43867 research outputs found
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The role and impact of social media in white informal settlements
Get PDFAbstract: Little is known and understood about social media and social capital in urban informal settlements. Moreover, white informal settlements are anomalous in South Africa – hidden and understudied in a country where wealth distribution is skewed in favour of the minority white population. Limited information is available on these impoverished white communities. In fact, even their physical locations mostly remain officially undocumented. This does not suggest or imply, however, that the residents of white informal settlements are silent or disconnected from the world outside their immediate communities. This study addresses a void in the body of knowledge available on social media and social capital in white informal settlements in South Africa. This doctoral study explores the role and impact of social media in five white informal settlements in Gauteng – South Africa’s financial capital and most densely populated province. Through in-depth interviews, the researcher learned that Facebook and WhatsApp are enormously popular among the study’s participants. They use these platforms to connect with others (some who are previously known to them and others who are part of shared-interest groups), for emotional support, for important information about their immediate environment, and, perhaps most remarkably, to survive. Facebook itself has emerged as a powerful fundraising tool for participants bridging a divide between themselves, who are in need, and those who are willing and able to donate and provide aid (“sponsors”). In this regard, Facebook and WhatsApp groups have rendered themselves essential platforms to source food, clothing, furniture and other necessities...Ph.D. (Communication Studies
First-principles design of hybrid carbon nitride (C2N) with gallium sulphide and gallium selenide two-dimensional (2D) materials as high-performance photovoltaic cells
Get PDFAbstract: Please refer to full text to view abstract.M.Sc. (Chemistry
Fungal diversity and mycotoxin contamination of some selected food commodities from Ivory Coast
Get PDFAbstract: This study surveyed fungi and mycotoxins in important food crops consumed in Ivory Coast. To achieve this, the following local food items (attieke, cassava flakes, chilli, gnangnan, haricot, melon, millet, okra, rice, white maize and yellow maize) were sampled from local markets (Adjame, Cocody and Youpougon) in Abidjan, Ivory Coast. They were screened for fungal contamination based on morphological characters and confirmed by PCR using the internal transcribed spacer 1 and 4 primers (ITS1 and ITS4). A total of 227 isolates were morphologically identified withisolates dominated by species within the genera Aspegillus (54.9 %) followed by Penicillium (23.3 %) and Fusarium (14.3 %). Few isolated species were confirmed in other genera which include Alternaria, Chaetomium, Cladosporium, Epicoccum, Emerica, Rhizopus and Trichoderma spp.The highest mean fungal load of 6.85 x 105 CFU/g was found in white maize while the lowest mean level of 4.39x104CFU/g was recorded in cassava flakes. The subset of isolates were identified using ITS1 and ITS4, as Aspergillus species found to be most frequentin cassava flakes, chilli, gnangnan, haricot, rice and yellow maize. Penicillium species were also found frequent in chilli, haricot and rice, while Fusarium species were frequent in melon and millet...M.A. (Biotechnology
The geology of the Daitari Greenstone Belt, Singhbhum Craton, India - insights into early life 3.5 Ga ago
Get PDFAbstract: Archaean greenstone belts offer the opportunity to study the dynamic early Earth conditions. The Singhbhum Craton (SC) of India hosts several volcano-sedimentary greenstone sequences that preserve Archaean rocks locally exceeding 3.5 Ga. The Daitari Greenstone Belt (DGB) comprises a well-perpetuated submarine volcano-sedimentary succession of mafic-ultramafic rocks, felsic volcanics dated at c. 3.51 Ga, and intercalated banded chert, shale and iron formation. Common volcanic rocks include komatiite, pillow basalt, and felsic volcaniclastic rocks. Felsic volcanic rocks dating back to c. 3.53-3.51 Ga from the Daitari and Gorumahisani greenstone belts mark a period of widespread felsic magmatic event in the SC. Sedimentary rocks of the DGB are dominated by chemical precipitates of banded black-and white-chert, thinly laminated black chert, banded iron formation and minor siliciclastic rock such as shale. The DGB hosts altered silicified/carbonated volcanic rocks and cherts, an assemblage typical for Palaeoarchaean successions...Ph.D. (Geology
Factors affecting sustainable infrastructure delivery in South Africa - a case of Gauteng province
Get PDFAbstract: Infrastructure plays a crucial role in the economic growth and development of any country; therefore, it is important to ensure adequate investments for the delivery of infrastructure services. This paper assessed factors affecting the development of sustainable infrastructure in South Africa. The identified factors can be utilised by government as reference to enhance the delivery of sustainable infrastructure. To achieve the objective of the study, Quantitative data was collected. The study used a sample size of 57 out of the 65 questionnaires (a response rate of 87.7%) which were answered by professionals in the built environment viz. Architects, Property Developers, Quantity Surveyors, Engineers, Construction and Project Managers. The data collected was then analysed and interpreted using IBM Statistical Package for Social Science (SPSS) computer software to provide mean item scores, standard deviations and Cronbach’s alpha. Given the explored factors which affect the delivery of sustainable infrastructure, the results have established that due to developers habit of building to maximise profit only, not for end-users’ comfort and the initial high cost required to develop sustainable infrastructure were the major factors that affect the delivery of sustainable infrastructure. It is recommended that the government develop clear, stable and credible policies that will attract investors who will be committed to inject financial resources into infrastructure development and alter the existing building regulations to complement the sustainable development goals
A competency framework for coaches working in coaching development centres
