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500 个结果
  • 简介:小说芳香脂肪族(amide-imide)poly,在方面链在主要的链和氢氧根benzamide单位包含chiral单位的s从3,5-diamino-N-(4-hydroxyphenyl)的步生长聚合被获得了有不同chiral二酸氯化物(1a1e)的benzamide(2)。理论计算借助于计算化学方法被做叙述在反应下面的每二酸氯化物单体的稳定的符合构造和取向调节。这些聚合物被常规技术描绘。产生聚合物显示出好热稳定性。包括crystallinity,固有的粘性和词法特征的聚合物的另外的物理性质也被学习。

  • 标签: 纳米结构 光学活性 生产性能 世代 苯甲酰胺 羟基苯基
  • 简介:The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.

  • 标签: Duffing' s EQUATION SUBHARMONIC TRANSIENT PROCESS
  • 简介:InJulyof1987,theSamplingSurveyofChildren’sSituationwasconductedin9provincesautonomousregionsofChina.Astratifiedtwo--stageclustersamplingplanwasdesignedforthesurvey.Thepaperpresentsthemethodsofstratification,selectingn=2PSU’s(cities/counties)withunequalprobabilitieswithoutreplacementineachstratumandselectingresidents/villagecommitteeineachsampledcity/county.Allformulaeofestimatingpopulationcharacteristics(especiallypopulationtotalsandtheratiosoftwototals),andestimatingvariancesofthoseestimatorsaregiven.Finally,weanalysetheprecisionofthesurveypreliminarilyfromtheresultofdataprocessing.

  • 标签: selecting estimating SAMPLED FORMULAE STRATIFICATION Sampling
  • 简介:ThemainaimofthispaperistoprovideconvergenceanalysisofQuasi-WilsonnonconformingfiniteelementtoMaxwell'sequationsunderarbitraryquadrilateralmeshes.Theerrorestimatesarederived,whicharethesameasthoseforconformingelementsunderconventionalregularmeshes.

  • 标签: 误差估计 麦克斯韦方程式 任意四边形 非一致性元素
  • 简介:我们基于clocked传播门为一个布思编码器建议一个新式样计划断热的逻辑(CTGAL)。当时,在新式样,布思编码器的结构的复杂性被减少速度更多样地被改进。断热二是补充收益增殖率,乘法器,乘数蓄电池(MAC)而且一个图案基于CTGAL。计算机模拟结果显示设计电路让正确逻辑工作并且显著地与MAC的相比的更少的能源消耗基于互补金属氧化物半导体(互补金属氧化物半导体)逻辑。

  • 标签: 传输门绝热逻辑电路 乘法器-累加器 BOOTH算法 补码
  • 简介:ThispaperpresentsapropersplittingiterativemethodforcomparingthegeneralrestrictedlineareuqationsAx=b,x∈T(where,b∈AT,andTisanarbitrarybutfixedsubspaceofCm)andthegeneralizedinAT,SForthespecialcasewhenb∈ATanddim(T)=dim(AT),thissplittingiterativemethverseAT,ShodconvergestoAT,Sb(theuniquesolutionofthegeneralrestrictedsystemAx=bx∈T).

  • 标签: PROPER SPLITTING RESTRICTED linear equations the
  • 简介:ProfessorBeranektalkedaboutthesoundqualitiesofconcerthall.The58famousconcerthallsintheworldweregradedaccordingtothesubjectivecomparisonfromtheprofessionalmusiciansandmusiclovers.Sixmeasurableobjectiveparameterswereproposed.Therankingaccordingtotheseparameterswerepresented.

  • 标签:
  • 简介:Inthispaper,weusethedeformationmethodandG-equivarianttheorytoprovetheexistenceandmultiplicityofharmonicmapsfromanannulustotheunitsphereinR~3withsymmetricboundaryvalue.Inparticular,wecangetinfinitelymanyhomotopicallydifferentharmonicmapsiftheboundaryvalueisS~1-equivariantandnonconstant.

  • 标签: INFINITELY MULTIPLICITY harmonic proof regularity invariant
  • 简介:Inthispaper,anewclassofsolutionsofthevacuumEinstein'sfieldequationswithcosmologicalconstantisobtained.Thisclassofsolutionspossessesthenakedphysicalsingularity.ThenormoftheRiemanncurvaturetensorofthisclassofsolutionstakesinfinityatsomepointsandthesolutionsdonothaveanyeventhorizonaroundthesingularity.

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  • 简介:Inthispaper,theconceptofthes-doublydiagonallydominantmatricesisintroducedandthepropertiesofthesematricesarediscussed.Withthepropertiesofthes-doublydiagonallydominantmatricesandthepropertiesofcomparisonmatrices,someequivalentconditionsforH-matricesarepresented.TheseconditionsgeneralizeandimproveexistingresultsabouttheequivalentconditionsforH-matrices.Applicationsandexamplesusingthesenewequivalentconditionsarealsopresented,andanewinclusionregionofk-multipleeigenvaluesofmatricesisobtained.

