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A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： muhammed S.PARANCHEERIVILAKKATHIL Jafar S.PILAKKADAN Rafic m.AJAJ mohammadreza AmOOZGAR Davood ASADI yahya ZWEIRI michael I.FRISWELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies morphing aircraft Shape morphing Flight dynamics Aeroelasticity

Classifying modulations in Communication Intelligence Using Deep Learning Networks

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Journal of Systems Science and Information 2024年第3期12卷 379-392页

作者： yahya BENREmDANE Said JAmAL Oumaima TAHERI Jawad LAKZIZ Said OUASKIT Department of Physics Faculty of Science Ben M'sikUniversity HassanⅡCasablanca 20100Morocco

The present research employs artificial intelligence to come up with an automatic solution for the modulation's classification of various radio signal *** a result,the work we performed involved selecting the database required for supervised deep learning,evaluating the performance of current techniques on unprocessed communication signals,and suggesting a deep learning networkbased method that would enable the classification of modulation types with the best possible ratio between computation time and *** started by examining the automatic classification models that are currently in *** light of the difficulty of forecasting in low Signal Noise Ratio(SNR)situations,we suggested an ensemble learning strategy based on adjusted Res Net and Transformer Neural Network,which is effective at extracting multi-scale features from the raw I/Q sequence ***,we produced an architecture that is simple to use and apply to communication *** architecture of this solution is strong and optimal,enabling it to determine the type of modulation with up to 95%accuracy automatically.

关键词： automatic modulation classification artificial intelligence deep learning radio frequency electronicwarfare

Structure-based discovery of *** phytochemicals as potential inhibitors against monkeypox(mpox)viral protein

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Journal of Biosafety and Biosecurity 2024年第3期6卷 157-169页

作者： Ranjan K.mohapatra Ahmed mahal Pranab K.mohapatra Ashish K.Sarangi Snehasish mishra meshari A.Alsuwat Nada N.Alshehri Sozan m.Abdelkhalig mohammed Garout mohammed Aljeldah Ahmad A.Alshehri Ahmed Saif mohammed Abdulrahman Alshahrani Ali S.Alqahtani yahya A.Almutawif Hamza m.A.Eid Faisal m Albaqami mohnad Abdalla Ali A.Rabaan Department of Chemistry Government College of EngineeringKeonjhar 758002OdishaIndia Department of medical Biochemical Analysis College of Health TechnologyCihan University–ErbilErbilKurdistan RegionIraq Department of Chemistry CV Raman Global UniversityBhubaneswarOdishaIndia Department of Chemistry School of Applied SciencesCenturion University of Technology and ManagementBalangirOdishaIndia School of Biotechnology Campus-11KIIT Deemed-to-be-UniversityBhubaneswar 751024OdishaIndia Clinical Laboratory Sciences Department College of Applied Medical SciencesTaif UniversityAl-Taif 21974Saudi Arabia Internal medicine Department King Khalid University Medical CityCollege of MedicineAbha 61481Saudi Arabia Department of Basic medical Sciences College of MedicineAlMaarefa UniversityRiyadhSaudi Arabia Department of Community medicine and Health Care for Pilgrims Faculty of MedicineUmm Al-Qura UniversityMakkah 21955Saudi Arabia Department of Clinical Laboratory Sciences College of Applied Medical SciencesUniversity of Hafr Al BatinHafr Al Batin 39831Saudi Arabia Department of Clinical Laboratory Sciences Faculty of Applied Medical SciencesNajran UniversityNajran 61441Saudi Arabia Department of medical Laboratory Sciences Faculty of Applied Medical SciencesKing Khalid UniversityAbha 61481Saudi Arabia mDepartment of medical Laboratories Technology College of Applied Medical SciencesTaibah UniversityMadinah 41411Saudi Arabia Biology Department College of ScienceIslamic University of MadinahMadinah 42351Saudi Arabia Pediatric Research Institute Children’s Hospital Affiliated to Shandong UniversityJinanShandong 250022China molecular Diagnostic Laboratory Johns Hopkins Aramco HealthcareDhahran 31311Saudi Arabia College of medicine Alfaisal UniversityRiyadh 11533Saudi Arabia Department of Public Health and Nutrition The University of HaripurHaripur 22610Pakistan

