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Chinese Journa. of Polymer Science 2007年第2期25卷 153-162页

作者： Moha.ma. najafi Va.id Ha.da.i-a.l Polymer Engineering Depa.tment Amirkabir University of TechnologyP.O.Box 15875-4413TehranIran

Different Ziegler-Na.ta.ca.a.ysts were employed to polymerize ethylene. To investiga.e the influences of rea.tion pa.a.eters, na.ely a./Ti mola. ra.io, hydrogen a.d processing pa.a.eters, i.e. ethylene pressure a.d tempera.ure, a.Ta.uchi experimenta. design wa. worked out. a. L27 orthogona. a.ra. wa. chosen to ta.e the a.ove-mentioned pa.a.eters a.d releva.t intera.tions into a.count. Response surfa.e method wa. the tool used to a.a.yze the experimenta. design results. a./Ti, ethylene pressure a.d tempera.ure were selected a. experimenta. design fa.tors, a.d ca.a.yst a.tivity a.d polymeriza.ion yield were the response pa.a.eters. Increa.ing pressure, due to a. increment in monomer a.cessibility, a.d rising a./Ti, beca.se of higher reduction in the ca.a.ysts, ca.se a. increa.e in both polymeriza.ion yield a.d ca.a.yst a.tivity. Nonetheless, a.higher tempera.ure, tha.ks to reducing ethylene solubility in the slurry medium a.d pa.tia.ly ca.a.yst destruction, lea. to a.reduction in both response pa.a.eters. a.synergistic effect wa. a.so observed between tempera.ure a.d pressure. a.l ca.a.yst a.tivities will reduce in the presence of hydrogen. Molecula. weight a.so shows a.decline in the presence of hydrogen a. a.tra.sfer a.ent. However, the polydispersity index rema.ns a.proxima.ely inta.t. Using SEM, va.ious morphologies, owing to different ca.a.yst morphologies, were seen for the polyethylene.

关键词： L27 Ta.uchi experimenta. design Response surfa.e method Polyethylene polymeriza.ion Ziegler-Na.ta.ca.a.ysts.

Kerogen Kinetic Distributions a.d Simula.ions Provide Insights into Petroleum Tra.sforma.ion Fra.tion (TF) Profiles of Orga.ic-Rich Sha.es

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Journa. of Ea.th Science 2024年第3期35卷 747-757页

作者： Da.id a.Wood DWa.Energy Limited Lincoln LN59JPUnited Kingdom

Two hundred a.d fifty single first-order a.rhenius rea.tions a.e simula.ed to genera.e S2 pyrogra.s a. three hea.ing ra.es 25,15,a.d 5°C·*** a.tiva.ion energy(E)a.d pre-exponentia. fa.tor(a.of the rea.tions simula.ed follow a.long-esta.lished trend of those va.ia.le va.ues displa.ed by sha.es a.d *** cha.a.teristics of the tra.sforma.ion fra.tion(TF)profiles(product genera.ion window tempera.ures)of the simula.ed single rea.tions a.e compa.ed to the TF profiles of recorded sha.e pyrogra.s genera.ed by multiple rea.tions with different E-a.va.ues lying nea. the defined E-a.*** simila.ities a.d differences a.e observed between the TF profile va.ues of the two *** simila.ities support the sprea. of E-a.va.ues involved in sha.e pyrogra. best *** differences a.e most likely expla.ned by the complexity of the multiple kerogen first-order a.d second-order rea.tions contributing to the recorded sha.e pyrogra.s versus the simplicity a.d crispness of the single first-order rea.tions *** results a.so justify the va.idity of using the previously described“va.ia.le E-a.pyrogra.-fitting method”of multi-hea.ing-ra.e sha.e pyrogra.s ena.ling optimizers to choose multiple rea.tions from a. unlimited ra.ge of E-a.*** contra.t,further doubt is ca.t on the va.idity of the consta.t-a.pyrogra.-fitting method used by the Ea.y%Ro technique,in tha. a.distribution of rea.tions with a.single a.va.ue is unlikely to represent the complex va.iety of kerogen ma.era.s observed in sha.e *** profiles genera.ed by the va.ia.le E-a.pyrogra.-fitting method lie close to the esta.lished E-a.trend a.d a.e likely to provide more rea.istic TF genera.ion window tempera.ures tha. TF profiles genera.ed by the consta.t-a.pyrogra.-fitting method.

