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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

A curriculum framework for continuing professional development in culinary studies

Jooste, Susina M. 12 1900 (has links)
Thesis (MEd (Curriculum Studies)--University of Stellenbosch, 2007. / Culinary studies is a relatively young and unfamiliar field of study which engages the application of life and natural sciences, business and technology in a food-specific environment. The growth in the demand for training, re-training and continuing professional development in the culinary arts can be attributed to factors such as enhanced culinary programmes at high school level, an increased level of education and expectation about food in general, growth in culinary tourism and highly polished food magazines or other publications. The celebrity status of high-profile chefs and a stronger economy that enables more people to explore fine dining and gourmet food can be added to the list of factors that influence the interest in culinary arts as a profession. The number of qualified culinary professionals has increased over the last 10 years in South Africa, providing a large corps of people with a good understanding of this field of study and a need for continuing professional development opportunities. This study was a response to the challenges of the demand for continuing professional development opportunities from this growing body of culinary professionals. The demand for continuing professional development opportunities in culinary studies is becoming more complex and challenging for both learner and teacher. Although institutions that provide training in hospitality are also in the business of culinary education, their perspectives and focus are quite diverse. Culinary education can therefore be improved through a deeper understanding of the curriculum development process combined with the expectations of both the industry and the individual. A fundamental shortcoming in the field of culinary education is often that persons with limited expertise in the field of curriculum studies bear the primary responsibility for addressing curriculum challenges. The development of curricula for professional development in culinary studies subsequently happens at the expense of understanding the curriculum. The primary aim therefore of this study was to identify and propose a curriculum framework for continuing professional development in culinary arts. This framework might contribute to providing a curriculum foundation, credibility to the broad hospitality industry and specifically to culinary studies, as well as to the securing of some uniformity of standards over the spectrum of culinary qualifications. A scientifically validated situational analysis was executed by means of focus group discussions, personal interviews, curriculum comparisons and an electronic mail questionnaire survey, which mainly generated qualitative data. These techniques were used in triangulation as research instruments to investigate the needs for continuing professional development in culinary arts and the availability of curricula to address these needs. The greatest challenges in culinary studies were reflected in the complexity and multidisciplinary nature of this relatively undefined industry and field of study. The intricate relation, interaction, collaboration and contexts between secondary schools, various culinary training institutions, industry and culinary professionals were investigated. The data generated confirmed the need for training and development opportunities to improve the professional status of culinary professionals in South Africa The promotion of a change in direction for culinary studies development in South Africa could ensure future growth as a discipline cognitively and professionally, in line with international standards, procedures and practices. The range of challenges and changes facing the industry varies from social issues to the educational issues of qualifications and credible accreditations, which are addressed in the proposed curriculum framework. The lack of more empirical research in this field of study is an indication that both students and professionals should be encouraged to do the relevant research and that higher education institutions should provide the opportunities and structures for such research.
42

Application of multivariate regression techniques to paint: for the quantitive FTIR spectroscopic analysis of polymeric components

Phala, Adeela Colyne January 2011 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology Chemistry in the Faculty of (Science) Supervisor: Professor T.N. van der Walt Bellville campus Date submitted: October 2011 / It is important to quantify polymeric components in a coating because they greatly influence the performance of a coating. The difficulty associated with analysis of polymers by Fourier transform infrared (FTIR) analysis’s is that colinearities arise from similar or overlapping spectral features. A quantitative FTIR method with attenuated total reflectance coupled to multivariate/ chemometric analysis is presented. It allows for simultaneous quantification of 3 polymeric components; a rheology modifier, organic opacifier and styrene acrylic binder, with no prior extraction or separation from the paint. The factor based methods partial least squares (PLS) and principle component regression (PCR) permit colinearities by decomposing the spectral data into smaller matrices with principle scores and loading vectors. For model building spectral information from calibrators and validation samples at different analysis regions were incorporated. PCR and PLS were used to inspect the variation within the sample set. The PLS algorithms were found to predict the polymeric components the best. The concentrations of the polymeric components in a coating were predicted with the calibration model. Three PLS models each with different analysis regions yielded a coefficient of correlation R2 close to 1 for each of the components. The root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) was less than 5%. The best out-put was obtained where spectral features of water was included (Trial 3). The prediction residual values for the three models ranged from 2 to -2 and 10 to -10. The method allows paint samples to be analysed in pure form and opens many opportunities for other coating components to be analysed in the same way.
43

