学科分类
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312 个结果
  • 简介:分组数列问题形式新颖,构思精巧,题型丰富多彩,但离不开两个最基本的问题:求通项公式与前n项和.本文就这两个基本问题做如下的讨论.

  • 标签: 前N项和 数列问题 通项公式 分组
  • 简介:Inthispaperwewillshowthatifanapproximationprocess{Ln}n∈Nisshapepreservingrelativetotheconeofallk-timesdifferentiablefunctionswithnon-negativek-thderivativeon[0,1],andtheoperatorsLnareassumedtobeoffiniterankn,thentheorderofconvergenceofDkLnftoDkfcannotbebetterthann2evenforthefunctionsxk,xk+1,xk+2onanysubsetof[0,1]withpositivemeasure.Takingintoaccountthisfact,wewillbeabletofindsomeasymptoticestimatesoflinearrelativen-widthofsetsofdifferentiablefunctionsinthespaceLp[0,1],p∈N.

  • 标签: 渐近估计 N-宽度 线性相关 次可微函数 逼近过程 线性关系
  • 简介:Inthispaper,wedeterminetheexactestimationofone-sidedn-widthsdn+(wqr(pr),L1).q=1,∝,whereWqr(Pr)isaclassofdifferentiable2π-periodicfunctions,andisdeterminedbyadifferentialopera-torPr(D)=Dσ∏j=tl(D-αj),σ,j∈N,σ≥2,xj≠0,xj∈R.

  • 标签: DIFFERENTIABLE exact CLASSES opera sided Approximation
  • 简介:设G是一个具有顶点集V(G)和边集E(G)的图。设g和f是定义在V(G)上的两个整数值函数,使得g(x)≤f(x)对所有的点x∈V(G)都成立。结果G是一个(mg+n,mf-n)-图,1≤n

  • 标签: 因子分解 正交 整数值函数
  • 简介:ThecommutatorsofsingularintegraloperatorswithhomogeneouskernelΩ(x)/|x|^narestudied,whereΩishomogeneousofdegreezero,andhasmeanvaluezeroontheunitsphere.ItisprovedthatΩ∈L(logL)^(k+1)(S^(n-1))isasufficientconditionsuchthatthek-thordercommutatorisboundedonL^2(R^n).

  • 标签: 转接器 单一积分算子 有界平均振动 傅里叶变换
  • 简介:ThequalitativepropertiesofapredatorpreysystemwithHolling-(n+1)functionalresponseandafairlygeneralgrowthratearecompletelyinvestigated.Thenecessaryandsufficientconditiontoguaranteetheuniquenessoflimitcyclesisgiven.Ourworkextendsthepreviousrelevantresultsinthereference,

  • 标签: 极限环 唯一性 DULAC函数 充分条件
  • 简介:在通常情况下,对于任意的通道结构Γ的理想秘密共享方案不存在.然而,如果|Γ0|n成立,那么通道结构Γ便存在一个理想的秘密共享方案,其中Γ0是Γ的基,n是参与者总量.

  • 标签: 理想秘密共享方案 信息率 通道结构
  • 简介:R.A.Gordon在[1]中定义了从R^1到Banach空间抽象函数的McShane积分,证明了当X不含C0时,如果,在[a,b]上MeShanef可积,则在[a.b]上Pettis可积.在这篇文章中,我们定义了从R^n到Banaach空间抽象函数的Mcshane积分。证明了fMcShane可积,则f是Pettis可积.于是我们推广了[1]的结果。

  • 标签: 可积 积分 BANACH空间 证明 值函数 抽象函数
  • 简介:作者将证明组2Dp(3)能被它的顺序部件特别地决定,在此p≠2m+1是一个素数,p≥5。更精确,如果OC(G)表示G的顺序部件的集合,我们将证明OC(G)=是OC(2Dp(3))如果并且仅当G对2Dp(3)。我们的结果的主要后果是汤普森的有效性在考虑下面为这些组推测。

  • 标签: 素数 图表 次数成分 线性群
  • 简介:ThispapershowsthattheC1-curvedfiniteelementdevelopedbyBernadoningeneralcannotsatisfytheessentialboundaryconditionsonapproximateboundary.Furthermore,amodifiedC1-curvedfiniteelementisgiven,whichiscompatiblewiththeelementofArgyristriangleandcansatisfythehomogeneousDirichletboundaryconditionsonapproximateboundary.

