B2B电子商务模式的探讨

针对B2B模式将成为未来电子商务发展的主流,文章先从价值链角度分析了B2B电子商务模式对价值链上游的冲击,然后概括性地总结了目前主要的3种B2B电子商务模式,最后用“SWOT”战略评估方法分析了基于供应链管理的区域型B2B电子商务新模式。     

Analysis and Forecast of the State of Environmental Protection in Russia

The main purpose of the present study is to analyse the emission dynamics of atmospheric and water pollutants in Russia and cost of their removal in the 1980s and early 1990s, and to forecast them by means of a Dynamic Input–Output Model according to different scenarios of future economic development till 1998. Main results of the work are:– methodological principles have been elaborated for singling out the environmental protection sector within the national economy;– a method has been offered for including the ecological block into a Dynamic Input–Output Model of the Russian economy;– a method of data preparation has been elaborated for the ecological block of the above-named model, the data base which characterizes the ecological situation in Russia has been formed and analysed;– calculations for 1994–1998 have been executed for forecasting the economic and ecological development of Russia using the above-mentioned model and the results obtained have been analysed. The results showed that if the existing tendencies towards low environmental protection capital costs remain the same, then the negative environmental impact will increase. In order to implement ecological programs and international agreements, to increase the proportion of removed pollutants, it is necessary to increase substantially expenditures on purifying water and air resources. The proportion of environmental protection investments in the total amount of the national economy capital costs should increase by up to 12–40% according to different scenarios of the economic development and different purposes of the environmental protection policy.     

基于BP神经网络的我国M2/GDP预测与对策

本文计算了1993年至2005年我国M2/GDP,发现该数据总体呈上升趋势,这一定程度上反映了我国体制上的深层次问题。另外,本文运用带有动量项和自适应学习率的BP神经网络方法预测出我国2006年的M2/GDP是1.6386左右,并提出了一些相应的政策建议。     

一种灵活的ADO方式的SQL Server数据连接方法

在基于SQLServer数据系统的C/S开发中,大多数的开发平台与数据库的连接在应用中使用的是固定参数的连接模式,灵活性很差,对于服务器端的可维护性(如服务器更名,IP地址的改变,多数据库系统混合应用等)变得越来越弱,同时维护成本也随之提升,有的甚至服务器系统安装完毕后除了数据备份之外便一直不作任何变动,在安全性和数据库系统混合运用上形成很多不兼容的问题。本文提供了一种基于TCP/IP的客户机与SQLServer连接方法(使用VB开发环境描述),使得无论服务端还是客户端的维护和应用具备高度灵活性也便于安全性维护,同时这种方法也适应于广域网环境的应用。     

基于UML及B/S架构网上选课系统的设计与实现

利用系统用例图、类图及对象顺序图的实例介绍了UML建模技术,并运用B/S架构及ASP技术讨论了网上选课系统的实现。     

中国股市市盈率分布特征及国际比较研究

本文对市盈率的内涵、计算方法、区间确定等理论问题进行了剖解 ,针对中国股市流通股、非流通股并存等特征 ,对市盈率在中国股市的计算方法进行了分析 ;在此基础上对中国股市市盈率分布特征进行实证分析和国际比较研究 ,认为目前沪深股市泡沫成份已较少 ,市盈率在合理区间之内 ,中国股市具有投资价值     

TCP/IP拥塞控制研究

综述了Internet上TCP/IP拥塞控制研究方面一些最新的工作,分析了拥塞控制的原理、TCP/IP拥塞控制所使用的典型技术,并着重论述了TCP/IP拥塞控制所面临的问题,包括自相似性问题、效率问题、区分服务等问题,并提出进一步研究的方向。     

Expected utility theory and the experiments

The experimental evidence against expected utility theo or unconvincing. When one modifies the experiments to mi tends to support traditional theory.Dewey H. Johnson Professor of Economics, Department of Economics, College of Business Administration, University of South Carolina. I am grateful for comments from seminar participants at the University of Melbourne, University of South Carolina, University of Stockholm, and the University of Western Ontario. John Hey provided a firm, but sympathetic, editorial hand.     

Managerial judgment and forecast combination: An experimental study

This paper examines the role of managerial judgment in forming a final forecast, or judging the achievability of a critical level of sales, when multiple forecasts or opinions are available to the decision maker. Several factors that can help improve the quality of human intervention are identified and incorporated in a decision aid. Experimental results show that aided combination can help the decision maker exploit her relevant private information and mitigate the generally observed negative effects of human intervention. Further, the results suggest that emphasizing expected sales, even when the organization is primarily interested in go/no-go decisions, helps improve performance. Several suggestions for future research are presented.

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Problem-solving in teaching/learning packages for Technology

In the project Technology in Secondary Education: Problem-solving in Teaching/learning Packages, two experiments regarding a construction problem and an explanation problem were conducted, in which two variants of a teching/learning package (strongly structuredvs. weakly structured) were compared. Only with the strongly structured instructional variant of the package for the explanation problem did the pupils come to a quick solution of the problem. In both experiments, the factors that influenced the problem-solving processes of the pupils were investigated. The results are of importance for curriculum developers and the authors of teaching/learning packages for Technology but further research into the factors influencing the problem solving process of pupils is necessary.