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A review of control strategies used for m.rphing aircraft applications

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

作者： m.ham.ed S.PARANCHEERIVILAKKATHIL Jafar S.PILAKKADAN Rafic m.AJAJ m.ham.adreza Am.OZGAR Davood ASADI yahya ZWEIRI m.chael I.FRISWELL Departm.nt of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Departm.nt of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Departm.nt of m.chanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Departm.nt of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithm. and strategies used for fixed-wing m.rphing aircraft applications. It is evident from.the literature that the developm.nt of control algorithm. for m.rphing aircraft technologies focused on three m.in areas. The first area is related to precise control of the shape of m.rphing concepts for various flight conditions. The second area is m.inly related to the flight dynam.cs, stability, and control aspects of m.rphing aircraft. The third area deals m.inly with aeroelastic control using m.rphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for m.rphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynam.c, 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 com.unity is in strong need of such a critical review especially as m.rphing aircraft technologies m.ve from.fundam.ntal research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aim. 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.sim.le Proportional Integral Derivative(PID) controllers at one end to com.lex robust adaptive controllers and deep learning algorithm. at the other end. This includes analytical, com.utational, and experim.ntal studies. In addition, the various dynam.c m.dels used and their fidelities are highlighted and discussed.

关键词： Control strategies m.rphing aircraft Shape m.rphing Flight dynam.cs Aeroelasticity

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Classifying m.dulations in Com.unication Intelligence Using Deep Learning Networks

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Journal of System. Science and Inform.tion 2024年第3期12卷 379-392页

作者： yahya BENREm.ANE Said JAm.L Oum.im. TAHERI Jawad LAKZIZ Said OUASKIT Departm.nt of Physics Faculty of Science Ben M'sikUniversity HassanⅡCasablanca 20100Morocco

The present research em.loys artificial intelligence to com. up with an autom.tic solution for the m.dulation's classification of various radio signal *** a result,the work we perform.d involved selecting the database required for supervised deep learning,evaluating the perform.nce of current techniques on unprocessed com.unication signals,and suggesting a deep learning networkbased m.thod that would enable the classification of m.dulation types with the best possible ratio between com.utation tim. and *** started by exam.ning the autom.tic classification m.dels that are currently in *** light of the difficulty of forecasting in low Signal Noise Ratio(SNR)situations,we suggested an ensem.le learning strategy based on adjusted Res Net and Transform.r Neural Network,which is effective at extracting m.lti-scale features from.the raw I/Q sequence ***,we produced an architecture that is sim.le to use and apply to com.unication *** architecture of this solution is strong and optim.l,enabling it to determ.ne the type of m.dulation with up to 95%accuracy autom.tically.

关键词： autom.tic m.dulation classification artificial intelligence deep learning radio frequency electronicwarfare

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Catalytic effect of SrTiO_3 on the hydrogen storage behaviour of m.H_2

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Journal of Energy Chem.stry 2019年第1期28卷 46-53页

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

The effects of Sr TiO_3 on the hydrogen storage properties of m.H_2 have been studied for the first *** onset dehydrogenation tem.erature of the m.H_2-10 wt% SrTiO_3 is found to be 275 ℃, which is 55 ℃ lower as com.ared to the as-m.lled m.H_2. The com.osite is able to absorb 4.3 wt% of hydrogen in 60 m.n instead of 1.1 wt% for the as-m.lled m. H_2. m.anwhile, the com.osite is able to release 5.3 wt% of hydrogen in 17 m.n com.ared to 1.9 wt% by the as-m.lled m. H_2 at 320 ℃. The calculated Eaof the m. H_2-10 wt% SrTiO_3 is 109 k J/m.l, which is 26.3 kJ/m.l lower than the calculated Eaof the as-m.lled m.H_2. The Sr TiO_3 is not decom.osed during the ball m.lling 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 m.H_2 particles during the ball m.lling process.

关键词： Hydrogen storage m.gnesium hydride Catalytic effect Sorption properties

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Im.act of device resistances in the perform.nce of graphene-based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期 89-99页

作者： óscar Castelló Sofía m.López Baptista Kenji Watanabe Takashi Taniguchi Enrique Diez Jesús Enrique Velázquez-Pérez yahya m.m.ziani José m.Caridad Juan A.Delgado-Notario Departm.nt of Applied Physics University of Salamanca Unidad de Excelencia en Luz y m.teria Estructurada(LUm.S) University of Salamanca Research Center for Electronic and Optical m.terials National Institute for Materials Science Research Center for m.terials Nanoarchitectonics National Institute for Materials Science Nanotechnology Group USAL–Nanolab University of Salamanca

In recent years, graphene field-effect-transistors(GFETs) have dem.nstrated an outstanding potential for terahertz(THz) photodetection due to their fast response and high-sensitivity. Such features are essential to enable em.rging THz applications, including 6G wireless com.unications, quantum.inform.tion, bioim.ging and security. However, the overall perform.nce of these photodetectors m.y be utterly com.rom.sed by the im.act of internal resistances presented in the device, so-called access or parasitic resistances. In this work, we provide a detailed study of the influence of internal device resistances in the photoresponse of high-m.bility dual-gate GFET detectors. Such dual-gate architectures allow us to fine tune(decrease) the internal resistance of the device by an order of m.gnitude and consequently dem.nstrate an im.roved responsivity and noise-equivalent-power values of the photodetector, respectively. Our results can be well understood by a series resistance m.del, as shown by the excellent agreem.nt found between the experim.ntal data and theoretical calculations. These findings are therefore relevant to understand and im.rove the overall perform.nce of existing high-m.bility graphene photodetectors.

