a low level of abstraction with respect to the biology of the pest. In addition, previous models are often case-speci c, investigating speci c control measures that are imposed on an aggregate level on a population of the pest. By actively simulating E. saccharina's biological decision-making processes, intricate aspects pertaining to one or a number of interacting control strategies, as well as the manner in which they alter the pest's biology or behaviour, may easily be incorporated using an agent-based simulation modelling approach. Adopting a low level of abstraction also requires extensive information pertaining to the pest and, as such, areas where little understanding still exists with respect to the behaviour of E. saccharina have been highlighted and, consequently, may be prioritised for future entomological research by experts in the eld. Finally, numerous options for future investigation into this problem, including model re nement, control measure design and testing and comparison to existing models, pose positive possibilities for the eventual establishment of a functional, integrated pest management programme for E. saccharina.
An air suspension cushion to reduce human exposure to vibration
(Stellenbosch : University of Stellenbosch, 2007-03) Van der Merwe, Andre Francois; Van Niekerk, J. L.; University of Stellenbosch. Faculty of Engineering. Dept. of Industrial Engineering.
Off-road working vehicles are subjected to high levels of vibration input on the rough terrain and irregular roads they work. The human operators are therefore exposed to high levels of whole body vibration (WBV) and at risk of developing health problems. A number of international standards address the matter of whole body vibration, and the European Union issued a directive which limits the exposure of workers in the EU to WBV. Unfortunately, to date there is no law in South Africa requiring compliance with any of these EU standards nor guidelines. There are vehicles which are not fitted with suspension and/or suspension seats. The three wheeled logger used in forestry is a highly manoeuvrable and effective bulk handler, but without any form of suspension and no space under the operator’s seat to install a suspension seat. However, a suspension cushion can be retrofitted to existing vehicles largely alleviating the problem. To isolate low frequency vibration large suspension travel is required which makes an air suspension cushion attractive, as it can fully collapse. Additionally, a Helmholtz resonator if added to the cushion in the form of a pipe and tank, provides anti-resonance at a specific frequency. The resonator can be tuned by adjusting the pipe’s length and diameter as well as the volume of the tank. Larger diameter pipes have less friction and give better reduction of the transmissibility curve at the anti-resonance frequency. The SEAT value is a single number used to compare suspension seats for a specific input vibration. It is calculated from the weighted input acceleration power spectral density curve and the suspension seat transmissibility curve. The former is obtained from the vehicle and is vehicle, path and speed dependent. The latter is the only variable that can be improved by using a better suspension seat/cushion. The input power spectral density often contains significant energy at frequencies where the human operator is most sensitive. The cushion resonator could be tuned to position the anti-resonance in the transmissibility curve at these frequencies. The resultant output vibration would thus be lower than the input vibration at that frequency. In this dissertation an analytical model describes the state variables in the cushion, pipe and tank. A Simulink model predicts the transmissibility curve with a solid mass as well as with a two degree of freedom seated human model. Initially the prototype was tested with a solid mass to compare the transmissibility curve produced by the simulation with the experimental results. It was required to evaluate the contribution of the resonator without the complexity of the human impedance. Subsequent tests were carried out with human subjects. Test results showed high inter subject similarity at the anti-resonance frequencies. Design guidelines are formulated that can be used by the suspension cushion designer to specify the pipe diameter and length and the volume of the tank to determine the optimal transmissibility. Input psd from ISO7096 class EM3 vehicles is used as an example during the design process. A prototype air suspension cushion was designed to reduce output vibration on the three wheeled logger. Laboratory tests with human subjects showed a significant improvement at the problematic frequencies through the tuning of the resonator. Using a Helmholtz resonator with the air suspension cushion the overall SEAT value improved by 25% compared with a 100mm foam cushion. However, the current tank and pipe need to be reduced in size for practical implementation to the vehicle. Future work would include finding an alternative mass to replace the air in the pipe. This should reduce the size of the tank and the pipe required. Additionally the simultaneous effect of multiple resonators at different frequencies should be investigated. This is required for vehicles having an input psd with significant energy at more than one frequency band.
Alignment of internal and external business & innovation domains
(Stellenbosch : Stellenbosch University, 2017-03) Katz, Bernard; Du Preez, Niek; Louw, Louis; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: The concept of strategic alignment, the “golden thread”, lies at the heart of this research. The idea that all available resources are simultaneously attracted by the magnetic pull of a company’s strategy, like a million small compass needles, is both extremely desirable and incredibly difficult for a company to achieve. This dissertation, however, takes the concept of strategic alignment and pulls it and twists it and eventually shapes it so that it may be applied to the highly uncertain and complex environment of the innovation domain. It has been well established, that in the world today, adaptability is a key competitive advantage. Innovation has long been seen as a differentiator in company competitiveness. However, researchers and companies continue to struggle with the dichotomy between the open, unstructured and creative nature of innovation and the need to maximise the opportunity for innovation success through structure. The structuring of innovation activities was, for a long time, a controversial issue with the idea that strategy kills innovation being a widely expressed concern. Today, the value of an Innovation Strategy, which governs the innovation activities in a company, is widely accepted. This dissertation aims to contribute to the ongoing quest for a structured approach to innovation without harming the essence of innovation, human ingenuity. In working towards achieving this aim the Strategic Alignment Model was recognised as a wellestablished, logical and elegant model to manage the alignment between the overall business domain and a support function domain. Through analysis of the strategic alignment and innovation management literature, the Strategic Alignment Model was adapted to represent the alignment between the business and innovation domains. The adapted model is called the innovation Strategic Alignment Model (iSAM). The iSAM is a unique framework which integrates concepts from the field innovation management such as innovation scope, innovation maturity, innovation governance and innovation models with a well-established strategic alignment approach. No other model in the identified literature provided this link between these two research fields. The structure and content of iSAM was validated with a panel of experts and their feedback is included in various sections of the dissertation. The implementation of the iSAM in a real company requires a structured implementation framework. Such a framework is presented in this dissertation and both the iSAM and the implementation framework are tested through a multi-year case study. A key consideration is that it was not the aim of the case study to generalise the results for other industries or company types, but rather to demonstrate how such a model may be used to understand the alignment between the innovation and business domains and whether or not the model can be practically applied in order to generate alignment recommendations for a real company. Feedback from senior managers in the focus company was that the iSAM made the innovation landscape clearer and that through iSAM a greater understanding of the components of an Innovation Strategy was gained. This dissertation concludes with the summary of findings from the expert validation exercise and the multi-year case study. There seemed to be a general consensus amongst the experts that the iSAM does provide a valuable framework for Innovation Strategy alignment and that the model comprehensively addresses a critical issue facing companies. The experts also highlighted several areas of improvement and future research. These include: catering for variations in the model based on company size, company type and industry and further empirical evidence for some of the defined relationships in the model. From the case study it was concluded that iSAM provides a simple, clear, common understanding of the components involved in Innovation Strategy and innovation alignment, the implementation framework provides practical guidance and applicable tools to assist in determining innovation alignment and in following a change pathway to achieve alignment and the final recommendations provide clear instructions on what a company needs to do in order to ensure alignment is achieved. The case study also reveals several interesting challenges. These include: ensuring the entire management team engages with the model and the implementation approach and ensuring the applicability of the model for a specific company. Finally,it is the hope of the author that this dissertation initiates another small twig, which over time and through the work of other researchers in the field, contributes to the growing knowledge in the innovation domain.
