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Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid ahmed Tadjer Abdelhakim Idir Kong Fah Tee mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Induction of sub-G0 arrest and apoptosis by seed extract of Moringa peregrina（Forssk.） Fiori in cervical and prostate cancer cell lines

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Journal of Integrative Medicine 2019年第6期17卷 410-422页

作者： Maged mohamed Maher abou-Hashem Dina mohamed abo-elmatty Noha Mostafa Mesbah ahmed mohamed Abd EL-Mawgoud Faculty of Pharmacy Pharmacognosy DepartmentZagazig UniversityZagazig 44511Egypt Faculty of Pharmacy Biochemistry DepartmentSuez Canal UniversityIsmailia 41522Egypt Egyptian International Pharmaceuticals Industries Company Tenth of Ramadan City 44629Egypt

Objective: This study investigated cytotoxicity and induction of apoptosis in human cervical cancer cells(HELA) and prostate cancer cells(PC-3) using the most active fraction of Moringa peregrina seed ***: Dried and powdered seeds were extracted using 95% ethanol. The total ethanolic extract was further dissolved in distilled water and separated into petroleum ether, chloroform, ethyl acetate and aqueous extracts. Based on the results of in vitro anticancer studies of all extracts, the most highly active extract was selected for evaluation of apoptosis induction and cell cycle analysis on HELA and PC-3 cells at its half maximal inhibitory concentration using flow cytometry;DNA fragmentation by agarose gel electrophoresis and the expression of protein were measured by Western ***: The chloroform fraction from the ethanolic extract of M. peregrina(CFEE) was the most active antitumor fraction. The selectivity index, determined using the normal Vero cell line, indicated that CFEE had a high degree of selectivity against HELA and PC-3 cells. CFEE induced apoptosis, confirmed by cell cycle arrest at sub-G0 phase and DNA fragmentation. CFEE induced an increase in mRNA expression of caspase-3, a decrease in Bcl-2 mRNA expression, and decreased ATP levels. CFEE increased protein expression of caspase-3 and decreased protein expression of poly-ADP-ribose polymerase-1(PARP-1).Flow cytometric analysis showed an appreciable increase in the number of cells in the early apoptotic stage in CFEE-treated HELA and PC-3 cells. CFEE treatment significantly increased lipid peroxidation(malondialdehyde level) in HELA and PC-3 ***: Seed extract of M. peregrina displayed a significant antitumor effect through apoptosis induction in HELA and PC-3 cells.

关键词： Moringa peregrina Fractionation Antiproliferation Apoptosis

4-Port Octagonal Shaped MIMO Antenna with Low Mutual Coupling for UWB Applications

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1999-2015页

作者： Mahmoud A.Abdelghany mohamed Fathy abo Sree Arpan Desai ahmed A.Ibrahim Electrical Engineering Department College of EngineeringPrince Sattam bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electronic and Communication Department Arab Academy for ScienceTechnology and Maritime TransportCairo11865Egypt Department of Electronics and Communication Engineering CSPITCharotar University of Science and Technology(CHARUSAT)Changa388421India Electronics and Communications Engineering Department Minia UniversityEl-Minia61519Egypt

A4-port multiple-input multiple-output(MIMO)antenna exhibiting lowmutual coupling andUWBperformance is *** octagonal-shaped four-antenna elements are connected with a 50microstrip feed line that is arranged rotationally to achieve the orthogonal polarization for improving the MIMO system *** antenna has a wideband impedance bandwidth of 7.5GHz with S11<−10 dB from(103.44%)3.5–11GHz and inter-element isolation higher than 20 *** validation is carried out by verifying the simulated and measured results after fabricating the *** results in the form of omnidirectional radiation patterns,peak gain(≥4 dBi),and Envelope Correlation Coefficient(ECC)(≤0.01)are extracted to validate the suggested antenna ***,time-domain analysis was investigated to demonstrate the operation of the suggested antenna in wideband ***,the simulated and experimental outcomes have almost similar tendenciesmaking the antenna suitable for its use in UWBMIMOapplications.

