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  • 简介:<正>Duringthelastwinterholi-day,IhavereadapassagenamedTransientDaysbyZhuZiqing,writteninEng-lish.(朱自清的散文《匆匆》,附后)Ihavelearnedalessonfromit,thatis,cherishtime.

  • 标签: LESSON WINTER PASSAGE learned On the
  • 简介:Transientelectronicsareanemergingclassofelectronicswiththeuniquecharacteristictocompletelydissolvewithinaprogrammedperiodoftime.Sincenoharmfulbyproductsarereleased,theseelectronicscanbeusedinthehumanbodyasadiagnostictool,forinstance,ortheycanbeusedasenvironmentallyfriendlyalternativestoexistingelectronicswhichdisintegratewhenexposedtowater.Thus,themostcrucialaspectoftransientelectronicsistheirabilitytodisintegrateinapracticalmannerandareviewoftheliteratureonthistopicisessentialforunderstandingthecurrentcapabilitiesoftransientelectronicsandareasoffutureresearch.Inthepast,onlypartialdissolutionoftransientelectronicswaspossible,however,totaldissolutionhasbeenachievedwitharecentdiscoverythatsiliconnanomembraneundergoeshydrolysis.Theuseofsingle-andmulti-layeredstructureshasalsobeenexploredasawaytoextendthelifetimeoftheelectronics.Analyticalmodelshavebeendevelopedtostudythedissolutionofvariousfunctionalmaterialsaswellasthedevicesconstructedfromthissetoffunctionalmaterialsandthesemodelsprovetobeusefulinthedesignofthetransientelectronics.

  • 标签: 电子技术 瞬态 部分溶解 电子产品 功能材料 电子设备
  • 简介:Inthispaper,theKirchhoffstransformationispopularizedtothenonlinearheatconductionproblemwhichtheheatconductivitycanbeexpressdasamultinomialoftemperaturefirstly,theboundaryconditionofheatconductionproblemisdeterminedbyanalytics.Secondly,theincubationperoidsuperpositionandthelinearcombinationlawisemployedtosimulatethetransientphassestransformationintheprocessofheattreatmentofmaterials.Thatthebegintimeofphasetransformation,thetypeofphasetransformationandtheamountofphaseconstitutionisdeterminedsimply.Finally,thethree-dimensionDualReciprocityBoundaryElementMethodisusedtoanalysisthetotalprocessofvariousheattreatmentofcomponent,theresultsofnumericalcalculationofexamplesshowthatthemethodprovidedinthispaperiseffectivce.

  • 标签: heat treatment phase TRANSFORMATION temperature FIELD
  • 简介:STUDYONMECHANISMOFTHEBIOEFFECTSOFTRANSIENTELECTROMAGNETICPULSESTUDYONMECHANISMOFTHEBIOEFFECTSOFTRANSIENTELECTROMAGNETICPULSEW...

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  • 简介:Thispaperpresentanimprovedpreciseintegrationalgorithmfortransientanalysisofheattransferandsomeotherproblems.Theoriginalpreciseintegrationmethodisimprovedbymeanoftheinve-rseaccuracyanalysissothattheparameterN,whichhasbeentakenasaconstantandanindependentpa-rameterwithoutconsiderationoftheproblemsintheoriginalmethod,canbegeneratedautomaticallybythealgorithmitself.Thus,theimprovdealgorithmisadaptiveandtheaccucacyofthealgorithmisnotdependentonthelengthofthetimestepintheintegrationprocess.Itisshownthatthenumericalresultsobtainedbythemethodproposedaremoreaccuratethanthoseobtainedbytheconventionaltimeintegrationmethodssuchasthedifferencemethodandothers.Fourexamplesaregiventodemonstratethevalidity,accuracyandeffi-ciencyofthenewmethod.

  • 标签: heat TRANSFER ANALYSIS PRECISE INTEGRATION method
  • 简介:WepresentthenumericalanalysisofacoupledmethodforthenumericalsimulationoftransientviscoelasticflowobeyingadifferentialconstitutiveequationwithaNewtonianviscosity.TheschemeusedisbasedonEulerimplicitmethodintimeandmaintainsateachtimestepacoupleofthevelocityuandtheviscoelasticpartofthestressσ.Approximationinspaceismadebyfiniteelementmethod.Theapproximatestress,velocityandpressureare,respectively,P1-continuous,p2-continuous,andp1continuous.Upwindingneededforconvectionofσismadebya'StreamlineUpwindPetrovGalerkin'method(SUPG).