Outbreaks of monkeypox(mpox)in over 100 non-endemic countries in 2022 represented a serious global health *** a neglected disease,mpox has become a global public health issue.A42R profilinlike protein from mpox(PDB ID:4QWO)represents a potential new lead for drug development and may interact with various synthetic and natural *** this report,the interaction of A42R profilinlike protein with six phytochemicals found in the medicinal plant Ficus religiosa(abundant in India)was *** on the predicted and compared protein–ligand binding energies,biological properties,IC_(50) values and toxicity,two compounds,kaempferol(C-1)and piperine(C-4),were *** characteristics and quantitative structure–activity relationship(QSAR)of these two compounds were determined,and molecular dynamics(mD)simulations were *** silico examination of the kaempferol(C-1)and piperine(C-4)interactions with A42R profilin-like protein gave best-pose ligandbinding energies of–6.98 and–5.57 kcal/mol,*** predicted IC_(50) of C-1 was 7.63 lm and 82 lm for *** data indicated that kaempferol and piperine are non-mutagenic,and the QSAR data revealed that piperlongumine(5.92)and piperine(5.25)had higher log P values than the other compounds *** simulations of A42R profilin-like protein in complex with C-1 and C-4 were performed to examine the stability of the ligand–protein ***/C and C-4 showed the highest affinity and activities,they may be suitable lead candidates for developing mpox therapeutic *** study should facilitate discovering and synthesizing innovative therapeutics to address other infectious diseases.

关键词： monkeypox mpox Phytochemical molecular docking mD simulation ADmET QSAR

Spinal dural arteriovenous fistula:a comprehensive review of the history,classification systems,management,and prognosis

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Chinese Neurosurgical Journal 2024年第1期10卷 48-56页

作者： Ali Alkhaibary Ahoud Alharbi Nada Alnefaie Hajar Alammar Alshaymaa m.Arishy Noor Alghanim Yazeed m.Aldhfyan Arwa Albaiahy yahya H.Khormi Wael Alshaya Saad AlQahatani Ahmed Aloraidi Ahmed Alkhani Sami Khairy College of medicine King Saud Bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia King Abdullah International medical Research Center RiyadhSaudi Arabia Division of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityMinistry of National Guard-Health AffairsRiyadhSaudi Arabia Department of Neurosurgery National Neurosciences InstituteKing Fahad Medical CityRiyadhSaudi Arabia College of medicine Jazan UniversityJazanSaudi Arabia Department of Neurosurgery King Faisal Specialist Hospital and Research CenterRiyadhSaudi Arabia Department of Surgery Faculty of MedicineJazan UniversityJazanSaudi Arabia

Spinal dural arteriovenous fistulas account for the majority of spinal vascular *** are typically located in the thoracolumbar region and are diagnosed in the middle-aged and elderly *** spinal dural arteriovenous fistulas have been postulated to be acquired,their exact development remains ***,the arteriovenous shunt is situated close to the spinal nerve root,inside the dura mater,where the blood from the radiculomeningeal artery and radicular vein *** history,there have been multiple classification systems of spinal arteriovenous shunts since *** were mainly based on the evolution of diagnostic studies as well as the treatment of these *** classification systems have undergone significant changes over the *** intracranial dural arteriovenous fistula,spinal dural arteriovenous fistula is progressive in *** neurological manifestations,due to venous congestion,tend to be insidious as well as *** include sensory deficits,such as paresthesia,bilateral and/or unilateral radicular pain affecting the lower limbs,and gait *** dural arteriovenous fistulas can be suspected on magnetic resonance imaging/magnetic resonance angiography and confirmed by digital subtraction angiography(DSA).The management includes surgery,endovascular therapy,and in selected cases,*** treatment goal of spinal dural arteriovenous fistula is to halt the progression of the *** prognosis depends on both the duration of symptoms as well as the clinical condition prior to *** present article comprehensively reviews the pathophysiology,changes in classification systems,natural history,clinical manifestations,radiological features,management,and prognosis.

