简介:Weexperimentallydemonstratea16×16reconfigurablynonblockingopticalswitchfabricusingaBenesarchitecture.Theswitchfabricconsistsof562×2Mach–Zehnderinterferometerbasedelementaryswitches,witheachintegratedwithapairofwaveguidemicroheaters.Theaverageon-chipinsertionlossis~5.2dBforbothofthe'all-cross'andthe'all-bar'states,withalossvariationof1dBoverallroutingpaths.Thecrosstalkforallswitchingstatesisbetterthan-30dB.Theswitchingtimeoftheswitchelementisabout22μs.Theswitchingfunctionalityisverifiedbytransmissionofa40Gb∕squadraturephase-shiftkeyingopticalsignal.
简介:ThepresolarSiCgrains[1]carrytheoriginalstellarnucleosynthesissignature.Theirisotopicanomaliescomparedtothesunarethestrongconstrainsinthesupernovae(SN)modelcalculations.The15N-excessinsomeSiC-ABgrains(12C/13C<10and14N/15N<272)isoneofthechallengesofcore-collapsesupernovae(CCSNe)models[2].Recently,PignataripointedoutthattheentrainmentofH-richmaterialintotheHeshellbeforetheSNexplosionallowsthecoproductionof13C,15Nand26Al,whichprovidesanewproductionscenarioforSiC-ABgrains[2].IntheHeshellnucleosynthesis,the13Cisproducedthrough12C(p,γ)13N(β+γ)13Creaction.The14Nissynthesizedthrough13N(n,γ)and13C(p,γ)reactions.
简介:Inthispaper,withPoincare’sformalism,andanindirectmethod,thecanonicalformsofthegeneralizedequationsofmotionduetoNielsenandCenovofaholonomicdynamicalsysteminthevelocity-phasespaceandtheacenleration-phasespaceareobtainedintermsofthePoincareparameters.
简介:AbinitiomolecularorbitalcalculationsofdoublynegativechargedB16H162-(D2)andneutralB16H16(Td)havebeendoneattheHF/6-31Glevel.TheyarepredictedtobechemicallyandkineticallystablebyvibrationalanalysesontheirrespectiveenergyhypersurfaceoftheHF/6-31Glevel.ThegeometricalstructureofthespeciesB16H1622-(D2)wasdiscussed.
简介:在这份报纸,在范围的稳定的homotopy组的homotopy元素的一个新家庭由n2m5and3s代表了
简介:Weproveseveralinequaliesforsymmetricpostivesemidefinite,generalMmatricesandinverseM-matriceswhicharegeneralizationoftheclassicalOppenheim'sInequalityforsymmetricpositivesemidefinitematrices.
简介:TheauthorfirstreviewstheclassicalKorninequalityanditsproof.FollowingrecentworksofS.Kesavan,P.Ciarlet,Jr.,andtheauthor,itisshownhowtheKorninequalitycanberecoveredbyanentirelydifferentproof.ThisnewproofhingesonappropriateweakversionsoftheclassicalPoincar'eandSaint-Venantlemma.Infine,bothproofsessentiallydependonacruciallemmaofJ.L.Lions,recalledatthebeginningofthispaper.
简介:TheextendedcanonicalNoetheridentitiesandcanonicalfirstNoethertheoremderivedfromanextendedactioninphasespaceforasystemwithasingularLagrangianareformulated.UsingthesecanonicalNoetheridentities,itcanbeshownthattheconstraintmultipliersconnectedwiththefirst-classconstraintsmaynotbeindependent,soaquerytoaconjectureofDiracispresented.BasedonthesymmetrypropertiesoftheconstrainedHamiltoniansysteminphasespace,acounterexampletoaconjectureofDiracisgiventoshowthatDirac'sconjecturefailsinsuchasystem.WepresenthereadifferentwayratherthanCawley'sexamplesandother'sonesinthatthereisnolinearizationofconstraintsintheproblem.Thisexamplehasafeaturethatneithertheprimaryfirst-classconstraintsnorsecondaryfirst-classconstraintsaregeneratorsofthegaugetransformation.