Distributed generator (DG) resources are small scale electric power generating plants that can provide power to homes, businesses or industrial facilities in distribution systems. Power loss reductions, voltage profile improvement and increasing reliability are some advantages of DG units. The above benefits can be achieved by optimal placement of DGs. Whale optimization algorithm (WOA), a novel metaheuristic algorithm, is used to determine the optimal DG size. WOA is modeled based on the unique hunting behavior of humpback whales. The WOA is evaluated on IEEE 15, 33, 69 and 85-bus test systems. WOA was compared with different types of DGs and other evolutionary algorithms. When compared with voltage sensitivity index method, WOA and index vector methods gives better results. From the analysis best results have been achieved from type III DG operating at 0.9 pf.

In a global environment characterised by the growing role of science and technology in our economic, social, and political lives, an international research agenda has arisen to measure and understand how science and technology are perceived and evaluated by the public. In 2010, the South African Social Attitudes Survey included 20 items to measure public attitudes towards science, knowledge about science, and sources of information about science. This household survey was administered to a representative, stratified, random sample of 3183 participants. The findings were analysed through a bivariate analysis, and here we report on South African attitudes towards science and technology, how these have changed between 1999 and 2010, and where South African science attitudes fit on the canvas of global science attitudes. The data reveal a complex and shifting relationship between attitudes of promise and reservation towards science in South Africa. In the international context, South Africa has a unique 'fingerprint' of public attitudes towards science. The strongest demographic variable impacting on attitude towards science was educational attainment, followed by age. Gender had no impact on science attitude. This broad overview also highlights some directions for further research to meet the growing academic and policy interest in the interface between the institutions of science and the public.

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Power system security analysis plays key role in enhancing the system security and to avoid the system collapse condition. In this paper, a novel severity function is formulated using transmission line loadings and bus voltage magnitude deviations. The proposed severity function and generation fuel cost objectives are analyzed under transmission line(s) and/or generator(s) contingency conditions. The system security under contingency conditions is analyzed using optimal power flow problem. An improved teaching learning based optimization (ITLBO) algorithm has been presented. To enhance the system security under contingency conditions in the presence of unified power flow controller (UPFC), it is necessary to identify an optimal location to install this device. Voltage source based power injection model of UPFC, incorporation procedure and optimal location identification strategy based on line overload sensitivity indexes are proposed. The entire proposed methodology is tested on standard IEEE-30 bus test system with supporting numerical and graphical results. Ó 2015 Faculty of Engineering, Ain Shams University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).