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135 个结果
  • 简介:<正>Teenagershavebeenofanewshapethesedays.Theyareabout20poundsheavierthanteenagerswere60yearsago.Theyareaboutfourinchestaller,too.ThesefactscomefromJ.M.Tanner,aprofessorinEngland.

  • 标签: PROFESSOR FACTS Tanner SHAPE TEENAGERS TODAY
  • 简介:“Ittakesanentirevillagetoraiseachild.”That'sanoldproverbthatisbeingusedmoreandmoreoftenthesedays.Today,moreandmoreschoolsarereachingouttoinvolveparents,communitymembersandbusinessestohelpshapeachild'sfuture.

  • 标签: 高中 英语 写作指导 范文
  • 简介:本节课的设计关注学生的情感、语言感受,从学生已有的认知水平出发,培养学生在学习中乐于参与、积极合作、主动表达,力求发挥学生的主体地位,重视学生对知识内化后的语言输出能力的培养,让学生在愉快的氛围中享受英语学习的乐趣,体验学习成功的快乐,初步形成对英语的感知能力和良好的学习习惯及策略。

  • 标签: 语言输出能力 情景对话 词汇积累 句型渗透
  • 简介:Wedevelopadatadrivenmethod(probabilitymodel)toconstructacompositeshapedescriptorbycombiningapairofscale-basedshapedescriptors.Theselectionofapairofscale-basedshapedescriptorsismodeledasthecomputationoftheunionoftwoevents,i.e.,retrievingsimilarshapesbyusingasinglescale-basedshapedescriptor.Thepairofscale-basedshapedescriptorswiththehighestprobabilityformsthecompositeshapedescriptor.Givenashapedatabase,thecompositeshapedescriptorsfortheshapesconstituteaplanarpointset.AVoR-Treeoftheplanarpointsetisthenusedasanindexingstructureforefficientqueryoperation.Experimentsandcomparisonsshowtheeffectivenessandefficiencyoftheproposedcompositeshapedescriptor.

  • 标签: SHAPE DESCRIPTOR SHAPE RETRIEVAL SHAPE analysis
  • 简介:InCAD/CAM,meshratherthansmoothsurfaceisonlyneededsometimes.Amesh-generatingmethodfrompermanenceprincipleofCoonspatchisdeveloped.Anewmeshpointisdefinedthroughlocalsmallsubpatchandallmeshpointsarecomputedbyalinearsystemwithspecialsymmetricblocktridiagonalcoefficientmatrix.Bysimplification,thedeterminantofcoefficientmatrixisdeterminedbydeterminantsofsubmatrices.Conditionofexistenceofsolutionisgiven.Whethercoefficientmatrixissingularcanbejudgedbyasimplepolynomialfunctionwiththeeigenvalueofsubmatrixasvariable.Numericalexamplesdemonstratetheeffectsofshapeparameters.

  • 标签: 形状参数 生成网格 系数矩阵 多项式函数 表面光滑 线性系统
  • 简介:Molecularmaterialsarethoseconstitutedbyweakintermolecularinteractions(e.g.,interac-tion,hydrogenbonding,andvanderWaalsforce)betweenindividualcomponentmolecules.Whileconventionalsemiconductingmaterialsareconstitutedbystrongintermolecularinteractions(e.g.,covalentbonding,metallicbonding,and

  • 标签: 英语 阅读 理解 复合材料
  • 简介:高贵金属性的nanostructures展览专辑光性质源于表面电浆子的刺激。在各种各样的金属性的nanostructures之中,因为他们的唯一、吸引人的形状依赖者plasmonic性质,nanorods吸引了特别注意。Nanorods能支持横向、纵的电浆子模式,后者一强烈取决于nanorod的方面比率。这些模式能习惯性地被调节从对可见在红外线附近光谱区域。尽管nanorods广泛地被调查了,有很少研究,奉献给从nanorod形状背离的nanostructures。这评论在二种新奇quasi-one-dimensional银nanostructures,nanorice和nanocarrot的开发提供最近的进步的概述,包括他们在察觉到应用程序的plasmonic的综合体,水晶的描述,plasmonic性质分析,和性能。

  • 标签: 光学性质 纳米结构 纳米棒 形状 金属纳米材料 表面等离子体
  • 简介:Weestablishtheconceptofshapesoffunctionsbyusingpartialdifferentialinequalites.Ourdefinitionaboutshapesincludessomeusualshapessuchasconvex,subharmonic,etc.,andgivesmanynewshapesoffunctions.Themainresultsshowthattheshapepreservingapproxi-mationhascloserelationtotheshapepreservingextension.Oneofourmainresultsshowsthatiff∈C(Ω)hassomeshapedefinedbyourdefinition,thenfcanbeuniformlyapproximatedbypolynomialsPn∈pn(n∈N)whichhavethesameshapeinΩ,andthedegreeoftheap-proximationisCω(f,n-β)withconstantsC,β>0.