  • 标签: H-矩阵 S-双对角占优矩阵 余角 高斯变换
  • 简介:Compositesofcarbonaerogelandgraphiteoxide(GO)weresynthesizedusingaself-assemblymethodbasedondispersiveforces.Theirsurfacewasmodifiedbytreatmentinhydrogensulfideat650and800℃.Thesamplesobtainedwerecharacterizedbyadsorptionofnitrogen,TA-MS,XPS,potentiometrictitration,andHRTEMandtestedascatalystsforoxygenreductionreactions(ORR)inanalkalinemedium.Thesynergisticeffectofthecomposite(electricalconductivity,porosityandsurfacechemistry)leadstoagoodORRcatalyticactivity.Theonsetpotentialforthecompositeofcarbonaerogelheatedat800℃isshiftedtoamorepositivevalueandthenumberofelectrontransferwas2e-atthepotential0.68VversusRHEanditincreasedto4e-withanincreaseinthenegativevaluesofthepotential.Anexcellenttolerancetomethanolcrossoverwasalsorecorded.

  • 标签: 石墨复合材料 还原催化剂 碳气凝胶 氧化 氧还原反应 掺杂
  • 简介:Becausemostpiezoelectricdeviceshaveinterfaceswithfluidinengineering,itisvaluabletostudythecoupledfieldbetweenfluidandpiezoelectricmedia.Asthefundamentalproblem,the3DGreen'sfunctionsforpointforcesandpointchargeloadedinthefluidandpiezoelectricbimaterialsarestudiedinthispaper.Basedonthe3Dgeneralsolutionsexpressedbyharmonicfunctions,weconstructedthesuitableharmonicfunctionswithundeterminedconstantsatfirst.Then,thecouplefieldinthefluidandpiezoelectricbimaterialscanbederivedbysubstitutionofharmonicfunctionsintogeneralsolutions.Theseconstantscanbeobtainedbyvirtueofthecompatibility,boundary,andequilibriumconditions.Atlast,thecharacteristicsoftheelectromechanicalcoupledfieldsareshownbynumericalresults.

  • 标签: 压电材料 流体 格林函数 三维 机电耦合场 GREEN函数
  • 简介:ThisarticleobtainsanexplicitexpressionoftheheatkernelsonH-typegroupsandthenfollowtheestimateofheatkernelstodeducetheHardy'suncertaintyprincipleonthenilpotentLiegroups.

  • 标签: 不确定性原理 类型分析 热核函数 数学
  • 简介:Inordertoimprovethecarsalesservice4Sshopmanagementlevel,improvetheeconomicandsocialbenefitsofenterprises,incentivesareusedtoencouragetheirown4sshops.Inthispaper,throughouttherelatedanalysisofthequarterlyandannualawardsincentiveprograminlarge-scaledomesticautomobileenterprises,entropymethodwithMATLABsoftwareisappliedtoestablishthedimensionalfitfunction.Inthedataprocessing,themultiplelinearregressionfunctionintoLingosoftwareisemployedtogetthebestsolution;andClanguageisusedtorunthescreeningdataprogramthroughtheconsistencytestprograminthesensitivityanderroranalysis.Firstofall,considerthecompanytomaximizeprofitsandmaximizetheamountofcomplaintsinthestoretomaintainalowtarget;intermsofstaff,weshouldconsiderprovidingmoreincentivesforemployees;inthecustomer,theoverallsatisfaction,serviceAttitude,vehiclecleanlinessbasedshouldbeimproved.Andtwoprogramsforthemonthlyprofitandexcessprofitsofprogressiveincentivesshouldalsobeimproved.

  • 标签: ENTROPY Weight Method RELATED INDICATORS GRAY
  • 简介:<正>LetMbeacompactminimalsurfaceinS3.Y.J.Hsuprovedthatif‖S‖2≤2(21/2π,thenMiseithertheequatorialsphereortheCliffordtorus,where5"isthesquareofthelengthofthesecondfundamentalformofM,‖·‖2denotestheL2-normonM.Inthispaper,wegeneralizeHsu’sresulttoanycompactsurfacesinS3withconstantmeancurvature.

  • 标签: COMPACT surface CONSTANT mean CURVATURE GLOBAL
  • 简介:ItisshownthatananomalyofthespectrumtakesplaceintheinterferencefieldwhenYoung'sdouble-slitinterferenceexperimentisilluminatedbyspatiallycoherentpolychromaticlight.Specifically,drasticspectralchanges(i.e.thespectralshiftsexhibitarapidtransition)occurinthevicinityofthedarkfringes.Thepotentialapplicationsofthisspectralanomalyarealsoconsidered.

  • 标签: 反常行为 杨氏双缝干涉实验 空间连续多色光 光谱转换
  • 简介:本文主要讨论意义更为一般的广义逆矩阵AT,s^(2)的若干性质及在解限制性线性方程组方面的应用.

  • 标签: 广义逆A T s^(2) 性质 应用