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Utilization of Egyptian Ilmenite Ore for Steel Surface Preparation in Petroleum Field

Engineering（科研） 2011年第8期3卷 802-809页

作者： Mahmoud Ibrahim abdou mohamed abd el-Fattah Moustafa Hany el- Sayed Ahmed Hamada abd el-Wahab Production Department Egyptian Petroleum Research Institute (EPRI) Cairo Egypt

The construction of gas and oil plants include many items such as steel structures, equipments, piping, tanks and vessels at different conditions such as offshore, onshore, above and underground shall be protected against corrosion by coating. The protective value of a coating system is proportional to the surface preparation;the objectives of the surface preparation are the surface cleanliness and the surface profile of the substrate. The surface preparation is usually achieved by blast cleaning using different types of abrasive. Due to its high hardness and low cost, silica sand has been used extensively for impact abrasion. It is, however, very brittle with most grain disintegrating on impact, causing excessive levels of siliceous dust which is a major health hazard and causes serious environmental pollution. Consequently, it has been banned as impact abrasive material in most countries around the world. Considerable research has been done in the last twenty years to find an impact abrasive material as hard as silica and that respects. So it was important to search for sand substitution among the local abundant minerals in Egypt. Waste product obtained from ilmenite ore extracted from the mine was found to be the most suitable alternative abrasive. This work shows the abrasive types, the occurrence of the ilmenite ore. The chemical properties, physical properties and microscopic examination of the waste were investigated. The obtained result indicates that, the waste product obtained from ilmenite ore can be utilized for abrasion as sand substitution.

关键词： Blast Cleaning Material Ilmenite Abrasive Material Surface Cleanliness Surface Profile and Surface Preparation.

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Blind Modulation Recognition in Wireless MC-CDMA Systems Using a Support Vector Machine Classifier

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Wireless Engineering and Technology 2013年第3期4卷 145-153页

作者： mohamed el-Hady Magdy Keshk Keshk el-Sayed elrabie Fathi el-Sayed abd el-Samie Mohammed abd el-Naby Egyptian Space Program National Authority for Remote Sensing and Space Science Cairo Egypt Faculty of electronic Engineering Menoufia University Menouf Egypt.

Automatic Digital Modulation Recognition (ADMR) is becoming an interesting problem with various civil and military applications. In this paper, an ADMR algorithm in Multi-Carrier Code Division Multiple Access (MC-CDMA) systems using Discrete Transforms (DTs) and Mel-Frequency Cepstral Coefficients (MFCCs) is proposed. This algorithm uses various DT techniques such as the Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT) and Discrete Sine Transform (DST) with MFCCs to extract features from the modulated signal and a Support Vector Machine (SVM) to classify the modulation orders. The proposed algorithm avoids over fitting and local optimal problems that appear in Artificial Neural Networks (ANNs). Simulation results shows the classifier is capable of recognizing the modulation scheme with high accuracy up to 90% - 100% using DWT, DCT and DST for some modulation schemes over a wide Signal-to-Noise Ratio (SNR) range in the presence of Additive White Gaussian Noise (AWGN) and Rayleigh fading channel, particularly at a low Signal-to-Noise ratios (SNRs).

关键词： ADMR MC-CDMA MFCC DT SVM ANN

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Prevalence of Cerebral Atherosclerosis among Patients with Metabolic Syndrome: A Case Control Study on Egyptian Subjects

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World Journal of Cardiovascular Diseases 2016年第1期6卷 8-13页

作者： Sherif elwan Tarek Zoheir Tawfik Heba Sayed Assal Shaimaa el-Jaafary Montasser mohamed Hegazy Salwa Tawfik Alshaimaa Mahmoud Aboulfotooh Foad abd-allah Department of Internal Medicine National Research Institute Cairo Egypt Department of Neurology Cairo University Cairo Egypt

