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Advances in Manufacturing 2021年第2期9卷 286-303页

作者： Joseck Nyaboro Mahmoud ahmed Hassan El-Hofy mohamed El-Hofy Department of Industrial and Manufacturing Engineering Egypt-Japan University of Science and Technology(E-JUST)Alexandria 21934Egypt Department of Energy Resources Engineering Egypt-Japan University of Science and Technology(E-JUST)Alexandria 21934Egypt Advanced Manufacturing Research Centre(AMRC)with Boeing The University of SheffieldRotherham S605TZUK

The machining of hard-to-cut materials with a high degree of precision and high surface quality is one of the most critical considerations when fabricating various state-of-the-art engineered *** this investigation,a comprehensive three-dimensional model was developed and numerically simulated to predict kerf profiles and material removal rates while drilling the aluminum-7075-T6 aerospace *** profile and material removal prediction involved three stages:jet dynamic flow modeling,abrasive particle tracking,and erosion rate *** investigations were conducted to validate the developed *** results indicate that the jet dynamic characteristics and flow of abrasive particles alter the kerf profiles,where the top kerf diameter increases with increasing jet pressure and standoff *** kerf depth and hole aspect ratio increase with jet pressure,but decrease with standoff distance and machining *** profiles were characterized by progressive edge rounding and parabolic *** can be minimized by utilizing high jet pressure and small standoff *** material removal rate increases with increasing jet pressure,abrasive particle size,and exposure time,but decreases with increasing standoff distance.

关键词： Non-traditional machining Abrasive waterjet machining Computational fluid dynamics(CFD) Erosion modeling Kerf characteristics

Improved Hybrid Swarm Intelligence for Optimizing the Energy in WSN

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Computer Systems Science & Engineering 2023年第8期46卷 2527-2542页

作者： ahmed Najat ahmed JinHyung Kim Yunyoung Nam mohamed Abouhawwash Department of Computer Engineering Lebanese French UniversityErbil44001Iraq B LIFE Inc. Suwon16463Korea Department of ICT Convergence Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA

In this current century,most industries are moving towards automation,where human intervention is dramatically *** revolution leads to industrial revolution 4.0,which uses the Internet of Things(IoT)and wireless sensor networks(WSN).With its associated applications,this IoT device is used to compute the receivedWSN data from devices and transfer it to remote locations for *** general,WSNs,the gateways are a long distance from the base station(BS)and are communicated through the gateways nearer to the *** the gateway,which is closer to the BS,energy drains faster because of the heavy load,which leads to energy issues around the *** the sensors are battery-operated,either replacement or recharging of those sensor node batteries is not possible after it is deployed to their corresponding *** that situation,energy plays a vital role in sensor *** reducing the network energy consumption and increasing the network lifetime,this paper proposed an efficient cluster head selection using Improved Social spider Optimization with a Rough Set(ISSRS)and routing path selection to reduce the network load using the Improved Grey wolf optimization(IGWO)approach.(i)Using ISSRS,the initial clusters are formed with the local nodes,and the cluster head is chosen.(ii)Load balancing through routing path selection using *** simulation results prove that the proposed optimization-based approaches efficiently reduce the energy through load balancing compared to existing systems in terms of energy efficiency,packet delivery ratio,network throughput,and packet loss percentage.

关键词： Wireless sensor networks(WSN) internet of things(IoT) energy efficiency load balance sensors grey wolf optimization social spider optimization

Synthesis of thiopyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]furo[3,2-d]pyrimidines

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Chinese Chemical Letters 2010年第6期21卷 669-673页

作者： Essam Kh. ahmed mohamed A. Ameen Chemistry Department Faculty of ScienceEl Minia UniversityEl Minia 61519Egypt

Reactions of the 6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrile derivative 1 withα-halo-carbonyl compounds gave the ortho-substituted intermediates 2a-c which were converted into furo[2,3-b]thiopyrano[4,3-d]pyridines 3a-c by fusion of a furan moiety under basic *** cyclization of 3a-c led to a fusion of a pyrimidine ring,yielding the tetracyclic products 6,7 and *** addition,condensation of 6 with various aromatic aldehydes afforded the corresponding imines 9a,*** reaction of 7 gave products 10a,b.

