Spatial and seasonal distribution of selected persistent organic pollutants and phenolic derivatives along the course of the Buffalo River in the Eastern Cape Province of South Africa
- Authors: Yahaya, Abdulrazaq
- Date: 2017
- Subjects: Organic water pollutants Water -- Purification -- Organic compounds removal
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/5939 , vital:29448
- Description:
Persistent organic pollutants (POPs) fall under a group of synthetic chemicals known for their persistence in environmental matrices such as soil and water, and are used in industrial, domestic and agricultural applications. Because of their volatility and lipophilicity, POPs can be transported far away from their point sources and bio-accumulate in food and in fatty tissues of humans and animals. In view of their toxicity and carcinogenicity some organic pollutants such as polychlorinated biphenyl (PCBs), organochlorine pesticides (OCPs) and phenolic derivatives (chlorophenol and nitrophenol) have been classified by United State Environmental Protection Agency (USEPA) and World Health Organization (WHO) as priority pollutants. The present work evaluated the distribution patterns of 19 polychlorinated biphenyls congeners, 17 organochlorine pesticides and selected phenolic derivatives (USEPA 11-priority pollutants) in the Buffalo River, in the Eastern Cape Province, South Africa between December 2015 and May 2016. The Liquid-liquid extraction technique was used for PCBs, OCPs and phenolic derivatives in the river water samples. Silica gel and florisil clean up were carried out for PCBs and OCPs samples respectively and analyzed with gas chromatography electron capture detector (GC/ECD). Phenolic compounds were derivatized and analyzed by gas chromatography mass spectrometer (GC/MS). Limits of detection (LOD), limit of quantitation (LOQ) and relative standard deviation (RSD) for the PCBs were 10 to 330 ng/L, 20 to 1,060 ng/L and 1.18 to 14.1 percent respectively. The LOD, LOQ and RSD for the OCPs were from 20 - 60 ng/L, 110 - 530 ng/L and 0.02 - 0.06 percent, while the corresponding values for the phenolic derivatives were 10 to 70 ng/L, 33 to 222 ng/L and 1.99 - 10.86 percent. In summer, the concentrations of PCBs, OCPs and phenolic derivatives ranged from
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- Date Issued: 2017
The development of a translucent low fired porcelain casting slip using South African raw materials
- Authors: Ruiters, Mellaney Bualin
- Date: 2017
- Subjects: Arts -- Research -- South Africa , Pottery -- Research -- South Africa , Ceramics -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/20004 , vital:29026
- Description: The purpose of the research was to develop a translucent low fired porcelain casting slip using South African raw materials, due to the ever increasing electricity tariffs in South Africa as well as the physical deterioration put on the elements and brickwork in electric kilns when fired to traditional porcelain temperatures. Traditional porcelain bodies that can be purchased from South African suppliers are required to be fired to between 12000C and 13000C. The commercially prepared porcelains when tested produced white vitrified bodies but were lacking in translucency. Local ceramic artists are therefore compelled to import their porcelains from overseas suppliers if they require a white translucent porcelain but this is still requires a firing temperature well above 12000C. It has been shown that by using South African ceramic raw materials and adjusting a Parian ceramic formula using a selected frit; a low fired translucent porcelain can be made that matures below 12000C. The addition of paper fibres to the non-plastic porcelain was necessary to reduce the high shrinkage rate and prevented the clay from cracking and tearing in the firing process. With the further adjustments to the formula by the addition of calcium triphosphate true white translucent porcelain was produced. Without this last adjustment the porcelain would be an off-white colour due to the impurities found in the South African ceramic raw materials which are mainly contaminated with iron oxide. It was found that the following formula produced a white translucent porcelain which vitrified at 11900C and satisfies the original concept in the title stated above.
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- Date Issued: 2017
Assessment of the Eastern Cape Provincial Public Service Commission in promoting public service ethics
- Authors: Butana, Vulikhaya
- Date: 2018
- Subjects: Public administration -- Moral and ethical aspects Civil service ethics Public administration
- Language: English
- Type: Thesis , Masters , Public Administration
- Identifier: http://hdl.handle.net/10353/10295 , vital:35391
- Description: After the fall of the apartheid government with discriminatory laws and the rise and dawn of democracy in South Africa (SA), the government had to restructure the Public Service (PS). The creation and development of PS legislations and policies to regulate the PS took place. The PSC in 1999 was developed to monitor and steer the operation of the PS. The main objective of this study is to assess the Public Service Commission (PSC) in promoting the professional and ethical environment in the Public Service (PS). The PSC is an independent and impartial body or institution which is mandated by the Republic of South African Constitution of 1996 (Act No.108 of 1996), Public Service Commission Act and the Public Service Act. Chapter ten of the Constitution gives PSC a mandate to ensure that the egalitarian values and principles governing public administration are maintained by government departments, organizations, parastatals and administrations providing the PS, where in this study focus on the promotion of ethics. The methodology used in this study is qualitative research methodology. The study used desktop research where by a data was collected using books, journal articles, academic papers, online information and media reports. The findings of this study highlighted that non-compliance to rules and regulations, lack of policy implementation, limited financial and human resources are still the major problems facing the South African Public Service (SAPS). However, the study recommends that, the PSC must work closely with government departments, promotion of ethics workshops and conferences. In a nutshell, the PSC could improve by developing and regularly reviewing policies, procedures, practices and institutions influencing ethical conduct in the public service.
