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  • 简介:Inthispaper,westudyaclassofdynamicalsystemsinRn-idealsystemsandgiveanexistencecriterionofquasi-connectingorbitsforsuchsystems.Also,anexistencecriterionofconnectingorbitsforgeneralsystemsisgiven.

  • 标签: 准连续轨道 正则绝缘板块 临界点 微分方程
  • 简介:TheexistenceofatleasttwohomoclinicorbitsforLagrangiansystem(LS)isproved,wheretheLagrangianL(t,x,y)=1/2∑aij(x)yiyi-V(t1x),inwhichthepotentialV(t,x)isgloballysurperquadraticinxandT-periodicint.TheConcentration-CompactnessLemmaandMinimaxargumentareusedtoprovetheexistences.

  • 标签: 拉格朗日系统 超二次方程增长性 极小极大论 同宿轨
  • 简介:AparallelhybridlinearsolverbasedontheSchurcomplementmethodhasthepotentialtobalancetherobustnessofdirectsolverswiththeefficiencyofpreconditionediterativesolvers.However,whensolvinglarge-scalehighly-indefinitelinearsystems,thishybridsolveroftensuffersfromeitherslowconvergenceorlargememoryrequirementstosolvetheSchurcomplementsystems.Toovercomethischallenge,weinthispaperdiscusstechniquestopreprocesstheSchurcomplementsystemsinparallel.Numericalresultsofsolvinglarge-scalehighly-indefinitelinearsystemsfromvariousapplicationsdemonstratethatthesetechniquesimprovethereliabilityandperformanceofthehybridsolverandenableefficientsolutionsoftheselinearsystemsonhundredsofprocessors,whichwaspreviouslyinfeasibleusingexistingstate-of-the-artsolvers.

  • 标签: SCHUR补 线性系统 混合动力 系统系统 求解器 并联式
  • 简介:Thispaperdealswithabsorbingboundaryconditionsforhyperbolicsystemsinoneandtwospacedimensions.Weprovethestrictwell-posednessoftheresultinginitialboundaryvalueproblemin1D.AfterwardsweestablishtheGKS-stabilityofthecorrespondingLax-Wendroff-typefinitedifferencescheme.Hereby,wehavetoextendtheclassicalproofs,sincethe(discretized)absorbingboundaryconditionsdonotfitthestandardformofboundaryconditionsforhyperbolicsystems.

  • 标签: 吸收边界条件 双曲系统 双曲型 初始边界值问题 有限差分格式 二维空间
  • 简介:Theauthorsinvestigatetheglobalpropertiesofgeneralautonomoussystemsontheplaneandestablishcriteriaforthenonexistence,existenceanduniquenessoflimitcycles.Asapplicationexamples,thelimitcyclesforsomepolynomialsystemsarestudied.

  • 标签: 平面自治系统 存在性 唯一性 极限环
  • 简介:THEDISTURBANCELOCALIZATIONPROBLEMFORSINGULARSYSTEMSTanLiansheng(WuhanInst.ofMath.Sci.,Chin.Acad.ofSci.,Wuhan430071,China.)Abs...

  • 标签: SINGULAR system DISTURBANCE localilation INVARIANT SUBSPACE
  • 简介:InthispaertheinequalityofLemma1of[1]isextended.BymeansofourinequalityandthemethodofLyapunovfunctionwestudythestabilityoftwokindsoflargeseatedifferentialsystemswithtimelagandthestabilityofahigher-orderdifferentialequationwithtimelag.Thesufficientconditionsforthestability(S.),theasymptoticstability(A.S.),theuniformlyasymptoticstability(U.A.S)andtheexponentialasymptoticstability(E.A.S.)ofthezerosolutionsofthesystermsareobtainedrespectively.

  • 标签: 时滞偏微分 渐进稳定性 不平衡性 连续矩阵
  • 简介:Inmechanics,bothclassicalandquantum,onestudiestheprofoundinteractionbetweentwotypesofenergy,namely,thekineticenergyandthepotentialenergy.Theformercanbeorganizedasthekinematicmetricontheconfigurationspacewhilethelattercanberepresentedbyasuitablepotentialfunction,suchastheNewtonianpotentialincelestialmechanicsandtheCoulombpotentialinquantummechanicsofatomicandmolecularphysics.Inthispaper,theauthorstudiesthekinematicgeometryofn-bodysystems.Themainresultsaxe(i)theintroductionofacanonicalcoordinatesystemwhichrevealsthetotalamountofkinematicsymmetrybyanSO(З)×O(n-1)actioninsuchacanoniealcoordinaterepresentation;(ii)anindepthanalysisoftheabovekinematicsystembothinthesettingofclassicalinvarianttheoryandbythetechniqueofequivarjantRiemanniangeometry;(iii)aremarkablysimpleformulaforthepotentialfunctioninsuchacanonicalcoordinatesystemwhichrevealsthewell-fittingbetweenthekinematicsymmetryandthepotentialenergy.