Analysis and modelling of the track quality index
(Stellenbosch : Stellenbosch University, 2021-12) Laubscher, Stefan; Jooste, Wyhan
ENGLISH ABSTRACT: Technological advancements have caused an increase in available data in var- ious industries. Large quantities of data are collected on a daily basis, which adds to the high volumes of data already available. The railway industry is no exception to this, with geometry measurements such as track quality index (TQI) of perway being an example of high volumes of generated data in the railway industry. Public transportation is an important aspect of an urban area's sustainability, which includes railway transport. Inevitably, the assets associated with public railways require sufficient management and maintenance for a railway system to operate efficiently. With the importance of reliable railway infrastructure being evident, an opportunity is identified to make use of the data available about the condition of perway that would contribute towards successful asset management and predictive maintenance strategies. This research investigates methods of analysing and modelling track geometry data that would assist maintenance decision-making to ultimately deliver more reliable railway infrastructure. To formalise the process, a framework is developed to support railway operators in their perway data analysis activities. The framework outputs aid railway operators in their maintenance decision-making and shift the operations toward the predictive maintenance side of the maintenance spectrum. The study is performed based on the problem identified, a review of the associated literature and the selected research design and methodology which guide the research process. Through the research approach, the TQI Data Analysis Framework (TQI-DAF) is developed. The framework consists of three stages: Stage 1 - data collection and preparation; Stage 2 - data analysis; and Stage 3 visualisation and interpretation. The stages of the framework aim to assist railway operators to manage railway track infrastructure in a manner that would promote the reliable operation of the railway system. A case study is performed as part of this research to illustrate the framework's implementation and con rm its feasibility. The paper concludes with a summary of the performed study, a discussion about the degree of success with which the research objectives are met, the contributions the research is expected to make to the industry, limitations that are identified, and recommendations for future work.
An ant colony optimisation approach to scheduling truck and drone delivery systems
(Stellenbosch : Stellenbosch University, 2022-04) Tsietsi John, Moremi.; Grobler, Jacomine.; Kaminsky, Philip.
ENGLISH SUMMARY: ‘Last mile’ logistic scheduling is a complex problem businesses are facing today. Competitive pressure has increased with technological growth. The speed of delivering parcels to customers can be an excellent source of competitive advantage, since businesses are facing the challenge of efficiently delivering parcels to customers on a daily basis. The use of delivery drones in conjunction with traditional delivery vehicles is a new highly promising research direction explored in this thesis. This dissertation proposes various truck and drone delivery system optimisation problems where a delivery drone is launched from a purpose-built truck, completes additional deliveries while the truck is en route between two customer locations, and intercepts the truck after completing the additional delivery. The dissertation describes the development of an ant colony optimisation algorithm used to solve the problem. More specifically, an ant colony system with k-means clustering was used in this research. Adaptive algorithm control parameters were also used to ensure an acceptable balance between exploration and exploitation throughout the search process. The algorithm was tested on drone scheduling benchmark problems, optimal solution and other population-based metaheuristics and compared against a truck only delivery system. It was shown that the truck and drone delivery system has a significant positive impact on delivery time performance.
Application of additive manufacturing for improved thermal management of hot sheet metal forming tools
(Stellenbosch : Stellenbosch University, 2020-03) Muvunzi, Rumbidzai; Matope, Stephen; Harms, T. M.; Dimitrov, D. M.; Stellenbosch University. Faculty of Industrial Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: In hot stamping, a blank or sheet of metal at high temperature (800-900 °C) is formed and cooled simultaneously by the tools. The rapid cooling of the blank causes transformation to a martensitic microstructure with high tensile strength (1 500 MPa) which enables the parts to acquire crash resistant properties. Accordingly, the process is used to produce vehicle components for improving safety of passengers. However, the hot stamping tools are exposed to high thermal load as they come into contact with the hot blanks. To aid in the cooling, the tools have a network of drilled channels in which a coolant circulates to extract heat. Due to machining restrictions, the straight drilled channels are unable to ensure consistent cooling of geometrically complex parts. If the tools are not evenly cooled, thermal stresses are induced and this compromises the tool service life and quality of parts (hardness properties). Moreover, the average cooling time in hot stamping occupies at least 30 % of the total cycle time. Thus, one of the major challenges in hot stamping research is to find ways of reducing the cycle time. The above mentioned challenges can be resolved through exploiting the design freedom offered by Additive Manufacturing technologies in the producing of tools with cooling channels which conform to the shape of tools. This has already been extensively investigated in the injection moulding and die casting tooling industry. However, there is limited information on the design and manufacturing parameters of hot stamping tools with conformal cooling channels. The aim of this research was to apply Additive Manufacturing as a tool for improving thermal management of hot stamping tools. The first objective was to identify the parameters required for an effective thermal management system of hot stamping tools. A method for identifying the structural conformal cooling system parameters was developed based on the technical limitation of the Selective Laser Melting process, principles of mechanics and heat transfer. The developed method was validated using finite element analysis simulation on a typical benchmark component. The second objective of the study was to develop a model for predicting minimum cycle time in hot stamping under ideal conditions. The model was developed using heat transfer principles and study of the stages in hot stamping. The model is a useful benchmark tool which is applicable in cycle time prediction. The third and fourth objectives were to design and manufacture a hot stamping tool with conformal cooling channels for a benchmark part. The fifth objective was to investigate the impact of the tool with conformal cooling channels on cycle time. In view of that, experiments were conducted to compare the performance of the optimised tool and the conventional one under typical industry like conditions. According to the results, the conformable tool shows the potential of reducing cooling time by 29%.