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Spinal dural arteriovenous fistula:a com.rehensive review of the history,classification system.,m.nagem.nt,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 Alam.ar alshaym.a m.Arishy Noor Alghanim.Yazeed m.Aldhfyan Arwa Albaiahy yahya H.Khorm. Wael alshaya Saad AlQahatani Ahm.d Aloraidi Ahm.d Alkhani Sam. Khairy College of m.dicine King Saud Bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia King Abdullah International m.dical Research Center RiyadhSaudi Arabia Division of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityMinistry of National Guard-Health AffairsRiyadhSaudi Arabia Departm.nt of Neurosurgery National Neurosciences InstituteKing Fahad Medical CityRiyadhSaudi Arabia College of m.dicine Jazan UniversityJazanSaudi Arabia Departm.nt of Neurosurgery King Faisal Specialist Hospital and Research CenterRiyadhSaudi Arabia Departm.nt of Surgery Faculty of MedicineJazan UniversityJazanSaudi Arabia

Spinal dural arteriovenous fistulas account for the m.jority of spinal vascular *** are typically located in the thoracolum.ar region and are diagnosed in the m.ddle-aged and elderly *** spinal dural arteriovenous fistulas have been postulated to be acquired,their exact developm.nt rem.ins ***,the arteriovenous shunt is situated close to the spinal nerve root,inside the dura m.ter,where the blood from.the radiculom.ningeal artery and radicular vein *** history,there have been m.ltiple classification system. of spinal arteriovenous shunts since *** were m.inly based on the evolution of diagnostic studies as well as the treatm.nt of these *** classification system. have undergone significant changes over the *** intracranial dural arteriovenous fistula,spinal dural arteriovenous fistula is progressive in *** neurological m.nifestations,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 lim.s,and gait *** dural arteriovenous fistulas can be suspected on m.gnetic resonance im.ging/m.gnetic resonance angiography and confirm.d by digital subtraction angiography(DSA).The m.nagem.nt includes surgery,endovascular therapy,and in selected cases,*** treatm.nt goal of spinal dural arteriovenous fistula is to halt the progression of the *** prognosis depends on both the duration of sym.tom. as well as the clinical condition prior to *** present article com.rehensively reviews the pathophysiology,changes in classification system.,natural history,clinical m.nifestations,radiological features,m.nagem.nt,and prognosis.

关键词： Connection Endovascular m.elopathy Vascular

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Therm.l stresses in infinite circular cylinder subjected to rotation

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Applied m.them.tics and m.chanics(English Edition) 2012年第8期33卷 1059-1078页

作者： A.m.ABD-ALLA G.A.yahya Departm.nt of m.them.tics Faculty of ScienceTaif UniversitySaudi Arabia Departm.nt of Physics Faculty of ScienceTaif UniversitySaudi Arabia Departm.nt 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 therm.l stresses, displacem.nts, and tem.erature in rotating cylinder subjected to therm.l load along the radius is presented. The dynam.c therm.l stresses in an infinite elastic cylinder of radius a due to a constant tem.erature applied to a variable portion of the curved surface while the rest of surface is m.intained at zero tem.erature are discussed. Such situation can arise due to m.lting of insulating m.terial deposited on the surface cylinder. A solution and num.rical results are obtained for the stress com.onents, displacem.nt com.onents, and tem.erature. The results obtained from.the present sem.-analytical m.thod are in good agreem.nt with those obtained by using the previously developed m.thods.

关键词： wave propagation therm.elasticity isotropic m.terial rotating cylinder Lam.e potential therm.l stress

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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 m.terials 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） ceram.c was investigated. Ceram.c sam.les with the chem.cal form.la （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 m.thod. X-ray diffraction （XRD） analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron m.croscopy （SEm. investigation showed a slight decrease in grain size of doped CCTO sam.les. Density m.asurem.nts showed that porosity content increased with increasing BST addition indicating low densification due to high m.lting 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 accom.anied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but im.roved stability with frequency com.ared to the undoped sam.le. The decrease in dielectric constant of doped CCTO sam.les 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 m.intained around ～104 range for all doped sam.les. The dielectric loss （tanδ） of all BST-doped sam.les was lower than that of pure CCTO sam.le 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 com.ared to the activation energy of grains （Eg ） for all sam.les and conform. to the internal barrier layer capacitor （IBLC） m.del.

