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151.
Daniel W. Kee Susan Nakayama Siaw Linda Carter 《Contemporary educational psychology》1985,10(3):268-274
An experiment was conducted to evaluate constructive memory in fourth-grade low-SES black and middle-SES white children. The children were read nine short passages; each passage was composed of two premise statements and a filler sentence. The children were tested by a recognition procedure. Thirty-six test sentences were presented randomly. Four sentences were associated with each passage (true premise, false premise, true inference, and false inference). Subjects were asked to make yes/no recognition decisions based on whether the test sentence was identical to a sentence presented at study. Middle-SES white children made few errors, except to true inference test sentences. This pattern of performance is consistent with the constructive view of memory. Low-SES black children also had a high error rate to true inference items. However, this outcome may not reflect constructive memory because they also had a high error rate to some of the other types of test sentences. 相似文献
152.
程希骏 《上海海事大学学报》1990,(4)
本文着重介绍了年现金流量的随机性和连续性,并叙述了连续分布现金流的经济指标的概率分析。整个分析是按独立和相关两种情况进行的。 相似文献
153.
辽太祖东征渤海后,从现实出发将精通汉唐文化,拥有文治武功的皇太子耶律倍改封人皇王,建立东丹国,因宜为势治理渤海的同时,以期消除大举南下辟地的分歧,实现思想统一,最终酬其中国之志。这种变化同时也取决于耶律倍的个人素质。 相似文献
154.
The Common Core State Standards and Response to Intervention are significant contemporary educational initiatives that have emerged largely in isolation from one another. We argue that an integration of these initiatives is beneficial. We trace the independent development of these two initiatives and offer suggestions for how they might fruitfully transact, fully supporting vulnerable readers in their efforts to master sophisticated standards. Results from a school implementing these initiatives as an integrated whole are discussed. 相似文献
155.
John C. Wagaman 《Teaching Statistics》2017,39(2):52-56
This article describes four semesters of introductory statistics courses that incorporate service learning and gardening into the curriculum with applications of the binomial distribution, least squares regression and hypothesis testing. The activities span multiple semesters and are iterative in nature. 相似文献
156.
157.
分析了基于二阶统计的CSPRIT算法在空间相关高斯噪声环境中存在的问题,提出将四阶累积量与CSPRIT算法相结合,处理一维二元相移键控信号(BPSK)和多元幅移键控信号(MASK),实现信号到达角(DOA)的估计和波束形成器的构造。与基于二阶统计的CSPRIT算法相比,基于四阶累积量的改进算法能够有效抑制空间相关的高斯噪声,提高信号估计精度。计算机仿真验证了该算法的有效性。 相似文献
158.
A new delayed state-variable model for networked control systems is presented, upon which a linear quadratic regulator (LQR) is designed. A method of delays-estimation online is also given. A fuzzy logic with LQR controller is addressed for the difficulty on implementation of LQR in networked control systems (NCSs) with time-variant delays. Simulation results prove that the novel controller can make the system stable and robustly preserve the performance in terms of time-variant delays. 相似文献
159.
提出了用改进式电流传送器实现二阶电流模式状态变量滤波器新电路,并由此得到了高通、带通、低通滤波特性。计算机仿真结果表明理论分析是正确的,所提电路具有灵敏度甚低的特点。 相似文献
160.
Ayd?n K?z?lkaya 《Journal of The Franklin Institute》2005,342(1):39-67
In this paper, the problem of estimating the parameters of a two-dimensional autoregressive moving-average (2-D ARMA) model driven by an unobservable input noise is addressed. In order to solve this problem, the relation between the parameters of a 2-D ARMA model and their 2-D equivalent autoregressive (EAR) model parameters is investigated. Based on this relation, a new algorithm is proposed for determining the 2-D ARMA model parameters from the coefficients of the 2-D EAR model. This algorithm is a three-step approach. In the first step, the parameters of the 2-D EAR model that is approximately equivalent to the 2-D ARMA model are estimated by applying 2-D modified Yule-Walker (MYW) equation to the process under consideration. Then, the moving-average parameters of the 2-D ARMA model are obtained solving the linear equation set constituted by using the EAR coefficients acquired in the first step. Finally, the autoregressive parameters of the 2-D ARMA model are found by exploiting the values obtained in first and second steps. The performance of the proposed algorithm is compared with other 2-D ARMA parameter and spectral estimation algorithms available in the technical literature by means of three different criteria. As a result of this comparison, it is shown that the parameters and the corresponding power spectrums estimated by using the proposed algorithm are converged to the original parameters and the original power spectrums, respectively. 相似文献