An application of the supply chain operations reference model for the service supply chain for standardised back office services
(Stellenbosch : Stellenbosch University, 2017-12) Weyers, Morne; Louw, Louis; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: It is common practice to apply manufacturing practices to services, with the intention of improving services through the practices of manufacturing. One of the manufacturing practices that has proven to be valuable in recent years is Supply Chain Management. In line with this, we have seen a growing body of research in the area of Service Supply Chain Management. The greatest problem in Service Supply Chain Management, as indicated by the literature, is the ambiguity and complexity of services as opposed to manufacturing - where the concept of physical goods is easily understood. It is in this context, that researchers have found that it is challenging to apply current models for supply chain management to services in their current form. The concept of services is a very broad term and this proves to be a challenge. There is a subset of services that is more suited to have manufacturing practices, like supply chain management, directly applied to it. The main objective of this study is to show that a supply chain reference model can be developed with little adaptation to a model developed within the manufacturing industry. This model would be suitable for services that are highly standardised and repeatable, and exhibit characteristics seen in the manufacturing industry. The approach to the model adaptation is by using semantics, removal of elements (that relate to manufacturing) and limited addition of elements that relate to services. The objective is to create a model that is focused on standardised back-office services. The adapted service SCOR model is then tested for its usefulness. To test the usefulness of the adapted service SCOR model, the model is applied to a case study, which consists of two facilitated walk-throughs of services followed by a questionnaire assessment. The questionnaire was directed at assessing the usefulness of the models, which would only be the case if the constructs of the model were practical to the professionals assessing the model. An adapted service SCOR model could be created for standardised back-office services by applying a structured approach to adapting the existing SCOR model. The adapted service SCOR model was found to be valid by professionals within standardised back-office services. There is a subset of services in which the supply chain management principles are more relevant and can be applied to services with a lesser modification. An approach to the adaptation of the SCOR model is provided. This approach maintains the integrity of the original SCOR model while making the SCOR model suitable to the specific type of services. This approach may be applied by practitioners adapting the SCOR model for their specific application but specifically for service sectors. In the application, the practitioner can then utilise the SCOR model concepts without having to create new concepts for services. Therefore, it is believed to be a unique contribution in classifying services into distinct categories when applying supply chain principles, from manufacturing to service supply chains. It may also be expanded to manufacturing practices in general.
Application of Van-der-Waals forces in micro-material handling
(Stellenbosch : Stellenbosch University, 2012-12) Matope, Stephen; Van der Merwe, A. F.; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
This doctoral dissertation focuses on the application of Van-der-Waals’ forces in micromaterial handling. A micro-material handling system consists of four main elements, which include: the micro-gripper, the micro-workpart, the picking up position and the placement position. The scientific theoretical frameworks of Van-der-Waals’ forces, presented by Van der Waals, Hamaker, London, Lifshitz, Israelachvilli, Parsegian, Rumpf and Rabinovich, are employed in exploring the extent to which these forces could be applied in a micromanufacturing situation. Engineering theoretical frameworks presented by Fearing, Bohringer, Sitti, Feddema, Arai and Fukuda, are employed in order to provide an in-depth synthesis of the application of Van-der-Waals’ forces in micro-material handling. An empirical or pragmatic methodology was adopted in the research. The Electron Beam Evaporation (e-beam) method was used in generating interactive surfaces of uniform surface roughness values. E-beam depositions of copper, aluminum and silver on silicon substrates were developed. The deposition rates were in the range of 0.6 – 1.2 Angstrom/s, at an average vacuum pressure of 2 x 10-6 mbar. The topographies were analysed and characterised using an Atomic Force Microscope and the corresponding rms surface roughness values were obtained. The Rumpf-Rabinovich equation, which gives the relationship of the exerted Van-der-Waals’ forces and the rms surface roughness values, is used to numerically model the results. In the final synthesis it is observed that the e-beam depositions of copper are generally suited for the pick-up position. Aluminum is suited for the micro-gripper and silver is suited for the placement position in an optimised micro-material handling system. Another Atomic Force Microscope was used in order to validate the numerically modelled results of the exerted Van- der-Waals’ forces. The aim was to measure the magnitude of Vander- Waals’ forces exerted by the e-beam depositions and to evaluate their applicability in micro-material handling operations. The measurements proved that Van-der-Waals’ forces exerted by the samples could be used for micro-material handling purposes on condition that they exceeded the weight of the micro-part being handled. Three fundamental parameters, ie: material type, geometrical configuration and surface topography were used to develop strategies of manipulation of micro-materials by Van-der- Waals’ forces. The first strategy was based on the material type variation of the interactive surfaces in a micro-material handling operation. This strategy hinged on the fact that materials have different Hamaker coefficients, which resulted in them experiencing a specific Van-der- Waals’ forces’ intensity during handling. The second strategy utilised variation in the geometrical configuration of the interacting surfaces. The guiding principle in this case was that, the larger the contact area was, the greater the exerted Van-der-Waals’ forces would be In the analytical modelling of Van-der-Waals’ forces with reference to geometrical configuration, a flat surface was found to exert more force than other configurations. The application of the design, for purposes of manufacturing and assembling (DFMA) criteria, also proved that flat interactive surfaces have high design efficiency. The third strategy was based on surface roughness. The rougher the topography of a given surface was, the lesser the Van-der-Waals’ forces exerted were. It was synthesised that in order for a pick-transfer-place cycle to be realised, the root-mean-square (rms) interactive surface roughness values of the micro-part (including the picking position, the micro-gripper, and the placement position) should decrease successively. Hybrid strategies were also identified in this research in order to deal with some complex cases. The hybrids combined at least two of the aforementioned strategies.