关键词： S N-Heterocycles S N O-Heterocyles Furo[2 3-b]thiopyrano[4 3-d]pyridine Thiopyranopyridofuropyrimidines

Techniques for colorectal anastomosis

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World Journal of Gastroenterology 2010年第13期16卷 1610-1621页

作者： Yik-Hong Ho mohamed ahmed Tawfi k Ashour Discipline of Surgery School of Medicine James Cook University

Colorectal anastomotic leak remains one of the most feared post-operative complications, particularly after anterior resection of the rectum with, the shift from abdomino-peritoneal resections to total mesorectal excision and primary anastomosis. The literature fails to demonstrate superiority of stapled over hand-sewn techniques in colorectal anastomosis, regardless of the level of anastomosis, although a high stricture rate was noted in the former technique. Thus, improvements in safety aspects of anastomosis and alternatives to handsewn and stapled techniques are being sought. Here, we review alternative anastomotic techniques used to fashion bowel anastomosis. Compression anastomosis using compression anastomotic clips, endoluminal compression anastomotic rings, AKA-2, biofragmental anastomotic rings, or Magnamosis all involve the concept of creating a sutureless end-to-end anastomosis by compressing two bowel ends together, leading to a simultaneous necrosis and healing process that joins the two lumens. Staple line reinforcement is a new approach that reduce the drawbacks of staplers used in colorectal practice, i.e. leakage, bleeding, misfi ring, and inadequate tissue approximation. Various nonabsorbable, semi or fully absorbable materials are now available. Two other techniques can provide alternative anastomotic support to the suture line: a colorectal drain and a polyester stent, which can be utilized in ultra-low rectal excision and can negate the formation of a defunctioning stoma. Doxycycline coated sutures have been used to overcome the post-operative weakness in anastomosis secondary to rapid matrix degradation mediated by matrix metalloproteinase. Another novel technique, the electric welding system, showed promising results in construction of a safe, neat, smooth sutureless bowel anastomosis. Various anastomotic techniques have been shown to be comparable to the standard techniques of suturing and stapling. However, most of these alternatives need t

关键词： Alternative anastomosis Compression anastomotic clip Compression anastomotic ring Biofragmental anastomotic ring AKA-2 Magnamosis (magnetic anastomosis) Matrix metallo-proteinase Sutureless

Derivation of travel demand forecasting models for low population areas:the case of Port Said Governorate,North East Egypt

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第3期1卷 196-208页

作者： ahmed mohamed Semeida Department of Civil Engineering Faculty of EngineeringPort Said UniversityPort SaidEgypt

In the last decades, there has been substantial development in modeling techniques of travel demand estimation. For low population areas the external trip estimation is important but usually neglected in travel demand modeling process. In Egypt, the researches in this field are scarce due to lack of data. Accordingly, this paper aims to identify and estimate the main variables that affect the travel demand in low population areas, and to develop models to predict them. The study focused on the Port Said Govemorate in North East Egypt. A special questionnaire had been prepared in 2010 depending on interviews of passengers at basic taxi terminals in Port Said. And 2211 filled questionnaires were offering for research. To analyze the data, two modeling procedures were used. One is the multiple linear regression and the other is the generalized linear modeling （GLM） applying normal distributions. It is found that GLM procedure offers more suitable and accurate approach than the linear regression for developing number of trips. The final demand models have statistics within the acceptable regions and, also, they are conceptually reasonable. These results are so important for Egyptian highway authorities to improve the efficiency of highway transportation system in Egypt.

