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81.
测量以GaAs为衬底的Zn1-xCdxSe/ZnSe应变层多量子阱在不同温度下(18~300K)的光伏谱,研究Zn1-xCdxSe/ZnSe多量子阱的光伏效应和带间激子跃迁,实验结果表明,Zn1-xCdxSe/ZnSe量子阱具有显著的量子限制效应,从18K直至室温,都能观测到清晰的激子跃迁峰,说明Zn1-xCdxSe/ZnSe是制作室温下工作的蓝绿激光器等发光器件的合适材料。 相似文献
82.
陈艳晶 《济南大学学报(社会科学版)》1995,(2)
本文用原子吸收分光光度法测试人发中微量元素铬的含量,用1:1的硝酸,在高压消化罐中消化处理发样,测试结果,比之用其他化学方法消化发样,测试精度高,回收率好,一般在96%~107%.且节省试剂,操作简单,是目前较理想的样品消化方法. 相似文献
83.
Meng-Ning Lyu Qing-Shan Yang Na Yang Siu-Seong Law 《Journal of applied statistics》2016,43(5):827-846
A wooden historic building located in Tibet, China, experienced structural damage when subjected to tourists visit. This kind of ancient building attends to too many visitors every day because heritage sites never fail to attract tourists. There should be a balance between accepting the visitors and the protection of historic buildings considering the importance of the cultural relics. In this paper, the singular spectrum analysis (SSA) is used for forecasting the number of tourist for the building management to exercise maintenance measures to the structure. The analyzed results can be used to control the tourist flow to avoid excessive pedestrian loading on the structure. The relationship between the measured acceleration from the structure and the tourist number is firstly studied. The root-mean-square (RMS) value of the measured acceleration in the passage route of the tourist is selected for forecasting future tourist number. The forecasting results from different methods are compared. The SSA is found slightly outperforms the autoregressive integrated moving average model (ARIMA), the X-11-ARIMA model and the cubic spline extrapolation in terms of the RMS error, mean absolute error and mean absolute percentage error for long-term prediction, whereas the opposite is observed for short-term forecasting. 相似文献
84.
研究了一类两个并联部件的可修系统的动力算子,应用泛函分析方法和C0半群理论,获得了系统算子的较细致的谱分布的结果.据此结果获得了系统解的有限表示和某些可靠性指标. 相似文献
85.
Peyton Cook 《统计学通讯:理论与方法》2013,42(9):2697-2715
This article describes a Bayesian small sample approach to making inferences for the operator (or filter) and squared gain of a p — th order Gaussian univariate autoregressive process. Simultaneous pos¬terior probability bands are developed for the real and the imaginary parts of the frequency-response function of an autoregressive operator as well as for the squared gain of an autoregressive process. 相似文献
86.
本文研究了一项2n阶复系数J-对称微分算式生成的J-自伴微分算子谱的离散性,得到了一项2n阶J-自伴微分算子的谱是离散的充分条件. 相似文献
87.
In the present study we examined the effects of token reinforcement on the convergent control of immediate and temporally removed verbal stimuli over the verbal behavior of three school-age children with autism who showed specific deficits in intraverbal responding. Throughout the study, participants were systematically introduced to a series of visitors to a university-based autism center, and subsequently probed for information about the visitor they had most recently met. Results show that contingent token reinforcement was effective at establishing control by temporally removed verbal stimuli. 相似文献
88.
在J-对称算子扩张基本理论的基础上,运用Naimark谱核的方法,得到J-对称算子扩张为J-自伴算子后其谱的变化情况. 相似文献
89.
借助Naimark关于2n阶对称微分算式所生成最小算子L0之任何自伴扩张Lu的谱是离散的充分条件定理,利用Lidskii方法,得到了2n阶J-自伴微分算子的谱是离散的另一个充分条件. 相似文献
90.
A method is proposed for both estimating and correcting a translational mis-alignment between digital images, taking account of aliasing of high-frequency information. A parametric model is proposed for the power- and cross-spectra of the multivariate stochastic process that is assumed to have generated a continuous-space version of the images. Parameters, including those that specify misalignment, are estimated by numerical maximum likelihood. The effectiveness of the interpolant is confirmed by simulation and illustrated using multi-band Landsat images. 相似文献