Electrical energy has become a very important and integrated part of the current era. Electricity cost saving interventions, such as load shifting, form part of demand side management (DSM) interventions. DSM interventions have been successfully implemented in the past to ensure reliable supply of electricity during the Eskom peak periods. It has been established that there is a need to implement an electricity cost saving intervention on a large water distribution utility. This dissertation focuses on the integration of electricity cost saving interventions on a water distribution utility. An investigation methodology, as well as an integration strategy for implementing an electricity cost saving intervention were developed. This study expands on the importance of an integrated approach. It further discusses the shortcomings of the current control philosophies of a large water distribution utility in South Africa. A load shifting project was implemented as an electricity cost saving intervention on a large water distribution utility in South Africa. The proposed integrated strategy was simulated and an optimised approach developed. It was found that the implementation of the strategy was limited due to process constraints and increasing water demand. Utilising the large combined installed capacity of the pumps in the water distribution utility and the storage capacity, the strategy was implemented and cost savings obtained. It was concluded that load shifting was possible on individual pumping stations in the water distribution utility subsystems, and could, therefore, be quantified to an integrated approach. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

Mathematical analyses indicated that significant possibilities exist for load shifting projects on a Large Potable Water Utility (LPWU) in South Africa. A primary concern remained, i.e. whether the load variation would have an effect on the water quality. Extensive simulation and testing were initiated in order to prove that the load shift will not affect the water quality. In South Africa, the highest standard for drinking water is the Blue Drop award. The LPWU has received this award multiple times and strives to maintain it. An investigation was launched to determine if this load shifting project would have an effect on the quality standards to which the utility holds (SANS 241 (2011)). The LPWU has over 3000 km of pipelines to supply potable water to the industrial heartland of the country as well as millions of domestic users. The LPWU network is the longest pumping network in the world and is still expanding. The investigation included a simulation of a pumping simulation package to determine how the system would react to the changes. In this simulation, the load reduction in terms of Mega litre per day (Ml/day) was established. Results were compared to the normal operating parameters of the Water Treatment Works (WTW). The mathematical analysis in this investigation concluded that an evening peak load shift of 24.5 MW is achievable. This dissertation will emphasise the necessity of a detailed investigation. The investigations and simulation will determine that the volume of water is well within the operating parameters of the WTW. Studies were done on each area of the plant. In-depth conversations with WTW personnel revealed that the reduction of the volume of water in question will not have an effect on the water quality. Further, it was established that it would be possible to use the sumps of the water treatment works to achieve the desired load shift. By using the sumps of the WTW, a load shift can be done without stopping any process in the WTW with the exception of disinfection at the Booster Pump Stations (BPS), where the balancing reservoirs were used as buffer capacity. The investigation shifted to establish whether stagnant water and a change in dosage would have an effect on the water quality in regard to the reduction and recovery load. As expected, the water never became stagnant at any moment due to the fact that only a small portion of the load was reduced. The water quality and dosage report of the water utility was used and compared to normal operations. The planned load shift had no effect on any aspects of the water quality. The project is feasible and will reach the set targets without affecting the water quality. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

Electrical energy has become a very important and integrated part of the current era. Electricity cost saving interventions, such as load shifting, form part of demand side management (DSM) interventions. DSM interventions have been successfully implemented in the past to ensure reliable supply of electricity during the Eskom peak periods. It has been established that there is a need to implement an electricity cost saving intervention on a large water distribution utility. This dissertation focuses on the integration of electricity cost saving interventions on a water distribution utility. An investigation methodology, as well as an integration strategy for implementing an electricity cost saving intervention were developed. This study expands on the importance of an integrated approach. It further discusses the shortcomings of the current control philosophies of a large water distribution utility in South Africa. A load shifting project was implemented as an electricity cost saving intervention on a large water distribution utility in South Africa. The proposed integrated strategy was simulated and an optimised approach developed. It was found that the implementation of the strategy was limited due to process constraints and increasing water demand. Utilising the large combined installed capacity of the pumps in the water distribution utility and the storage capacity, the strategy was implemented and cost savings obtained. It was concluded that load shifting was possible on individual pumping stations in the water distribution utility subsystems, and could, therefore, be quantified to an integrated approach. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

