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15 个结果
  • 简介:Polyamide(PA6)andpolycarbonate(PC)werepreparedbyaBrabendermixer(PLV-151)at240℃with30rpmfordurationof8and6minutesrespectively.Theepoxyresin(E)additioncanleadtosubstantialmicrostructuralchangesinthePA6/PCblends.Scanningelectronmicroscope(SEM)wasusedtoobservethemixturescharacterizedbythedomainsofclearlysegregatedhomophasesandvoidsbetweenthetwopolymers.PA6/PCofpolyamide6andpolycarbonatewithepoxyresinadditionunderthecompositionratioof20/80,20/80/1,40/60/1and40/60,weretestedtoverifythekeyroleofepoxyinpromotingthecompatibilityofPA6withPCduringblending.

  • 标签: 饱和 聚酰胺PA6 聚碳酸脂PC SEM
  • 简介:Duringtheevolvementofarchitecture,theresearchonarchitecturalformandstructureaswellasdifferentwaystoexpressandrealizearchitecturalthoughtsisconstantlythefocusofmanyarchitects,Thispaperillustratesthemutualinfluenceofthewaysofexpressionanddesignofarchitecturetopeople'sunderstandingofthemeaningofarchitecturethroughoutthehistoryoftheireffortsandexploration.thepaperalsodiscussestheextensiveusageofvirtual-realithapproachthroughcomputertechnology,Itpointsoutthatthetraditionalarchitecturalstandpointwillundergobreakthroughbytheemergenceofnewexpressionanddesignmethod.Inthisway,people'sunderstandingofarchitecturewillbemoreprofoundandlasting.

  • 标签: 建设设计 CAD 虚拟现实 建筑结构 计算机辅助设计
  • 简介:Inrecentyearswehavewitnessedalargeinterestinsurfacedeformationtechniques.Thishasbeenareactionthatcanbeattributedtotheabilitytodeveloptechniqueswhicharedetail-preserving.Spacedeformationtechniques,ontheotherhand,receivedlessattention,butneverthelesstheyhavemanyadvantagesoversurface-basedtechniques.Thispaperexploresthepotentialofthesetwoapproachestodeformationanddiscussestheopportunitiesthatthefusionofthetwomayleadto.

  • 标签: 空间变形 网格编辑 数字表面 表面变形
  • 简介:Twosetsarecloseiftheirsymmetricdifferenceisasparseset.ItisshownthatNP-hardsetsarenotC=P-closeunlessNPC=P.Thisimprovesthepreviousresultandhasimplicationinquantumcomputation.

  • 标签: 集合论 NP硬集 量子计算
  • 简介:BymeansofdirectanalysisoftheconnectionbetweenLoopsubdivisionsurfaceanditscontrolmeshandthecomputationofthebasisfunctions,weobtainaboundonthedistancebetweenLoopsubdivisionsurfacepatchanditscontrolmesh.Theboundcanbeusedtocomputethenumbersofsubdivisionforagiventolerance.Finally,twoexamplesarelistedinthispapertodemonstratetheapplicationsofthebound.

  • 标签: LOOP细分曲面 距离约束 控制网 曲面片 计算 绑定
  • 简介:Thispapergivesamethodofquantifyingsmallvisualdifferencesbetween3Dmeshmodelswithconformingtopology,basedonthetheoryofstrainfields.Strainfieldisageometricquantityinelasticitywhichisusedtodescribethedeformationofelastomer.Inthispaperweconsiderthe3Dmodelsasobjectswithelasticity.Thefurtherdemonstrationsareprovided:thefirstisintendedtogivethereaderavisualimpressionofhowourmeasureworksinpractice;andthesecondistogivereadersavisualimpressionofhowourmeasureworksinevaluatingfilteralgorithms.Ourexperimentsshowthatourdifferenceestimatesarewellcorrelatedwithhumanperceptionofdifferences.Thisworkhasapplicationsintheevaluationof3Dmeshwatermarking,3Dmeshcompressionreconstruction,and3Dmeshfiltering.

