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500 个结果
  • 简介:机电的致动器广泛地在许多工业应用被使用。通常有一些限制,在一个设计系统存在。这份报纸建议一个简单方法为机电的致动器设计抑制控制器。控制器合并在内部模型控制利用的想法并且为预兆的控制建模。他们与统一用标准控制系统结构被设计否定反馈。控制器的结构象设计过程一样相对简单。处理机制的输出限制基于许多时间向前走的控制植物行为的预言。机制增加控制控制植物的性能和安全。建议控制器提供的好处在在二个机电的致动器的控制系统执行的真实实验被表明了:一台DC马达和一个electrohydraulic致动器。

  • 标签: 控制系统结构 内模控制器 机电作动器 输出 电动执行机构 模型预测控制
  • 简介:Inthispaper,weformulateasingle-speciesmodelofcontraceptioncontrolwithwhitenoiseonthedeathrate.Firstly,theuniquenessofglobalpositivesolutionofthemodelisproved.Secondly,uniformlyboundedmeanofsolutionisobtainedbyusingtheLiyapunovfunctionandChebyshevinequality.Lastly,stochasticglobalasymptoticstabilityofzeroequilibriumsisanalyzed.

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  • 简介:这份报纸处理与控制不了的不稳定的linearization为非线性的系统的一个类调遣controlproblems的适应实际输出。设计一个光滑的适应调遣控制器解决几何、动态的任务withan的objectiveis任意的小稳定的追踪错误。增加一个力量综合者和robustrecursive设计技术的方法被采用强迫系统产量追踪一条需要的路径和makethe追踪速度沿着路径跟随需要的速度。一个例子被考虑,simulationresults被给。建议设计过程能被这个例子的使用说明。

  • 标签: 非线性系统 自适应输出机动控制 实际输出跟踪 回归设计技术
  • 简介:Ahybridcontrolplatformisinvestigatedinthispapertomitigatemicrovibrationstoagroupofvibrationsensitiveequipmentinstalledinamicroelectronicsfacilitysubjecttonearbyroadvehicle-inducedhorizontalandverticalgroundmotions.Thehybridcontrolplatform,onwhichmicroelectronicsequipmentisinstalled,ismountedonabuildingfloorthroughaseriesofpassivemountsandcontrolledbyhydraulicactuatorsinbothhorizontalandverticaldirections.Thecontrolplatformisanelasticbodywithsignificantbendingmodesofvibration,andasub-optimalcontrolalgorithmisusedtomanipulatethehydraulicactuatorswithactuatordynamicsincluded.Thefiniteelementmodelandtheequationsofmotionofthecoupledplatform-buildingsystemarethenestablishedintheabsolutecoordinatetofacilitatethefeedbackcontrolandperformanceevaluationoftheplatform.Thehorizontalandverticalgroundvibrationsatthebaseofthebuildinginducedbynearbymovingroadvehiclesareassumedtobestationaryrandomprocesses.Atypicalthree-storymicroelectronicsbuildingisselectedasacasestudy.Thecasestudyshowsthattheverticalvibrationofthemicroelectronicsbuildingishigherthanthehorizontal.TheuseofahybridcontrolplatformcaneffectivelyreducebothhorizontalandverticalmicrovibrationsofthemicroelectronicsequipmenttothelevelwhichsatisfiesthestringentmicroscalevelocityrequirementspecifiedintheBoltBeranek&Newman(BBN)criteria.

