Ideale vir die uitbouing van tegniese en beroepsonderwys in Suid-Afrika

Problems emanating from the colonial structure, and which tend to reduce man to being a “human machine”, are discussed, and it is indicated that these tend to impinge on the status oj technical and professional education and lower it. From the demands the modern human-machine system makes one’s full capacity for being human, the author draws the conclusion that in technical and professional training human development has to be given primary consideration. A discussion of the problems surrounding cultural change and modernization in post-colonial set-ups indicates the fact that technical and professional education has a unique education task and opportunity in South Africa too

Reducing the electricity cost of a Three-Pipe Water Pumping System – a case study using software

Efficient control is often the most cost-effective option to improve on the running cost of a ThreePipe Water Pumping System. However, the effect of changing the control strategy (i.e. on energy consumption) is usually difficult to predict. A new simulation tool, QUICKcontrol, was used to investigate the energy cost savings potential in a Three-Pipe Water Pumping System. The influence of pump scheduling, dam level set points, control parameters and different combinations thereof were investigated. The simulation models were firstly verified with measurements obtained from the existing system to confirm their accuracy for realistic control retrofit simulations. With the aid of the integrated simulation tool, it was possible to predict savings of R195 000 per year with an average 3.8 MW of load shifted out of peak times. These control strategies can be implemented in the pumping system with a direct payback period of less than 6 months

Measuring subdiffusion parameters

We propose a method to extract from experimental data the subdiffusion parameter $\alpha$ and subdiffusion coefficient $D_\alpha$ which are defined by means of the relation $=2D_\alpha/\Gamma(1+\alpha) t^\alpha$ where $$ denotes a mean square displacement of a random walker starting from $x=0$ at the initial time $t=0$. The method exploits a membrane system where a substance of interest is transported in a solvent from one vessel to another across a thin membrane which plays here only an auxiliary role. Using such a system, we experimentally study a diffusion of glucose and sucrose in a gel solvent. We find a fully analytic solution of the fractional subdiffusion equation with the initial and boundary conditions representing the system under study. Confronting the experimental data with the derived formulas, we show a subdiffusive character of the sugar transport in gel solvent. We precisely determine the parameter $\alpha$, which is smaller than 1, and the subdiffusion coefficient $D_\alpha$.Comment: 17 pages, 9 figures, revised, to appear in Phys. Rev.

Reducing the electricity cost of a Three-Pipe Water Pumping System – a case study using software

Efficient control is often the most cost-effective option to improve on the running cost of a ThreePipe Water Pumping System. However, the effect of changing the control strategy (i.e. on energy consumption) is usually difficult to predict. A new simulation tool, QUICKcontrol, was used to investigate the energy cost savings potential in a Three-Pipe Water Pumping System. The influence of pump scheduling, dam level set points, control parameters and different combinations thereof were investigated. The simulation models were firstly verified with measurements obtained from the existing system to confirm their accuracy for realistic control retrofit simulations. With the aid of the integrated simulation tool, it was possible to predict savings of R195 000 per year with an average 3.8 MW of load shifted out of peak times. These control strategies can be implemented in the pumping system with a direct payback period of less than 6 months

A review of South African research in atmospheric science and physical oceanography during 2000-2005

The purpose of this article is to review progress in the fields of atmospheric science and physical oceanography made by workers based at South African institutions over approximately the last 5 years. Research published by South African scientists working abroad is not included. Most published research in these fields falls within the broad areas of climate variability, climate change, aerosols and atmospheric pollution, seasonal forecasting, numerical modelling (both atmospheric and oceanic), and the physical oceanography of the Agulhas and Benguela current systems. Most but not all of the atmospheric science papers relate to South Africa or southern Africa; however, some work pertaining to the southern hemisphere as a whole or to other regions has been done. We note that funding and institutional support for atmospheric science and physical oceanography research in South Africa remains poor and this situation significantly hampers local efforts

Monitoring the oceanic flow between Africa and Antarctica: Report of the first GoodHope cruise

The southern ocean plays a major role in the global oceanic circulation role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air–sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February–March 2004

Monitoring the oceanic flow between Africa and Antarctica: report of the first Good Hope cruise

The Southern Ocean plays a major role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air-sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February-March 2004

Poly(N-vinylpyrrolidone) antimalaria conjugates of membrane-disruptive peptides

The concepts of polymer–peptide conjugation and self-assembly were applied to antimicrobial peptides (AMPs) in the development of a targeted antimalaria drug delivery construct. This study describes the synthesis of α-acetal, ω-xanthate heterotelechelic poly(N-vinylpyrrolidone) (PVP) via reversible addition–fragmentation chain transfer (RAFT)-mediated polymerization, followed by postpolymerization deprotection to yield α-aldehyde, ω-thiol heterotelechelic PVP. A specific targeting peptide, GSRSKGT, for Plasmodium falciparum-infected erythrocytes was used to sparsely decorate the α-chain ends via reductive amination while cyclic decapeptides from the tyrocidine group were conjugated to the ω-chain end via thiol–ene Michael addition. The resultant constructs were self-assembled into micellar nanoaggregates whose sizes and morphologies were determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The in vitro activity and selectivity of the conjugates were evaluated against intraerythrocytic P. falciparum parasites.© 2020 American Chemical Societyhttp://pubs.acs.org/journal/bomaf62021-11-06hj2021BiochemistryGeneticsMicrobiology and Plant Patholog