Applying the cross-entropy method in multi-objective optimisation of dynamic stochastic systems
(Stellenbosch : Stellenbosch University, 2012-12) Bekker, James; Van Vuuren, J. H.; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: A difficult subclass of engineering optimisation problems is the class of optimisation problems which are dynamic and stochastic. These problems are often of a non-closed form and thus studied by means of computer simulation. Simulation production runs of these problems can be time-consuming due to the computational burden implied by statistical inference principles. In multi-objective optimisation of engineering problems, large decision spaces and large objective spaces prevail, since two or more objectives are simultaneously optimised and many problems are also of a combinatorial nature. The computational burden associated with solving such problems is even larger than for most single-objective optimisation problems, and hence an e cient algorithm that searches the vast decision space is required. Many such algorithms are currently available, with researchers constantly improving these or developing more e cient algorithms. In this context, the term \e cient" means to provide near-optimised results with minimal evaluations of objective function values. Thus far research has often focused on solving speci c benchmark problems, or on adapting algorithms to solve speci c engineering problems. In this research, a multi-objective optimisation algorithm, based on the cross-entropy method for single-objective optimisation, is developed and assessed. The aim with this algorithm is to reduce the number of objective function evaluations, particularly when time-dependent (dynamic), stochastic processes, as found in Industrial Engineering, are studied. A brief overview of scholarly work in the eld of multiobjective optimisation is presented, followed by a theoretical discussion of the cross-entropy method. The new algorithm is developed, based on this information, and assessed considering continuous, deterministic problems, as well as discrete, stochastic problems. The latter include a classical single-commodity inventory problem, the well-known buffer allocation problem, and a newly designed, laboratory-sized recon gurable manufacturing system. Near multi-objective optimisation of two practical problems were also performed using the proposed algorithm. In the rst case, some design parameters of a polymer extrusion unit are estimated using the algorithm. The management of carbon monoxide gas utilisation at an ilmenite smelter is complex with many decision variables, and the application of the algorithm in that environment is presented as a second case. Quality indicator values are estimated for thirty-four test problem instances of multi-objective optimisation problems in order to quantify the quality performance of the algorithm, and it is also compared to a commercial algorithm. The algorithm is intended to interface with dynamic, stochastic simulation models of real-world problems. It is typically implemented in a programming language while the simulation model is developed in a dedicated, commercial software package. The proposed algorithm is simple to implement and proved to be efficient on test problems.
An approach to enable and advance open innovation for small and medium-sized enterprises
(Stellenbosch : Stellenbosch University, 2017-12) Krause, Willie; Schutte, C. S. L.; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: Small and medium-sized enterprises form a very important part of any economy. These organisations generally provide 60–70 percent of the employment in countries. The success and growth of SMEs have a direct impact on a country's GDP, but SMEs also face challenges and constraints due to their size. Available resources must be managed and spent wisely. To be more competitive, SMEs often turn to innovation to develop new products and services that can help them grow and be more relevant in the market. One can argue that innovation has become an imperative for business success. Open innovation practices are becoming more prevalent in organisations as a way to innovate. More organisations are adopting open innovation to gain wider access to knowledge and technology not otherwise available to them internally to the organisation or to appropriate value from their own knowledge and technology. Adopting these new innovation processes however requires a change to organisational and management practices. Research into open innovation in SMEs has generally lagged behind research in larger organisations. Available research does show that there are benefits to using open innovation by SMEs, but also that current open innovation practices tend to be ad hoc in nature and are usually not managed as a formalised approach. Open innovation is still an evolving field, especially in its application within SMEs. There is a requirement to develop a formalised approach to help SMEs navigate the adoption and use of open innovation within their organisations. This dissertation follows a design science research method to develop such an approach that SMEs can use for the implementation, execution and improvement of open innovation within their organisations. First, the need for such an approach was established through a review of the literature and a study of South African SMEs. Thereafter, a series of design cycles was undertaken to develop various artefacts to form an integrated open innovation approach. The approach consists of an open innovation life cycle framework, design propositions with detailed descriptions filling out the framework and a toolset of templates that help users better interact with the content of the approach. Following the design science research method, a practical solution was sought for a real field problem. It is grounded in the philosophical paradigm of pragmatism and balances the need to develop theory and application.
