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1.
§1 . IntroductionTheclassicalelastictheorydealswithacurveinR2 orR3 whichisacriticalpointforthetotalsquaredcurvaturefunctionalonregularcurveswithfixedlengthsatisfyinggivenboundaryconditions.ThiscouldtracebacktoDanielBernoulli( [1]) .Duringrecenttwodecades,severalauthors( [2 ],[3],[4 ])consideredthegeneralizationsoftheelasticatothespaceforms.ThispaperdealswiththeaffinestarlikecurvesinR2 .Westudythecriticalpointforthetotalpolynomialsubaffinecurvaturefunctionalonthosestarlikecurvessatisfyingg…  相似文献   

2.
增算子固有值问题的多重解   总被引:1,自引:1,他引:0  
杜一宏 《数学学报》1988,31(1):21-28
<正> §1.引言与基本引理 设P为Banach空间E中正规体锥,A:P→P为全连续算子,它单调增且Aθ>>θ.我们考虑固有值问题 λAx=x,λ∈([0,+∞),x∈P(1) 关于(1)的解的存在性及解的个数,已有不少讨论,例如参看文献[1],[6],[7],[12]等.众所周知,对较大范数的x,给Ax以限制,如A渐近线性,则常常导致出现多重解的情况(参看[1],[6],[7],[8],[9]等).本文研究(1)存在多重解的一些新的情  相似文献   

3.
1IntroductionWeconsiderinthispapertwo-dimensionalautonomoussystemsofdifferentialequationsoftheformwhere'=2,p(x,y)andQ(x,y)arepolynomials,i.e.wherePh(x,y)andoh(x,y)arehomogeneouspolynomialsofdegreek.Thetwofundamentalproblemsofthequalitativetheoryofsystem(1)aretheproblemofthecenterandthedeterminationofthenumberoflimitcyclesandtheirlocationinphasespace.Inrecentworksithasbeenshownthataunifiedmethodcanbeusedtostudytheseproblems[2],[3],[4],[6],[8]and[12](andreferencestherein).Themethodisbasedonthed…  相似文献   

4.
李森林 《数学学报》1965,15(2):217-226
<正> 零解的稳定性,还没有一般解决的方法.许多研究工作者,都寻求保证解的稳定的充分条件.例如[1],[2],[3],[4]等等.事实上,要验证上述方法的条件是否满足,亦非常困难.如[1]要求已知方程的特征方程的根均具有负实部,因而必须验证 n 阶行列式(含 t)的不  相似文献   

5.
§ 1. Introduction  Let(M ,T)beasmoothinvolutiononasmoothclosedmanifold ,andFdenotesthefixedpointsetof (M ,T) .WhenF =RP( 2k) ,RP(m)∪RP(n) ,∪RP( 2l+ 1 ) (lfixed) ,∪pi =1 RP( 2li+ 1 ) ,∪ri =1 (S1 ) ki ,(Sn1 ×Sn2 ×… ×Snp)∪ {pt},etc .,theexistenceandtherepresentative (uptobordism)of(M ,T)havebeenstudiedin [2 ],[3],[5 ],[6],[7]and[8].Thepurposeofthepaperistodeterminetheexistenceandtherepretentativeuptobord ismofallinvolutionsfixingthelensspaceL1 ( p) ,whereL1 ( p)isa 3 dimens…  相似文献   

6.
林正国 《数学学报》1984,27(6):830-833
<正> 谷超豪在[1],[2],[3]中得到了拟线性正对称组边值问题的 C~ρ解的存在和唯一性定理.陈恕行在[4],[5]中讨论了拟线性对称双曲组的初边值问题.本文继[1]—[5],讨论拟线性正对称组的特征边值问题.  相似文献   

7.
<正> 在文章[2],[3],[4],[5]中已对任何N>n>1及0≤δ≤1/2(以下总假设上列不等式满足)研究了最优分批问题的满足[2]中定理5.1的条件组  相似文献   

8.
周言 《数学学报》1987,30(3):303-316
<正> (μ,△,γ)-系统的正则分类在A_n~2(n≥2)多面体同伦分类中有重要应用,见[1],[2],[3].文[4],[5],[6]和[2]通过确定系统的完全不变量对某些类型(μ,△,γ)-系统作了正则分类.本文采用类似的方法对另一类型(μ,△,γ)-系统作了正则分类,并且对由两条不同途径获得的两套完全不变量作了精确的比较.  相似文献   

9.
1IntroductionBBMequatiollbut box~'uxxt=0,x6R,t>0,(l.1)isderivedinnonlineardispersivesystemsbyT.B.Benjamin,J.H.L.BonaandJ.J.Mahony'asamodelequationforlongwaves.TheypointedoutthatthismodelismoresuitabletoreplaceKDVequation(see[2],[4]).BOequationILt 2'UU. HU.:.=0,XER,t>0,(1.2)arisesinthestudyoflollginternalgravitywavesilldeepstrafiedfluids(see[51,[9]).Bothofthelllarewell-kllownandhavebeenwidelystudied(see[31,[10],[11],[12]).Inthispaper,wecollsiderthefollowingBBM-BOtypeequationwithini…  相似文献   

10.
秦铁虎 《数学学报》1984,27(6):855-859
<正> 楔状区域是一类谷超豪在[5]中所讨论的具空向边缘区域,边界上有非良性角点(见[1],[6]).这种区域也可视为李大潜与俞文(鱼此)在[3],[4]中讨论过的在二维情况的角状区域的拓广.  相似文献   

