简介:Accesscontrolinmulti-domainenvironmentsisoneoftheimportantquestionsofbuildingcoalitionbetweendomains.OnthebasisofRBACaccesscontrolmodel,theconceptsofroledelegationandrolemappingareproposed,whichsupportthethird-partyauthorization.Then,adistributedRBACmodelispresented.Finallytheimplementationissuesarediscussed.
简介:传统的控制策略有困难在地震刺激下面处理结构,时间变量特征和构造控制系统的参数不确定性的非线性的行为。与模糊控制相结合的off-and-towards-equilibrium(OTE)策略在这篇论文被介绍克服这些困难。根据OTE策略,控制力量从在结构,令人激动的力量和控制力量的运动之间的一种机械关系的观点被设计。OTE策略的优点是它能被用于许多控制系统。以便评估建议策略的表演,地震表演一三故事砍用一个模糊逻辑控制器(FLC)与一个活跃的腱系统(ATS)造被学习。模糊控制器的主要优点是它处理结构的任何非线性的行为的固有的坚韧性和能力。然而,没有设计指南为FLC建立相应检核尺桌子。为FLC基于建议策略,在学习下面与大楼联系的一张检核尺桌子被开发,它然后允许一个详细算法的形成。在这研究获得的结果证明建议策略比线性二次的管理者(LQR)稍微好表现策略,当在LQR控制器上拥有几个优点时。因而,建议策略的可行性和有效性被验证。
简介:Inthispaper,awavelet-filteredgenetic-neuro-fuzzy(WGNF)controlsystemdesignframeworkforresponsecontrolofahighwaybridgeundervariousearthquakeloadsisdiscussed.TheWGNFcontrollerisdevelopedbycombiningfuzzylogic,discretewavelettransform,geneticalgorithms,andneuralnetworksforuseasacontrolalgorithm.ToevaluatetheperformanceoftheWGNFalgorithm,itistestedonahighwaybridgeequippedwithhydraulicactuators.Itcontrolstheactuatorsinstalledontheabutmentsofthehighwaybridgestructure.Variousearthquakesusedasinputsignalsincludeanartificialearthquake,theEl-Centro,Kobe,NorthPalmSprings,TurkeyBolu,Chi-Chi,andNorthridgeearthquakes.ItisprovedthattheWGNFcontrolsystemiseffectiveinmitigatingthevibrationofthehighwaybridgeunderavarietyofseismicexcitation.
简介:Ahybridcontrolplatformisinvestigatedinthispapertomitigatemicrovibrationstoagroupofvibrationsensitiveequipmentinstalledinamicroelectronicsfacilitysubjecttonearbyroadvehicle-inducedhorizontalandverticalgroundmotions.Thehybridcontrolplatform,onwhichmicroelectronicsequipmentisinstalled,ismountedonabuildingfloorthroughaseriesofpassivemountsandcontrolledbyhydraulicactuatorsinbothhorizontalandverticaldirections.Thecontrolplatformisanelasticbodywithsignificantbendingmodesofvibration,andasub-optimalcontrolalgorithmisusedtomanipulatethehydraulicactuatorswithactuatordynamicsincluded.Thefiniteelementmodelandtheequationsofmotionofthecoupledplatform-buildingsystemarethenestablishedintheabsolutecoordinatetofacilitatethefeedbackcontrolandperformanceevaluationoftheplatform.Thehorizontalandverticalgroundvibrationsatthebaseofthebuildinginducedbynearbymovingroadvehiclesareassumedtobestationaryrandomprocesses.Atypicalthree-storymicroelectronicsbuildingisselectedasacasestudy.Thecasestudyshowsthattheverticalvibrationofthemicroelectronicsbuildingishigherthanthehorizontal.TheuseofahybridcontrolplatformcaneffectivelyreducebothhorizontalandverticalmicrovibrationsofthemicroelectronicsequipmenttothelevelwhichsatisfiesthestringentmicroscalevelocityrequirementspecifiedintheBoltBeranek&Newman(BBN)criteria.
