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New Antenna Array Beamforming Techniques Based on Hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications

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Computer modeling in Engineering & Sciences 2024年第3期138卷 2749-2767页

作者： Shimaa m.Amer Ashraf A.m.Khalaf amr H.Hussein Salman A.Alqahtani mostafa H.Dahshan Hossam m.Kassem Electronics and Communications Engineering Department Higher Institute of Engineering and TechnologyKafr ElsheikhEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringHorus University EgyptNew DamiettaEgypt Department of Computer Engineering College of computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia School of Computing Mathematics and EngineeringCharles Sturt UniversityBathurstNSW2795Australia

Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to ***,it improves the array gain and directivity,increasing the detection range and angular resolution of radar *** study proposes two highly efficient SLL reduction *** techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,*** convolution process determines the element’s excitations while the GA optimizes the element *** m elements linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length N=(2m−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths m,m−1,andm,*** the same element spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(HPBW).While the middle excitations give the same HPBWas the original LAA with a relatively higher *** the increased HPBWof the odd and even excitations,the element spacing is optimized using the ***,the synthesized arrays have the same HPBW as the original LAA with a two-fold reduction in the ***,for extreme SLL reduction,the DConv/GA is *** this technique,the same procedure of the aforementioned Conv/GA technique is performed on the resultant even and odd excitation *** provides a relatively wider HPBWthan the original LAA with about quad-fold reduction in the SLL.

关键词： Array synthesis convolution process genetic algorithm(GA) half power beamwidth(HPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(QOS)

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multi-timescale modeling and Dynamic Stability Analysis for Sustainable microgrids:State-of-the-art and Perspectives

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Protection and Control of modern Power Systems 2024年第3期9卷 1-35页

作者： mingyue Zhang Yang Han Yuxiang Liu amr S.Zalhaf Ensheng Zhao Karar mahmoud mohamed m.F.Darwish Frede Blaabjerg the School of mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China IEEE 不详 the University of Electronic Science and Technology of China(UESTC) ChengduChina Aswan University the School of Electrical Engineering Aalto UniversityFinland the Department of Electrical Engineering Faculty of Engineering at ShoubraBenha University the Department of EEA School of Electrical EngineeringAalto University

The increasing trend for integrating renewable energy sources into the grid to achieve a cleaner energy system is one of the main reasons for the development of sustainable microgrid(mG)*** typical power-electronized power systems,mGs make extensive use of power electronics converters,which are highly controllable and flexible but lead to a profound impact on the dynamic performance of the whole *** with traditional large-capacity power systems,mGs are less resistant to perturbations,and various dynamic variables are coupled with each other on multiple timescales,resulting in a more complex system instability *** meet the technical and economic challenges,such as active and reactive power-sharing,voltage,and frequency deviations,and imbalances between power supply and demand,the concept of hierarchical control has been introduced into mGs,allowing systems to control and manage the high capacity of renewable energy sources and ***,as the capacity and scale of the mG system increase,along with a multi-timescale control loop design,the multi-timescale interactions in the system may become more significant,posing a serious threat to its safe and stable *** investigate the multi-timescale behaviors and instability mechanisms under dynamic inter-actions for AC mGs,existing coordinated control strategies are discussed,and the dynamic stability of the system is defined and classified in this ***,the modeling and assessment methods for the stability analysis of multi-timescale systems are also ***,an outlook and discussion of future research directions for AC mGs are also presented.

关键词： Sustainable microgrid hierarchical control modeling model simplification multi-timescale dynamic stability analysis timescale decomposition.

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Synergistic inhibition effect of poly(ethylene glycol) and cetyltrimethylammonium bromide on corrosion of Zn and Zn-Ni alloys for alkaline batteries

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Transactions of Nonferrous metals Society of China 2020年第1期30卷 259-274页

作者： Hany m.abd EL-LATEEF mahmoud ELROUBY Department of Chemistry Faculty of ScienceSohag UniversitySohag 82524Egypt Department of Chemistry College of ScienceKing Faisal UniversityP.O.Box 380 Al Hofuf 31982 Al-HassaSaudi Arabia

