Characteristic Impedance of A GTEM Cell

保角变换－奇异积分方程法被用来求ＧＴＥＭｃｅｌ的特性阻抗，用完全椭圆积分给出了基于只有球ＴＥＭ模传播的简单而精确的特性阻抗公式。该方法使ＧＴＥＭｃｅｌ的特性阻抗的计算精确而简单。另外，采用保角变换—有限差分法求出了球ＴＥＭ模的电磁场分布和高阶模式的特性。文中的分析可用于对ＧＴＥＭｃｅｌ和宽带传线的研究。     

W波段宽带电调信号源

依据电调基频、提取谐波的构想，建立了串联型宽带变容管电调谐波振荡器的电路模型。在３ｍｍ频段上完成了电路设计，获得了１５％的相对电调带宽，带内最小功率５ｍＷ，最大功率超过１７ｍＷ；输出功率大于５ｍＷ的电调带宽达到１３ＧＨｚ。以宽带电调谐波振荡器为核心，完成了３ｍｍ电调信号源的系统设计，该信号源工作带宽１０ＧＨｚ，频率显示误差小于１００ＭＨｚ，频率稳定度（２～９）×１０－４／ｈ，可以连续波和方波两种方式工作     

一类时变调节大系统的稳定性

本文利用参数变易法来研究时变调节大系统的全局指数渐近稳定性,得到了时变调节大系统的全局指数渐近稳定性的充分条件,从而改进了文献[3]的结果。利用本文所得到的充分条件来研究文献[1～3,5]所讨论的同一例子,得到了比文献[1～3,5]更宽的指数渐近稳定性的参数区域。     

Robustness of automated data choices of smoothing parameter in image regularization

Statistical image restoration techniques are oriented mainly toward modelling the image degradation process in order to recover the original image. This usually involves formulating a criterion function that will yield some optimal estimate of the desired image. Often these techniques assume that the point spread function is known when the image is restored and indeed when we estimate the smoothing parameter. However in practice this assumption may not hold. This paper investigates empirically the effect of mis-specifying the point spread function on some data-based estimates of the regularization parameter and hence on the image reconstructions. Comparisons of image reconstruction quality are based on the mean absolute difference in pixel intensities between the true and reconstructed images.     

ASYMPTOTIC OPTIMALITY OF LIKELIHOOD RATIO TESTS FOR EXPONENTIAL DISTRIBUTIONS UNDER TYPE II CENSORING

Consider the model of k two parameter exponential populations under a type II censoring scheme. In this paper we establish optimality in the sense of Bahadur of the likelihood ratio test for an arbitrary testing problem by requiring only Condition A in Hsieh (1979). This result unifies and generalizes the results in Samanta (1986).     

旋风铣削加工外球面的研究

本文通过对旋风铣削加工球面的加工方法进行抽象,建立了数学模型,并提出了有关参数的计算公式和确定方法。     

Asymptotic distributions of functions of a sample covariance matrix under the elliptical distribution

This paper is concerned with asymptotic distributions of functions of a sample covariance matrix under the elliptical model. Simple but useful formulae for calculating asymptotic variances and covariances of the functions are derived. Also, an asymptotic expansion formula for the expectation of a function of a sample covariance matrix is derived; it is given up to the second-order term with respect to the inverse of the sample size. Two examples are given: one of calculating the asymptotic variances and covariances of the stepdown multiple correlation coefficients, and the other of obtaining the asymptotic expansion formula for the moments of sample generalized variance.     

应用正交试验法优选电火花成型加工电参数的研究

用正交试验法研究了电火花成型加工中电参数与工件加工速度、表面粗糙度和工具电极损耗比等工艺指标的关系，提出了优选的电参数方案．     

基于数据矩阵的信号频率和二维方向估计

在低信噪比和短数据环境下，基于阵列接收数据空间自协方差和互协方差矩阵分解的信号频率和二维到达方向（方位角和仰角）联合估计的性能往往较差。通过数据矩阵的奇异值分解和其Ｆｒｏｂｅｎｉｕｓ范数的低秩近似，提出了一种性能改进的新的信号频率和二维到达方向联合估计方法。计算机模拟实验证实了其有效性。     

K_3[C_r(C_2O_4)_3]·3H_2O的电子光谱的研究——10D_q、B和β参数的测定

报导了应用紫外分光光度计测定三草酸根合铬(Ⅲ)酸钾配合物的电子吸收光谱,并计算出其重要参数10D_q、B和β,所得结论与理论推出规律相吻合。