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Energy Engineering 2024年第8期121卷 2023-2038页

作者： Abdul Sattar Laghari Mohammad Waqas Chandio Laveet Kumar mamdouh el Haj Assad Department of Mechanical Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of Mechanical and Industrial Engineering College of EngineeringQatar UniversityDoha00000Qatar Sustainable&Renewable Energy Engineering Department University of SharjahSharjah00000United Arab Emirates

The selection of working fluid significantly impacts the geothermal ORC’s *** a mixture as a working fluid is a strategy to improve the output of geothermal *** the current study,modelling and thermodynamic analysis of ORC,using geothermal as a heat source,is carried out at fixed operating *** model is simulated in the Engineering Equation Solver(EES).An environment-friendly mixture of fluids,i.e.,R245fa/R600a,with a suitable mole fraction,is used as the operating *** mixture provided the most convenient results compared to the pure working fluid under fixed operating *** impact of varying the evaporator pressure on the performance parameters,including energy efficiency,exergy efficiency and net power output is *** system provided the optimal performance once the evaporator pressure reached the maximum *** efficiencies:Energy and Exergy,and Net Power output of the system are 16.62%,64.08%and 2199 kW for the basic cycle and 20.72%,67.76%and 2326 kW respectively for the regenerative cycle.

关键词： Organic rankine cycle internal heat exchanger moderate-temperature geothermal source mixture of the fluid exergy

Measuring Impact of Lean Manufacturing Tools for Continuous Improvement on Economic Sustainability

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 452-474页

作者： Luis Javier Márquez Figueroa Jorge Luis García-Alcaraz Ahmed I.Osman Alfonso Jesús Gil López Yashar Aryanfar Mika Sillanpää mamdouh el Haj Assad Department of electrical Engineering and Computer Science Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico Department of Industrial Engineering and Manufacturing Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico School of Chemistry and Chemical Engineering Queens UniversityBelfastNorthern IrelandUK Department of Economic and Managerial Sciences University of La RiojaLa RiojaSpain Department of Chemical Engineering University of JohannesburgJohannesburgSouth Africa Department of Sustainable and Renewable Energy Engineering University of SharjahSharjahUAE

Using Lean Manufacturing(LM)tools in production processes is crucial for companies’economic,environmental,and social sustainability *** study shows a structural equation model(SEM)that shows the relationship between LM Tools like Kaizen(KAI),Gemba(GEM),Value Stream Mapping(VSM)and Key Performance Indicator(KPI)with Economic Sustainability(ECS).Seven hypotheses were evaluated with data from 179 responses to a questionnaire about the Mexican maquiladora industry,showing that these variables are *** a 95%confidence level,the model was evaluated using the partial least squares *** findings indicate that the relationships between KAI and GEM and KAI and VSM have the strongest relationship,followed by VSM and ECS;however,VSM has the strongest effect on *** on these findings,it is recommended that managers adopt a continuous improvement(KAI)approach based on working directly on the shop floor(GEM and VSM)to support their decisions regarding economic growth(ECS).

关键词： Lean manufacturing economic sustainability structural equation model quality improvement

Optimal Seat Suspension Design Using Genetic Algorithms

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Journal of Mechanics Engineering and Automation 2011年第1期1卷 44-52页

作者： Wael Abbas Ossama B. Abouelatta magdy el-azab.mamdouh el-saidy Adel A. Megahed Engineering Physics and Mathematics Department Faculty of Engineering （Mataria） Helwan University Cairol 1718 Egypt Production Engineering and Mechanical Design Department Faculty of Engineering Mansoura University Mansoura 35516 Egypt Mathematics and Engineering Physics Department Faculty of Engineering Mansoura University Mansoura 35516 Egypt Mathematics and Engineering Physics Department Faculty of Engineering Cairo University Cairo 12211 Egypt

The linear seat suspension is considered due to the low cost consideration therefore, the optimal linear seat suspension design method can be used for this purpose. In this paper, the design of a passive vehicle seat suspension system was handled in the framework of linear optimization. The variance of the dynamic load resulting from the vibrating vehicle operating at a constant speed was used as the performance measure of a suspension system. Using 4-DOF human body model developed by Abbas et al., with linear seat suspension and coupled with half car model. A genetic algorithm is applied to solve the linear optimization problem. The optimal design parameters of the seat suspension systems obtained are kse = 3 012.5 N/m and cse = 1 210.4 N.s/m, respectively.

