Produktiwiteitsverhoging: ’n bestuurswetenskaplike en prinsipiële beskouing

The pursuit of high productivity is not a goal in itself, but rather regulates the attempt to raise a country's standard of living. Since the standard of living is dependent on the relationship between the total output and input of all businesses, the productivity of a single business has a great influence. Increasing productivity is considered to be an extremely important management function. I f productivity is regarded as the measuring instrument of successful management, then the management process and, more specifically, management by objectives is the method for achieving this. It is management’s responsibility to create the necessary climate of productivity and increased productivity. The approach must be one which achieves a balance between task-orientation and people-orientation. Consequently the purpose and meaning of work should also be reconsidered. Work is not a goal in itself but must always be seen within the wider context of God’s cultural mandate to man. When everyone understands the meaning of work we will emerge from the so-called ‘reward psychosis’, and reward will be offered according to need and achievement. Reward and work fulfilment will lead to the creation of a work environment which is meaningful of the worker, which promotes increased productivity, and which allows self-actualization toflourish. Management is capable of creating and maintaining these circumstances which will increase productivity

Addressing Content, Convergent and Predictive Validity of Implicit Pain-Related Fear in Chronic Low Back Pain

Chronic low back pain (CLBP) is a common condition that can lead to emotional distress and physical disability. Fear of pain, a phobic-like response to pain, can contribute to significant avoidance behavior and is associated with disrupted physical and emotional functioning. While questionnaires remain the standard for measurement of pain-related fear, recent work has explored the use of implicit methods. This study aimed to use an implicit measure, the Implicit Relational Assessment Procedure (IRAP), to assess convergent and predictive validity of implicit pain-related fear in relation to explicit self-report measures. Seventy-four participants with CLBP were recruited and completed the pain-related fear IRAP, along with self-report measures of pain-related fear, distress, and disability, as well as three physical performance tasks. Both explicit and implicit biases were demonstrated in participants, suggesting the presence of pain-related fear, however, implicit pain-related fear failed to demonstrate convergent and predictive validity. Therefore, implicit pain-related fear, while present in patients with CLBP, may not provide additional utility above and beyond explicit measures of pain-related fear

Heat transfer in two and three-dimensional single span greenhouses

Abstract: The purpose of this paper is to investigate the heat transfer in two-dimensional and three-dimensional cavities representing a single span greenhouse. This investigation is conducted numerically using Computational Fluid Dynamics (CFD). The heat transfer and temperature fields driven by buoyancy forces are investigated. The research commences with the validation of a few fundamental geometries used as the building blocks for a large commercial greenhouse. The first fundamental geometry is a square filled with air. The CFD results for a square cavity are first evaluated against experimental results found in the literature for both two and three dimensional cavities. The heat transfer inside the cavities is then investigated and compared to those found in the literature. A reasonably good comparison between the numerical CFD results and the experimental results was found for both the two- and three-dimensional cavities. Based on the validated CFD models, two three-dimensional single span greenhouses containing a pitched roof were investigated to determine the effect of design alterations on the heat transfer within the cavity. The results were also compared to two-dimensional greenhouses with a 30 and 45 degree roof angle respectively. Results found that there are significant differences between the two and three-dimensional cases when the average Nusselt number is considered, especially for a greenhouse containing a roof angle of 45 degrees. Temperature distributions were also found to vary significantly throughout the three-dimensional greenhouses

Numerical investigation of a naturally ventilated greenhouse containing stacked benches

Abstract: The rapidly growing concerns of energy efficient methods have increased the emphasis on natural air ventilation in indoor environments such as greenhouses. Naturally ventilated greenhouses are used to create a microclimate that does not fluctuate majorly with the ambient conditions. This microclimate is of vital importance since it directly influences the quality and quantity of crop production. This study investigates the natural ventilation in a single-span greenhouse with a roof vent opening configuration using a two-dimensional Computational Fluid Dynamics (CFD) model. The numerical model is first successfully validated against data found in a study by Ould Khaoua. The two benches are then replaced by stacked type benches in order to investigate its effect on the indoor climate inside the greenhouse, which is the main objective of this study. The temperature and velocity profiles at the various stack heights were observed and it is noted that the temperature distributions are not significantly affected by the type of benches. However, the air velocity values are seen to be significantly lower for the lower racks when stacked benches are used. This indicates that care should be taken when placing plants on the lower racks as this could lead to non-uniform crop production

The effect of geometrical electrical cable configurations on heat transfer in cable ducts

Abstract: Please refer to full text to view abstrac

Longitudinal Polarization in KL→μ+μ−K_L \to \mu^+ \mu^- in MSSM with large tanβtan\beta

A complete experiment on decay $K_L \to l^+ l^-$ will not only consist of measurement of the decay rates but also lepton polarization etc. These additional observations will yield tests of CP invariance in these decays. In $K_L$ and $K_S$ decays, the e mode is slower than the $\mu$ mode by roughly $(m_e/m_\mu)^2$ \cite{sehgal1}. As well discussed in literature \cite{herczeg} the Standard Model contribution to the lepton polarization is of order $2 \times \sim 10^{-3}$. We show that in MSSM with large \tanbeta and light higgs masses ($\sim 2 M_W$), the longitudinal lepton polarization in $K_L \to \mu^+ \mu^-$ can be enhanced to a higher value, of about $10^{-2}$.Comment: version appeared in Physics Letters B, minor correction

Regstellende aksie: ’n etiese perspektief

Affirmative action: an ethical perspective. The scrapping of certain relevant laws of the apartheid era can not immediately undo the wrongs of apartheid. What is essentially needed is compensation of some kind for every individual or group who has been affected by it. The question is whether affirmative action can be ethically justified; is it inherently 'right or wrong’? In this paper different approaches to affirmative action and the normal phases of implementation of affirmative action are investigated. The best known ethical theories are then used to adjudicate the relevance ami ethical justification of affirmative action. In the final analysis six different levels of ethical decision-making are considered. The conclusion arrived at is that affirmative action is unavoidable but that there are a number o f pitfalls awaiting the unwary. To implement affirmative action successfully certain prerequisites must be met