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Validation of high frequency propagation prediction models over Africa

- Tshisaphungo, Mpho

  • Authors: Tshisaphungo, Mpho
  • Date: 2010
  • Subjects: Ionospheric radio wave propagation , Ionospheric radio wave propagation -- Forecasting , Radio meteorology , Radio wave propagation -- Africa , Ionosphere -- Africa -- Radio waves , Atmospheric physics -- Africa , Shortwave radio -- Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5553 , http://hdl.handle.net/10962/d1015239
  • Description: The ionosphere is an important factor in high frequency (HF) radio propagation providing an opportunity to study ionospheric variability as well as the space weather conditions under which HF communication can take place. This thesis presents the validation of HF propagation conditions for the Ionospheric Communication Enhanced Profile Analysis and Circuit (ICEPAC) and Advanced Stand Alone Prediction System (ASAPS) models over Africa by comparing predictions with the measured data obtained from the International Beacon Project (IBP). Since these models were not developed using information on the African region, a more accurate HF propagation prediction tool is required. Two IBP transmitter stations are considered, Ruaraka, Kenya (1.24°S, 36.88°E) and Pretoria, South Africa (25.45°S, 28.10°E) with one beacon receiver station located in Hermanus, South Africa (34.27°S, 19.l2°E). The potential of these models in terms of HF propagation conditions is illustrated. An attempt to draw conclusions for future improvement of the models is also presented. Results show a low prediction accuracy for both ICEPAC and ASAPS models, although ICEPAC provided more accurate predictions for daily HF propagation conditions. This thesis suggests that the development of a new HF propagation prediction tool for the African region or the modification of one of the existing models to accommodate the African region, taking into account the importance of the African ionospheric region, should be considered as an option to ensure more accurate HF Propagation predictions over this region.
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  • Date Issued: 2010

Veldram performance testing of dorper rams in Namibia : performance testing, progency testing and factors influencing sale price of rams

- Grobler, Hermanus Johannes Fourie

  • Authors: Grobler, Hermanus Johannes Fourie
  • Date: 2010
  • Subjects: Dorper sheep -- Breeding -- Namibia , Sheep -- Breeding -- Namibia , Dorper sheep , Sheep breeds
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10733 , http://hdl.handle.net/10948/1545 , Dorper sheep -- Breeding -- Namibia , Sheep -- Breeding -- Namibia , Dorper sheep , Sheep breeds
  • Description: The study aims to determine the contribution made by available ram growth- and breed standard parameters on the sale price of auctioned rams in Namibia. These findings serve as an indication of the importance ram buyers place on individual parameters in selecting rams for breeding purposes. It furthermore tries to establish whether scientific measurement for the estimation of ram breeding values takes precedence over subjective appraisal. The analysis of the 100 day and 270 day growth performance of the progeny of selected Veldram tested rams were used to evaluate the accuracy of the estimation of ram breeding values and may serve to validate the proper execution of these Veldram tests.
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  • Date Issued: 2010

Viability study of an ethnic cosmetic retailer in Port Elizabeth

- Rose, Grant

  • Authors: Rose, Grant
  • Date: 2010
  • Subjects: Cosmetics industry -- South Africa -- Port Elizabeth , Ethnic groups -- Health and hygiene -- South Africa , Market surveys -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8603 , http://hdl.handle.net/10948/1625 , Cosmetics industry -- South Africa -- Port Elizabeth , Ethnic groups -- Health and hygiene -- South Africa , Market surveys -- South Africa -- Port Elizabeth
  • Description: The primary objective of this study is to determine the viability of opening a speciality top end, Ethnic cosmetic and toiletry retailer in the Greenacres Mall of Port Elizabeth, in order to meet the cosmetic and toiletry needs of Ethnic consumers, having moved from rural places of work and dwelling, to urban areas of work and dwelling. In order to achieve the above mentioned primary objective, the following secondary objectives will be pursued: • To investigate the current and forecast Ethnic cosmetic and toiletry trends in the United States of America, in order to serve as a benchmark in the development of a top end, speciality Ethnic cosmetic and toiletry retail store model, for the Greenacres Shopping Mall in Port Elizabeth, South Africa; • to identify whether a top end, speciality Ethnic cosmetic and toiletry store model for the Greenacres Shopping Mall in Port Elizabeth, South Africa, would be a viable business venture; • to investigate current and forecast Ethnic cosmetic and toiletry trends in South Africa, in order to reveal the shortfalls of retailers targeting this market segment; and • to identify the best business model for an organisation or individual wanting to grow their business through targeting the Ethnic cosmetic and toiletry consumer
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  • Date Issued: 2010

