简介:GivenacompletegraphwithvertexsetXandsubsetsX1,X2,...,Xn,theproblemoffindingasubgraphGwithminimumnumberofedgessuchthatforeveryi=1,2,...,n,GcontainsaspanningtreeonXi,arisesinthedesignofvaccumsystems.Ingeneral,thisproblemisNP-completeanditisprovedthatforn=2and3thisproblemispolynomial-timesolvable.Inthispaper,weprovethatforn=4,theproblemisalsopolynomial-tlmesolvableandgiveamethodtoconstructthecorrespondinggraph.
简介:AnewSQPtypefeasiblemethodforinequalityconstrainedoptimizationispresented,itisacombinationofamasteralgorithmandanauxiliaryalgorithmwhichistakenonlyinfiniteiterations.Thedirectionsofthemasteralgorithmaregeneratedbyonlyonequadraticprogramming,anditsstep-sizeisalwaysone,thedirectionsoftheauxiliaryalgorithmarenew'secondorder'feasibledescent.Undersuitableassumptions,thealgorithmisprovedtopossessglobalandstrongconvergence,superlinearandquadraticconvergence.
简介:Basedonanewefficientidentificationtechniqueofactiveconstraintsintroducedinthispaper,anewsequentialsystemsoflinearequations(SSLE)algorithmgeneratingfeasibleiteratesisproposedforsolvingnonlinearoptimizationproblemswithinequalityconstraints.Inthispaper,weintroduceanewtechniqueforconstructingthesystemoflinearequations,whichrecurstoaperturbationforthegradientsoftheconstraintfunctions.Ateachiterationofthenewalgorithm,afeasibledescentdirectionisobtainedbysolvingonlyonesystemoflinearequationswithoutdoingconvexcombination.ToensuretheglobalconvergenceandavoidtheMaratoseffect,thealgorithmneedstosolvetwoadditionalreducedsystemsoflinearequationswiththesamecoefficientmatrixafterfiniteiterations.Theproposedalgorithmisprovedtobegloballyandsuperlinearlyconvergentundersomemildconditions.WhatdistinguishesthisalgorithmfromthepreviousfeasibleSSLEalgorithmsisthatanimprovingdirectionisobtainedeasilyandthecomputationcostofgeneratinganewiterateisreduced.Finally,apreliminaryimplementationhasbeentested.