  • 标签: Curved boundary DOMAIN Argyris TRIANGLES C1-curved
  • 简介:ThispaperintroducestheconceptoflocalC-cosins-familyandinverstigateitsbasicproperties,Inparticular,acharacterizationofthecompleteinfinitesimalgeneratorofalocalC-cosinefamilyisobtained,AsanapplieationofthistheorytothesecondordersbstractCauchyproblems,acharacterizationofthelocalC-well-posednessoftheseproblemsisgivenintermsofthelocalC-cosinefamilytheory.

  • 标签: 余弦族 完全生成元 二阶柯西问题 半群
  • 简介:LetιbeatriangulationofapolygonaldomainDR2withverticesV={v1:1≤i≤N,}andRSk(D,τ)={u∈Ck(D):(T∈τ,u|τisarationalfunction}.Thepurposeofthispaperistostudytheexist-enceandconstructionofCμ-rationalsplinefunctionsonanytriangulationτforCAGD.TheHermiteprob-lemHμ(V,U)={findu∈

  • 标签: TRIANGULATION spline CAGD polygonal rational vertex
  • 简介:Thispaperderivesfirstordernecessaryandsufficientconditionsforunconstrainedconed.c.Programmingproblemswheretheunderlinedspaceispartiallyorderedwithrespecttoacone.Theseconditionsaregivenintermsofdirectionalderivativesandsubdifferentialsofthecomponentfunctions.Moreover,conjugatedualityforconed.c.Optimizationisdiscussedandweakdualitytheoremisprovedinamoregeneralpartiallyorderedlineartopologicalvectorspace(generalizingtheresultsin[11]).

  • 标签: 锥d.c.最优化 共轭对偶 弱对偶定理 次梯度 多目标优化 方向导数
  • 简介:Weintroducethenotionofproperty(RD)foralocallycompact,Hausdorffandr-discretegroupoidG,andshowthatthesetS2^l(G)ofrapidlydecreasingfunctionsonGwithrespecttoacontinuouslengthfunctionIisadensespectralinvariantandFreehet*-subalgebraofthereducedgroupoidC^*-algebraCr^*.(G)ofGwhenGhasproperty(RD)withrespecttol,sotheK-theoriesofbothalgebrasareisomorphicunderinclusion.EachnormalizedcoeycleconG,togetherwithaninvariantprobabilitymeasureontheunitspaceGoofG,givesrisetoacanonicalmapTconthealgebraCo(G)ofcomplexcontinuousfunctionswithcompactsupportonG.WeshowthatthemapTccanbeextendedcontinuouslytoS2^l(G)andplaysthesameroleasann-traceonCr^*(G)whenGhasproperty(RD)andcisofpolynomialgrowthwithrespecttol,sotheConnes'fundamentparingbetweentheK-theoryandthecycliccohomologygivesustheK-theoryinvariantsonCr^*(G).

  • 标签: GROUPOID C^*-algebra property (RD) SPECTRAL INVARIANCE
  • 简介:A.simplicialmesh(triangulation)isconstructedthatgeneralizesthetwo-dimensional4-directionmeshtoR~m.Thismesh,withsymmetric,shift-invariantvaluesatthevertices,isshowntoadmitaboundedC~1interpolantifandonlyifthealternatingsumofthevaluesattheverticesofany1-cubeiszero.Thisim-pliesthaiinterpolationattheverticesofanm-dimensional,simplicialmeshbyaC~1piecewisepolynomialofdegreem+1withonepiecepersimplexisunstable.

  • 标签: invariant INTERPOLATION TRIANGULATION PIECEWISE symmetric cube