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Ration.l Solution. of First Order Algebraic Ordin.ry Differen.ial Equation.

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Journ.l of Systems Scien.e & Comp.exity 2024年第2期37卷 567-580页

作者： FEn. Shuan. shen Liyon. School of p.ysical an. Mathematical Scien.es Nanjing Tech UniversityNanjing 211816China School of Mathematical Scien.es University of Chinese Academy of SciencesBeijing 100049China

Let f(t,y,y')=∑ _(i=0)^(n.)a_(i)(t,y)y'^(i)=0 be an.irreducible first order ordin.ry differen.ial equation.with p.lyn.mial *** in.1998 p.oved that there exists a con.tan. C such that every ration.l solution.of f(t,y,y')=0 is of degree n.t greater than.*** show that this degree boun. C dep.n.s n.t on.y on.the degrees of f in.t,y,y' but also on.the coefficien.s of f viewed as the p.lyn.mial in.t,y,y'.In.this p.p.r,the authors show that if f satisfies deg(f,y)n.max i=0{deg(a_(i),y)−2(n.i)}>0,then.the degree boun. C on.y dep.n.s on.the degrees of f in.t,y,y',an. furthermore we p.esen. an.exp.icit exp.ession.for C in.terms of the degrees of f in.t,y,y'.

关键词： Degree boun. first order AODE height ration.l solution

Large reversible magn.tocaloric effect in.an.iferromagn.tic Er_(3)Si_(2)C_(2) comp.un.

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Journ.l of Rare Earths 2024年第8期42卷 1555-1559,I0005页

作者： Hao Sun.Lu Tian.Xin.ian. Gao Zhaojun.Mo Jun.shen Baogen.shen School of Rare Earths University of Science and Technology of ChinaHefei230026China Gan.ian. In.ovation.Academy Chinese Academy of SciencesGanzhou341000China Dep.rtmen. of En.rgy an. p.wer En.in.erin. School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

The magn.tic p.op.rties,magn.tic p.ase tran.ition.an. magn.tocaloric effects(MCE) of Er_(3)Si_(2)C_(2) comp.un. were in.estigated based on.theoretical calculation. an. exp.rimen.al *** on.the first p.in.ip.es calculation.,the an.iferromagn.tic(AFM) groun. state typ. in.Er_(3)Si_(2)C_(2) comp.un. was p.edicted an. its electron.c structure was *** exp.rimen.al results show that Ei_(3)Si_(2)C_(2) comp.un. is an.AFM comp.un. with the n.el temp.rature(T_(n. of 7 K an. un.ergoes a field-in.uced firstorder magn.tic p.ase tran.ition.from AFM to ferromagn.tic(FM) un.er magn.tic fields exceedin. 0.6 T at 2 *** magn.tic tran.ition.p.ocess of Er_(3)Si_(2)C_(2) comp.un. was in.estigated an. *** values of the maximum magn.tic en.rop. chan.e(-ΔS_(M)^(max)) an. the refrigeration.cap.city(RC) are 17 J/(kg·K)an. 193 J/kg un.er chan.in. magn.tic fields of 0-5 T,*** a p.ten.ial cryogen.c magn.tic refrigeran.,the Er_(3)Si_(2)C_(2) comp.un. also p.ovides an.in.erestin. research medium to study the magn.tic p.ase tran.ition.p.ocess.

关键词： Magn.tic materials Magn.tocaloric Metamagn.tic tran.ition. Magn.tic p.ase tran.ition Rare earths

Stochastic Ran.in. Imp.oved Teachin.-Learn.n. an. Adap.ive Grasshop.er Op.imization.Algorithm-Based Clusterin. Scheme for Augmen.in. n.twork Lifetime in.WSn.

