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  • 简介:SIGN-REVERSALPROPERTYFORF-MATRICESANDN-MATRICESXUSong(GraduateSchool,ChinaAcademyofRailwaySciences,Beijing100081,China)Abstra...

  • 标签: N-matrices F-matrices linear complementarity problem
  • 简介:ANASYMPTOTICPROPERTYOFTHENUMBEROFSPANNINGTREESOFDOUBLEFIXEDSTEPLOOPNETWORKSYONGXUERONGANDZHANGFUJIAbstract.LetT(C(p,1,q))bet...

  • 标签: NETWORK
  • 简介:Inthispaper,wediscusstheconceptoffixedpointcurveforlinearinterpolationsofweaklyinwardcontractionsandestablishnecessaryconditionforanonexpansivemappingtohaveapproximatefixedpointproperty.

  • 标签: 不动点性质 收缩 曲线 定点 线性插值
  • 简介:OnCopositiveInthispapertheauthorwritesasimplecharacterizationforthebestcopositiveapproximationtoelementsofC(Q)byelementsoffinitedimensionalstrictChebyshevsubspacesofC(Q)inthecasewhenQisanycompactsubsetofrealnumbers.AttheendofthepapertheauthorappliesthisresultfordifferentclassesofQ.

  • 标签: STRICT CHEBYSHEV spaces best COPOSITIVE approximation
  • 简介:Thispaperreportsthesynthesisofaseriesofpolysiloxanesbearinglongsidechainmeltedatlowtemperature.Thedrug(LNG)releasingpropertiesofthesiciconerubberfilmscontainingthesepolyorganosiloxaneswerestudied.Thereleaseratesofthedrugincreaseasthetemperatureriseupabovethemeltingtemperatureofthesepolyorganosiloxanes.

  • 标签: 合成 药物释放性 聚硅氧烷 侧链 支链
  • 简介:Biomedicalsegmentedpolyetherurethane(SPEU)elastomersarecompositepoly-merswithmicrophaseseparationstructure.VariousattemptsofintroducingionicgroupsintoSPEUhavebeencarriedoutfortheimprovementoftheirbloodcompati-bilities.Weherereportthemechanicalandanticoagulantproperties.Twoseriesofsulfooctylpendantgroupscontainingsegmentedpolyetherurethaneswithwelldefinedfinestructurehavebeensynthesizedinourlab-oratory.ThesulfooctylgroupswereexactlylocatedatthehardsegmentswhentheSPEUswerepreparedfromthereactionofpolytetramethyleneglycol(PTMG)1000-4,4’diphenylmethanediisocyanate(MDI)oligomerswithN-sulfoalkyldiethanolamine

  • 标签: oratory SEGMENTED PTMG GLYCOL EXACTLY introducing
  • 简介:这篇文章为综合盖住一个方法环境地友好的多功能的金属(钙,镁)有antioxidationproperty.These的油酸盐detergents多功能的金属(钙,镁)有antioxidation性质的油酸盐detergents用油可溶的液体抗氧化剂被综合(PPIBP,PPIBTSTBP,并且PPIBPDA)作为反应功能的materials.These,油可溶的液体抗氧化剂有潜力在综合为申请被用作功能的材料其它种s

  • 标签: 合成洗涤剂 抗氧化作用 多功能 金属 油酸 环保
  • 简介:热处理完成,包括答案处理(圣)和老化处理(在),在优先的奥氏体谷物(PAG)上尺寸,微观结构和变硬的猛冲的机械性质妈发怒不锈钢被调查。结果显示在PAG之间的关系在圣下面并且以条件缩放并且让步力量(sigma_y)服从theHall-Petch关系。而且,在在为1的1050degC的圣以后,h+cryogenic对待(CT)在为在为4h的535degC的8h+AT的-70degC,测试的钢分别地在1900MPa和1750MPa上显示出它的最终的张力的力量(sigma_b)和sigma_y。