Visual based finger interactions for mobile phones

- Kerr, Simon

  • Authors: Kerr, Simon
  • Date: 2010 , 2010-03-15
  • Subjects: User interfaces (Computer systems) , Mobile communication systems -- Design and construction , Cell phones -- Software , Mobile communication systems -- Technological innovations , Information display systems , Cell phones -- Technological innovations
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4652 , http://hdl.handle.net/10962/d1006621 , User interfaces (Computer systems) , Mobile communication systems -- Design and construction , Cell phones -- Software , Mobile communication systems -- Technological innovations , Information display systems , Cell phones -- Technological innovations
  • Description: Vision based technology such as motion detection has long been limited to the domain of powerful processor intensive systems such as desktop PCs and specialist hardware solutions. With the advent of much faster mobile phone processors and memory, a plethora of feature rich software and hardware is being deployed onto the mobile platform, most notably onto high powered devices called smart phones. Interaction interfaces such as touchscreens allow for improved usability but obscure the phone’s screen. Since the majority of smart phones are equipped with cameras, it has become feasible to combine their powerful processors, large memory capacity and the camera to support new ways of interacting with the phone which do not obscure the screen. However, it is not clear whether or not these processor intensive visual interactions can in fact be run at an acceptable speed on current mobile handsets or whether they will offer the user a better experience than the current number pad and direction keys present on the majority of mobile phones. A vision based finger interaction technique is proposed which uses the back of device camera to track the user’s finger. This allows the user to interact with the mobile phone with mouse based movements, gestures and steering based interactions. A simple colour thresholding algorithm was implemented in Java, Python and C++. Various benchmarks and tests conducted on a Nokia N95 smart phone revealed that on current hardware and with current programming environments only native C++ yields results plausible for real time interactions (a key requirement for vision based interactions). It is also shown that different lighting levels and background environments affects the accuracy of the system with background and finger contrast playing a large role. Finally a user study was conducted to ascertain the overall user’s satisfaction between keypad interactions and the finger interaction techniques concluding that the new finger interaction technique is well suited to steering based interactions and in time, mouse style movements. Simple navigation is better suited to the directional keypad.
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  • Date Issued: 2010

Volatility and the risk return relationship on the South African equity market

- Mandimika, Neville

  • Authors: Mandimika, Neville
  • Date: 2010
  • Subjects: Stock exchanges , Financial risk -- South Africa , Saving and investment -- South Africa
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1009 , http://hdl.handle.net/10962/d1002744 , Stock exchanges , Financial risk -- South Africa , Saving and investment -- South Africa
  • Description: The volatility of stock markets has important implications for investment decision making, financial stability and overall macroeconomic stability. This study examines the risk-return relationship as well as the behaviour of volatility of the South African equity markets using both aggregate, industrial level and sector level data. The study is divided into three parts. The first part investigates the behaviour of volatility in each of the industries, sectors and the benchmark series focussing on whether volatility is symmetric or asymmetric. Subsequently we investigate which, among the GARCH family of models appropriately captured the riskreturn relationship under which distributional assumption. The second part examines the riskreturn relationship on the SA stock market. The third part examines the long term trend of volatility and whether volatility significantly increases during financial crises and during major global shocks. The GARCH-M, EGARCH-M and TARCH-M models under the Gaussian, Student –t and the GED are used. The findings this study makes are as follows: firstly, there is no clear relationship between risk and return. Secondly, volatility is asymmetrical, implying that bad news has a greater effect on volatility than good news in the South African equity market. Thirdly, the TARCH-M model under the GED was found to be the most appropriate model. Fourthly, volatility increases during financial crises and major global shocks. Overall, volatility is generally not priced on the South African equity markets. Thus, both local and international investors need to consider other factors that influence returns such as skewness. The general increase in volatility during financial crises and major global shocks poses a major concern for policy makers as this may cause financial instability. Thus policy makers need to be mindful of the behaviour of volatility in the South African equity market in response to external shocks.
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  • Date Issued: 2010

Wattle we do? alien eradication and the 'ecology of fear' on the fringes of a world heritage site, South Africa

- Merron, James Lawrence

When birthing makes the news : the depiction of women as a newsworthy item in Die Burger (Oos-Kaap)

