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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

Toward a comprehensive hypothesis of oxygen-evolution reaction in the presence of iron and gold

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Journal of Energy Chemistry 2024年第2期89卷 172-183,I0005页

作者： Negah Hashemi jafar Hussain Shah Cejun Hu Subhajit Nandy Pavlo Aleshkevych Sumbal Farid Keun Hwa Chae Wei Xie Taifeng Liu Junhu Wang Mohammad Mahdi Najafpour Department of Chemistry Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Center for Advanced Mössbauer Spectroscopy Mössbauer Effect Data CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Lab of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China Advanced Analysis Center Korea Institute of Science and TechnologySeoul 02792Republic of Korea Institute of Physics Polish Academy of SciencesWarsaw 02-668Poland National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina Center of Climate Change and Global Warming Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research Center for Basic Sciences&Modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran

This study investigates the effects of Fe on the oxygen-evolution reaction(OER)in the presence of *** distinct areas of OER were identified:the first associated with Fe sites at low overpotential(~330 mV),and the second with Au sites at high overpotential(~870 mV).Various factors such as surface Fe concentration,electrochemical method,scan rate,potential range,concentration,method of adding K_(2)Fe O_(4),nature of Fe,and temperature were varied to observe diverse behaviors during OER for Fe O_(x)H_(y)/*** amounts of Fe ions had a significant impact on OER,reaching a saturation point where the activity did not increase *** electronic interaction between Fe and Au ions was indicated by X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)*** situ visible spectroscopy confirmed the formation of Fe O_(4)^(2-)during *** situ Mossbauer and surfaceenhanced Raman spectroscopy(SERS)analyses suggest the involvement of Fe-based species as intermediates during the rate-determining step of OER.A lattice OER mechanism based on Fe O_(x)H_(y)was proposed for operation at low *** functional theory(DFT)calculations revealed that Fe oxide,Fe-oxide clusters,and Fe doping on the Au foil exhibited different activities and stabilities during *** study provides insights into the interplay between Fe and Au in OER,advancing the understanding of OER mechanisms and offering implications for the design of efficient electrocatalytic systems.

关键词： DFT calculation Fe/Au electrocatalysis Mechanism Oxygen evolution Water oxidation

The Combination Effect of Daphne Extract and Imatinib on the Antiproliferative Activity of the K562 Cell Line

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Journal of Biosciences and Medicines 2024年第8期12卷 141-153页

作者： Alireza Khorshid jafar Nouri Nojadeh Javid Sabour Takanlu Alireza Tavasoli Department of Clinical Laboratory Sciences University of Texas Medical Branch at Galveston Galveston TX USA Department of Medical Genetics Faculty of Medicine Tabriz University of Medical Sciences Tabriz Iran Apoptosis Research Centre Department of Biochemistry School of Natural Sciences National University of Ireland Galway Galway Ireland Department of Pathology School of Medicine Fasa University of Medical Science Fasa Iran

Background: Herbal medicine is well-known among the ancient medical sciences. Healing properties have been observed in some species of Daphne plant. The effect of Daphne plant extract on the K562 cell line has been previously studied, and Gleevec is a well-known and effective medicine for the treatment of chronic myelogenous leukemia. Material and Methods: In this study, the simultaneous effects of using herbal medicine and a target therapy medicine on the K562 cell line were investigated. The presence of some species of Daphne in Iran motivated us to evaluate the cytotoxic effect of Daphne mucronata on human leukemia cancer cells. The antiproliferative activity of the dichloromethane extract of Daphne mucronate (Thymelaeaceae), a new anticancer medicinal plant, was evaluated. Cell viability was quantitated by MTT assay. Apoptotic and necrotic changes in the cell membrane were examined using flow cytometry. Changes in Bax and Bcl2 gene expression were investigated using real-time PCR. The MIC and the IC50 of the crude extract were calculated, and the MIC and IC50 of the Daphne extract in combination of imatinib were tested in the K-562 cell line. Results: K-562 cells responded to the extract treatments in a dose-dependent manner, and the increase in the expression of Bcl2 and decrease in the expression of the Bax gene intensified with increasing extract concentration. Flow cytometry revealed that most of the cells underwent necrosis. Conclusion: Daphne extract effectively decreased the viability of the K562 cell line. The necrotic effect of the Daphne extract was evaluated, and an increase in the gene expression of Bcl2 was observed in cells exposed to the Daphne extract. The combination of Daphne extracts with imatinib enhances the cytotoxic effect of imatinib.

