简介:<正>Foranoddfunctionf(x)definedonlyonafiniteinterval,thispaperdealswiththeexistenceofperiodicsolutionsandthenumberofsimpleperiodicsolutionsofthedifferentialdelayequation(DDE)(?)(t)=-f(x(t-1)).Byuseofthemethodofqualitativeanalysiscombinedwiththeconstructingofspecialsolutionsaseriesofinterestingresultsareobtainedontheseproblems.
简介:§1.IntroductionLetEbeanon-zerocomplexBanaohspace,&(JET)theBanaohalgebraofalltheoperatorsfromEintoitself.Operatormeans'boundedlinearoperator'throughout.Anoperatorfunction/fromadomain(openset)Dinthecomplexplaneto@l(T£}issaidtobeanalytic,ifforanyx^Eandq>£E*(thedualspaceofE\9>(/(z)aOisanalyticintheclassical’senseinD([1],p.92).Wedenotebyja/B(D)thesetofalltheanalyticoperatorfunctionsfromDinto
简介:InthispaperweestablishsharpH¨olderestimatesofharmonicfunctionsonaclassofconnectedpostcriticallyfinite(p.c.f.)self-similarsets,andshowthatfunctionsinthedomainofLaplacianenjoythesameproperty.Somewell-knownexamples,suchastheSierpinskigasket,theunitinterval,thelevel3Sierpinskigasket,thehexagasket,the3-dimensionalSierpinskigasket,andtheVicseksetarealsoconsidered.
简介:LetGbeagraphwithvertexsetV(G)andedgesetE(G)andletgandfbetwointeger-valuedfunctionsdefinedonV(G)suchthat2k-1≤g(x)≤f(x)forallx∈V(G).LetHbeasubgraphofGwithmkedges.Inthispaperitisprovedthatevery(mg+m-1,mf-m+1)-graphGhas(g,f)-factorizationsrandomlyκ-orthogonaltoHandshownthattheresultisbestpossible.
简介:LetB(E,F)bethesetofallboundedlinearoperatorsfromaBanachspaceEintoanotherBanachspaceF,B+(E,F)thesetofalldoublesplittingoperatorsinB(E,F)andGI(A)thesetofgeneralizedinversesofA2B+(E,F).InthispaperweintroduceanunboundeddomainW(A,A^+)inB(E,F)forA2B+(E,F)andA^+2GI(A),andprovideanecessaryandsufficientconditionforT2W(A,A^+).Thenseveralconditionsequivalenttothefollowingpropertyareproved:B=A^+(IF+(T??A)A^+)??1isthegeneralizedinverseofTwithR(B)=R(A^+)andN(B)=N(A^+),forT2W(A,A^+),whereIFistheidentityonF.Alsoweobtainthesmooth(C¥)diffeomorphismMA(A^+,T)fromW(A,A^+)ontoitselfwiththefixedpointA.LetS=fT2W(A,A^+):R(T)\N(A^+)=f0gg,M(X)=fT2B(E,F):TN(X)R(X)gforX2B(E,F)g,andF=fM(X):8X2B(E,F)g.UsingthediffeomorphismMA(A^+,T)weprovethefollowingtheorem:SisasmoothsubmanifoldinB(E,F)andtangenttoM(X)atanyX2S.ThetheoremexpandsthesmoothintegrabilityofFatAfromalocalneighborhooldatAtotheglobalunboundeddomainW(A,A^+).Itseemstobeusefulfordevelopingglobalanalysisandgeomatricalmethodindifferentialequations.
简介:Analgorithmofcontinuousstage-spaceMCMCmethodforsolvingalgebraequationf(x)=0isgiven.Itisavailableforthecasethatthesignoff(x)changesfrequentlyorthederivativef'(x)doesnotexistintheneighborhoodoftheroot,whiletheNewtonmethodishardtowork.Letnbethenumberofrandomvariablescreatedbycomputerinouralgorithm.Thenafterrn=O(n)transactionsfromtheinitialvalueXo,X^*canbegotsuchthat[f(x^*)|<e-^cm|f(xo)|bychoosingsuitablepositiveconstantc.Anillustrationisalsogivenwiththediscussionofconvergencebyadjustingtheparametersinthealgorithm.
简介:TheauthorsmainlyconcernthesetUfofc∈Csuchthatthepowerdeformationzf(z)/zcisunivalentintheunitdisk|z|<1foragivenanalyticunivalentfunctionf(z)=z+a2z2+···intheunitdisk.ItisshownthatUfisacompact,polynomiallyconvexsubsetofthecomplexplaneCunlessfistheidentityfunction.Inparticular,theinteriorofUfissimplyconnected.Thisfactenablesustoapplyvariousversionsoftheλ-lemmafortheholomorphicfamilyzf(z)/zcofinjectionsparametrizedovertheinteriorofUf.ThenecessaryorsufficientconditionsforUftocontain0or1asaninteriorpointarealsogiven.