简介:ThebasicprincipleofintervalarithmeticandthebasicalgorithmoftheintervalNewtonmethodsareintroduced.Theprototypealgorithmcannotfindanyzeroinanintervalthathaszerosometimes,thatis,itisinstable.Sotheprototyperelaxationprocedureisimprovedinthispaper.Additionally,animmediatetestoftheexistenceofasolutionfollowingbranch-and-boundisproposed,whichavoidsunwantedcomputationsinthoseintervalsthathavenosolution.ThenumericalresultsdemonstratthattheimprovedintervalNewtonmethodissuperiortoprototypealgorithmintermsofsolutionquality,stabilityandconvergentspeed.
简介:Withtheemergenceoflocation-basedapplicationsinvariousfields,thehigheraccuracyofpositioningisdemanded.Byutilizingthetimedifferencesofarrival(TDOAs)andgainratiosofarrival(GROAs),anefficientalgorithmforestimatingthepositionisproposed,whichexploitstheBroyden-Fletcher-Goldfarb-Shanno(BFGS)quasi-Newtonmethodtosolvenonlinearequationsatthesourcelocationundertheadditivemeasurementerror.Althoughtheaccuracyoftwo-stepweighted-least-square(WLS)methodbasedonTDOAsandGROAsisveryhigh,thismethodhasahighcomputationalcomplexity.Whiletheproposedapproachcanachievethesameaccuracyandbiaswiththelowercomputationalcomplexitywhenthesignal-to-noiseratio(SNR)ishigh,especiallyitcanachievebetteraccuracyandsmallerbiasatalowerSNR.Theproposedalgorithmcanbeappliedtotheactualenvironmentduetoitsreal-timepropertyandgoodrobustperformance.Simulationresultsshowthatwithagoodinitialguesstobeginwith,theproposedestimatorconvergestothetruesolutionandachievestheCramer-Raolowerbound(CRLB)accuracyforbothnear-fieldandfar-fieldsources.
简介:WeprovideconvergenceresultsanderrorestimatesforNewton-likemethodsingeneralizedBanachspaces.TheideaofageneralizednormisusedwhichisdefinedtobeamapfromalinearspaceintoapartiallyorderedBanachspace.Convergenceresultsanderrorestimatesareimprovedcomparedwiththerealnormtheory.
简介:Nanowireshavebeenprovedtobeexcellentcandidatesforfuturenanodevicesfortheiradvantagesofbeingthesmallestchargecarrier,enablingabundantchoiceofmaterials,andrelatedsize,surfaceandquantumeffects.Nanowiresthusplayimportantroletounderstandthephysicalphenomenabetweenmacro-scaleNewtonworldandthemicro-scalequantummechanicalworld.Ourgroupisamongthefewpioneersinearly1998'sindevelopingmethodsforsynthesisofsiliconnanowires,andextendingthenanowiresynt...