关键词： travel demand linear regression generalized linear modeling low population areas Port Said

Load Frequency Control of Multi-interconnected Renewable Energy Plants Using Multi-Verse Optimizer

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Computer Systems Science & Engineering 2021年第5期37卷 219-231页

作者： Hegazy Rezk mohamed A.mohamed ahmed A.Zaki Diab N.Kanagaraj College of Engineering at Wadi Addawaser Prince Sattam Bin Abdulaziz UniversityWadi Addawaser11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringMinia UniversityMinia61111Egypt

A reliable approach based on a multi-verse optimization algorithm(MVO)for designing load frequency control incorporated in multi-interconnected power system comprising wind power and photovoltaic(PV)plants is presented in this *** has been applied for optimizing the control parameters of the load frequency controller(LFC)of the multi-source power system(MSPS).The MSPS includes thermal,gas,and hydro power plants for energy ***,the MSPS is integrated with renewable energy sources(RES).The MVO algorithm is applied to acquire the ideal parameters of the controller for controlling a single area and a multi-area MSPS integrated with *** link is utilized in shunt with AC multi-areas interconnection tie *** proposed scheme has achieved robust performance against the disturbance in loading conditions,variation of system parameters,and size of step load perturbation(SLP).Meanwhile,the simulation outcomes showed a good dynamic performance of the proposed controller.

关键词： Load frequency control multi-verse optimization multi-area power system renewable energy sources

Enhancing the explosive characteristics of a Semtex explosive by involving admixtures of BCHMX and HMX

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Defence Technology（防务技术） 2020年第2期16卷 487-492页

作者： ahmed Elbeih ahmed K.Hussein Tamer Elshenawy Svatopluk Zeman Sara M.Hammad Ahmad Baraka mohamed A.Elsayed mohamed Gobara Hesham Tantawy Military Technical College Kobry ElkobbahCairoEgypt Technical Research Center CairoEgypt Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCzech Republic Faculty of Pharmacy University of CairoGizaEgypt

A well-known ternary plastic explosive,Czech Semtex 1H,contains a mixture of PETN and RDX softened by *** this work,BCHMX was used to replace PETN in Semtex 1H to form Sem-BC+*** addition,another mixture based on BCHMX and HMX as energetic fillers bonded by the polymeric matrix of Semtex 1H(Sem-BC+HMX)was *** particle size distribution of each individual explosive was determined to obtain the optimum mixing *** and impact sensitivities were *** velocity of detonation was reported practically and the detonation properties were calculated by EXPLO5 *** explosive strength of each sample was measured by the ballistic mortar *** conclusion confirms that the velocity of detonation of Sem-BC+HMX was the highest in comparison with the prepared ***-BC+RDX has the least impact and frictions ***-BC+RDX has higher detonation velocity,detonation properties and explosive strength than Semtex *** of BCHMX in Semtex 1H as a replacement for PETN is the candidate to produce a high performance advanced Czech plastic explosive.

关键词： Semtex Explosives Combustion Sensitivity Detonation Explosive strength

Peripartum depression and its predictors:A longitudinal observational hospital-based study

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World Journal of Psychiatry 2022年第8期12卷 1061-1075页

作者： Sherifa ahmed Hamed mohamed Elwasify mohamed Abdelhafez mohamed Fawzy Department of Neurology and Psychiatry Assiut University HospitalAssiut 71516Egypt Department of Psychiatry Mansoura UniversityMansoura 11001Egypt Department of Obstetrics and Gynecology Mansoura UniversityMansoura 11001Egypt

BACKGROUND Depression is a common problem in women in childbearing years due to burdens of motherhood and building a *** studies estimate the prevalence of antepartum depression compared to those in the postpartum *** To estimate the prevalence and the severities of peripartum depression and major depressive disorder and their *** This is a longitudinal observation *** included 200 women scoring≥13 with the Edinburgh Postpartum Depression Scale,indicating presence of symptoms of *** had a gestational age of≥6 wk and did follow-ups until the 10^(th) week to 12^(th) weeks *** of women's reactions to life circumstances and stressors during the current pregnancy were gathered from answers to questions of the designed unstructured clinical *** of depression,anxiety,and parenting stress were determined by the Beck Depression Inventory,State-Trait Anxiety Inventory for Adults,and Parenting Stress Index-Short Form,*** interviewing was done to confirm the diagnosis of major *** the levels of triiodothronine(T3),thyroxine(T4),and thyroid stimulating hormone(TSH)was done in both antepartum and postpartum *** Out of 968(mean age=27.35±6.42 years),20.66%(n=200)of the patients had clinically significant symptoms of depression and 7.44%had major *** premenstrual dysphoria,post-abortive depression,and depression unrelated to pregnancy and were reported in 43%,8%,and 4.5%of the patients,*** stressors were reported in 15.5%of the *** anxiety and parenting stress were reported in 90.5%and 65%of the patients,*** T3,T4,and TSH levels did not significantly differ from reference *** analysis showed that anxiety trait was a predictor for antepartum(standardized regression coefficients=0.514,t=8.507,P=0.001)and postpartum(standardized regression coefficients=0.573,t=0.04