  • 标签: 微小振动 道路交通 微电子工程 有限元分析
  • 简介:Thecenterlinesegregationincontinuouscastingsteelisknowntobeformedbytheinterdendriticenrichedliquidflowatthesolidificationendinstrand.Atpresent,severalmethods,suchasthermalsoftreduction,electromagneticstirringanddynamicsoftreduction,areavailabletoreducethecentersegregationandtoimprovetheinternalquality.Althoughsomemethodscouldalleviatecentersegregationtosomeextent,theycanalsogiverisetonewproblems.Forinstance,thermalsoftreductioncanleadtosurfacecrackingduringcastingofsomesteelsandelectromagneticstirringcanresultinwhiteband.Dynamicsoftreductionisaneffectivetechnologyfortheimprovementofstrandqualityincontinuousslabcasting.Inthispaper,thekeyparametersofdynamicsoftreductiontechnology,suchassoftreductionregion,thetotalreductionamount,forlowcarbonsteelhavebeenstudiedbasedonexperimentalandtheoreticalanalysis.Thesoftreductionregionwasrelatedtothesegregationofchemicalcomposition,slabbulgingofnarrowsideandavoidinginternalcrackofslab.Thetotalreductionamountwascomposedofnaturalthermalshrinkageandactualreductionamountdependingoncriticalstrain.Forlowcarbonsteelwithslabdimensionof(950-1950)mm×170mm,thesolidfractionrangeinsoftreductionregionwasrecommendedfrom0.4to0.8,thetotalreductionamountwas2.0-2.8mm,andtheoptimizedreductionratewas0.4-1.2mm/min,respectively.Furthermore,adynamicsoftreductionsystemincontinuousslabcasting,VisualCast-Dynamic,hasbeendevelopedbymultithreadingmethod.Itdemonstratedthatthedynamicsoftreductionmodelinthisstudywascorrectwiththeabilityofonlinecontrol.

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  • 简介:Thispaperconsiderstheoptimaltrafficsignalsettingforanurbanarterialroad.Byintroducingtheconceptsofsynchronizationrateandnon-synchronizationdegree,amathematicalmodelisconstructedandanoptimizationproblemisposed.Then,anewiterativealgorithmisdevelopedtosolvethisoptimaltrafficcontrolsignalsettingproblem.Convergencepropertiesforthisiterativealgorithmareestablished.Finally,anumericalexampleissolvedtoillustratetheeffectivenessofthemethod.

  • 标签: 交通信号控制 干线道路 联合优化 城市 信号设置 迭代算法
  • 简介:Recently,someresearchesindicatethatpositivefeedbackcanbenefitthecontrolifappropriatetimedelayisintentionallyintroducedintocontrolsystem.However,mostworkistheoreticalonebutfewareexperimental.Thispaperpresentstheoreticalandexperimentalstudiesofdelayedpositivefeedbackcontroltechniqueusingaflexiblebeamasresearchobject.Thepositivefeedbackweightingcoefficientisdesignedbyusingtheoptimalcontrolmethod.Theavailabletimedelayisdeterminedbyanalyzing...

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  • 简介:Thispaperdevelopesatemperaturecontrolsysteminordertocarryoutarealtimeandcontinuousobservationonlivingcellsunderthemicroscope.Inthissystem,transparentindiumtinoxid(ITO)conductivefilmwasusedasaheater,temperaturewasmeasuredbythetemperaturedependenceofresistancebehavioroftheITOfilm,C8051F340single-clupwasusedasthecontrolhardwarecore,andthemodifiedPIDalgorithmandpulsewidthmodulation(PWM)wereadoptedasthekeycontrolsoftwareprograms.Thetemperaturesystemhadasimplestructurewithoutaddedtemperaturesensor,anuniformtemperaturedistributionwithin±1℃ontheITOfilmsurfaceandtemperaturecontrolprecisionof±0.2℃couldbeobtained.ThesystemcouldmaintainagoodgrowthstateforBHK-21livingcellunderthemicroscopefor48h.

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  • 简介:ThisletterproposesaratecontrolalgorithmforH.264videoencoder,whichisbasedonblockactivityandbufferstate.ExperimentalresultsindicatethatithasanexcellentperformancebyprovidingmuchaccuratebitrateandbettercodingefficiencycomparedwithH.264.ThecomputationalcomplexityofthealgorithmisreducedbyadoptinganovelblockactivitydescriptionmethodusingtheSumofAbsoluteDifference(SAD)of16×16mode,anditsrobustnessisenhancedbyintroducingafeedbackcircuitatframelayer.