简介:Underwatervehicleplaysanimportantroleinoceanengineering.Depthcontrolbyfinisoneofthedifficultiesforunderwatervehicleinmotioncontrol.Depthcontrolisindirectduetothefreedomcouplingbetweentrimandaxialmotion.Itincludesthemethodofdynamicanalysisandlift-resistance-coefficientexperimentandtheoryalgorithm.Byconsideringthecurrentspeedanddepthdeviation,comprehensiveinterpretationisusedinobject-planninginstruction.Expecteddepthistransformedintoexpectedtrim.Dynamicoutputfluctuationcanbeavoided,whichiscausedbylinearmappingofdeviation.Itissteadyandaccurateforthemotionofcontrolledunderwatervehicles.Thefeasibilityandefficiencyofthecontrolmethodaretestifiedinthepoolandnaturalareaforexperiments.
简介:在这份报纸,一个最佳的H鈭?控制算法被用于在一座有多层楼的大楼的第一个故事安装由于地震刺激减少它的interstory飘移的一个活跃的腱系统的设计。完成最佳的控制性能并且保证控制系统的稳定性,选择控制参数纬和伪的最佳策略被开发。分析表情上面并且纬和伪的更低的界限与州的反馈控制为一个单个degree-of-freedom系统被获得。为纬和伪的选择范围图形地被定义以便控制系统总是是稳定的,控制性能比由常规LQR控制算法好。来自在真实地震刺激下面的一座控制三故事的大楼的数字结果证明山峰第一interstory飘移能显著地在10%造的重量附近与最大的控制力量被减少。一份最佳设计流动图表被提供。为推迟时间的结构,另外,这研究给了明确的公式计算纬和伪的批评价值。系统稳定性和控制性能能因此甚至与时间延期被保证。
简介:Inthispaper,anewhybridcontroltechnique,basedonacombinationofbase-isolationandsemi-activevariablestiffness/dampinginasuperstructure,ispresented.Toillustratetheefficiencyoftheproposedcontrolsystem,modeltestsonamini-electromagneticshakingtableandanumericalsimulationwereperformed.Thetestandnumericalcalculationresultsindicatethatthisnewhybridcontrolmodewithadditionaldampingandsmalleradditionalstiffnesscanachieveabettercontrolefficiency.
简介:Anewapproachtoreducingtheseismicresponseofspatialstructureswithmagneto-rheological(MR)dampersispresentedinthispaper.TheGeneticAlgorithmwithsmallpopulations(μGA)isusedtooptimizethecontrolfortheMRdamperstoreducestructuralvibration,whichisdifficulttoachieveusingclassicaloptimalcontrol.TheadvantagesofμGAaretheuseofglobalpropertiesandthatfewerconditionsarerequiredtoobtaintheoptimalfunction.Numericalresultsdemonstratetheeffectivenessoftheproposedmethodinreducingtheseismicresponseofstructures.
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简介:Inthisstudy,theentiremitochondrialDNA(mtDNA)controlregion(CR)ofPholisfangiwasamplifiedviapolymerasechainreactionfollowedbydirectsequencing.ThelengthofthemtDNACRconsensussequenceofP.fangiwas853bpinlength.Inaccordancewiththerecognitionsitesaswerepreviouslyreportedinfishspecies,themtDNACRsequenceofP.fangicanbedividedinto3domains,i.e.,theextendedterminalassociatedsequence(ETAS),thecentralconservedsequenceblock(CSB),andtheCSBdomain.Inaddition,thefollowingstructureswereidentifiedinthemtDNACRsequenceofP.fangi:2ETASsintheETASdomain(TASandcTAS),6CSBsinthecentralCSBdomain(CSB-FtoCSB-A),and3CSBsintheCSBdomain(CSB-1toCSB-3).ThesedemonstratedthatthestructureofthemtDNACRofP.fangiwassubstantiallydifferentfromthoseofmostotherfishspecies.ThemtDNACRsequenceofP.fangicontainedoneconservedregionfrom656bpto815bp.Similartomostotherfishspecies,P.fangihasnotandemrepeatsequencesinitsmtDNACRsequence.PhylogeneticanalysisbasedonthecompletemtDNACRsequencesshowedthattherewerenogeneticdifferenceswithinP.fangipopulationsofthesamegeographicaloriginandbetweenP.fangipopulationsofdifferentgeographicalorigins.
简介:AnobviousmotivationofthispaperistoexaminetheeffectivenessofthelateralvibrationcontrolofajackettypeoffshoreplatformwithanAMDcontroldevice,inconjunctionwithH2controlalgorithm,whichisanoptimalfrequen.cydomaincontrolmethodbasedonminimizationofH2normofthesystemtransferfunction.Inthisstudy,theoffshoreplatformismodelednumericallybyuseofthefiniteelementmethod,insteadofalumpedmassmodel.Thisstructuralmodelislatersimplifiedtobesingle-degree-of-freedom(SDOF)systembyextractingthefirstvibrationmodeofthestruc.ture.Thecorresponding″generalized″waveforceisdeterminedbasedonananalyticalapproximationofthefirstmodeshapefunction,thephysicalwaveloadingbeingcalculatedfromthelinearizedMorisonequation.Thisapproachfacilitatesthefilterdesignforthegeneralizedforce.Furthermore,thepresentpaperalsointendstomakenumericalcompari.sonbetweenH2activecontrolandthecorrespondingpassivecontrolusingaTMDwiththesamedeviceparameters.
简介:ThereareplentyofSinianandCambrianpotentialshalegasresourcesinSouthChina,whichischaracterizedbyhighthermalevolutiondegrees,poordrillingperformancesandonlyoccursinlocalareas.Takingtheprinciple“hightofindlow”isthekeyissuetoachievingabreakthroughinoldershale.ChinaGeologicalSurveydrilledintheperipheryoftheProterozoicbasement,i.e.theHuanglinganticline,inthewesternHubei,andHannanpaleocontinentinthesouthernShanxi.Itreceivedhigh-qualitygas-bearingshalewithrelativelylowRointheinLowerCambrianNiutitangformationandSinianDoushantuoformation.BasedongeologicalconditionsofshalegasreservoirsintheHuanglinganticline,thispaperputsforwardthenewmodelnamed“Controloverreservoirsbyperipheryofbasement”aboutshalegasaccumulation,suggestingthattheshaledepositedinadeepwatercontinentalshelfintheperipheryofthebasementischaracterizedbyshallowburial,ashortburialtime,stabletectonics,relativelylowthermalevolutiondegrees,andshalegasreservoirsinagoodcondition.TheshaleoftheSinian-CambrianstratadepositedindeepwatercontinentalshelvesintheperipheryofChuanzhongpaleo-upliftinSichuan,HannanpaleocontinentinthesouthernShanxi,HuanglinganticlineinwesternHubeiandJiangnang-Xuefengpaleo-upliftinHunanandGuizhouprovincehavegoodshalegasexplorationpotential.
简介:ThereisalownutrientlevelintheAoshanBay.InJune1999,thechemicaladjustmentandcontrolexperimentwasmadeintheAoshanBay.Followingtractsinvestigationwascarriedoutbeforetheexperimentandonthe1st,2nd,4th,5th,6thand45thday/aftertheexperiment.Whilethevarianceofamountofphytoplankton,thereplacementofsuperiorspeciesandthespeciescompositionofphytoplanktonwereresearched.TheresultsshowthattheamountofphytoplanktonintheAoshanBayrisesgraduallyaftertheexperiment.CeratiummacrocerosCleveofpyrophytawasthedominantspeciesbeforetheexperiment,itsdominantindexwas37.7%.Sixdaysaftertheexperiment,itsdominantindexdroppedto17.6%.MeanwhilethedominantindexofAsterionellajaponicsCleverosefrom7.1%to39.2%,itbecamethefirstdominantspecies.Forty-fivedaysaftertheexperiment,theamountofphytoplanktonintheAoshanBaywas5.15to137.32timesmorethanthatin1997.
