Mean estimate in ranked set sampling using a length-biased concomitant variable

In this paper, a ranked set sampling procedure with ranking based on a length-biased concomitant variable is proposed. The estimate for population mean based on this sample is given. It is proved that the estimate based on ranked set samples is asymptotically more efficient than the estimate based on simple random samples. Simulation studies are conducted to present the properties of the proposed estimate for finite sample size. Moreover, the consequence of ignoring length bias is also addressed by simulation studies and the real data analysis.     

General location multivariate latent variable models for mixed correlated bounded continuous,ordinal, and nominal responses with non-ignorable missing data

Using a multivariate latent variable approach, this article proposes some new general models to analyze the correlated bounded continuous and categorical (nominal or/and ordinal) responses with and without non-ignorable missing values. First, we discuss regression methods for jointly analyzing continuous, nominal, and ordinal responses that we motivated by analyzing data from studies of toxicity development. Second, using the beta and Dirichlet distributions, we extend the models so that some bounded continuous responses are replaced for continuous responses. The joint distribution of the bounded continuous, nominal and ordinal variables is decomposed into a marginal multinomial distribution for the nominal variable and a conditional multivariate joint distribution for the bounded continuous and ordinal variables given the nominal variable. We estimate the regression parameters under the new general location models using the maximum-likelihood method. Sensitivity analysis is also performed to study the influence of small perturbations of the parameters of the missing mechanisms of the model on the maximal normal curvature. The proposed models are applied to two data sets: BMI, Steatosis and Osteoporosis data and Tehran household expenditure budgets.     

中国成人外语学习中焦虑变量的分析

在中国,成人在外语学习中往往被一种焦虑状态所困扰。作为重要的情感变量之一,焦虑对外语学习的影响不容忽视。它不仅可以决定语言过滤的多少,还可以反映语言学习的进度和质量,从而最终影响语言习得的结果。造成这种焦虑的因素有主观原因和客观原因。在英语教学中,应注意从情感入手调动学生的非智力因素,实施愉快教育。     

An Examination of the Moderating Influence of Breadwinner Role Salience on the Pay Life Satisfaction Relationship

This study examined the pay life satisfactionrelationship and the moderating influence of breadwinnerrole salience among a sample of Hong Kong Chineseprofessional and managerial employees (N = 255). The results of zero-order correlational andmoderated regression analysis revealed support for thepay life satisfaction relationship. The interaction termof pay satisfaction by breadwinner role salience made a significant but rather modestcontribution to the explained variance in lifesatisfaction and this finding was not gender-specific.Results of a subgroup analysis also revealed that thepay life satisfaction relationship was significant amongthe low breadwinner role salience group but wasnonsignificant among the high breadwinner role saliencegroup. In general, the findings highlight the importance of breadwinner role salience to employees'reactions to the economic conditions of work.     

数控变量泵功率匹配节能系统的原理与实验研究

本文介绍以８０９８ 单片机控制的数控变量泵功率匹配节能系统的基本组成,工作原理及实验研究方法．     

二元判决图变量排序新方法

从遗传算法入手,利用已有的几种启发式变量排序方法的结果作为最初的染色体群体,并适当加入随机变量顺序,然后按照遗传算法的方法进行运算,经过多代循环找到近似最优解。实验结果表明,该方法比已有的启发式方法更有效,能够在全局范围内搜索最优解,对BDD的变量编序和遗传算法的运用具有参考价值。     

可变提前期的易逝品供应链协调

易逝品供应链作为供应链的一个重要分支日益受到关注,已成为现代商业活动中不可或缺的组成部分.在提前期与预测误差呈线性关系,提前期与赶工成本呈分段线性关系的前提下,建立了在分散决策、集中决策两种模式下可变提前期的易逝品供应链库存模型,设计了优化算法并通过数值分析比较了这两种模式下供应链整体及其成员收益的变化.进一步探讨了在合作的分散决策模式下,可变提前期的易逝品供应链实现渠道协调的可行性以及实现渠道协调的条件,并通过数值例子说明了模型的结论.     

“翻译”定义繁多之论析

“翻译” (本文指文学翻译 )的定义在翻译这门学科里是个看似最简单的问题 ,然而因其在国内和国外林林总总、各具特色 ,显露出复杂、深刻而又色彩斑斓的一面 ,折射出当前该学科领域热门话题———翻译理论的种种缩写。当翻译活动经历了几千年悠久的历史后 ,却仍无一条翻译定义为世人公认 ,而当今世界形形色色的翻译定义又俯拾即是 ,“这是一个颇耐玩味的事实”。在此 ,文章对这一独特的现象作了分析     

模糊评价方法在地方公用事业决策中的应用

以模糊决策模型为基础,改进了综合模糊评判方法,并采取Ａｄａｍｏ模糊数排序方法,为公用事业决策中经常遇到的清晰－模糊指标混合的选择型决策问题提供了一条解决的途径,文中还首次尝试了用模糊数构造模糊矩阵以增加决策的科学性。     

变系数齐线性方程稳定的必要条件

用等价变换和解的性质得到了变系数齐线性方程稳定的一些必要条件．