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Search Results: 1 - 10 of 26489 matches for " Mohammad El-Sayed "
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Effect of Urbanization and Industrialization Processes on Outdoor Thermal Human Comfort in Egypt  [PDF]
El-Sayed ROBAA
Atmospheric and Climate Sciences (ACS) , 2011, DOI: 10.4236/acs.2011.13012
Abstract: Detailed studies on the effect of urbanization and industrialization processes on outdoor thermal human com- fort in Greater Cairo region, Egypt have been performed in this study. Four different districts in Greater Cairo region have been selected to represent rural, suburban, typical urban and industrial areas. The data of surface dry, wet bulb temperatures and wind speed for two different periods represent non-urbanized and urbanized periods have been used. Discomfort indices for the two periods have been calculated for the four districts. The study revealed that urbanization and industrialization processes have resulted in the distinctly modification of human comfortable at all districts. The feeling of quite comfortable reduced from the old non-urbanized period to the recent urbanized period at the four districts. During the recent urbanized period, the rural area has the highest total number of quite comfortable hours while both urban and industrial areas have the lowest total number of hours. The serious hot uncomfortable didn’t occur at all districts during the old non-urbanized period while during the recent urbanized period, all people had felt extreme serious hot uncomfortable only at urban and industrial areas. It could be concluded that the urbanization and industriali-zation processes cause increase of human serious hot uncomfortable feeling which in turn leads to more hin-dering for the human activities while the rural conditions leads to optimum weather comfort for further and more human activities.
Advanced Transition/Cluster Key Management Scheme for End-System Multicast Protocol  [PDF]
Ayman El-Sayed
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2012, DOI: 10.4236/ijcns.2012.55038
Abstract: The recent growth of the World Wide Web has sparked new research into using the Internet for novel types of group communication, like multiparty videoconferencing and real-time streaming. Multicast has the potential to be very useful, but it suffers from many problems like security. To achieve secure multicast communications with the dynamic aspect of group applications due to free membership joins and leaves in addition to member's mobility, key management is one of the most critical problems. So far, a lot of multicast key management schemes have been proposed and most of them are centralized, which have the problem of \"one point failure\" and that the group controller is the bottleneck of the group. In order to solve these two problems, we propose a Key Management Scheme, using cluster-based End-System Multicast (ESM). The group management is between both 1) the main controller (MRP, Main Rendezvous Point) and the second controllers (CRP, Cluster RP), and 2) the second controllers (CRPs) and its members. So, ESM simplifies the implementation of group communication and is efficient ways to deliver a secure message to a group of recipients in a network as a practical alternative to overcome the difficulty of large scale deployment of traditional IP multicast. In this paper, we analyze different key management schemes and propose a new scheme, namely Advanced Transition/Cluster Key management Scheme (ATCKS) and find it has appropriate performance in security.
Use of the urinary trypsinogen-2 dipstick test in early diagnosis of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP)  [PDF]
Hasan El-Garem, Enas Hamdy, Sherif Hamdy, Mohammad El-Sayed, Aisha Elsharkawy, Azmi Mohammed Saleh
Open Journal of Gastroenterology (OJGas) , 2013, DOI: 10.4236/ojgas.2013.36049
Abstract: Background: Acute pancreatitis is one of the most serious complications of ERCP. Early diagnosis of post ERCP pancreatitis helps physicians to provide intensive care and possible medical treatment as early as possible. Trypsinogen-2 in urine is a good diagnostic and prognostic marker of acute pancreatitis. Objectives: To evaluate the diagnostic value of urinary trypsinogen-2 dipstick test for early diagnosis of post ERCP pancreatitis. Methods: A total of 37 patients with obstructive jaundice were tested with the urinary trypsinogen-2 dipstick test and serum levels of amylase and lipase before ERCP and 6 hours after ERCP. Results: Post ERCP pancreatitis was diagnosed in 6 (16%) of 37 patients. The sensitivity, specificity, positive predictive value and negative predictive value of urinary trypsinogen-2 dipstick test at 6 hours after ERCP were 100%, 97%, 86%, 100% respectively. At the cutoff level (130 U/L) for lipase, the positive predictive value and negative predictive value all were (100%), however, the positive predictive value and negative predictive value for amylase levels at cutoff (122 U/L) were 60%, 100% respectively. Serum lipase level was the best test for diagnosing post ERCP pancreatitis followed by the urinary trypsinogen-2 dipstick test. Conclusions: The urinary trypsinogen-2 dipstick test can be used as a rapid and easy test for early diagnosis of post ERCP pancreatitis with high sensitivity and specificity.