11.
§1. IntroductionThereseachindetailonlinearrecurringsequencesovertheresideclassringZ/(pe)start-edfromWardworkin30s(see[1]).Inthepastfewyears,fromthepointofviewofcrypto-graphandcodetheory,peopleisinterestedparticularlyinstudyingthecoordinatesequencesde-rivedfromML-sequencesoverZ/(pe),asnon-linearrecurringsequencesoverFp(see[2],[3]).SomeanalogousresultsextendedtoGaliosringcanbefoundin[4],[5].Butthereisnobetterresultontheresearchofthe0,1-distributionproperties.Fromavastamountofcalcula-tion,t…  相似文献   

12.
Whenmulticollinearityexists,theordinaryleastsquares(OLS)methodbecomesinefficient.TOavoidthis,partialleastsquares(PLS)regressionisdeveloped(see[2],[4]or[6-8]).Butlikeotherregressionmethods,thePLSfittingcouldbesubstantiallyalteredbyoneorafewinfluentialpoints.Inthispaper,asecondorderlocalapproach(see[1],[9]or[10])isthemaintooltoidentifyinfluentialpointsinPLSregression.LetYbethenx1responsevector,andXtheknownnxpexplanatorymatrix.WhenfitthemodelY~Xo 55whereE~N(0,a'In),wewritetheperturbeddis…  相似文献   

13.
1.IntroductionTheZakharovequationsdescribephysicalphenomenainPlas,,,.112].TheglobalexistenceofaweaksolutionfortheZakharovequationswascollsideredbySulemandSulelnin[11].Theexistenceanduniquenessofasmoothsolutioninonedimensionareprovedprovidedthatsmoothinitialdataaredescribed.Forsmallinitialdata,theexistenceofaweaksolutionfortheZa,kharovequationsintwoandthreedimensionsisobtained.NumericalmethodsfortileZakharovequationsinonedimensionwereconsideredin[l],[2],[4],[5]and[10].Aspectralmethodisusedt…  相似文献   

14.
1.IntroductionLinearandn0Iilinearc0mplementarityproblemshavemanyimportanaPplications.-invaxi0usfieldssuchasec0nomics,transportationetc.,theyhaveattractedmuhat-tentionsinceearly1960's.AstandardnonlinearcomplementarityProblemistofindaxEMsuchthat:F(x)20,x2O,x"F(x)=0,(1'1)whereF:R"-R".Forsimplicity,weoftencallitNCP.Manyauthorshavestudiedthisproblemandencouragingresultshavebeenreported.Onecanfindanexcellentlycompletesummaryf0ritin[2].Forrecentworks,see[7],[9],[3],[81.Thegeneralizedcomplement…  相似文献   

15.
噪声数据拟合与谱估计的极大互息原理   总被引:1,自引:0,他引:1  
§1.引言由于极大熵方法的 AR 拟合和谱估计不考虑观测数据中噪声的影响,许多实际问题的谱分析和模型拟合效果不好.近年来[1]—[4],[12],[13]讨论了观测  相似文献   

16.
孙兴旺  代新利 《数学季刊》2003,18(4):378-387
§ 1. IntroductionRecently ,thedifferentialequationswithdeviatingargumentswereusuallydiscussed(see[1 ],[4],[5 ]) .In [1 ],AGARWALRPandO’REGANDconsideredequationy″(t) =f(t,y(t) ,y(σ(t) ) ) , a.e .t∈ [0 ,1 ]y(t) =ψ(t) ,        t∈ [-r ,0 ]y( 1 ) =a ,( )andtheydiscussedtheexistenceofatleastonesolutionforequation ( ) .Inthispaper ,weconsideramoregeneralequation-x″(t) =f(t ,xt) , t∈ [0 ,1 ]x(t) =ψ(t) ,    t∈ ( -∞ ,0 ]x( 0 ) =x( 1 ) =0 ,( 1 .1 )andsomeexistencetheor…  相似文献   

17.
汪忠志  徐付霞 《数学季刊》2003,18(4):343-348
§ 1. Introduction  ConsiderasequenceofBernoullitrials ,andsupposethatateachtrialthebettorhasthefreechoiceofwhetherornottobet.Asystemconsistsinfixedrulesselectingthosetrialsonwhichtheplayeristobet.ThetheoremongamblingsystemassertsthatunderanysystemthesuccessivebetsformasequenceofBernoullitrialwithunchangedprobabilityforsuccess.TheimportanceofthisstatementwasfirstrecognizedbyvonMises,whointroducedtheimpossibili tyofasuccessfulgamblingsystemasafundamentalaxiom(cf.[1 ],[2 ],[3],[4]) .Thecon …  相似文献   

18.
<正> §1.引言空间解析几何的一个重要研究内容是:如何判别一个曲面为旋转曲面;如果是旋转曲面,如何求旋转轴?根据文[1],[2],[3],[4],[5],[6]等等解析几何有关资料的介绍,、这方面的内容是极少见的,本文命题1给出二阶锥面是旋转曲面的条件,并求出旋转轴;命题2给  相似文献   

19.
<正> 1.引言文[1],[2],[3]对几种锁相环路方程作了定性研究,本文着重研究无噪声混合锁相环路方程的分界线环,并给出了分界线参数值的近似值,这可供实际工作者参考.而关于混合锁相环路的结构及数学模型可参看[5]第三章.  相似文献   

20.
1IntroductionTheabstractCauchyproblemsfordifferentialequationsonclosedsetshavebeenstudiedbymanyauthors(see[2],[3]).In[1],H.MonchandG.H.VOnHartonestablishedinequalitiesofmeasuresofnoncolnpactnessforthesequencesofcontinuouslydifferentiablefunctiofls,thed,us…  相似文献   

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