- Preller, Cindy

  • Authors: Preller, Cindy
  • Date: 2010
  • Subjects: Mass media and women -- South Africa Childbirth -- South Africa Women -- South Africa Die Burger (Port Elizabeth, South Africa) Journalism -- South Africa -- 21st century Mass media -- Moral and ethical aspects -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3480 , http://hdl.handle.net/10962/d1002935
  • Description: The thesis “When birthing makes the news: the depiction of women as a newsworthy item in Die Burger (Oos-Kaap)” analyses a common, yet complex news topic in the South African print media due to the sensitive, often sensationalised, nature of the topic. The private experience of birthing is featured more and more in the public domain of newspapers because of widespread service delivery problems within the South African health department. Focussing on the Eastern Cape, I examine the representation of birthing in Die Burger (Oos-Kaap) in texts printed between 2005 and 2007, and scrutinise the media’s monitorial role of a self-appointed public hero acting on behalf of the women, to expose the poor conditions at government hospitals, specifically in the Nelson Mandela Bay region. How the women and their bodies are reported on, creates a discursive tension between the negative portrayals of the birthing women and the monitorial role of the media. The news values of sensationalism and profit are achieved with visceral representations of the reproductive functions of the birthing women. A poststructuralist feminist theoretical framework reveals discourses that perpetuate race, class and gender inequalities in the apparently socially-concerned sample of texts. A Critical discourse analysis (CDA) provides an approach and method to inform a close textual analysis of both the lexical and visual elements of the texts. The discourses in the sample differed from text to text. Despite these differences, the monitorial role of the media is still achieved. My research argues that acting in the public interest with sensationalist copy is still acting in the public interest. I conclude that it is not easy for newspapers to separate sensationalism from accountability. Media practitioners should be aware of their role in constructing women’s identities and be particularly thoughtful when reporting on birthing. In doing so, this research aims to improve the manner in which women and their bodies are reported on within the news industry.
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  • Date Issued: 2010

White rhinoceros populations in the Eastern Cape: distribution, performance and diet

- Kraai, Manqhai

  • Authors: Kraai, Manqhai
  • Date: 2010
  • Subjects: Rhinoceroses -- South Africa -- Eastern Cape , Rhinoceroses -- Habitat -- South Africa -- Eastern Cape , Rhinoceroses -- Behavior -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10692 , http://hdl.handle.net/10948/1297 , Rhinoceroses -- South Africa -- Eastern Cape , Rhinoceroses -- Habitat -- South Africa -- Eastern Cape , Rhinoceroses -- Behavior -- South Africa -- Eastern Cape
  • Description: White rhino populations did not occur historically in the Eastern Cape, South Africa (Skead 2007). They have, however, been introduced into a number of reserves within the Eastern Cape for reasons such as conservation, ecotourism and hunting. Based on the literature on the species, it was hypothesized that white rhinoceros would have been introduced in grass-rich habitats, as they are bulk grazers. White rhinoceros populations were further assessed in terms of population establishment by outlining their distribution and performance since introductions and this was done by extracting intercalving intervals from the literature of native populations and comparing such to the Eastern Cape intercalving intervals, extracted from data obtained from landowners. Finally, the diet of white rhinoceros was quantified, in order to identify plant species potentially at risk from white rhino herbivory using Shamwari Private Game Reserve as a study site. The distribution of white rhino in the Eastern Cape varies in terms of habitat and vegetation types. The majority (62%) of white rhino are located in grass-poor habitats and are primarily there for ecotourism purposes with only a small percentage kept for conservation purposes in the state reserves. Limited data for intercalving intervals of the white rhino in Eastern Cape are comparable to those of populations in the natural range. The ex situ conservation of white rhino in the Eastern Cape proved to be a success as population numbers have increased markedly since the first survey was conducted (Buijs 1999). The diet section of this study showed that white rhino are highly selective grazers even in a grass-limiting habitat which is dominated by browse. Twenty-five principal dietary items were identified in their diet, with only six being preferred in autumn. These are thus the plant species that could be the most vulnerable to white rhino herbivory. Supplementary food provision plays a big part of the feeding scheme of white rhino in Shamwari Private Game Reserve during the winter season, revealing the little confidence that the management has on natural resource availability to the animals at this time. These findings support the value of the Eastern Cape for ex situ conservation of white rhino, and highlight plant species potentially at risk. There is a need for further research on the population performance of these animals, and the plants identified here need to be monitored to assess white rhino impact on the vegetation
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  • Date Issued: 2010

Women, land rights and HIV/AIDS in Zimbabwe: the case of Zvimba communal area in Mashonaland West Province