The base of the pyramid: a growth framework for SMME action
(Stellenbosch : Stellenbosch University, 2017-12) Van der Merwe, Michael David; Grobbelaar, Sara; Schutte, Cornelius Stephanus Lodewyk ; Von Leipzig, Konrad; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: A key challenge faced by South African enterprises operating in the market made up of the poorest socio-economic segment, namely the Base of the Pyramid (BOP), pertains to the difficulty of achieving sustained profitable growth whilst simultaneously promoting sustainable poverty alleviation. This study focuses on how growth promoting factors might be incorporated into a cohesive framework to provide consultants, enterprise owners, and academics alike with a means by which to guide Small, Medium and Micro-sized Enterprises (SMMEs) operating in the BOP towards attaining higher, lasting growth and socio-economic development. Existing enterprise growth models and frameworks have been found wanting in terms of their ability to cater for the unique approach necessary for navigating through the adverse and atypical conditions prevalent at the BOP. Grounded on an empirically backed literature base arrived at via a systematic literature review, an expansive list of antecedents to enterprise growth, i.e. growth factors, was developed. These factors, when addressed appropriately, have previously been shown to improve enterprise growth. This study therefore addressed the development of a framework to aid enterprises in simultaneously promoting for-profit growth and maximising sustainable impact in the BOP. The systematic literature review revealed 25 growth factors, of which five were within this study’s scope in that they are business strategy related and within direct control of the enterprise. The five growth factors are: business modelling for detailed planning; following a suitable and detailed business strategy for long-term growth; utilising innovation to consistently create value and respond rapidly to market changes; implementing good marketing practices to ensure maximum value delivery to customers, and; forming strategic alliances to bolster core competencies, leverage resources, and scale operations. Furthermore, pursuing sustainable development was determined as crucial to ensuring both lasting profitability and social impact is realised. Guided by the tenets of Soft Systems Methodology (SSM), the framework was iteratively developed by synthesising the BOP requirements with conventional growth factor processes, verifying the preliminary framework, and incorporating validation findings in its final design. Framework validation entailed four mechanisms, namely conducting: a retrospective case study to determine credibility and confirmability; expert screening interviews to ensure it is efficable, efficient, effective, and ethical; a survey of 57 for-profit South African enterprises to empirically establish need, reliability, relevance, and usefulness, and; expert focus interviews to maximise usability by identifying key stakeholder requirements within the framework. All routes validated the framework for use as a consultative tool in guiding SMME owners towards improved growth at the BOP. The unique contribution is embodied in: the framework’s novelty, combining multiple fields of knowledge pertaining to success at the BOP and in traditional markets into a cohesive whole for the first time; the confirmed practical significance of the framework requirements in that it provides users with an empirically vetted procedure for increasing growth potential as evidenced by the survey data, and; the optimised usability due to the visually clear framework, the easy to use evaluation scorecard, and incorporation of key focus areas for dealing with key stakeholders.
Bi-objective generator maintenance scheduling for a national power utility
(Stellenbosch : Stellenbosch University, 2017-03) Lindner, Berndt Gerald; Van Vuuren, J. H.; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: One of the key focus areas for the management of a power utility in a regulated energy market is planned preventative maintenance of the power generating units in its power system. The so- called generator maintenance scheduling (GMS) problem refers to finding a schedule according to which the planned maintenance can be performed on the generating units in a power system. A novel bi-objective optimisation model is proposed in this dissertation for the GMS problem in which demand satisfaction reliability is maximised and electricity production cost is minimised. The first scheduling objective is one of the most common objectives in GMS problems in the literature, namely minimising the sum of squared net reserve levels. This objective serves to create an even (reliable) margin of generating capacity over expected demand. The second scheduling objective is the (linear) production cost associated with a maintenance plan of all the generating units in a system. The latter objective is aimed at exploiting the following correlation: planning maintenance on a cost-efficient power station during a high-demand period incurs a higher fuel cost. Production cost is simply taken as fuel cost in this dissertation since it is the most prominent production cost component of power generation. Dominance-based multi-objective simulated annealing is adopted as model solution technique. Solving the aforementioned model clearly demonstrates that maintenance schedules which min- imise the sum of squared reserves are typically also associated with low production costs, but that the lowest sum of squared reserves maintenance schedule does not necessarily achieve the lowest production cost (a sentiment also reported in the literature). Hence there is a need for adopting a multi-objective modelling approach in the context of GMS problems in search of trade-off solutions rather than adopting a standard single-objective modelling paradigm. A sensitivity analysis is performed in respect of model constraint relaxations and the degree of constraint violations. In the process, certain soft constraints which sensitively influence the model objectives are identified. A decision support system, whose working is based on the bi-objective optimisation model described above, is designed and a concept demonstrator of this system is implemented on a personal computer. This concept demonstrator may be used to find and analyse trade-off solutions to instances of the GMS model and offers interactive features which facilitate sensitivity analyses in a very natural way. The viability and practical use of the concept demonstrator is finally illustrated by applying it to two realistic GMS case studies. It is found that the decision system is capable of producing high-quality sets of trade-off maintenance schedules in each case.
Bus route design and frequency setting for public transit systems
(Stellenbosch : Stellenbosch University, 2022-04) Husselmann, Gunther; Van Vuuren, Jan Harm; Andersen, Simen Johann; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: The availability of effective public transport systems is increasingly becoming an urgent problem in urban areas worldwide due to the traffic congestion caused by private vehicles. The careful design of such a transport system is important because, if well designed, such a system can increase the comfort of commuters and ensure that they arrive at their destinations timeously. A well-designed public transport system can also result in considerable cost savings for the operator of the system. The problem considered in this dissertation is that of designing three mathematical models for aiding a bus company in deciding upon efficient bus transit routes (facilitated by the first two models) and setting appropriate frequencies for buses along these routes (facilitated by the third model). The design criteria embedded in the first model (for designing bus routes) are the simultaneous pursuit of minimising the expected average passenger travel time and minimising the system operator’s cost (measuring the latter as the sum total of all route lengths in the system). The first model takes as input an origin-destination demand matrix for a specified set of bus stops, along with the corresponding road network structure, and returns as output a set of bus route solutions. The decision maker can then select one of these route sets subjectively, based on the desired trade-off achieved between the aforementioned transit system design criteria. This bi-objective minimisation problem is solved approximately in three distinct stages — a solution initialisation stage, an intermediate analysis stage and an iterative metaheuristic search stage during which high-quality trade-off solutions are sought. A novel procedure is introduced for the solution initialisation stage aimed at effectively generating high-quality initial feasible solutions. Two metaheuristics are adopted for the solution implementation, namely a dominance-based multi-objective simulated annealing algorithm and an improved non-dominated sorting genetic algorithm. The second model is a novel approach towards establishing high-quality bus routes resembling a reference set of bus routes (typically the currently operational bus routes) to varying degrees, providing the decision maker with bus route design alternatives that may be implemented incre mentally in order to limit the disruption experienced by passengers in the bus transit network. The objectives pursued in this model are the simultaneous minimisation of the expected aver age passenger travel time and the minimisation of a reference-route-to-design-route similarity measure. The second model takes the same input as the first model above, with the addition of a reference route set with which to compare alternative design routes in terms of similarity, and provides as output a set of trade-off solutions according to this model’s design criteria. The same three-stage approximate solution methodology described above is adopted for this model, and the same two metaheuristic implementations are utilised to solve instances of this new model. In the third model, high-quality bus frequencies are sought for each bus route in pursuit of min imising the expected average travel time for passengers (including waiting time, transfer time and travel time) and simultaneously minimising the total number of buses required by an operator to maintain the specified frequencies. The third model takes as input all the data required by the first model, along with a route set for which frequencies should be set, and returns as output a set of bus frequencies at which buses should operate along the various routes, based on a de sired trade-off between the aforementioned two design criteria. The solution approach adopted for this bi-objective minimisation problem again conforms to the three aforementioned distinct stages, with the exception that only a non-dominated sorting genetic algorithm is designed for solving it. The first and third models are finally applied to a special case study involving real data in order to showcase the practical applicability of the modelling approach.