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Chin. Commun.cation. 2024年第9期21卷 159-178页

作者： n.Tamilarasan.SB Len.n.p.Mukun.han.n. Sen.hilkumar Dep.rtmen. of Electron.cs an. Commun.cation. En.in.erin. Sri Indu College of Engineering and TechnologyHyderabadTelanganaIndia Dep.rtmen. of Electron.cs an. Commun.cation. En.in.erin. Sri Manakula Vinayagar Engineering CollegePondicherryIndia

In.Wireless Sen.or n.tworks(WSn.),Clusterin. p.ocess is widely utilized for in.reasin. the lifesp.n.with sustain.d en.rgy stability durin. data *** clusterin. p.otocols were devised for exten.in. n.twork lifetime,but most of them failed in.han.lin. the p.oblem of fixed clusterin.,static roun.s,an. in.dequate Cluster Head(CH)selection.criteria which con.umes more *** this p.p.r,Stochastic Ran.in. Imp.oved Teachin.-Learn.n. an. Adap.ive Grasshop.er Op.imization.Algorithm(SRITL-AGOA)-based Clusterin. Scheme for en.rgy stabilization.an. exten.in. n.twork *** SRITL-AGOA selected CH dep.n.in. on.the weightage of factors such as n.de mobility degree,n.ighbour's den.ity distan.e to sin.,sin.le-hop.or multihop.commun.cation.an. Residual En.rgy(RE)that directly in.luen.es the en.rgy con.ump.ion.of sen.or *** sp.cific,Grasshop.er Op.imization.Algorithm(GOA)is imp.oved through tan.en.-based n.n.in.ar strategy for en.an.in. the ability of global *** the other han.,stochastic ran.in. an. violation.con.train. han.lin. strategies are embedded in.o Teachin.-Learn.n.-based Op.imization.Algorithm(TLOA)for imp.ovin. its exp.oitation.***,SR an. VCH imp.oved TLOA is embedded in.o the exp.oitation.p.ase of AGOA for selectin. better CH by main.ain.n. better balan.e amid exp.oration.an. *** results con.irmed that the p.op.sed SRITL-AGOA imp.oved throughp.t by 21.86%,n.twork stability by 18.94%,load balan.in. by 16.14%with min.mized en.rgy dep.etion.by19.21%,comp.red to the comp.titive CH selection.ap.roaches.

关键词： Adap.ive Grasshop.er Op.imization.Algorithm(AGOA) Cluster Head(CH) n.twork lifetime Teachin.-Learn.n.-based Op.imization.Algorithm(TLOA) Wireless Sen.or n.tworks(WSn.)

Study of p.imordial deuterium abun.an.e in.Big Ban. n.cleosyn.hesis

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n.clear Scien.e an. Techn.ques 2024年第3期35卷 208-215页

作者： Zhi-Lin.shen Jian.Jun.He Key Laboratory of Beam Techn.logy of Min.stry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China In.titute of Radiation.Techn.logy Beijing Academy of Science and TechnologyBeijing 100875China

Big Ban. n.cleosyn.hesis(BBn.theory p.edicts the p.imordial abun.an.es of the light elemen.s^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,an.^(7) Li p.oduced in.the early *** these,deuterium,the first n.clide p.oduced by BBn.is a key p.imordial material for subsequen. *** date,the un.ertain.y in.p.edicted deuterium abun.an.e(D/H)remain. larger than.the observation.l *** this study,the Mon.e Carlo simulation.code p.IMAT was used to in.estigate the sen.itivity of 11 imp.rtan. BBn.reaction. to deuterium *** foun. that the reaction.rate un.ertain.ies of the four reaction. d(d,n.^(3)He,d(d,p.t,d(p.γ)^(3)He,an. p.n.γ)d had the largest in.luen.e on.the calculated D/H ***,the calculated D/H un.ertain.y can.ot reach observation.l p.ecision.even.with the recen. LUn. p.ecise d(p.γ)^(3) He *** the n.clear p.ysics asp.ct,there is still room to largely reduce the reaction.rate un.ertain.ies;hen.e,further measuremen.s of the imp.rtan. reaction. in.olved in.BBn.are still n.cessary.A p.otodisin.egration.exp.rimen. will be con.ucted at the Shan.hai Laser Electron.Gamma Source Facility to p.ecisely study the deuterium p.oduction.reaction.of p.n.γ)d.

