论北宋词的女性化特征演进史

本文在阐释了词的女性化特征的前提下,主要描述了北宋词的女性化特征演进历程。笔者先对北宋词史链条上的每一个词人的风格进行个案梳理,然后用史学模式和史学思维重新构建北宋词女性化特征发展流变的整体框架。柳永、东坡、美成等的个案研究意在梳理出词人之间在词风上互相传承的关系,以此归结出词的本质属性--女性化特征的演进过程。     

Analysis of the performance of test statistics for detection of outliers (additive,innovative, transient,and level shift) in AR (1) processes

Outlier detection has always been of interest for researchers and data miners. It has been well researched in different knowledge and application domains. This study aims at exploring the correctly identifying outliers using most commonly applied statistics. We evaluate the performance of AO, IO, LS, and TC as vulnerability to spurious outliers by means of empirical level of significance (ELS), power of the test indicating the sensitivity of the statistical tests in detecting changes and the vulnerability to masking of outliers in terms of misspecification frequencies are determined. We have observed that the sampling distribution of test statistic η_tp; tp = AO,?IO,?LS,?TC in case of AR(1) model is connected with the values of n and φ. The sampling distribution of η_TC is less concentrated than the sampling distribution of η_AO, η_IO, and η_LS. In AR(1) process, empirical critical values for 1%, 5%, and 10% upper percentiles are found to be higher than those generally used. We have also found the evidence that the test statistics for transient change (TC) needs to be revisited as the test statistics η_TC is found to be eclipsed by η_AO,?η_LS and η_IO at different δ values. TC keeps on confusing with IO and AO, and at extreme δ values it just gets equal to AO and LS.     

MIMO通信系统的信道估计及其FPGA实现

本文提出在4发多收天线配制的MIMO系统中基于训练序列的信道估计算法,详细研究了该算法的FPGA实现。采用我们提出的FPGA实现方法可以大大减少信道估计中矩阵乘法操作。实测结果表明实现方案很好的吻合了理论值。     

异步CDMA系统中的盲多用户检测算法

针对实际应用中的DS/CDMA系统多为多径衰落信道下的异步DS/CDMA系统情况,通过对用于AWGN信道下的同步DS/CDMA系统中的常规盲多用户检测算法的改进,使这类算法在多径衰落信道下的异步DS/CDMA系统中仍具有很好的性能。理论分析和计算机仿真结果证实了改进方法的可行性。     

磁致伸缩作动器连续模型辨识

提出了一种采样数据中存在高频有色噪声的连续模型辨识方法,并将其应用到磁致伸缩作动器的连续模型辨识中。该方法通过引入积分运算,将连续时间系统的微分方程转换为积分方程,从而使噪声的影响可以忽略,直接利用传统的最小二乘法估计出连续时间模型。仿真实例验证了该方法的有效性和可行性,辨识的磁致伸缩作动器具有较高的可信度。     

Some Limit Behaviors for Linear EV Model with Replicate Observations

In this article, we establish the asymptotic normality for the LS estimators of the unknown parameters in the linear errors-in-variables (EV) model with replicate observations, which weaken the moment conditions of Zhang and Chen (2002 Zhang, S.G., Chen, X.R. (2002). On asymptotic normality of parameters in linear EV model. Chin. Ann. Math. Ser. B 23(4):495506.[Crossref], [Web of Science ®] , [Google Scholar]). Furthermore, the moderate and large deviations principles for the LS estimators are obtained also.     

A combinatorial estimation approach for storage reliability with initial failures based on periodic testing data

Storage reliability that measures the ability of products in a dormant state to keep their required functions is studied in this paper. Unlike the operational reliability, storage reliability for certain types of products may not be always 100% at the beginning of storage since there are existing possible initial failures that are normally neglected in the models of storage reliability. In this paper, a new combinatorial approach, the nonparametric measure for the estimates of the number of failed products and the current reliability at each testing time in storage, and the parametric measure for the estimates of the initial reliability and the failure rate based on the exponential reliability function, is proposed for estimating and predicting the storage reliability with possible initial failures. The proposed method has taken into consideration that the initial failure and the reliability testing data, before and during the storage process, are available for providing more accurate estimates of both initial failure probability and the probability of storage failures. When storage reliability prediction that is the main concern in this field should be made, the nonparametric estimates of failure numbers can be used into the parametric models for the failure process in storage. In the case of exponential models, the assessment and prediction method for storage reliability is provided in this paper. Finally, numerical examples are given to illustrate the method. Furthermore, a detailed comparison between the proposed method and the traditional method, for examining the rationality of assessment and prediction on the storage reliability, is presented. The results should be useful for planning a storage environment, decision-making concerning the maximum length of storage, and identifying the production quality.     

A comparison of LS/ML and GMM estimation in a simple AR(1) model

This paper compares least squares (LS)/maximum likelihood (ML) and generalised method of moments (GMM) estimation in a simple. Gaussian autoregressive of order one (AR(1)) model. First, we show that the usual LS/ML estimator is a corner solution to a general minimisation problem that involves two moment conditions, while the new GMM we devise is not. Secondly, we examine asymptotic and finite sample properties of the new GMM estimator in comparison to the usual LS/ML estimator in a simple AR(1) model. For both stable and unstable (unit root) specifications, we show asymptotic equivalence of the distributions of the two estimators. However, in finite samples, the new GMM estimator performs better.