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简介：该型测量组合导航系统是在装船使用４年取得较好效果的情况下，于１９９３年２月通过部级技术鉴定，本文概要介绍了主要功能、技术途径、硬件设计特点、软件设计概况及数据处理技术，并综述了海上试验与试用情况等技术资料。

简介：Synchronousgammaoscillationsarebelievedtoplayaprominentroleintheinformationprocessingofbiologicalneuralsystems.Experimentalobservationshavefoundthatthefrequencyandpowerofgammaoscillationsintheprimaryvisualcortex(V1zone)areregulatedbytheilluminationcontrastofvisualstimulus.However,theunderlyingmechanismofhowthesynchronousoscillationsdependontheilluminationcontrasthasnotbeenwellexplained.Weproposealocalexcitatory/inhibitory(E/I)neuronalnetworkofintegrate-and-fire(IAF)neuronswiththedifference-of-Gaussians(DOG)receptivefieldtounveilthismechanism.Simulationresultsdemonstratethatthehighertheilluminationcontrast,thehigherthefrequencyofgammaoscillations.Thepowerofgammaoscillationsalsoincreaseswiththeincreaseofilluminationcontrast.Theseresultsareconsistentwiththeexperimentalfindings.

简介：TheconstitutiveequationforasemiconcentratedfibresuspensionintheOldroyd-Bfluidhasbeenderivedfromastatisticalmodelofsuchasuspensionbyemployingthemoleculartheoryforpolymericliquids.Tocircumventtheoreticaldifficultiesinviscoelasticfluidmechanics,severalsimplifiedmodelsareusedtoaccountfortheinteractionsoffibresandpolymermolecules.Someofmaterialfunctionsarecalculatedintermsoftheconstitutiveequation.

简介：ThispaperestablishesthevelocityfieldandtheadequateshearstresscorrespondingtothemotionofanOldroyd-BfluidbetweentwoinfinitecoaxialcircularcylindersbymeansoffiniteHankeltransforms.Theflowofthefluidisproducedbytheinnercylinderwhichappliesatime-dependentlongitudinalshearstresstothefluid.Theexactanalyticalsolutions,presentedinseriesformintermsofBesselfunctions,satisfyallimposedinitialandboundaryconditions.ThegeneralsolutionscanbeeasilyspecializedtogivesimilarsolutionsforMaxwell,secondgradeandNewtonianfluidsperformingthesamemotion.Finally,somecharacteristicsofthemotionaswellastheinfluenceofthematerialparametersonthebehaviorofthefluidmotionaregraphicallyillustrated.

简介：TheintrinsicphysicalrelationshipofvorticitybetweenmodesAandBinthethree-dimensionalwaketransitionisinvestigated.Directnumericalsimulationsfortheflowpastasquare-sectioncylinderarecarriedoutatReynoldsnumbersof180and250,associatedwithmodesAandB,respectively.Basedontheanalysisofspacialdistributionsofvorticityinthenearwake,characteristicsoftheverticalvorticityinmodesAandBareidentified.Moreover,therelationshipofthreevorticitycomponentswithspecificsignsissummarizedintotwosignlaws,asintrinsicphysicalrelationshipsbetweentwoinstabilitymodes.Bythetheoryofvortex-inducedvortex,suchtwosignlawsconfirmthattherearetwoandonlytwokindsofvortex-sheddingpatternsinthenearwake,justcorrespondingtomodesAandB.Inbrief,alongthefreestreamdirection,modeAcanbedescribedbytheparallelsheddingverticalvorticeswiththesamesign,whilemodeBisdescribedbytheparallelsheddingstreamwisevorticeswiththesamesign.Finally,itisfoundoutthatthe-typevortexisabasickindofvortexstructureinbothmodesAandB.

简介：ＡＳＵＰＰＬＥＭＥＮＴＡＲＹＳＴＵＤＹＯＦＡＮＩＳＯＴＲＯＰＩＣＰＬＡＳＴＩＣＦＩＥＬＤＳＡＴＡＲＡＰＩＤＬＹＰＲＯＰＡＧＡＴＩＮＧＰＬＡＮＥ－ＳＴＲＥＳＳＣＲＡＣＫ－ＴＩＰ（Ｉ）ＬｉｎＢａｉｓｏｎｇ（林拜松）（ＲｅｃｅｉｖｅｄＪｕｌｙ１５．１９９４...

简介：Inliterature,nonlineartravelingwavesinelasticcircularrodshaveonlybeenstudiedbasedonsinglepartialdifferentialequation(pde)models,andhereweconsidersuchaproblembyusingamoreaccuratecoupled-pdemodel.WederivetheHamiltonianfromthemodelequationsforthelongfinite-amplitudewaveapproximation,analyzehowthenumberofsingularpointsofthesystemchangeswiththeparameters,andstudythefeaturesofthesesingularpointsqualitatively.Variousphysicallyacceptablenonlineartravelingwavesarealsodiscussed,andcorrespondingexamplesaregiven.Inparticular,wefindthatcertainwaves,whichcannotbecourltedbythesingle-equationmodel,canarise.

