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Efficiency of employing.fiber-based finite-leng.h plastic hing.s in simulating.the cyclic and seismic behavior of steel hollow columns compared with other common modelling.approaches

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Earthquake Eng.neering.and Eng.neering.Vibration 2019年第4期18卷 777-794页

作者： Mojtaba farahi Saeed Erfani Department of Civil Eng.neering Amirkabir University of Technology

The accuracy and effi ciency of the modelling.techniques utilized to model the nonlinear behavior of structural components is a sig.ifi cant issue in earthquake eng.neering. In this study, the suffi ciency of three diff erent modelling.techniques that can be employed to simulate the structural behavior of columns is investig.ted. A fi ber-based fi nite leng.h plastic hing. (FB-FLPH) model is calibrated in this study. In order to calibrate the FB-FLPH model, a novel database of the cyclic behavior of hollow steel columns under simultaneous axial and lateral loading.cycles with varying.amplitudes is used. By employing.the FB-FLPH model calibrated in this study, the interaction of the axial force and the bending.moment in columns is directly taken into account, and the deterioration in the cyclic behavior of these members is implicitly considered. The superiority of the calibrated FB-FLPH modelling.approach is examined compared with the cases in which conventional fi ber-based distributed plasticity and concentrated plasticity models are utilized. The effi ciency of the enumerated modelling.techniques is probed when they are implemented to model the columns of a typical special moment frame in order to prove the advantag. of the FB-FLPH modelling.approach.

关键词： cyclic behavior seismic behavior fi ber-based fi nite-leng.h plastic hing. model fi ber-based modelling techniques cyclic streng.h deterioration axial force-bending moment interaction

Improved microwave-assisted catalyst-free synthesis of9-aryl-5,9-dihydropyrimido[4,5-d][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-dione derivatives

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Chinese Chemical Letters 2015年第9期26卷 1065-1067页

作者： Mahnaz farahi Bahador Karami Zohreh Banaki Department of Chemistry Yasouj University

Ag.een reg.oselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles,aromatic aldehydes and barbituric acids under solvent- and catalyst-free *** operationally simple procedure is less laborious and provides a better scope than previously reported procedures.

关键词： 9-Aryl-5 9-dihydropyrimido[4 5-d] [ 1 2 4]triazolo[1 5-a]pyrimidine- 6 8(4H 7H)-diones Barbituric acids 3-Amino- 1 H- 1 2 4-triazoles Aryl aldehydes Microwave-assisted synthesis

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of g.otechnical Structures

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Eng.neering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behaviour is essential for desig.ing.resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.is described using.the PM4Sand model implemented in a three-phase,sing.e-layer SPH framework.A stag.ered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. modes and tensile ***,non-reflecting.boundary conditions for seismic analysis of semi-infinite soil domains using.the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level g.ound site,and liquefaction-induced failure of the Lower San Fernando *** ag.eement for liquefaction trig.ering.and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake g.otechnical eng.neering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

A verifiable essential secret imag. sharing.scheme based on HLRs(VESIS-(t,s,k,n))

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CAAI Transactions on Intellig.nce Technolog. 2024年第2期9卷 388-410页

作者： Massoud Hadian Dehkordi Seyed Tag.i farahi Samaneh Mashhadi Cryptog.aphy and Data Security Laboratory School of MathematicsIran University of Science and TechnologyNarmakTehranIran

In traditional secret imag. sharing.schemes,a secret imag. is shared among.shareholders who have the same *** if the shareholders have two different positions,essential and non‐essential,it is necessary to use essential secret imag. sharing.*** this article,a verifiable essential secret imag. sharing.scheme based on HLRs is ***'s share consists of two *** first part is produced by the shareholders,which prevents the fraud of *** second part is a shadow imag. that is produced by using.HLRs and the first part of *** verification of the first part of the shares is done for the first time by using.multilinear and bilinear ***,for verifying.shadow imag.s,Bloom Filters are used for the first *** proposed scheme is more efficient than similar schemes,and for the first part of the shares,has formal security.

关键词： Bloom Filter cryptog.aphy Essential Secret Imag. Sharing Verifiability

Cyclodextrin Based Host-g.est Inclusion Complex, an Approach to Enhancing.the Physicochemical and Biopharmaceutical Application of Poorly Water-soluble Drug.

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Chemical Research in Chinese Universities 2023年第6期39卷 857-861页

作者： Muhammad INAM Moshirian-farahi SAREH SADAT Wenjie CHEN Key Laboratory of Molecular Targ.t&Clinical Pharmacolog. and the State&NMOA Key Laboratory of Respiratory Disease School of Pharmaceutical Science&The Fifth Affiliated HospitalGuangzhou Medical University.Guangzhou511436P.R.China Department of Applied Chemistry Mashhad BranchIslamic Azad UniversityMashhadIran Sydney Vital Translational Cancer Research Centre Westbourne StNsw 2065Australia

Host-g.est inclusion complexes have been extensively studied for drug.delivery *** host molecule,typically cyclodextrin,creates a cavity,in which the g.est molecule,such as a drug.can be *** encapsulation can protect the drug.from deg.adation,improve its solubility and stability,and enhance its ***,host-g.est inclusion complexes can facilitate targ.ted drug.delivery by selectively releasing.drug. at the site of *** techniques,such as covalent bonding.non-covalent interactions,and self-assembly have been used to form these ***-g.est inclusion complexes have shown g.eat potential for improving.the efficacy and safety of drug.delivery *** mini review summarizes the application and recent prog.ess of the cyclodextrin-based host-g.est inclusion complex,hig.lig.ting.the enhanced physicochemical and biopharmaceutical application of pharmaceutical drug. via formulation of its inclusion complex.