关键词： Biodynamic response seated human models simulation genetic algorithms.

Parameters Affecting Energy Consumption for Producing High Carbon Ferromanganese in a Closed Submerged Arc Furnace

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Journal of Iron and Steel Research International 2014年第7期21卷 666-672页

作者： Azza Ahmed Hossam Halfa Mohamed K.el-Fawakhry Hoda el-Faramawy mamdouh Eissa Steel Technology Metallurgical Research and Development Institute

The power consumption is considered to be the most important factor affecting the production cost of fer romanganese alloy. Different parameters affecting the energy consumption for industrial production of high carbon ferromanganese HCFeMn were investigated in a closed submerged arc furnace. The analysis of industrial data revealed that the most energy consumed factors were the direct reduction by solid carbon, Boudouard reaction, metal and slag formation, and decomposition of fluxing materials （limestone and dolomite）. To reduce the energy con- sumption and minimize the energy losses in the production process of HCFeMn, it was recommended to use Mn blend with minimum Mn to Fe ratio of 6 and lower SiO2 content or higher basicity. The added coke must be adjusted according to the material balance to prevent the over-coke and to minimize the highly endothermic ＂Boudouard reac tion＂. In addition, it was recommended to work at basic slags with the ratio of （CaO＋MgO） to Si（）2 equal to 1.0- 1.2 instead of much higher slag basicity. Furthermore, the mass losses had to be minimized through adjusting the handling and charging process and to take care of all metal produced.

关键词： high carbon ferromanganese production energy consumption carbonate decomposition Boudouard reaction slag basicity energy loss

Effect of cooling rate and composition on microstructure and mechanical properties of ultrahigh-strength steels

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Journal of Iron and Steel Research International 2019年第12期26卷 1350-1365页

作者： Mohammed Ali David Porter Jukka Komi mamdouh Eissa Hoda el Faramawy Taha Mattar Materials and Mechanical Engineering Centre for Advanced Steels ResearchUniversity of OuluOulu 90014Finland Steel Technology Department Central Metallurgical Research and Development InstituteHelwanCairo 11421Egypt

The influence of cooling rate on the microstructure and mechanical properties of two new ultrahigh-strength steels(UHSSs)with different levels of C,Cr and Ni has been evaluated for the as-cooled and untempered *** UHSS had higher contents of C and Cr,while the other one had a higher Ni *** the basis of dilatation curves,microstructures,macrohardness and microhardness,continuous cooling transformation diagrams were constructed as a guide to heat treatment *** rates(CRs)of 60,1 and 0.01°C/s were selected for more detailed *** characterization was made by laser scanning confocal microscopy,field emission scanning electron microscopy combined with electron backscatter diffraction,electron probe microanalysis and X-ray *** properties were characterized using macrohardness,tensile and Charpy V-notch impact *** with the higher C and Cr contents showed lower transformation temperatures and slower bainite formation kinetics than that with the higher Ni *** cooling rates led to lower volume fractions and carbon contents of retained austenite together with finer prior austenite grain size,as well as effective final grain size and lath *** changes were accompanied by higher yield and tensile *** best combinations of strength and toughness were obtained with martensitic microstructures and by avoiding the formation of granular bainite accompanied by proeutectoid carbides at low *** the cooling rates studied,UHSS with the higher C and Cr contents showed the higher hardness and strength but at the cost of toughness.