Mathematical analyses indicated that significant possibilities exist for load shifting projects on a Large Potable Water Utility (LPWU) in South Africa. A primary concern remained, i.e. whether the load variation would have an effect on the water quality. Extensive simulation and testing were initiated in order to prove that the load shift will not affect the water quality. In South Africa, the highest standard for drinking water is the Blue Drop award. The LPWU has received this award multiple times and strives to maintain it. An investigation was launched to determine if this load shifting project would have an effect on the quality standards to which the utility holds (SANS 241 (2011)). The LPWU has over 3000 km of pipelines to supply potable water to the industrial heartland of the country as well as millions of domestic users. The LPWU network is the longest pumping network in the world and is still expanding. The investigation included a simulation of a pumping simulation package to determine how the system would react to the changes. In this simulation, the load reduction in terms of Mega litre per day (Ml/day) was established. Results were compared to the normal operating parameters of the Water Treatment Works (WTW). The mathematical analysis in this investigation concluded that an evening peak load shift of 24.5 MW is achievable. This dissertation will emphasise the necessity of a detailed investigation. The investigations and simulation will determine that the volume of water is well within the operating parameters of the WTW. Studies were done on each area of the plant. In-depth conversations with WTW personnel revealed that the reduction of the volume of water in question will not have an effect on the water quality. Further, it was established that it would be possible to use the sumps of the water treatment works to achieve the desired load shift. By using the sumps of the WTW, a load shift can be done without stopping any process in the WTW with the exception of disinfection at the Booster Pump Stations (BPS), where the balancing reservoirs were used as buffer capacity. The investigation shifted to establish whether stagnant water and a change in dosage would have an effect on the water quality in regard to the reduction and recovery load. As expected, the water never became stagnant at any moment due to the fact that only a small portion of the load was reduced. The water quality and dosage report of the water utility was used and compared to normal operations. The planned load shift had no effect on any aspects of the water quality. The project is feasible and will reach the set targets without affecting the water quality. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

I syfte att undersöka vad som påverkar medarbetarattityder till en intervention, genomfördes en enkätstudie med 23 frågor inom två kommunala verksamhetsprocesser. Bland 137 besvarade enkäter och en svarsfrekvens på 77 procent var deltagarna mellan 22 och 64 år med olika utbildningsnivåer och omfattning på chefskontakt. Frågeställningen var: Hur påverkas medarbetarnas attityder av 1) chefens engagemang, 2) yrkes- och arbetsplatsfaktorer och 3) arbetsbelastning. Genom varians-, korrelations- och regressionsanalyser undersöktes de oberoende variablernas förhållande till medarbetarnas attityder till interventionen. Resultatet visade att medarbetarattityderna till interventionen var mer positiva när chefens engagemang uppfattades som högt. En negativ inställning till interventionen bland kollegorna på arbetsplatsen visade samband med en mer negativ medarbetarattityd. Studien gav inte stöd för något samband mellan arbetsbelastning och medarbetarattityd. Ett klusterurval hade eventuellt ökat validiteten och förbättrat könsfördelningen. Förslag till vidare forskning är att undersöka påverkan av upplevd nytta på sambandet mellan arbetsbelastning och attityd till förändring.

Most research on Cognitive Load Theory (Sweller, 1988) has uncovered many instructional design considerations for learning complex tasks. Additionally, the Community of Inquiry (Garrison, Anderson, & Archer, 2000) framework describes many of the learning experiences in online education. A gap existed in the literature for investigating cognitive load over the duration of a college algebra course and for investigating the relationship between cognitive load and cognitive presence. This research study has addressed this gap by investigating cognitive load and cognitive presence in an online and face-to-face college algebra course. The results of this study revealed that face-to-face students earned statistically significant higher final course grades and homework grades than the online students. The face-to-face math course was slightly more efficient because it produced learners who exerted similar cognitive load as learners in the online course but the learners in the face-to-face earned higher performance score. Online discussion prompts that ask student to apply their solution or defend their solution engaged students in cognitive presence differently. When students were prompted to apply their solution to a real world scenario, most students reached resolution in their initial posts, but they were often not cognitively present in their follow-up posts. When students were prompted to provide a defense of their solution, most of the posts demonstrated cognitive presence, but not as many individual students reached resolution. Additionally, students progressed through the stages of cognitive presence when an instructor asked them a specific question about their math problem or real life scenario in a timely manner. When instructors post questions to their students that directly ask for an application of their hypothesis or an explanation how they arrived at their hypothesis, students can reach the highest stage of cognitive presence. When instructors post messages that reach the highest stage of cognitive presence, students do not post messages that reach the highest stage of cognitive presence. Lastly, this study did not find a strong linear relationship between cognitive presence and cognitive load.

