Optimal power flow using differential evolution algorithm

This paper presents an efficient and reliable evolutionary-based approach to solve the optimal power flow (OPF) problem. The proposed approach employs differential evolution algorithm for optimal settings of OPF problem control variables. The proposed approach is examined and tested on the standard IEEE 30-bus test system with different objectives that reflect fuel cost minimization, voltage profile improvement, and voltage stability enhancement. The proposed approach results are compared with the results reported in the literature. The results show the effectiveness and robustness of the proposed approach.     

Characterization and correlation of crude oils from some wells in the North Western Desert,Egypt

Characterization and correlation of crude oils from some wells in the North Western Desert, based on six crude oil samples, were studied by different analytical techniques, including API gravity, sulfur content, nickel and vanadium, bulk compositions and saturated fraction obtained from gas chromatography have been studied. The results show that the crude oils are normal to medium aromatic oils, with high API gravity and high sulfur content. V, Ni, V/Ni and V/(V + Ni) reflecting oils might be sourced from non-clastic source rocks, possibly carbonates, deposited under anoxic-suboxic conditions. Bulk compositions revealing that the crude oils were derived from marine organic sources. While, the paraffins and naphthenes percent indicates that the oils belong to paraffinic to naphthenic oil types, deposited in slightly anoxic to suboxic conditions and contained marine organic matter. Thermal maturity data showed that the oil samples were generated from mature source rocks. This indicates the studied oil samples are well correlated with each other, where they are similar in their oil type maturation and source depositional environments.     

Petrographic and petrophysical characterization of some Paleozoic rocks,Um Bogma area,Southwest Sinai,Egypt

Sixty-two samples were collected from the five formations at Um Bogma area, (Southwest Sinai, Egypt). Nine samples were collected from Sarabit El Khedim Formation, ten samples were collected from Abu Hamata Formation, eighteen samples were collected from Adedia Formation, eight samples were collected from Um Bogma Formation and eighteen samples were collected from Abu Thora Formation.The Paleozoic rocks at Um Bogma area, consist mainly of sandstones, siltstones, shales, limestone and dolostones, which are unconformably overlie igneous and metamorphic rocks (granite, diorite and gneiss) of Precambrian age.The petrographic studies were applied to identify different rock units, different facies and its diagenetic history and to reveal its effect on the storage capacity properties. Different types of porosity (oversized, intergranular, fracture and vuggy porosities) have been identified based on the petrographic investigation of the studied thin sections.The Paleozoic sandstone rock samples are characterized by porosity average about 19% for Facies 1 (quartz wack) and about 18%for Facies 2 (quartz arenite) and permeability average 420?mD for Facies 1 (quartz wack) and 690?mD for Facies 2 (quartz arenite), so these rocks can be considered as good reservoir rocks. The Paleozoic carbonate rock samples (Facies 3) are characterized by poor porosity (less than 7%) and very low permeability (less than 0.5?mD), which caused by matrix and diagenetic processes and refer to bad reservoir rocks.Porosity can be linked to the two derived electrical properties (formation resistivity factor and electrical tortuosity) of the studied Paleozoic rocks at Um Bogma area. The electrical tortuosity has significant effects on both permeability and formation resistivity factor. The permeability decreases with increasing electrical tortuosity and the relation between both of them is inverse relationship with good coefficient of correlation. The permeability decreases with increasing electrical tortuosity and the relations between both of them are inverse relationships with high coefficient of correlation. The formation resistivity factor increases with increasing electrical tortuosity and the relations between both of them are positive relationships with a fair to very high coefficient of correlation.     

Oil: Source rock correlations of Al Baraka oil field,Komombo basin,South Egypt: An implication from biomarkers characteristics

The objectives of this study are the correlation between the oil samples recovered from the Lower Cretaceous reservoirs and Lower and Upper Cretaceous source rocks. The investigated biomarkers of five oils indicated the oils were derived from mixed marine and terrigenous (lacustrine) organic matter and deposited under suboxic to anoxic conditions. These oils were also generated from source rocks of high thermal maturity at the peak oil window. So, based on the molecular indicators of organic source input,depositional environment and maturity parameters of oils and extracts, we can conclude that the oil recovered from Al Baraka oil field were derived from Lower Cretaceous source rocks especially KomOmbo (B) source rocks where it reached the oil window. Furthermore, we can indicate that the other lower Cretaceous formations as Abu Ballas Formation will have the opportunity to generate and expel oil at the deeper part of the basin as shown in the eastern part of the basin.     

