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1.
ON THE GROWTH OF SOLUTIONS OF A CLASS OF HIGHER ORDER DIFFERENTIAL EQUATIONS   总被引:12,自引:0,他引:12  
In this paper, authors investigate the order of growth and the hyper order of solutions of a class of the higher order linear differential equation, and improve results of M. Ozawa^[6], G. Gundersen^[7] and J.K. Langley^[8], Li Chun-hong^[11].  相似文献   

2.
1IntroductionConsiderableattelltionhasbeendevotedtotilesemigroupoftheelldomorphislllsofagraph,inparticular,thesemigroupofthestrongendomorpllisnasofagraph,seesurvey[1].Themainpurposeoftheseresearchesliesintheapplicatiollsofthealgebraictheoryofsendgroupstothetheoryofgraphs.ItiswellknowllthatoneofthemostimportantconceptsillselltigrouptheoryisGreen'srelations.In[2],thecharacterizatiollofGreen'srelationsonsEnd(G),themolloidofthestrongendomorphisnisofagrapllG.isgiven.LetSbeasemigroup.Thenotation…  相似文献   

3.
1.IntroductionandMainResultThenonlinearSchr6dingerequationshavebeenextensivelystudiedin[3,5,6,8,9],whereequationsareofthefollowingtype:In[l],anothertypeofequationshasbeenstudiedSincetheequalityofenergydoesnothold,theGalerkinmethodisused.Inthispaper)wewillstudythepropertyofequationsofthe'secondtype,wherewemakethechoiceoffi=R:.BecauseoftheunboundednessofR',wecannotusetheGalerkinmethod,andweuseothermethodtoobtaintheaDDroximatesolutions.Inthispaper,firstlyweconsidertheglobalweaksolutionsofthe…  相似文献   

4.
1IntroductionInthepresentpaper,weconsidertheuniquenessofsolutionforthetransportationsystemwithinitialdatawherepanduaredensityandvelocityrespectively.Thesystemofcollservationlaws(1.l)describesthefluidmechanicswithconstantpressure,whichisusedinplasmaphysicswhosepressureisassumedtobeconstant.TheCauchyproblemforthissystemisnotwell-posedintheclassofboundedmeasurablefunctions(see[31).In[8],Z.Wang,F.HuangandX.DinghaveprovedtheealstenceofsolutionsdefinedbyLebesgue--Stieltjesintegral.Beforedetaildi…  相似文献   

5.
In [1] we investigated the problems of calculus of variations with strong non-linearity. In[2] we already indecated its Euler equation is evidently the following elliptic type equation of divergent form with strongly increasing coefficient  相似文献   

6.
1.IntroductionRecentlythestudyofdiscontinuoussolutionforthesystemofconservationlawsinhigherdimensionalspacehasbeenconsiderablydeveloped.In[1,W12]thelocalekistenceof8olutionforsuclisystemwithdiscontinuityinvolvingsingleshock,rarefactionwaveorsoundwav(gradientwave)hasbeenestablished.In[2Jand[14]theproblemsoninteractionoftwoshocksorinteractionofweaksingularitiesarealsoconsidered.Itisnaturaltoaskwhatabouttheresultwhenashockisinteractedbyawavewitliweakersillgularities,particularly,forthenbynsystem…  相似文献   

7.
In this paper, a class of nonlinear difference equations are investigated. The sufficient conditions for the nonexistence of positive solutions are obtained. The results in this paper improve ones in [2].  相似文献   

8.
PROPERTIES OF FRACTIONAL k-FACTORS OF GRAPHS   总被引:1,自引:0,他引:1  
In this paper the properties of some maximum fractional [0, k]-factors of graphs are presented. And consequently some results on fractional matchings and fractional 1-factors are generalized and a characterization of fractional k-factors is obtained.  相似文献   

9.
0 IntroductionRecently, the study of ordinary differential equations in a Banach spacehas been developed extensively by using the strong topology, see [2],13],[4]. Atpresent, however, there is no reference or paper which systematically studiesweak solutions of the Cauchy problem of ordinary differential equation in theweak topology. In references [l],15],[7] and [8], several results of weak solutionsare proved. In this paper, we shall give the other results of weak solutions,some of which are…  相似文献   

10.
In the present paper we study properties of Szász-Durrmeyer operators. These operators are introduced in [5] and generalize the integral operators proposed by S.M.Mazhar and V.Totik in [12]. We also generalize some results obtained by M. Heilmann[6] and D.-X. Zhou[16].  相似文献   