关键词： Peripartum depression Antepartum depression Postpartum depression Anxiety Edinburgh postpartum depression scale Parenting stress

Unsteady Operation of New Type Turbofan Engine with Aerodynamic Torque Converter Reducing Front Fan Speed

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Journal of Thermal Science 2005年第3期14卷 206-210页

作者： Toshiaki KANEMOTO Seita SEKI Kazunori IDENO ahmed mohamed GALAL Kyushu Institute of Technology Sensui 1-1 Tobata Kitakyushu 804-8550 Japan ProfessorKyushu Institute of Technology Sensui 1-1 Tobata Kitakyushu 804-8550 JapanKyushu Institute of Technology Sensui 1-1 Tobata Kitakyushu 804-8550 JapanKyushu Institute of Technology Sensui 1-1 Tobata Kitakyushu 804-8550 Japan

It is desired to increase the rotational speed of the core engine of the turbofan so as to get the best efficiency for the next leap of engine technology. The conventional mechanism in which the front fan is directly connected to the output shaft of a core engine, have a limit of increasing the spool speed, because the fan diameter is very large. The authors have proposed a new driving system in which the front fan is driven through the aerodynamic torque converter. The front fan can work at the best performance at slower speed while the core engine runs more efficiently at higher speed. Continuously, this paper discusses the response of the front fan in the unsteady operation of the core engine, accompanying with the internal flow. The system has the acceptable responsibility in the unsteady operation which is very important for the aircrafts.

关键词： turbofan engine front fan torque converter rotational speed

Adversarial Neural Network Classifiers for COVID-19 Diagnosis in Ultrasound Images

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Computers, Materials & Continua 2022年第1期70卷 1683-1697页

作者： mohamed Esmail Karar Marwa ahmed Shouman Claire Chalopin Department of Industrial Electronics and Control Engineering Faculty of Electronic Engineering(FEE)Menoufia UniversityMenouf32952Egypt Department of Computer Engineering and Networks College of Computing and Information TechnologyShaqra UniversityShaqra11961Saudi Arabia Department of Computer Science and Engineering Faculty of Electronic Engineering(FEE)Menoufia UniversityMenouf32952Egypt Innovation Center for Computer Assisted Surgery(ICCAS) Universit鋞LeipzigLeipzig04103Germany

The novel Coronavirus disease 2019(COVID-19)pandemic has begun in China and is still affecting thousands of patient livesworldwide *** X-ray and Computed Tomography are the gold standardmedical imaging modalities for diagnosing potentially infected COVID-19 cases,applying Ultrasound(US)imaging technique to accomplish this crucial diagnosing task has attracted many physicians *** this article,we propose two modified deep learning classifiers to identify COVID-19 and pneumonia diseases in US images,based on generative adversarial neural networks(GANs).The proposed image classifiers are a semi-supervised GAN and a modifiedGANwith auxiliary *** one includes a modified discriminator to identify the class of the US image using semi-supervised learning technique,keeping its main function of defining the“realness”of tested *** tests have been successfully conducted on public dataset of US images acquired with a convex US *** study demonstrated the feasibility of using chest US images with two GAN classifiers as a new radiological tool for clinical check of COVID-19 *** results of our proposed GAN models showed that high accuracy values above 91.0%were obtained under different sizes of limited training data,outperforming other deep learning-based methods,such as transfer learning models in the recent ***,the clinical implementation of our computer-aided diagnosis of US-COVID-19 is the future work of this study.

关键词： COVID-19 medical imaging machine learning applications adversarial neural networks ultrasound