The synergistic inhibition effect of poly(ethylene glycol)-400(PEG-400)and cetyltrimethylammonium bromide(CTmAB)on the corrosion of Zn and Zn-Ni alloys in 8 mol/L KOH solution saturated with Zn O was observed by potentiodynamic anodic/cathodic polarization(PDP),and electrochemical impedance spectroscopy(EIS)*** electrochemical studies confirmed that there was a synergism between PEG-400 and CTmAB on corrosion inhibition of Zn and its *** inhibition efficiency of the mixed inhibitors,250 mg/L CTmAB+250 mg/L PEG-400,was found to be much higher than that of the single inhibitor,500 mg/L PEG-400 or 500 mg/L *** electron microscopic(SEm)investigations before and after the corrosion inhibition process emphasize the synergistic effect of the mixed ***,it was found that the addition of the investigated inhibitors to the alkaline solution enhanced the discharge and capacity of the alkaline battery *** obtained electrochemical data exhibited a good correlation with the computational one.

关键词： synergistic effect corrosion inhibition Zn-Ni alloy alkaline batteries

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microstructural study and numerical simulation of phase decomposition of heat treated Co–Cu alloys

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Progress in Natural Science:materials International 2014年第6期24卷 599-607页

作者： A.m.mebed Alaa m.abd-Elnaiem Department of Physics Faculty of Science Assiut University Department of Physics Faculty of Science Aljouf University

The influence of heat treatment on the phase decomposition and the grain size of Co–10 at% Cu alloy were studied. Few samples were aged in a furnace for either 3 or 5 h and then quenched in iced water. The materials and phase compositions were investigated using energy dispersive spectrometry and X-ray diffraction techniques. X-ray diffraction analysis showed that the samples contained Co, Cu, Cu O, Co Cu2O3, Co Cu O2 phases in different proportions depending on the heat treatment regimes. The formation of dendrite Co phase rendered the spinodal decomposition while the oxidations prevent the initiation of the spinodal decomposition even for a deep long aging inside the miscibility *** the Bragg reflections from different phases of Co–Cu alloy significantly overlap, the crystal structural parameters were refined with FULLPROF program. The shifts in the refined lattice constants(a, b and c), the space group and the grain size were found to be phase- and heat treatment-dependant. Two-dimensional computer simulations were conducted to study the phase decomposition of Co–Cu binary alloy *** excess free energy as well as the strain energy, without a priori knowledge of the shape or the position of the new phase, was precisely evaluated. The results indicate that the morphology and the shape of the microstructure agree with SEm observation.

关键词： Co–Cu alloys Phase decomposition X-Ray diffraction Rietveld analysis Computer simulation

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New Polymer Syntheses Part 60: A Facile Synthetic Route to Polyamides Based on Thieno[2,3-b]thiophene and Their Corrosion Inhibition Behavior

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Chinese Journal of Polymer Science 2018年第7期36卷 835-847页

作者： Kamal I.Aly amr H.moustafa Essam K.Ahmed Hany m.abd El-lateef mohamed Gamal mohamed Sahar m.mohamed Polymer Research Lab Chemistry Department Faculty of Science Assiut University Chemistry Department Faculty of Science Sohag University Chemistry Department Faculty of Science Minia University Chemistry Department College of Science King Faisal university

Polyamides containing thieno[2,3-b]thiophene moiety were prepared via a simple polycondensation reaction of the diaminothieno[2,3-b]thiophene monomer la with different kinds of diacid chlorides （including oxalyl, adipoyl, sebacoyl, isophthaloyl, terephthaloyl, 4,4＇-azodibenzoyl, 3,3＇-azodibenzoyl, p-phenylene diacryloyl） in the presence of LiC1 and NmP as a solvent through lowtemperature solution polycondensation. The chemical structures of model compound and synthesized polyamides were confirmed by FTIR, nuclear magnetic resonance spectroscopy （including 1 H-NmR and 13 C-NmR） and elemental analysis. In addition, the thermal stability, crystallinity structure and surface morphology of synthesized polyamides were characterized via thermogravametric analysis （TGA）, wide-angle X-ray diffraction analysis （WAXD） and scanning electron microscopy （SEm）. Also, the corrosion inhibition behavior of selected examples ofpolyamides was investigated; the inhibitive effect of the investigated polymers for carbon steel in 1.0 mol＇L-1 HCI was studied using potentiodynamic polarization （PDP） and electrochemical impedance spectroscopy （EIS） methods. PDP results displayed that the polyamides containing thieno[2,3-b]thiophene moiety can be as mixed-type inhibitors. The inhibition efficiency （P, %） was found to be in the range from 67.13% to 96.01%. There is an increase in P by the synthesized polymers in comparison to the starting monomer. The adsorption of these polymers was found to obey Langmuir adsorption isotherm.