Background: The metabolic syndrome (MetS) is a clustering of vascular risk factors that tend to increase the risk of occurrence of diabetes mellitus type 2 (DMT2), cardiovascular and cerebro-vascular ischemic events. The aim of the present study is to investigate the association of extra-cranial and intracranial arterial atherosclerosis as well as silent brain infarction (SBI) with MetS, thereby determining the potential cerebrovascular atherosclerotic risk of MetS in the Egyptian population. Methods: A case control study was conducted on 50 Egyptian subjects with MetS and 30 without with age range from 40 - 60 years old. All participants were free from cerebrovascular ischemic events [stroke or transient ischemic attack (TIA)]. All participants underwent complete neurological examination, assessment of the diagnostic criteria for MetS, carotid and transcranial duplex ultrasonography (U/S) and brain MRI. Results: Preclinical carotid atherosclerosis (athero-sclerotic plaques with ely, there was a highly significant association between MetS and SBI even after adjustment for age and other confounders (P value = 0.001). Conclusion: Metabolic syndrome is an important factor associated with mild to moderate atherosclerosis (<50% stenosis) and silent brain infarcts among asymptomatic individuals. Interventions to reduce MetS are important for prevention of subclinical and clinical cerebral atherosclerotic disease.

关键词： Metabolic Syndrome Preclinical Atherosclerosis Silent Brain Infarction Neurovascular Ultrasound Brain MRI Egyptian Population

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Characterization of Upper Air Way Tract in Snoring and Non-Snoring Patients: A CT Based Study

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Open Journal of Radiology 2016年第3期6卷 181-190页

作者： Fathia abd el Rahman mohamed Alamin Caroline Edward Ayad College of Medical Applied Science Jazan University Jazan KSA College of Medical Radiological Science Sudan University of Science and Technology Khartoum Sudan

Snoring is part of the spectrum of sleep disordered breathing. The patients with snoring should be evaluated for nasal airway obstruction. In this study, the upper air way tract was characterized in snoring patients and compared with none snoring using a quantify method for the corresponding anatomic upper air way (UA) parameters examined by Computerized Tomography (CT). Two hundred Asian patients undergoing CT scanning for head and neck were included and were divided into two groups (snoring group [n = 127] and non-snoring group [n = 73]) (mean age: 44.8 ± 15.9 years and 26.2 ± 7.0). Total 8 parameters were measured on sagital reconstructed CT images for each subject. The differences in neck circumference (NC), linear distance between mandibular plane and hyoid bone (Mp-H), upper airway length (UAL), the maximum thickness of the soft palate (SP max), soft palate length (PNS-U), linear distance between anterior and posterior nasal spine (ANS-PNS), retroglosal width (RS), retroplatal width (RP) between the snoring and non-snoring groups were compared statistically using independent sample t-test. Results showed that the NC, UAL, and SP max were significantly higher in snoring group;however RP was found to be significantly lower. Inferior positioning of hyoid bone gives longer measurement for MP-H. In snoring group UAL was found to be significantly different at p ≤ 0.000 between the two genders. All the measured variables showed no significant differences in respect to age. UA CT quantitative features play an important role in the characterization of the anatomy and are compared between snoring patients and non-snoring subjects.

关键词： Snoring Upper Air Way Tract Computerized Tomography

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Components Assignment Problem for Multi-Source Multi-Sink Flow Networks with Reliability and Budget Constraints

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Journal of Computer and Communications 2022年第6期10卷 99-111页

作者： Noha Nasr elden Moatamad Hassan mohamed abd el-Aziz Mathematics and Computer Science Department Faculty of Science Aswan University Aswan Egypt Information Systems Department Faculty of Computer and Information Sciences Ain Shams University Cairo Egypt

System reliability optimization problem of multi-source multi-sink flow network is defined by searching the optimal components that maximize the reliability and minimize the total assignment cost. Therefore, a genetic-based approach is proposed to solve the components assignment problem under budget constraint. The mathematical model of the optimization problem is presented and solved by the proposed genetic-based approach. The proposed approach is based on determining the optimal set of lower boundary points that maximize the system reliability such that the total assignment cost does not exceed the specified budget. Finally, to evaluate our approach, we applied it to various network examples with different numbers of available components;two-source two-sink network and three-source two-sink network.