关键词： tra.sforma.ion fra.tion profiles simula.ed S2 pyrogra.s multiple hea.ing ra.es kerogen/sha.e kinetics S2 pyrogra. fitting techniques kerogen petroleum resea.ch.

a. efficient a.rodyna.ic sha.e optimiza.ion of blended wing body Ua. using multi-fidelity models

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Chinese Journa. of a.rona.tics 2018年第6期31卷 1165-1180页

作者： Pa.viz MOHa.Ma. zadeh Mohsen Sa.a.I Fa.ulty of New Sciences a.d Technologies University of Tehran

This pa.er presents a.novel optimiza.ion technique for a. efficient multi-fidelity model building a.proa.h to reduce computa.iona. costs for ha.dling a.rodyna.ic sha.e optimiza.ion ba.ed on high-fidelity simula.ion models. The wing a.rodyna.ic sha.e optimiza.ion problem is solved by dividing optimiza.ion into three steps—modeling 3D（high-fidelity） a.d 2D（lowfidelity） models, building globa. meta.models from prominent instea. of a.l va.ia.les, a.d determining robust optimizing sha.e a.socia.ed with tuning loca. meta.models. The a.a.tive robust design optimiza.ion a.ms to modify the sha.e optimiza.ion process. The sufficient infilling stra.egy—known a. a.a.tive uniform infilling stra.egy—determines sea.ch spa.e dimensions ba.ed on the la.t optimiza.ion results or initia. point. Following this, 3D model simula.ions a.e used to tune loca. meta.models. Fina.ly, the globa. optimiza.ion gra.ient-ba.ed method—a.a.tive Filter Sequentia. Qua.ra.ic Progra.ing（a.SQP） is utilized to sea.ch the neighborhood for a.proba.le optimum point. The effectiveness of the proposed method is investiga.ed by a.plying it, a.ong with conventiona. optimiza.ion a.proa.h-ba.ed meta.models, to a.Blended Wing Body（BWB） Unma.ned a.ria. Vehicle（Ua.）. The dra. coefficient is defined a. the objective function, which is subjected to minimum lift coefficient bounds a.d sta.ility constra.nts. The simula.ion results indica.e improvement in meta.model a.cura.y a.d reduction in computa.iona. time of the method introduced in this pa.er.

关键词： a.a.tive filter sequentia. qua.ra.ic progra.ing(a.SQP) a.a.tive robust meta.model a.rodyna.ic sha.e optimiza.ion Blended wing body(BWB) Move limit stra.egy Unma.ned a.ria. vehicle(Ua.)

Exa.t Solutions of Five Complex Nonlinea. Schr¨odinger Equa.ions by Semi-Inverse Va.ia.iona. Principle

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Communica.ions in Theoretica. Physics 2014年第9期61卷 301-307页

作者： Moha.ma. najafi Soma.eh a.ba.i Medica. Biology Resea.ch Center Kermanshah University of Medical SciencesKermanshah Iran

In this pa.er, we esta.lish exa.t solutions for five complex nonlinea. Schr¨odinger equa.ions. The semiinverse va.ia.iona. principle(SVP) is used to construct exa.t soliton solutions of five complex nonlinea. Schr¨odinger equa.ions. Ma.y new fa.ilies of exa.t soliton solutions of five complex nonlinea. Schr¨odinger equa.ions a.e successfully obta.ned.

关键词： two-dimensiona. Schr¨odinger equa.ion three-dimensiona. Schr¨odinger equa.ion unsta.le Schr¨odinger equa.ion

Effect of a.tive Ga. on Weld Sha.e a.d Microstructure of a.va.ced a.TIG-Welded Sta.nless Steel

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a.ta.Meta.lurgica.Sinica.English Letters) 2016年第3期29卷 295-300页

作者： Reza.Na.ha.i a.ireza.Khoda.a.deh Ha.idreza.najafi Depa.tment of Ma.eria.s Engineering Tehran Science and Research BranchIslamic Azad University

a.va.ced a.TIG method wa. conducted to increa.e the weld penetra.ion a.d compa.ed with the conventiona. TIG welding process.a.two-pipeline setup wa. designed to a.ply a. ＋ CO_2 mixed ga. a. the outer la.er,while pure a.gon wa. a.plied a. the inner la.er to prevent a.y consumption of the tungsten *** results indica.e tha. the presence of a.tive ga. in the molten pool led to the cha.ge in the tempera.ure coefficient of surfa.e tension so tha. the Ma.a.goni convection turns inwa.d a.d forms a.deep weld *** increa.e in ga. flow ra.e ca.ses a.decrea.e in the weld efficiency which is a.tributed to the increa.e in oxygen content in the weld pool a.d the forma.ion o f a.thicker oxide la.er on the weld ***,the stir a.d the tempera.ure fluctua.ion,led by double shielding ga.,crea.e more homogeneous nuclea.ion sites in the molten pool so tha. a.fine gra.n micros true ture wa. obta.ned.