Latent Dirichlet Allocation (LDA), a total probability generative model, is a three-tier Bayesian model. LDA computes the latent topic structure of the data and obtains the significant information of documents. However, traditional LDA has several limitations in practical applications. LDA cannot be directly used in classification because it is a non-supervised learning model. It needs to be embedded into appropriate classification algorithms. LDA is a generative model as it normally generates the latent topics in the categories where the target documents do not belong to, producing the deviation in computation and reducing the classification accuracy. The number of topics in LDA influences the learning process of model parameters greatly. Noise samples in the training data also affect the final text classification result. And, the quality of LDA based classifiers depends on the quality of the training samples to a great extent. Although parallel LDA algorithms are proposed to deal with huge amounts of data, balancing computing loads in a computer cluster poses another challenge. This thesis presents a text classification method which combines the LDA model and Support Vector Machine (SVM) classification algorithm for an improved accuracy in classification when reducing the dimension of datasets. Based on Density-Based Spatial Clustering of Applications with Noise (DBSCAN), the algorithm automatically optimizes the number of topics to be selected which reduces the number of iterations in computation. Furthermore, this thesis presents a noise data reduction scheme to process noise data. When the noise ratio is large in the training data set, the noise reduction scheme can always produce a high level of accuracy in classification. Finally, the thesis parallelizes LDA using the MapReduce model which is the de facto computing standard in supporting data intensive applications. A genetic algorithm based load balancing algorithm is designed to balance the workloads among computers in a heterogeneous MapReduce cluster where the computers have a variety of computing resources in terms of CPU speed, memory space and hard disk space.

Recent studies of non-conscious processing have indicated that visually processed non-conscious informationcan be used to influence behaviour after as much as 5000 ms. This study further explores the possibilities of nonconsciousvisual working memory retention. Twelve participants were in this study instructed to memorizemasked faces and then make decisions based on what they believe they saw or guess intuitively. Results indicatethat increased working memory load only affected conscious trials, suggesting non-conscious stimulus remainedunperceived. Since no consciousness effect was observed when measuring response times of congruent trials thisstudy do not support non-conscious working memory retention. / Nya studier av undermedvetet processande har indikerat att visuellt behandlad undermedveten information kananvändas för att påverka beteende efter så mycket som 5000 ms. Denna studie undersöker även möjligheternavad gäller undermedveten inlagring i det visuella arbetsminnet. Tolv deltagare fick i denna studie i uppdrag attmemorera maskade ansikten och sedan fatta beslut utifrån vad de tror att de såg eller gissa intuitivt. Resultatentyder på att ökad belastning av arbetsminnet påverkar endast medvetna försöksomgångarna, vilket tyder på ickemedvetnastimuli förblev osedda. Eftersom ingen medvetandeeffekt observerades vid svarstiderna underkongruenta försök stöder inte denna studien undermedveten lagring av arbetsminnet.