  • 标签: 数字分析 瞬时粘弹性流动 上风法 牛顿粘度 非牛顿流体 流体力学
  • 简介:Wedevelopedatransientmodelforactin-basedmotility.Diffusionofactinmonomerswasincludedintheformulationanditsinfluenceonthespeedofactin-drivencargoswasexaminedindetail.Ourresultsclearlydemonstratedhowactinpolymerizationacceleratescargosthatareinitiallystationary,aswellashowsteady-stateiseventuallyreached.Wealsofoundthat,duetopolymerizationanddiffusion,actinmonomerconcentrationneartheloadsurfacecanbesignificantlylowerthanthatintherestofth...

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  • 简介:DetailedanalysisontransientcharacteristicsofECLcircuitsareperformedinthispaper,thenarelativelyexactpropagationdelayexpressionappliedforalltemperaturesispresented.Thecryogeniccharacteristicsofsomedominantparameterscontributedtopropagationdelayarealsodiscussed.Themodelachievedissuitableforoptimumdesignsofhighspeeddevicesandcircuitsatalltemperatures.

  • 标签: ECL CIRCUIT Low temperature TRANSIENT CHARACTERISTIC
  • 简介:在这篇评论文章,我们在场为在nanodevices的短暂电子动力学的一个非平衡量运输理论在费米子与路径积分方法基于准确主人方程发源协调状态的表示。把准确主人方程用于nanodevices,我们也与Keldyshnonequilibrium格林功能建立减少的密度矩阵和短暂的量运输电流的连接。理论使我们能从接触与背反应效果在nanostructures学习短暂的量运输,与non-Markovian驱散和decoherence充分被考虑。在应用程序,我们利用理论到特定的量运输系统,许多量decoherence和量包含non-Markovian存储器效果的运输现象在接触的任意的起始的温度在短暂、静止的情形被调查。

  • 标签: 量运输 主人方程 打开系统 NANOSTRUCTURES
  • 简介:ThetransientresponsetolongitudinalimpactofflexiblerodswithHertzcontactiscloselyrelatedtotheextentofdeformationswithdifferentimpactparameters.BymeansofLS-DYNA,fordifferentradiusanddifferentspeeds,thelongitudinalimpactofahammerwitharoundedendonadrillrodisnumericallysimulatedinthisarticle.Simulationsdemonstratethatthereisanobviousdif-ferencebetweenanalyticalsolutionandnumericalsolutiononconditionofshortcurvatureradius.Inthecircumstancecontactpressureincreases,theboundaryoftheyieldzoneexceedsthatofthecontactzone,andthesignificantplasticdeformationreducestheintensityofcontactpressurepulse.Contactforce-timecurvesinloadingandunloadingphasesshiftdown.Thenumericalsolutionisingoodagree-mentwithanalyticalsolutiononconditionoflargecurvatureradiusandimpactspeeds.Thedeforma-tionofyieldregionisconstrainedbythesurroundingelasticregionandnosignificantplasticdeforma-tionappears.

  • 标签: 数值模拟 瞬态响应 柔性体 HERTZ接触 LS-DYNA 赫兹
  • 简介:TheincorrectdeductionofequationsintheresearchworksdevotedtothestudiesoftransientstressincylindricallyorthotropictubesanddonebyKardomateas(JournalofAppliedMechanics,1989,1990)leadstothewrongresults.Theerrata(1991)correctthedeductionerror,butdonotgivetherightnumericalresults.Allerrorsarecorrected,andtheMathematicaisadoptedtosolvethelargeargumentproblemforBesselfunction.Atheoreticalsolutionofthetransientthermalstressesintubeswithuniformformispresented,andanumericalexampleisstudied.

  • 标签: 柱形各向异性管 复合管 瞬时热压力 贝塞尔函数 弹性力学
  • 简介:超声的短暂的地水平地极化了砍2/2散发的波浪压电的合成正常探查被分析。二不同表面力量来源的分析的地解决方案被推出,中央剖面图上的短暂排水量地分发被数字计算阴谋。直接波浪和边波浪以及头波浪在阴谋清楚地被观察。时间域波形的试验性的结果符合了理论预言,它在变换器的短暂的域附近支持了理论、数字的结果。

