635 research outputs found
Plagiarism in e-learning systems: Identifying and solving the problem for practical assignments
A big part of life long learning is the move from residential lectures to distance education. Distance education falls under the multi-modal policy of the teaching institution and thereby a change in student contact. The lecturer facilitating the distance education course is also faced with a problem where the quality and originality of submitted assignments need to be checked. This has always been a difficult task, as going through practical assignments and looking for similarities is a tedious job. Software checkers are available, but as yet, have not been integrated into popular online e-learning systems. If closer contact and warning to students are given at an early stage the problem is minimized as they know they are being closely monitored. As will be shown in this article, plagiarism is a current problem with online practical submissions. We will also show how this problem can be minimized through the integration of plagiarism checking tools and other checking methods into e-learning systems
Challenges for successful planning of open and distance learning (ODL): A template analysis
How to plan an open and distance learning (ODL) unit in higher education is not clearly described in the literature. A number of ODL facilities at residential universities have not been successful because of a lack of planning or because of failure to ensure that all the different systems for ODL delivery were in place and functioning. This paper sheds light on how to plan strategically and how to implement an ODL unit at an existing university.A template analysis was used to construct a road map for ODL planners. We used this analytical tool to organise data from a large collection of articles, books, and documents from 1980-2010. We purposefully chose template analysis as a document analysis process to foster the recurring themes found in published articles on planning and implementing ODL facilities in higher education.The results indicate four main strategies for successful implementation of an ODL unit. The template consists of strategic planning, policies, systems, and challenges. It was concluded that the template for ODL planning offers new insight into distance education. It could be used as a foundation for ODL planning, implementation, monitoring, and evaluation. We recommend further research on the template with the aim of theory construction for ODL planning and implementation
The characterisation and automatic classification of transmission line faults
Includes bibliographical references.A country's ability to sustain and grow its industrial and commercial activities is highly dependent on a reliable electricity supply. Electrical faults on transmission lines are a cause of both interruptions to supply and voltage dips. These are the most common events impacting electricity users and also have the largest financial impact on them. This research focuses on understanding the causes of transmission line faults and developing methods to automatically identify these causes. Records of faults occurring on the South African power transmission system over a 16-year period have been collected and analysed to find statistical relationships between local climate, key design parameters of the overhead lines and the main causes of power system faults. The results characterize the performance of the South African transmission system on a probabilistic basis and illustrate differences in fault cause statistics for the summer and winter rainfall areas of South Africa and for different times of the year and day. This analysis lays a foundation for reliability analysis and fault pattern recognition taking environmental features such as local geography, climate and power system parameters into account. A key aspect of using pattern recognition techniques is selecting appropriate classifying features. Transmission line fault waveforms are characterised by instantaneous symmetrical component analysis to describe the transient and steady state fault conditions. The waveform and environmental features are used to develop single nearest neighbour classifiers to identify the underlying cause of transmission line faults. A classification accuracy of 86% is achieved using a single nearest neighbour classifier. This classification performance is found to be superior to that of decision tree, artificial neural network and naĂŻve Bayes classifiers. The results achieved demonstrate that transmission line faults can be automatically classified according to cause
Commentary on “site managers manual on energy and water efficient housing”
An attempt to address the general lack of instruction material on energy effi cient housing existing in South Africa needs to be evaluated by the target audience. This becomes even more relevant where valuable financial support of sponsors is used for the compilation of such an effort. The manual is critically evaluated and a survey is included. The survey was conducted by means of a survey questionnaire sent to tertiary education institutions offering courses for construction managers. Most of the respondents found the contents not to be relevant to the study field and to be inadequate as undergraduate study material
Historiese stof in Magersfontein, o Magersfontein!
’n Werk wat soveel teenstrydige reaksies soos Magersfontein, o Magersfontein uitgelok het, bly ’n tergende uitdaging, vir die wat ’n belangstelling in die letterkunde het, om deur te dring tot die kern en betekenis, die tema, die prinsipe van struktuur en tegnieke, die perspektief wat die skrywer bedoel het om op sy romanwêreld te gee, en tot die wese van die vertelhouding. Dit is geen geringe onderneming nie
Transformational leadership, job autonomy and role-breadth self-efficacy : their influence on proactive behaviour in entry-level graduate roles
This study investigated the model on the antecedents of proactive behaviour as identified by Den Hartog and Belschak (2012) within the context of entry-level graduate roles (n = 76). A survey was devised which included the use of a five-point Likert-type scale. It was then administered to graduates in entry-level roles in various industries in South Africa to measure the different variables stipulated by the model. When data was analysed, the results revealed that transformational leadership (inspirational), task-related role-breadth self-efficacy (RBSE), and people-related RBSE correlated significantly and positively with proactive behaviour. Transformational leadership (performance) and job autonomy obtained non-significant correlations with proactive behaviour. The results also revealed that job autonomy, task-related RBSE and people-related RBSE did not moderate the relationship between transformational leadership (inspirational or performance) and proactive behaviour. This meant that the display of transformational leadership did not lead to a significant increase in proactive behaviour in low autonomy, low RBSE situations or in high autonomy, high RBSE situations as hypothesised. The unique characteristics of entry-level graduate roles are highlighted by the study - the significance of this model on proactive behaviour in a general employee context potentially may not be relevant to a graduate context. The findings contribute towards research evidence on the development of proactive behaviour in entry-level graduate roles
The first two electron linear accelerators in South AFrica
The electron linear accelerator is considered by many leading radiotherapy centres throughout the world as the most suitable equipment for the treatment of cancer. There are good reasons for this opinion, and some physical aspects are summarised here.S. Afr. Med. J., 48, 1004 (1974)
A South African review of harmonic emission level assessment as per IEC61000-3-6
Large-scale renewable power producing plants are being integrated into South African networks.
Network operators need to ensure that Renewable Power Plants (RPP) do not negatively affect the
power quality levels of their networks, as harmonics amongst others could become a concern.
IEC 61000-3-6 details a method for allocating voltage harmonic emission limits for distorting loads.
This method works well for the allocation of emission limits; however it does not address the
management of harmonic emissions once a plant is connected to the network. The management of
harmonic emissions requires that network operators measure or quantify the emissions from loads and
generators to determine compliance. Post-connection quantification of harmonic levels and
compliance is a challenge for network operators. The question asked is “How should a network
operator measure/quantify the harmonic emissions of a load/generator to establish compliance with the
calculated limits as per IEC 61000-3-6”.
This paper reviews within a South African context methods of assessing harmonic emission levels and
then evaluates these methods by means of field data. Opportunities for improvement are identified
and operational requirements discussed
The permanent deformation of circular cylindrical shells subjected to internal explosive loading
Bibliography: pages 68-69.This work describes what is primarily an investigation into methods for estimating the maximum permanent deformation of a circular cylindrical shell subjected to internal explosive loadings. A complete rigid-plastic analysis of the transient response is performed. Subsequently the effects of material properties are included. Finally the theoretical predictions are compared with the experimental results obtained from a series of tests on aluminium shell specimens
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