- Arisunta, Caroline

  • Authors: Arisunta, Caroline
  • Date: 2010
  • Subjects: Land tenure -- Zimbabwe , AIDS (Disease) in women -- Zimbabwe , Agricultural productivity -- Zimbabwe , Women farmers -- Zimbabwe , Women in agriculture -- Zimbabwe , Widowhood -- Zimbabwe , Inheritance and succession -- Zimbabwe , HIV-positive persons -- Zimbabwe
  • Language: English
  • Type: Thesis , Masters , M Soc Sc (Rural Development)
  • Identifier: vital:11939 , http://hdl.handle.net/10353/233 , Land tenure -- Zimbabwe , AIDS (Disease) in women -- Zimbabwe , Agricultural productivity -- Zimbabwe , Women farmers -- Zimbabwe , Women in agriculture -- Zimbabwe , Widowhood -- Zimbabwe , Inheritance and succession -- Zimbabwe , HIV-positive persons -- Zimbabwe
  • Description: This study explores women’s access to land under the customary tenure system. It examines how the changes in land tenure, access and rights to land as a consequence of HIV/AIDS are affecting agricultural productivity, food security and poverty, with a specific focus on women who have lost their husbands to HIV/AIDS in Zvimba. Zvimba is a village community located in Zvimba District in the Mashonaland West Province of Zimbabwe. The study also discusses policy responses designed to cushion the impact of HIV/AIDS on local communities especially women living with HIV/AIDS. The study highlights the vulnerability of widows to land rights violations, mainly inflicted by relatives but sometimes by the wider community. The main form of abuse encountered included the use of abusive language, threats of evictions and at times, beatings. The legal route for seeking redress was rarely used. Fear of witchcraft, low educational levels and fear of causing conflict between children and their paternal relatives also led widows to abandon the fight for their rights. The study further reveals that widows are heavily exposed to dispossession of their land rights. HIV/AIDS has increased the vulnerability of widows and other women to threats and dispossession of their land and other property rights. Dispossession of arable fields was observed in the four wards. The dispossessions and threats to livelihoods were directly related to the HIV positive status of the widows. The findings from this study illustrate the predominant role that male members of the household or family have over land. Thus, culture and traditional practices still affect women in other cases, disadvantaging them in favour of men, as in inheritance of land and property in the household.
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  • Date Issued: 2010

Wounding and healing as paradox: towards the visual articulation of synthesis

- De Lange, Bev

  • Authors: De Lange, Bev
  • Date: 2010
  • Subjects: Psychology
  • Language: English
  • Type: Thesis , Masters , MTech (Fine Art)
  • Identifier: vital:8531 , http://hdl.handle.net/10948/1655 , Psychology
  • Description: The very notion of wounding can be argued to imply a process of healing. Indeed some wounds are at the outset designed to be instruments of healing. As ten years of my professional life were spent assisting in the surgical creation of such „wounds‟ in an operating theatre it is from this memory timeframe that I initiated the process of developing visual equivalents that become reflective of both wounding and healing. The operation theatre was also an environment from which I developed increased awareness of mind or psyche as an entity conceptually comprising both conscious and unconscious components. Within this context, it can be argued that the patient‟s state of mind moves between consciousness and forms of unconsciousness induced through anaesthesia. Through research into the writings of the psychoanalyst Carl Jung, I began to develop a greater understanding of the concepts surrounding the conscious and unconscious mind in relation to the development of consciousness as well as to the integration of opposites. It is from this understanding of a dynamic process within the mind itself that I have attempted to develop visual signifiers of paradox in order to give expression to symbols that are reflective of these processes and in so doing indicate the psychological journey towards synthesis and individuation.
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  • Date Issued: 2010

Writing the aerial dancing body a preliminary choreological investigation of the aesthetics and kinetics of the aerial dancing body

- Acker, Shaun Albert

  • Authors: Acker, Shaun Albert
  • Date: 2010
  • Subjects: Dance -- 19th century Dance -- 20th century Dance -- 21st century Aerialists Movement, Aesthetics of Feminine beauty (Aesthetics) Movement notation
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2129 , http://hdl.handle.net/10962/d1002361
  • Description: This mini-thesis investigates some of the nineteenth century socio-cultural ideals that have structured a connection between virtuosic aerial skill and bodily aesthetics. It views the emergence of a style of aerial kineticism that is structured from the gender ideologies of the period. It investigates the continual recurrence of this nineteenth century style amongst contemporary aerial dance works and outlines the possible frictions between this Victorian style of kineticism and contemporary aerial explorations. From this observation, a possible catalyst may be observed with which to relocate and inspire a study of aerial kinetics sans the nineteenth century aesthetic component. This kinesiological catalyst may be viewed in conjunction with the theories of ground-based kinetic theorist, Rudolph Laban’s choreutic study of the body in space. Thus, it may be possible to suggest and introduce a possible practical dance scholarship for aerial dance. This mini-thesis includes an introductory choreological investigation that draws on and integrates the disciplines of kinesiology; choreutic theory; existing aerial kinetic technique; musicology; and the physical sciences.
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  • Date Issued: 2010
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