关键词： MIMO antenna low mutual coupling time domain analysis UWB antenna

Techno-economic analysis to develop the first wind farm in the Egyptian western desert at Elkharga Oasis

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Clean Energy 2022年第1期6卷 211-225页

作者： mohamed A.Abdelrahman Radwan H.Abdel-Hamid Maged ahmed abo Adma mohamed Daowd Electrical Power and Machines Department Faculty of EngineeringHelwan UniversityCairoEgypt

During the past few years,Egypt has increased the share of electricity generation from renewable energy sources to achieve the renewable-energy *** Egyptian Ministry of Electricity and Renewable Energy has set an ambitious target to increase the share of renewable energy among the total energy mix to be 20%by 2022 and 42%by *** target will be achieved using several approved policies such as feed-in tariffs,build-own-operate and independent power producers under a merchant *** paper presents a full analysis of wind-potential characteristics at Elkharga Oasis in Egypt based on an actual wind-measurement campaign taken by a met mast at two height levels of 10 and 25 m,*** measurements show an average annual wind speed of 5.72 m/s at 10-m height and 6.53 m/s at>25-m *** estimated wind speed,however,is 8.38 m/s at 120 m,which is technically convenient to generate electricity from wind *** this paper,the wind potential in the area is assessed using the statistical method of the Weibull probability density *** different methods to estimate the Weibull distribution parameters are presented and the relevant accuracy is verified based on the root mean square error.A techno-economic assessment and selection of the optimal wind-turbine size with ideal micro-sitings are performed using the software package *** cases of study for three typical wind-turbine models with various rotor diameters,power capacity,layout configuration and annual yield are assessed at the *** selection of the most convenient wind turbine is determined based on the IEC 61400 standard criteria and the turbine that produces the lowest levelized cost of electricity.

关键词： wind energy wind-resource assessment Weibull distribution windPRO levelized cost of electricity

Behavior of raft on settlement reducing piles:Experimental model study

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Journal of Rock Mechanics and Geotechnical Engineering 2013年第5期5卷 389-399页

作者： Basuony El-Garhy ahmed Abdel Galil Abdel-Fattah Youssef mohamed abo Raia Civil Engineering Department Faculty of Engineering Minufiya University

An experimental program is conducted on model piled rafts in sand *** experimental program is aimed to investigate the behavior of raft on settlement reducing *** testing program includes tests on models of single pile,unpiled rafts and rafts on 1,4,9,or 16 *** model piles beneath the rafts are closed ended displacement piles installed by *** lengths of piles are used in the experiments to represent slenderness ratio,L/D,of 20,30 and 50,*** dimensions of the model rafts are 30 cm×30 cm with different thickness of 0.5 cm,1.0 cm or 1.5 *** raft-soil stiffness ratios of the model rafts ranging from 0.39 to 10.56 cover flexible to very stiff *** improvement in the ultimate bearing capacity is represented by the load improvement ratio,LIR,and the reductions in average settlement and differential settlement are represented by the settlement ratio,SR,and the differential settlement ratio,DSR,*** effects of the number of settlement reducing piles,raft relative stiffness,and the slenderness ratio of piles on the load improvement ratio,settlement ratio and differential settlement ratio are presented and *** results of the tests show the effectiveness of using piles as settlement reduction measure with the *** the number of settlement reducing piles increases,the load improvement ratio increases and the differential settlement ratio decreases.

关键词： Raft Settlement reducing piles Piled raft Model tests Sand soil

Ecological risk assessment of surficial sediment by heavy metals from a submerged archaeology harbor,South Mediterranean Sea,Egypt

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Acta Geochimica 2020年第2期39卷 226-235页

作者： Maha ahmed mohamed Abdallah ahmed mohamed Badr-ElDin Marine Pollution Lab National Institute of Oceanography and FisheriesAlexandriaEgypt Oceanography Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt

A protected semi-enclosed embayment,the Eastern Harbor(EH),is situated in the central sector of the Mediterranean coast of Alexandria,*** is a famous fishing dock and water-sport center and its importance arose after the discovery of the Ptolemaic royal quarter of ancient *** protect this national treasure and improve its environmental health,the untreated anthropogenic effluents,which continued for decades into the EH since 1992,must be totally ***,it is an important issue to continually monitor and asses the environmental status of the *** sediment texture,total organic carbon,and the accumulation,distribution,and ecological risks of Cd,Cr,Pb,As,Hg and A1 were determined with a total of 14 surficial sediments samples collected in the EH during *** contents were compared to the literature data to assess the pollution status of *** factors,Degree of contamination(mCd)and potential ecological risk were calculated as a criterion of possible *** mCd calculation produces an overall average value for a range of pollutants,in the present study the contamination factor that provides a measure of the degree of overall contamination in the surface layers in a particular sampling site may provide a better indication of the state of pollution in the EH sediments than other indicators.

