简介：In4-strokeinternalcombustionengines,air-fuelratiocontrolisachallengingtaskduetotherapidchangesofenginethrottle,especiallyduringtransientoperation.Toimprovethetransientperformance,managingthecycle-to-cycletransientbehaviorofthemassoftheair,thefuelandtheburntgasisakeyissueduetotheimbalanceofcycliccombustionprocess.Thispaperaddressthemodel-basedestimationandcontrolproblemforcyclicair-fuelratioofspark-ignitionengines.Adiscrete-timemodelofair-fuelratioisproposed,whichrepresentsthecycle-to-cycletransientbehaviorofin-cylinderstatevariablesundertheassumptionsofcyclicmeasurabilityofthetotalin-cylinderchargemass,combustionefficiencyandtheresidualgasfraction.Withthemodel,aKalmanfilter-basedair-fuelratioestimationalgorithmisproposedthatenableustoperformafeedbackcontrolofair-fuelratiowithoutusinglambdasensor.Finally,experimentalvalidationresultisdemonstratedtoshowtheeffectivenessofproposedestimationandcontrolschemethatisconductedonafull-scaledgasolineenginetestbench.

简介：在2008年的MacWorld大会上,苹果公司的CEO斯蒂夫·乔布斯带着一个黄色的牛皮纸信封登场,在众人疑惑不解的目光中,他慢慢从信封内掏出了一台笔记本——MacBookAir,一时之间全场震撼,苹果的创意再次挑战了人们的想象力极限。

简介：Thispaperpresentsacoupledmagnetic-circuitmethodforcomputingthemagneticforceofair-corereactorundershort-timecurrent.Thecurrentandthemagneticfluxdensityarecomputedfirstandthenthemagneticforceisobtained.Thus,thedynamicstabilityperformanceofair-corereactorcanbeanalyzedatthedesignstagetoreduceexperimentalcostandshortenthelead-timeofproductdevelopment.

简介：经由为呼吸空气的极超音速的车辆(ABHV)的名字的轨道linearization的一条变化时间的控制法律模型被使用。可行指导命令信号连续剧被非线性的动态逆(NDI)产生在空气动力学的效果和推进系统之间的方法考虑相互作用。Multiple-time-scale连续变化时间的控制，它满足要求与精确，柔韧，并且decoupled面对为无常和外部骚乱建模追踪命令的轨道和尖率侧面被使用。为有为无常，风阵风，和测量噪音建模的一个ABHV模型的模拟被介绍表明这个建议方法的能力和可靠性。

简介：Theproblemofair-fuelratio(AFR)controloftheportinjectionsparkignition(SI)engineisstillofconsiderableimportancebecauseofstringentdemandsonemissioncontrol.Inthispaper,thestaticAFRcalculationmodelbasedonin-cylinderpressuredataandontheadaptiveAFRcontrolstrategyispresented.Themodelutilisestheintakemanifoldpressure,enginespeed,totalheatrelease,andtherapidburnangle,asinputvariablesfortheAFRcomputation.Thecombustionparameters,totalheatrelease,andrapidburnangle,arecalculatedfromin-cylinderpressuredata.ThisproposedAFRmodelcanbeappliedtothevirtuallambdasensorforthefeedbackcontrolsystem.Inpracticalapplications,simpleadaptivecontrol(SAC)isappliedinconjunctionwiththeAFRmodelforport-injectedfuelcontrol.TheexperimentalresultsshowthattheproposedmodelcanestimatetheAFR,andtheaccuracyoftheestimatedvalueisapplicabletothefeedbackcontrolsystem.Additionally,theadaptivecontrollerwiththeAFRmodelcanbeappliedtoregulatetheAFRoftheportinjectionSIengine.

简介：用“一直被模仿，从未被超越”这句话来形容APPle旗下的产品再合适不过了，从手机、平板电脑到笔记本，Apple旗下的产品往往很容易成为市场的风向标。自2008年初推出13.3英寸MacbookAir让消费者实实在在领略了一番“如空气般的轻薄”，并推动13.3英寸规格笔记本成为笔记本市场主流型号后，Apple于今年第四季度再次推出新一代MacbookAir产品，将11.6英寸这个全新的尺寸引入MacbookAir产品线中。