学科分类
/ 1
16 个结果
  • 简介:Apotentialreductionalgorithmisproposedforoptimizationofaconvexfunctionsubjecttolinearconstraints.Ateachstepofthealgorithm,asystemoflinearequationsissolvedtogetasearchdirectionandtheArmijo'sruleisusedtodetermineastepsize.Itisprovedthatthealgorithmisgloballyconvergent.Computationalresultsarereported.

  • 标签: 线性约束凸规划 位势归约 运算法则 线性方程
  • 简介:ItisprovedthatalinearlyrecursivesequenceofnindiceaoverfieldF(n≥1)isautorntaticallyaproductofnlioearlyrecurplvesequenceaof1-lndexoverFbythetheoryofHopfalgebras.Bytheway,thecorrespondencebetweenthesetoflinearlyrecursivesequenoesof1-indexandF[X]^0isgeneralisedtothecaseofn-index.

  • 标签: 霍普夫代数分支 线性回归序列 回归相关 上代数
  • 简介:Inthispaper,wepresentanextensivestudyofthelinearlyforcedisotropicturbulence.Byusinganalyticalmethod,weidentifytwoparametricchoices,ofwhichtheyseemtobenewasfarasourknowledgegoes.WeprovethattheunderlyingnonlineardynamicalsystemforlinearlyforcedisotropicturbulenceisthegeneralcaseofacubicLienardequationwithlineardamping.WealsodiscussaFokker–Planckapproachtothisnewdynamicalsystem,whichisbistableandexhibitstwoasymmetricandasymptoticallystablestationaryprobabilitydensities.

  • 标签: 非线性动力系统 各向同性湍流 双稳特性 LIENARD方程 线性阻尼 概率密度
  • 简介:Inthispaper,weprovideanewgeneralizedgradientprojectionalgorithmfornonlinearprogrammingproblemswithlinearconstraints.Thisalgorithmhassimplestructureandisverypracticalandstable.Undertheweakerassumptions,wehaveprovedtheglobalconvergenceofouralgorithm.

  • 标签: 广义性 倾斜投影 运算法则 线性约束 非线性规划
  • 简介:Thispaperinvestigatesthemaximumentropyrestorationofblurredbinaryimage.Inconcerningwiththebinarypropertyofimage,anewmaximumentropyrestorationmethodwithbinaryconstraintisproposed.Thepropertiesofexistenceanduniquenessofsolutionarediscussed.Theproblemofmaximumofentropywithtwoconstraintsissolvedandthecorre-spondingalgorithmisgiven.Inthispaper,themaximumboundedentropyprincipleisemployedconcerningthepriorknowledgeofbinaryimage,andthemaximumboundedentropyrestora-tionmethodwithbinaryconstraintisputforward.Theproposesmethods,Wienerfilter(WF)restorationmethodandmaximumentropyrestorationmethodarecompared.Theexperimen-talresultsshowthatthemaximumentropyrestorationmethodandmaximumboundedentropyrestorationmethodwithbinaryconstraintcanimprovethequalityofrestoredimage.

  • 标签: IMAGE RESTORATION Binary IMAGE MAXIMUM ENTROPY
  • 简介:Bymeansofreasonableassumptionandmathematicalderivation,atheoreticexpressionofflowrateforasinglefracturewithlinearlyvaryingwidthwasobtained.Themathematicalderivationwasbasedonthecubiclawandthenewtheoreticexpressionwasanextentionoftraditionalparallelplatemodel.Thisstudymayhelptoanalyzeseepageinfracturedrockmass.

  • 标签: 线性变化 宽度 流量 单裂隙 数学推导 平行板模型
  • 简介:Nonlinearstochasticoptimalcontrolproblemsarefundamentalincontroltheory.Ageneralclassofsuchproblemscanbereducedtocomputingtheprincipaleigenfunctionofalinearoperator.Here,wedescribeanewmethodforfindingthiseigenfunctionusingamovingleast-squaresfunctionapproximation.Weuseefficientiterativesolversthatdonotrequirematrixfactorization,therebyallowingustohandlelargenumbersofbasisfunctions.Thebasesareevaluatedatcollocationstatesthatchangeoveriterati...

  • 标签: 随机的最佳的控制 贝尔曼方程
  • 简介:Inthispaper,weproposeandexperimentallyinvestigatealinearlypolarizednarrow-linewidthrandomfiberlaser(RFL)operatingat1080nmandboosttheoutputpowertokilowattlevelwithnear-diffraction-limitedbeamqualityusingamasteroscillationpoweramplifier.TheRFLbasedonahalf-openedcavity,whichiscomposedofalinearlypolarizednarrow-linewidthfiberBragggratinganda500mpieceofpolarization-maintainedGe-dopedfiber,generatesa0.71Wseedlaserwithan88pmfullwidthathalf-maximum(FWHM)linewidthanda22.5dBpolarizationextinctionratio(PER)forpowerscaling.Atwo-stagefiberamplifierenhancestheseedlasertothemaximal1.01kWwithaPERvalueof17dBandabeamqualityofM_x~2=1.15andM_y~2=1.13.NostimulatedBrillouinscatteringeffectisobservedattheultimatepowerlevel,andtheFWHMlinewidthoftheamplifiedrandomlaserbroadenslinearlyasafunctionoftheoutputpowerwithacoefficientofabout0.1237pm∕W.Tothebestofourknowledge,thisisthefirstdemonstrationofalinearlypolarizednarrow-linewidthRFLwithevenkilowatt-levelnear-diffraction-limitedoutput,andfurtherperformancescalingisongoing.

  • 标签:
  • 简介:Wereportonthehigh-poweramplificationofa1064nmlinearlypolarizedlaserinanall-fiberpolarizationmaintainedmasteroscillatorpoweramplifier,whichcanoperateatanoutputpowerlevelof1.3kW.Thebeamquality(M~2)wasmeasuredtobe<1.2atfullpoweroperation.Thepolarizationextinctionrateofthefiberamplifierwasmeasuredtobeabove94%beforemodeinstabilities(MIs)setin,whichreducedtoabout90%aftertheonsetofMI.ThepowerscalingcapabilityofstrategiesforsuppressingMIisanalyzedbasedonasemianalyticalmodel,thetheoreticalresultsofwhichagreewiththeexperimentalresults.ItshowsthatmitigatingMIbycoilingthegainfiberisaneffectiveandpracticalmethodinstandarddouble-claddinglargemodeareafiber,and,bytightcoilingofthegainfibertotheradiusof5.5cm,theMIthresholdcanbeincreasedtothreetimeshigherthanthatwithoutcoilingorloosecoiling.Experimentalstudieshavebeencarriedouttoverifytheidea,whichhasprovedthatMIwassuppressedsuccessfullyintheamplifierbypropercoiling.

  • 标签: