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简介：Applyingstiffnessmigrationmethod,a3Dfiniteelementmechanicalmodelisestablishedtosimulatetheexcavationandadvanceprocesses.Byusing3Dnonlinearfiniteelementmethod,thetunnelboringmachine(TBM)excavationprocessisdynamicallysimulatedtoanalyzethestressandstrainfieldstatusofsurroundingrockandsegment.Themaximumtensilestressofsegmentringcausedbytunnelconstructionmainlyliesinarchbottomandpresentszonaldistribution.Thestressincreasesslightlyandlimitedlyinthecourseofexcavation.Themaximumandminimumdisplacementsofsegment,manifestingaszonaldistribution,distributeinarchbottomandvaultrespectively.ThedisplacementsslightlyincreasewiththeadvanceofTBMandgraduallytendtostability.

简介：岩石块的排水量和岩石结构的性质在隧道的稳定性起一个重要作用。基于关键块模型，受到集中的短时间的有压缩性的波浪的地下的隧道的动态不稳定性分析被进行。分裂和惯性的效果引起的隧道的不稳定性被区分。并且隧道的房顶轮廓弯曲的影响也被决定。

简介：在这篇论文，超导的顺序参数和Bogoliubov刺激的精力光谱为铁磁性的超导体(FS)从Bogoliubov-deGennes(BdG)方程被获得。考虑散布效果的不平的接口，我们计算射击噪音和正常金属的绝缘体的微分传导力铁磁性的超导体连接。在FS的交换精力E_h能导致微分射击噪音山峰和传导力山峰切开，这被显示出。二座切开的山峰之间的精力差别等于2E_h。散布力量的不平的接口导致传导力山峰和射击noise-to-current比率的降下，但是增加射击噪音。

简介：我们建议从微波测量Josephson隧道连接的精力松驰时间的一个非静止的方法提高了逃跑现象。与以前的方法相比，我们的方法拥有简单、精确的特征。而且，决定了精力松驰时间，我们能进一步由改变微波力量获得在微波来源和连接之间的联合力量。

简介：Thepaperconcernswiththedesignphilosophy,feasibilitystudy,aswellassomepeculiarfeaturesofIWHRwatertunnelforcavitationresearch.Thehighlightsworth-mentioningarethemaximumvelocityof35m/sandReynoldsnumberof1×10~7aswellastheprovisionofaspeciallydesignedairresorber.

简介：有一些18的Qinling隧道。488km在Qinling山的中间从Xi鈥檃n(山西省)位于铁路线到Ankan(四川省)。它是在中国的最长双的轨道铁路隧道并且在世界上占据第三个位置。根据设计，在调查的altimetric控制引起的垂直方向的突破错误为穿透脸的盒子被限制到18mm。因为铺平的线路在长度在120km上到达并且必须在2800m高度温习二座山，一阶的精确铺平和精确严肃测量应该在构造阶段被执行。在这份报纸，与最后的结果分析铺平途径，新技术的申请，一些经验以及办公室计算的地被介绍。由过细的计划，组织和观察，二个隧道结束点之间的垂直差别的最后的精确性仅仅是8mm，并且它提供可靠调查为这个大隧道工程的保证。最后，这垂直差别象114mm一样高与主要测量结果显然区分开来，这被指出。它意味着主要结果不是足够精确的。

简介：Amulti-functionsamplingsystemhasbeensetupinShanghaiShip&ShippingResearchInstitute(SSSRI)whereatestonthefluctuatingpressureoftwopropellermodelswerecarriedout.Thispaperdealswithastudyonthetechnicalproblemsconcerningthemeasurementandanalysistechniquesinvolvedinthetest.Thesamplingandprocessingprocedureofsignalisoneofthemajorfactorsaffectingtheac-curacyandstabilityofthepredictionoffluctuatingpressureinducedbypropeller.Integral-peri-odsampling,highenoughsamplingfrequencyandsuitableresolutionmustbekeptinsamplingandprocessing.Theprocedureofsamplingandprocessingshouldbevalidatedbystandardsignalcorrespondingtothebladefrequencyofdifferentordersincomparativetests.

简介：ThemodelingmethodologiesandcalculationofdynamicresponseofundergroundstructureunderRayleighwavesisinvestigatedinthispaper.FirstthefreefieldresponsesunderRayleighwavesareanalyzedandthenumericalresultsagreewellwiththetheoreticalresults.Then,theapproximateRayleighwavesareputforwardbasedonthepreliminaryre-search,andRayleighwavefieldisobtainedthroughfastFouriertransformtechnique.Takingautilitytunnelasanexample,itsdynamicresponsesunderRayleighwavesiscalculatedbyABAQUS.Theresultsdemonstratethatbendingdeformationisthemaincomponentofstructuraldeformationandthedeformationatthetopofthestructureisabouttwiceasmuchasthatatbottomofthestructure.Theeffectofsoil-structureinterfaceandtheburieddepthofundergroundstructurearealsoinvesti-gatedviaparameteranalysis.Fortheshallowburiedundergroundstructures,Rayleighwavescanbethekeyfactortocontroltheresponsesanddamageofthestructure.

简介：Aerodynamicperformanceofthehigh-altitudepropeller,especiallythecounterrotationeffects,isexperimentallystudied.Influencesofdifferentconfigurationsonastratosphericairship,included2-bladecounter-rotatingpropeller(CRP),dual2-bladesinglerotationpropellers(SRPs)and4-bladeSRP,arealsoindicated.Thisresearchindicatesthattheeffectofcounterrotationcangreatlyimprovetheefficiency.ItshowsthattheCRPconfigurationresultsinahigherefficiencythanthedual2-bladeSRPsconfigurationor4-bladeSRPconfigurationunderthesameadvanceratio,andtheCRPconfigurationalsogainsthehighestefficiencywhetherunderthesituationofprovidingthesametrustorabsorbingthesamepower.Itconcludesthat,forastratosphericairship,theCRPconfigurationisbetterthanthemultipleSRPsconfigurationoramulti-bladeSRPone.

简介：在这篇文章，跑进一条单程的二小巷的道路隧道的货车的过程用动态网孔技术和RNGk数字地被模仿吗？骚乱模型。在货车附近的短暂空气动力学的特征在三种情况中被获得：一辆单个货车，二辆货车一起并且一个接一个分别地跑进隧道的二辆货车。通过有风隧道实验的结果的比较，短暂模拟方法被验证。结果看那一辆货车是否跑进隧道，空气动力学在隧道入口附近拖系数增加，并且在进入隧道以后，方面力量被产生，更近指向隧道墙到货车。当二辆货车一起跑进隧道时，他们在50%的drag系数增加，和方面力量严厉地变化，方向在隧道入口附近变化两次。当二辆货车一个接一个跑进隧道时，在在前面的货车附近的空气动力学的特征在货车在后面上类似于一辆单个货车，而是空气动力学的力量的没有明显的变化。在三个盒子之中，当二辆货车一起跑时，空气动力学的力量有一个锋利的变化，因此一起开进一条隧道应该为安全被避免。

简介：由使用包含ATH粉末的延迟火焰的多孔的沥青人行道改进隧道火保护的一个新方法被介绍。基于缩影多孔的沥青(PA)和延迟火焰的多孔的沥青(FRPA)的设计并且进行的燃烧试验，燃烧时间和温度被学习与水泥混凝土人行道，稠密等级的高端内存区和SMA作比较。燃烧试验和人行道表演测试的结果显示FRPA象高速公路隧道的人行道材料适当、合适。

简介：Motioncontrolcanbeconsideredasthesynergisticcollaborationofmechanicalandelectricalengineering,computerscienceandinformationtechnologytoapplyacontrolledforcetoachieveusefulmotioninfluidorsoiledelectromechanicalsystems.Withthedevelopmentofcomputer,electronics,andautomaticcontroltheory,motioncontrolcomestoanewstage.Greatapplicationsarebasedonthecharacteristics,stemmingfromadvantagesofelectronicsandmoderncontroltechnologyachievements,havingaverygoodloadmatchingproperty.Currently,microprocessor-basedcontrollersareinvariablyusedinmostapplicationsofdriveelectronics.Theobjectofthisworkistodesignapositioncontrolmechanismsystem,whichcanbeusedintestsectionoflowspeedwindtunnel.Systemloadspecificationsandperformancerequirementsaregiven.Acomprehensivestudyofmathematicalmodelingofthemechanismcomponentsisgiven.Procedureforselectionofvariouscomponentswithoptimumparametersisdiscussed.Afterselectionandcalculationofsystemparameterstomeettheperformancerequirements,aPIDcontrolmethodisadopted.

简介：WorkersonOctober29completedatunnelunderChina'sYangtzeRiverforamajorgaspipelinethatwillrunfromthesouthwestprovinceofSichuantoShanghaiineastChina.Withadiameterof3.08metersandalengthof1,405meters,thetunnellaidabout20metersbeneaththeriverbed,connectingtwogaswellsoneachbankoftheYang-

简介：Thestrainmonitoringandstressanalysisofanewtypeofpost-prestressedtunnellinerwerecarriedout.Theinstrumentationblockofthetunnelliner,withthedimensionsof12.06minlength,6500mmindiameter,and650mminthickness,waspost-prestressedwiththeunbondedtendons,eachofwhichconsistsof8piecesofdouble-loopedstrandsandtheaxialspacingofthetendonsis500mm.Concretestrainmeters,rebarmeters,loadcellandzero-stressmeterswereinstalledforthestrainmonitoring.Thetensioningloadswereappliedincrementallyinthreecycles(50%,77%and100%)attheconcreteageof28dandthetensioningworklastedfor187.1h.Strainreadingsweretakenbeforeandaftereachcycleduringtensioningperiodandatthespecifiedtimeintervalaftertensioningperiod.Itisfoundthatconcretecreepdevelopedovertensioningperiodis30%oftotalstrainand41.5%ofelasticstrainrespectively.Prestressforceintheunbondedtendonandconcretestressinthelinerwereevaluatedaccordingtotheobservedstrainvariations.Bothofthemaretime-dependent,andabout5.3%,8.3%and9.0%oftheprestresslossesareobservedattheageof1d,30dand60drespectivelyafterstressing.Thedistributionofprestressinthelinerisrelativelyuniformandmeetsthedesignrequirement.