关键词： Multi-Source Multi-Sink Stochastic-Flow Networks System Reliability Optimization Components Assignment Problem

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Assessment and Distribution of Heavy Metals Pollutants in Manzala Lake, Egypt

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Journal of Geoscience and Environment Protection 2015年第6期3卷 107-122页

作者： Mahmoud abd el-Kawy Zahran Yasser Ahmed el-Amier abdelhamid Ahmed elnaggar Hoda abd el-Azim mohamed Muhammad abd el-Hady el-Alfy Botany Department Faculty of Science Mansoura University Mansoura Egypt Soils Department Faculty of Agriculture Mansoura University Mansoura Egypt Marine Pollution Department National Institute of Oceanography and Fisheries Suez Egypt

Contamination with heavy metals is one of the most serious problems in the aquatic environments. In Egypt, Manzala Lake is suffering from this problem. The objective of this work was to assess heavy metals pollutants and their spatial distribution in Manzala Lake using GIS technique. Georeferenced water and sediment samples were randomly collected from the lake. The detected heavy metals were: Fe, Pb, Cu, Cd, Cr, Zn and Co. The obtained results indicated that the highest concentrations of heavy metals were observed in the northeastern and the southern parts of the lake nearby drains. This could be attributed to industrial, agricultural and municipal wastes coming through the drains especially Bahr el-Baqar drain and the industrial wastes coming from Port Said drains. From the geo-accumulation index, it was noticed that the lake is more polluted with cadmium and lead in the hydrosoils samples. All metals in water are within the EPA standard limit except for cadmium. Geostatistics provides effective methods to quantify the contaminated waters and sediments which support decision-making about redevelopment scenarios or remediation techniques.

关键词： Manzala Lake Heavy Metals Indices Pollution GIS

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New Approach for the Synthesis of Pyrano[2,3-d]- thiazoles

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材料科学与工程（中英文A版） 2011年第5X期1卷 705-710页

作者： mohamed Sayed abd-elaal elgay Shaban Ibrahim mohamed Hassan Ahmed Eyada Tarek Ahmed abd-el-Aziz Gameel Ahmed mohamed el-hag All Department of Chemistry Faculty of Science Al-Azhar University in Assiut Assiut 71524 Egypt Technology Engineering Institute Tamoh Giza Egypt Department of Chemistry Faculty of Science Al-Azhar University Nasr City Cairo Egypt

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Spectroscopic and Fluorescence Studies on the Trivalent Ce,Eu,Nd and La Metal Ions Rhodamine CFlorescent Dye Complexes

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光谱学与光谱分析 2021年第10期41卷 3311-3315页

作者： Moamen S.Refat Mahmoud Salman Akram M.el-Didamony Hammad Fetooh Eman S.E.abd el-Maksoud mohamed Y.el-Sayed Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry Faculty of ScienceAl-Hussein Bin Talal UniversityP.O.Box 20 Ma’anJordan Department of Chemistry Faculty of ScienceZagazig UniversityEgypt Chemistry Department College of ScienceJouf UniversityP.O.Box:2014 SakakaSaudi Arabia

