一种改进的遗传算法进化有限状态机

提出了一种改进的遗传算法,针对有限状态机中输出矢量与状态转移相关的特性,将配置有限状态机的染色体分解为状态转移基因和输出矢量基因进行分阶段的进化实验。实验结果表明同传统的进化算法相比,这种分阶段进化的遗传算法降低了有限状态机进化过程中的复杂度,有效地提高了进化性能。     

参数假设检验教学中的几个问题

在概率统计教学的基础上,对参数假设检验教学中出现的学生难于理解的几个问题做了系统的总结,主要包括决策的依据,拒绝域的选择以及决策可靠性的判断,其中对做出"接受零假设"决策的可靠性给出了解释。     

Robust pairwise multiple comparisons under short-tailed symmetric distributions

In one-way ANOVA, most of the pairwise multiple comparison procedures depend on normality assumption of errors. In practice, errors have non-normal distributions so frequently. Therefore, it is very important to develop robust estimators of location and the associated variance under non-normality. In this paper, we consider the estimation of one-way ANOVA model parameters to make pairwise multiple comparisons under short-tailed symmetric (STS) distribution. The classical least squares method is neither efficient nor robust and maximum likelihood estimation technique is problematic in this situation. Modified maximum likelihood (MML) estimation technique gives the opportunity to estimate model parameters in closed forms under non-normal distributions. Hence, the use of MML estimators in the test statistic is proposed for pairwise multiple comparisons under STS distribution. The efficiency and power comparisons of the test statistic based on sample mean, trimmed mean, wave and MML estimators are given and the robustness of the test obtained using these estimators under plausible alternatives and inlier model are examined. It is demonstrated that the test statistic based on MML estimators is efficient and robust and the corresponding test is more powerful and having smallest Type I error.     

On False Discovery and Non‐discovery Proportions of the Dynamic Adaptive Procedure

This paper studies the asymptotic behaviour of the false discovery and non‐discovery proportions of the dynamic adaptive procedure under some dependence structure. A Bahadur‐type representation of the cut point in simultaneously performing a large scale of tests is presented. The asymptotic bias decompositions of the false discovery and non‐discovery proportions are given under some dependence structure. In addition to existing literatures, we find that the randomness due to the dynamic selection of the tuning parameter in estimating the true null rate serves as a source of the approximation error in the Bahadur representation and enters into the asymptotic bias term of the false discovery proportion and those of the false non‐discovery proportion. The theory explains to some extent why some seemingly attractive dynamic adaptive procedures do not outperform the competing fixed adaptive procedures substantially in some situations. Simulations justify our theory and findings.     

无机化学实验教学改革探索

分析了高校化工、生物技术、环境保护及食品工程等相关专业的专业基础课程《无机化学》实验教学改革的必要性,探索并实施了一系列有效的改革方案,取得了良好的实验教学效果.     

大学英语听力测试及应试技巧

听是四大语言技能中十分重要,但又难以掌握的一种技能。听解过程实际上是个信息加工过程,它受到诸如受试的语言知识、非语言知识及记忆力等诸方面的影响。可从听解的实质出发,分析影响听解的因素及如何采取一些有效应试技巧以求指导考生在CET4-6级中发挥最好水平。     

2000m~3二甲醚球罐的在线检测及有限元分析

首先,使用多通道声发射检测仪PAC SAMOS-48检测在用2000m3二甲醚球形储罐,判定出该设备存在表面裂纹缺陷及其所处位置。然后,采用超声波检测方法,确定了裂纹形状和大小。用Newman—Raju方法研究了表征裂纹缺陷前沿应力场以及位移场的重要参量即应力强度因子,并利用ANSYS建立简化的有限元模型,最终得到裂纹的应力云图和该裂纹前沿应力强度因子值,与工程估算方法得到的数值进行对比,结果表明有限元方法应用于压力容器缺陷的分析是适用的。     

The likelihood ratio test for homogeneity in finite mixture models

The authors study the asymptotic behaviour of the likelihood ratio statistic for testing homogeneity in the finite mixture models of a general parametric distribution family. They prove that the limiting distribution of this statistic is the squared supremum of a truncated standard Gaussian process. The autocorrelation function of the Gaussian process is explicitly presented. A re‐sampling procedure is recommended to obtain the asymptotic p‐value. Three kernel functions, normal, binomial and Poisson, are used in a simulation study which illustrates the procedure.     

Statistical analysis of a two-unit dependent repairable system

Maximum likelihood estimators are investigated a for lr-out-of 2:G repairable system when failures and repairs are statistically dependent. Under two censoring schemes Accelerated Life Testing Procedure (ALTP) is used to obtain the estimates. Information matrices are supplied and a special case when the failure and repair phenomenon are independent of each other is considered.