Performance Evaluation of One-Way Concrete Slabs Reinforced with New Developed GFRP Bars  [PDF]
Ahmed H. Ali, Mohammad Z. Afifi, Bahira Abdulsalam, Hesham Haggag, Awad El Hashimy, Tarek El-Sayed, Hamdy M. Mohamed
Materials Sciences and Applications (MSA) , 2015, DOI: 10.4236/msa.2015.65046
Abstract: The incorporation of fiber-reinforced-polymer (FRP) bars in construction as a replacement to steel bars provides a superior material which is capable to overcome corrosion problems. However, serviceability requirements are important issues to be considered in the design of concrete elements reinforced with glass-FRP (GFRP) bars which are known to have larger deflections and wider crack widths as well as weaker bond compared with steel reinforced concrete. As a solution to this problem, square GFRP bars are proposed. This paper presents the results of an experimental investigation that was performed, in which newly developed square and circular GFRP bars were fabricated in the lab. Also, the GFRP bars were tested and used to reinforce concrete slabs. A total of nine full-scale GFRP-reinforced concrete (RC) one-way slabs were constructed, tested and analyzed, considering the most influencing parameters such as the cross sectional shape of GFRP bars, reinforcement ratio, the concrete characteristics strength, and adding polypropylene fibers to the concrete mixture. The test results were showed that, the tested slabs with GFRP square bars improved the deflection and cracking behavior as well as the ultimate load.
Evaluation of the daily iron intake by non-breastfed Egyptian infants and young children.
AM El-Arab, M Mohammad, M El-Sayed
African Journal of Food, Agriculture, Nutrition and Development , 2009,
Abstract: Iron deficiency is frequently associated with anaemia. The prevalence of anaemia among Egyptian infants and young children is 25%. Fortification of infant and followup milk-based formulae remains a valuable method for delivering iron to reduce the incidence of iron deficiency anaemia. Percentage of Egyptian non-breastfed children consuming milk or milk products (7-23 months) are 79.1%. No studies have focused on infant and follow-up milk-based formulae that are marketed in Egypt regarding iron fortification and consumption. The objective of the current study was to evaluate the intake of iron by non-breastfed Egyptian infants and young children. To achieve this goal the infant and follow-up milk based formulae brands and types, low – iron and iron – fortified, that are commercially available on the local market were collected. In addition, the iron concentration was determined in the collected formulae in relation to the label statements to ensure the correct intake. Finally, the actual daily intake of iron from formulae consumption was estimated in relation to the nutritional requirements. The CRM 1846 and 3126a were used for the precision and accuracy of the method. It was shown that the iron levels in all milk-based formulae were lower than those reported on the labels and ranged between 6.17 -10.98 mg/L. No significant difference was found between the average concentration of iron in lowiron formula brands (8.1±2.3 mg/L) and iron-fortified formula brands (8.6± 2.0 mg/L). The average levels of the iron in the infant formula brands were lower (p<0.05) than follow-up formula brands. Iron- fortified infant brand (0-6 months) met the DRI for iron. However, low-iron brands had iron intake of 5.5, 5.3, 4.7 mg/day in the 4th month, 5th month, and 6th month, respectively, and were below the DRI. The Milk-based formula provided Egyptian infants (7-12 months) with only 30% and young children (12-23 months) with 40% from their daily iron requirement. Although the purpose of iron fortification was to assist infants and young children in increasing their iron intakes to help reduce iron-deficiency anaemia, the current level of fortification will not ensure that all infants and young children achieve recommended intakes of iron.
Selectivity of Acrylic Acid Radiation Grafted Non-Woven Polypropylene Sheets towards Some Heavy Metals Ions  [PDF]
Dalia El-Sayed Hegazy
Open Journal of Polymer Chemistry (OJPChem) , 2012, DOI: 10.4236/ojpchem.2012.21002
Abstract: Graft polymerization has been considered as a general method for the modification of the physical and chemical properties of polymeric materials and of particular interest for synthesis of the hydrophilic membrane. In this study, hydrophilic carboxylic acid groups were introduced by radiation-induced grafting of acrylic acid (AAc) onto non-woven polypropylene fabric (NWPP). Different irradiation doses and (AAc) monomer concentrations were used to optimize grafting yield. Characterization and properties of the prepared graft copolymer were studied by employing X-ray Dif-fraction (XRD), Thermogravimetric Analysis (TGA), Scanning Electron Microscope (SEM ), Fourier Transform Infrared Spectrometry (FTIR) and differential scanning calorimeter (DSC). The prepared grafted materials were used for removing some heavy metals ions. The results showed that the non-woven PP grafted with (AAc) has good affinity toward Cu, Ni and Co.