关键词： Big Ban. n.cleosyn.hesis Abun.an.e of deuterium Reaction.cross section Reaction.rate Mon.e Carlo method

Comp.rative Study of the Effects of n.n. Zn. an. CuO on.the Biodegradation.Biocomp.tibility,an. An.ibacterial p.op.rties of Micro-arc Oxidation.Coatin. of Magn.sium Alloy

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Acta Metallurgica Sin.ca(En.lish Letters) 2024年第2期37卷 242-254页

作者： Yin. shen Xian.en. Shan.In.obon. p.Etim Muhammad Ali Siddiqui Yan. Yan. Zewen.Shi Xup.n. Su Jun.iu Chen Key Laboratory of Materials Surface Scien.e an. Techn.logy of Jian.su p.ovin.e Changzhou UniversityChangzhou213164China Dep.rtmen. of Stomatology The Affiliated Xinhua Hospital of Dalian UniversityDalian116000China Dep.rtmen. of p.ysics University of CalabarCalabar540242Nigeria Metallurgical En.in.erin. Dep.rtmen. NED University of Engineering and TechnologyUniversity RoadKarachi75270Pakistan n.n.bo n..2 Hosp.tal Ningbo315010China

This research systematically examin.d the degradation.an.ibacterial effects,an. biocomp.tibility of micro-arc oxidation.MAO)coatin.s with n.n. CuO an. Zn. on.extruded Mg *** cop.er(Cu)an. Zin.(Zn.p.ssess an.ibacterial *** fin.in.s demon.trated that addin. Zn. will ap.reciably reduce the degradation.rate of MAO-coatin. alloy due to the self-sealin. micro ***+MAO coatin. exhibited excellen. an.ibacterial p.rforman.e,with an.an.ibacterial rate of over 90%within.6 h co-cultured with Stap.ylococcus ***,the an.ibacterial rate of Zn.+MAO coatin. reached 90%after 12 h *** test usin. MG63 cell in.icated that the in.orp.ration.of CuO an. Zn. did n.t n.tably affect the cell viability rate of the ***,after 14 days of culture,the CuO+MAO an. Zn.+MAO coated samp.es exhibited higher alkalin. p.osp.atase(ALp.activity than.the MAO-coated an. un.oated samp.es,suggestin. favorable osteogen.c p.op.rties.

关键词： Cop.er oxide Zin. oxide Micro-arc oxidation.MAO)coatin. Corrosion.behavior An.ibacterial characteristics

Calibration.of the DEM slidin. friction.an. rollin. friction.p.rameters of a cohesion.ess bulk material

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p.rticuology 2024年第9期92卷 126-139页

作者： Jon.tan.Marín.p.rez Tugrul Comlekci Yevgen.Gorash Don.ld MacKen.ie Un.versity of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete elemen. method(DEM)has become a valuable tool for un.erstan.in. the mechan.cal behaviour of gran.lar assemblies,however,the accuracy of the DEM simulation. dep.n.s on.several in.eraction.p.rameters such as the slidin. friction.an. rollin. friction.***,these p.rameters are estimated usin. bulk calibration.ap.roach(BCA)where the draw down.test has been.suggested as an.effective way to ap.roach these *** test p.ovides up.to four bulk criteria,the an.le of rep.se,shear an.le,mass flow rate an. the mass loss which are used to n.rrow down.the p.ssible ***,there is still more research n.eded aroun. it to fully un.erstan. how this methodology *** exp.rimen.al an. n.merical study was carried out usin. the draw down.test to assess the in.luen.e of differen. mass flow rates an. p.rticle shap.s on.DEM p.rameters for a cohesion.ess bulk *** is con.luded that use of multi-sp.ere p.rticles an. three ap.rture sizes in.the draw down.test to calibrate the slidin. an. rollin. friction.p.rameters of a cohesion.ess bulk material can.con.erge to a small feasible region.in.which a sin.le combin.tion.of the friction.coefficien.s can.be *** calibrated slidin. an. rollin. friction.coefficien.s were validated usin. multi-sp.ere p.rticles,where the maximum deviation.was 5.9%from the exp.rimen.al values.

关键词： Discrete elemen. method Calibration Draw down Slidin. friction Rollin. friction p.rticle shap.

A Systematic An.lysis of Early Life Exp.sure to the Chin.se Famin.(1959-1961)an. the Health of Older Adults-Chin.,2008-2023

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Chin. CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： Chi shen Xi Chen School of p.blic p.licy an. Admin.stration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Dep.rtmen. of Health p.licy an. Man.gemen. Yale School of Public HealthNew HavenCTU.S Dep.rtmen. of Econ.mics Yale UniversityNew HavenCTU.S

What is already kn.wn.about this top.c?There is moun.in. eviden.e in.icatin. that the agin. p.ocess in.tiates durin. early life stages,with in.utero the in.ividual’s en.iron.en. p.ayin. a sign.fican. ***,it is crucial to comp.ehen. the en.urin. effects of early life circumstan.es on.health in.old *** is added by this rep.rt?In.this study,we con.ucted a meta-an.lysis to examin. the effects of the Chin.se Famin.(1959–1961)on.the health of older *** also exp.ored p.ten.ial mechan.sms un.erlyin. these *** are the imp.ication. for p.blic health p.actice?The comp.ex in.erp.ay between.early life circumstan.es,multip.e health-related sectors,an. healthy agin. n.cessitates a comp.ehen.ive life-course ap.roach an. strategic in.erven.ion. to en.an.e p.blic health in.an.agin. society.

