论连续并购与间隔并购样本的差异

在已有对并购的研究中,学者们没有细分连续并购样本和间隔并购样本。他们大多数采取两种方式:一种是把连续并购剔除在外,另一种是把连续并购和间隔并购放在一起,致使我们的并购研究无法突破。本研究选取四大类别熵,即:支持型熵、压力型熵、还原型熵、氧化型熵作为变量,利用参数和非参数检验进行样本的差异检验。最后发现:连续并购和间隔并购有实质性的区别。这给我们今后做并购研究的样本选取提供了有利的支持。     

智能变电站间隔层防误闭锁运行维护有关问题的探讨

文章通过对220 kV兴国智能变电站在间隔层防误闭锁的实践,分析了间隔层防误的原理,提出了防误闭锁规则的设计思路,总结了管理中存在的问题。     

An investigation of transformation-based prediction interval for the Weibull median life

Statistical inference based on the Weibull distribution, a distribution widely used in reliability and survival analysis, is usually difficult as it often involves numerical computation and approximation. However, this distribution can be transformed to near-normality by a simple power transformation. Based on this transformation, a prediction interval (PI) for its median can be easily constructed through an inverse transformation. The procedure for selecting the best power transformation through minimizing Kullback-Leibler information is described. The property of this transformation-based PI is investigated. Simple correction factors are also proposed. It is shown that the transformation-based PI with corrections performs well, irrespective of the sample size and parameter values. Simulation results show that the new PI generally outperforms the existing PI. Numerical examples are given for illustration.     

考虑运输时间的生产过程时间组织问题研究

在考虑运输时间的基础上,研究一批零件在工序间的移动方式,推导出含运输时间的顺序移动、平行移动和平行顺序移动方式的零件生产周期计算公式。之后,研究三种不同移动方式下,零件在各工序间的搬运次数和零件的搬运数量等问题。最后,以一个实例进行详细的分析。     

老字号品牌资产五维度探析——基于Aaker理论

作为曾经的强势品牌,老字号品牌资产流失严重,在老字号品牌资产的五个维度中:忠诚顾客偏少、趋于老化但相对牢固;品质认知度和美誉度较高;品牌联想中历史文化联想丰富而现代联想不足;知名度则限于老顾客且区域性较强,在新顾客中知名度较低;市场行为方面,市场份额低,营销能力薄弱。     

Asymptotically optimal estimation of smooth functionals for interval censoring, part 2

Estimation in the interval censoring model is considered. A class of smooth functionals is introduced, of which the mean is an example. We consider case 2, with two observation times for each unobservable event time, in the situation that the observation times cannot become arbitrarily close to each other. It is proved that the nonparametric maximum likelihood estimator of the functional asymptotically reaches the information lower bound.     

Tail index estimation based on linear combinations of intermediate order statistics

Based on linear combinations of intermediate order statistics, we introduce a new class of estimators for the exponent of a distribution function F with a regularly varying upper tail. We prove asymptotic normality and we make a comparison with existing proposals using the mean squared error as criterion.     

计算机库存控制系统的开发与应用

以库存控制论、决定支持系统理论为基础，对计算机库存控制系统的分析与设计作了深入的分析研究，提出了企业借助计算机技术实现科学控制库存的实用方法。     

Regression with errors in variables: estimators based on third order moments

In this paper consistent and, in a well–defined sense, optimal moment–estimators of the regression coefficient in a simple regression model with errors in variables are derived. The asymptotic variance and other asymptotic properties of these estimators are given. As is known for a long time, serious estimation problems exist in this model. There are two ways out of this problem: using either additional assumptions or additional information in the data. A lot of attention has been paid to the use of additional assumptions. However, quite often this leads to rather unrealistic models. In this paper we use additional information in the data. That means here that, besides first and second order moments, third order moments are formulated as functions of the model parameters. Besides theoretical derivations a small study with generated data is discussed. This study shows that for samples larger than 50 the estimates we consider behave nicely.     

基于要素构成的街道景观营建与导控

街道景观是城市意象体验的基本裁体,也是规划和建设多种要素的结构体现.通过分析城市街道景观系统的构成特点,在空间导控和营建工作两个方面提出思路策略和技术原则,探索适宜的街路界面塑造模式与特色.针对空间、要素两个方面的组成关系进行街路景观的系统解析;同时结合当前的工程实践操作,提出有效的控制与引导方法,建立街道景观建设的内部秩序.     