Detection of Land-Use and Surface Temperature Change at Different Resolutions  [PDF]
El-Sayed Ewis Omran
Journal of Geographic Information System (JGIS) , 2012, DOI: 10.4236/jgis.2012.43024
Abstract: Understanding the relationship between land-use/land-cover change (LULCC) and environment is seriously important to manage arid land. However, information on how environmental factors influence the LULCC patterns at different scales in arid area is lacking. This paper investigates the application of RS/GIS for detecting LULCC and assessing its impact on surface temperature in the Ismailia Governorate, Egypt. Landsat images have been utilized to quantify the changes from 1984 to 2011. The images were pre-processed using calibration techniques and the geometric and atmos- pheric corrections were performed. Different ratios, indices, and optimized index factor were implemented to decide the best band combination. Supervised classification using Maximum Likelihood technique and spatial reclassification have been employed. Six land-use/land-cover categories (urban, vegetation, waterlogged 1 and 2, bare land, and water) were identified. The highest overall accuracy and Kappa coefficient is 93.04% and 80.65%, respectively. The integration of RS and GIS was further applied to examine the impact of land-use change on surface temperatures. The results revealed a notable land-use change in the study area. The Built-up area has rapidly increased in Ismailia during the 27 years pe- riod. The built-up area (37.65?C in 1984 and 43.876?C in 2011) and Barren land (37.34?C in 1984 and 42.801?C in 2011) exhibit the highest surface radiant temperature, while vegetated surfaces (28.73?C in 1984 and 32.96?C in 2011), water (25.94?C in 1984 and 27.32?C in 2011), waterlogged1 (34.54?C in 1984 and 35.60?C in 2011) recorded low radiant temperature respectively. Waterlogged2 is the class that shows an unexpected radiant temperature (26.38?C in 1984 and 27.75?C in 2011). The urban development between 1984 and 2011 has given rise to an average of 6.23?C in surface radiant temperature. During 27 years, the change rate of land-use types which are decreased are barren land (1.12% an- nually) and waterlogged1 and 2 (0.76 and 6.61% annually). The area of vegetation, water, and built-up are increased by 0.98%, 0.82%, and 0.61% per year, respectively.
Improving the Prediction Accuracy of Soil Mapping through Geostatistics  [PDF]
El-Sayed Ewis Omran
International Journal of Geosciences (IJG) , 2012, DOI: 10.4236/ijg.2012.33058
Abstract: This research aimed to implement and compare the accuracy of different interpolation methods using cross validation errors for interpolating the spatial pattern of soil properties. This paper investigates whether the use of kriging, instead of traditional interpolation methods, improves the accuracy of prediction of soil properties. To this end, various interpolation (kriging) techniques that rely on the spatial correlation between observations to predict attribute values at ensampled locations are studied. Geostatistics provides descriptive tools such as semivariograms to characterize the spatial pattern of continuous and categorical soil attributes. The maps obtained from Ordinary Kriging, Inverse Distance Weighting and splines show clearly that the map from Universal Kriging (UK) is better than the other three interpolation methods. Therefore, UK can be considered as an accurate method for interpolating soil (EC, pH, CaCO3) properties.
The Products of Regularly Solvable Operators with Their Spectra in Direct Sum Spaces  [PDF]
Sobhy El-Sayed Ibrahim
Advances in Pure Mathematics (APM) , 2013, DOI: 10.4236/apm.2013.34060
Abstract:

In this paper, we consider the general quasi-differential expressions \"\" each of order n with complex coefficients and their formal adjoints on the interval (a,b). It is shown in direct sum spaces \"\" of functions defined on each of the separate intervals with the cases of one and two singular end-points and when all solutions of the equation \"\" and its adjoint \"\" are in \"\" (the limit circle case) that all well-posed extensions of the minimal operator \"\" have resolvents which are HilbertSchmidt integral operators and consequently have a wholly discrete spectrum. This implies that all the regularly solvable operators have all the standard essential spectra to be empty. These results extend those of formally symmetric expression \"\" studied in [1-10] and those of general quasi-differential expressions

Attitude Control of an Axi-Symmetric Rigid Body Using Two Controls without Angular Velocity Measurements Paper  [PDF]
Tawfik El-Sayed Tawfik
World Journal of Mechanics (WJM) , 2013, DOI: 10.4236/wjm.2013.35A001
Abstract:

This paper considers the problem of controlling the rotational motion of an axi-symmetric rigid body using two independent control torques without angular velocity measurements. The control law which stabilizes asymptotically this motion is obtained only in terms of the orientation parameters. Global asymptotic stability is shown by applying LaSalle invariance principal. Numerical simulation is introduced.

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