580 research outputs found
Students with disabilities’ experience in South African higher education – a synthesis of literature
This state of the art review paper offers a synthesis of published studies on students with disabilities’ experience in South African higher education since 1994, when a democratically elected government came to office. The article presents a review of published studies describing the experiences of students with disabilities in South African higher education (SAHE) in the period 1994-2017. In order to obtain a perspective on the experiences of students with disabilities in South African higher education institutions, a synthesis of the findings and implications of South African studies relating to students with disabilities in SAHE is provided. Three aspects will be discussed namely: (a) conceptualisation of disability; (b) access, inclusion and participation in higher education; and (c) supporting mechanisms for students with disabilities. From this, challenges, areas needing further studies, lessons learnt, approaches and policy implications for policy-practitioners and institutions are suggested
Performance Evaluation of Pastors in East Zimbabwe Conference
Problem
There has been no consistent and effective way of evaluating the performance of pastors in the East Zimbabwe Conference. In most cases the evaluating is only done for the purpose of identifying ordination candidates and is based only on quantifiable goals that include baptisms, tithe returns, and submission of reports. Due to the rapid growth of the church in terms of personnel, number of churches and membership, and the vast geographical territory, the need for an evaluation instrument is critical.
Method
The study was descriptive and designed around research questions that helped determine the job description of the pastor. Surveys, interviews and discussions were used in data collected from members, pastors, current and former administrators. Literature read was helpful in authenticating the practice, while the biblical perspective stimulated learning as it interfaced with secular theories of leadership and management.
Results
Key focus areas that reflect job description (competencies) of pastors were identified. An evaluation instrument relevant to the East Zimbabwe Conference was developed and pretested, and made ready for application.
Conclusions
A generative evaluation process is necessary and helpful to the professional development of the leadership and management skills of the pastor. The process benefits the individual pastor as well as the congregation, as they mutually centre on mission goals and objectives that are met through competent leadership
Fast Daily Interfraction and Intrafraction Prostate Repositioning for High Precision Radiotherapy
The research described in this thesis is focused on development and clinical evaluation of image-guidance solutions for correction of both inter- and intrafraction prostate motion in external beam radiotherapy. Corrections are based on planar imaging of implanted gold markers with MV and kV beams. The main advantages of the developed system include (1) high positioning accuracy, (2) minimal increase in fraction duration, (3) high degree of automation, i.e. minimal operator interference, (4) remote controlled couch re-positioning, (5) minimal additional imaging dose. Another important objective of the research was the assessment of residual errors, including organ deformation and rotation, to establish appropriate planning margins.
One of the main findings of the research is that implanted gold markers allow for fast daily correction of translational errors in prostate radiation therapy with high accuracy. An investigation of intrafraction positioning errors which occur during the treatment delivery revealed that intrafraction errors partially reproduce from day-to-day, thereby limiting margin reduction in prostate radiotherapy if not corrected. Another finding was that deformation of the seminal vesicles limits margin reduction with daily online translation corrections based on implanted markers. Furthermore, the benefit of rotation corrections in addition to translation corrections was insignificant. Finally, electronic portal imaging devices (EPIDs) have significantly facilitated time and workload efficient strategies for managing daily positioning errors with minimal extra imaging dose to the patient
The identification and remote detection of alien invasive plants in commercial forests: An Overview
Invasive alien plants are responsible for extensive economic and ecological damage in forest plantations. They have the ability to aggressively manipulate essential ecosystem structural and functional processes. Alterations in these processes can have detrimental effects on the growth and productivity of forest species and ultimately impact on the quality and quantity of forest wood material. Using direct sampling field-based methods or visual estimations have generally expressed moderate success owing to the logistical and timely impracticalities. Alternatively, remote sensing techniques offer a synoptic rapid approach for detecting and mapping weeds affecting plantation forest environments. This paper reviews remote sensing techniques that have been used in detecting the occurrence of weeds and the implications for detecting S. mauritianum (bugweed); one of the most notorious alien plant invaders to affect southern Africa. Gaining early control of these alien plant invasions would reduce the impacts that may permanently alter our forested ecosystems, contributing to its successful eradication and promoting sustainable forest management practices. Furthermore, the review highlights the difficulties and opportunities that are associated with weed identification using remote sensing and future directions of research are also proposed
Effects of different building blocks designs on the statistical characteristics of Automated Zone-design Tool output areas