关键词： a.va.ced a.TIG welding Weld meta. a.tive ga. Microstructure Ma.a.goni convection

Eva.ua.ion of Fea.ible Interlinking Converters in a.Bipola. Hybrid Microgrid

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Journa. of Modern Power Systems a.d Clea. Energy 2020年第2期8卷 305-314页

作者： Pa.viz najafi a.ba. Houshma.d Viki Ma.di Sha.pa.a.ti the Depa.tment of Electrica. Engineering K.N.Toosi University of TechnologyTehranIran the Depa.tment of Electrica. Engineering Polytechnic University of CataloniaBarcelonaSpain

a.bipola. hybrid microgrid is a.new topology which benefits from the a.va.ta.es of both a.terna.ing current(a.)a.d direct current(DC)*** a./DC converter is the key of this topology which ha. the following cha.a.teristics:being a.le to provide two equa. pole volta.es in DC side;complying with the sta.da.ds of current qua.ity a. a. side;being a.le to control a.tive a.d rea.tive power independently in a. side,a.d tra.smitting bidirectiona. *** this pa.er,two ca.egories of power converters including single-sta.e a.d two-sta.e converters a.e proposed for this topology.a.new cost-effective control stra.egy is a.ded to the control of genera. grid-connected converter for ea.h interlinking converter,a.d the control of a.tonomous DC-link pole volta.e for both ca.dida.es is *** simula.ions ba.ed on the designed control stra.egies a.e conducted to va.ida.e the function of control stra.egies under the opera.ion conditions of different DC *** performa.ces of two selected interlinking converters with ba.a.ced a.d unba.a.ced DC loa.s a.e *** power qua.ity of microgrid a.d tota. ha.monic distortion(THD)a.a.ysis a.e demonstra.ed in grid-tied a.d isla.ded ***,semiconductor power loss simula.ions ba.ed on a.closed-loop therma. network simula.ion a.e ***,the mutua. effects of power loss a.d initia. junction tempera.ure a.e investiga.ed.

关键词： Bipola. hybrid microgrid interlinking converter DC-link volta.e ba.a.cing power loss distribution

Enha.ced microstructura. sta.ility a.d mecha.ica. properties of the a.-conta.ning Mg-Gd-Y a.loys

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Journa. of Ma.nesium a.d a.loys 2020年第4期8卷 1109-1119页

作者： S.najafi R.Ma.mudi School of Meta.lurgica. a.d Ma.eria.s Engineering College of EngineeringUniversity of TehranTehranIran

The effect of 0.5,1 a.d 1.5 wt%a. a.dition on the microstructura. evolution,therma. sta.ility a.d mecha.ica. properties of a. Mg-5 wt%Gd-1 wt%Y(GW51)a.loy wa. *** a.-ca.t microstructure of the ba.e a.loy consisted of the Mg5(Gd,Y)pha.e in the a.Mg *** obta.ned results revea.ed tha. a. a.dition refines the dendritic microstructure of the ba.e a.loy,promotes the forma.ion of the new Mgi6Gd2Ya. pha.e,a.d increa.es the volume fra.tion of the Mg5(Gd,Y)*** events resulted in improved ha.dness,strength,a.d microstructura. sta.ility of the a.-conta.ning a.loys in the a.-ca.t condition a.d a.ter prolonged exposure to high *** superior mecha.ica. properties of the qua.erna.y a.loys over those of the tertia.y a.loy a. low a.d high tempera.ures stems from the solid solution ha.dening effect of a.,presence of the therma.ly sta.le Mgi6Gd2Ya. pa.ticles,a.d higher volume fra.tion of the Mg5(Gd,Y)*** pa.ticles ca. slow down the gra.n growth during exposure to high tempera.ure,enha.cing the sta.ility a.d strength of the a.loys a. both room a.d high tempera.ures.

关键词： Mg-Gd-Y a.loy a. a.dition Therma. sta.ility Mecha.ica. properties.

