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500 个结果
  • 简介:针对当前尚无直接利用海图水深构建不规则三角网(triangulatedirregularnetwork,TIN)进行水下地形匹配定位的现状,提出了一种基于TIN模型的水下地形匹配定位算法。首先,在经典TERCOM(terraincontourmatching)算法的基础上,设计基于TIN模型的匹配搜索区的确定方法;然后,给出待匹配航迹点的水深值计算公式;最后,构建目标匹配定位的地形相关组合算子,实现匹配定位。实验结果表明:①本文所提算法可以用海图的原始水深直接构TIN模型作为匹配基准图进行匹配定位,且其定位精度可明显高于基于规则格网模型的经典TERC0M算法;②新方法可以有效的降低误匹配的发生;③提出的MMD+MSD组合匹配算子能够一定程度上克服水深系统误差对定位精度的影响。

  • 标签: 匹配定位算法 组合匹配 水下地形 不规则三角网 数字水深模型
  • 简介:介绍了TIN进行面模型构造的方法,对面模型构造过程中的三角剖分和模型优化问题进行了分析。以广泛采用的Delaunay三角网为例,设计了三维曲面模型的构造方法,并基于C++结合0PENGL开发了三维曲面构造软件。最终将软件应用于三维地形构造,对丘陵山地和盆地或高原边缘进行了模型构造,取得了的。

  • 标签: TIN 三维面模型 DELAUNAY
  • 简介:一、概述不规则三角网(TIN)是一种表示数字高程模型的方法。不规则三角网数字高程由连续的三角面组成,三角面的形状与大小取决于不规则分布的测点的位置和精度。不规则三角网与数字高程矩阵方法不同之处是随地形起伏变化的复杂性而改变采样点的密度和决定采样点的位置,因而它能够避免地形平坦时的数据冗余,又能按地形特征线如山脊线、山谷线、地形变化线等表示数字高程特征。

  • 标签: TIN模型 不规则三角网 数字高程模型 等高线 地形特征线 应用
  • 简介:一、引言数字高程模型(DEM)是进行3维空间数据处理,地形分析和进行三维视景仿真的核心数据。DEM常用TIN和GRID2种数据结构形式描述,其中,TIN由于具有可变的分辨率,精度高,能较好地表现不规则地貌的形态特征,因而具有非常广泛的用途。但一般情况下,地形本身的数据量很大,当需要实现对地形的多分辨率显示时,便需要对地形数据进行简化,以得到不同分辨率的地形模型。因此,如何在保持一定精度的前提下,对原数据模型进行简化,以减少数据量,消除数据冗余便成为人们关心的一个焦点,本文对该问题进行了研究,通过删除简化地形描述误差小于阈值的点,并对局部三角网进行Delaunay最优三角剖分,从而达到简化的目的,该算法能较好地保留地形特征点,使简化后的地形与原地形保持最大的相似性。最后,利用试验对本文算法进行了验证。

  • 标签: 数字高程模型 三维视景仿真 TIN 多分辨率显示 DELAUNAY 地形分析
  • 简介:EarlyoneJanuarymorningIsatinamodernDaewoocoachofYunnanExpressasitpulledoutofKunming'sLongDistanceBusStation.IwasheadingtothewarmthofsouthernYunnan,toGejiu,capitalofHonghePrefecture.

  • 标签: 云南 红河州 人文景观 历史文化 民族习俗
  • 简介:Afterformationsometinoredepositssufferedmoreorlesstransformingbylatergeologicalpro-ccsscs,sothattheyhaveshownthefeaturesofpolymetallo8enicepochs,polymetallogenic8tagcs,polymctal1izations,polygenicmatters,multifactorore-control8andpolmpetallogenictypesetc.andtheyhavetransformedintopo1ygeneticcompound

  • 标签:
  • 简介:Throughinterfacialpoly-condensationofR2SnCl2(R=Me,Bu)withvariousdiacids,diphenols(diols),diamines,amino-acids,hydroxyacids,urea,orthiourea,aseriesoforgano-tinpoly-esters,poly-ethers,poly-amines,poly-amine-esters,poly-ureas,poly-thioureaswereprepared,andcharacterisedaltogethertotalling100polymers,amongwhich91arepreviouslyunreported.ThesynthesizedpolymershaveapotentialasathermostabilizerinPVCproducts.

