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198 个结果
  • 简介:WepressentnewKyFantypebestapproximationtheoremsforadiscontinuousmultivaluedmaponmetrizabletopologicalvectorspacesandhyperconvexspaces.Inaddition,fixedpointresultsarederivedforthemapstudied.Ourworkgeneralizesseverlresultsinapproximationtheory.

  • 标签: 近似值 定理 可度量化 向量空间
  • 简介:ThenonconformingWilson’sbrickclassicallyisrestrictedtoregularhexahedralmeshes.LesaintandZlamal[6]relaxedthisconstraintforthetwo-dimensionalanalonueofthiselementInthispaperweextendtheirresultstothreedimensionsandprovethatandwhereuistheexactsolution,u_histheapproximatesolutionandistheusualnormfortheSobolevspaceH~1(?).

  • 标签: CONVERGENCE NONCONFORMING Wilson’s BRICK hexahedral meshes.
  • 简介:Baker'syeastmediatedreductionofopticallyactivediketoneisdescribed.Thetwoketogroupsareefficientlydifferentiatedandtheeevalueoftherecoveredmaterialisconsiderablyraised.Itaffordshighlyopticallyactivekeyintermediatesefficientlyforthesynthesisofnaturalpolyhydroxylatedagarofuranproducts.

  • 标签: 酵母 沉香呋喃 倍半萜 简化
  • 简介:ItisprovedthateachsufficientlylargeintegerN≡5(mod24)canbewrittenasN=p12+p22+p23+p24+p25with|pj-√N/5|≤U=N1/2-1/35+ε,wherepjareprimes.Thisresult,whichisobtainedbyaniterativemethodandahybridestimateforDirichletpolynomial,improvesthepreviousresultsinthisdirection.

  • 标签: 素数 可加性 循环法 迭代法 幂积分表达式
  • 简介:TheauthorconsiderstheFeigenbaum'sfunctionalequationf^P(λx)=λf(x)foreachp≥2.TheexistenceofevenunimodalC^1solutionstothisequationisdiscussedandafeasiblemethodtoconstructsuchsolutionsisgiven.

  • 标签: 功能方程 连续单峰解 偶数单峰解 交叉迭代
  • 简介:Inthisworkweslwlylinearpolynomialoperatorspreservingsomeconsecutivei-convexitiesandleavingin-verantthepolynomtalsuptoacertaindegree.Firstwestudytheexistenceofanincompatibilitybetweentheconservationofcenaini-cotivexitiesandtheinvarianceofaspaceofpolynomials.InterpolationpropertiesareobtainedandatheorembyBerensandDcVoreabouttheBernstein’soperatortsextended.Finally,fromtheseresultsagenera’izedBernstein’soperatorisobtained.

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  • 简介:IntroductionWhenanalyzingthedynamicinteractionofasoil_structuresystem,thekeystepistocalculatethedynamicstiffnessmatrixoftheso...

  • 标签: transversely ISOTROPIC LAYERED ELASTIC STRATA Green’s
  • 简介:摘要刻画了|C(S)/L|≤2的完全正则半群S的同余格的具体特征,给出了具有上述性质的所有完全正则半群的分类.

  • 标签: 同余格 局部关系 分类
  • 简介:到HOCN的HNCO的反应,到HSCN的HNCS和到HSeCN的HNCSe在MP2/6-311++G被学习了(2df,pd)//B3LYP/6-311++G(2df,pd)水平。反应物,转变状态和产品的几何学被优化了,转变状态的几何学第一次被报导。HNCO和HNCS容易被检测而不是HOCN和HSCN的原因被解释了。HNCSe将更容易比HSeCN被检测,这被预言。在反应的化学契约的破裂和形成被电子密度的拓扑的分析方法讨论了。在反应有二种结构转变状态(圣)的计算结果表演学习了。

  • 标签: 分子结构 原子结构 原子物理 能级
  • 简介:ThispaperusesPoincaréformalismtoextendtheLevi-Civitatheoremtocopewithnonholonomicsys-temsadmittingcertaininvariantrelationswhoseequationsofmotioninvolveconstraintmultipliers.Sufficientcondi-tionsallowingsuchextensionareobtainedand,asanapplicationofthetheoryageneralizationofRouth’smotionispresented.

  • 标签: NONHOLONOMIC DYNAMICAL systems Levi-Civita’s THEOREM POINCARÉ
  • 简介:牛顿的重复为单个Toeplitz矩阵的组逆的计算被修改。在每次重复,重复矩阵被一个矩阵与一个低排水量等级接近。因为重复矩阵的排水量结构,涉及牛顿的重复的thematrix向量增加能高效地被做。我们证明修改牛顿重复的集中仍然是很快的。数字结果被介绍表明建议方法的快集中。

  • 标签: 牛顿迭代 群逆转 TOEPLITZ矩阵 位移秩
  • 简介:Small-angleX-rayscattering(SAXS)usingsynchrotronradiationasX-raysourcehasbeenemployedtocharactcizcthemicroscopicstructrureoforgano-modifiedmesoporousmolecularsieves(organo-MSU-X)preparedbyaone-pottemplate-directedsynthesis.ItisshownthattheSAXSprofileishardlyconstantwithPorod’slawshowinganegativeslope,i.e.,negativedeviation.Thissuggeststhatthereisdiffuseinterfaciallayerlocatedbetweentheporesandthematrix.Thissuggeststhattheorganicgroupsremaincovalentlylinkedtothematrix,asindicatedby^29SiCPMASNMRandFT-IR.Theaveragethicknessoftheinterfaciallayerwasfoundtobeabout1nmforeachofthethreesampleswithdifferentkindsandthesameamounts(20?oforganicgroups.Thiskindofmaterialhasalsobeenprovedtopossessbothsurfaceandmassfractalstructureoftheamophousporoussilicamaterials.2001ElsevierScienceB.V.Allrightsreserved.

  • 标签: 中孔材料 SAXS 小角X射线散射分析 界面层 结构特征 有机中孔分子筛
  • 简介:The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.

  • 标签: Duffing' s EQUATION SUBHARMONIC TRANSIENT PROCESS