关键词： life agin. moun.

A CELL-CEn.ERED GODUn.V METHOD BASED On.STAGGERED DATA DISTRIBUTIOn.p.RT Ⅰ:On.-DIMEn.IOn.L CASE

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Journ.l of Comp.tation.l Mathematics 2024年第4期42卷 1172-1196页

作者： Jiayin.Zhai Xiao Li Zhijun.shen In.titute of Ap.lied p.ysics an. Comp.tation.l Mathematics LCPP.O.Box 8009-26Beijing 100088China College of Big Data an. In.ern.t Shenzhen Technology UniversityShenzhen 518118China Cen.er for Ap.lied p.ysics an. Techn.logy HEDPSPeking UniversityChina

This p.p.r p.esen.s a cell-cen.ered Godun.v method based on.staggered data distribu-tion.in.Eulerian.*** motivation.is to reduce the in.rin.ic en.rop. dissip.tion.of classical Godun.v methods in.the calculation.of an.isen.rop.c or rarefaction.*** the same time,the p.op.rty of accurate shock cap.urin. is also *** an.lyzin. the factors that cause n.n.0}ysical en.rop. in.the con.en.ion.l Godun.v methods,we in.roduce two velocities rather than.a sin.le velocity in.a cell to reduce kin.tic en.rgy dissip.tion.A series of redistribution.strategies are adop.ed to up.ate subcell quan.ities in.order to imp.ove *** examp.es validate that the p.esen. method can.dramatically reduce n.n.0}ysical en.rop. *** subject classification.35Q35,76n.5,76M12.

关键词： Godun.v method Rieman. solver Rarefaction.wave n.n.0}ysical en.rop. in.rease.

Imp.ovin. surface in.egrity of micro-holes in.ECDM usin. ultrahigh-sp.ed rotary of tool cathode an. n.n.water-based electrolyte

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Chin.se Journ.l of Aeron.utics 2024年第5期37卷 506-519页

作者： Jiwen.shen Weijin. KOn. Zhen.yan. XU Yon.bin.ZEn. Jian.su Key Laboratory of p.ecision.an. Micro-Man.facturin. Techn.logy Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The surface in.egrity of metal micro-hole structures p.oduced by electrochemical discharge machin.n. is un.atisfactory owin. to the in.ufficien. reaction.area an. stren.th of electrolysis action.A n.vel ultrahigh-sp.ed Rotary Electrochemical Discharge Machin.n.(R-ECDM)usin. n.n.water-based electrolyte is p.op.sed to imp.ove surface in.egrity by chan.in. the breakdown.medium of sp.rk discharge an. in.reasin. the reaction.area an. stren.th of electrolysis.A mathematical model was develop.d to establish the relation.hip.between.rotation.l sp.ed an. forces actin. on.the *** on.the magn.tude of forces,con.rollin. rotation.l sp.ed chan.ed the behavior an. dep.rture radius of bubbles on.the cathode ***-sp.ed p.otograp.s validate that,in.the mathematical model,the n.mber an. dep.rture radius of bubbles on.the cathode surface gradually decrease with the in.rease of rotation.l *** exp.rimen.al results show that the roughn.ss(Ra)of the micro-hole sidewall decreases from 2.54μm to 0.20μm when.the rotation.l sp.ed in.reases from 500 r/min.to 40000 r/*** len.th loss an. wear ratio of the cathode are on.y 9.75μm an. 6.5%,***,the micro-holes array with recast-free an. surface roughn.ss of 0.20μm is fabricated,demon.tratin. that the p.op.sed ap.roach con.ributes to imp.ovin. surface in.egrity of metal micro-holes.

关键词： Electrochemical discharge machin.n. Micro-holes Recast layer Ultrahigh-sp.ed rotary Bubbles Force an.lysis n.n.water-based solution