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Search Results: 1 - 10 of 503156 matches for " M. K. El Fawkhry "
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Feasibility of new ladle-treated Hadfield steel for mining purposes
M. K. El Fawkhry
- , 2018, DOI: https://doi.org/10.1007/s12613-018-1573-z
Abstract: A debate has arisen over the possibility of using a new ladle-treated Hadfield steel instead of conventional heat-treated Hadfield steel in mining applications. This debate might be solved by identifying the differences between the mechanical properties and strain-hardening properties of conventional heat-treated Hadfield steel and its counterpart ladle-treated Hadfield steel. Tensile and compression tests demonstrated that the ductility of ladle-treated Hadfield steel is similar to that of conventional heat-treated steel. However, the strain-hardening property of the ladle-treated Hadfield steel is almost two times higher than that of the heat-treated Hadfield steel. The results of this study demonstrate that the improvement of the strain-hardening behavior is attributable to the low stacking-fault energy of the main austenite matrix, which results from the high segregation coefficient of carbon and manganese solutes of the main austenite matrix into the new eutectic phase. Superior wear abrasion resistance is a potential consequence of different strain-hardening properties under low and high loads.
Prediction of Symmetrical and Asymmetrical of Diurnal Global Solar Irradiance Distribution—New Approach  [PDF]
M. K. El-Adawi
Optics and Photonics Journal (OPJ) , 2019, DOI: 10.4236/opj.2019.92003
Abstract: A simple formula to predict the received global solar irradiance q(t), W/m2 for clear days is suggested on pure theoretical basis. It is expressed in terms of the length of the local day time td which is well defined in literatures on meteorological basis. The introduced distribution is also a function of the maximum value of the daily received irradiance qmax. which in turn is expressed in term of the solar constant. This renders the trial to be a closed system. Thus the obtained distribution is not a semi empirical one. Both cases of symmetrical and asymmetrical distributions for q(t) are considered. For its simplicity it can be easily integrated along the length of the day to get the daily totals of solar energy received by unit horizontal area. This is important for practical applications. Comparison between computed according to the present model and published experimental meteorological data in Barcelona (Spain), Hong Kong (China), Jeddah and Makkah (Saudi Arabia) is given as illustrative examples. Better fitting relative to the published trials for the same locations are obtained. The introduced model itself gives good fitting for the intermediate intervals points of the local day time which is the more effective region. The estimated relative error is 12% for Hong Kong, and it is 7% for Barcelona, Jeddah and Makah.
Sentinel-1 Radar Data Assessment to Estimate Crop Water Stress  [PDF]
M. A. El-Shirbeny, K. Abutaleb
World Journal of Engineering and Technology (WJET) , 2017, DOI: 10.4236/wjet.2017.52B006
Abstract:
Water is an important component in agricultural production for both yield quantity and quality. Although all weather conditions are driving factors in the agricultural sector, the precipitation in rainfed agriculture is the most limiting weather parameter. Water deficit may occur continuously over the total growing period or during any particular growth stage of the crop. Optical remote sensing is very useful but, in cloudy days it becomes useless. Radar penetrates the cloud and collects information through the backscattering data. Normalized Difference Vegetation Index (NDVI) was extracted from Landsat 8 satellite data and used to calculate Crop Coefficient (Kc). The FAO-Penman-Monteith equation was used to calculate reference evapotranspiration (ETo). NDVI and Land Surface Temperature (LST) were calculated from satellite data and integrated with air temperature measurements to estimate Crop Water Stress Index (CWSI). Then, both CWSI and potential crop evapotranspiration (ETc) were used to calculate actual evapotranspiration (ETa). Sentinel-1 radar data were calibrated using SNAP software. The relation between backscattering (dB) and CWSI was an inverse relationship and R2 was as high as 0.82.
Saidiye Hanl ve Hocalar Devri Kaynaklar (1514-1762)////Sources of the Khanate of Saidiya and the Khojas Period (1514-1762)
M. Bilal ?ELK
History Studies : International Journal of History , 2012,
Abstract: This study introduces the main historical sources relating to the region variously referred as East Turkestan, Little Bukhara, Kashgar, Sixth Cities, Tarim Basin, Chinese Turkestan and Sinkiang. After the rule of Khanate of Saidiya between 1514 and 1696, the members of Naqshbandi Order known as Khojas ruled this region until Chinese rule was established in 1762. During this period there was not a powerful and successful rule in East Turkestan but there was still a central administration. A close examination of the Khanate of Saidiya and the Khojas reveals that there are noticeably large numbers of understudied sources about this period. This work aims to introduce these unexamined sources.
Oil and Gas Prospects in Egypt Recherches d'huile et de gaz en égypte
El Ayouti M. K.
Oil & Gas Science and Technology , 2006, DOI: 10.2516/ogst:1980010
Abstract: Accumulations of oil were first known in Egypt since 1968, some ten years after the famous Drake well in Pennsylvania in August 1859. These oil accumulation were found as seepages in tunnels dug for extracting sulphur in the area of Gemsa on the West coast of the Gulf of Suez. Since that time exploration activites were conducted on and off throughout a long history of operations which witnessed the use of the latest developments in exploration tools and techniques. So far, the main oil province in Egypt is the Gulf of Suez Basin, where the bulk of oil reserve have been found. Other hydrocarbon provinces are the Nile Delta Basin, the Abu Gharadig Basin and the Alamein ridge, both in the Western Desert. Three important gas discoveries were made in the Nile Delta Basin two of which are offshore, in addition to other so for non commercial gas finds. In addition to the known oil and gas discoveries the exploration activities throughout that long period contributed volumenous geological and geophysical material and data which added appreciably to the geology of Egypt at large, and in particular to the petroleum geology of the country. The Gulf of Suez oil province displayed very favourable conditions for the generation and trapping of hydrocarbons in Miocene and Pre-Miocene pools though at the same time it displayed very complicated geological setting which renders the exploration work a difficult task. The Nile Delta Basin, on the otherhand, is a relatively very recently explored area. Accordingly, extensive exploration work is still needed in order to evaluate the hydrocarbon possibilities of that basin. So for, gas has been discovered at a number of locations in lower Pliocene-Miocene pools. Whether future work would prove that oil generation took place remains to be seen. The Western Desert did not yet display the required response with regards to the exploration work conducted till now. To date, only few small discoveries have been made with oil and gas pools mainly vvithin the Upper and Lower Cretaceous. Recent advances in seismic techniques are helping in locating deeper structures, which might prove instrumental in the upgrading of the oil possibilites of the region. At present, the exploration activities are going on in the different oil and gas provinces in Egypt. These activilles are expected to increase and are also expected to expand to new areas in the eastern part of the Gulf of Suez Basin, offshore and onland, in Northern Sinai and in the Offshore Mediterranean. These new areas are believed to house very good prospects which will be tested not
Exponential Spline Solution for Singularly Perturbed Boundary Value Problems with an Uncertain—But—Bounded Parameter  [PDF]
W. K. Zahra, M. A. El-Beltagy, A. M. El Mhlawy, R. R. Elkhadrawy
Journal of Applied Mathematics and Physics (JAMP) , 2018, DOI: 10.4236/jamp.2018.64073
Abstract: In this paper, we develop a new numerical method which is based on an exponential spline and Shishkin mesh discretization to solve singularly perturbed boundary value problems, which contain a small uncertain perturbation parameter. The proposed method uses interval analysis principle to deal with the uncertain parameter and the Monte Carlo Simulations (MCS) are used to validate the solution and the accuracy of the proposed method. Furthermore, sensitivity analysis has been conducted using different methods to assess how much the solution is sensitive to the changes of the perturbation parameter. Numerical results are provided to show the applicability and efficiency of the proposed method, which is ε-uniform convergence of almost second order.
GIS Data Integration to Manage Waterlogging Problem on the Eastern Nile Delta of Egypt  [PDF]
M. F. Kaiser, A. El Rayes, K. Ghodeif, B. Geriesh
International Journal of Geosciences (IJG) , 2013, DOI: 10.4236/ijg.2013.44063
Abstract:

Three sets of satellite data were utilized to outline and monitor the waterlogging problems along the Wadi El Tumilate basin. These data include Thematic Mapper image for year 1984, Enhanced Landsat Thematic Mapper image for year 2000 and SPOT-4 image for year 2008. Supervised classification using the maximum likelihood approach has been performed. A number of 6 classes were observed at the study sites including, Niledeposits and cultivated areas, surface water and water logged areas, salt crust, Quaternary playa deposits, fluviatile and lacustrine deposits and Miocene (gypsum and carbonate) deposits. Water logged areas expanded from9.1 km2 inyear 1984 to18.8 km2 inyear 2000 to25.3 km2 inyear 2008, with a rate of0.7 km2/year. At the same time, vegetation cover shows an increase from453 km2 inyear 1984 to719 km2 inyear 2008. The integrated data used by Geographic Information Systems specified factors controlling waterlogging problems, which are: topography, drainage pattern and water flow direction, excess of irrigation water, deficiency of drainage system, presence of impermeable clay lenses and lineaments direction. Groundwater modeling including GMS and MODFLOW programs were processed to manage waterlogging problem. Using of underground tile drain along the eastern portion of Wadi El Tumilate basin and dewatering wells along the western side was recommended to obtain the highest monetary return from the drainage investment.