  • 标签: 运动几何学 体系统 配置空间 量子论
  • 简介:<正>Inthispaperwegivethenecessaryandsufficientconditionsforallfinitecriticalpointsofquadraticdifferentialsystemstobeweakfoci,andsolveanopenproblemproposedbyYanqianYe.

  • 标签: QUADRATIC DIFFERENTIAL system LIMIT CYCLE Ergodicity.
  • 简介:Amaximumprincipleisprovedforsemilinearstochasticevolutionsystems.Themaincontributionofthisworkisthatinourproblem,theinfinitesimalgeneratorofthesemigroupofthesystemsneednottobeelliptic.ThisgeneralizesaresultofA.Bensoussanin1983.

  • 标签: SEMILINEAR elliptic STOCHASTIC generator SEMIGROUP proof
  • 简介:Borderedlinearsystemsarisefrommanyindustrialapplications,suchasreservoirsimulationandstructuralengineering.TraditionalILUpreconditionerswhichthrowawaytheadditionalequationsareoftentoocrudeforthesesystems.WedescribeapracticalimplementationofILUpreconditionerswhicharemoreaccurateandmorerobust.Theemphasisofthispaperisonimplementationratherthanontheory.

  • 标签: ILU PRECONDITIONER red-black ORDERING preprocessing.
  • 简介:Inthispapertheauthordiscussesthevectorfieldssatisfyingtheconditions(C1)and(C2)andprovessometheoremsforthenumberoflimitcyclesoftheplaneautonomoussystems.Someapplicationsofthetheoremsandlemmasin§1aregivenin§2.

  • 标签: satisfying AUTONOMOUS isola LEMMA 三一 edition
  • 简介:Ahybridtriplesystemofordervandindexλ,denotedbyHTS(v,λ),isapair(X,B)whereXisav-setandBisacollectionofcyclictriplesandtransitivetriplesonX,suchthateveryorderedpairofXbelongstoλtriplesofB.AnoverlargesetofdisjointHTS(v,λ),denotedbyOLHTS(v,λ),isacollection{(Y\{y},Ai)}i,suchthatYisa(v+1)-set,each(Y\{y},Ai)isanHTS(v,λ)andallAisformapartitionofallcyclictriplesandtransitivetriplesonY.Inthispaper,weshalldiscusstheexistenceproblemofOLHTS(v,λ)andgivethefollowingconclusion:thereexistsanOLHTS(v,λ)ifandonlyifλ=1,2,4,v≡0,1(mod3)andv≥4.

  • 标签: 三元系超大集 混合动力系统 高温超导 不相交 十字架 传递
  • 简介:LetGbeasecondcountablelocallycompactgroupoidwithHaarsystem{λuH},HbeaclosedsubgroupoidcontainingG^0withHaarsystem{λuH}.T.MasudaintroducedtheC^*-Groupoiddynamicsystem(G,A,α)anditsreducedcrossedproductCrea(G,A)in[2]:whereAisC^*-algebraαisthekomomorphismG→Aut(A).InthispapertheauthorintroducestheC^*-groupoiddynamicsystems(H,A,α/H)and(H\G2,A,^-α)inducedby(G,A,α)andprovesthatC*red(H,A)andC^*red(H\G^2,A)arestronglyMoritaequivalentMoreovertheinducedrepresentationfromC^*red(H,A)toC^*red(G,A)isgot.

  • 标签: C^*-群力学系统 听觉系统 群代数 交叉乘积
  • 简介:Singularlyperturbedproblemsforthenonlineardliptiesystemsinastripdomainareconsidered.Undersuitablaconditions,byusingthecomparisontheorem,theexistenceandasymptoticbehaviorofsolutionfortheboundaryvalueproblemsarestudied.

  • 标签: 奇异摄动系统 非线性 椭圆系统 带域