  • 标签: 三维网眼模型 视觉差别 网眼比较 感知 疲劳领域
  • 简介:AimingatthegeometricalfeaturesofdifferentcontainmentrelationshipsinRapidPrototyping(RP),ageneralmethodofachievingtheRPlayer’scuspdistributionofthepositive,negativeandmixedtoleranceisproposedtomeetthepart’sdifferentapplications.TheprocedureisexecutedbyprojectingthecurrentandthenextsectionoftheCADmodelontoahorizontalplane,computingtheunionandtheintersectionofthesectionstogettheouterandtheinnerboundary,andthenblendingtheboundariesusingarotaryvectorthroughaproperinnerpointintheintersectiontoachievethecurrentlayer’sscanningcontour.Themethodcanrealizethelayer’scuspdistributionofthemixedtolerancewithunequalcuspheight,expandingtheconnotationofthemixedtolerance.

  • 标签: CAD模型 原型零件 混合性 快速成形 几何特征 旋转矢量
  • 简介:由混乱节点组成的各种各样的典型复杂动态网络的稳定性质理论上被调查;数字地详细模仿了。如此的卡住的网络的一些本地稳定性性质被导出;有效稳定性区域基于特征值分析被估计。网络被给解释不太本地的控制器为什么显著地被明确地卡住需要的这的数字模拟策划,它在没有规模的网络卡住最高度连接的节点,与由随机卡住要求了比计划。另外,为什么为控制随机图的网络的二个计划之间没有重要差别,被解释;小世界的网络。

  • 标签: 混沌复杂动态网络 连接控制 随机控制 洛伦茨理论
  • 简介:Theharmonicdriveisakindofgeartransmissionthatuseswavegeneratortoproducecontrollablesoftroundelasticdeformationandengageswithrigidgeartotransmitmotionandpower.Theloaddistributiononthesurfaceoftheflexiblegearandwavegeneratorisanimportantparameterofstudyingthedeformationofflexiblegearandflexiblebearingoutsidethewavegeneratorandisalsoanecessaryconditionforstudyingthefatiguedamageofflexiblegearunderalternatingload.Inthispaper,a3Dmodelof32-type80:1harmonicdriveisbuild.BasedonthegeneralizedHookelaw,ahypothesisofloaddistributionwhichisprovedtobevaliditybyusingfiniteelementsimulationisproposedontheinterfaceofflexiblegearandwavegenerator.Onthisbase,themathematicmodelandthequantitativecalculationformulaoftheloaddistributiononthesurfaceoftheflexiblegearandwavegeneratorareproposedwhichprovideabasisforthedynamicanalysisandthefatiguedamageofharmonicgeardrive.

  • 标签: 谐波齿轮传动 波发生器 柔性轴承 谐波传动 载荷谱 广义虎克定律
  • 简介:为车辆适应巡航控制(ACC)系统,切换的性能在之间扼杀并且刹车决定开车舒适,燃料消费和车辆的服务生活机械部件。在这份报纸,有最佳的切换控制在之间的一个ACC算法扼杀并且刹车在模型被设计预兆的控制(MPC)框架。由介绍二进制整数变量,动力学扼杀并且刹车集成于为控制器设计的一模型表情。然后,ACC算法被设计满足不仅安全汽车列在后面,而且最佳的切换在之间扼杀并且刹车,它导致二次的编程由嵌套的二环的方法解决了的一个在网上混合的整数。模拟结果证明建议ACC算法满足安全汽车列在后面的要求,由执行更光滑的回答超过传统的算法,减少切换的时间在之间扼杀并且刹车,并且因此显著地改进开车舒适和燃料效率。

  • 标签: 自适应巡航控制系统 切换时间 刹车 油门 设计 混合整数二次规划
  • 简介:Inthispaper,thesmoothconnectionbetweentwoB-splinesurfacesisdiscussed.First,abriefproofofsomesimplesufficientconditionsofG~0andG~1continuityisgiven.Onthisbasis,anovelmethodforG~0orG~1connectionbetweentwoadjacentB-splinesurfacesispresented.Areparameterizationstepisfirstlytakenforoneofthesurfacessuchthattheyhavethesameparameterizationinvdirection,then,adjusttheirboundarycontrolverticestomakethemG~0orG~1connected.TheG~1connectionparameterisdeterminedbyanoptimizationproblem.Comparedwiththeexistedmethods,ourmethodissimpleandeasytobeusedinpractice.

  • 标签: B样条曲面 重新参数化 平滑连接 边界控制顶点 充分条件 优化问题