Visual warning signals associated with rockfalls in deep-level gold mining are embedded in a misleading and competing background. Due 10 the relatively high incidence of rockfall accidents and the relatively high involvement of novice mine workers in accidents, the ability of mine workers to discriminate visually between dangerous. and safe rock conditions was examined. Stimuli were presented to participants with the aid of stereoscopic slides and responses were analysed in terms of the Theory of Signal Detection. The results confirmed the contention that underground experience as well as skills training improves significantly the ability of mine workers to discriminate visually between dangerous and safe rock. I. IntroductionThe study described in this paper is concerned with the visual detection of warning signals associated with dangerous rock conditions in underground mining. The importance of investigating accidents caused by dangerous rock is evident from the fact that the incidence of these accidents in gold mining has remained virtually unchanged since 1940 (South Africa, Department of Mines 1976). While mining engineers were successful in preventing an increase in the rock fall fatality rate as mining operations were performed at deeper levels, the constant trend of these accidents is alarming, since accident prevention programmes currently in use appear to be ineffective in reducing the number of accidents of this nature.From a behaviour point of view it is useful to distinguish between rockfalls preceded by warning signals and rockfalls without prior warnings. A reasonable assumption is that' violent' rockfalls (such as rockbursts) are not preceded by warning signals. In a sample of 482 fatal accidents caused by falls of rock, Wagner and Tainton (1976) found that approximately 40% of the accidents were caused by violent rock failures. Their finding suggests that about 60% of the rock falls may have been preceded by warning signals.There appear to be three kinds of warning signals which could indicate the existence ofdangerous rock. Firstly, geological considerations such as bedding planes, discontinuities, fracture patterns and the type of rock could provide indications of dangerous rock. Secondly, factors related to support systems such as lay-out, deterioration over time and the quality of support provide evidence of the safety in work areas. Thirdly, occurrences of loose rock on stope faces and hanging walls can be used as predictors of rockfalls (Blignaut 1977).It is difficult to determine the frequency with which each of these warnings of danger occurs. However, from the study of fatalities in strike gullies (Wagner and Tainton 1976) it can be inferred that geological and support considerations provide about 62 % and 20%, respectively, of the warning signals. No obvious cause in 18% of the rock falls could be found.These findings, however, provide no basis for estimating the frequency in occurrences ofloose rock, since loose rock could be associated with each of the 'geological " 'support' and' ...
Individuality, collectivity and locus of control as micro variables of diversity. The principal aim of the study was to construct an instrument to measure individuality and collectivity as micro variables of diversity in the South African context. The Individuality-collectivity Inventory was applied to 326 university students. A factor analysis on 80 items yielded two factors. These factors were interpreted as collectivity and individuality. The two scales were subjected to an item analysis and yielded reliability coefficients of 0,86 and 0,910. A secondary aim of the study was to determine whether any correlation exists between individuality, collectivity and locus of control. The two sub-scales of the Individuality-collectivity Inventory were correlated with the three sub-scales of the Locus of Control Inventory. Statistically significant positive correlations were found to exist between individuality, internal locus of control and autonomy. The implications of the findings on the management of diversity are discussed.<p> <strong>Opsomming</strong> <br>Die hoofdoel van die studie was om 'n instrument vir die meting van die konstrukte individualiteit en kollektiwiteit as mikroveranderlikes van diversiteit in die Suid-Afrikaanse konteks daar te stel. Die Individualiteit-kollektiwiteitskaal is op 326 universiteitstudente toegepas. 'n Faktorontleding op 80 items het twee faktore tot gevolg gehad/ naamlik Individualiteit en Kollektiwiteit. Die twee skale is vervolgens aan 'n itemontleding onderwerp en betroubaarhede van 0,86 en 0,910 is onderskeidelik opgelewer. 'n Sekondere doelwit van die studie was om te bepaal of daar 'n verband tussen individualiteit, kollektiwiteit en lokus van beheer bestaan. Die twee sub-skale van die Individualiteitkollektiwiteitskaal is met die drie sub-skale van die Lokus van Beheer-vraelys gekorreleer. Statisties beduidende positiewe korrelasies bestaan tussen individualiteit, interne lokus van beheer en outonomie. Die implikasies van die bevindinge vir die bestuur van diversiteit word bespreek
In 2011 the Curriculum and Assessment Policy Statement (CAPS) for History at senior secondary school level was released. The content selection was directly influenced by the notion that History supports citizenship within a democracy. This opened the avenue for women's history to be introduced on senior secondary level. The aim of this article is twofold, namely to motivate the need to integrate women's history in implementing the senior secondary History CAPS by evaluating the content where women features and to provide an historical overview of Afrikaner women's role in South African history as an example of integrating Afrikaner women's history in the teaching of the CAPS content. The theories and methodologies of gender history are of the utmost importance to realise the civic aims of the CAPS, but the discussion of gender is beyond the scope of this article. This article identifies the lack of focus on women in the History CAPS despite the claim that history supports citizenship within a democracy by also representing gender-issues. Challenges to integrating women's history are then outlined. As an example of how women's history can relate to the major CAPS topics, an integrative and compensatory history of Afrikaner women is provided through evaluating women's "sense of independence" by describing their role in key events that shaped South African history, resistance against colonialism, and the development of proto-nationalism.
<p>From a perceptual point of view it is not clear whether, and under what conditions, the presence of colour in television commercials aids the processing of information. In this study it was argued that the way in which colour is used, would have an effect on the comprehension and memory of children regarding television commercials. It was found that colour, when used in a "concrete" fashion, aids the comprehension process. The results of the study also show that the "concrete" as well as the "symbolic" use of colour have a positive effect on the memory of children for the content of television commercials. <br></p><p><strong>Opsomming</strong> <br>Vanuit 'n perseptuele benadering is dit nie duidelik of, en onder watter omstandighede, die teenwoordigheid van kleur in televisie advertensies die prosessering van inligting positief bei'nvloed nie. In hierdie studie is daar van die standpunt uitgegaan dat die wyse van kleurgebruik 'n effek sal he op die begrip en geheue van kinders ten aansien van televisie advertensies. Daar is gevind dat kleur, wat op 'n "konkrete" manier gebruik word, die begripsproses bevorder. Die resultate van die studie toon ook dat sowel die "konkrete" as "simboliese" gebruik van kleur 'n positiewe effek op die geheue van kinders ten opsigte van televisie advertensie inhoud het.</p>
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