Tendon injuries are ubiquitous in the sporting and occupational environment. Clinically they present a challenge to Orthopaedic surgeons as they account for up to half of all sports injuries and almost half of reported work related ailments. The capacity for tendons to heal subsequent to injury is restricted due to their poor blood supply. Moreover, healed tendon tissue may be inferior to the intact tendon, having diminished biochemical and biomechanical properties and this brings about an ever increasing need for optimized treatment methods for tendon repair. Mechanobiology is concerned with how mechanical forces influence physiological and pathological aspects of the living tissue. However, the complex and poorly controlled loading environment in living organisms prevent the establishment of direct relationships between mechanical stimuli and tissue response. By developing a novel in vitro loading system (IVLS), the work in this thesis investigates the potential of a new and exciting biophysical loading intervention, High Frequency Low Magnitude (HFLM) mechanical loading, for stimulation of tendon repair and remodelling. Following a pre-defined stimulation period, healthy rat tail tendon fascicles (RTTFs) were evaluated for tissue viability and metabolism, Glycosaminoglycan (GAG) content, collagen arrangement and tangent modulus, using staining and biochemical assays, together with microscopy techniques, and mechanical testing. HFLM mechanically loaded tendons showed a trend for a higher tangent modulus than fresh tissue, and significantly higher modulus than unloaded. Further, when varying mechanical loading parameters of frequencies and dosages over clinically relevant ranges, a frequency dependent response was observed with increased tangent modulus and GAG content with increasing frequency. An association between high tendon crimp pattern and elevated tendon modulus as a result of HFLM mechanical loading was also demonstrated. Concomitantly, an injury model was developed to evaluate the effects of in vitro static, low frequency cyclic and HFLM mechanical loading conditions on the biochemical and biomechanical properties of in vitro damaged tendons. HFLM mechanically loaded damaged tendons again demonstrated significantly higher modulus and metabolism than unloaded tissue, although these were reduced below those of fresh damaged tissue. The findings in this thesis together with the newly developed IVLS reveal the potential for an exciting and unique biophysical therapeutic loading intervention for treatment of tendon injuries, and provide a scientific platform for further investigation of the effects of HFLM mechanical loads, potentially leading to an application within the clinic for enhanced connective tissue repair and remodelling.

Although sitting is a large part of everyday life is the influence of the sitting positions and chair design on pressure and load distribution as well as comfort for transfemoral amputees quite unexplored. The aim of this study was therefore to examine this further. Two transfemorally amputated females (49 and 57 years old) participated in the study. Three positions were examined for each subject; sitting without foot support and sitting with the knee joints flexed 90◦ and 105◦. The pressure inside the socket was measured by two pressure sensors, placed distally and proximally on the posterior wall inside the socket. The lengthwise pressure distribution and the sidewise load distribution between the socket and the underlying material was measured by a pressure mat. In addition to this, the subjects answered a questionnaire regarding the subjective comfort for each position.  The result showed that the pressure underneath the socket were higher distally than proximally without foot support. The pressure transferred proximally as the knee became more flexed. The most even load distribution sidewise was found when the subjects sat with their knees flexed 105 degrees. Sitting with the knees flexed 90◦ was ranked as the most comfortable position. No conclusion could be made regarding the pressure inside of the socket. Additionally, according to this study the level of comfort does not have any clear relation with the sidewise load distribution or the longitudinal pressure distribution. / En stor del av livet spenderas sittandes, men den påverkan som sittposition och stoldesign har på tryckfördelning och komfort för transfemoralt amputerade är ganska outforskat. Studien ämnar därför undersöka detta. Två transfemoralt amputerade kvinnor (49 och 57 år) medverkade i studien. Tre sittpositioner undersöktes för varje testperson; sittande utan fotstöd samt sittande med knäleden i 90◦ respektive 105◦ flexion. Trycket inuti hylsan mättes med hjälp av två trycksensorer, som placerades distalt och proximalt på den bakre hylsväggen. Tryckfördelningen i längsriktningen och lastfördelningen i sidled mellan hylsan och underlaget mättes med en tryckmatta. Förutom detta svarade testpersonerna även på ett frågeformulär angående den subjektiva komforten för varje position. Resultatet visade att trycket under hylsan var högre distalt än proximalt när inget fotstöd användes. Trycket förflyttades proximalt då knät böjdes. Den mest jämna lastfördelningen mellan sidorna påträffades när knät var flekterat 105◦. Enligt frågeformuläret var den mest bekväma positionen den med 90◦ i knäleden. Ingen slutsats kunde göras angående trycket inuit hylsan. Ingen tydlig relation kunde heller inte hittas mellan den subjektiva komforten och tryck- eller lastfördelningen.