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- Date Issued: 2018
Financial development, income inequality and poverty: case of a selected SADC countries
- Authors: Leve, Samkele
- Date: 2019
- Subjects: Finance Economic development Income distribution
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/16918 , vital:40785
- Description: The financial sector plays a pivotal role in an economy of a country; hence the importance of financial development cannot be underestimated. Financial development is widely regarded as another conduit through which income inequality and poverty can be alleviated, however both theoretical and empirical literature does not reach consensus on the effect of financial development on income inequality and poverty. Against this background, the study empirically examines the effect of financial development on income inequality and poverty in selected Southern African Development Community (SADC) countries, employing the Generalised Method of Moments (GMM) technique for the period 1980 to 2011. Based on the inequalitydecreasing and Mckinnon Conduit effect, two models which link financial sector development and inequality and financial sector development and poverty were estimated using five different dimensions of financial development. Empirical results revealed that financial development overall does have an impact on income inequality and poverty in the selected SADC countries. An interesting observation from the empirical results is that the actual dimension of financial development plays a significant role in determining the relationship between financial development, income inequality and poverty in the SADC region. The impact of financial depth on poverty is not obvious in the study, depending on the variable used. On the relationship between financial system stability, income inequality and poverty, results reveal that a stable financial system is beneficial to the poor. Financial efficiency does not appear to have a significant role in reducing income inequality and poverty in the selected SADC countries. Overall, the findings from the study indicate that financial access or financial inclusion and financial stability is what reduces poverty instead of mere financial sector development at a broader level.
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- Date Issued: 2019
Psychosocial well-being and the sexual behaviour of orphaned adolescent males in Bizana local municipality
- Authors: Gqumani, Phumlani
- Date: 2020
- Subjects: Teenage boys -- Psychology Youth -- Sexual behavior -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc. Sci (Psychology)
- Identifier: http://hdl.handle.net/10353/18118 , vital:42234
- Description: The aim of the study was to explore the relationship between the psychosocial wellbeing and the sexual behaviour of orphaned adolescent males. The rationale of the study was to determine out whether the relationship exists between psychosocial wellbeing of orphaned adolescent males and their sexual behaviour (e.g. multiple sexual partners, sexual debut, and unprotected sex). The sample size of the purposively selected participants constituted 201 participants from Grade 07 to Grade 12. The study took place from Bizana Local Municipality, Eastern Cape. The researcher used Statistical Package for Social Sciences. The descriptive analysis and inferential statistics were used to analyse the data. Some of the findings of the study included the following From the hypotheses I drink alcohol and I watch pornography and that is how I learned to have sex, it became apparent that adolescent males who drink alcohol, watched pornography. The alternative hypothesis was confirmed with 8.5% of adolescent males drink alcohol and watch pornography compared to 8.0% who do not drink alcohol but watch pornography. There was no relationship between the hypotheses, my friends are aggressive and commit crime and I started having sex at age 13-16 and 17-20 years as 31. 4% of adolescent males who started having sex at the age of 17-20 years, 1.9% have friends who were aggressive and commit crime compared to 2.9% who started having sex at the age of 13-16 years who have friends who were aggressive and commit crime. Based on the findings of the study, it became clear that some adolescent males are resilient despite their social status and the study may be recommended for future studies.
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- Date Issued: 2020
Resource Allocation Framework in Fog Computing for the Internet of Things Environments
- Authors: Vambe, William Tichaona
- Date: 2020
- Subjects: Internet of things Cloud computing
- Language: English
- Type: Thesis , Doctoral , PhD (Computer Science)
- Identifier: http://hdl.handle.net/10353/18498 , vital:42575
- Description: Fog computing plays a pivotal role in the Internet of Things (IoT) ecosystem because of its ability to support delay-sensitive tasks, bringing resources from cloud servers closer to the “ground” and support IoT devices that are resource-constrained. Although fog computing offers some benefits such as quick response to requests, geo-distributed data processing and data processing in the proximity of the IoT devices, the exponential increase of IoT devices and large volumes of data being generated has led to a new set of challenges. One such problem is the allocation of resources to IoT tasks to match their computational needs and quality of service (QoS) requirements, whilst meeting both task deadlines and user expectations. Most proposed solutions in existing works suggest task offloading mechanisms where IoT devices would offload their tasks randomly to the fog layer or cloud layer. This helps in minimizing the communication delay; however, most tasks would end up missing their deadlines as many delays are experienced during offloading. This study proposes and introduces a Resource Allocation Scheduler (RAS) at the IoT-Fog gateway, whose goal is to decide where and when a task is to be offloaded, either to the fog layer, or the cloud layer based on their priority needs, computational needs and QoS requirements. The aim directly places work within the communication networks domain, in the transport layer of the Open Systems Interconnection (OSI) model. As such, this study follows the four phases of the top-down approach because of its reusability characteristics. To validate and test the efficiency and effectiveness of the RAS, the fog framework was implemented and evaluated in a simulated smart home setup. The essential metrics that were used to check if round-trip time was minimized are the queuing time, offloading time and throughput for QoS. The results showed that the RAS helps to reduce the round-trip time, increases throughput and leads to improved QoS. Furthermore, the approach addressed the starvation problem, a phenomenon that tends to affect low priority tasks. Most importantly, the results provides evidence that if resource allocation and assignment are appropriately done, round-trip time can be reduced and QoS can be improved in fog computing. The significant contribution of this research is the novel framework which minimizes round-trip time, addresses the starvation problem and improves QoS. Moreover, a literature reviewed paper which was regarded by reviewers as the first, as far as QoS in fog computing is concerned was produced.
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- Date Issued: 2020