Use of food-buying practices within different socio-economic classes in the city of Cape Town

Harper, Crystal January 2013 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology Consumer Science: Food and Nutrition in the Faculty of Applied Sciences at the Cape Peninsula University of Technology 2013 / Consumer debt has escalated in South Africa ever since the country sank into a recession in early 2009. One of the many consequences of this economic downturn has been a major increase in energy, transport and food prices. Food-buying strategies can be used by consumers to help to reduce the amount of money, which is spent on food, and increase funds that are available for other household expenses. The main objective of this study was to determine the use of four pre-selected food-buying practices by consumers who reside in different socio-economic status (SES) areas in the City of Cape Town. Residents of lower SES areas have been found to have purchasing patterns that are different to those who live in higher SES areas. The subsidiary objectives were to further establish whether there is a difference in the use of food-buying practices by consumers who reside in different SES areas, and to ascertain whether shopper and demographical characteristics have an influence on the use of food-buying practices among consumers in general as well as among consumers within the same SES area. A consumer intercept survey was conducted after being granted ethics approval. Three groups of respondents that represent a low, middle and high SES area were systematically sampled. A total of 1 200 consumers (95% response rate) who are older than 18 years anonymously and voluntarily participated in the study, which was conducted at pre-selected stores in the suburban areas of Delft (low SES area), Maitland (middle SES area) and Meadowridge (high SES area) in the City of Cape Town. These areas and stores were selected to represent the SES of households or consumers, respectively, based on the demographic and employment profile that was provided for each by Statistics South Africa‟s 2001‟s census profiles. The data was collected by using a pilot tested structured, self-administered questionnaire consisting of mainly multiple-choice questions, which gathered information from the respondents regarding their shopper and demographic characteristics, as well as their frequency of use of the four food-buying practices (represented by six structured questions each) as: (i) use of a shopping list; (ii) use of advertisements to plan shopping; (iii) comparison of prices amongst different brands; and (iv) avoidance of impulse buying. These food-buying practices were selected based on available consumer education literature, which focused on the use of these food-buying practices and a pilot study that was conducted in 2011, which indicated that these four practices were most frequently used by the consumers who were surveyed. Within each SES area most of the Cronbach‟s alpha coefficients that were obtained were >0.9 among the six questions, which represented each food-buying practice, and reflected strong internal consistencies among the questions. The Generalised Linear Model analysis of variance utilising the Wald statistic, which is based on the chi- square distribution and Bonferroni pair-wise comparisons, were used to determine significant differences between respondents‟ use of the food-buying practices and their SES area group, as well as their shopper and demographic characteristics. A significant level of p<0.001, as well as p<0.05 was used. Most (60 to 80%) of the respondents in each SES area are female. Within the total sample, low and middle SES areas a majority (62 to 73%) of the respondents were between 26 to 55 years of age, whereas in the high SES area a majority (63.5%) of the respondents were 46 years and older. In general, more than half (52 to 56%) of the respondents were married and most (38 to 55%) were employed full-time and had household sizes, which mainly (18 to 23%) consist of two to four members. Regarding highest level of education attained, most of the respondents in the total sample either had a Grade 8 to 11 (37.6%) or a Grade 12 (24.7%), whereas most (54%) respondents in the high SES had either acquired a post-matric diploma or certificate, degree or post-graduate degree. Most (67 to 89 %) of the respondents within the total sample, middle and low SES area associated themselves with the Coloured population group, whereas most (56.7%) of the respondents in the high SES area associated themselves with the White population group. Concerning household monthly income, two thirds (65%) of the respondents within the high SES area had an income of R12 801 upward; most (77.5%) of the respondents within the middle SES area had an income of R801 to R12 800 per month; and more than half (57%) of the respondents in the low SES area received an income of R800 to R3 200 per month. In general, most respondents indicated that they shopped for food once a week (33 to 48%); took less than half an hour to shop for food (40 to 52%); and usually shopped alone for food (68.9%). Cash was the most prevalent means of payment among respondents within the total sample (66.7%), middle (70.5%) and low (93%) SES areas, while most (43.2%) respondents in the high SES area paid by means of a debit card. Among the respondents who reside in the different SES suburban areas, differences in the use of food-buying practices were revealed. Respondents within the high (p<0.001) and middle (p<0.05) SES areas displayed a higher propensity to use a shopping list, yet a lower propensity to use advertisements compared to respondents within the low SES area. Respondents within the low and particularly middle SES area displayed a higher propensity to compare prices (p<0.05) compared to respondents within the high SES area. No differences (p>0.05) for the avoidance of impulse buying as a food-buying practice were found among respondents within a low, middle and high SES area. A largely low propensity to avoid impulse buying was found. Regarding shopper characteristics, the respondent payment method influenced the use of a shopping list (p<0.05), use of advertisements (p<0.05 and p<0.001 between the payment methods) and propensity to avoid impulse buying (p<0.05) as food-buying practices within the low SES area. Among respondents, in general, the payment method influenced the avoidance of impulse buying (p<0.05) as a food-buying practice. The length of time that it took to shop influenced the use of a shopping list (p<0.05) as a food-buying practice within the low SES area and the propensity to compare prices of different brands (p<0.05) as a food-buying practice within the middle SES area. Shopping frequency influenced the use of advertisements (p<0.05) as a food buying practice within the low SES area and co-shopping influenced the propensity to avoid impulse buying (p<0.05 and p<0.001 between the various co-shoppers) as a food-buying practice within the low SES area, as well as the propensity to use advertisements (p<0.05) as a food-buying practice within the high SES area. Gender influenced the use of a shopping list (p<0.05) as a food-buying practice within the high SES area and the use of advertisements (p<0.05), as well as the propensity to avoid impulse buying (p<0.001) as food-buying practices within the middle SES area. Gender also affected the propensity to compare the prices of different brands (p<0.05) as a food-buying practice within the low SES area and among respondents, in general, the propensity to avoid impulse buying (p<0.05), as well as the use of advertisements (p<0.001) as food-buying practices. Employment status affected the use of a shopping list (p<0.05) as a food-buying practice within the high SES area. Population group affected the propensity to use advertisements as a food-buying practice within the low SES area (p<0.05 and p<0.001 between the population groups) and among the respondents, in general, (p<0.05). Household monthly income affected the propensity to compare the prices of different brands (p<0.05) as a food-buying practice within the high SES area. Among the respondents, in general, household monthly income affected the propensity to compare the prices of different brands (p<0.05 and p<0.001 between the income groups) and the use of advertisements (p<0.05) as food-buying practices. The study confirmed that there are differences in the use of food-buying practices among consumers who reside in different SES areas, and further identified specific shopper and demographic characteristics that have an effect on consumers‟ (in general, as well as within the same SES area) use of food-buying practices. Since food-buying practices can be used by consumers to manage their household income expenditure on food, consumer awareness of these practices, in particular the avoidance of impulse buying should be promoted through educational efforts ideally by food retail companies. These companies have the resources and capability to communicate with consumers regularly (while shopping in-store), and can inform their customers about food-buying practices that would help them to save money and/or make additional funds available for other essential household expenses.
44

