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Modification of endurance wave analysis based on New-wave theory Saeed Mohajernassab, Mohammad Ali Dastan Diznab, Hamid Mehdigholi, Mohammad Saeed Seif∗ and Mohammad Reza Tabeshpour Department of Mechanical Engineering, Center of Excellence in Hydrodynamics and Dynamics of Marine Vehicles, Sharif University of Technology, Tehran, Iran (Received 30 June 2014; accepted 28 January 2016) The main objective of this investigation is to modify endurance wave analysis (EWA) based on New-wave theory for convenient assessment of offshore structures under extreme waves. EWA is a novel time history based approach to evaluate structural performance in various excitation levels of wave loading by intensifying wave records. In this article, modifications are proposed to determine appropriate time duration and intensifying trend for reliable and practical assessment of offshore structures. In this way, a simplified model of a real jacket platform is utilised to investigate the application of this approach under extreme wave conditions in the Persian Gulf and results are compared with typical three hour random wave simulations. It is shown that in extreme waves, except resonance states, proposed method can estimate the structural response with acceptable accuracy and very low computational costs. Keywords: New-wave theory; endurance wave analysis; jacket platform; extreme waves; assessment منبع دانلود Tabeshpour_Modification-of-endurance-wave.pdf

Physicochemical Assessment Of Groundwater Quality In Akure, Southwestern Nigeria Original Article, C5 Duvbiama Omolara Atarhe and Egbuna Chukwuemeka Kingsley. Journal. Civil Eng. Urban. 3(1): 25-28. 2013 ABSTRACT: This paper investigates the physicochemical properties of 36 hand-dug wells in the North-western part of Akure, Nigeria. 36 hand-dug wells were analysed for some physicochemical parameters such as temperature, pH, electrical conductivity, redox potential (Eh), total dissolved solids, Ca, Mg, Na, K, HCO3, Cl, SO4, total alkalinity, total hardness and acidity. Results showed that all the wells except for wells 8 and 31 have their physicochemical parameters within the WHO guideline value. The high level of these physicochemical parameters in wells 8 and 31 could be attributed to geologic formation of these areas. Since most of the occupants of the area depend on these well water supplies for drinking and other domestic needs, it is recommended that any source of contamination should a minimum of thirty five meters away from any source of contamination. Keywords: Physicochemical parameter, well, water quality, WHO, Assessment منبع: [Hidden Content] دانلود: [Hidden Content],%203(1)%2025-28.pdf JCEU-2013-C5, 3(1) 25-28.pdf

Assessment of Ground-Water Quality in the South-East of England Original Article, B38 Louis IA and Egbuna CK. Journal. Civil Eng. Urban. 2(6): 214-219. 2012. ABSTRACT:This study assesses the groundwater quality in the South-East England. Borehole water samples were collected at different locations across 7 different sites in the South-East of England. 14 physicochemical and 2 microbiological parameters (E. coli and enterococci spp) of the groundwater were analysed. Results showed that although all the physicochemical parameters met the WHO and EC Water Directive (98/83/EEC) guideline values, the presence of E.coli and enterococci were detected in the entire sites except for one. The presence of these micro-organisms could be attributed to the proximity to the sewage treatment discharge which could have mixed with the ground water via seepage and intrusion of animal faeces into the groundwater. Keywords:E.coli, Groundwater Quality, WHO, Assessment, Physicochemical Parameter. منبع: [Hidden Content] دانلود: [Hidden Content],%20B%2038%20214-219.pdf JCEU, B 38 214-219.pdf