简介:Thisletterreportsastudyofahybridburstassemblyandahybridburstlossrecoveryscheme(delay-basedburstassemblyandhybridlossrecovery(DBAHLR))whichselectivelyemploysproactiveorreactivelossrecoverytechniquesdependingontheclassificationoftrafficintoshorttermandlongterm,respectively.TrafficpredictionandsegregationofopticalburstswitchingnetworkflowsintothelongtermandshorttermareconductedbasedonpredictedlinkholdingtimesusingthehiddenMarkovmodel(HMM).ThehybridburstassemblyimplementedinDBAHLRusesaconsecutiveaverage-basedburstassemblytohandlejitterreductionnecessaryinreal-timeapplications,withvariationsinburstsizesduetothenon-monotonicnatureoftheaveragedelayhandledbyadditionalburstlengththresholding.ThisdynamichybridapproachbasedonHMMpredictionprovidesoverallalowerblockingprobabilityanddelayandmorethroughputwhencomparedwithforwardsegmentredundancymechanismorpurelyHMMprediction-basedadaptiveburstsizingandwavelengthallocation(HMM-TP).
简介:Calibratingasmallfieldcameraisachallengingtaskbecausethetraditionaltargetwithvisiblefeaturepointsthatfitthelimitedspaceisdifficultandcostlytomanufacture.Wedemonstrateanovelcombinedtargetusedincameracalibration.Thetangentpointssuppliedbyonecirclelocatedatthecenterofasquareareusedasinvisiblefeatures,andtheperspectiveprojectioninvarianceisproved.Bothvisibleandinvisiblefeaturesextractedbytheproposedfeatureextractionalgorithmareusedtosolvethecalibration.Thetargetsuppliesasufficientnumberoffeaturepointstosatisfytherequirementsofcalibrationwithinalimitedspace.Experimentsshowthattheapproachcanachievehighrobustnessandconsiderableaccuracy.Thisapproachhaspotentialforcomputervisionapplicationsparticularlyinsmallfieldsofview.
简介:Anovelphotonic-assistedapproachtomicrowavefrequencymeasurementisproposedandexperimentallydemonstrated.Theproposedschemeisbasedonthefrequency-to-powermappingwithdifferenttransmissionresponses.Apolarizerisusedinoneoutputbranchofaphasemodulatortosimultaneouslyimplementphasemodulationandintensitymodulation.OwingtothecomplementarynatureofthetransmissionresponsesandtheMach-Zehnderinterferometers(MZIs),thisschemetheoreticallyprovideshighresolutionandtunablemeasurementrange.Themeasurementerrorsintheexperimentalresultscanbekeptwithin0.2GHzoverafrequencyrangefrom0.1to5.3GHz.