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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Integration of a vision-guided robot into a reconfigurable component- handling platform

Viljoen, Vernon January 1900 (has links)
Thesis (M. Tech.) -- Central University of Technology, Free State, 2010 / The latest technological trend in manufacturing worldwide is automation. Reducing human labour by using robots to do the work is purely a business decision. The reasons for automating a plant include: Improving productivity Reducing labour and equipment costs Reducing product damage Monitoring system reliability Improving plant safety. The use of robots in the automation sector adds value to the production line because of their versatility. They can be programmed to follow specific paths when moving material from one point to another and their biggest advantage is that they can operate for twenty-four hours a day while delivering consistent quality and accuracy. Vision-Guided Robots (VGRs) are developed for many different applications and therefore many different combinations of VGR systems are available. All VGRs are equipped with vision sensors which are used to locate and inspect various objects. In this study a robot and a vision system were combined for a pick-and-place application. Research was done on the design of a robot for locating, inspecting and picking selected components from a moving conveyor system.
42

Evaluation of the swat model in simulating catchment hydrology : case study of the Modder river basin

Tetsoane, Samuel Tshehla January 2013 (has links)
Thesis (M. Tech. (Civil engineering)) - Central University of Technology, free State, 2013 / Hydrological models have become vital tools for understanding hydrologic processes at the catchment level. In order to use model outputs for tasks ranging from regulation to research, models should be scientifically sound, robust, and tenable. Model evaluation is therefore beneficial in the acceptance of models to support scientific research and to guide policy, regulatory, and management decision-making. The objective of this study was to evaluate the performance of the SWAT model in simulating stream flow for the Modder River Basin. The study area is situated at -29° 11’ latitude and 26° 6’ longitude at an elevation of 1335 m and drains a land area of 949 km2. The land cover is mainly grassland (pasture) with other minor land use types. The climate of the area is semi-arid with Mean Annual Precipitation (MAP) of 563 mm. Two techniques that are widely used in evaluating models, namely quantitative statistics and graphical techniques, were applied to evaluate the performance of the SWAT model. Three quantitative statistics, namely Nash-Sutcliffe efficiency (NSE), percent bias (PBIAS), and ratio of the mean square error to the standard deviation of measured data (RSR), in addition to the graphical techniques, were identified to be used in model evaluation. Results of calibration and validation of the model at a monthly time step gave NSE of 0.65, Pbias of 15 and RSR of 0.4, while NSE of 0.5, Pbias of 31 and RSR of 0.5 were recorded for validation. According to monthly model performance ratings, the model performed well during calibration and performed satisfactory during the validation stage.
43

Radiation distribution in a private neurological theatre during invasive back pain management procedures

Van der Merwe, Belinda January 2008 (has links)
Thesis (M. Tech.) -- Central University of Technology, Free State, 2008 / The aim of the study was to determine radiation dose levels around the theatre table, on either side of the C-Arm, in order to establish if the radiation dose received by staff during back pain procedures fell within the limits set by the International Commission of Radiological Protection (ICRP). The question that arose from this goal was whether the stance of staff, in relation to the x-ray tube side of the C-Arm, influenced radiation dose levels. In order to apply the ALARA principle, the possibility of lowering the radiation dose in the neurological theatre was explored. The measurement methodology of the study was twofold: measurements were executed by means of TLD meters, as well as with an ionisation chamber. TLD meters were placed on the patient, the neurosurgeon and the radiographer during back pain procedures, and, more specifically, during fluoroscopy, to record the doses with the Image Intensifier (II) above the table as well as with the x-ray tube above the table, at the pelvis and the chest height of the staff. Ionisation chamber measurements were recorded in 25cm intervals around the theatre table with a phantom and the C-Arm positioned in the PA, oblique and lateral positions at 110cm and 133cm heights from the floor. The TLD results indicated that, when compared to the Image Intensifier side, the radiation dose was higher on the x-ray tube side of the C-Arm. The radiation dose was higher at the height closest to the x-ray source. The radiation dose received by the patient was higher with the x-ray tube positioned above the table (PA). The radiation dose to the surgeon’s hand and body was higher with the x-ray tube positioned above the table (PA). Radiation dose levels with the x-ray tube above the table during back pain procedures in the current theatre exceeded the occupational annual recommendation of 500mSv to the neurosurgeons hands, as recommended by the ICRP. The opposite is true with the II positioned above the table. The research question was answered positively in that the x-ray tube under couch orientation has the potential to limit dose levels during back pain procedures. The measurement values resulted in a proposed protocol in terms of positioning of staff and orientation of the C-Arm in order to apply the ALARA principle during back pain procedures. Constant revision of protocols is the responsibility of the radiographer in order to guarantee that the ALARA principle is implemented in every unique situation.
44

