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91.
A method of estimating initial conditions of coupled maplattices based on time-varying symbolic dynamics 下载免费PDF全文
A novel computationally efficient algorithm in terms of the time-varying
symbolic dynamic method is proposed to estimate the unknown initial
conditions of coupled map lattices (CMLs). The presented method
combines symbolic dynamics with time-varying control parameters to
develop a time-varying scheme for estimating the initial condition
of multi-dimensional spatiotemporal chaotic signals. The
performances of the presented time-varying estimator in both
noiseless and noisy environments are analysed and compared with the
common time-invariant estimator. Simulations are carried out and the
obtained results show that the proposed method provides an efficient
estimation of the initial condition of each lattice in the coupled
system. The algorithm cannot yield an asymptotically unbiased
estimation due to the effect of the coupling term, but the estimation
with the time-varying algorithm is closer to the Cramer--Rao lower bound
(CRLB) than that with the time-invariant estimation method,
especially at high signal-to-noise ratios (SNRs). 相似文献
92.
采用阳极修饰法构建了基于酞菁铜(CuPc)和碳60(C60)的有机小分子太阳电池,分别研究了酞菁锌(ZnPc)、聚苯乙烯磺酸(PEDOT:PSS)和PEDOT:PSS/ZnPc作为阳极修饰层对该有机太阳电池输出性能的影响,并对三种修饰层的相关机理进行了探讨.结果表明:加入ZnPc修饰层的电池开路电压(Voc)增大,从0.372提高到0.479 V.旋涂PEDOT:PSS的电池短路电流(Jsc)提高,由1.943 mA/cm2提高到3.752 mA/cm2.而以PEDOT:PSS/ZnPc作为阳极修饰的电池Voc和Jsc均有较大的提高,Voc从 0.372 V提高到0.482 V,Jsc从1.943 mA/cm2提高到3.810 mA/ cm2,其转换效率可提高两倍以上.分析认为,ZnPc更有利于阳极空穴的输出,PEDOT:PSS能有效改善ITO表面的平整度的性质是提高太阳电池性能的主要原因. 相似文献
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95.
Ultra-low temperature radio-frequency performance of partially depleted silicon-on-insulator n-type metal-oxide-semiconductor field-effect transistors with tunnel diode body contact structures 下载免费PDF全文
Radio-frequency(RF) characteristics under ultra-low temperature of multi-finger partially depleted silicon-oninsulator(PD SOI) n-type metal-oxide-semiconductor field-effect transistors(nMOSFETs) with tunnel diode body-contact(TDBC) structure and T-gate body-contact(TB) structure are investigated in this paper.When operating at 77 K,TDBC device suppresses floating-body effect(FBE) as well as the TB device.For TB device and TDBC device,cut-off frequency(f_T) improves as the temperature decreases to liquid-helium temperature(77 K) while that of the maximum oscillation frequency(/max) is opposite due to the decrease of the unilateral power gain.While operating under 77 K,f_T and f_(max) of TDBC device reach to 125 GHz and 77 GHz,representing 8%and 15% improvements compared with those of TB device,respectively,which is mainly due to the lower parasitic resistances and capacitances.The results indicate that TDBC SOI MOSFETs could be considered as promising candidates for analog and RF applications over a wide range of temperatures and there is immense potential for the development of RF CMOS integrated circuits for cryogenic applications. 相似文献
96.
以2012年2月下旬至3月上旬浙江省的一次长连阴雨过程为研究对象,利用客观资料对连阴雨形成的环流特征、水汽条件和动力条件进行了研究分析,得到:(1)2012年连阴雨期间乌拉尔山地区的阻高明显偏强,冷空气、南支槽与副高的稳定维持且20 d基本没变,为浙江省形成连阴雨天气提供了必要的环流背景;(2)从孟加拉湾和南海吹来的偏南风为连阴雨的形成提供了充足的水汽条件;(3)动力结构呈低层辐合、高层辐散配置,气流的上升运动和涡度式抽吸作用的强弱在雨势变化中起主导作用,低层辐合区和高空辐散区的强度变化与雨势变化相一致. 相似文献
97.
某些导电高分子的波谱性能 总被引:3,自引:0,他引:3
本文以聚吡咯和聚噻吩为例,对导电高分子的紫外-可见光谱、红外光谱、远红外及微波区的波谱性能进行了综述,并分析了波谱性能与结构的关系。对导电高分子波谱性能的实际应用前景也进行了论述。 相似文献
98.
Let{V,,jeZ}beamu1tiresolution,withV;gV,+,.Inpractice,weoftenneedtoconsidertheequi-appr0ximati0nofamultiresolution(seeLl'2'3J)toafunctionspaceVorafunctionsetF.ThiscanbewrittenaswhereVGL'(R"),F=L'(R"),VI=L'(R')(IeZ),andPv,isaprojectionoperatorofLz(R")-Vz.ThuswecanusePv,finsteadoff,approximately.Investigati0nofthisproblemhasveryimportantpraticalvalueandthe0reticalsignificance.Considerations0fthisquestionalsoleadtobetterunderstandingformultiresolution.FromTheorem2weknowthatforalljeZ,V… 相似文献
99.
Two Superconducting Phases and Their Characteristics in Layered BaTi2(Sb1-xBix)2O with x=0.16 下载免费PDF全文
Two correlated superconducting phases are identified in the layered superconductor BaTh (Sb1-xBix)2O (x = 0.16), with the superconducting transition temperatures of Tc = 6K (the high Tc phase) and 3.4K (the low Tc Phase), respectively. The 6K superconducting phase appears first in the as-prepared sample and can decay into the low TC phase by exposure to an ambient atmosphere for a certain duration. Specially, the high Tc phase can reappear from the decayed sample with the low Tc phase by vacuum annealing. It is also found that the CDW /SDW order occurs only with the 6 K superconducting phase. These notable features and alteration of the superconductivity due to the post-processing and external pressure can be explained by the scenario of electronic phase separation. 相似文献
100.
提供了关于元电荷测试、有关密立根油滴实验以及其中数据处理的争议点的历史研究若干线索.简要介绍了一些相关文献,希有助于初涉这段历史的读者迅速接触核心.对可能长期存在的偏倚期盼现象作了较多摘引以期引起关注. 相似文献