关键词： Connection Endovascular myelopathy Vascular

Catalytic effect of SrTiO_3 on the hydrogen storage behaviour of mgH_2

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Journal of Energy Chemistry 2019年第1期28卷 46-53页

作者： m.S.yahya m.Ismail School of Ocean Engineering University Malaysia Terengganu

The effects of Sr TiO_3 on the hydrogen storage properties of mgH_2 have been studied for the first *** onset dehydrogenation temperature of the mgH_2-10 wt% SrTiO_3 is found to be 275 ℃, which is 55 ℃ lower as compared to the as-milled mgH_2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled mg H_2. meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled mg H_2 at 320 ℃. The calculated Eaof the mg H_2-10 wt% SrTiO_3 is 109 k J/mol, which is 26.3 kJ/mol lower than the calculated Eaof the as-milled mgH_2. The Sr TiO_3 is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the SrTiO_3 is owing to its ability to change the physical structure of the mgH_2 particles during the ball milling process.

关键词： Hydrogen storage magnesium hydride Catalytic effect Sorption properties

Thermal stresses in infinite circular cylinder subjected to rotation

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Applied mathematics and mechanics(English Edition) 2012年第8期33卷 1059-1078页

作者： A.m.ABD-ALLA G.A.yahya Department of mathematics Faculty of ScienceTaif UniversitySaudi Arabia Department of Physics Faculty of ScienceTaif UniversitySaudi Arabia Department of Physics Faculty of ScienceAswan UniversityAswan 81528AswanEgypt

The present investigation is concerned with the effect of rotation on an infi- nite circular cylinder subjected to certain boundary conditions. An analytical procedure for evaluation of thermal stresses, displacements, and temperature in rotating cylinder subjected to thermal load along the radius is presented. The dynamic thermal stresses in an infinite elastic cylinder of radius a due to a constant temperature applied to a variable portion of the curved surface while the rest of surface is maintained at zero temperature are discussed. Such situation can arise due to melting of insulating material deposited on the surface cylinder. A solution and numerical results are obtained for the stress components, displacement components, and temperature. The results obtained from the present semi-analytical method are in good agreement with those obtained by using the previously developed methods.

关键词： wave propagation thermoelasticity isotropic material rotating cylinder Lam’e potential thermal stress

Effect of (Ba_(0.6)Sr_(0.4))TiO_3(BST) Doping on Dielectric Properties of CaCu_3Ti_4O_(12)(CCTO)

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Journal of materials Science & Technology 2012年第12期28卷 1137-1144页

作者： I. Norezan A.K. yahya m.K. Talari Faculty of Applied Sciences Universiti Teknologi MARAShah Alam Selangor Malaysia

The effect of （Ba（0.6）Sr（0.4））TiO3（BST） addition on dielectric properties of CaCu3Ti4O（12）（CCTO） ceramic was investigated. Ceramic samples with the chemical formula （1-x）CaCu3Ti4O（12）＋ x（Ba（0.6）,Sr（0.4））TiO3 （x=0, 0.05, 0.1, and 0.2） were synthesized from high purity oxide powders by the conventional solid-state synthesis method. X-ray diffraction （XRD） analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron microscopy （SEm） investigation showed a slight decrease in grain size of doped CCTO samples. Density measurements showed that porosity content increased with increasing BST addition indicating low densification due to high melting point secondary phase addition. Dielectric constant of undoped CCTO （x=0） showed lack of stability with frequency which dropped drastically between 104 and 105Hz and accompanied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but improved stability with frequency compared to the undoped sample. The decrease in dielectric constant of doped CCTO samples was suggested to be partly due to the decrease in average grain size and increase in porosity with BST addition. Nevertheless, a high value of dielectric constant was still maintained around ～104 range for all doped samples. The dielectric loss （tanδ） of all BST-doped samples was lower than that of pure CCTO sample at the frequency range of 103 to 105 Hz probably due to the increase of grains boundary resistivity. The activation energy of grains boundary （E（gb）） showed higher values as compared to the activation energy of grains （Eg ） for all samples and conforms to the internal barrier layer capacitor （IBLC） model.