A carbon mapping framework for the international distribution of fresh fruit
(Stellenbosch : Stellenbosch University, 2023, 2023-03) Du Plessis, Martin Johannes; Van Eeden, Joubert; Goedhals-Gerber, Leila Louise; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: The emissions impact of distributing goods such as fresh fruit is increasingly attracting attention due to the heightened awareness of greenhouse gas (GHG) emissions. However, despite the importance of freight logistics, assessing how transportation, handling, and storage of goods produce emissions, is largely an underdeveloped field. This is predominantly the result of a lack of practical industry guidance. The distribution of fresh fruit exported from South Africa is one such process that requires a standardised and accurate method to determine GHG emissions. The primary aim of this dissertation was to develop a carbon mapping framework and emission intensity factors for the international distribution (transportation, handling, and storage) of fresh fruit from South Africa. The framework and factors should enable any stakeholder with reasonable knowledge to calculate the carbon footprint (kg CO2e/kg of fruit) and the total emissions (kg CO2e) produced by the various distribution activities from a packing facility up until the port of discharge. To achieve this primary aim, several research objectives (ROs) were satisfied using a well-defined mixed methods research approach. This mixed methods approach was ideal since it enabled the triangulation of quantitative and qualitative input data. The sources of data included literature, observations, emission intensity factors developed from primary data collected from industry, distribution chain diagrams, semi-structured interviews with subject matter experts (SMEs), collaboration with the fruit export industry, and the iterative application of the framework to validate typical distribution scenarios by which fresh fruit is exported. The large number of different inputs enabled constant and continuous verification of each part of the research, thereby ensuring the subsequent results' validity and research rigour. Apart from the validation of each part of the research by SMEs, the validity of the research was also confirmed by the five journal articles included in the dissertation document. The application of the developed carbon mapping framework and associated emission intensity factors showed that the carbon footprint for scenarios where deep-sea ocean transport is used as mode for the main carriage varies between 0.31 and 0.84 kg CO2e/kg of fruit. If air transportation is used as mode for the main carriage, the carbon footprint can be up to 11.35 kg CO2e/kg of fruit. These results are, however, scenario-specific and depend on the transportation mode, the number of activities performed during the pre-carriage phase, the duration of storage, the packaging configuration of fruit, the transportation distances, and the origin-destination pair, amongst other things. However, it is certain that the distribution of fresh fruit, like many other commodities, emits a significant amount of emissions, necessitating urgent decarbonisation. The carbon mapping framework and emission intensity factors developed in this research not only set a standard for the South African fruit export industry to estimate distribution emissions but also provides other commodity groups with guidance to develop a similar emission accounting standard. With global freight volumes growing due to globalisation and economic progress, practical tools such as this framework are now more important than ever for understanding the emission impact of logistical decisions and freight distribution.
A competitive strategy framework for E-business start-ups
(Stellenbosch : Stellenbosch University, 2015-12) Ungerer, Gerard David; Schutte, C. S. L.; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: The strategic tools and insights that e-business start-ups require to better formulate their competitive strategies are obscured by the staggering amounts of strategy literature that is available. Yet at the same time, given the relative recency of the Internet, research in the e-domain is still in its infancy. An opportunity for strategic sense-making and integration was therefore identified to make these tools and insights more accessible, while simultaneously deepening the understanding of e-business. The objective of this study was to develop a conceptualisation that could assist e-business start-up competitive strategy formulation. Competitive strategy in this context refers to how a business intends to compete in the market and how it intends to defend its chosen competitive position. In conducting the research, a constructivist philosophical perspective and a practice-oriented approach was embraced, which required the developed conceptualisation to present a more informed and sophisticated perspective than previously existed, while also providing practical utility in the real world. A basic systems engineering process was followed for this exploratory theory building study. This involved creating a set of requirements that needed to be met by the conceptualisation, designing the conceptualisation and its sub-models, and verifying and validating that the conceptualisation met the requirements. The research endeavour investigated four main domains of interest, namely e-business, business models, blue ocean strategy and red ocean strategy. Four sub-domains were also investigated, namely fundamentals of e-business strategy, business model innovation, e-value creation and e-customer retention. Together these domains produced 46 content requirements that needed to be addressed in addition to the 17 research question requirements and 18 theoretical model building requirements. The output of the study was a competitive strategy framework that exists on three levels of complexity. It consists of five primary elements (customer need exploration, value proposition, customer lock-in, strategic assessment, renewal and growth), nine sub-elements, 18 sub-models, various relationships and a flexible sequence. The validation process (local, international and via workshops) confirmed that the developed competitive strategy framework has achieved its goal and is capable of assisting e-business start-up competitive strategy learning, formulation and analysis, resulting in enhanced cognition. In addition, e-business practitioners regarded the framework as a better methodology for formulating competitive strategies than their previous approaches. This study scratches at the surface of all the aspects and complexities related to competing in the e-domain. The competitive strategy framework for e-business start-ups, however, is an important stepping stone towards developing a better understanding of the e-environment itself, how to formulate business strategies for this environment and how to successfully compete within it.