关键词： Ultrahigh-strength steel electroslag remelting Continuous cooling transformation diagram Microstructure feature Mechanical property

Synthesis and Antimicrobial Activity of Some Condensed [4-（2,4,6-Trimethylphenyl）-1 （2H）-oxo-phthalazin-2-yl]acetic Acid Hydrazide

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Chinese Journal of Chemistry 2012年第3期30卷 616-626页

作者： EI-Hashash, MaherA EI-Kady, AhmedY Taha, mamdouh A el-Shamy, Ibrahim E Chemistry Department Faculty of Science Ain Shams University Cairo Egypt Chemistry Department Faculty of Science Fayoum University Fayoum Egypt

Some new 1,2,4-triazolo-, 1,3,4-oxadiazolo-, 1,3,4-thiadiazol-, and pyrazolo-2,4,6-trimethylphenyl-1（2H）-oxo- phthalazine derivatives were synthesized and identified by IR, ^1H NMR, ^13C NMR, MS and elemental analys... 详细信息

关键词： 1(2H)-oxo-phthalazine 1,2,4-triazole 1,3,4-oxadiazole 1,3,4-thiadiazole antimicrobial activity

Utilization of Machine Learning Methods in Modeling Specific Heat Capacity of Nanofluids

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Computers, Materials & Continua 2022年第1期70卷 361-374页

作者： mamdouh el Haj Assad Ibrahim Mahariq Raymond Ghandour Mohammad Alhuyi Nazari Thabet Abdeljawad Sustainable and Renewable Energy Engineering Department University of SharjahP.O.Box 27272SharjahUAE College of Engineering and Technology American University of theMiddle EastKuwait Faculty of New Sciences and Technologies University of TehranTehranIran Department of Mathematics and General Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia Department of Medical Research China Medical UniversityTaichung40402Taiwan Department of Computer Science and Information Engineering Asia UniversityTaichungTaiwan

Nanofluids are extensively applied in various heat transfer mediums for improving their heat transfer characteristics and hence their *** heat capacity of nanofluids,as one of the thermophysical properties,performs principal role in heat transfer of thermal mediums utilizing *** this regard,different studies have been carried out to investigate the influential factors on nanofluids specific ***,several regression models based on correlations or artificial intelligence have been developed for forecasting this property of *** the current review paper,influential parameters on the specific heat capacity of nanofluids are ***,the proposed models for their forecasting and modeling are *** to the reviewed works,concentration and properties of solid structures in addition to temperature affect specific heat capacity to large extent and must be considered as inputs for the ***,by using other effective factors,the accuracy and comprehensive of the models can be ***,some suggestions are offered for the upcoming works in the relevant topics.

关键词： Specific heat capacity nanofluid artificial neural network concentration

miR-29a Promotes Lipid Droplet and Triglyceride Formation in HCV Infection by Inducing Expression of SREBP-1c and CAV1

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Journal of Clinical and Translational Hepatology 2016年第4期4卷 293-299页

作者： Mennatallah mamdouh Mahdy Nada magdy el-Ekiaby Rana Mahmoud Hashish Radwa Ayman Salah Rasha Sayed Hanafi Hassan Mohamed el-Said Azzazy Ahmed Ihab Abdelaziz Department of Pharmaceutical Chemistry German University in Cairo New Cairo City Egypt Department of Pharmacology and Toxicology German University in Cairo New Cairo City Egypt School of Medicine New Giza University Cairo Egypt Department of Pharmaceutical Biology German University in Cairo New Cairo City Egypt Department of Stem Cells and Regenerative Medicine Zewail City of Science and TechnologyGiza Egypt Department of Chemistry Novel Diagnostic & Therapeutics American University in Cairo New Cairo City Egypt

Aims:To examine the regulation of SREBP-1c and CAV1 by microRNA-29a (miR-29a) in cells infected with hepatitis C virus (HCV) in an attempt to control HCV-induced nonalcoholic fatty liver ***:In order to examine the manipulation of SREBP-1c and CAV1 by miR-29a,oleic acid (OA)-treated JFH-I-infected Huh-7 cells were *** was added 24 h post-transfection and gene expression was investigated by qRT-PCR at 48 h post *** functional impact of the observed alteration in SREBP-1c and CAV1 expression was analyzed by examining lipid droplet (LD) and triglyceride (TG) content at 72 h post-OA treatment using light microscopy and spectrophotometry,*** load was quantified by qRT-PCR at 72 h ***:OA treatment induced the expression of miR-29a and SREBP-1c,as compared to untreated *** miR-29a expression led to a significant up-regulation of SREBP-1c as well as CAV1 compared to mock untransfected *** expression of miR-29a resulted in a marked increase in LDs and their respective TGs,while miR-29a antagomirs decreased both the LD and TG content compared to mock untransfected ***,forcing the expression of miR-29a in JFH-1 HCV-infected Huh-7 cells resulted in 53% reduction in viral titers compared to mock untransfected Huh-7 ***:Inducing miR-29a expression significantly induces SREBP-1c and CAV1 expression,thereby increasing LDs as well as their respective ***,forcing the expression of miR-29a resulted in reduction of HCV RNA levels in Huh-7 cells.