  • 标签: 视频编码 H.264标准 速率控制 MPEG
  • 简介:Aspartofacomprehensiveenvironmentalmanagementsystem,manycountriesestablishemissioncontroltargetsformassemissionsofapollutant.Suchtargetsareoftenthekeyobjectiveofanenvironmentalpolicy,suchasanemissiontradingprogram.InChina,however,itismorethanjustanobjectiveofoneparticularpolicy;ithasbecomeaconceptthathasinfluencedmanynationalenvironmentalpoliciesandactivities.Theobjectiveofthisarticleistoreviewtheimplementationofthetotalemissioncontrolpolicyinthepast10yearsandexploreemergingissuesinitsimplementation.Thearticlehasthreesections:asummaryoftheimplementationexperience,issueswiththedesignandimplementationofthepolicy,andpolicyrecommendations.

  • 标签: 环境政策 总量控制 中国 排放污染物 批判 环境管理制度
  • 简介:Anexperimentalinvestigationonairfoil(NACA64-215)shockcontrolisperformedbyplasmaaerodynamicactuationinasupersonictunnel(Ma=2).Theresultsofschlierenandpressuremeasurementshowthatwhenplasmaaerodynamicactuationisapplied,thepositionmovesforwardandtheintensityofshockattheheadoftheairfoilweakens.Withtheincreaseinactuatingvoltage,thetotalpressuremeasuredattheheadoftheairfoilincreases,whichmeansthattheshockintensitydecreasesandthecontrolefectincreases.Thebestactuationefectiscausedbyupwind-directionactuationwithamagneticfield,andthendownwind-directionactuationwithamagneticfield,whilethecontrolefectofaerodynamicactuationwithoutamagneticfieldisthemostinconspicuous.Themeanintensityofthenormalshockattheheadoftheairfoilisrelativelydecreasedby16.33%,andthenormalshockintensityisrelativelyreducedby27.5%when1000Vactuatingvoltageandupwind-directionactuationareappliedwithamagneticfield.ThispapertheoreticallyanalyzestheJouleheatingefectgeneratedbyDCdischargeandtheLorentzforceefectcausedbythemagneticfield.Thedischargecharacteristicsarecomparedforallkindsofactuationconditionstorevealthemechanismofshockcontrolbyplasmaaerodynamicactuation.

  • 标签: 等离子体 冲击控制 气动 翼型 激励 驱动电压
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  • 简介:这篇论文在一种控制体系结构上研究为自治在水下车辆(AUV)。在描述AUV控制系统的混合性质以后,我们在场层次AUV控制体系结构。建筑学在三层被组织:使命层,任务层和实行层。声明监督人和任务协调人是处理分离事件的二个关键模块,因此我们详细描述这二个模块。最后,我们执行了一系列测试验证这体系结构。测试结果证明AUV能有效地并且安全地执行自治使命。我们能断定控制建筑学有效、实际。

  • 标签: 递阶控制 水下交通工具 设计方案 协调器
  • 简介:Thedesignandperformanceanalysisofnetworkedcontrolsystemswithrandomnetworkdelayintheforwardchannelisproposed,whicharedescribedinastate-spaceform.Anewcontrolschemeisusedtoovercometheeffectsofnetworktransmissiondelay,whichistermednetworkedpredictivecontrol(NPC).Furthermore,threedifferentwaystochoosecontrolinputarediscussedandtheperformancesareanalyzed,respectively.Bothreal-timesimulationsandpracticalexperimentsshowtheeffectivenessofthecontrolscheme.

  • 标签: 控制系统 NPC 系统分析 系统理论
  • 简介:Adissipative-basedadaptiveneuralcontrolschemewasdevelopedforaclassofnonlinearuncertainsystemswithunknownnonlinearitiesthatmightnotbelinearlyparameterized.Themajoradvantageofthepresentworkwastorelaxtherequirementofmatchingcondition,I.e.,theunknownnonlinearitiesappearonthesameequationasthecontrolinputinastate-spacerepresentation,whichwasrequiredinmostoftheavailableneuralnetworkcontrollers.Bysynthesizingastate-feedbackneuralcontrollertonaketheclosed-loopsystemdissipativewithrespecttoaquadraticsupplyrate,thedevelopedcontrolschemeguaranteesthattheL2-gainofcontrolledsystemwaslessthanorequaltoaprescribedlevel.Andthen,itisshownthattheoutputtrackingerrorisuniformlyultimatebounded.Thedesignschemeisillustratedusinganumericalsimulation.

  • 标签: 非线性系统 自适应控制 神经网络 损耗理论