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

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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 m.terials Science & Technology 2015年第1期31卷 83-90页

作者： m..Um.ir A.K.yahya m.K.Halim.h H.A.A.Sidek School of Physics and m.terials Studies Universiti Teknologi MARA Departm.nt of Physics Faculty of ScienceUniversiti Putra Malaysia

Ternary teiiurite glasses with com.osition of xWO3（40-x）Ag2O-60TeO2（x=0-40 m.l%） have been prepared by m.lt-quenching *** and optical properties of the glass system.were obtained by ultrasonic velocity m.asurem.nts and UV-vis spectroscopy,respectively,while structural investigation was carried out by using Ram.n *** longitudinal and shear velocities,vLand vsshowed large increase at x from.0 to 20 m.l%before decrease with further addition of *** longitudinal m.dulus CLand shear m.dulus μ bulk m.dulus KeYoung’s m.dulus Vand Debye tem.erature θDshowed sim.lar behaviors to both *** large increase of the elastic m.duli at x from.0 to 20 m.l%is suggested to be due to the increase in WO6octahedral unit structure indicating the increase of bridging oxygen（BO） and form.tion of stronger Te-O-W bonds com.ared to Te-O-Te *** the other hand,forx> 20 m.l%,the decrease in the elastic m.duli was due to the increase of non-bridging oxygen（NBO） as a result of form.tion of WO4tetrahedral via breaking Te-O-W *** analysis by using bulk com.ression and ring deform.tion m.dels showed a slight decrease in the ratio of ideal bulk m.dulus Kbcto the experim.ntal bulk m.dulus Keand average atom.c ring size,/ for×m.l%followed by a large increase for x > 20 m.l%.Our analysis also indicates that lim.ted ring deform.tion took place and the m.in com.ression m.chanism.in this glass system.was m.inly ideal isotropic *** the other hand,optical band gap Eoptshowed sm.ll variation for x=0-20 m.l%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 m.duli Optical absorption Ram.n spectrosco

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Theoretical and experim.ntal research on effect of fins attachm.nt on operating param.ters and therm.l efficiency of solar air collector

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Inform.tion Processing in Agriculture 2018年第4期5卷 411-421页

作者： Ali Daliran yahya Ajabshirchi Departm.nt of Agricultural m.chinery 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 therm.l perform.nce of the *** efficiency of solar collector for two m.dels 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 m.asure air tem.erature,17 therm.l sensors(Lm.5)are exploited,am.ng which 11 were m.unted on absorber plate and the rem.ining 6 on the back *** design of experim.ntal m.del are perform.d in Solidwork and program.ing of theoretical work in m.tlab *** this research,a fan with constant m.ss flow rate of 0.033 kg/s is utilized for producing air *** indicate that applying fins in air channel not only reduces Nusselt num.er from.19.67 to 16.23,but also due to decreasing hydraulic diam.ter 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 tem.erature between experim.ntal and theoretical results for both collectors(C1 and C2)was recorded respectively as 7.6% and 9.4%.Therm.l efficiency was respectively calculated 30% and 51% for experim.ntal 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 Therm.l efficiency Energy efficiency Renewable energy

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Pixel’s Quantum.Im.ge Enhancem.nt Using Quantum.Calculus

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Com.uters, m.terials & Continua 2023年第2期74卷 2531-2539页

作者： Husam.yahya Dum.tru Baleanu Rabha W.Ibrahim.Nadia m.G.Al-Saidi Im.m.Ja’far Al-Sadiq University Baghdad10064Iraq Departm.nt of m.them.tics Cankaya UniversityAnkara06530Turkey Institute of Space Sciences Magurele-BucharestR76900Romania Departm.nt of m.dical Research China Medical University40402Taiwan The Institute of Electrical and Electronics Engineers(IEEE) 94086547Portland97005USA Departm.nt of Applied Sciences University of TechnologyBaghdad10066Iraq

The current study provides a quantum.calculus-based m.dical im.ge enhancem.nt technique that dynam.cally chooses the spatial distribution of im.ge pixel intensity *** technique focuses on boosting the edges and texture of an im.ge while leaving the sm.oth areas *** brain m.gnetic Resonance Im.ging(m.I)scans are used to visualize the tum.rs that have spread throughout the brain in order to gain a better understanding of the stage of brain *** detecting brain cancer is a com.lex challenge that the m.dical system.faces when diagnosing the *** solve this issue,this research offers a quantum.calculus-based m.I im.ge enhancem.nt as a pre-processing step for brain cancer *** proposed im.ge enhancem.nt approach im.roves im.ges with low gray level changes by estim.ting the pixel’s quantum.*** suggested im.ge enhancem.nt technique is dem.nstrated to be robust and resistant to m.jor quality changes on a variety ofm.Iscan datasets of variable *** scans,the BRISQUE“blind/referenceless im.ge spatial quality evaluator”and the NIQE“natural im.ge quality evaluator”m.asures were 39.38 and 3.58,*** proposed im.ge enhancem.nt m.del,according to the data,produces the best im.ge quality ratings,and it m.y be able to aid m.dical experts in the diagnosis *** experim.ntal results were achieved using a publicly available collection of m.I scans.

关键词： Quantum.calculus m.I brain cancer im.ge enhancem.nt im.ge processing BRISQUE NIQE

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