Concentrating Solar Power (CSP) technology adoption in South Africa
(Stellenbosch : Stellenbosch University, 2018-12) Craig, Omotoyosi; Brent, Alan C.; Dinter, Frank; De Kock, Imke; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: South Africa (SA) aims to generate 42 per cent of its electricity from renewable energy technology sources by 2030. To achieve this target, the government started the Renewable Energy Independent Power Producer Procurement Programme (REI4P) to allow easy integration of renewable energy technologies into the existing energy mix. The country has an abundant solar resource, and the potential to harvest this resource through concentrating solar power (CSP) has been proven. In 2010, concentrating solar power (CSP) was one of the major renewable energy technologies that was prioritised by SA, and as a result 600 MW of CSP have been bought in the REI4P, and this includes seven plants that have been, or are being, built. Conversely, recent events have shown that the future of CSP in South Africa looks bleak, as the government’s recent Integrated Resource Plan (IRP) updates gave no allocation to new CSP plants beyond 2030. Several factors have contributed to the chasm in the adoption of CSP technology in the country. Very few CSP plants are connected to the grid, and there is limited research and literature on its learning effect and economics of scale. Also, the impacts of this technology on South Africa’s trade and the local manufacturing industries, as well as on the local research, development, and innovation community, have not been investigated to date. This research presents a detailed analysis of the CSP technologies in South Africa in terms of the existing technology adoption models and diffusion strategies, used by government and its agencies, to improve the development and deployment of these technologies. The study also analyses the state of CSP, concerns, and complex issues limiting the deployment of the technology in the country. The study then uses mathematical relationship to determine the progress ratio, the learning effect, and the likely future of CSP in the country. The impact of the CSP technology on economics and trade were then quantified and a technology specific roadmap was developed. The innovation analysis carried out on CSP technologies in South Africa shows that its tariff is currently higher than that of other major RETs (wind and PV), and that the innovation experience of the CSP technology is incremental, as each subsequent plant was an improvement on previous facilities elsewhere. The development of research into innovation, and eventually into market products of CSP systems, is improving with a closer relationship and working together of the stakeholders. This progress, however, is slow, because of the limited knowledge in identifying and understanding the important activities and policy instruments that can aid the prioritisation of important actions to forge better relationships among stakeholders, and fast track the deployment of CSP. The expert elicitation analysis on the impact of RD&D funding on the present and future cost of electricity from CSP presents a RD&D investment strategy that will foster technological improvement and adoption of CSP in the country. Three RD&D funding scenarios are presented and analysed, and an allocation procedure was developed. The results show that strategic policies, laws and the right funding can help South Africa to fully maximize its CSP resources potential to foster cost reduction and market viability of its solar innovations. The result from the systems dynamics analysis shows that improved support for research is the most effective way to open new methods and ways in which the CSP technologies can be deployed, which will foster further CSP adoption in in the country. Further analysis, based on the data from literature and existing plants, highlights the current state of CSP in South Africa for capacity and costs. The economic indicators of CSP, which include LCOE, LPOE, DNI, and specific costs, are discussed, and the most realistic future cost of CSP in SA is presented. Limitations to the learning effect of CSP in SA are identified; existing principles were used with limited data to develop the learning rate, progress ratio, and cost reduction rate of CSP. The study shows that there are no existing patterns in the capital costs of the existing CSP plants in SA for technology, size, solar multiple, site location, or storage capacity; this makes the experience curve analysis of the CSP industry difficult. The solar field cost, which is the most significant capital cost, was analysed independently to give an idea of what the CSP experience curve might look like. The CSP learning rate in SA was calculated, the future of capital costs was then determined, and the likely experience curve for CSP in SA was presented. The assessment of the SA local manufacturing capabilities for CSP related services identified strength and the challenges of the sector. It further estimated the economic and social benefits of improvements, including the employment opportunities, and the overall impacts on trade and economy. A technology specific roadmap was developed in this study to present a framework for the medium term CSP adoption outlook in South Africa.
A congruence analysis of innovation platforms from the innovation ecosystems and value chains perspectives
(Stellenbosch : Stellenbosch University, 2021-12) Dondofema, Richmore Aron; Grobbelaar, Sara Saartjie; Herselman, Marlien; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering.