  • 标签: 有机金属聚合物 合成 锡聚合物 性质
  • 简介:Eightnovelcompoundshavebeensynthesizedandtheyaretwoseriesofmixedtri(butyl/cyclohexyl)tincarboxylates:BunCy3-nSnO2CR(n=1,2;R=n-C3H7,C6H5,4-ClC6H4,4-NO2C6H4).InadditiontothestudiesoftheirstructureswithIR,119Snand13CNMR,wetestedtheirfungicidal,insec-ticidalandacaricidalactivities.Thepercentageofinhibitiontotheaforementionedphytopathogenisabout80—100%at50ppminglasshouseand100%forT.Uriticaeat500ppm.Thosefindingsindicatethatthiskindofcompoundshavebothfungicidalandacaricidalactivitiesandmayhaveagoodprospectforapplications.

  • 标签: BUTYL alkyl CARBOXYL CARBONYL fragmentation coordinated
  • 简介:TheYinyanporphyrytindepositisablinddepositassociatedwithasmallgraniteporphyrystock.ThepetrologyandgeochemistryoftheYinyangraniteporphyrysuggestthatitisgeneticallyofthetransfor-mationtype,emplacedatthelatestageoffractionalcrystallizationwithinahigh-levelmagmachamber.Ore-formingfluidsarederivedpredominantlyfromthegraniticmagmaandtheyinteractwiththewallrocksintenselywhenfindingtheirwayupwardsthroughthegraniteporphyry.Fromthelowerpartoftheporphyryupwardsthefollowingalterationzonescanbedistinguished(a)slightlyalteredgraniteporphyry(withweakpotashfeldspathization),(b)protolithionite-quartzgreisenizationzone,(c)to-paz-quartzgreisenizationzone,(d)senicite-quartzsericitizationzone,and(e)silicificationzone(quartzcoreatthesurface).Tinmineralizationisrelatedtogreisenization,especiallytotopaz-quartzgreisenization.Rockandore-formingtemperaturesandoxygenfugacitiesareestimated,respectively.TherearesignificantdifferencesinmanyaspectsbetweentheYinyanporphyrytindepositandvolcan-ic-subvolcanicporphyrytindeposits.

  • 标签: 斑岩 锡矿床 地质构造 地球化学 广东
  • 简介:Titaniumnitride(TIN)filmsweredepositedonAISI304stainlesssteelsubstratesusinghollowcathodeplasmaphysicalvapordeposition(HC-PVD).TitaniumwasintroducedbyerodingtheTicathodenozzleandTiNwasformedinthepresenceofanitrogenplasmaexcitedbyradiofrequency(RF).Thesubstratebiasvoltagewasvariedfrom0to-300Vandtheuniformityinfilmthickness,surfaceroughness,crystalsize,microhardnessandwearresistanceforthefilmwithadiameterof20mmwasevaluated.Althoughthecentralzoneoftheplasmahadthehighestiondensity,thefilmthicknessdidnotvaryappreciablyacrossthesample.Theresultsfromatomicforcemicroscopy(AFM)revealedalowsurfaceroughnessdominatedbyanisland-likemorphologywithasimilarcrystalsizeontheentiresurface.Highermicrohardnesswasmeasuredatthecentralzoneofthesample.Thesampletreatedat-200Vhadexcellenttribologicalpropertiesanduniformity.

  • 标签: 空心阴极放电 氮化钛薄膜 硬度均匀性 物理气相沉积 表面粗糙度 制备
  • 简介:Bis(β-alkoxycarbonylalkyl)tindichlorideswereinterfacialcondensedwithorganicdithio-alcoholstogiveaseriesofneworgano-tinpolymers.Experimentalparameterswerediscussed.Thepolymerssynthesizedweretestedfortheireffectontheheat-stabilizationofPVCresins.Theresultsareofinterestinthisareaofapplication.

  • 标签: 合成 有机锡化合物 二(β-烷氧基羰烷基)锡多硫醚
  • 简介:Nuclearbindingenergies,chargeradiiandthechargedistributionsofeven-eventin(Sn)isotopesarecalculatedusingrelativisticmeanfieldtheory,andthetheoreticalresultsarefoundtobeinaccordancewiththeexperimentaldata.ThenuclearchargeformfactorsforSnisotopesarecalculatedusingthephase-shiftanalysismethod.ItisshownthattheminimaofthechargeformfactorsshiftupwardandinwardwithanincreaseintheneutronnumberoftheSnisotopes.