关键词： Daphne Imatinib Apoptosis Herbal Medicine Bax Bcl-2 CML

Forced vibration of smart laminated viscoelastic plates by RPT finite element approach

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Acta Mechanica Sinica 2020年第4期36卷 933-949页

作者： jafar Rouzegar Maryam Davoudi Department of Mechanical and Aerospace Engineering Shiraz University of TechnologyShirazIran

In this study,a finite element formulation based on the four-variable refined plate theory(RPT)is presented for forced vibration analysis of laminated viscoelastic composite plates integrated with a piezoelectric *** the best of the authors’knowledge,this is the first time that the proposed approach is extended for study of the dynamic behavior of the smart viscoelastic *** utilized RPT which works for both thick and thin plates predicts a parabolic variation for transverse shear stresses across the plate *** a linear viscoelastic model for the substrate material,the relaxation module is predicted by the Prony *** Hamilton’s principle,the weak form equation is constructed and a four-node rectangular plate element is utilized for discretizing the *** Newmark scheme is employed for advancing the solution in time.A MATLAB code is developed based on the formulations and several benchmark problems are *** the findings with existing results in previous studies confirms the accuracy and efficiency of the proposed *** dynamic response of the smart viscoelastic plates under various electromechanical loads is investigated and the results show that *** can be passively controlled by adding and actuating the piezoelectric *** damping effects of viscoelastic parameters on the results are investigated,too.

关键词： Forced vibration Refined plate theory Viscoelastic material Piezoelectricity Smart structure Finite element method

MULTI-CRITERIA UNIVERSITY SELECTION:FORMULATION AND IMPLEMENTATION USING A FUZZY AHP

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Journal of Systems Science and Systems Engineering 2015年第3期24卷 293-315页

作者： Negin Salimi jafar Rezaei Faculty of Technology Policy and ManagementDelft University of Technology

Collaboration with universities as ＇knowledge factories＇ is increasingly perceived to be an effective and viable solution for firms to gain competitive advantage. One of the main challenges firms face in this area is how to select the best university for collaboration. This selection undoubtedly affects some other strategic activities of firms, such as managing and governing the relationship with the selected university and, most importantly, firm performance. As such, the selection becomes an important strategic decision that deserves a great deal of attention. Thus far, no systematic attempt has been made to investigate this significant area of research. The main purpose of this study is to formulate a decision-making model for university selection. Reviewing existing literature of university-industry relationship yields a list of relevant criteria for this problem. The problem is then formulated as a multi-criteria decision-making （MCDM） model, and a fuzzy AHP is used to provide the solution. To illustrate the model, three Dutch universities are ranked based on the importance of the selected criteria.

关键词： University-industry relationship university selection multi-criteria decision-making(MCDM) analytic hierarchy process (AHP) fuzzy analytic hierarchy process (FAHP)

Zero-Bias Conductance versus Potential Strength of Interface in Ferromagnetic Superconductors

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Chinese Physics Letters 2012年第3期29卷 201-203页

作者： Hamidreza Emamipour jafar Emamipour Department of Physics Ilam UniversityIlamIran Young Researchers Club Ilam BranchIslamic Azad UniversityIlamIran

We study zero-bias conductance(ZBC)spectra of a normal-metal/insulator/singlet(and triplet)ferromagnetic superconductor as a function of potential strength of interface in the Blonder-Tinkham Klapwijk(BTK)theory *** consider possible pairing states including spin singlet s-wave pairing(SWP),spin triplet opposite spin pairing(OSP)and spin triplet equal spin pairing(ESP).It is found that ZBC as a function of potential strength of interface shows a clear difference between SWP,OSP and ESP *** results may serve as a useful tool for discriminating pairing states in ferromagnetic superconductors.

