简介:Arithmeticcodingisarelativelynewloss-lessdatacompressiontechniquethathasattractedmuchattentioninrecentyears.Weshowtheiterationofbit-levelarithmeticcodingcanbespecifiedbyacontinuousfunction.Theanalysisexpressionandsomepropertiesofthisfunctionarediscussed.Anapplicationofthefunctionisprovidedforexploringthesecurityofarithmeticcodeswhentheyareusedfordataencryption.
简介:Variousindexstructureshaverecentlybeenproposedtofacilitatehigh-dimensionalKNNqueries,amongwhichthetechniquesofapproximatevectorpresentationandone-dimensional(1D)transformationcanbreakthecurseofdimensionality.Basedonthetwotechniquesabove,anovelhigh-dimensionalindexisproposed,calledBit-codeandDistancebasedindex(BD).BDisbasedonaspecialpartitioningstrategywhichisoptimizedforhigh-dimensionaldata.Bythedefinitionsofbitcodeandtransformationfunction,ahigh-dimensionalvectorcanbefirstapproximatelyrepresentedandthentransformedintoa1Dvector,thekeymanagedbyaB+-tree.AnewKNNsearchalgorithmisalsoproposedthatexploitsthebitcodeanddistancetoprunethesearchspacemoreeffectively.ResultsofextensiveexperimentsusingbothsyntheticandrealdatademonstratedthatBDout-performstheexistingindexstructuresforKNNsearchinhigh-dimensionalspaces.
简介:Reductionofmodulatorenergyconsumptionto10fJ∕bitisessentialforthesustainabledevelopmentofcommunicationsystems.Lumpedmodulatorsmightbeaviablesolutionifinstructedbyacompletetheorysystem.Here,wepresentacompleteanalyticalelectro-opticresponsetheory,energyconsumptionanalysis,andeyediagramsonabsolutescalesforlumpedmodulators.Consequentlythespeedlimitationisunderstoodandalleviatedbysingle-driveconfiguration,andcomprehensiveknowledgeintotheenergydependenceonstructuralparameterssignificantlyreducesenergyconsumption.Theresultsshowthatsiliconmodulationenergyaslowas80.8and21.5fJ∕bitcanbeachievedat28Gbdunder50and10Ωimpedancedrivers,respectively.A50Gbdmodulationisalsoshowntobepossible.Theanalyticalmodelscanbeextendedtolumpedmodulatorsonothermaterialplatformsandofferapromisingsolutiontothecurrentchallengesofmodulationenergyreduction.
简介:Inthisreport,wepresentasimulatedresultontheion-massindependenceoftheguidedtransmission,whichisinagreementwiththepreviousexperimentalresults[1].Inordertosearchtheinuenceoftheionmassonguidedtransmission,variousspeciesofionsusedasprojectilesinsimulations.Fig.1showsthetransmissionfractionsforNe7+,Ar7+,Kr7+,andXe7+ions.Thesedatawereacquiredfortiltangleof2inenergyof7keV.Itisseenthatallofionfractionsgraduallyrisesafteratimedelay,andnallyreachstable.
简介:Asamemberof1Dnanostructuredmaterials,theferromagneticandnonmagneticmultilayernanowiresexhibittremendouspotentialapplicationsinmanyfieldsduetotheiruniquemagneticandelectricalproperties.Thebasicpropertyofmultilayernanowirearrays,suchascoercivity,iscrucialimportantforthefutureapplication.Inordertoobtainthecoercivityinformation,besidesdirectlymeasuringitthroughexperiment,theoreticalcalculationalsoprovidesausefulandfastwaytoevaluatethemultilayer’scoervicity.Fig.1(a)and(b)demonstrateasinglemultilayernanowireandnanowirearraysembodiedinamatrix,respectively.Inthiswork,byimprovingPant’smodel,wedevelopedthenewmodelandsuccessfullypredictedtherelationshipbetweenthecoercivitychangingofCu/Nimultilayernanowirearraysandstructualparameters.Fig.
简介:AlNthinfilmsirradiatedwith100MeVU,95MeVArand84MeVCionsfromtheHIRFL-SFC(HeavyIonResearchFacilityinLanzhou)wereinvestigatedbyInfraredspectraandRamanspectra.ItappearedA1(TO),A1(LO),E1(To)andE2PhononvibrationabsorptionmodetoirradiatedsamplesinFig.1.652cm??1isvibrationabsorptionpeakofAlN,withtheincreaseofirradiationdose,thevibrationabsorptionbandappearacertainbroadeningphenomena.Lightercarbonionirradiationonthevibrationabsorptionbandbroadeningoftheimpactisnotbig.670cm??1isthetransverseopticalphononabsorptionpeakoftheE1(TO),afterirradiation,thevibrationabsorptionpeakandthebroadenAl-Nkeyintoanorganicwhole.249and660cm??1istheE2(low)andE2(high)