Nocturia: Impact on quality of life in an Egyptian adult population  [PDF]
Salma M. S. El Said, Tomader Abd El Rahman, Ahmed K. Mortagy, Marian Wagieh Mansour
Advances in Aging Research (AAR) , 2013, DOI: 10.4236/aar.2013.24023
Abstract:

OBJECTIVE: To estimate the effects of nocturia on quality of life (QoL) and to assess the associated effects of sleep problems. Background: Nocturnal urination (nocturia) is such a commonplace occurrence in the lives of many older adults that it is frequently overlooked as a potential cause of sleep disturbance. Methods: The current study was carried out to assess the prevalence of nocturia in elderly males and its impact on sleep quality and QoL. The study enrolled 200 elderly males aged 60 years old and above. All participants were recruited from geriatric clubs in Cairo. All participants in the study were subjected to: comprehensive geriatric assessment, American Urological Association (AUA) score used to measure the severity of nocturia ,assessment of sleep quality using Pittsburgh Sleep Quality Index (PSQI) and assessment of QoL using “SF-12 Short Form Health Survey”. Results: The study showed that the prevalence of nocturia in elderly males aged ≥60 years old was 68% with significant association between nocturia and diabetes mellitus, heart failure, stroke, prostatism, recurrent UTI and diuretic use. As regard sleep quality, the current study showed that the prevalence of
poor sleep in the studied subjects is 70.5% with significant association between nocturia and poor sleep quality. Nocturia significantly affects sleep latency, sleep efficiency and daytime dysfunction, high significantly affecting sleep disturbance. Also diabetes mellitus, ischemic heart disease, heart failure, prostatism, recurrent UTI, osteoarthritis and diuretic use are significantly associated with poor sleep quality. As regard quality of life, the current study showed significant association between nocturia and physical and mental health components of HRQL in the univariate analysis. But after multivariate analysis, nocturia is not an independent risk factor for poor quality of life. Nocturia affects QoL through its effect on sleep quality which is an independent risk factor for poor physical and mental health components of QoL. Conclusion: Nocturia may lead to sleep insufficiency and consequently to a decrease in mental and physical health. Patients who consult a doctor for nocturia should thus be treated adequately. In addition, it is worthwhile for doctors to routinely check if patients’ who contact them for sleep problems also have nocturia.

A Modified Interactive Stability Algorithm for Solving Multi-Objective NLP Problems with Fuzzy Parameters in Its Objective Functions  [PDF]
Mohamed Abd El-Hady Kassem, Ahmad M. K. Tarabia, Noha Mohamed El-Badry
American Journal of Operations Research (AJOR) , 2016, DOI: 10.4236/ajor.2016.61002
Abstract:

This paper presents a modified method to solve multi-objective nonlinear programming problems with fuzzy parameters in its objective functions and these fuzzy parameters are characterized by fuzzy numbers. The modified method is based on normalized trade-off weights. The obtained stability set corresponding to α-Pareto optimal solution, using our method, is investigated. Moreover, an algorithm for obtaining any subset of the parametric space which has the same corresponding α-Pareto optimal solution is presented. Finally, a numerical example to illustrate our method is also given.

The Potential Role of Cu2+ and Combined Action with IAA on Tolerance Strategy of Two Broad Bean Cultivars  [PDF]
Hamdia M. Abd El-Samad, Mohamed Abdo K. Shaddad, Kholoud N. Abd El-Hakeem
American Journal of Plant Sciences (AJPS) , 2018, DOI: 10.4236/ajps.2018.910153
Abstract: The present work was conducting to study the strategy response of two broad bean cultivars Assiut 84 and Assiut 125 to different Cu2+ concentrations 100 ppm, 200 ppm, 300 ppm and 350 ppm in addition to control and interactions with IAA treatments. The dry matter exhibited the biphasic effect of Cu2+ on the growth criteria of the two broad bean cultivars. While the lower and moderate doses of Cu2+ (100 ppm and 200 ppm) stimulated the growth of the two cultivars, the higher doses revealed the opposite event where the growth dropped in both cultivars. This effect was more pronounced in cv. Assiut 84 than in cv. Assiut 125 and also at the higher Cu2+ concentration the growth dropped slightly in cv. Assiut 84 and highly significantly in cv. Assiut 125. The percent of increase in dry matter at 200 ppm in stem and leaf of cv. Assiut 84 was 120.45% and 155.31%, otherwise this percent of increase in these organs of cv. Assiut 125 was 114.29% and 131.41%. However the percent of reduction at 350 ppm Cu2+ in root and stem of cv. Assiut 84 was 74.13%, 79.23% and in root, stem and leaf of cv. Assiut 125 was 59.27%, 70.91%, 70.76% compared with control plants. Soluble carbohydrate in cv. Assiut 84 and cv. Assiut 125 was markedly increased while soluble protein was decreased in root, stem and in leaves at lower Cu2+ concentration.
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