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Hydrogen Production from an Alkali Electrolyzer Operating with Egypt Natural Resources  [PDF]
Mohamed H. Shedid, S. Elshokary
Smart Grid and Renewable Energy (SGRE) , 2015, DOI: 10.4236/sgre.2015.61002
Abstract: Egypt is bordered by coastal sea2450 km, while incident solar radiation is in the order of magnitudes of 1900-2200 W/m2 in that area of the world. The present work is aimed to assess the hydrogen production from the solar-hydrogen system composed of photovoltaic cell motivated by solar energy and supplies electricity to alkali electrolyzer. The electrolyzer uses sea and Nile water as electrolytes. Indoor tests are done to identify the optimum concentration ratio of the sea water to produce hydrogen. Experimental results showed that stand-alone sea water gives a higher production rate. The results of the outdoor tests revealed the need for about seven units of electrolyzer working with the sea water to produce the same amount of hydrogen that KOH solution electrolyte would provide. However, the efficiency of solar-hydrogen units working with the sea water gives a lower constant efficiency of about 0.13%, followed by Photovoltaic/electrolyzer unit using Nile water of approximately 0.005%. The KOH solution electrolyte provides an efficiency of approximately 8% at solar noon. The sea water is recommended to be used instead of KOH solution in all coming electrolyzers.
Tracking Individual Targets in High Density Crowd Scenes Analysis of a Video Recording in Hajj 2009  [PDF]
Mohamed H. Dridi
Current Urban Studies (CUS) , 2015, DOI: 10.4236/cus.2015.31005
Abstract: In this paper we present a number of methods (manual, semi-automatic and automatic) for tracking individual targets in high density crowd scenes where thousands of people are gathered. The necessary data about the motion of individuals and a lot of other physical information can be extracted from consecutive image sequences in different ways, including optical flow and block motion estimation. One of the famous methods for tracking moving objects is the block matching method. This way to estimate subject motion requires the specification of a comparison window which determines the scale of the estimate. In this work we present a real-time method for pedestrian recognition and tracking in sequences of high resolution images obtained by a stationary (high definition) camera located in different places on the Haram mosque in Mecca. The objective is to estimate pedestrian velocities as a function of the local density. The resulting data of tracking moving pedestrians based on video sequences are presented in the following section. Through the evaluated system the spatiotemporal coordinates of each pedestrian during the Tawaf ritual are established. The pilgrim velocities as function of the local densities in the Mataf area (Haram Mosque Mecca) are illustrated and very precisely documented. Tracking in such places where pedestrian density reaches 7 to 8 persons/m2 is extremely challenging due to the small number of pixels on the target, appearance ambiguity resulting from the dense packing, and severe inter-object occlusions. The tracking method which is outlined in this paper overcomes these challenges by using a virtual camera which is matched in position, rotation and focal length to the original camera in such a way that the features of the 3D-model match the feature position of the filmed mosque. In this model an individual feature has to be identified by eye, where contrast is a criterion. We do know that the pilgrims walk on a plane, and after matching the camera we also have the height of the plane in 3D-space from our 3D-model. A point object is placed at the position of a selected pedestrian. During the animation we set multiple animation-keys (approximately every 25 to 50 frames which equals 1 to 2 seconds) for the position, such that the position of the point and the pedestrian overlay nearly at every time. By combining all these variables with the available appearance information, we are able to track individual targets in high density crowds.
Pedestrian Flow Simulation Validation and Verification Techniques  [PDF]
Mohamed H. Dridi
Current Urban Studies (CUS) , 2015, DOI: 10.4236/cus.2015.32011
Abstract: For the verification and validation of microscopic simulation models of pedestrian flow, we have performed experiments for different kind of facilities and sites where most conflicts and congestion happens e.g. corridors, narrow passages, and crosswalks. The validity of the model should compare the experimental conditions and simulation results with video recording carried out in the same condition like in real life e.g. pedestrian flux and density distributions. The strategy in this technique is to achieve a certain amount of accuracy required in the simulation model. This method is good at detecting the critical points in the pedestrians walking areas. For the calibration of suitable models we use the results obtained from analysing the video recordings in Hajj 2009 and these results can be used to check the design sections of pedestrian facilities and exits. As practical examples, we present the simulation of pilgrim streams on the Jamarat bridge (see Figure 5). The objectives of this study are twofold: first, to show through verification and validation that simulation tools can be used to reproduce realistic scenarios, and second, gather data for accurate predictions for designers and decision makers.