11.
51.IntroductionandtheMainTheoremLetXbeacomplexnonsingularminimalprojectivethreefoldofgeneraltype.ThenatureofpluricanonicalmapsofXisveryimportanttotheclassificationtheory.Itiswell-knownfrom[10]that4linK.lisabirationalmapform27.In[3],itisprovedthat6-canonicalmapofXisabirationalmapontoitsimage.Inthispaper,wemainlystudythefollowingproblem:Problem.WhatisthegreatestpositiveintegercosuchthatImoKxliscomposedOjapencilOjsudecesforsomeX,i.e.,dim4Im.H.I(X)=1?Benv.ni,te[1]provedthatmo53.Wecaneasily…  相似文献   

12.
1.IntroductionRecentlymanyresultshavebeenobtainedfordistributedbilinearsystemsl3'7'8].In[3]thecontrollabilityofabilinearsystem%=Aw(t) p(t)Bw(t)wasstudied,whereAistheindnitesimalgeneratorofaCosemigroupofboundedlinearoperatorsT(t)onaBanachspaceX.B:X-- 5isaboundedlinearoperator,andpELI([0,T];R)isacontrol.TheconditionsforelementsofEtobeaccessiblefromagiveninitialstatecoweregiven.Itisclearthattheystudiedthebilinearsysteminaspecialcase.In[8]theystudiedthesysteminamorespecialcasebecausetheyass…  相似文献   

13.
51.IntroductionAnembeddingofacoveringmaporaprincipalG-bundleT:E- Xintoavectorbundlep:V→XisamapH:E-VwhichmapsEhomeomorphicallyontoitsimageH(E)inVsuchthatpoH=7.In[6l,HansenprovedthatanyfinitecoveringmapoveraCW-complexcanbeembeddedintothetrivialrealm-planebundleifdimX5m 1.Embeddingfinite..covringmapsintoarbitraryvectorbundleswasconsideredbyDuval1andHuschl3].Suchanembeddingproblemwasalsodiscussedin[4,5,6,7,8,11,12]and[13].Inthisnote,thefirstpoilltistostudyingreaterdepththeembeddingproble…  相似文献   

14.
In this paper the properties of some maximum fractional [0, κ]-factors of graphs are presented. And consequently some results on fractional matchings and fractional 1-factors are generalized and a characterization of fractional k-factors is obtained.  相似文献   

15.
Since 1980,Bellman inequality was put forward.This arises attention.In[2,3,4,5]there were some good results presented.In this paper we shall obtain the Bellman in-equality of simplicial matrices.  相似文献   

16.
In this paper, by using Mawhin coincidence degree, some sufficient conditions are obtained for the global existence of positive periodic solution of a mutualism system with infinite delays. Our results generalize those of Yang etc. [8] and Gopalsamy and He [7].  相似文献   

17.
In this paper, the author considers Lienard's equation, studies the properties of so-called characteristic functions and gives three theorems which ensure that the equation has at least one limit cycle. The theorems generlize Filippov's Theorem which is a repesentative result, Dragilev's Theorem, Theorem 1, 2 of[6], Theorem 9 of[8] and Theorems 1, 2 of[9] respectively.  相似文献   

18.
1.IntroductionPersistenceofpopulationsplaysanimportantroleinmathematicalecology.Inrecentyears)muchattentionhasbeengiventothepersistenceofnonautomonouspopulationmodelsll--6].[1]proposedtheconceptofpersistenceinthemeanofpopulations.Thisisofimportancebecausenotonlyitprovidesawaytocharacterizethepersistenceofpopula-nons,butalsothereareonlythresholdsbetweenpersistenceinthemeanandtheextinctionofpopulationsforgeneralnonautomonouspopulationmodels.In[2]thethresholdwasestablishedforone-dimensionalnonaut…  相似文献   

19.
In this paper, an instability criteria for nonlinear ordinary vector differential equation (1.1) is given. The result extends and includes the results of previous authors in ([1], [27]).  相似文献   

20.
AMSSubjectClassification34C27Thespatialelementinpopulationbiologyisimportanttounderstandthedynamicsofecologicalsystems.ThetheoreticalworksonthisproblemwerepioneeredbySkellamif]in1951andwerereviewedbyLevin[2]in1974.In12],Levinfirstestablishedthiskindofmode…  相似文献   

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