Modelling the catabolite and microbiological profile of cheddar cheese manufactured from ayrshire milk

Venter, Tania January 2010 (has links)
Thesis (D. Tech.) -- Central University of Technology, Free State, 2010 / Branded dairy products have lately become a global trend. As a result of this, the origin of the milk used in the manufacturing of branded cheeses must be declared by the producer, since it is known that these products are highly adulterated with foreign milk. In South Africa, branded Ayrshire Cheddar cheese has become highly popular due to its unique organoleptic properties and in light of claims that it ripens much faster than cheese made from other milk (not including Ayrshire). This study was therefore directed to investigate the unique properties of branded Ayrshire Cheddar cheese versus Cheddar cheese manufactured from a mixture of other breeds’ milk (not including Ayrshire milk) and to establish a catabolite profile for each cheese type. The outlay of the thesis was constructed into six chapters each with its own outcomes. The first chapter focused on the variations between the two Cheddar cheese batches (produced from Ayrshire and other breeds’ milk) with regards to organic acid, selected chemical parameters and starter microbiotia. In the following three chapters mathematical models were developed that would predict organic-; fatty and amino acid fluxtuations respectively in the cheese made from Ayrshire and other milk. In the last chapter two artificial neural networks were designed with the two starter organisms, Lactococcus lactis and Streptococcus thermophilus as variable indicator respectively. Thirty-two cheese samples of each batch (pure Ayrshire (4) / mix breed with no Ayrshire (4)) were ripened and samples were analysed under the same conditions on the following days after production: 2, 10, 22, 36, 50, 64, 78, and 92. In the subsequent chapters, the following analysis were done on each day of analysis: organic acid by means of high performance liquid chromatography (HPLC); fatty acids by means of Gas Chromatography Mass Spectometry (GCMS); amino acids by means of GC-MS; microbial analysis by means of traditional methods, total DNA extraction and polymerase chain reaction (PCR); and standard chemical analysis for moisture, NaCl and pH. In the first research chapter, the minimum and maximum (min/max) values, standard deviations and proposed rel X values of organic acids were evaluated in Ayrshire and the mixed-breed Cheddar cheese, and showed that isovaleric acid is the organic acid with the least variation relative to concentration in both cheeses and it was assumed that this organic acid is the most effective indicator of cheese uniformity. Clear differences in organic acids, chemical variables and starter micro-organisms were also evident in the two cheese batches. Results obtained from the regression models which was defined for each organic -; amino - and fatty acid by means of mathematical equations can be used by the manufacturer to achieve i.e. the selection of cheese for specialist lines, the early exclusion of defective cheeses, and the establishment of brand origin (Ayrshire vs. mixed-breed Cheddar cheeses). The regression graphs also illustrate unique flux patterns in Ayrshire and the mixed-breed in terms of organic -, fatty -, and amino acid content. In the last chapter, the discrimination between the two batches was respectively done via artificial neural network (ANN) modelling of Lactococcus lactis and Streptococcus thermophilus as indicator organisms. The ANN consisted of a multilayered network with supervised training arranged into an ordered hierarchy of layers, in which connections were allowed only between nodes in immediately adjacent layers. The construction thereof allowed for two output nodes, connected to an input layer consisting of two nodes to which the inputs were connected. In both cheeses the results from the ANN showed acceptable classification of the cheeses based on the counts of L. lactis and S. thermophilus.
45

