简介：ＯＮＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＹＯＦＣＯＮＳＴＲＡＩＮＴＷｅｉＹａｎｇ（韦杨）；ＬｉａｎｇＬｉｆｕ（梁立孚）；ＬｉａｎｇＺｈｏｎｇｗｅｉ（梁忠伟）（ＲｅｃｅｉｖｅｄＳｅｐ．６，１９９４；ＣｏｍｍｕｎｉｃａｔｅｄｂｙＣｈｉｅｎＷｅｉｚａｎｇ）Ａ...

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简介：Singularityanalysisinanimportantsubjectofthegeometricconstraintsatisfactionproblem.Inthispaper,threekindsofsingularitiesaredescribedandcorrespondingidentifcationmethodsarepresentedforbothunder0constrainedsystemsandover-constrainedsystems,Anotherspecialbutcommonsingularityforunder-constrainedgeometricsystems,pseudo-singularity,isanalyzed.Pseudo-singularityiscausedbyavarietyofconstraintmathchingofunder-constrainedsystemsandcanberemovedbyimprovingconstraintdistribution.Toavoidpseudo-singularityanddecideredundantconstraintsadaptively,adifferentiaitonalgorithmisproposedinthepaper.Itscorrctnessandeffciencyhavebeenvalidatedthroughitspracticalapplicationsina2D/3DgeometricconstraintsolverCBA.

简介：ByusingMoore-Penrosegeneralizedinverseandthegeneralsingularvaluedecompositionofmatrices,thispaperestablishesthenecessaryandsufficientconditionsfortheexistenceofandtheexpressionsforthecentrosymmetricsolutionswithasubmatrixconstraintofmatrixinverseproblemAX=B.Inaddition,inthesolutionsetofcorrespondingproblem,theexpressionoftheoptimalapproximationsolutiontoagivenmatrixisderived.

简介：TheVaR,anewappearingfinancialrisk-managetool,havebeenappliedwidely.ManyfinancialsetupshaveaccustomedtomeasuretheriskofaportfoliowiththeVaR.SoitisverynecessarytodiscusstheportfoliochoiceproblemundertheVaRconstraint.Inthispaper,bysettingandsolvingtheportfoliochoicemodelundertheVaRconstraint,weillustratethattheuseoftheVaRconstraintreducesthearrayofchoicetoamoremanageablerange.TheprobabilityoftragetVaR,therefore,canbethoughtofasarisktoleranceassessmenttool(whencoupledwithanothermeasureofrisk).

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简介：FortheARMAXsystemwithunknowncoefficientstheoptimaladaptivecontrolisdesignedsothatthefollowingrequirementsaremetsimultaneously:1)thetransferfunctionfromareferencesignaltothesystemoutputintheclosedloopequalsaprescribedrationalfunction;2)undertheconstraintmentionedin1)aquadraticlossfunctionisminimized;3)theparameterestimateisstronglyconsistent.

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简介：Inthetest-fieldcalibration,multi-azimuthstereoimagepairsareproducedoftheoutdoorlargecontrol-fieldbythestereo-visionsystemundercali-bration.Whileintheanalyticalprocessing,therelationshipbetweenimagepairsisadoptedasaconstraintcondition,whichensuresthestabilityandqualityofthecalibrationresults.Thispaperintroducesthedeductionprocessoftheconstraintconditions.

简介：Thispaperdealswiththeintegrabilityofafinite-dimensionalHamiltoniansystemlinkedwiththegeneralizedcoupledKdVhierarchy.ForthispurposetheassociatedLaxrepresentationispresentedafteranelementarycalculation.ItisshownthattheLaxrepresentationenjoysadynamicalr-matrixformulainsteadofaclassicaloneinthePoissonbracketonR2N.Consequentlytheresultingsystemisprovedtobecompletelyintegrableinviewofitsr-matrixstructure.