Get PDFAbstract: Orientation: Globalisation and the new world of work has changed the labour market, resulting in highly complex, volatile and dynamic environments. Organisations are dependent on highly skilled human capital to not only survive but also thrive. Selecting and developing talent is thus becoming a business necessity. Assessment centres (ACs) and development assessment centres (DACs) have become popular tools to manage talent because of the successful outcomes it provides. In recent years, there has been a noticeable increase in the awareness of the benefits that coaching can offer in the AC environment as well as the development of coaching development centres (CDCs). However, research on CDCs is still limited. For CDCs to provide the same rigorous results as ACs and ADCs, a well-defined competency framework is needed for coaches working in a CDC. Research purpose: The aim of this study was to explore the required competencies and formulate a competency framework for coaches working in a CDC. Motivation for the study: Coaching, which is at the heart of coaching practices such as executive coaching, one-on-one coaching, team coaching and CDCs, requires a clear set of coaching competencies to ensure that it deliver its mandate to its clients: individuals, organisations and the profession. Coaches in a CDC environment work in a different context and require different competencies. A competency framework for CDC specifically is therefore needed. Research approach/design and method: Adopting a qualitative methodology, a self-completed questionnaire was administered to eight participants, followed by a semi-structured interview. Lastly, the competency framework was verified by an expert panel of five experts using the Delphi technique. Main findings: A final competency framework consisting of 25 competencies, of which 14 are considered as core competencies, was validated. Practical/managerial implications: The study contributes to the understanding of the unique behavioural demands associated with coaches operating in the context of a CDC. It provides a conceptual and practical framework of what competencies are needed to work successfully and effectively as a coach in a CDC, and ultimately enhance the effectiveness of a CDC. Contribution/value-add: Utilising this framework in practice will enable us to use candidates best suited to the role of a coach at a CDC, and will enhance the overall success of such centres
A robust technique for detecting glaucoma from fundus
Get PDFAbstract: Glaucoma has been credited to be the foremost cause of preventable loss of sight in the world second only to cataract. Its effect on the eye is usually irreversible and can only be prevented by early detection. In this paper, we developed a glaucoma detection technique. This technique includes a modified U-net model and an extreme gradient boost (XGB) algorithm. The modified U-net model was utilized to segment both the optic cup and the optic disc from the fundus images. The extreme gradient boost algorithm was utilized to analyze extracted features from segmented optic cups and discs and hence detect glaucoma. The modified U-net model was both trained and tested on the DRIONS, DRISHTI-GS, RIM-ONE-V2 and the RIM-ONE-V3 databases. When tested for optic disc segmentation on the four databases, the model achieved the following average dice-scores: 0.96 on RIM-ONE-V3, 0.97 on RIM-ONE-V2, 0.96 on DRIONS, and 0.97 on DRISHTI-GS. The XGB algorithm achieved an accuracy of 88 % and an AUC-ROC of 92.9 % in detecting glaucoma from the segmented optic disc and optic cup. The proposed glaucoma detection technique achieves a state-of-the-art accuracy and useful for observing structural changes in optic cup and optic disc. The advantage of the proposed modified U-net model is that it has much fewer parameters to be trained when compared to the original U-net model and hence faster training time and cheaper training cost
Autism spectrum disorder through the lens of the Theory of Mind : African perspectives
Get PDFAbstract: The prevalence of Autism Spectrum Disorder (ASD) in Africa is increasing unprecedentedly. Yet, most researches and practices in ASD within African communities employ Eurocentric approaches to identification, screening, diagnosis, and interventions. This tends to increase the risk of late diagnosis and comorbidity clamored in Africa, given that Eurocentric approaches are inadequate in expounding ASD for typical African cultural diversity. Extant literature offers a general trajectory to the development and understanding of ASD without specific attention to cultural variability. This article drew from Baron-Cohen's mind-blindness theoretical framework to explain the ASD trajectory in Africa African context. We drew from African contextualization of the ToM and ASD to argue for an augmented mind-blindness framework for parents-oriented ASD surveillance in African communities. We further propose that ASD can be screened between the ages of 5 and 12 months through Afro-centric frameworks. The implications of our findings are that content and context are important variables in the research and practices of ASD
FUZZY-MOORA based optimization of machining parameters for machinability enhancement of titanium
Get PDFAbstract: The aim of this study is to determine the optimal combination of process parameters when machining commercially pure titanium grade 2. The unification of Multi objective optimization based on ratio analysis (MOORA) and fuzzy approach has applied to optimize the process parameters. Three process parameters i.e. cutting speed, tool overhang, and microhardness have been varied at three levels each and a total of twenty seven experiments have been conducted based on Taguchi’s L27 design of experiment technique. Cutting force, tool flank wear, and average surface roughness have been considered a machinability indicators to measure the process performance. Feed rate and depth of cut have been kept constant. Successful optimization is done and results show that machining titanium at higher cutting speed (140 m/min) and higher tool overhang length (65 mm) with medium hardness (1934 HV) results in lower cutting force, tool flank wear, and surface roughness. Outcomes of the present work reveal that the hybrid fuzzy-MOORA method is convincing enough to obtain the best process parameter combination for the best machinability while machining titanium type difficult-to-machine materials
Constructing, understanding and interpreting energy poverty in Zimbabwe : a postmodern perspective
Get PDFAbstract: Energy poverty is well acknowledged in the global public and scholarly discussions. Nonetheless, it is habitually analysed in isolation from the discourse through which it is framed, produced, represented and known. Using Zimbabwe as a case study, inductive qualitative research reveals that there is one main discourse associated with energy poverty: net deficit (supply-demand mismatch). This discourse is expressed by narratives that have competed for dominance in the Zimbabwean energy sector (2012-present), in particular, the effect of changes in the climate, vandalism of electricity infrastructure, the impact of sanctions, and the low rate of renewable energy adoption, are analysed..
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