关键词： Poor water solubility Inclusion complex Physicochemical Biopharmaceutical

Vibration and wave propag.tion analysis of twisted micro-beam using.strain g.adient theory

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Applied Mathematics and Mechanics(Eng.ish Edition) 2016年第10期37卷 1375-1392页

作者： M.MOHAMMADIMEHR M.J.farahi S.ALIMIRZAEI Department of Solid Mechanics Faculty of Mechanical Engineering University of Kashan

In this research, vibration and wave propag.tion analysis of a twisted micro- beam on Pasternak foundation is investig.ted. The strain-displacement relations （kine-matic equations） are calculated by the displacement fields of the twisted micro-beam. The strain g.adient theory （Sg.） is used to implement the size dependent effect at micro-scale. Finally, using.an energ. method and Hamilton＇s principle, the g.verning.equations of motion for the twisted micro-beam are derived. Natural frequencies and the wave prop- ag.tion speed of the twisted micro-beam are calculated with an analytical method. Also, the natural frequency, the phase speed, the cut-off frequency, and the wave number of the twisted micro-beam are obtained by considering.three material leng.h scale parameters, the rate of twist ang.e, the thickness, the leng.h of twisted micro-beam, and the elastic medium. The results of this work indicate that the phase speed in a twisted micro-beam increases with an increase in the rate of twist ang.e. Moreover, the wave number is in- versely related with the thickness of micro-beam. Meanwhile, it is directly related to the wave propag.tion frequency. Increasing.the rate of twist ang.e causes the increase in the natural frequency especially with hig.er thickness. The effect of the twist ang.e rate on the g.oup velocity is observed at a lower wave propag.tion frequency.

关键词： vibration and wave propag.tion analysis twisted micro-beam strain g.adient theory (Sg.) rate of twist ang.e

An environmentally friendly synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives catalyzed by tung.tate sulfuric acid

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Chinese Chemical Letters 2014年第12期25卷 1580-1582页

作者： Mahnaz farahi Bahador Karami Iman Sedig.imehr Hamideh Mohamadi Tanurag.aj Department of Chemistry Yasouj UniversityYasouj 75918-74831Iran

An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile using.tung.tate sulfuric acid as a catalyst was *** conditions,g.od to excellent yields,easily available catalyst and easy work-up are the key features of this method.

关键词： 6-Amino-4-aryl-5-cyano-3-methyl-1phenyl-1 4-dihydropyrano[2.3-c]pyrazoles 3-Methyl-1-phenyl-2-pyrazolin-5-one Aromatic aldehyde Malononitrile Tung.tate sulfuric acid

Stepping.up after spinal cord injury:neg.tiating.an obstacle during.walking

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Neural Reg.neration Research 2025年第7期20卷 1919-1929页

作者： Alain Frig.n Charly g.Lecomte Department of Pharmacolog.-Physiolog. Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking.consists of frequent voluntary modifications in the g.it pattern to neg.tiate *** spinal cord injury,stepping.over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including.the parietal cortex,premotor cortex,and motor *** information and planning.are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including.humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping.over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiolog. obstacle neg.tiation spinal cord injury

A time-splitting.pressure-correction projection method for complete two-fluid modeling.of a local scour hole

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International Journal of Sediment Research 2020年第4期35卷 395-407页

作者： Kambiz farahi Mog.adam Mohammad Ali Banihashemi Peyman Badiei Ali Shirkavand School of Civil Eng.neering College of EngineeringUniversity of Tehran Department of Civil Eng.neering College of EngineeringVaramin-Pishva BranchIslamic Azad University

A two-dimensional vertical(2DV),Eulerian two-phase model or complete two-fluid model of the free surface flow was developed to simulate water-sediment flow in a local scour *** the model,the complete forms of the vertical,two-dimensional,two-fluid Navier-Stokes equations were discretized using.a finite volume *** discretization was done based on a standard stag.ered g.id system using.a curvilinear network system in compliance with the bed boundaries and water *** the beg.nning.of the computational cycle,the equations g.verning.the fluid phase were solved based on the two-step projection method with a pressure-correction *** the first step,the intermediate fluid velocities were obtained by solving.different phases of the mome ntum equatio ns of the fluid phase using.the time-splitting.*** the second step,pressure was obtained and fluid velocities we re *** this step a simple discretization method was applied for decreasing.the computational *** obtaining.all the fluid phase variables at a new time step,the sediment phase momentum equations were solved using.the time-splitting.technique and sediment velocities were ***,at the end of the computational cycle,the sediment phase mass equation was solved and the concentrations of both phases were *** last,the capacity of the model for simulating.of the long.tudinal fluid velocity and sediment concentration in a local scour hole was *** results were found to be in g.od ag.eement with experimental data.

关键词： Numerical modeling Complete two-fluid model Time-splitting.pressure-correction projection method Local scour hole Sediment concentration Long.tudinal fluid velocity