  • 标签: 电荷分布 同位素 相对论平均场理论 计算结果 形状因子
  • 简介:Thevacuumdiffusionbondingoftitaniumalloytotin-bronzehasbeenstudiedandthefeasibilityandappropriateprocessingparametershavebeeninvestigated.Themaximumtensilestrengthofthejointsis168MPa,andafirmjointisobtained.ThemicrostructureofdiffusionbondedjointhasbeenobservedbySEM.X-rayandEPMA,andthemainfactorsaffectingdiffusionbondinghavebeenanalyzed.TheintermetalliccompoundsTi2CuandTiCuwereformedneartheinterface.Thewidthandquantityoftheintermetalliccompoundincreaseswiththeincreaseofthebondingtime.Theformationoftheintermetalliccompoundsresultsinembrittlementofthejointandthepoorjointproperties.

  • 标签: 钛合金 锡青铜合金 扩散结合
  • 简介:摘要硬质TiC、TiN、Ti(CN)薄膜因具有相似的性质,故合称为TiN类薄膜。TiN类薄膜因具有高强度、高硬度、化学稳定性好、耐磨及防腐蚀等一系列优点,其涂层被广泛作用于机械工业中的刀具、模具等表面,成为具有巨大应用前景的涂层材料。TiN类陶瓷膜由于其独特的性能而成为当前材料表面研究热点之一。文章简要介绍了利用化学气相沉积(CVD)、物理气相沉积(PVD)、双辉技术及其它表面处理技术制备TiN类膜的研究进展,讨论了各种制备方法的工艺特点。

  • 标签: 表面技术 TiN类膜 制备工艺
  • 简介:Laserbeamweldingisanewtechniqueforthefoodcanmaking.Thisresearchstudiedtheweldingtechnologyandparametersforthetin-platecanandtheirinfluencesonweldingspeedandquality,investigatedthemicrostructureandpropertiesoftheweld,analyseddistributionoftinintheweldmetalandcarriedouttheflangingtestofthecanbody.Theresultsshowthatlaserweld-ingofthecanbodyischaracterizedbyhighweldingspeed,fineappearance,goodqualityandstableandreliableprocess.Thistechnologycanfulfillthere-quirementsofcanmaking.

  • 标签: laser WELDING CAN TIN PLATE
  • 简介:在这研究,听电影的二种类型被准备,一使用用多弧离子小块地(MAIP)的有一个在里面飞机S过滤器的过滤cathodic弧血浆(大页书写纸)技术,和其它,和两个在一样的参数下面扔了。质地,坚硬,粗糙,tribological和听电影的二种类型的电气化学的腐蚀行为的比较被给。FCAP技术获得的听电影被发现高度一致、光滑、macroparticle免费。听电影由有的大页书写纸扔了一(111)比较喜欢取向,当有时,在这些电影的质地都没由MAIP扔。在低负担下面,二种听涂层有很不同穿机制;有的大页书写纸的电影一更低与MAIP技术扔的听电影相比穿率和磨擦系数。大页书写纸的听电影的稠密、没有洞的结构能有效地在腐蚀测试期间从底层避免听电影的雪崩。

  • 标签: 非金属材料 微结构机械设备 TIN 过滤弧
  • 简介:ThesegregationandinteractionofREM,phosphorusandtinongrainboundariesofα-FewereinvestigatedbyAugerspectrometryandSEM.TheresultsshowthatREM,PandSntendtosegregateongrainboundariesofα-Fe.AddingREMintoFe-SnalloywithlowS,PcontentscouldsuppressthesegregationofSnongrainboundaries.ThesegregationofSnwoulddecreasewithincreasingofREM.InFe-Sn-PalloyPwouldsuppressthesegregationofSn.ThesegregationofPwouldbesuppressedbysegregationofREM.ThetrendofPsegre-gationdecreaseswithincreasingofREM.WithincreasingofREMthesegregationofSnatfirstisloweredbutthenfollowedwithanincreasing.AddingREMintoFe-SnandFe-Sn-Palloyscouldsuppressintercrystallinefractureofα-Featlowtemperatures.

  • 标签: RE P Sn Α-FE GRAIN BOUNDARY