In vitro propagation of Agathosma betulina an indigenous plant of economic importance

Witbooi, Hildegard January 2013 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Horticultural Sciences in the Faculty of Applied Sciences at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY Supervisor: Dr L Kambizi Co-supervisor: Dr NP Makunga Cape Town December 2013 / Agathosma betulina (Berg.) Pillans, previously known as Barosma betulina, is a member of the Rutaceae family, and indigenous to the fynbos botanical biome of the Western Cape of South Africa. It is commonly known as buchu. Extracts as well as powdered leaves have traditionally been used for the treatment of various ailments. The increase in the international demand for A. betulina for health as well as food and beverage benefits, have raised concerns over exploitation of wild populations and the lack of horticultural information necessitates this study to evaluate the propagation of this economical important species. The main objective of this study was to establish a simple and highly productive micropropagation protocol for A. betulina through experimenting with nodal explants. Testing of the effect of various treatments (physical scarification, chemical scarification, GA, stratification, smoke and combinations thereof) on the in vitro germination of A. betulina seeds was done to elucidate the factors which control seed germination. The study revealed that the physical scarification and smoke-induced germination had a significant effect on germination percentages. In terms of germination rate, the radical generally started to appear after approximately 10 days in the physical scarification with smoke treatment. Initial decontamination methods with the exposure of various concentrations of NaOCl gave fatal results, however 1.5% NaOCl had more phenolic reactions rather than fungal or bacterial contamination. Interestingly, contamination rates of explants were influenced by the stage of maturity of the explant material. This plant material was used to test different strengths of regeneration media, to ensure that the explants receive ample nutrients. Results made exhibited that ½ MS was the best strength for growing A. betulina nodal explants. Compared comparison between in vitro derived explants and ex vitro collected explants showed that the ex vitro derived explants had significant results, but the explants lost vigour soon after the initial exponential growth leading to the explants dying off. Furthermore, ex vitro decontaminated plant material was not economically viable to continue with. Seedlings derived from germinated seeds appeared to be the preferred method of propagation as this spent the least time in culture and produced a stable plant with an established root system, which is essential during the hardening off process after in vitro growth. When exposing nodal explants to phytohormone 2,4-D it responds best to dosages 0.5mg Lˉ¹ and 1mg Lˉ¹. Phytohormone BA was very effective in producing soft friable callus. The best results were shown when 0.5mg Lˉ¹ BA was applied to ½ MS media. For both shoot length and multiple shoot production, a combination of phytohormones BA-NAA (1: 0.5mgLˉ¹) had the most significant results. Interestingly, a higher phytohormone concentration of NAA is necessary to develop multiple adventitious roots. The effect of 3mg Lˉ¹ was significant in that it resulted in multiple adventitious roots, but fewer calli was observed in this treatment. Micropropagation becomes valuable as little attention between subcultures is needed; making it less labour intensive compared to conventional nursery propagation systems where weeding watering and spraying of plants are labour intensive. In the traditional world of medicine, more so in Southern Africa, extracts are prepared by adding boiling water to the plant material; however commercial ethanol is used as an extractant. Establishment of the essential oil quality of the in vitro cultures post exposure to various treatments was done. Analysis of essential oils from A. betulina resulted in the identification of twenty one compounds. The results showed qualitative as well as quantitative differences amongst the samples used in the study. The highest relative concentration of limonene was observed in the callus of nodal explants after it was exposed to 0.5mg lˉ¹ NAA. No pulegone was found in this treatment making it ideal for limonene production. This suggests that liquid culture with the same treatment may produce more calli making it ideal for the production of limonene.
45

Evaluating an information literacy intervention for first year engineering students at the Cape Peninsula University of Technology

Marion Davids January 2009 (has links)
<p>The aim of the research project is to investigate the effectiveness of an information literacy intervention for first year engineering students at the Cape Peninsula University of Technology. Information literacy has been identified as a necessary outcome of tertiary education. It refers to the life-long learning competencies of finding and using information in order to solve problems, to make decisions and to create new knowledge. Information literacy education has evolved from earlier forms of library user education, such as bibliographic instruction, and is central to the mission of academic libraries. However, librarians responsible for information literacy programmes seldom evaluate the effectiveness of their interventions. In today&rsquo / s climate of accountability and outcomes-based education, it is necessary to provide evidence of the benefits of the user education that libraries provide. The researcher uses the American College and Research Library (ACRL) Information Literacy Competency Standards for Higher Education, which are internationally recognized and widely used by South African academic librarians, as a benchmark to evaluate an intervention for a group of first year students enrolled for a mechanical engineering course. The intervention consists of two workshops which aim to teach the students to find information relevant to their essays via the university&rsquo / s OPAC, various engineering databases and to teach them how to reference and cite their sources in their essays. The research methodology assessed students&rsquo / information literacy before and after the two workshops with the use of a questionnaire consisting of a set of questions based on some of the ACRL standards. The questionnaire also gathered data on students&rsquo / prior experience of libraries, reading and computers, which might impact on their information literacy...</p>
46

Evaluating an information literacy intervention for first year engineering students at the Cape Peninsula University of Technology

Marion Davids January 2009 (has links)
<p>The aim of the research project is to investigate the effectiveness of an information literacy intervention for first year engineering students at the Cape Peninsula University of Technology. Information literacy has been identified as a necessary outcome of tertiary education. It refers to the life-long learning competencies of finding and using information in order to solve problems, to make decisions and to create new knowledge. Information literacy education has evolved from earlier forms of library user education, such as bibliographic instruction, and is central to the mission of academic libraries. However, librarians responsible for information literacy programmes seldom evaluate the effectiveness of their interventions. In today&rsquo / s climate of accountability and outcomes-based education, it is necessary to provide evidence of the benefits of the user education that libraries provide. The researcher uses the American College and Research Library (ACRL) Information Literacy Competency Standards for Higher Education, which are internationally recognized and widely used by South African academic librarians, as a benchmark to evaluate an intervention for a group of first year students enrolled for a mechanical engineering course. The intervention consists of two workshops which aim to teach the students to find information relevant to their essays via the university&rsquo / s OPAC, various engineering databases and to teach them how to reference and cite their sources in their essays. The research methodology assessed students&rsquo / information literacy before and after the two workshops with the use of a questionnaire consisting of a set of questions based on some of the ACRL standards. The questionnaire also gathered data on students&rsquo / prior experience of libraries, reading and computers, which might impact on their information literacy...</p>
47