The four isolates solid complexes:[La(RHC)(NO_(3))_(2)]·3H_(2)O,[Nd(RHC)(NO_(3))_(2)]·4H_(2)O,[Eu(RHC)(NO_(3))_(2)]·2H_(2)O,and[Ce(RHC)(NO_(3))_(2)]·5H_(2)O that obtained by the reaction of the nitrate salts of the Ce(Ⅲ),Eu(Ⅲ),Nd(Ⅲ)and La(Ⅲ)ions and rhodamie C(RHC)ligand were interpretative using elemental analysis(C,H and N),molar conductivity,infrared,electronic,fluorescence and 1H-NMR spectra to achieve the speculated suitable *** low molar conductance values of the synthesized RHC complexes concluded the non-electrolytic *** infrared spectra recorded the absence of stretching vibrationν(OH)of the—COOH and presence of two new vibration bands at 1597~1601 and 1383~1399 cm^(-1)which were assigned toνas(COO-)andνs(COO-).The difference between them revealed that the carboxylate group acts as a bidentate ligand.1HNMR spectra of Europium and lanthanum(Ⅲ)complexes were supported the FTIR results based on the absent of proton of the carboxylic ***,the microanalytical and spectroscopic results deduced that RHC acts as a monobasic bidentate ligand,and coordinated to the central metal(Ⅲ)ions via the two oxygen atoms of deprotonated carboxylic *** studies were performed on the metal complexes of Ce^(3+),Tb^(3+),Th^(4+),Gd^(3+)and La^(3+),that referred a quenching in the fluorescene intensity of rhodamine C in the aqueous state after *** antimicrobial assessment against some kind of bacteria and fungi were also checked and recorded enhancement in case of their complexes.

关键词： Rhodamine C Chelation Spectroscopic Thermogravimetric Lanthanides

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Needleless Contasure versus TVT-O in Women with Stress Urinary Incontinence

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Open Journal of Obstetrics and Gynecology 2020年第8期10卷 1107-1121页

作者： abd el-Moneim abd el-Aziz Saleh Mahmoud Ahmed Ghareb Diab Alsayed mohamed Ibrahiem Walid mohamed elnagar Mohammed Hassan elsayed Barakat Obstetrics & Gynecology Department Faculty of Medicine Zagazig University Zagazig Egypt Urology Department Faculty of Medicine Zagazig University Zagazig Egypt

Objectives: The aim of this thesis is to determine the clinical effectiveness, safety and cost-effectiveness of Single Incision needleless Mini-Slings compared with tension-free Standard Mid-urethral Sling in the surgical management of female stress urinary incontinence, but with less side effects. Methods: The study will be conducted in Zagazig University Hospitals. From 2018 to Sept. 2019, 40 cases were enrolled in the study and were randomized by envelope technique at the time of surgery to either a trans-obturator vaginal tape (TOT) or Needleless anti-incontinence procedure. The patients will be divided into 2 groups: Group 1 patient treated by standard sling (TOT). Group 2 those treated by mini-sling. Parameters in perioperative period such as operating time, intraoperative hemorrhage volume, length of stay in hospital, intraoperative complications, and postoperative pain of each patient were recorded. The sample size was calculated to be 40 cases (20 cases will be treated by standard slings, 20 case will be treated by mini-sling). Results: A total of 40 patients assessed for eligibility were randomized into Needleless groups. There were no significant differences in age, body mass index, process, parity, pad test or the assessment of preoperative quality of life between the two groups. In the perioperative period, statistically significant differences between the two groups were found in operating time, intraoperative hemorrhage volume, groin pain scores at 24 h after operation and length of stay in hospital (P eless and TOT

关键词： Mini-Sling Needleless Stress Urinary Incontinence TVT-O TVT Contasure

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A Modified Interactive Stability Algorithm for Solving Multi-Objective NLP Problems with Fuzzy Parameters in Its Objective Functions

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American Journal of Operations Research 2016年第1期6卷 8-16页

作者： mohamed abd el-Hady Kassem Ahmad M. K. Tarabia Noha mohamed el-Badry Mathematics Department Faculty of Science Tanta University Tanta Egypt Mathematics Department Faculty of Science Damietta University Damietta Egypt

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.

关键词： Multi-Objective Nonlinear Programming Stability Trade-Off Method Fuzzy Parameters

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