Simulation of High Density Pedestrian Flow: A Microscopic Model  [PDF]
Mohamed H. Dridi
Open Journal of Modelling and Simulation (OJMSi) , 2015, DOI: 10.4236/ojmsi.2015.33009
Abstract: In recent years, modelling crowd and evacuation dynamics has become very important, with increasing huge numbers of people gathering around the world for many reasons and events. The fact that our global population grows dramatically every year and the current public transport systems are able to transport large amounts of people heightens the risk of crowd panic or crush. Pedestrian models are based on macroscopic or microscopic behaviour. In this paper, we are interested in developing models that can be used for evacuation control strategies. This model will be based on microscopic pedestrian simulation models, and its evolution and design requires a lot of information and data. The people stream will be simulated, based on mathematical models derived from empirical data about pedestrian flows. This model is developed from image data bases, so called empirical data, taken from a video camera or data obtained using human detectors. We consider the individuals as autonomous particles interacting through social and physical forces, which is an approach that has been used to simulate crowd behaviour. The target of this work is to describe a comprehensive approach to model a huge number of pedestrians and to simulate high density crowd behaviour in overcrowding places, e.g. sport, concert and pilgrimage places, and to assist engineering in the resolution of complicated problems through integrating a number of models from different research domains.
Effect of Heat Treatment Parameters on the Mechanical and Microstructure Properties of Low-Alloy Steel  [PDF]
Mohamed H. Frihat
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2015, DOI: 10.4236/jsemat.2015.54023
Abstract: This study examines the effect of heat treatment at three different temperatures of 800°C, 950°C and 1100°C on the microstructure and mechanical properties of low-alloy steel with an addition of manganese, chrome and lead. To determine an impact of the applied heat treatment operations, testing of mechanical properties and microstructural examinations of the steel with 0.23%, 0.24%, 0.29% and 0.31% C were conducted. This work shows that the mechanical strengths of the alloy steel are improved with increasing the heat treatment temperature. In addition, the microstructure trends toward recrystallized ferrite grains as the heat treatment temperature increases.
Pharmacist Role in Pharmaceutical Care during Ramadan  [PDF]
Osama H. Mohamed Ibrahim
Pharmacology & Pharmacy (PP) , 2015, DOI: 10.4236/pp.2015.612061
Abstract: Introduction: Ramadan is the ninth month in the Islamic Hijri calendar where Muslims are ex-pected to fast every day from dawn to sunset. The eating behavior changes during Ramadan and the abstinence of food affects the oral drugs administration and other convenience dosage forms. There is a need to highlight and illustrate the role of the pharmacists in medication adjustment challenges that the patients conquer in the Holy month of Ramadan. Objectives: To estimate the awareness of pharmacists’ role in providing pharmaceutical care during Ramadan; moreover, to explore pharmacists’ perspective on the importance of medication regimen adjustment along with the proper counseling required to optimize patients’ health throughout fasting. Method: This is an observational study that was done through dissemination of a cross-sectional survey among 130 pharmacists covering Abu Dhabi, Dubai, Sharjah, Ajman, and Northern Emirates regions. The targeted population consisted of practicing community pharmacists and hospital pharmacists across UAE. Results: Among pharmacists participated in the study 115 pharmacists (88.5%) were Muslims and 79 pharmacists (60.8%) were Arabs. 126 pharmacists (97%) reported performing one or more kinds of medication regimen adjustment around Ramadan for at least one patient. Changing the frequency had the highest percentage by the pharmacist compared to other methods of regimen adjustment (39%). Moreover, the results revealed that 46.9% of the pharmacists chose not to change the medication itself. Nineteen percent of Muslim pharmacists initiated the conversation about medication regimen adjustment (P = 0.0448) compared to non-Muslims, while14% of pharmacists were Arabs who showed no statistically significant difference. Conclusion: In conclusion, pharmacists are more qualified to adjust and manage medication regimens than what they are presently performing. Utilization of such skill is required to adjust patients’ medication regimen during fasting the Holy month of Ramadan and to ensure safe transition for fasting patients into and out of Ramadan.
Numerical Solution for the Fractional Wave Equation Using Pseudo-Spectral Method Based on the Generalized Laguerre Polynomials  [PDF]
Nasser H. Sweilam, Mohamed M. Khader, Mohamed Adel
Applied Mathematics (AM) , 2015, DOI: 10.4236/am.2015.64058
Abstract: In this paper, an efficient numerical method is considered for solving the fractional wave equation (FWE). The fractional derivative is described in the Caputo sense. The method is based on Laguerre approximations. The properties of Laguerre polynomials are utilized to reduce FWE to a system of ordinary differential equations, which is solved by the finite difference method. An approximate formula of the fractional derivative is given. Special attention is given to study the convergence analysis and estimate an error upper bound of the presented formula. Numerical solutions of FWE are given and the results are compared with the exact solution.