AFRIKAANSE OPSOMMING: Geleenthede moet in Suid-Afrika se landelike gemeenskappe geskep word vir die burgers om ten volle deel te neem aan die land se ekonomiese, sosiale en politieke lewe, ten einde armoede te oorkom. Die grootste uitdaging vir landelike ontwikkeling in Suid-Afrika is die marginalisering van die armes. Mense moet toegang hê tot basiese dienste van hoë gehalte wat hulle in staat stel om goed gevoed, gesond en toenemend vaardig te wees. Die Nasionale Ontwikkelingsplan (NOP) 2030 erken dat landelike ekonomieë deur die landbou ondersteun moet word. Die rol van innovasie en die belangrikheid daarvan om verbeterde dienste en volhoubare ontwikkeling te bewerkstellig, word algemeen erken en is ook deur die SDG9 as 'n prioriteit geïdentifiseer in die Doelwitte vir Volhoubare Ontwikkeling. Innovasie kan ekonomiese groei en indiensneming ondersteun, lewensonderhoud op voetsoolvlak skep en regeringsprestasies en dienslewering verbeter. Hoewel innovasie nie die enigste faktor is wat ekonomiese groei, industrialisering en inklusiewe ontwikkeling bevorder nie, bly dit 'n beduidende en belangrike katalisator tot ekonomiese groei. Innovasie kan die ontwikkeling van Suid-Afrika asook die burgers se lewensgehalte verbeter, veral in landelike en arm gemeenskappe. Daar is 'n toenemende belangstelling in die uitbreiding van innovasie as konsep en om innovasie vir inklusiewe ontwikkeling (innovasie tot maatskaplike voordeel en die openbare belang) in Suid-Afrika, in te sluit. Die openbare sektor moet 'n instaatstelling van innovasie vir inklusiewe ontwikkeling word. Innovering vir 'n inklusiewe ontwikkelingsbenadering behels die uitbreiding van die verskeidenheid belanghebbendes en die verdieping van hul beraadslagende beplanningsbetrokkenheid. Innovasieplatforms wat ruimte bied vir samewerking met verskeie belanghebbendes, is nodig om landelike gemeenskappe te dryf om die NDP 2030-doelwitte te bereik. Hierdie studie het bygedra tot die wetenskaplike gesprek deur 'n analitiese sintesekaart vir innovasieplatforms te ontwikkel vanuit die waardekettingperspektief en die innovasie- ekosisteemperspektief. Die studie het gefokus op die funksionering van innovasieplatforms. Die studie is gelei deur die metodologie van kongruensie-analise wat deur Blatter (2012) ontwikkel is. Kongruensie- analise laat konseptuele verfynings toe met 'n hoë geldigheidsvlak oor 'n klein aantal gevalle. Dit word bereik deur spesifieke stellings en waarneembare afleidings uit abstrakte teorieë te interpreteer. Die benadering is teoriegerig en gebruik gevallestudies om insiggewende bydraes te lewer. Blatter (2012) se kongruensie-analisemetodologie kom tekort vir die vereistes van hierdie studie en dit moes uitgebrei word om elemente uit Jabareen se metode van konseptuele raamwerkontwikkeling te betrek wat 'n sistematiese literatuuroorsig en aktiwiteitsanalise-metode insluit. Die keuse van gevallestudies is gedoen deur gebruik te maak van gemaksteekproefneming, en die kongruensie-analise is op Vrugte Suid Afrika-innovasieplatform en op die Digital Doorway-innovasieplatform gedoen. Die studie het analitiese pluralisme gebruik om nuttige insigte te verkry en innovasieplatforms beter te verstaan. Besprekings uit hierdie studie ondersteun dat die perspektief van die innovasie-ekosisteem asook die perspektief van die waardeketting, beide belangrike analitiese perspektiewe in innovasieplatforms is. Die twee perspektiewe bring verskillende insigte in die geval waar dit toegepas word op dieselfde gevallekontekste, soos deur hierdie studie aangedui. Ons sien ook dat die insigte wat deur elke lens bewerkstellig word, verskillende bevindinge vir twee gevallestudies uit verskillende kontekste (dit wil sê landbou- en landelike ontwikkelingsektore in Suid-Afrika) uitlig.
Constructing a framework that facilitates technology transfer to sub-Saharan Africa : a healthcare perspective
(Stellenbosch : Stellenbosch University, 2020-04) Marais, Rian; Grobbelaar, Sara; De Kock, Imke; Stellenbosch University. Faculty of Industrial Engineering. Dept. of Industrial Engineering.
ENGLISH ABSTRACT: Healthcare technology transfer aims to alleviate healthcare burdens in developing nations through a combination of acquisitions and collaborative technology development. Although technology transfer may be viewed as a mature field and while various technology transfer models exist, few focus on health-related concepts in developing nations. This study sets out to develop a framework capable of facilitating health-related technology transfer to sub-Saharan Africa. A systematic conceptual literature review is conducted to identify the major characteristics of technology transfer. The review outlines the evolution of technology transfer, critical technology transfer stakeholders and their roles, the available technology transfer methods, the requirement for knowledge transfer as well as known technology transfer barriers. A systematic comparative literature review is conducted to refine the focus of the study towards healthcare technology transfer case studies completed in sub-Saharan Africa. Fifty-one case studies are compared to identify the required infrastructure components, technology transfer methods utilised as well as the stakeholders involved. Based on the outcomes of the literature reviews, a conceptual framework is developed. This framework is divided into five phases and aims to guide a user through the phases of technology development, technology analysis, technology transfer method application, change management and commercialisation. Multiple guidelines and managerial best practices are provided at each phase. The conceptual framework is evaluated using an evaluation procedure consisting of three levels. The first level utilises the outcomes of 16 semi-structured interviews conducted with healthcare and technology transfer industry experts. The second level utilises the outcomes of a survey instrument completed by 89 healthcare technology managers. The conceptual framework is retrospectively applied to three healthcare TT case studies for the third level of the evaluation procedure. Issues identified during this evaluation procedure are mitigated by conflating the outcomes into the existing framework. The final consolidated framework is presented along with individual phase expansions.
A critical success factor model for asset management services
(Stellenbosch : Stellenbosch University, 2014-12) Jooste, Johannes Lodewyk; Vlok, P. J.; Schutte, C. S. L.; Stellenbosch University. Faculty of Engineering. Department of Industrial Engineering.
ENGLISH ABSTRACT: Business-to-business services relating to physical asset management are playing an increasingly important role in industry. This is in the midst of the current pressures which asset owning organisations are experiencing in realising optimal value from their assets. The pursuit of understanding and complying with asset management standards such as ISO 55000 as well as the potential value to be gained from successful and sustainable business relationships contributes towards the importance of these services. The problem is that there is little or no evidence regarding the critical success factors for collaborating successfully in asset management services. The study identi es these critical success factors and demonstrates how the factors can di er between role players, industries, global regions and service types. A decision support model is developed providing the asset management community with access to the critical success factors for decision-making purposes. Based on the synthesis from internationally conducted Delphi- and survey studies it is found that the continued and sustained commitment from the asset owning organisation's senior management in support of the asset management service is the most critical factor for a successful asset management service partnership. Open and e ective communication is also highlighted as being critical, while it is important to have a process in place to improve the service continuously. Laboratory and eld testing con rm the validity of the decision support model for facilitating the decision-making process to improve asset management services, and in addition it also formalises the commercial and contracting processes relating to these services.

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