Measuring the readability performance (RP) of aircraft maintenance technical orders by fuzzy MCDM method and RP index

With the development of the global economy and the ease of air transportation, extra emphasis has been placed on flight safety. There are precise specifications and procedures in the operation and maintenance of aircraft. Human errors and mechanical disorders are two key factors of flight safety. The maintenance personnel need to follow an outlined procedure to avoid human errors and ensure flight safety. Readability of aircraft maintenance technical orders can affect the quality and reliability of aircraft maintenance. To ensure the editing quality of technical orders, controlling/monitoring the number of unreadable sentences is important and necessary. In this study, the number of unreadable sentences found in a technical order was used as the measure of readability performance (RP) as well as a readability performance index was provided to evaluate whether the RP of individual readability characteristics of technical orders was adequate. Different readability characteristics make different grade of RP loss. Based on fuzzy multiple criteria decision-making (Fuzzy MCDM) approaches, we investigated the expert opinions to rank and calculate the weights of all readability characteristics. At the same time, we proposed the upper limits of unreadable sentences according the weights of individual readability characteristics. In this paper, the technical orders issued by Taiwan Aerospace Industrial Development Corporation was used as an example to evaluate the readability of the technical orders and total RP losses for individual readability characteristics. Finally, an improved way of editing quality for technical orders was recommended.     

区间规划在证券投资组合问题中的运用

本文基于区间规划的方法研究了摩擦市场的投资组合选择问题。文中把风险证券的收益率、投资风险及证券的流动性用区间数来描述,并结合绝对偏差风险函数的思想建立了一种关于区间数的证券投资组合选择模型。最后利用区间数的两种序关系将所提出的模糊线性规划问题转化为普通的参数线性规划问题进而求其解。     

基于改进遗传算法的生鲜加工配送中心连续选址模型

建立了生鲜加工配送中心选址连续模型，在引入监控算子的基础上，运用改进的遗传算法对模型进行求解。该模型和改进的遗传算法可有效的解决生鲜加工配送中心的选址问题。     

The distribution of the relative arc density of a family of interval catch digraph based on uniform data

We study a family of interval catch digraph called proportional-edge proximity catch digraph (PCD) which is also a special type of intersection digraphs parameterized with an expansion and a centrality parameter. PCDs are random catch digraphs that have been developed recently and have applications in classification and spatial pattern analysis. We investigate a graph invariant of the PCDs called relative arc density. We demonstrate that relative arc density of PCDs is a U-statistic and using the central limit theory of U-statistics, we derive the (asymptotic) distribution of the relative arc density of proportional-edge PCD for uniform data in one dimension. We also determine the parameters for which the rate of convergence to asymptotic normality is fastest.     

On maximum likelihood prediction based on Type II doubly censored exponential data

In this paper, the maximum likelihood predictor (MLP) of the kth ordered observation, t _k, in a sample of size n from a two-parameter exponential distribution as well as the predictive maximum likelihood estimators (PMLE's) of the location and scale parameters, θ and β, based on the observed values t _r, …, t _s (1≤r≤s<k≤n), are obtained in closed forms, contrary to the belief they cannot be so expressed. When θ is known, however, the PMLE of β and MLP of t _k do not admit explicit expressions. It is shown here that they exist and are unique; sharp lower and upper bounds are also provided. The derived predictors and estimators are reasonable and also have good asymptotic properties. As applications, the total duration time in a life test and the failure time of a k-out-of-n system may be predicted. Finally, an illustrative example is included. Received: August 1999     

网络化生产的生产计划模型研究

本文指出了网络化生产的组织形式及网络化生产环境下生产计划的特征,着重分析了网络化生产环境下订单生产类型的决策判据问题,并在此基础上提出了网络化生产计划模型,建立了相应的线性规划算法,进一步完善网络化生产的理论体系,为网络化生产的生产管理提供支持。     

浅议武汉工程职业技术学院新区艺术楼设计思路

在武汉工程职业技术学院新校区的艺术楼的设计中,提出了中心与一体化概念,使外部秩序与内部秩序彼此尊重、相互渗透与结合,最终形成连续的空间形态,从而解决好建筑与场地的关系和创造出丰富的室内空间。     

前束一致性的控制方法分析

由于硬点坐标参数容差引起的,汽车悬架外特性参数随轮跳变化曲线的变化称为汽车悬架外特性的一致性,它是评价一种汽车产品整体质量一个重要指标。目前,还没有文献提出汽车悬架外特性一致性的具体控制方法,在汽车动力学软件中也没有汽车悬架外特性参数一致性分析的模块。所以,本文旨在利用区间数学的方法建立其一致性分析的数学模型,并用影响其一致性的硬点坐标参数容差作为区间参数,最后用区间分析方法计算其一致性结果。通过使用这种方法对双横臂独立悬架模型的前束角一致性进行分析,证明了区间分析方法计算汽车悬架外特性的一致性是可行的。     

仓储中心拣选作业研究综述

在仓储中心拣选作业中,以降低人员行走距离、提高拣选效率的研究为对象,对拣选作业中的相关研究问题和解决方案进行了讨论和综述。