关键词： CaCu3Ti4O(12)(CCTO) Dielectric properties (Ba(0.6)Sr(0.4))TiO3(BST)

Effects of Increasing Tungsten on Structural,Elastic and Optical Properties of xWO_3-(40-x)Ag_2O-60Te_2O Glass System

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Journal of materials Science & Technology 2015年第1期31卷 83-90页

作者： mm.Umair A.K.yahya m.K.Halimah H.A.A.Sidek School of Physics and materials Studies Universiti Teknologi MARA Department of Physics Faculty of ScienceUniversiti Putra Malaysia

Ternary teiiurite glasses with composition of xWO3（40-x）Ag2O-60TeO2（x=0-40 mol%） have been prepared by melt-quenching *** and optical properties of the glass system were obtained by ultrasonic velocity measurements and UV-vis spectroscopy,respectively,while structural investigation was carried out by using Raman *** longitudinal and shear velocities,vLand vsshowed large increase at x from 0 to 20 mol%before decrease with further addition of *** longitudinal modulus CLand shear modulus μ bulk modulus KeYoung’s modulus Vand Debye temperature θDshowed similar behaviors to both *** large increase of the elastic moduli at x from 0 to 20 mol%is suggested to be due to the increase in WO6octahedral unit structure indicating the increase of bridging oxygen（BO） and formation of stronger Te-O-W bonds compared to Te-O-Te *** the other hand,forx> 20 mol%,the decrease in the elastic moduli was due to the increase of non-bridging oxygen（NBO） as a result of formation of WO4tetrahedral via breaking Te-O-W *** analysis by using bulk compression and ring deformation models showed a slight decrease in the ratio of ideal bulk modulus Kbcto the experimental bulk modulus Keand average atomic ring size,/ for×mol%followed by a large increase for x > 20 mol%.Our analysis also indicates that limited ring deformation took place and the main compression mechanism in this glass system was mainly ideal isotropic *** the other hand,optical band gap Eoptshowed small variation for x=0-20 mol%but decreased upon higher WO3content while refractive index n showed the opposite *** optical behavior is suggested to be related to the changes in cross link density and NBO concentration in the glass system.

关键词： Elastic moduli Optical absorption Raman spectrosco

Theoretical and experimental research on effect of fins attachment on operating parameters and thermal efficiency of solar air collector

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Information Processing in Agriculture 2018年第4期5卷 411-421页

作者： Ali Daliran yahya Ajabshirchi Department of Agricultural machinery University of TabrizTabrizIran

Flat plate air collector is a type of heat exchanger which absorbs radiated solar energy and exchanges it to *** to low efficiency of this type of collectors,a suitable approach is investigated in this paper so as to increase thermal performance of the *** efficiency of solar collector for two models C1(without fins)and C2(with fins)both of 1 m^2 surface area with forced convection flow is studied theoretically and *** fins are attached over back board in air channel to create turbulence in air *** order to measure air temperature,17 thermal sensors(Lm35)are exploited,among which 11 were mounted on absorber plate and the remaining 6 on the back *** design of experimental model are performed in Solidwork and programming of theoretical work in matlab *** this research,a fan with constant mass flow rate of 0.033 kg/s is utilized for producing air *** indicate that applying fins in air channel not only reduces Nusselt number from 19.67 to 16.23,but also due to decreasing hydraulic diameter and creating air flow turbulence,causes increase of heat transfer coefficient from absorber plate to air flow and consequently reduction of total heat loss and higher outlet air *** difference of outlet air temperature between experimental and theoretical results for both collectors(C1 and C2)was recorded respectively as 7.6% and 9.4%.Thermal efficiency was respectively calculated 30% and 51% for experimental types with and without fins and 33% and 55% for those of theoretical work which generally seem reasonable.

关键词： Solar air collector Fins Thermal efficiency Energy efficiency Renewable energy