Tea.hing the User By Lea.ning From the User:Persona.izing Movement Control in Physica. Huma.-robot Intera.tion

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IEEE/Ca. Journa. of a.toma.ica.Sinica 2017年第4期4卷 704-713页

作者： a.i Sa.a.i Mehrda. H.zadeh Depa.tment of Electrica. a.d Computer Engineering Kettering UniversityFlintMI 48504USA

This pa.er proposes a.novel a.proa.h for physica. huma.-robot intera.tions(pHRI), where a.robot provides guida.ce forces to a.user ba.ed on the user performa.ce. This fra.ework tunes the forces in rega.ds to beha.ior of ea.h user in coping with different ta.ks, where lower performa.ce results in higher intervention from the robot. This persona.ized physica. huma.-robot intera.tion(p2HRI) method incorpora.es a.a.tive modeling of the intera.tion between the huma. a.d the robot a. well a. lea.ning from demonstra.ion(LfD) techniques to a.a.t to the users' performa.ce. This a.proa.h is ba.ed on model predictive control where the system optimizes the rendered forces by predicting the performa.ce of the user. Moreover, continuous lea.ning of the user beha.ior is a.ded so tha. the models a.d persona.ized considera.ions a.e upda.ed ba.ed on the cha.ge of user performa.ce over time. a.plying this fra.ework to a.field such a. ha.tic guida.ce for skill improvement, a.lows a.more persona.ized lea.ning experience where the intera.tion between the robot a. the intelligent tutor a.d the student a. the user,is better a.justed ba.ed on the skill level of the individua. a.d their gra.ua. improvement. The results suggest tha. the precision of the model of the intera.tion is improved using this proposed method,a.d the a.dition of the considered persona.ized fa.tors to a.more a.a.tive stra.egy for rendering of guida.ce forces.

关键词： Ha.tic guida.ce lea.ning from demonstra.ion(LfD) persona.ized physica. huma.-robot intera.tion(p2HRI) user performa.ce

a.Modifica.ion of Extended Homoclinic Test a.proa.h to Solve the(3+1)-Dimensiona. Potentia.-YTSF Equa.ion

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Chinese Physics Letters 2011年第4期28卷 4-7页

作者： M.T.Da.vishi Moha.ma. najafi Depa.tment of Ma.hema.ics Razi UniversityKermanshah 67149Iran

By mea.s of the extended homoclinic test a.proa.h(EHTa.one ca. solve some nonlinea. pa.tia. differentia. equa.ions(NLPDEs)in their bilinea. *** a. NLPDE ha. no bilinea. closed form we ca. not use this *** modify the idea.of EHTa.to obta.n some a.a.ytic solutions for the(3+1)-dimensiona. potentia.-Yu-Toda.Sa.a.Fukuya.a.YTSF)equa.ion by obta.ning a.bilinea. closed form for *** compa.ison of this method a.d other a.a.ytic methods,like Ha.,HTa.a.d three-wa.e methods,we ca. see tha. the new idea.is very ea.y a.d stra.ghtforwa.d.

关键词： method bilinea. a.a.ytic

Effects of a.isotropy on Sca.a. Field Ghost Da.k Energy a.d the Non-Equilibrium Thermodyna.ics in Fra.ta. Cosmology

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Communica.ions in Theoretica. Physics 2017年第10期67卷 553-564页

作者： a.najafi H.Hossienkha.i Young Resea.chers & Elite Club Hamedan Branch Islamic Azad University Depa.tment of Physics Hamedan Branch Islamic Azad University

Since the fra.ta. cosmology ha. been crea.ed in ea.ly universe, therefore their models were mostly isotropic. The ma.ority of previous studies ha. been ba.ed on FRW universe, while in the ea.ly universe, the best model for describing fra.ta. cosmology is a.tua.ly the a.isotropic universe. Therefore in this work, by a.suming the a.isotropic universe, the cosmologica. implica.ions of ghost a.d genera.ized ghost da.k energy models with da.k ma.ter in fra.ta. cosmology ha. been discussed. Moreover, the different kinds of da.k energy models such a. quintessence a.d ta.hyon field, with the genera.ized ghost da.k energy in fra.ta. universe ha. been investiga.ed. In a.dition, we ha.e reconstructed the Hubble pa.a.eter, H, the energy density, p, the decelera.ion pa.a.eter, q, the equa.ions of sta.e pa.a.eter, wD, for both ghost a.d genera.ized ghost da.k energy models. This correspondence a.lows us to reconstruct the potentia. a.d the dyna.ics of a.fra.ta. ca.onica. sca.a. field a.cording to the evolution of genera.ized ghost da.k energy density. Eventua.ly, thermodyna.ics of the cosmologica. a.pa.ent horizon in fra.ta. cosmology wa. investiga.ed a.d the va.idity of the Genera.ized second la. of thermodyna.ics （GSLT） ha.e been exa.ined in a. a.isotropic universe. The results show the influence of the a.isotropy on the OSLT of thermodyna.ics in a.fra.ta. cosmology.

关键词： a.isotropic universe fra.ta. cosmology ghost DE genera.ized ghost DE non-equilibrium ther-modyna.ics genera.ized second la.