Keuring van kwaliteitstudente vir 'n universiteit

The selection of the quality students for a university. During the period 1965-1985, there was a sharp increase in student numbers at universities in the RSA. The increase in student numbers was much higher than the economic o r population increases. More and more matriculants apply for admission to university , despite the fact that university education has become very expensive. Nowadays the selection of students is more important than it has been in the past

Foraging strategies of coexisting lacertid lizards in the arid Tankwa Karoo Basin of South Africa

The original publication is available at http://africanzoology.journals.ac.za/pubFour lacertid lizards, Pedioplanis laticeps, P. lineo-ocellata, Meroles knoxii and Nucras tessellata, occur sympatrically on the arid plains of the Tankwa Karoo Basin in South Africa. The aim of this study was to evaluate the significance of foraging strategy in resource partitioning among the four species, allowing them to co-occur in a structurally simple system with a limited number of potential niches. Previous workers already identified P. lineo-ocellata and M. knoxii as sit-and-wait foragers and N. tessellata as an active forager. We recorded data on three foraging variables: movements per minute, proportion of time spent moving, and proportion of attacks on prey whilst moving, for juveniles and adults of P. laticeps. By comparing the foraging data obtained for P. laticeps to those for other lacertid species, we were able to demonstrate that adult P. laticeps are ambush foragers.We also noted a significant ontogenetic shift in foraging behaviour in P. laticeps, and, due to a significantly higher frequency of short brief movements, we classified juveniles as mixed foragers. The sharing of an ambush foraging strategy by at least three of the four lacertid species co-occurring on the Tankwa plains, suggests considerable overlap along the trophic dimension of ecological space. This overlap presumably promotes occupation of separate microhabitats by the three ambush foragers in the Tankwa Karoo Basin.Publisher's versio

Biochemical evaluation of the nutrition status of urban school children of 12-15 years - riboflavin status

No Abstract

Classification of White Cultivar Wines by Origin using Volatile Aroma Components

Stepwise discriminant analysis was applied to gas chromatographic data of some volatile compounds obtmiieabjiTreonextracliOii"of dry white table wines. By means of this statistical method, successful classifications according to origin of Colombar wines from two regions, and Chenin blanc wines from three regions, were obtained. The components with the highest discriminatory value were i-amyl acetate, hexyl acetate and i-butanol, in the case of the Colombar wines and hexanol and 2-phenyl ethanol in the case of the Chenin blanc wines

The clinical and biochemical effects of riboflavin and nicotinamide supplementation upon Bantu school children using maize meal as carrier medium

A comprehensive clinical, biochemical and technological investigation was undertaken to establish the feasibility of ,enriching maize meal with riboflavin and nicotinamide. It was clear from the results that the addition of these vitamins to, maize satisfied all the prerequisites of a -scientifically sound enrichment scheme, as laid down by the NNRI. It was found that the addition of 1 mg of riboflavin and 10 mg of nicotinamide per 400 g maize ,meal was adequate to effectively reduce the incidence of .subclinical deficiency of these two vitamins among Bantu schoolchildren. Since the enrichment was found to be -effective, as well as technologically and economically jeasible, it is strongly recommended that a compulsory national maize enrichment scheme be introduced with the .least possible delay

Differentiation between Wines Originating from Different Red Wine Cultivars and Wine Regions by the Application of Stepwise Discriminant Analysis to Gas Chromatographic Data

Stepwise discriminant analysis (SDA) was applied to gas chromatographic data of some volatile compounds extracted with freon from red wines. By means of this statistical method, Pinotage and Cabernet Sauvignon wines (1978 vintage) could be classified into separate groups, the most effective variables being hexanol and i-amyl acetate. Pinotage wines from three, and Cabernet Sauvignon wines from two localities (1979 vintage) were subjected to classification according to origin. Successful classifications were obtained using the variables ethyl acetate, ethyl caprate, i-amyl acetate as well as a compound tentatively identified as i-valeric acid

Objective quality rating of Pinotage wine

Relationships between wine composition and three quality parameters were investigated employing a linear multiple regression statistical model. For this purpose a least squares curve fitting computer programme was applied to analyses of 17 Pinotage wines for 6 fatty add esters. Overall quality, taste and aroma ratings were determined by a taste panel and utilized as dependent variables. lt was found that 2 esters viz. n-hexylacetate and ethyl-n-octanoate allowed excellent prediction equations to be set up for the quality ratings when incorporated into multiple regression equations.Objektive Beurteilung der Weinqualität bei der Sorte PinotageDie Beziehungen zwischen der Weinzusammensetzung und drei Parametern der Weinqualität wurden untersucht, wobei das statistische Modell einer mehrfachen linearen Regression verwendet wurde. Zu diesem Zweck wurden die bei 17 Weinen der Sorte Pinotage gewonnenen Analysenergebnisse über 6 Fettsäureester in ein Computerprogramm zur optimalen Kurvenanpassung eingegeben. Durch ein Gutachtergremium wurden die Gesamt-Weinqualität, der Geschmack und der Geruch bewertet; die Daten dieser Qualitätsbeurteilung wurden als abhängige Veränderliche benützt. Es wurde festgestellt, daß 2 Ester, nämlich n-Hexylacetat und Äthyl-n-octanoat eine ausgezeichnete Vorhersage der Weinqualität ermöglichten, wenn ihre Werte in Mehrfachregressions-Gleichungen eingesetzt wurden

Smart home : energy management system for demand side management

ENGLISH ABSTRACT: Please refer to full text for abstractDu Plessis, D. & Randewijk, P. J. 2014. Smart home: Energy management system for demand side management, in Proceedings of the First International Conference on the use of Mobile Informations and Communication Technology (ICT) in Africa UMICTA 2014, 9-10 December 2014, STIAS Conference Centre, Stellenbosch: Stellenbosch University, Department of Electrical & Electronic Engineering, South Africa, ISBN: 978-0-7972-1533-7.The conference is available at http://mtn.sun.ac.za/conference2014/See also the record http://hdl.handle.net/10019.1/95703With South Africa’s energy grid currently under severe pressure due to a lack of planning, electricity prices have escalated. This has forced consumers to look toward finding innovative ways to reduce their consumption. The aim of this research project was to create a system that assists in the reduction of household power consumption by simplifying the process of power saving. This is done by enabling consumers to remotely monitor and control their household devices. To achieve this goal, a power management system was designed that consists of a Beaglebone black, the main electronic controller, and a circuit for measurement and control. The measurement circuit measures the power consumption, it is then sent to Trintel’s SMART Platform enables users to remotely monitor and control the devices by using a web-based interactive graphical user interface