关键词： Thieno[2 3-b]thiophene Polymer synthesis Thermal properties Industrial applications Corrosion inhibition

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An Efficient Indoor Localization Based on Deep Attention Learning model

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Computer Systems Science & Engineering 2023年第8期46卷 2637-2650页

作者： amr Abozeid Ahmed I.Taloba Rasha m.abd El-Aziz Alhanoof Faiz Alwaghid mostafa Salem Ahmed Elhadad Department of Computer Science College of Science and ArtsJouf UniversityQurayyatSaudi Arabia Information System Department Faculty of Computers and InformationAssiut UniversityEgypt Computer Science Department Faculty of Computers and InformationAssiut UniversityAssiutEgypt Department of Computer Science Faculty of Computers and InformationSouth Valley UniversityQenaEgypt

Indoor localization methods can help many sectors,such as healthcare centers,smart homes,museums,warehouses,and retail malls,improve their service *** a result,it is crucial to look for low-cost methods that can provide exact localization in indoor *** this context,imagebased localization methods can play an important role in estimating both the position and the orientation of cameras regarding an ***-based localization faces many issues,such as image scale and rotation ***,image-based localization’s accuracy and speed(latency)are two critical *** paper proposes an efficient 6-DoF deep-learning model for image-based *** model incorporates the channel attention module and the Scale Pyramidmodule(SPm).It not only enhances accuracy but also ensures the model’s real-time *** complex scenes,a channel attention module is employed to distinguish between the textures of the foregrounds and *** model adapted an SPm,a feature pyramid module for dealing with image scale and rotation variance ***,the proposed model employs two regressions(two fully connected layers),one for position and the other for orientation,which increases outcome *** on standard indoor and outdoor datasets show that the proposed model has a significantly lower mean Squared Error(mSE)for both position and *** the indoor 7-Scenes dataset,the mSE for the position is reduced to 0.19 m and 6.25°for the ***,on the outdoor Cambridge landmarks dataset,the mSE for the position is reduced to 0.63 m and 2.03°for the *** to the findings,the proposed approach is superior and more successful than the baseline methods.

关键词： Image-based localization computer vision deep learning attention module VGG-16

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Plant phosphatidylinositol-specific phospholipase C at the center of plant innate immunity

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Journal of Integrative Plant Biology 2017年第3期59卷 164-179页

作者： Ahmed m.abd-El-Haliem matthieu H.A.J.Joosten Laboratory of Phytopathology Wageningen University Droevendaalsesteeg 1 6708 PB Wageningen The Netherlands Plant Physiology Swammerdam Institute for Life Sciences University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands

Understanding plant resistance to pathogenic microbes requires detailed information on the molecular mechanisms controlling the execution of plant innate immune responses. A growing body of evidence places phosphoinositide-specific phospholipase C （PI-PLC） en- zymes immediately downstream of activated immune receptors, well upstream of the initiation of early defense responses. An increase of the cytoplasmic levels of free Ca2＋, lowering of the intercellular pH and the oxidative burst are a few examples of such responses and these areregulated by PI-PLCs. Consequently, PI-PLC activation represents an early primary signaling switch between elicitation and response involving the controlled hydrolysis of essential signaling phospholipids, thereby simulta- neously generating lipid and non-lipid second messenger molecules required for a swift cellular defense response. Here, we elaborate on the signals generated by PI-PLCs and their respective downstream effects, while providing an inventory of different types of evidence describing the involvement of PI-PLCs in various aspects of plant immunity. We project the discussed information into a model describing the cellular events occurring after the activation of plant immune receptors. With this review we aim to provide new insights supporting future research on plant PI-PLCs and the development of plants with improved resistance.

关键词： Pradeep Kachroo University of Kentucky USA

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Does dutasteride reduce the bleeding in transurethral resection of the prostate in patients on antiplatelet drugs?