Quality of life of chronic dialysis patients

Clark, Chevon Lee January 2013 (has links)
Thesis (D. Tech. (Clinical Technology)) -- Central University of technology, Free State, 2013 / Objectives: Survival with end stage kidney disease (ESKD) is made possible by dialysis but is in turn associated with increased morbidity, mortality, and decreased quality of life (QOL). Quality of life is a frequently overlooked, yet a critical consideration in evaluating the overall medical care of ESKD patients. This study aimed to evaluate the QOL of chronic haemodialysis (HD) and peritoneal dialysis (PD) patients in multiple dialysis units in South Africa. Methods: A comparative descriptive study carried out on 100 haemodialysis (HD) (n=100) and 100 peritoneal dialysis patients (PD) (n=100) patients, evaluating factors such as demographics, duration on dialysis, medical history, clinical indicators and the patient’s understanding thereof, was performed. Quality of life was measured using the medical outcomes study 36 (SF-36). These factors, clinical scores and QOL measures were compared amongst HD and PD patients and thereafter correlated to nephrology professionals’ perspective on QOL. Results: A total of 200 (n=200) patients from 11 dialysis units were evaluated. Mean age for the HD group was 49±15 years compared to 53±14 years for the PD group (p=0.043). The HD patient group had an improved physical composite (PCS) score adjusted for age, urea, creatinine and albumin (p<0.001). The mental composite score (MCS) was improved in the PD group although not significant (p>0.05). A positive correlation was found, as PD patients had an improved symptom control score, adjusted for age (p=0.04), an improved effect of kidney disease score adjusted for albumin (p=0.000), and an improved burden QOL score adjusted for urea, creatinine and albumin (p=0.019). Age was shown to be associated to the physical functioning (p=0.01) and PCS (p=0.040), and diabetes to the emotional role (p=0.04), in QOL. An increase in the years on dialysis showed a reduced emotional well-being (p=0.028) and being on the transplant list an improved MCS (p=0.003). Participation in a pre-end stage kidney disease (PESKD) management programme showed improvement in the general health component (p=0.032), the effect (p=0.01), and the burden of kidney disease (p=0.02). Assessing patients’ knowledge on ESKD revealed the relationship of the PCS to the understanding of managing the complications associated with CKD (p=0.01) and access management (p=0.01). The understanding of diet was found to be significant to the burden of CKD (p=0.01) and the complications associated with CKD was found to be further significant to the effect and symptom QOL (p=0.01). Nephrology professionals rated the difficulty of living with kidney disease a 7.49 out of 10 score and 71% felt QOL is taken into consideration with managing ESKD patients. Conclusion: The study demonstrated differences in the adjusted QOL scores amongst HD and PD dialysis patients in the dialysis units studied. The importance of PESKD was emphasized in relation to improved QOL. Quality of life is a valid marker and important for the ongoing audit of renal services.
46

The implementation of inclusive education in primary schools in the Lejweleputswa education district / by Teboho Godfrey Lebona

Lebona, Teboho Godfrey January 2013 (has links)
Thesis (M. Ed. ) - Central University of Technology, Free State, 2013 / The drafting and promulgation of education policies bring hope and an expectation to those whose interests, concerns and problems, are addressed by them. On the other hand, such policies bring confusion, uncertainty and stress to teachers who are expected to implement and put into practice prescripts of those policies. Response to the Education White Paper 6: Special Needs Education – Building an Inclusive Education and Training System (2001) and subsequent policies on inclusive education which followed, brought uncertainty to teachers and also led to some developing a negative attitude towards inclusive education. This study focused on the implementation of inclusive education in primary schools in the Lejweleputswa District of the Free State province. A literature review provided insight into the concept of inclusive education and moreover shed light on policy developments regarding learner diversity through the curriculum. An empirical investigation using a qualitative approach was conducted and data was gathered by means of focus group interviews with school-based support teams as well as a questionnaire completed by principals. Furthermore, the findings of the empirical investigation concurred, to a large degree, with the findings of the literature study. In general, it was brought to light that inclusive education is not implemented correctly in primary schools in the Lejweleputswa District. Based on certain findings, recommendations are made regarding the successful implementation of inclusive education in primary schools.
47

Geophagic practices and geophagic soil nematode content in Thabo Mofutsanyane District, South Africa

