简介:Electricaldischargemachining(EDM)process,atpresentisstillanexperienceprocess,whereinselectedparametersareoftenfarfromtheoptimum,andatthesametimeselectingoptimizationparametersiscostlyandtimeconsuming.Inthispaper,artificialneuralnetwork(ANN)andgeneticalgorithm(GA)areusedtogethertoestablishtheparameteroptimizationmodel.AnANNmodelwhichadaptsLevenberg-Marquardtalgorithmhasbeensetuptorepresenttherelationshipbetweenmaterialremovalrate(MRR)andinputparameters,andGAisusedtooptimizeparameters,sothatoptimizationresultsareobtained.Themodelisshowntobeeffective,andMRRisimprovedusingoptimizedmachiningparameters.
简介:Itisshownthatorbitalangularmomentum(OAM)isapromisingnewresourceinfutureclassicalandquantumcommunications.However,theseparationofOAMmodesisstillabigchallenge.Inthispaper,weproposeasimpleandefficientseparationmethodwitharadialvaryingphase.Inthemethod,specificradialvaryingphasesaredesignedandmodulatedfordifferentOAMmodes.Theresultantbeamisfocusedtothespotswithdifferenthorizontalandverticalpositionsafteraconvexlens,whenthecoordinatetransformation,includingtwoopticalelementswithcoordinatetransformationphaseandcorrectphase,operatesonthereceivedbeam.Thehorizontalpositionofthespotisdeterminedbythevortexphases,andtheverticalpositionofthespotisdependentontheradialvaryingphases.ThesimulationandexperimentalresultsshowthattheproposedmethodisfeasiblebothforseparationoftwoOAMmodesandseparationofthreeOAMmodes.TheproposedseparationmethodisavailableinprincipleforanyneighboringOAMmodesbecausetheradialvaryingphaseiscontrolled.Additionally,noextrainstrumentsareintroduced,andthereisnodiffractionandnarrowingprocesslimitationfortheseparation.
简介:我们在场微分照(DQ)的申请为有指数地基于Euler-Bernoulli,Timoshenko,瑞迪,和Levison的四个不同横梁理论改变僵硬的nanobeams的弄弯的分析的方法。明确的表达基于Eringen的非局部的弹性理论。新结果被介绍为指导了并且简单地支持了指导边界条件。数字结果被获得在批评弄弯负担参数上调查非局部的参数,length-to-height比率,边界条件,和不一致的参数的效果。当批评弄弯负担参数随length-to-height比率的增加增加时,批评弄弯负担随非局部的参数的增加减少,这被观察当批评弄弯负担参数随length-to-height比率的增加增加时。
简介:Theaimofthisresearchistocharacterizethedevelopmentoffatiguedamagebymeansofstress-strainhysteresis.Experimentswereconductedon14specimensmadeofcold-finishedunannealedAISI1018steel.Resultsdemonstratethatthemechanicalhysteresisloopareas,whenplottedasafunctionofthenumberofloadingcycles,showsignificantvariationsanddemonstratethethreeprincipalstagesconcerningtheprogressofthefatiguefailure—initialaccommodation,accretionofdamageandterminalfailure.ThesethreestagesoffatiguearemarkedbythetransitionsatcyclesN2andN3.ExperimentalresultsshowthatalthoughfatiguelifeNfrangesfrom2644cyclesto108992cycles,theratiosofN2/NfandN3/Nftendtobestable:N2/Nf=10.7%,N3/Nf=91.3%.
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简介:Spatialcoherenceresonanceinatwo-dimensionalneuronalnetworkinducedbyadditiveGaussiancolourednoiseandparameterdiversityisstudied.WefocusontheabilityofadditiveGaussiancolourednoiseandparameterdiversitytoextractaparticularspatialfrequency(wavenumber)ofexcitatorywavesintheexcitablemediumofthisnetwork.Weshowthatthereexistsanintermediatenoiselevelofthecolourednoiseandaparticularvalueofdiversity,whereacharacteristicspatialfrequencyofthesystemcomesforth.Hereby,itisverifiedthatspatialcoherenceresonanceoccursinthestudiedmodel.Furthermore,weshowthattheoptimalnoiseintensityforspatialcoherenceresonancedecaysexponentiallywithrespecttothenoisecorrelationtime.Someexplanationsoftheobservednonlinearphenomenaarealsopresented.
简介:在黑色基于Blandford-Znajek和磁性的联合进程的共存洞(BH)生长圆盘,为喷气力量的一个多参数模型和活跃星群的原子核(AGN)的收音机大声被学习。结果,AGN的收音机大声能被五个参数管理:(ⅰ)BH旋转,(ⅱ)变化的一个幂定律索引磁性在圆盘上删除;(ⅲ)决定圆盘的内部边的位置的一个参数,(ⅳ)到生长流动的最深处的部分的公羊压力的领带地平线上的磁场的压力的比率,并且(ⅴ)到地平线的户外Reldlines的尖速度的比率。观察两分在之间收音机大声并且收音机安静AGN被上述参数的效果很好解释。而且,我们独立关于每个参数讨论AGN的收音机大声的衍生物。另外,AGN的收音机大声上的螺丝钉不稳定性的效果被讨论。
简介:Emission Temperatures from Populations of Particle Unstable States as a Function of Impact ParameterEmissionTemperaturesfromP...
简介:Asetofnewgasdynamicfunctionswithvaryingspecificheatarederiveoforthefirsttime.Anoriginalanalyticalsolutionofnormalshockwavesisowrkedouttherewith.Thissolutionisthereafterfurtherimprovedbynotinvolvingtotaltemperature,Illustrativeexamplesofcomparisonaregiven,includingalsosomeapproximatesolutionstoshowtheordersoftheirerrors.