Performance of a symmetrical converging-diverging tube differential pressure flow meter

Ilunga, Luc Mwamba January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Civil Engineering in the Faculty of Engineering at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2014 / The current problems of orifice, nozzle and Venturi flow meters are that they are limited to turbulent flow and the permanent pressure drop produced in the pipeline. To improve these inadequacies, converging-diverging (C-D) tubes were manufactured, consisting of symmetrical converging and diverging cones, where the throat is the annular section between the two cones, with various angles and diameter ratios to improve the permanent pressure loss and flow measurement range. The objective of this study was firstly to evaluate the permanent pressure loss, secondly to determine the discharge coefficient values for various C-D tubes and compare them with the existing differential pressure flow meter using Newtonian and non-Newtonian fluids, and finally to assess the performance of these differential pressure flow meters. The tests were conducted on the multipurpose test rig in the slurry laboratory at the Cape Peninsula University of Technology. Newtonian and non-Newtonian fluids were used to conduct experiments in five different C-D tube flow meters with diameter ratios (β) of 0.5, 0.6 and 0.7, and with angles of the wall to the axis of the tube (θ) of 15°, 30° and 45°. The results for each test are presented firstly in the form of static pressure at different flow rates. It was observed that the permanent pressure loss decreases with the flow rate and the length of the C-D tube. Secondly, the results are presented in terms of discharge coefficient versus Reynolds number. It was found that the Cd values at 15° drop earlier than at 30° and 45°; when viscous forces become predominant, the Cd increases with increasing beta ratio. The Cd was found to be independent of the Reynolds number for Re>2000 and also a function of angle and beta ratio. Preamble Performance of a symmetrical converging-diverging tube differential pressure flow meter Finally, the error analyses of discharge coefficients were assessed to determine the performance criteria. The standard variation was found to increase when the Reynolds number decreases. The average discharge coefficient values and their uncertainties were determined to select the most promising C-D tube geometry. An average Cd of 0.96, with an uncertainty of ±0.5 % for a range of Reynolds numbers greater than 2,000 was found. The comparison between C-D tubes 0.6(15-15) and classical Venturi flow meters reveals that C-D 0.6(15-15) performs well in turbulent range and shows only a slight inaccuracy in laminar. This thesis provides a simple geometrical differential pressure flow meter with a constant Cd value over a Reynolds number range of 2000 to 150 000.
48

A performance study of a voltage-fed reluctance synchronous machine

Smith, Robert Albert January 2013 (has links)
Submitted to the Department of Electrical Engineering in Fulfilment of the Requirements for the Magister Technologiae in Electrical Engineering at the Cape Peninsula University of Technology SUPERVISOR: E. VOSS NOVEMBER 2013 / The reluctance synchronous machine (RSM) operates on the principle of magnetic reluctance, which is produced through a careful selection of rotor flux barriers and cut-outs. Magnetic reluctivity is the resistance to magnetic flux and can be directly related to the principles of Ohm’s law in electrical circuits. Although reluctance motors have been known for more than 150 years, researchers lost interest when Nikola Tesla’s induction machine (IM) was introduced to industry. Over the last few decades, however, RSMs have shown a lot of potential. They are cheap, robust, reliable, and their rotors can also be used in the stators of IMs. The disadvantage of these machines is an inherently high torque ripple, being the result of its rotor geometry, but the biggest advantage is having a significant reduction in copper losses after the rotor cage has been removed. This advantage drove engineers to investigate, optimise and modify the performance and structure of this machine, which led to the usage of electronic drive systems. The recent advances in technology have allowed researchers to further investigate and modify the design and performance of this special type of machine, with the integration of Finite Element Analysis (FEA) software also making a contribution to the development of the RSM’s current driven systems. The voltage-fed RSM, driven direct-on-line (DOL) from the utility supply, was left in the shadows as the current-fed RSM took reign, but still is, in the author’s opinion, not yet fully analysed. This thesis practically investigates the performance characteristics of the cageless, voltage-fed 3kW RSM in its steady-state operation, under various loads. These performance characteristics are also compared to a RSM driven from a sensorless vector drive (current-fed) to investigate the advantages and disadvantages between the two. Experiments performed on the test bench immediately reveal a limitation to the voltage-fed RSM’s ability to drive higher loads. While the current-fed RSM conveniently reaches 150% of its full-load, the voltage-fed RSM, due to its cageless structure, only reaches 110% of its full-load power. Despite this discovery, the voltage-fed RSM proves to have a lower core loss, harmonic content and torque ripple. Using a FE software package with an integrated source-code, additional parameters such as the dq-axis inductances and currents are also compared and analysed in terms of its reaction to an increase in load. The eddy-current, hysteresis and excess losses are also analysed as well as the harmonic components caused by the geometry of the RSM. For academic purposes, a fair amount of emphasis is placed on the approach to the problem. The preparation for the FE simulation is explained in detail, providing insight into the FE mathematical model as well as parameter acquisition. These parameters include current angle, friction and windage losses, stator resistance, end-winding leakage reactance, core loss and inertia. The results obtained by the FE model are compared to that of the measured results and is found to have an error of only 0.52%. Furthermore, this study attempts to find the feasibility of the voltage-fed RSM’s practicality in modern-day industry. The conclusion is drawn that the voltage-fed RSM could be used as a more elegant alternative to an otherwise over-complicated and over-priced installation.
49