  • 标签: PRESERVING CONVEX UNIFORMLY CONSTANTS whenever applying
  • 简介:Confinementcaninduceunusualbehaviorsofwater.Inspiredbythefabricationofcarbonnanotubeswithnoneircularcrosssections,weperformedmoleculardynamicssimulationstoinvestigatethemo-bilitiesofwaterconfinedincarbonnanochannelswithcircular,square,andequilateraltriangularcrosssectionsoveravarietyofdimensions.Wefindthatwaterexhibitsdisparatemobilitiesacrossdifferenttypesofchannelsbelow0.796nm^2.Notably,comparedwiththeothertwochannels,waterinequi-lateraltriangularchannelsdisplaysthegreatestmobilities.Moreover,at0.425nm^2,differentorderedstructuresarefoundinthethreechannels,andwaterinsidethesquarechannelexhibitsanextremelylowInobility.Itisalsofoundthatabove0.796nm^2,themobilitiesalongthetubeaxisofwatercon-vergetothatofthebulk.Thesephenomenaareunderstoodbyanalyzingthestructure,dynamics,andhydrogenbondingofwater.Ourworkexploresthemobilitiesofwateracrossnoncireularcarbonnanoehannels,whichmayexpandtheprospectofnoneireularnanochannelsinscientificstudiesandpracticalapplications,suchasdesalinationanddrugdelivery.

  • 标签: MOLECULAR DYNAMICS simulations mobility noncircular nanochanncl
  • 简介:Fortheimageofasmoothsurfaceobjectfullycontainedwithinthefieldofviewandilluminatedinandarbitrarydirection,thispaperdiscussestheexistenceanduniquenessotheconditionsforsolvingashape-from-shadingproblemundertheconditionsthattheFourierseriesexpansionoftheimageintensitycontainsonlyzeroandfirstordertermsinapolarcoordinatesystem.Threetheoremsareestablished,onefortheexistenceandtwofortheuniquenessofz-axissymmetricshapefromshading.

  • 标签: 计算机显象 存在性 唯一性 形状阴影
  • 简介:当今,学生的成长和社会息息相关,孩子的成才离不开全社会的共同努力。假如你是某英文报社记者,根据下表内容,请以“Let’sWorkTogethertoShapeFuture”为题,写篇短文,呼吁全社会积极参与学校教育。

  • 标签: 高中 英语 学生习作 评析
  • 简介:Anorthorhombicpolycrystalisanorthorhombicaggregateoftinycrystallites.Inthispaper,westudytheeffectofthecrystallinemeanshapeontheconstitutiverelationoftheorthorhombicpolycrystal.Thecrystallinemeanshapeandthecrystallineorientationarrangementaredescribedbythecrystallineshapefunction(CSF)andtheorientationdistributionfunction(ODF),respectively.TheCSFandtheODFareexpandedasaninfiniteseriesintermsoftheWignerD-functions.TheexpandedcoefficientsoftheCSFandtheODFarecalledtheshapecoefficientssm0landthetexturecoefficientscmnlrespectively.AssumingthatCeffintheconstitutiverelationdependsontheshapecoefficientssm0landthetexturecoefficientscmnl,bytheprincipleofmaterialframe-indifferencewederiveananalyticalexpressionforCeffuptotermslinearinsm0landcmnl,andtheexpressionwouldbeapplicabletothepolycrystalwhosetextureisweakandwhosecrystallinemeanshapehasweakanisotropy.Ceffcontainssixunspecifiedmaterialconstants(λ,μ,c,s1,s2,s3),fiveshapecoefficients(s020,s220,s400,s420,s440),andthreetexturecoefficients(c400,c420,c440).Theresultsbasedontheperturbationapproachareusedtodeterminethefivematerialconstantsapproximately.Wealsofindthattheshapecoefficientss2m0ands4m0areallzeroifthecrystallinemeanshapeisacuboid.Someexamplesaregiventocompareourcomputationalresults.

  • 标签: 正斜方多晶体 形状系数 晶系 晶体力学
  • 简介:AGeometricRepresentationSchemeSuitableforShapeOptimizationWangXuelinandZhouJiCADCenter,HuazhongUniversityofScienceandTechnolo...

  • 标签: SHAPE optimization NURBS CURVE FINITE ELEMENT
  • 简介:AlayeredsimulationmodelwithstairstepcontourisbuiltfromAutoCADthroughextrudingeachsuccessivesectioncontourhavingbeencompensatedindimensionstomeettheapplicationrequirementsoftheRPpart.InsuchawaytheshapeandsizetoleranceoftheRPproductcouldbeverifiedbeforehandpromptlyandprecisely.

  • 标签: OBJECTARX 快速原型 形状 AUTOCAD 仿真 模拟模型
  • 简介:Alotof3Dshapedescriptorsfor3Dshaperetrievalhavebeenpresentedsofar.Thispaperproposesanewmechanism,whichemploysseveralexistingglobalandlocal3Dshapedescriptorsasinput.Withthesparsetheory,somedescriptorswhichplaythemostimportantroleinmeasuringsimilaritybetweenquerymodelandthemodelinthedatasetareselectedautomaticallyandanaffinitymatrixisconstructed.Spectralclusteringmethodcanbeimplementedtothisaffinitymatrix.Spectralembeddingofthisaffinitymatrixcanbeappliedtoretrieval,whichintegratingalmostalltheadvantagesofselecteddescriptors.Inordertoverifytheperformanceofourapproach,weperformexperimentalcomparisonsonPrincetonShapeBenchmarkdatabase.Testresultsshowthatourmethodisapose-oblivious,efficientandrobustnessmethodforeithercompleteorincompletemodels.

  • 标签: 形状检索 形状匹配 特征描述 查询模型 形状描述 相似性测量