Prior to any census, the country usually gets demarcated into small geographic units called census enumeration areas, districts or blocks. In most countries, these small geographic units are also used for census dissemination. In cases where they are not used for census release, they are normally used as building blocks for developing output areas or they are aggregated to higher spatial levels in an effort to preserve privacy or confidentiality. Buildings blocks are therefore, of significant importance towards results that could be drawn from either aggregated higher level or from output areas developed using these small geographic areas. This paper aimed at evaluating the effects of different building blocks on the statistical characteristics of output areas generated using the Automated Zone-design Tool (AZTool) computer program. Different spatial layers (such as Enumeration Areas (EAs), Small Area Layers (SALs) and SubPlaces) from the 2001 census data were used as building blocks for the generation of census output areas with AZTool program in both rural and urban areas of South Africa. One way-Analysis of Variance (ANOVA) was also performed to determine statistical significance of the AZTool results. Results showed that the AZTool output areas generated from smaller areas (EAs and SALs) tend to be more homogeneous than the ones generated from larger areas (SubPlaces) when using dwelling type and geotype as homogeneity variables. The output areas from smaller areas also had narrower population distribution and more compact shapes than their counter-parts. In addition, the AZTool optimised output areas from the smaller areas allowed a clear distinction of the scale effects than output areas from larger areas. It was concluded that indeed different building blocks did have an impact on the statistical qualities of the AZTool optimised output areas in both rural and urban settings in South Africa.Keywords: AZTool; Building blocks; Enumeration areas; Output areas; Scale effects; Small Area Layers; SubPlace
Land Use Land Cover Change in the fringe of eThekwini Municipality: Implications for urban green spaces using remote sensing
Concerns on urban environmental quality, increasing knowledge on impacts of climate change and pursuit for sustainable development have increased the need for past, current and future knowledge on the transformation of remnant urban fringe green ecosystems. Using land-cover change modeler and a Markov chain analysis on multi-temporal SPOT imagery, this study sought to determine a twenty two-year past and future land use and land cover trend and its implication on green spaces in an eThekwini Municipal Area’s peripheral settlement. Results show a consistent pattern of decline in land use and land cover types associated with green spaces and an increase in impervious surfaces. The study confirms recent urban bio-physical transformation and anticipated increased pressure on peripheral urban green spaces in eThekwini Municipality. These changes can be attributed to natural urban growth and government led efforts like the Reconstruction and Development Programme. Findings in the study highlight the challenges faced by eThekwini Municipality, and indeed other South Africa’s urban areas in maintaining urban green spaces and mitigating related implications like those associated with climate change. This study further demonstrates the value of multi-temporal remotely sensed datasets in planning, optimization and sustainable management of urban landscapes
Remote sensing bio-control damage on aquatic invasive alien plant species
Aquatic Invasive Alien Plant (AIAP) species are a major threat to freshwater ecosystems, placing great strain on South Africa’s limited water resources. Bio-control programmes have been initiated in an effort to mitigate the negative environmental impacts associated with their presence in non-native areas. Remote sensing can be used as an effective tool to detect, map and monitor bio-control damage on AIAP species. This paper reconciles previous and current research concerning the application of remote sensing to detect and map bio-control damage on AIAP species. Initially, the spectral characteristics of bio-control damage are described. Thereafter, the potential of remote sensing chlorophyll content and chlorophyll fluorescence as pre-visual indicators of bio-control damage are reviewed and synthesised. The utility of multispectral and hyperspectral sensors for mapping different severities of bio-control damage are also discussed. Popular machine learning algorithms that offer operational potential to classify bio-control damage are proposed. This paper concludes with the challenges of remote sensing bio-control damage as well as proposes recommendations to guide future research to successfully detect and map bio-control damage on AIAP species
Assessment of the Contribution of WorldView-2 Strategically Positioned Bands in Bracken fern (Pteridium aquilinum (L.) Kuhn) Mapping
In the eThekwini Metropolitan Area, mitigation of the Bracken fern (Pteridium aquilinum (L.) Kuhn) invasion within the KwaZulu-Natal Sandstone Sourveld (KZNSS) has been identified as a major environmental priority. To facilitate informed interventions, reliable Bracken fern spatial distribution is necessary. Earlier efforts to map the fern using lower spatial and spectral resolution imagery have been unsuccessful. Consequently, this study sought to determine the reliability of the “new generation” World View-2 (WV-2) image characterised by higher spatial and spectral resolution in delineating the fern invaded areas. The eight band WV2 image was atmospherically corrected and spectrally resized as the SPOT-5 wavebands, additional bands and all bands. The classification accuracy was compared to results from the SPOT-5 image. Results showed that classification based on WV-2s additional bands had superior classification accuracy than the rest of the categories. Furthermore, classification based on all the WV-2s bands and the traditional bands perfomed better than the SPOT-5 image in delineating areas covered by the fern. These findings indicate the value of of the “new generation” imagery characterised by higher spatial and spectral resolution in improving the accuracy of the fern invaded landscapes
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