简介：Timesynchronizationtechniques,especiallyonthepulsepersecond(PPS)temporalbasis,haveattractedgrowingresearchinterestsinrecentyears.Inthispaper,wehaveproposedandexperimentallydemonstratedahigh-precisiontwo-waytimetransfer(TWTT)systemtorealizelong-distancedisseminationof1PPSsignalgeneratedbyahydrogenmaser.Adense-wavelength-division-multiplexing(DWDM)systemandbi-directionalerbium-dopedfiberamplifiers(Bi-EDFAs)havealsobeenadoptedtosuppresstheimpactofRayleighbackscatteringandoptimizethesignaltonoiseratio(SNR)aswell.Wehavetheoreticallyanalyzedthesystematicdelayindetail.Theultimaterootmeansquare(RMS)variationoftimesynchronizationaccuracyissub-26psandthetimedeviationcanbereducedtoaslowas1.2psat100sand0.253psat12000s,respectively.

简介：在双重的femtocell网络，中央macrocell在通用频率复用模式最好是有很多更短的范围femtocell热点的underlaid，它是。这种新网络体系结构引起迫切挑战到干扰管理和收音机资源分配的计划。由这些挑战激发了，三贡献在这份报纸被做：1)为多重存取(OFDMA)downlink基于的直角的频率分割的一个新奇联合子通道和力量分配问题femtocells在最小化每个Femto基础车站的散发的干扰的前提上被提出。2)伪移交基于安排交换方法被建议交换合作级，并且因此避免碰撞干扰的信息和跨级的信息。3)力量控制和子通道的一个反复的计划被建议在贡献1解决提出的问题)，它是一个NP完全的问题。通过有四个另外的计划的模拟和比较，在减少干扰并且改进光谱效率的更好的性能被建议计划完成。

简介：Classicalnetworkreliabilityproblemsassumebothnetworksandcomponentshaveonlybinarystates,fullyworkingorfullyfailedstates.Butmanyactualnetworksaremulti-state,suchascommunicationnetworksandtransportationnetworks.Thenodesandarcsinthenetworksmaybeinintermediatestateswhicharenotfullyworkingeitherfullyfailed.Asimulationapproachforcomputingthetwo-terminalreliabilityofamulti-statenetworkisdescribed.Two-terminalreliabilityisdefinedastheprobabilitythatdunitsofdemandcanbesuppliedfromthesourcetosinknodesunderthetimethresholdT.Thecapacitiesofarcsmaybeinastochasticstatefollowinganydiscreteorcontinuousdistribution.Thetransmissiontimeofeacharcisalsonotafixednumberbutstochasticaccordingtoitscurrentcapacityanddemand.Tosolvethisproblem,acapacitatedstochasticcolouredPetrinetisproposedformodellingthesystembehaviour.Placesandtransitionsrespectivelystandforthenodesandarcsofanetwork.Capacitatedtransitionandself-modifiedtokencolourwithrouteinformationaredefinedtodescribethemulti-statenetwork.Bythesimulation,thetwo-terminalreliabilityandnodeimportancecanbeestimatedandtheoptimalroutewhosereliabilityishighestcanalsobegiven.Finally,twoexamplesofdifferentkindsofmultistatenetworksaregiven.

简介：:Twonovelpoly[(3-alkyhhiophene-2,5-diyl)-(benzylidenequinomethane-2,5-diyl)s]derivatives,poly[(3-butylthiophene-2,5-diyl)-(p-N,N-dimethylamino)benzylidenequinomethane-2,5-diyl)](PBTDMABQ)andpoly[-(3-octylthiophene2,5-diyl)-(p-N,N-dimethylamino)benzylidenequinomethane-2,5-diyl)](POTDMABQ),weresynthesized.Thebandgapsofthetwopolymersarecalculatedas1.75eVforPBTDMABQand1.69eVforPOTDMABQ,respectively.Thehomogenousfilmsofthetwopolymerswerepreparedandtheirthird-ordernonlinearopticalpropertieswerestudiedbythebackwarddegeneratefour-wavemixingat532nm.Byusingtherelativemeasurementtechnique,thethird-ordernonlinearopticalsusceptibilitiesofPBTDMABQandPOTDMABQarecalculatedas5.62×10^-9and1.22×10^-8ESU,respectively.Itisfoundthatsubstitutedalkygroupshavestrongeffectsonthebandgapandnonlinearopticalpropertiesofthetwopolymers.Therelativelybigthird-ordernonlinearopticalsusceptibilitiesandsmallbandgapofPOTDMABQresultedmainlyfromthelongeralkylwithstrongelectron-donatingabilitycanenhancethedelocationdegreeofconjugatedπelectronics.

简介：纵观Kre11的产品线，都是单体(主机电源一体化)机器居多，最新推出的Evolution系列可谓聚Kre1125年经验之精华，正如其名，Evolution系列的出现，算得上是Kre11放大器的革命。