简介:Thispaperconsiderstheasymptoticstabilityanalysisofbothexactandnumericalsolutionsofthefollowingneutraldelaydifferentialequationwithpantographdelay.{x′(t)+Bxd(t)+Cx′(qt)+Dx(qt)=0,t>0,x(0)=X0,}whereB,C,D∈C^d×d,q∈(0,1),andBisregular.Aftertransformingtheaboveequationtonon-automaticneutralequationwithconstantdelay,wedeterminesufficientconditionsfortheasymptoticstabilityofthezerosolution.Furthermore,wefocusontheasymptoticstabilitybehaviorofRunge-Kuttamethodwithvariablestepsize.ItisprovedthataLstableRunge-Kuttamethodcanpreservetheabove-mentionedstabilityproperties.
简介:穿孔等离子弧焊接过程中,小孔的形状和尺寸决定着热源热流密度的分布和温度场的分布,从而影响着焊接过程的稳定性和焊接质量。本文利用四阶Runge-Kutta法求解在小孔壁上的力的控制方程组。数据表明模拟结果与试验观测现象基本吻合。
简介:Thispaperfirstpresentsthestabilityanalysisoftheoreticalsolutionsforaclassofnonlinearneutraldelay-differentialequations(NDDEs).Thenthenumericalanalogousresults,ofthenaturalRunge-Kutta(NRK)methodsforthesameclassofnonlinearNDDEs,aregiven.Inparticular,itisshownthatthe(k,l)-algebraicstabilityofaRKmethodforODEsimpliesthegeneralizedasymptoticstabilityandtheglobalstabilityoftheinducedNRKmethod.
简介:描述行星规律的R-L矢量在笔者所见的文献中只指出了它的方向但末证明,本文对其加以了证明;并在此基础上比较简略地计算了它的大小;进而讨论了它的物理意义。
简介:ImplicitRunge-Kuttamethodishighlyaccurateandstableforstiffinitialvalueproblem.ButtheiterationtechniqueusedtosolveimplicitRunge-Kuttamethodrequireslotsofcomputationalefforts.Inthispaper,weextendtheParallelDiagonalIteratedRungeKutta(PDIRK)methodstodelaydifferentialequations(DDEs).WegivetheconvergenceregionofPDIRKmethods,andanalyzethespeedofconvergenceinthreepartsfortheP-stabilityregionoftheRunge-Kuttacorrectormethod.Finally,weanalysisthespeed-upfactorthroughanumericalexperiment.TheresultsshowthatthePDIRKmethodstoDDEsareefficient.
简介:1.IntroductionConsidertheinitialvalueproblemwhichisassumedtohaveauniquesolutiony(t)ontheinterval[0,+co).Forsolving(1.1),considerthes--stageimplicitRunge-Kutta(IRK)methodandthes-stagemono-implicitRunge-Kutta(MIRK)method{2,51swhereh)0isthestepsize,hi,c...
简介:Runge-Kuttamethodiswidelyappliedtosolvetheinitialvalueproblemofordinarydifferentialequations.TheimplicitRunge-Kuttawithbetternumericalstabilityforthenumericalintegrationofstiffdifferentialsystems,buttheformulatehastraditionallybeenonsolvingthenonlinearequationsresultingfromamodifiedNewtoniterationineverytime.Semi-implicitformulatehavethemajorcomputationallyadvantagethatitisnecessarytosolveonlylinearsystemsofalgebraicequationstofindtheKa.
简介:HighlyunderexpandedaxisymmetricjetwassimulatedusingtheRunge-KuttaDiscontinuousGalerkin(RKDG)finiteelementmethod,which,basedontwo-dimensionalconservationlaws,wasusedtosolvetheaxisymmetricEulerequations.Thecomputedresultsshowthatthecomplicatedflowfieldstructuresofinterest,includingshockwaves,slipstreamsandthetriplepointobservedinexperimentscouldbewellcapturedusingtheRKDGfiniteelementmethod.Moreover,comparisonsoftheMachdisklocationexhibitexcellentagreementsbetweenthecomputedresultsandexperimentalmeasurements,indicatingthatthismethodhashighcapabilityofcapturingshockswithoutnumericaloscillationandartificialviscosityoccurringnearthediscontinuouspoint.
简介:Inthispaper,basedontheimplicitRunge-Kutta(IRK)methods,wederiveaclassofparallelschemethatcanbeimplementedontheparallelcomputerswithNs(Nisapositiveevennumber)processorsefficiently,anddiscusstheiterativelyB-convergenceoftheNewtoniterativeprocessforsolvingthealgebraicequationsofthescheme,secondlywepresentastrategyprovidinginitialvaluesparallellyfortheiterativeprocess.Finally,somenumericalresultsshowthatourparallelschemeishigherefficientasNisnotsolarge.
简介:在这篇论文,为解决单个延期的二拍子的圆舞连续性Runge-Kutta(TSCRK)方法的一个班微分方程(DDE)被介绍。方法被给的这的数字稳定性的分析。我们考虑二个不同盒子:(ⅰ)τ≥h,(ⅱ)τ
简介:延迟微分代数方程(DDAEs)广泛出现于科学与工程应用领域.本文将多步Runge-Kutta方法应用于求解线性常系数延迟微分代数方程,讨论了该方法的渐近稳定性.数值试验表明该方法对求解DDAEs是有效的.
简介:摘要:本文试图对现象学中的“现象”进行较为系统的分析。通过与传统哲学如胡塞尔、海德格尔的现象涵义进行对比,作者采用阐释学的研究方法,人类大脑的记忆模式着手,以直观的结构图为手段,从“现象”的时间、空间范围属性对其进行了解读。现象学德语是phnomenlogie,英文是phenomenology,出现在二十世纪初期,由犹太裔德国人胡塞尔(EdmundHusserl)创立。简而言之,“现象学是一门关于现象的学问”。①提及现象学,人们就会想到“现象即本质”这一哲学论断,然而,此“现象”绝非传统哲学中“通过现象看本质”的彼“现象”。在传统哲学中,现象是事物表现出来的,能被人感觉到的一切情况。现象是人能够看到、听到、闻到、触摸到的。它们不依赖于认得意识而独立存在。按照划分,现象可分为自然现象和社会现象。如月亮东升西落、刮风下雨、苹果落地、太阳是圆的、狗长四条腿、人长两只手、人类的产生与灭亡、人的生死,都是自然现象;如战争、犯罪、起义、资本主义的产生与灭亡、国家的产生与灭亡、贫富分化、通货膨胀,都是社会现象。人们在实践中,通过大量的外部现象,可以认识或发现客观规律。这里的现象与本质之间是既有区别又有联系的……