简介：TherearesomeadjustableparameterswhichdirecdyinfluencetheperformanceandstabilityofParticleSwarmOp-ttimizationalgorithm.Inthispaper,stabilitiesofPSOwithconstantparametersandtime-varyingparametersareanalyzedwithoutLipschitzconstraint.Necessaryandsufficientstabilityconditionsforaccelerationfactorψandinertiaweightwarepresented.Exper-imentsonbenchmarkfunctionsshowthegoodperfomanceofPSOsatisfyingthestabilitycondition,evenwithoutLipschitzcon-straint.Andtheinertiaweightwvalueisenhancedto(-1,1).

简介：Inacomposite-stepapproach,astepskiscomputedasthesumoftwocomponentsvkandhk.Thenormalcomponentvk,whichiscalledtheverticalstep,aimstoimprovethelinearizedfeasibility,whilethetangentialcomponenthk,whichisalsocalledhorizontalstep,concentratesonreducingamodelofthemeritfunctions.Asafiltermethod,itreducesboththeinfeasibilityandtheobjectivefunction.Thisisthesamepropertyofthesetwomethods.Inthispaper,oneconcernsthecomposite-steplikefilterapproach.Thatis,astepistangentialcomponenthkiftheinfeasibilityisreduced.Orelse,skisacompositestepcomposedofnormalcomponentVkandtangentialcomponenthk.

简介：Inthispaper,theeffectofplasticconstraintontheinitiationofductiletearsinfourdifferentshipbuildingstructuralsteelshasbeenexperimentallystudiedbymeasuringtheJ-integralandcrackopeningdisplacementCODatinitiationinthree-pointbendspecimenswithdeepandshallownotches.ExperimentalresultsofsevengroupsofdifferentstrengthalloysteelsshowthatbothδìandJìvaluesofductiletearfromtheshallowcrackspecimenswhichhavelessconstraintflowfieldaresignificantlyhigherthanthoseofdeeplynotchedspecimens.Slip-line-fieldanalysisshowsthat,forshallowcrack,thehydrostaticstressislowerthanthatfromstandarddeeplycrackedbendspecimen,whichdevelopsahighlevelofcracktipconstraint,providesalowerboundestimateoftoughness,andwillensureanundulyconservativeapproachwhenappliedtostructuraldefects,especiallyifinitiationvaluesofCODandJ-integralareused.

简介：Bifurcationswithconstraintsareopenproblemsappearedinresearchonperiodicbifurcationsofnonlineardynamicalsystems,butthepresentsingularitytheorydoesn'tcontainanyanalyticalmethodsandresultsaboutit.Asthecomplementtosingularitytheoryandthefirststeptostudyonconstrainedbifurcations,herearegiventhetransitionsetsandpersistentperturbedbifurcationdiagramsof10elementarybifurcationofcodimensionnomorethanthree.

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简介：Aclassofconstrainedsemiinfiniteminimaxproblemistransformedintoasimpleconstrainedproblem,bymeansofdiscretizationdecoraposirionandmaximumentropymethod,makinguseofsurrogateconstraint,ThepaperdealswiththeconvergenceofthisasymptoticaI-proachmethod.

简介：ThereportednewU-Pbagebysensitivehigh-resolutionionmicroprobe(SHRIMPⅡ)onzirconwasobtainedfromatuffsampleatthebasalDoushantuoFormationintheJiuqunaosection,whichsituatedatthewesternlimboftheHuanglinganticlineintheYangtzeGorgesinZigui,Hubei,SouthChina.Eighteenspotsofzirconswereanalyzedandtheyformtwoclusters:oneincludesthreespots,withaninheritedageof784+15Ma(MSWD=0.05);theotherconsistsof15spotsandgivesaweightedmean^206pb/^238Uageof628.3±5.8Ma(MSWD=0.86).ItisthefirstSHRIMPU-PbzirconageobtainednearlythebaseoftheDoushantuoFormationofEdiacaranandrepresentsamaximumageoftheDoushantuoFormationItalsoformsanageconstraintontheupperlimitageoftheNantuo(Marinoantype)glaciation.