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500 个结果
  • 简介:让n≥2是一个固定积极整数,q≥3并且c是二个整数与(n,q)=(c,q)=1。我们由r表示n(δ1,δ2,c;q)(0<δ1,δ2≤1)都个整数的数字一,b令人满意的ab≡c(现代派的q),1≤≤δ1q,1≤b≤δ2q,(一,q)=(b,q)=1并且n†(+b)。这篇论文的主要目的是学习rn(δ1,δ2,c;q),并且为它给一个锋利的asymptotic公式。

  • 标签: 劳伦斯 正整数 渐近性质 渐近公式 护士
  • 简介:ANINTERSECTIONPROPERTYOFTHESIMPLERANDOMWALKSINZ ̄dZHOUXIANYIN(DepartmentofMathematics,BeijingNormalUniversity100875,China)Abst...

  • 标签: EFFECTIVE resistance SIMPLE RANDOM WALK INTERSECTION
  • 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:Wetackletheproblemofconstructing2DcentroidalVoronoitessellationswithconstraintsthroughanefficientandrobustconstructionofboundedVoronoidiagrams,thepseudo-dualoftheconstrainedDelaunaytriangulation.WeexploitthefactthatthecellsoftheboundedVoronoidiagramcanbeobtainedbyclippingtheordinaryonesagainsttheconstrainedDelaunayedges.Theclippingitselfisefficientlycomputedbyidentifyingforeachconstrainededgethe(connected)setoftriangleswhosedualVoronoiverticesarehiddenbytheconstraint.TheresultingconstructionisamenabletoLloydrelaxationsoastoobtainacentroidaltessellationwithconstraints.

  • 标签: VORONOI图 约束Delaunay三角网 二维 隐藏设置 三角形 约束边
  • 简介:Thispapergivesthedefinitionsandsomepropertiesofε-directionalderivateandε-subgradientsofcone-convexfunction.Fromthem,theoptimalityconditionsoflocalandglobaloptimalpointofunconstrainedcone-d.c.programmingaregained.Atlast,thedualitytheoremsofthisprogrammingarepresented.

  • 标签: ε-定向导出数 ε-子斜度 最优化条件 对偶定理 凸函数
  • 简介:Aseriesof2’-purineandpyrimidinederivativesof1’,4’-anhy-dro-2’-deoxy-D-arabitol(1)and1’,4’-anhydro-2’-deoxy-D-altritol(2)weresynthesizedregio-andstereo-selectivelyfromD-sorbitolthroughsomeconversioninhighyields.

  • 标签: STEREOSELECTIVE SYNTHESIS 2’-isonucleosides D-sorbitol
  • 简介:利用L-脯氨酸催化的5-氯水杨醛(1)与6-甲基-4-羟基吡喃酮(2)的缩合反应及硫酸铜催化下与1,3-二甲基-5-氨基吡唑(3)的串联反应,合成得到了10-氯-1,3-二甲基-5-(2-氧代丙基)色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(4)和10-氯-5-二乙氧基甲基-1,3-二甲基色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(5).化合物5的结构通过单晶X射线衍射法确定:晶体属于三斜晶系,空间群P-1;相对分子质量Mr=803.68;晶胞参数a=1.03160(10)nm,b=1.42900(13)nm,c=1.44268(15)nm;V=1.9448(3)nm~3;Z=2;晶胞密度Dc=1.372g/cm~3;吸收系数μ=0.228mm-1;单胞中电子的数目F(000)=840.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R=0.0681,wR=0.2051.在晶体结构中色烯环与吡啶环及吡唑环近似于共平面.

  • 标签: 吡唑并[3 4-b]吡啶 合成 晶体结构
  • 简介:The2Dplanegasflowunderheating(withnonentityboundarycondition)hasbeendiscussedbytheanalyticalapproachinthispaper.Theapproximateanalyticalsolutionshavebeenobtainedfortheflowpassingvariouskindsofheatsources.Solutionsdemonstratethethermaldisplacementphenomenaarestronglydependontheheatingintensity.

  • 标签: 热流体流 热位移 解析解
  • 简介:先建立除环上的矩阵范畴,并证明这个范畴是Abel范畴,然后利用范畴论中的结论给出除环上矩阵方程AXB=D有解的条件。

  • 标签: 除环 ABEL范畴 矩阵方程 充要条件
  • 简介:Inthispaper,anewproofofD’AlembertformulaforCauchyproblemsofwaveequationisproposed.AndsomeD’Alembert-typeformulasforCauchyproblemwithdiscontinuouscoefficientsonsemi-infiniteinitialboundaryvalueproblemareproposed.Basedonabovediscussion,thec(?)racteristicsmethodsforthedirectandinverseproblemsofthestresswaveequationforuniformlayeradelasticmediumareinvestigated.Theaimofthispaperistostressthesignificanceandapplicationofthecharacteristicsconceptandapproach.

  • 标签: proof DISCONTINUOUS INFINITE discussion FORMULAS inverse
  • 简介:Theaimofthispaperistogiveasimpleproofoftherestrictiontheoremforthemaximaloperatorsonthed-dimensionalEuclideanspaceRd,whosetheoremwasprovedbyCarro-Rodriguezin2012.Moreover,weshallgivesomeremarksoftherestrictiontheoremforthelinearandthemultilinearoperatorsbyCarro-RodriguezandRodriguez,too.

  • 标签: 限制定理 极大算子 多线性算子 简单证明 欧氏空间 德里
  • 简介:Cavitationisoneofthetroublesomeproblemsinrocketturbopumps,andsincemostofhigh-efficiencyrocketpropellantsarecryogenicfluids,socalled'thermodynamiceffect'becomesmoreevidentthaninwater.Inthepresentstudy.numericalandexperimentalstudyofliquidnitrogencavitationin2DLavalnozzlewascarriedout,sothattheinfluenceofthermodynamiceffectwasexamined.Itwasrevealedthattemperatureandcavitationhavestronginter-relationshipwitheachotherinthermo-sensitivecryogenicfluids.

  • 标签: 计算流体力学 CFD 喷流 两相流 空化 低温
  • 简介:Inthispaper,effectsonofsixtypeofresinsthedecolorizationofD-ribosezymoticfluidhavebeenstudiedforthefirsttime.TheresultsshowthatresinNKA-IIhasthebesteffect.thedecolorizationrageofD-ribosezymoticfluidis91%atvelocityof1.0BV/hrand25℃,theadsorptioncapacitycanreachupto5.7BV.Theeffectsofadsorptionconditionsaswellasconditionsofresinregenerationontheresindecolorizationcapabilitywerealsostudied.

  • 标签: D-核糖 脱色 树脂吸附
  • 简介:WereportonthefirstoperationsofthereconstructionfarmsfortheD0experiment.Datawerereadfromataperobotto50PC'srunningLinux,processed,spooledtoacentraldiskbufferformergingandthenwrittenbacktothetaperobot.Thefarmsarebeingusedsuccessfullytoreconstructthedataasitcomesin.Transferrateswelloverthe12.5MB/secneededforfulldatarateshavebeenachieved.

  • 标签: D0实验 探测器 软件开发