A practical investigation into the measurement of forces on the stator teeth of electrical machines

Bevan, Graeme Rhys January 2013 (has links)
Submitted to the Department of Electrical Engineering in Fulfilment of the Requirements for the Magister Technologiae in Electrical Engineering at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY SUPERVISOR: E. VOSS NOVEMBER 2013 / Radial and peripheral displacement of stator teeth in electrical machines is known to be the cause of undesired vibration which leads to noise. This thesis serves to investigate the possibility of physically measuring the radial displacement of stator teeth caused by electromagnetic forces which, to the author’s knowledge, has not yet been achieved. A simplified practical approach is adopted in order to address the inherent difficulties attached to this problem, and the measurement of displacement is done by means of an experimental rig where a tooth is subjected to magnetic force acting over an air gap. Three experiments are carried out, each comprising ten tests, the results of which are compared in order to gain some idea as to the magnitudes of displacement which can be expected over a range of applied air gap flux densities. The aim of this work is to observe the displacement response of magnetised EM core material when acted upon by forces, and to see if the measured results agree with the elastic displacement predicted by a wellknown formula. It will be shown that although the measured results are in the same range as the predicted results, there is a deviation from the predicted linearity due to certain characteristics of the force rig, which are explained. The chosen measurement method is capacitive displacement and is shown to be a viable alternative to the more commonly used search coils and vibrometers in past literatures, especially when measuring displacements on the nano-scale. In addition, this study shows the importance of using 3D finite element software to simulate the electromagnetic model when saturation is present in the core of the test specimen. The important findings of this work are discussed in detail, and some ideas put forward, in an attempt to establish a starting point for future related work in the measurement of electromagnetic forceinduced displacement of stator teeth in electrical machines.
50

Development of methods for distribution network power quality variation monitoring

Nduku, Nyaniso Prudent January 2009 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009 / The purpose of this project is to develop methods for distribution network power quality' variations monitoring. Power quality (PO) has become a significant issue for both power suppliers and customers. There have been important changes in power system regarding to power quality requirements. "Power quality" is the combination at voltage quality and current quality. The main research problem of the project is to investigate the power quality of a distribution network by selection of proper measurement, applying and developing the existing classic and modern signal conditioning methods for power disturbance's parameters extracting and monitoring. The research objectives are: To study the standard lEC 61000-4-30 requirements. to investigate the common couplings in the distribution network. To identity the points for measurement, to develop MySQL database for the data from the measurement and to develop MATLAB software tor simulation of the network To develop methods based on Fourier transforms for estimation of the parameters of the disturbances. To develop software for the methods implementation, The influence of different loads on power quality disturbances are considered in the distribution network. Points on the network and meters according to the lEC power quality standards are investigated and applied for the CPUT Bellville campus distribution network. The implementation of the power quality monitoring for the CPUT Bellville campus helps the quality of power supply to be improved and the used power to be reduced. MATLAB programs to communicate with the database and calculate the disturbances and power quality parameters are developed.

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