正交实验设计方法在B to B电子商务体系质量改进中的应用

电子商务在全球快速地发展，中国企业面临着由B to C方式向B to B方式的转变，本文采用正交实验设计的方法来解决已建成电子商务体系的质量，以满足新的需求。     

A note on the existence of unique equivalent martingale measures in a Markovian setting

Simple sufficient conditions for the existence of a unique equivalent martingale measure are provided. Furthermore, these conditions give us a handle on situations where an equivalent martingale measure cannot exist. The existence of a unique equivalent martingale measure is of relevance to problems in mathematical finance. Two examples of models for which the question of existence was unresolved are studied. By means of our results existence of a unique equivalent measure up to an explosion time is proved.     

DS-optimal designs in one way ANOVA

Characterization and construction of optimal designs using the familiar optimality criteria, for example A-, D- and E-optimality are well studied in the literature. However the study of the Distance Optimality (DS-) criterion introduced by Sinha (1970) has very recently drawn attention of researchers. In the present article, we consider the singularly estimable full rank problem of estimating the full set of elementary treatment contrasts using the DS optimality criterion in the set up of a one way ANOVA model. Using a limit argument it turns out that a CRD in which difference between any two allocation numbers is at the most unity is uniquely DS-optimal. Acknowledgement. We are thankful to Prof. B. K. Sinha for suggesting the problem to us and many helpful discussions with him. We are also thankful to the referees for drawing our attention to the reference of Bischoff (1995) and many helpful comments.     

The European high-speed train network: Predicted effects on accessibility patterns

The principal aim of this paper is to evaluate the impact of the future European high-speed train network on accessibility, by reducing time distance between places and modifying their relative location. We compare the current situation with that foreseen for the year 2010, according to the Outline Plan of the European High-Speed Train Network, in order to analyse which areas will most benefit from construction and improvement of the infrastructure. It is hypothesized that the high-speed train will certainly bring the peripheral regions closer to the central ones, but will also increase imbalances between the main cities and their hinterlands. A weighted average distance indicator is applied for this purpose. This measure identifies the spatial distribution of accessibility in the area of study, emphasizing the infrastructure effects, and locates accessibility changes at the European level. A Geographic Information System (GIS) has been used to carry out this study.     

科技英语中数量增减的译法

本文系统地归纳了在科技文献中常见的涉及到倍数增减的结构及其表达方式     

工程项目计划管理系统设计与实现

本文通过研究分析工程项目管理的具体运行过程,采用结构化分析方法对工程项目组织机构、业务活动进行了详细的系统分析,建立了工程项目计划管理系统基本数据库,具体实现了工程项目计划管理系统的各功能模块,提出运用计算机辅助决策技术开发工程项目计划管理系统的必要性和可行性.     

基于制约理论的成本管理模式研究

环境的变化要求相应的成本管理模式发生变革。本文首先分析了环境变化对企业成本管理的影响,之后对作业成本法的管理思想的前提假设进行分析,指出它对于现代企业成本管理的局限性及其产生这些局限性的主要原因。最后,在分析制约理论核心原理的基础上,提出了一种基于制约理论的成本管理模式,试图为研究适应现代企业的成本管理模式提供新的思路。     

国有企业“债转股”政策:功能缺陷与制度依赖——项基于国有企业“债转股”政策跟踪调查的研究

伴随着我国经济体制改革向纵深发展,国有企业负债比率过高的问题更加突出显示出来。为了解决这个问题,我国实施了“债转股”政策。本文讨论四个命题:(1)国有企业是负债比率过高还是收益率过低;(2)“债转股”政策究竟是使国有企业“财务解困”还是“体制解困”;(3)“债转股”政策究竟是转移金融风险还是化解金融风险;(4)资产管理公司为国有企业和国有商业银行解困,将来谁为资产管理公司解困。本文认为“债转股”政策设计存在功能缺陷与制度依赖。国有企业“债转股”政策的成功依赖于国有企业(商业银行)现代企业制度的建立与完善。     

Robustness issues in multilevel regression analysis

A multilevel problem concerns a population with a hierarchical structure. A sample from such a population can be described as a multistage sample. First, a sample of higher level units is drawn (e.g. schools or organizations), and next a sample of the sub‐units from the available units (e.g. pupils in schools or employees in organizations). In such samples, the individual observations are in general not completely independent. Multilevel analysis software accounts for this dependence and in recent years these programs have been widely accepted. Two problems that occur in the practice of multilevel modeling will be discussed. The first problem is the choice of the sample sizes at the different levels. What are sufficient sample sizes for accurate estimation? The second problem is the normality assumption of the level‐2 error distribution. When one wants to conduct tests of significance, the errors need to be normally distributed. What happens when this is not the case? In this paper, simulation studies are used to answer both questions. With respect to the first question, the results show that a small sample size at level two (meaning a sample of 50 or less) leads to biased estimates of the second‐level standard errors. The answer to the second question is that only the standard errors for the random effects at the second level are highly inaccurate if the distributional assumptions concerning the level‐2 errors are not fulfilled. Robust standard errors turn out to be more reliable than the asymptotic standard errors based on maximum likelihood.