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The South African electricity supply industry (ESI) is dominated by a state-owned and vertically integrated utility, Eskom, which ranks seventh in the world in terms of size and electricity sales; 92% of electricity is generated from coal. Data is presented to provide a snapshot of the current situation (2002). The paper examines the rationale for reform and restructuring of the South African ESI.

Recycled polylactic acid (PLAr) was reinforced with treated nanocellulosic hemp fibers for biocomposite fabrication. Cellulosic fibers were extracted from hemp fibers chemically and treated enzymatically. Treated nanocellulosic fibers (NCF) were analyzed by Fourier-transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Biocomposite fabrication was done with PLAr and three concentrations of treated NCF (0.1%, 0.25%, and 1% (v/v)) and then studied for thermal stability and mechanical properties. Increased thermal stability was observed with increasing NCF concentrations. The highest value for Young’s modulus was for PLAr + 0.25% (v/v) NCF (250.28 ± 5.47 MPa), which was significantly increased compared to PLAr (p = 0.022). There was a significant decrease in the tensile stress at break point for PLAr + 0.25% (v/v) NCF and PLAr + 1% (v/v) NCF as compared to control (p = 0.006 and 0.002, respectively). No significant difference was observed between treatments for tensile stress at yield.

Public policy requires public support, which in turn implies a need to enable the public not just to understand policy but also to be engaged in its development. Where complex science and technology issues are involved in policy making, this takes time, so it is important to identify emerging issues of this type and prepare engagement plans. In our horizon scanning exercise, we used a modified Delphi technique. A wide group of people with interests in the science and policy interface (drawn from policy makers, policy adviser, practitioners, the private sector and academics) elicited a long list of emergent policy issues in which science and technology would feature strongly and which would also necessitate public engagement as policies are developed. This was then refined to a short list of top priorities for policy makers. Thirty issues were identified within broad areas of business and technology; energy and environment; government, politics and education; health, healthcare, population and aging; information, communication, infrastructure and transport; and public safety and national security.

A method of estimating surface radioactivity concentrations of key anthropogenic radionuclides from NaI(Tl) pulse-height distribution observed at a monitoring station (MS) was discussed. In the estimation, a realistic assumption on geometric distribution of source and obstacles around the detector of the MS including the infiltration of radionuclides into the ground was used and the results were compared with ones with a commonly used assumption of a uniformly distributed plane source. The surface radioactivity concentration was determined by comparing the count rates at the full-energy peak ranges between observation and calculation with an electron-photon transport code EGS5. It was shown that the estimated absolute values of concentration differed by a factor of ∼1.5 depending on the assumption of infiltration depth. The estimated surface concentrations of (131)I, (134)Cs and (137)Cs were in good agreement with ones determined by the in situ measurements with an HPGe detector and the cumulative values of daily surface depositions.

Abstract The adoption rate and stringency of building energy standards in the U.S. have been increasing since the mid-1990s as a result of the Energy Policy Act mandate of 1992 (EPAct). Current evidence on the energy savings that accrue from commercial building energy standards is based on engineering simulations, which do not account for realized behaviour once a standard is actually adopted. This paper uses quasi-experimental variation in commercial building energy standard adoptions to estimate their effect on realized electricity consumption and cost-effectiveness. In states induced by EPAct to adopt an energy standard where all new nonresidential construction was erected under a commercial standard, electricity consumption per service worker is lower by about 12%, and total commercial electricity consumption is lower by 10%. Including early adopters and never-adopters to the analysis leads to a downward bias in the treatment effect. The realized electricity savings in the EPAct states represent three quarters of predicted simulated savings, and electricity saved in 2010 came at a cost of approximately 7.7 cents per kWh.

The solution of an electric circuit problem is only valid if the circuit elements have been validly modelled. The iron-cored coil is a common nonlinear circuit element, especially in power system circuits, where the iron core is laminated grain-oriented silicon-iron sheet. This paper attempts to show that eddy-current loss modelling in such a core is at least as important as hysteresis loss modelling, and demonstrates the accuracy of linear modelling of the eddy-current effect. If the circuit analyst has confidence in this complete model he can then decide which aspects of the model can be ignored with impunity when studying such circuit phenomena as ferroresonance, subharmonics and inrush current.