简介：有沿着一张拉长的表的混合传送对流的非牛顿的液体的不可压缩的流动被分析。热转移现象通过热放射被讨论。融化的热转移和热产生/吸收的效果也被拿。合适的转变被利用达到非线性的平常的微分表情。会聚的系列答案被介绍。液体流动，温度，和表面热转移率图形地被检验。当时，松驰时间什么时候增加，被观察速度减少当延迟时间是不变的时，增加。当放射参数增加时，结果也表明温度分发减少。

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简介：文章详细讨论了两类非对称涡流动诱发的模型摇滚运动．第1类是针对旋成体机身组合体模型，其摇滚运动是由前体非对称涡流动诱发的，运功形态呈现不确定性，由模型头尖部的扰动触发形成．文章提出了快速旋转头尖部扰动的控制技术，以抑制该类模型的大攻角摇滚运动．第2类是针对非常规机身的组合体模型，其摇滚运动的主控流动是非常规机身和机翼的前缘分离涡流动，这些流动是由组合体模型的边界条件确定的，从而运动形态具有很好的确定性．所以，这类模型的自由摇滚运动必须通过改变边界条件来改变诱发摇滚运动的流动，以达到抑制模型自由摇滚运动的目的．最后，文章还讨论了这类运动是由非对称的机翼涡涡强主控的．

简介：预测类Apollo返回舱外形在高焓来流下的气动热特性,研究网格Reynolds数、壁面温度、多种化学反应模型以及限制器对预测热流的影响.采用ESI-CFD-FASTRAN软件作为数值模拟平台,使用基于温度梯度及分子扩散效应的热流模型;空间离散采用Roe-FDS格式,时间推进采用点隐式;采用等温壁面条件.数值计算表明:(1)热流在返回舱头部驻点处达到一个极值,沿着壁面热流不断下降,经过返回舱肩部热流有突越上升;(2)满足网格Reynolds数小于10的网格获得的热流较为准确;(3)使用Gupta模型计算得到的热流与Park85模型得到的类似,但是获得的热流分布类似;(4)采用湍流模型获得的头部肩部热流结果与层流结果相同;(5)二阶min-mod限制器实现了高阶格式,其计算得到的热流结果在肩部略高,但是整体分布略低于不带限制器的格式.因此,在计算中采用满足网格Reynolds数壁面网格,采用带限制器的高阶格式计算获得的热流分布更加准确;由于头部热流主要贡献并非来源于湍流,因此对于肩部热流采用层流模型足够准确.

简介：在laminar的非线性的传送对流的效果三维的Oldroyd-B液体流动被探讨。热转移现象被考虑非线性的热放射和热产生/吸收探索。边界层假设被考虑管理流动分析的数学模型。一些合适的类似变量被介绍把部分微分方程转变成平常的微分系统。有射击方法的Runge-Kutta-Fehlberg第四顺序、第五顺序的技术被用来获得无尺寸的速度和温度的答案。液体速度和温度上的各种各样的物理参数的效果被阴谋并且检验。比较与准确并且homotopy不安答案被做为粘滞液体大小写，和一根优秀火柴被注意。墙的数字价值砍在墙的压力和热转移率被公布并且调查。在德卜拉数字的价值的改进在液体速度上显示出反向的行为。当非线性的传送对流参数增加时，结果证明温度和热边界层被减少。Nusselt数字的价值比处于线性放射状况的那些处于非线性的放射状况是更高的。

简介：本文针对陀螺随机漂移的弱非线性和非平稳性,提出了一种多项式NAR模型及其辨识方法。对陀螺随机漂移测试数据的仿真表明,该模型能很好地用来预报陀螺随机漂移。

简介：Globallook-uptablestrategyproposedrecentlyhasbeenproventobeanefficientmethodtoacceleratetheinterpolation,whichisthemosttime-consumingpartintheiterativesub-pixeldigitalimagecorrelation(DIC)algorithms.Inthispaper,agloballook-uptablestrategywithcubicB-splineinterpolationisdevelopedfortheDICmethodbasedontheinversecompositionalGauss–Newton(IC-GN)algorithm.Theperformanceofthisstrategy,includingaccuracy,precision,andcomputationefficiency,isevaluatedthroughatheoreticalandexperimentalstudy,usingtheonewithwidelyemployedbicubicinterpolationasabenchmark.Thegloballook-uptablestrategywithcubicB-splineinterpolationimprovessignificantlytheaccuracyoftheIC-GNalgorithm-basedDICmethodcomparedwiththeoneusingthebicubicinterpolation,atatrivialpriceofcomputationefficiency.