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Current Urology 2024年第3期18卷 194-198页

作者： Ahmed m.Rammah Alaa meshref Ebram Soliman Islam Nasser abd Elaziz Enmar Habib Ahmed Yehia abdelaziz Ahmed H.Abozamel Department of Urology Kasr Alainy HospitalFaculty of MedicineCairo UniversityCairoEgypt El Sahel Teaching Hospital CairoEgypt

Background The aim of this study was to assess the effect of a 4-week dutasteride treatment on reducing the intraoperative and postoperative bleeding,as well as the amount and duration of irrigation required to clear the urine after transurethral resection of the prostate(TURP)≥50 g in men receiving the antiplatelet drug(APD).materials and methods This double-blind randomized clinical trial included patients with a prostate size≥50 g who were indicated for TURP and were already receiving *** study was conducted in the Urology Department of Cairo University over a 12-month *** preoperative laboratory investigations were performed in all ***,baseline prostate size,serum prostate-specific antigen level,and International Prostate Symptom Score were *** patients were randomly divided into 2 equal groups(groups A and B).Group A,the dutasteride group,received dutasteride(0.5 mg)once daily for 4 *** B,the placebo group,received a placebo capsule once daily for 4 *** groups underwent bipolar *** patients were excluded from the study;9 patients from group A and 6 patients from group B,either due to drug intolerability or loss *** The mean blood loss was insignificant between the 2 groups immediately after and 24 hours after surgery(Δhemoglobin:1.41±0.63 g/dL vs.1.48±0.54 g/dL,2.12±0.70 g/dL vs.2.31±0.78 g/dL,respectively,p=0.631,p=0.333;Δhematocrit:2.97%±1.51%vs.3.16%±1.36%,4.96%±1.87%vs.5.73%±4.39%,respectively,p=0.610,p=0.380).However,there were significant differences in duration of indwelling urethral catheter(5.10±0.55 days vs.5.80±1.79 days,p=0.048),duration of bladder irrigation(13.60±2.85 hours vs.16.33±6.62 hours,p=0.044),and the amount of saline used for bladder irrigation(11.03±2.30 L vs.13.87±6.13 L,p=0.046)between group A and group *** Treatment with dutasteride for 4 weeks before TURP in men receiving APD did not significantly reduce intraoperative or postoperativ

关键词： Dutasteride Transurethral resection of the prostate Postprostatectomy bleeding Antiplatelet drugs

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The influence of Thomson effect and inclined loads in an electro-magneto-thermoelastic solid with voids under green-Naghdi theories

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Journal of Ocean Engineering and Science 2018年第3期3卷 253-264页

作者： Elsayed m.abd-Elaziz mohamed I.m.Hilal Department of mathematics Zagazig UniversityFaculty of ScienceP.O.Box 44519ZagazigEgypt

The present investigation deals with the 2-dimensional deformation in a homogeneous thermoelastic solid with voids subjected to inclined *** heat conduction equation is affected with the Thomson *** basic governing equations are modified by using Green-Naghdi theory of *** normal mode analysis technique is used to obtain the components of stress,strain,temperature,induced magnetic field and change in volume fraction *** variations of these quantities have been depicted graphically in the Green-Naghdi theories of type-II and III for an insulated *** numerical calculations,the effect of Thomson parameter and angle of inclination on a homogeneous,isotropic,electro-magneto-thermoelastic material with voids is revealed and discussed.

关键词： Electro-magneto-thermoelasticity Normal mode method Inclined loads Voids Thomson effect Green-Naghdi theory

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ON THE COEFFICIENTS OF DIFFERENTIATED EXPANSIONS AND DERIVATIVES OF CHEBYSHEV POLYNOmIALS OF THE THIRD AND FOURTH KINDS

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Acta mathematica Scientia 2015年第2期35卷 326-338页

作者： Eid H.DOHA Waleed m.abd-ELHAmEED mahmoud A.BASSUONY Department of mathematics Faculty of ScienceCairo University Department of mathematics Faculty of ScienceUniversity of Jeddah Department of mathematics Faculty of ScienceFayoum University

Two new analytical formulae expressing explicitly the derivatives of Chebyshev polynomials of the third and fourth kinds of any degree and of any order in terms of Chebyshev polynomials of the third and fourth kinds themselves are proved. Two other explicit formulae which express the third and fourth kinds Chebyshev expansion coefficients of a general-order derivative of an infinitely differentiable function in terms of their original expansion coefficients are also given. Two new reduction formulae for summing some terminating hypergeometric functions of unit argument are deduced. As an application of how to use Chebyshev polynomials of the third and fourth kinds for solving high-order boundary value problems, two spectral Galerkin numerical solutions of a special linear twelfth-order boundary value problem are given.

关键词： Chebyshev polynomials of the third and fourth kinds expansion coefficients generalized hypergeometric functions boundary value problems

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