Validity of Upper Gastro-Intestinal Endoscopic Screening in HCV Cirrhotic Patients Awaiting Antiviral Therapy  [PDF]
Salem Y. Mohamed, Bassim A. Gaballah, Mohamed H. Emara
Open Journal of Gastroenterology (OJGas) , 2015, DOI: 10.4236/ojgas.2015.512029
Abstract: Background and Aim: The Egyptian Ministry of Health initiated a nationwide HCV treatment program with the newly developed oral antiviral therapies and formulated national guidelines for treatment allocation which gave favor for patients with advanced fibrosis and early cirrhosis. One of the recommendations for treatment was upper Gastro-intestinal (GIT) endoscopy. This study aimed at estimating the prevalence of varices among those patients and judging the validity of this national recommendation. Methods: This study was carried out at gastrointestinal endoscopy units, Zagazig University Hospitals through the year 2014. The epidemiologic, clinical features and endoscopic findings of patients undergoing preparation for HCV therapy were analyzed. Endoscopic classifications of esophageal and gastric varices were carried out after the Italian liver cirrhosis project and Sarin’s classification respectively. Results: Totally 1143 patients performed upper GIT endoscopy as preparation for HCV treatment. This comprised 22% of all patients undergoing upper GIT endoscopy over that year. There was a fourfold rise in percentage of patients undergoing endoscopy for sofosbuvir-based therapy in this year (22%) when compared to assessment for Interferon/Ribavirin combination therapy (5%) in the previous year. A total of 361 patients had no esophageal or gastric varices. Small sized (grade I), medium sized (grade II) and large sized (grade III) varices were reported in 301, 188 and 293 patients respectively. Thirty patients (2.6%) had gastric varices. The prevalence of varices was higher in Child B in comparison to Child A (statistically not significant, p = 0.243). Conclusion: Screening endoscopy for early cirrhotic patients awaiting oral anti-HCV therapy is valid.
Experimental and Numerical Investigation of Desalination Plant Outfalls in Limited Disposal Areas  [PDF]
Mohamed E. Abou-Elhaggag, Mohamed H. El-Gamal, Mohamed I. Farouk
Journal of Environmental Protection (JEP) , 2011, DOI: 10.4236/jep.2011.26094
Abstract: In this study, experimental and numerical investigations of the dense brine jets are conducted for disposal areas of limited extent. First, a new experimental model representing a section of sea floor with a single port brine outfall is built to study different characteristics of dense jets. Second, a number of numerical experiments have been conducted via Fluent CFD package to compare the numerical results with its corresponding physical observations and measurements. Experimental observations are made for both the terminal height of rise of dense jets discharged vertically from circular outlets into calm and homogeneous environment and for concentration profiles along the dense jet trajectory. Various combinations of port diameters and concentration of effluent salinities are investigated to cover a wide range of conditions. The results from the carried out experiments are compared to different available experimental and field observations from the literature. A new model for the terminal height of rise of dense jets has been derived. The experimental observations of concentrations along the dense jet trajectory are analyzed to quantify the mixing patterns for a given operating condition from the source point to the terminal height of rise. The numerical model has been used to identify the penetration depth and also to get the temporal variation of the brine breakthrough curves at different locations above the disposal port. The numerical model has shown the existence of multipeak breakthrough curves for the farest points from the port (but the closest to the water free surface).
Haemato-biochemical and pathological studies on aflatoxicosis and treatment of broiler chicks in Egypt
Mohamed A. Hashem,Mohamed H. Mohamed
Veterinaria Italiana , 2009,
Abstract: The aim of this study was to evaluate the prophylactic efficacy of protexin (probiotic), inulin (prebiotic) and both (synbiotics), when included in a diet containing aflatoxins and fed to growing broiler chicks (from 1 to 21 days old). The criteria of the evaluation included body weight gain, haematological profile and biochemistry, in addition to associated lesions in chicks. A total of 160 Hubbard male day-old broiler chicks were separated into eight groups that all received different diets (additional aflatoxins, protexin, inulin and symbiotic). The birds were weighed and sacrificed at the age of 21 days. Compared to the controls, aflatoxins alone significantly (p<0.05) decreased body weight gain in one group. No difference in body weight gain was found in three groups, indicating apparent protection against the deleterious effects caused by aflatoxins. The weight gain of chicks fed on the diet containing synbiotics alone or synbiotics and aflatoxins was significantly (p<0.05) greater than that of chicks on a diet containing the other treatments. The birds the second group showed significant (p<0.05) reduction in the haematological parameters in comparison with the controls. The biochemical analysis showed a considerable (p<0.05) increase in the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), uric acid and creatinine levels, with a reduction in the serum total proteins, albumin and globulins. The addition of protexin, inulin, or both, diminished the adverse effects of aflatoxins. Finally, it was concluded that the protexin, inulin and synergism of both are effective in the amelioration of the toxic effects of aflatoxins that may be present in poultry rations at levels up to 4 mg/kg diet. Synbiotics (protexin and inulin) are more effective than the protexin and the inulin alone which are variable in the alleviation of toxic effects caused by aflatoxins.
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