  • 标签: 剪切波 声波探测 超声波 压电复合物
  • 简介:AbstractImportance:Acute respiratory infections are quite prevalent in children. Transient hyperphosphatasemia (TH) is defined as the transient elevation of serum alkaline phosphatase (ALP) level, which occurs mainly in infants and children without liver or bone disorders. Although no apparent cause has been identified, a possible association of respiratory infections with TH has been reported in the literature.Objective:In this study, we aimed to investigate the association between TH and respiratory infectious diseases.Methods:We collected the results of biochemical investigations, including ALP level, for a period of 5 years in our hospital. We then examined the patients with transiently elevated ALP levels of > 2000 U/L.Results:During the observation period, 1501 blood samples were collected from 1097 patients. Marked elevation of serum ALP level was observed in 12 patients. All patients with hyperphosphatasemia, except for one with Fanconi syndrome attributable to the underlying Wilson’s disease, were aged < 5 years and were diagnosed with TH. Ten of these 11 patients with TH had acute respiratory infections. Marked ALP elevation was not found in any patients with non-inflammatory diseases. ALP isoenzyme profiles showed a characteristic pattern in all six patients in whom the ALP isoenzyme test was conducted.Interpretation:Our results suggest an association between respiratory infections and TH. The consideration of TH in patients with acute respiratory infections may lead to earlier and accurate diagnosis of this condition, thereby avoiding unnecessary medical interventions.

  • 标签: Alkaline phosphatase Respiratory infection Transient hyperphosphatasemia Isoenzyme
  • 简介:ONTHEHIGHPRECISIONADAPTIVEOPENBOUNDARYCONDITIONSFORTRANSIENTWAVES¥ZouGuang-yuan(Dept.ofMechanicsandEngineeringSciences,Peking...

  • 标签: ADAPTIVE open BOUNDARY conditions high PRECISION
  • 简介:在这份报纸,为multiferroic的三维的有限元素的明确的表达合成为它的短暂分析被开发并且实现进商业软件ABAQUS。首先,一个特殊三维的八节点的稳固的元素被设计处理用橡皮做的合成的multiferroic,压电,并且piezomagnetic材料。第二,为这个最新发达的元素的一个自定义子程序被实现进ABAQUS。最后,双性人分层的multiferroic的短暂回答合成被使用直接时间集成方法计算。二个典型磁性的潜在的信号,高斯和Ricker脉搏,被用于与刺激的各种各样的时间持续时间合成。短暂反应能被输入实质地影响的导致的电场表演发信号,它能为最强壮的电的输出被调节。

  • 标签: 瞬态响应 复合板 ABAQUS 三维有限元 复合材料
  • 简介:AbstractFat embolism syndrome (FES) is a serious life-threatening manifestation of the fat embolism phenomenon characterized by Bergman’s triad of dyspnea, petechiae and mental confusion. While fat embolization into systemic circulation is common, FES occurs in a meagre 0.05%-3% of patients having isolated long bone fractures. Though visual symptoms are commonly attributed to fat embolism retinopathy and is a later occurrence, it may not always be the case. Cortical blindness has been seldom reported in association with FES, and less so as a presenting complaint. Furthermore, no previous literature has described the same in context of an isolated tibia fracture. We report a 20-year-old gentleman with an isolated right tibia shaft fracture who developed sudden onset diminution of vision in both eyes less than 24 h following trauma with no other complaints. Lack of any remarkable ophthalmoscopic findings or other symptoms left us with a diagnostic conundrum. He later went on to develop altered mentation, hypoxia and generalized tonic-clonic seizures with subsequent MRI revealing multiple cerebral fat emboli also involving both occipital lobes. Supportive measures were instituted and his general condition as well as vision gradually improved following which he underwent plate fixation of the fracture under spinal anaesthesia. The perioperative period was uneventful and he was discharged following staple removal. At one month of follow-up, the patient had no residual visual field defects or neurological deficits. Though FES is rare among isolated tibia fractures, this clinical catastrophe may strike in any unsuspected setting thereby warranting a high index of suspicion to ensure early diagnosis and improved patient outcomes.

  • 标签: Fat embolism Cortical blindness Bone fractures
  • 简介:Asemi-analyticalmethodintimedomainispresentedforanalysisofthetransientresponseofnonuniformtransmissionlines.Inthismethod,thetelegraphequationsintimedomainisdifferencedinspacedomainfirst,andistransformedintoasetoffirst-orderdifferentialequationsofvoltageandcurrentwithrespecttotime.Byintegratingthesedifferentialequationswithrespecttotime,andprecisecomputation,thesolutionofthesedifferentialequationscanbeobtained.Thismethodcansolvethetransientresponseofvariouskindsoftransmissionlineswitharbitraryterminalnetworks.Particularly,itcananalyzethenonuniformlineswithinitialconditions,forwhichthereisnoexistingeffectivemethodtoanalyzethetimeresponsesofar.Theresultsobtainedwiththismethodarestableandaccurate.Twoexamplesaregiventoillustratetheapplicationofthismethod.

  • 标签: 传输线 非线性终端网络 初始条件 瞬时响应