Image processing applications performance study on Cell BE and Blue Gene/L

Two image processing applications, edge detection and image resizing, are studied in this paper on two HPC platforms namely the Cell BE and the Blue Gene/L machines. In this paper we focus on the performance scalability of the studied applications. Our results show that the scale of the problem to be solved highly affects the fitness of the platform. If the data set size is to fit into the Cell core, the fast on‐chip inter‐core communication of a multi‐core system pays back for its high technology design. On the other hand, the overhead of the distant communication in the massively parallel Blue Gene/L machine will only show its benefits for huge data set size that otherwise mandates multiple round‐trip data communications between the local memory of a core and main memory. Copyright © 2010 John Wiley & Sons, Ltd.     

Early use of PbS nanotechnology for an ancient hair dyeing formula

Lead-based chemistry was initiated in ancient Egypt for cosmetic preparation more than 4000 years ago. Here, we study a hair-dyeing recipe using lead salts described in text since Greco-Roman times. We report direct evidence about the shape and distribution of PbS nanocrystals that form within the hair during blackening. It is remarkable that the composition and supramolecular organization of keratins can control PbS nanocrystal growth inside a hair.     

Cross-cultural differences in driving skills: a comparison of six countries

The first aim of the present study was to investigate the applicability of the two-factor structure (perceptual-motor skills by 11 items, e.g., "fluent driving"; safety skills by 9 items, e.g., "conforming to the speed limits") of the Driver Skill Inventory (DSI) among British, Dutch, Finnish, Greek, Iranian, and Turkish drivers. It was also hypothesized that the combination of self reported high ratings of perceptual-motor skills and low ratings of safety skills creates a serious risk for dangerous driving and road accident involvement. The second aim of this study was, therefore, to investigate this asymmetric relationship between perceptual-motor and safety skills in traffic penalties and accident involvement. Two hundred and forty two drivers were chosen from each of the six countries, matched for age and sex. The results of exploratory factor analyses together with target rotation showed that the two-factor structure of DSI found in "safe" Northern and Western European countries were highly congruent. However, the safety skills factor of DSI in Greece, Iran, and Turkey was relatively incongruent in spite of high factor similarity found in perceptual-motor skills. The asymmetric relationship between perceptual-motor and safety skills on traffic penalties was found in Finland and Turkey. A negative relationship between safety skills and the number of accidents was found both in Greece and Iran while a positive relationship between perceptual-motor skills and the number of accidents was found only in Iran.     

Rat testis as a radiobiological in vivo model for radionuclides

The radiobiological effect of intracellularly localised radionuclides emitting low energy electrons (Auger electrons) has received much attention. Most in vivo studies reported have been performed in the mouse testis. We have investigated the rat testis as an in vivo radiobiological model, with sperm-head survival, testis weight loss and also alteration in the blood plasma hormone levels of FSH and LH as radiobiological endpoints. Validation of the rat testis model was evaluated by using mean absorbed doses of up to 10 Gy from intratesticularly (i.t.) injected (111)In oxine or local X-ray irradiation. Biokinetics of the i.t. injected radionuclide was analysed by scintillation camera imaging and used in the absorbed dose estimation. By the analysis of the autoradiographs, the activity distribution was revealed. Cell fractionation showed (111)In to be mainly associated with the cell nuclei. External irradiations were monitored by thermoluminescence dosimeters. The sperm-head survival was the most sensitive radiobiological parameter correlated to the mean absorbed dose, with a D(37) of 2.3 Gy for (111)In oxine and 1.3 Gy for X rays. The levels of plasma pituitary gonadal hormones FSH and LH were elevated for absorbed doses >7.7 Gy. This investigation shows that the radiobiological model based on the rat testis has several advantages compared with the previously commonly used mouse testis model. The model is appropriate for further investigations of basic phenomena such as radiation geometry, intracellular kinetics and heterogeneity, crucial for an understanding of the biological effect of low-energy electrons.