简介:ByimplementingtheARGOprogram,alargenumberofT-Sprofilescanbeobservedintheworldocean.However,itisverydifficulttoexaminechangesofthesensitivityofthesensorsequippedattheARGOfloats,becauseitisdifficulttounderstandtheirconditionintheseaandthereliabilityofthedata.Qualitycontrolmustbedoneinordertoavoidthewrongconclusiondeducedfromthewrongdata.OneoftherealisticmethodsforqualitycontroloftheARGOdataisthecomparisonwiththelocalclimatology.HighqualityclimatologicalT-SmodelsinnorthwestPacifichavebeenbuiltbasedontheNansenbottledataandCTDdataforthequalitycontrolinNMDIS.ThemodelsareusedtochecktheARGOdatainthisareaandhavegotgoodresult.
简介:Thepurposeofthisstudyistoinvestigatetheeffectivenessofmulti-tunedmassdampers(MTMD)onmitigatingvi-brationofanoffshoreoilplatformsubjectedtooceanwaveloading.Anoptimaldesignmethodisusedtodeterminetheop-timaldamperparametersunderoceanwaveloading.TheforceonthestructureisdeterminedbyuseofthelinearizedMorisonequation.InvestigationonthedeckmotionwithandwithoutMTMDonthestructureismadeunderdesigncondi-tions.TheresultsshowthatMTMDwiththeoptimizedparameterssuppresstheresponseofeachstructuralmode.ThesensitivityofoptimumvaluesofMTMDtocharacteristicwaveparametersisalsoanalyzed.ItisindicatedthatasingleTMDonthedeckofaplatformcanhavethebestperformance,andthesmallthedampingvalueofTMD,thebetterthevibrationcontrol.
简介:摘要:在北Qaidam盆的侏罗记煤措施的分发被地区性的结构显然控制。基于煤田探索的存在数据并且与煤田地下室结构,主要差错的特征,和煤措施的分发的分析结合了,这份报纸向前在北Qaidam盆带给煤田的一个计划构造师的单位和控制煤的结构的式样的定义。煤措施的分发的结构控制进一步被讨论。煤的分发从东方从北方测量进带状配列的特征到南方和块到西方的后来,Indosinian导致了的地区性的构造活动的几个阶段。结果显示结构的变丑在三的前面是最强烈的高举系上带子,它被戳的联合描绘。煤措施被高举到浅形成,并且对容易被利用,但是因为严重损坏,矿的规模是小的。相反,压力和紧张在三消沉是弱的,与主要是的控制煤的结构的式样戳褶层和戳单斜层联合。在消沉的煤的分发是相对稳定的。消沉的更浅的部分将在北Qaidam盆为煤资源的探索和开发成为关键区域。
简介:Astheexplorationandexploitationofoilandgasproliferatethroughoutdeepwaterarea,therequirementsonthereliabilityofdynamicpositioningsystembecomeincreasinglystringent.Thecontrolobjectiveensuringsafetyoperationatdeepwaterwillnotbemetbyasinglecontrollerfordynamicpositioning.Inordertoincreasetheavailabilityandreliabilityofdynamicpositioningcontrolsystem,thetripleredundancyhardwareandsoftwarecontrolarchitecturesweredesignedanddevelopedaccordingtothesafespecificationsofDP-3classificationnotationfordynamicallypositionedshipsandrigs.Thehardwareredundantconfigurationtakestheformoftriple-redundanthotstandbyconfigurationincludingthreeidenticaloperatorstationsandthreereal-timecontrolcomputerswhichconnecteachotherthroughdualnetworks.Thefunctionofmotioncontrolandredundancymanagementofcontrolcomputerswereimplementedbysoftwareonthereal-timeoperatingsystemVxWorks.Thesoftwarerealizationoftaskloosesynchronization,majorityvotingandfaultdetectionwerepresentedindetails.Ahierarchicalsoftwarearchitecturewasplanedduringthedevelopmentofsoftware,consistingofapplicationlayer,real-timelayerandphysicallayer.ThebehavioroftheDP-3dynamicpositioningcontrolsystemwasmodeledbyaMarkovmodeltoanalyzeitsreliability.Theeffectsofvariationinparametersonthereliabilitymeasureswereinvestigated.Thetimedomaindynamicsimulationwascarriedoutonadeepwaterdrillingrigtoprovethefeasibilityoftheproposedcontrolarchitecture.