关键词： ferromagnetic singlet interface

Spherical Kadomtsev-Petviashvili Solitons in a Suprathermal Complex Plasma

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Communications in Theoretical Physics 2013年第8期60卷 227-232页

作者： Mehran Shahmansouri jafar Borhanian Department of Physics Faculty of ScienceArak UniversityArakP.O.Box 38156-8-8349Iran Department of Physics Faculty of ScienceUniversity of Mohaghegh ArdabiliP.O.Box 179ArdabilIran

The nonlinear aspects of nonplanar dust acoustic (DA) solitary waves are investigated in an unmagnetized complex plasma comprising of cold dust grains,kappa-distributed ions as well as *** nonplanar DA solitons are studied based on the reductive perturbation *** is shown that the evolution of DA solitons is governed by a spherical Kadomtsev-Petviashvili (sKP) equation and then the impact of suprathermality on the spatial structure as well as the nature of DA soliton is *** seems that the properties of DA solitons in nonplanar geometry are quite different from that of the planar solitons.

关键词： dust-acoustic solitons superthermal ion/electron nonplanar waves

TWO-VARIABLE JACOBI POLYNOMIALS FOR SOLVING SOME FR ACTIONAL PA RTIAL DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2020年第6期38卷 879-902页

作者： jafar Biazar Khadijeh Sadri Department of Applied Mathematics Faculty of Mathematical SciencesUniversity of GuilanP.O.Box 41335-1914GuilanRashtIran

Tw o variable Jacobi polynomials,as a two-dimensional basis,are applied to solve a class of temporal fractional partial differential *** fractional derivative operators are in the Caputo *** operational matrices of the integration of integer and fractional orders are *** these matrices together with the Tau Jacobi method converts the main problem into the corresponding system of algebraic *** error bound is obtained in a two-dimensional Jacobi-weighted Sobolev ***,the efficiency of the proposed method is demonstrated by implementing the algorithm to several illustrative *** will be compared witli those obtained from some existing methods.

关键词： Fractional partial differential equation Two-variable Jacobi polynomials Caputo derivative Error bound.

Fischer–Tropsch synthesis using Co and Co-Ru bifunctional nanocatalyst supported on carbon nanotube prepared via chemical reduction method

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Journal of Energy Chemistry 2019年第1期28卷 9-22页

作者： jafar Shariati Ali Haghtalab Amir Mosayebi Department of Chemical Engineering Tarbiat Modares University Department of Chemical Engineering Tafresh University

We used a chemical reduction method to synthesize the catalysts of cobalt(Co) and cobalt-ruthenium(Co-Ru) bifunctional supported on carbon nanotubes(CNTs) for Fischer–Tropsch synthesis(FTS) in a fixedbed reactor. These Co-Ru/CNTs catalysts were synthesized with various weight proportions of Ru/Co(0.1 to 0.4 wt%) with keeping a fixed amount of cobalt(10 wt%). Moreover, for comparison purpose, CNTs supported Co-and Co(Ru)-based catalysts at same loading as the above catalysts were prepared through impregnation method. We characterize the present catalysts through the various techniques such as Energy–dispersive X-ray(EDX), Transmission Electron Microscopy(TEM), Brunauer–Emmett–Teller(BET),Hydrogen-Temperature-Programmed Reduction(H_2-TPR), Hydrogen-Temperature-Programmed Desorption(H_2-TPD) and O_2 titration. Thus using the chemical reduction method, a narrow particle size distribution was obtained so that the small cobalt particles were confined inside the CNTs. The Co-based catalyst prepared by impregnation was compared with the Co-Ru catalysts at the same loading. The results demonstrated that the use of chemical reduction method led to decrease the average Co oxide cluster size to8.7 nm so that the reduction enhanced about 24% and stabilized an earlier time at the stream. Among the prepared catalysts, the results indicated that the Co-Ru/CNTs catalysts demonstrated high catalytic activity with the highest long-chain hydrocarbons(C_(5+)), selectivity up to 74.76%, which was higher than those we obtained by the Co-Ru/γ-Al_2O_3(61._20%), Co/CNTs(43.68%) and Co/γ-Al_2O_3(37.69%). At the same time, comparing with those catalyst synthesized by impregnation, the use of chemical reduction led to enhancement of the C_(5+) selectivity from 59.30% to 68.83% and increment in FTS rate about 11% for the Co-Ru/CNTs catalyst.

关键词： Cobalt-ruthenium Carbon nanotubes Fischer-Tropsch synthesis Catalyst nanoparticles Chemical reduction method