关键词： Caveolin-1 HCV Lipid droplets MicroRNA-29a SREBP-1c

Calcium channel α2δ1 subunit as a novel biomarker for diagnosis of hepatocellular carcinoma

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Cancer Biology & Medicine 2018年第1期15卷 52-60页

作者： Sana Amhimmid Badr Maryan Waheeb Fahmi Manal Mahmoud Nomir mamdouh Mohammad el-Shishtawy Biochemistry Department Faculty of Pharmacy Medical Oncology Unit Internal Medicine DepartmentFaculty of Medicine Clinical Pathology Department Students Hospital Mansoura University

Objective:Hepatocellular carcinoma(HCC)is the fifth most common malignancy *** identification of new simple,inexpensive and highly accurate markers for HCC diagnosis and screening is *** case-control study evaluates the role of annexin A2 and voltage-gated calcium channelsα2δ1 subunit as serum biomarkers for HCC ***:The study comprised three groups:group 1,50 patients with an initial diagnosis of HCC associated with chronic hepatitis C virus infection;group 2,25 patients diagnosed with chronic hepatitis C virus infection and cirrhosis without any evidence of HCC;and group 3,15 healthy *** participants were subjected to clinical and laboratory investigations,and radiological *** serum levels of alpha-fetoprotein(AFP),annexin A2,and theα2δ1 subunit were evaluated by using elISA ***:The serum levels of annexin A2 significantly increased in patients with HCC(10.4±2.5 ng/m L;Pels in patients with HCC comparing to those with ***α2δ1 subunit significantly increased in patients with HCC(20.12±3.7 ng/m L)comparing to that in patients with cirrhosis(10.41±3.4 ng/m L,P<0.001)and healthy controls(10.2±2.9 ng/m L,P<0.001).Conclusions:The serumα2δ1 subunit may function as a new biomarker for HCC ***,serum annexin A2 has low diagnostic value as an HCC marker,especially in patients with underlying cirrhosis.

关键词： Hepatocellular carcinoma tumor initiation cell marker α2δ1 subunit annexin A2 alpha-fetoprotein

Modeling CO_(2) Emission of Middle Eastern Countries Using Intelligent Methods

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Computers, Materials & Continua 2021年第12期69卷 3767-3781页

作者： mamdouh el Haj Assad Ibrahim Mahariq Zaher Al Barakeh Mahmoud Khasawneh Mohammad Ali Amooie Sustainable and Renewable Energy Engineering Department University of SharjahPO Box 27272SharjahUAE College of Engineering and Technology American University of the Middle EastKuwait Department of Mechanical and Industrial Engineering Louisiana State UniversityUSA

CO_(2) emission is considerably dependent on energy consumption and on share of energy sources as well as on the extent of economic ***,these factors must be considered for CO_(2) emission prediction for seven middle eastern countries including Iran,Kuwait,United Arab Emirates,Turkey,Saudi Arabia,Iraq and *** order to propose a predictive model,a Multilayer Perceptron Artificial Neural Network(MLP ANN)is *** transfer functions including logsig,tansig and radial basis functions are utilized in the hidden layer of the ***,various numbers of neurons are applied in the structure of the *** is revealed that using MLP ANN makes it possible to accurately predict CO_(2) emission of these *** addition,it is concluded that using logsig transfer function leads to the highest accuracy with minimum value of mean squared error(MSE)which is followed by the networks with radial basis and tansig transfer *** R-squared of the networks with logsig,radial basis and tansig transfer functions are 0.9998,0.9997 and 0.9996,***,comparison of the proposed model with a similar study,considered five countries in the same region,reveals higher accuracy in term of MSE.

关键词： CO_(2)emission artificial neural network middle eastern countries transfer function