简介：Serialgradesofcementmortarspecimenshavebeentestedonthemodelofcon-crete-liningflooddischargetunnelwithorifice,Theresultsshowthatincipientcavitationerosionnumberismuchsmallerthanincipientcavitationnumber.Basedontheprincipleofbubbledy-namics,theflowspeedeffectonincipientcavitationerosionnumberforcementmortarispre-sented.

简介：Themethodologyofvisualsimulationforatunnelengineeringconstructionscheduleispresented.Visualizationofsimulationmodel,calculationandresultofconstructionschedulesimulationisrealized,andtheconstructionsimulationandtheresourceoptimizationoftunnelengineeringaremade.Ariskanalysisandadecision-makingmethodoftunnelengineeringconstructionschedulebasedonvisualsimulationarepresented.Furthermore,usingScurvetheoryandschedulemanagementmethod,thereal-timemanagementandcontrolmethodoftunnelengineeringconstructionbasedonvisualsimulationispresented.Theapplicationtothetunnelengineeringconstructionscheduleanalysisandmanagementshowsthefeasibilityandeffectivenessofthemethodpresentedinthispaper.

简介：DragreductionexperimentofthetravelingwavywallathighReynoldsnumberisconducted.Asuitoftravelingwavywalldeviceisdeveloped.Thedragforcesofthetravelingwavywallwithvariouswavespeeds(c)aremeasuredunderdifferentwaterspeeds(U)intheK15cavitationwatertunnelandarecomparedwiththatoftheflatplate.Theresultsshowthatthemeandragforceofthetravelingwavywallhavedecreasedandthenincreasedwithoscillationfrequencyincreasingatthesameflowspeed.Underdifferentflowspeeds,whentravelingwavewallreachedtotheminimumofdragforce,thecorrespondingtheratioofthewallmotionphasespeedctoflowspeedU,c/Uisslightlydifferent.Withintheparametersoftheexperiment,whenc/Ureachesacertainvalue,thedragforceofthetravelingwavywallcanbelessthanthatoftheflatplate.Thedragreductioncanbeupto42%.Furthermore,asthevalueofc/Uincreases,thetravelingwavywallcanrestraintheseparationandimprovethequalityofflowfield.

简介：AnanalyticalsolutionforscatteringofincidentSHwavesbyacircular-archillwithaconcentriccirculartunnelwasderivedbyFourier-Besselseriesexpansionandauxiliaryfunctionstechnique.Thesolutionisreducedtosolvingasetofinfinitelinearalgebraicequationsfinally.Theaccuraciesofthenumericalresultsarecheckedbytheresidualerrorsofboundaryconditionswiththetruncationorderincreasing.Thenumericalresultsshowthattheexistenceanddimensionofthetunnelhavegreateffectonmotionofthegroundsurfacenearbyanddynamicstressconcentrationofthetunnel.

简介：Thedistributionofsensorysymptomsincarpaltunnelsyndromeisstronglydependentonthedegreeofelectrophysiologicaldysfunctionofthemediannerve.Theassociationbetweencarpaltunnelsyndromeandulnarnerveentrapmentisstillunclear.Inthisstudy,wemeasuredulnarnervefunctionin82patientswithcarpaltunnelsyndrome.ThepatientsweredividedintogroupIwithminimalcarpaltunnelsyndrome(n=35)andgroupIIwithmildtomoderatecarpaltunnelsyndrome(n=47)accordingtoelectrophysiologicaldata.Sixty-oneage-andsex-matchedsubjectswithoutcarpaltunnelsyndromewereusedasacontrolgroup.Therewerenosignificantdifferencesinulnarsensorynervepeaklatenciesorconductionvelocitiesfromthe4thand5thfingersbetweenpatientswithcarpaltunnelsyndromeandthecontrolgroup.Theulnarsensorynerveactionpotentialamplitudesfromthe4thand5thfingerswerelowerinpatientswithcarpaltunnelsyndromethaninthecontrolgroup.Theratiosoftheulnarsensorynerveactionpotentialamplitudesfromthe4thand5thfingerswerealmostthesameinpatientswithcarpaltunnelsyndromeasinthecontrolgroup.Thesefindingsindicatethatinpatientswithminimaltomoderatecarpaltunnelsyndrome,thereissomeelectrophysiologicalevidenceoftractionontheadjacentulnarnervefibers.Thefindingsdonotindicateaxonaldegenerationoftheulnarnerve.