Central University of Technology

About: Central University of Technology is a education organization based out in Bloemfontein, South Africa. It is known for research contribution in the topics: Higher education & Population. The organization has 852 authors who have published 1478 publications receiving 13171 citations. The organization is also known as: Technikon Free State & Central University of Technology Free State.

Review of current methods for estimating areal reduction factors applied to South African design point rainfall and preliminary identification of new methods

Abstract: Design point rainfall estimates assume a uniform distribution of rainfall over a catchment, and hence are only representative for a limited area. For larger areas, areal reduction factors (ARFs) are used to convert design point rainfall depths/intensities to an average areal design rainfall depth/intensity for a catchment-specific critical storm duration and catchment area. This paper presents a review of ARF estimation methods used nationally and internationally, with comparisons of the South African methods in the C5 secondary drainage region using standard input variables. The comparison of different ARF estimation methods confirmed that the empirical methods adopted for general use in South Africa are based on a limited database of observed rainfall data and are used without local correction factors beyond their original developmental regions. This results in the characterisation of the actual rainfall process over a catchment, and translation into questionable design peak discharge estimates. Therefore, the ARFs in South Africa need to be re-investigated in the light of recent extreme flood events, utilising the longer periods of record and denser rain-gauge networks which are now available for analysis. The variation of ARFs with return period and with rainfall producing mechanisms also needs to be investigated. Updated ARFs developed and verified using local rainfall data will improve the accuracy of design hydrology for large catchments in South Africa when event-based rainfall-runoff deterministic methods are used.

Group work in higher education: a mismanaged evil or a potential good?

Abstract: This study focuses on the modal proposition that group work in the context of higher education has the potential to enhance learning among students, but has yet to reach its valid zenith of utility value in didactical practice. The particular characteristics of the small group in the context of higher education are described and supplemented by an explication of the small group learning process students partake in. This is followed by a brief examination of structured activities for group work; the assessment of group work; and the implications for the managing of group work in higher education. Empirically, the study explores the perceptions of students regarding group work. Results show that students are positively inclined towards group work and have constructive views regarding the nature of group work as a learning mode. Theoretically speaking, group work has a wealth of potential to offer to the lecturer and the learner. The complexity of the phenomenon leaves the lecturer with no choice but to take great care in the use of group work. The fact that group work is not viewed as a mismanaged evil leaves the door open for further use of this mode of teaching, learning and assessing in higher education. South African Journal of Higher Education Vol.18(2) 2004:131-149

Relationship Between Self-Efficacy Beliefs of Science Teachers and Their Confidence in Content Knowledge

Abstract: This exploratory survey examined the relationship between the science teachers' self-efficacy beliefs and content knowledge of selected chemistry concepts which form part of the South African National Senior Certificate curriculum. Participants were 190 physical science teachers (females = 44.4%, aged range 23 to 56 years) from the central province of South Africa. They completed a teaching confidence and self-efficacy scales. Data were analyzed for rank-order in confidence to teach regular science curriculum concepts and newer industry oriented concepts. Findings suggest that teachers' confidence and self efficacy were higher for established science concepts as compared to newer industrial applications.

Challenges to parental involvement in school governance

Abstract: Many parents find it difficult to embrace their governance role within public schools, with the exception of those within elementary schools. Despite the intention of the South African Schools Act of 1996 to change this situation, some primary schools reported a mixed-bag of responses regarding parental involvement in school governance. This article reveals that "young to middle-aged" parents display immense energy, inquisitiveness, and a desire to lead and be involved, while their older counterparts still accept and respect the unfolding of events at school without question. Uitdagings rakende die betrokkenheid van ouers in die bestuur van skole Baie ouers vind dit moeilik om hul bestuursrol binne openbare skole aan te gryp met uitsondering van ouers in aanvangsonderrigskole. Ten spyte van die poging van die Suid-Afrikaanse Skolewet van 1996 om die situasie te verander, verklaar sommige primere skole 'n mengelmoes van reaksies aangaande ouers se betrokkenheid in die bestuur van skole. Die artikel toon dat "jonger tot middeljarige" ouers baie energie en nuuskierigheid vertoon en 'n behoefte het om leiding te gee en betrokke te wees, terwyl hul ouer ewekniee steeds net die gebeure by die skool sonder enige bevraagtekening aanvaar en respekteer.

Varying percentages of full uniform shading of a PV module in a controlled environment yields linear power reduction

Abstract: Partial shading of a PV module has received much attention over the past few years, as it results in uneven cell power generation, compromising a PV system performance. Full uniform shading of a PV module has not received as much attention. This article correlates the percentage of full uniform shading of a given PV module within a controlled environment to its output power. The percentage of full uniform shading provided by shade nets was firstly determined. These shade nets are then used to cover a specific PV module (experimental system), while an identical PV module remains totally unshaded (control system). Increasing percentages of full uniform shading negatively affected the direct beam component in a linear way. Decreasing the light intensity falling on the PV model exhibited a linear increase in the percentage of output power reduction of the PV module. This is observed in that a shade net providing 36% of full uniform shading resulted in a 56% output power reduction, while a 63% full uniform shading net yielded 82% power reduction. These results hold a strong promise to improve current simulation modules that focus on determining the output power of a given PV array under specific environmental conditions or for specialised geographical locations.