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Elewa H.H.,National Authority for Remote Sensing and Space science NARSS | Fathy R.G.,General Authority for Rehabilitation Project and Agricultural Development GARPAD | Qaddah A.A.,Egyptian Environmental Affairs Agency EEAA
Hydrogeology Journal | Year: 2010

The Darb el-Arbain study area is in the southern Western Desert of Egypt and has been attracting increasing developmental interest in the last few decades, especially since agricultural development of the southern Baris area, where the groundwater resources of the Nubian Sandstone Aquifer System (NSAS) have been utilized for the cultivation of valuable lands. Due to the proven high potential of both groundwater and land resources, determining the priority areas for sustainable hydrogeological development becomes a necessity. A geographic information system, as a platform for geospatial modeling techniques, has been built, which depends on the recently collected data about the NSAS, in addition to the published databases. Certain criteria of practical value, like depth to groundwater, hydraulic conductivity, groundwater salinity, sodium adsorption ratio, and the safe yield of wells, were selected as decisive parameters for hydrogeological prioritization. The model pinpoints areas characterized by favorable hydrogeological conditions, which could be used for future development and implementation of an artificial storage and recovery (ASR) program. The designated priority areas for hydrogeological development occur at the southern, middle southern and some localized northern parts of the Darb el-Arbain area. The newly formed Tushka Lakes represent a suitable and excellent natural source of freshwater for implementing an ASR program. © 2010 Springer-Verlag. Source


Gameil M.,Cairo University | Gameil M.,King Abdulaziz University | Al Anbaawy M.,Cairo University | Abdel Fattah M.,Cairo University | Abu El-Kheir G.,Egyptian Environmental Affairs Agency EEAA
Journal of African Earth Sciences | Year: 2016

At Wadi Al Hitan area, rapid lateral and vertical variation is observed among the exposed middle and upper Eocene rock units. The tradionally known formations (Gehannam, Briket Qaroun, Qasr El-Sagha formations) interfinger laterally and not chronologically stacked above each other in most areas. Fine siltstones and claystones characterize the Gehannam Formation, sandstones and calcareous sandstones are characteristic for Briket Qaroun Formation, dark gray claystones are attributed to Garet El-Naqb Formation and interbedded claystones are attributed to Qasr El-Sagha Formation, irrespective of their stratigraphic position. Within these formations large numbers of marine vertebrate and invertebrate fossils exist at different stratigraphic levels. Whales are classified into four species belonging to four genera, these include Basilosaurus isis, Dorudon atrox, Saghacetus Osiris and Anclacetus simonsi. Basilosaurus isis and Dorudon atrox are the most common whale species exist in these formations. No major break in sedimentation has been described within the Eocene formations in Fayoum region. Only a well marked low sea stand is indicated at the top of the Gehannam Formation where it overlain by Birket Qaroun Formation. © 2015 Elsevier Ltd. Source


Elewa H.H.,National Authority for Remote Sensing and Space science | Qaddah A.A.,Egyptian Environmental Affairs Agency EEAA
Hydrogeology Journal | Year: 2011

Systematic planning for groundwater exploration using modern techniques is essential for the proper utilization, protection and management of this vital resource. Enhanced Thematic Mapper Plus (ETM+) images, a geographic information system (GIS), a watershed modeling system (WMS) and weighted spatial probability modeling (WSPM) were integrated to identify the groundwater potential areas in the Sinai Peninsula, Egypt. Eight pertinent thematic layers were built in a GIS and assigned appropriate rankings. Layers considered were: rainfall, net groundwater recharge, lithology or infiltration, lineament density, slope, drainage density, depth to groundwater, and water quality. All these themes were assigned weights according to their relative importance to groundwater potentiality and their corresponding normalized weights were obtained based on their effectiveness factors. The groundwater potentiality map was finally produced by WSPM. This map comprises five gradational groundwater potentiality classes ranging from very high to very low. The validity of this unbiased GIS-based model was tested by correlating its results with the published hydrogeological map of Egypt and the actual borehole yields, where a concordant justification was reached. The map declared that the Sinai Peninsula is generally of moderate groundwater potentiality, where this class encompasses an area of 33,120 km2 which represents 52% of its total area. © 2011 Springer-Verlag. Source


Elhefnawy E.I.,Egyptian Environmental Affairs Agency EEAA | Ali H.S.,Zagazig University | Mahmoud I.I.,Egypt Atomic Energy Authority
National Radio Science Conference, NRSC, Proceedings | Year: 2016

In this paper, an effective approach for dehazing and enhancing outdoor images is proposed. The dark channel prior is used to estimate a raw transmission map. This transmission map is then refined using guided image filtering under the guidance of the hazy image. For colors and details enhancement, the adaptive manifolds high-dimensional filtering is applied to the recovered scene radiance. The proposed approach is compared with other enhancement techniques and effective quality assessment methods are used for objective evaluation. The visual information fidelity (VIF) metric is used to quantify the loss of image information, since contrast overcompensation may cause information loss. The structural similarity index (SSIM) is used to quantify the degradation of structural information between the enhanced and recovered image. Other metrics including the ratio between the gradient of visible edges before and after enhancement are also computed. Experimental results show that combining guided image filtering for refining the raw transmission map, with adaptive manifolds filtering for image enhancement, produces images with improved colors, high contrast and minimum information loss. © 2016 IEEE. Source


Shama S.A.,Benha University | Moustafa M.E.,Benha University | Gad M.A.,Egyptian Environmental Affairs Agency EEAA
Portugaliae Electrochimica Acta | Year: 2010

The adsorption capacity of Eichhornia Crassipes towards metal ions such as Fe3+, Cu2+, Zn2+, Pb2+, Cr3+ and Cd2+, was studied. The adsorption capacity was investigated by batch experiments. The results showed that the removal percentages increased as the weight of sorbent increased, except for Fe3+ and Zn2+. The effect of contact time was also studied and the results showed that the removal percentages increased as the contact time increased for Cr3+, Zn2+ and Pb2+, but for Fe3+, Cu2+ and Cd2+ the removal decreased. The effect of pH of the solution was also studied and the removal percentages increased as pH increased. Also the effect of the initial concentration of metal ions was studied at four different concentrations (5, 10, 30, 50 mg/L); in case of metal ions (Cu2+, Zn2+ and Cd2+) the removal percentages increased by increasing initial concentration. But, for the other metal ions it decreased by increasing initial concentration over 30 mg/L. The order of increasing removal percentages of metal ions at pH=4.86, initial concentration of metal ions 30 mg/L, and after four hours of shaking was: Cu2+< Cr3+ Source

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