Perridge, Allison 12 1900 (has links)
Thesis (M. Tech.(Biomedical Technology)) - Central University of Technology, Free State, 2010 / Introduction: Geophagia, generally referred to as earth-eating, occurs in many countries of the world, including African countries such as South Africa. A need was identified to characterize human geophagic habits and the microbiological content of geophagic clayey soil, including the presence of potentially pathogenic nematodes (geohelminths), in South Africa. Materials and methods: Questionnaires were developed to generate data on human geophagia and included demography, socio-economics, indigenous knowledge, business aspects, mining and hygiene practices of vendors/geophagists. A total of 52 soil samples (n = 52) were collected from the district of Thabo Mofutsanyane (Free State, South Africa), which comprised of vendor, topsoil, excavated and control soil sample groups. Nematode content were isolated using the Ammonium bicarbonate protocol, thereafter the nematodes were classified and population sizes determined for each sample. Soil colour classification was completed using the Munsell Soil Color Charts. Results and discussion: The questionnaire revealed that geophagia in this region was practised mainly by women of child-bearing age because of the taste of the soil. Vendors sell geophagic clayey soil (known as mobu) collected from the mountain- and riversides for subsistence, generally costing one to two rand per bag. Hygiene and environmental conditions are considered when mining geophagic clayey soils. Whitish-perceived clayey soils are preferred by most of the geophagists. According to the Munsell Soil Color classification, Thabo Mofutsanyane geophagic soils ranged from brownish, to greyish, to yellowish in colour. Vendor soils were mostly greyish, while topsoils, excavated soils and control soils were mostly brownish. No human pathogenic nematode ova or larvae were isolated from any of the samples, however 34 nonpathogenic nematode taxa representing five trophic levels were identified. These included mainly herbivores, but also fungivores, bacteriovores, omnivores and predators. Taxon richness (number of taxa) greatly varied in the soil sample groups with vendor soil n = 9, topsoil n = 24, excavated soil n = 16 and control soil n = 14. Tylenchus sp., Criconemoides sphaerocephalus and Ditylenchus sp. were the only nematode taxa identified in all the different sample groups, with Tylenchus sp. notably more abundant overall. When the median nematode population sizes were compared between the geophagic soil samples, no significant difference (p ≥ 0.05) could be identified. In contrast, the median nematode population sizes for all samples differed significantly (p < 0.05) from the control soil sample group. Conclusion: This study revealed that geophagia is probably not a vector for geohelminth infection in the district of Thabo Mofutsanyane, South Africa. However, the rich presence of non-pathogenic soil nematode communities in these brownish, greyish and yellowish geophagic soils may be useful as biological indicators of general soil health.
48

"Research education" : a concept wider than postgraduate supervision?

Lategan, L.O.K. January 2014 (has links)
Published Article / This paper promotes the argument that although conventional postgraduate supervision is useful to address the research skills and competences of postgraduate students, a wider perspective is nonetheless required to educate and train any researcher (including postgraduate students upon their entrée into the world of research) to comprehend the demands made by research and how best these demands can be addressed. It is in this context that a more comprehensive concept of research education is promoted. The argument is based on the perspective that methodological understanding alone is not sufficient to assist a researcher in meeting the expectations of a research project. Research education refers to the training of researchers to be responsive to the research value chain. This includes aspects such as the formal research process, the importance of research ethics and integrity regarding the research project, the imperative to promote scholarship in research and the application of research results through technology transfer, innovation and incubation. Research education sensitizes the researcher to look beyond the scope of the academic research project and to extend the research to activities such as technology transfer, innovation, commercialization and partnerships. The aim of research education is to promote the wide range of aspects contributing to the understanding of what counts as research and its application.
49

Treatment and disposal of medical waste in rural and urban clinics within Polokwane municipality of South Africa

Raphela, S.F. January 2014 (has links)
Published Article / The objective of the study was to assess the medical waste management practices used by clinics located in the Polokwane Municipality, South Africa. The clinic personnel were not informed prior to the visit. A walkthrough survey was conducted on-site where potential health and safety risks were identified and noted. The health care personnel in charge of specific clinics completed the questionnaires providing general and detailed information about the treatment and disposal of medical waste. Frequencies and percentages were calculated from the data obtained. Data obtained indicate that (i) medical waste was not segregated from general waste in most of the clinics, (ii) rural clinics were burning medical waste with general waste inside the clinic yard (iii) there was no sufficient collection and transport of medical waste in clinics, (iv) sharps were disposed at various hospital incinerators and (v) most of the clinics did not have storage facilities for medical waste.
50

Student perspectives on the adoption of a blended learning model for the Tshwane University of Technology

Mosiane, Kim Kagiso. January 2015 (has links)
M. Tech. Business Administration / The study was conducted at Tshwane University of Technology (TUT) Business School in order to assess the degree of interest in the blended method of teaching and learning among Business School students. The study was based on a sample of size 50 students who were enrolled as Year III students while the study was being conducted at the Business School. Data was collected by using a structured, pre-tested and validated questionnaire of study from each of the 50 students who took part in the study. Data analyses were performed by using methods such as frequency tables, Fisher’s exact tests of associations and Marcov Chain Monte Carlo (MCMC) algorithms or Bayesian analysis.

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