关键词： Heavy metals Eastern harbor Enrichment factors Degree of contamination Potential ecological risk

Static and dynamic stability responses of multilayer functionally graded carbon nanotubes reinforced composite nanoplates via quasi 3D nonlocal strain gradient theory

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Defence Technology（防务技术） 2022年第10期18卷 1778-1809页

作者： ahmed Amine Daikh mohamed Sid ahmed Houari mohamed Ouejdi Belarbi Salwa A.mohamed mohamed A.Eltaher Laboratoire D'Etude des Structures et de Mecanique des Materiaux Departement de Genie CivilFacultedes Sciences et de La TechnologieUniversite Mustapha Stambouli B.P.305R.P.29000MascaraAlgeria Laboratoire de Genie Energetique et Materiaux LGEMUniversite de BiskraB.P.145R.P07000BiskraAlgeria Department of Engineering Mathematics Zagazig UniversityP.O.Box 44519ZagazigEgypt Faculty of Engineering Mechanical Engineering DepartmentKing Abdulaziz UniversityP.O.Box 80204JeddahSaudi Arabia Faculty of Engineering Mechanical Design and Production DepartmentZagazig UniversityP.O.Box 44519ZagazigEgypt

This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)*** nanoscale and microstructure influences are considered through a modified nonlocal strain gradient continuum *** on power-law functions,four different patterns of CNTs distribution are considered in this analysis,a uniform distribution UD,FG-V CNTRC,FG-X CNTRC,and FG-O CNTRC.A 3D kinematic shear deformation theory is proposed to include the stretching influence,which is neglected in classical ***'s principle is applied to derive the governing equations of motion and associated boundary *** solutions are developed based on Galerkin method to solve the governing equilibrium equations based on the generalized higher-order shear deformation theory and the nonlocal strain gradient theory and get the static bending,buckling loads,and natural frequencies of *** with previous works is presented.A detailed parametric analysis is carried out to highlight the impact of thickness stretching,length scale parameter(nonlocal),material scale parameter(gradient),CNTs distribution pattern,geometry of the plate,various boundary conditions and the total number of layers on the stresses,deformation,critical buckling loads and vibration *** new results are also reported in the current study,which will serve as a benchmark for future research.

关键词： 3D shear deformation theory Free vibration Buckling Bending Galerkin method Functionally graded nanotube Nonlocal strain gradient theory

Friction and wear of sand-contaminated lubricated sliding

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Friction 2018年第4期6卷 457-463页

作者： mohamed ahmed RAMADAN Faculty of Engineering at Helwan Helwan University

This paper reports a test investigation of friction and wear responses from sand contaminated lubricated sliding. The influence of sand contaminants on wear and friction is characterized. Analyses are completed utilizing segments of piston ring sliding against the cylinder liner. Paraffin oil, with and without sand contaminants, is utilized. The effects of the concentration and particle size of sand are examined. Based on the observations in the present work, we found that friction and wear increase with sand concentration in the lube. Solid proposals ought to be considered, in order to enlighten the general population on the importance of changing a car engine's oil filter regularly.

关键词： sand contamination lubrication oil abrasive wear lubricated sliding

Magnetoresistive properties of Ni-doped La_(0.7)Sr_(0.3)MnO_3 manganites

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Rare Metals 2016年第7期35卷 551-558页

作者： ahmed mohamed ahmed Abd El-Moez ahmed mohamed Medhat Abdelrady Abdellateef Hassan ahmed Abd El-Ghanny Physics Department Faculty of ScienceSohag University

Lao.7Sr0.3Mnl_xNixO3 （x = 0, 0.025, 0.050 and 0.075） ceramics were prepared by the conventional solid-state reaction method. The partial substitution of Mn by Ni2＋ leads to a decrease in cell volume as well as a structural transition from the rhombohedral to the orthorhombic structure. Ni2＋ doping increases the electrical resistivity, decreases the semiconductor-metal transition temperature （Tms） and relatively enhances the room temperature magnetoresistance （MR）, especially in x = 0.025 and around Tins. With respect to conduction mechanism, the small polaron hopping （SPH） and the variable range hopping （VRH） models were used to ex- amine conduction in the semiconducting region.

关键词： Manganites X-ray diffraction Structure Electrical resistivity Magnetoresistance