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简介:利用TCAD仿真技术,研究了电离总剂量辐射陷阱电荷对0.18μmN沟道MOSFET转移特性的影响.构建了0.18μmN沟道MOSFET的三维仿真结构,获得了在电离总剂量(totalionizingdose,TID)效应影响下,负栅压偏置时器件中电流密度的分布情况.分析了器件浅槽隔离层(shallowtrenchisolation,STI)中氧化物陷阱电荷和界面态陷阱电荷对器件泄漏电流的影响.仿真计算了N-MOSFET的转移特性,仿真结果与辐照试验结果受辐照影响的趋势基本一致,为深亚微米MOS器件的总剂量辐射效应的损伤机制提供了一种分析手段.
简介:Atheoreticaldesignispresentedfora1×Mwavelength-selectiveswitch(WSS)thatroutesanyoneofNincomingwavelengthsignalstoanyoneofMoutputports.Thisplanaron-chipdevicecomprisesofa1×Ndemultiplexer,agroupofNswitching'trees'actuatedbyelectro-opticalorthermo-opticalmeans,andanM-foldsetofN×1multiplexers.Treesutilize1×2switches.TheWSSinsertionlossisproportionalto(log2(M+N+1))Alongwithcrosstalkfromtrees,crosstalkispresentateachcross-illuminatedwaveguideintersectionwithintheWSS,andthereareatmostN-1suchcrossingsperpath.TheselossandcrosstalkpropertieswilllikelyplaceapracticallimitofN=M=16upontheWSSsize.Byconstrainingthe1×2switchingenergyto1fJ∕bit,wefindthatresonant,narrowband1×2switchesarerequired.The1×2devicesproposedherearenanobeamMach–Zehndersandasymmetriccontra-directionalcouplerswithgratingassistance.
简介:<正>Inthefifties.Calderonestablishedaformalrelationbetweensvmbolandkerneldistribu-tion,butitisdifficulttoestablishanintrinsicrelation.TheCalderon-Zygmund(C-Z)schoolstudiedrheC-Zoperators,andHormander.KohnandNirenberg,etal.studiedthesymbolicoperators.HereweapplyarefinementoftheLittlewood-Paley(L-P)decomposition,analyseundernewwaveletbases.tocharacterizebothsymbolicoperatorsspacesOpS1,δmandkerneldistributionsspaceswithotherspacescomposedofsomeahnostdiagonalmatrices.thengetanisometricbetweenOpS1,δmandkerneldistri-butionspaces
简介:主反射镜的口径大小与结构形式在极大程度上决定了空间望远镜的技术难度与经济成本。为了实现更高的空间分辨率与更强的信息收集能力,各国研制的空间望远镜主反射镜的口径朝着越来越大的趋势发展,从“哈勃空间望远镜”(HST)的2.4m,到“新世界观测者空间望远镜”(NWO)的4m,甚至到“先进技术大口径空间望远镜”(ATLAST)的8m,无不体现了对超大口径空间观测能力的追求。而单块式主镜凭借其支撑技术的可靠性与经济性,正成为超大口径空间望远镜的首选。通过对国外研制的超大口径空间望远镜的论述与分析,探讨了目前空间望远镜中超大口径主反射镜的关键技术与发展方向。针对目前国内运载能力与光学制造加工能力的极限,提出了建造基于3.5m口径主镜的空间望远镜设想。
简介:Amolybdenumdisulfide(MoS2)saturableabsorberwasfabricatedbythermallydecomposingtheammoniumthiomolybdate.ByusingtheMoS2absorber,acompactdiode-pumpedpassivelyQ-switchedTm:GdVO4laserhasbeendemonstrated.AstableQ-switchedlaserwithrepetitionratesfrom25.58to48.09kHzwasachieved.Maximumaverageoutputpowerwas100mWwiththeshortestpulsedurationof0.8μs.Maximumpulseenergyis2.08μJatcenterof1902nm.
简介:在一类新的G-凸度量空间中建立了一类新的KKM定理,统一、改进和发展了文献中的相应结果.作为应用,得到了几个新的匹配定理和不动点定理.
简介:本文讨论了强G-半预不变凸函数,它是强预不变凸函数与强G-预不变凸函数的真推广.首先,举例说明了强G-半预不变凸函数的存在性;然后,借助集合稠密性原理,获得了强G-半预不变凸函数的一个充要条件;最后,得到强G-半预不变凸函数在一定假设(在闭半连通集上)下的下确界就是函数在此集合上的最小值,所得结果推广并改进了相应文献中的结果.
简介:Usingrecursivemethod,thispaperstudiesthequeuesizepropertiesatanyepochn+inGeom/G/1(E,SV)queueingmodelwithfeedbackunderLASDA(latearrivalsystemwithdelayedaccess)setup.Somenewresultsabouttherecursiveexpressionsofqueuesizedistributionatdifferentepoch(n+,n,n-)areobtained.Furthermoretheimportantrelationsbetweenstationaryqueuesizedistributionatdifferentepochsarediscovered.TheresultsaredifferentfromtherelationsgiveninM/G/1queueingsystem.Themodeldiscussedinthispapercanbewidelyappliedinmanykindsofcommunicationsandcomputernetwork.
简介:ItisknownthatthereexistsanisogenysortofChevalleygroupsG(∑,F)associatedtoanyindecomposablerootsystem∑andanyfieldF.InthispapertheauthordeterminesallnontfivialhomomorphismsfromG(∑,k)toG(∑,K)whentherootsystem∑isoftypeCnorG2,andthefieldskandKarefinitefieldsofcharacteristiep.