简介:摘要尽管从认知无线电范式的提出已经经历了十几年了,在这些年里研究主要集中于物理层和媒体访问的问题上,而最近的一些研究才针对认知网络的路由问题。本文将移动认知无线电和AdHoc网络的反应式路由相结合解决了这个问题。通过设计了一个反应式路由协议来达到此目的。
简介:Thispaperconsidersadiscrete-timeGeo/G/1queueinamulti-phaseserviceenvironment,wherethesystemissubjecttodisastrousbreakdowns,causingallpresentcustomerstoleavethesystemsimultaneously.Atafailureepoch,theserverabandonstheserviceandthesystemundergoesarepairperiod.Afterthesystemisrepaired,itjumpstooperativephaseiwithprobabilityqi,i=1,2···,n.Usingthesupplementaryvariabletechnique,weobtainthedistributionforthestationaryqueuelengthatthearbitraryepoch,whicharethenusedforthecomputationofotherperformancemeasures.Inaddition,wederivetheexpectedlengthofacycletime,thegeneratingfunctionofthesojourntimeofanarbitrarycustomer,andthegeneratingfunctionoftheserver’sworkingtimeinacycle.Wealsogivetherelationshipbetweenthediscrete-timequeueingsystemtoitscontinuous-timecounterpart.Finally,someexamplesandnumericalresultsarepresented.