  • 标签: 马氏体时效型不锈钢 微观结构 沉淀硬化 热处理 结晶粒度 机械性能
  • 简介:Silica-boundmercaptoselenaether-containingsilsesquioxaneanditsplat-inumorrhodiumcomplexweresynthesizedfromγ-(2,3-epithiopropyl)propyltrimethoxysi-laneviaring-openingreactionwithbis(2-hydroxyethyl)sclenide,followedbyhydrolysisandimmobilizationonfumedsilica,andthenreactingwithpotassiumchloroplatiniteorrhodiumchlorideinacetoneundernitrogenatmosphere.Itwasfoundthattwonoblemetalcomplexescancatalyzethehydrosilylationofolefinswithtriethoxysilaneeffectively.Theinfluencesoftemperature,theamountofcomplexused,thenatureofolefinoncatalyticactivitywereinvestigated.

  • 标签: POLYMER-SUPPORTED CATALYST HYDROSILYLATION CATALYST PLATINUM RHODIUM
  • 简介:Inthispaperthedesignproblemofperfect-reconstructioncosine-modulatedQMFbankshasbeenformulatedasaquadratic-constrainedleast-squares(QCLS)minimizationprobleminwhichallconstrainedmatricesoftheQCLSoptimizationproblemaresymmetricandpositivedefinite.AcostfunctionwhichisaconvexfunctionofdesiredprototypefiltercoefficientsisconstructedsothatthiskindofQCLSoptimizationproblemscanbeefficientlysolved.Soaglobalminimizerofthisproblemcanbeeasilyobtained.Resultsoftwodesignexamplesarepresentedtosupportthederivationsandanalyses.

  • 标签: Quadratic-constrained least-squares(QCLS) Cosine-modulated QMF BANKS Global
  • 简介:Cloudmicrophysicalpropertyretrievalsfromtheactivemicrowaveinstrumentonasatelliterequiretheclouddropletsizedistributionobtainedfromaircraftobservationsasaprioridataintheiterationprocedure.Thecloudlognormalsizedistributionsderivedfrom12flightsoverBeijing,China,in2008–09werecharacterizedtoevaluateandimproveregionalCloudSatcloudwatercontentretrievals.Wepresentthedistributionparametersofstratiformclouddroplet(diameter<500μmand<1500μm)anddiscusstheeffectoflargeparticlesondistributionparameterfitting.Basedonthreeretrievalschemeswithdifferentlognormalsizedistributionparameters,theverticaldistributionofcloudliquidandicewatercontentwerederivedandthencomparedwiththeaircraftobservations.Theresultsshowedthattheliquidwatercontent(LWC)retrievalsfromlargeparticlesizedistributionsweremoreconsistentwiththeverticaldistributionofcloudwatercontentprofilesderivedfrominsitudataon25September2006.WethenappliedtwoschemeswithdifferentaprioridataderivedfromflightdatatoCloudSatoverpassesinnorthernChinaduringApril–Octoberin2008and2009.TheCloudSatcloudwaterpath(CWP)retrievalswerecomparedwithModerateResolutionImagingSpectroradiometer(MODIS)liquidwaterpath(LWP)data.TheresultsindicatedthatconsideringaprioridataincludinglargeparticlesizeinformationcansignificantlyimprovetheconsistencybetweentheCloudSatCWPandMODISCWP.Theseresultsstronglysuggestthatitisnecessarytoconsiderparticleswithdiametersgreaterthan50μminCloudSatLWCretrievals.

  • 标签: 飞机观测 反演 物理属性 北京 中分辨率成像光谱仪 MODIS
  • 简介:Basedonthemethodofartificialneuralnetwork,anewapproachhasbeendevisedtopredictthemechanicalpropertyofE4303electrode.Theoutlinedpredicationmodelfordeterminingthemechanicalpropertyofelectrodewasbuiltupontheproductiondata.Theresearchleveragesabackpropagationalgorithmastheneuralnetwork'slearningrule.Theresultindicatesthattherearepositivecorrelationsbetweenthepredictedresultsandthepracticalproductiondata.Hence,usingtheneuralnetwork,predicationofelectrodepropertycanberealized.Forthefirsttime,thisresearchprovidesamorescientificmethodfordesigningelectrode.

  • 标签: 人工神经网络 电极设计 性质预测 焊接自动化