An analysis of the process generating de facto standards in the PC spreadsheet software market

This paper develops a model to analyze the emergence of de facto or market defined compatibility standards in the market for PC spreadsheet software over the period 1982–1988. The model is capable of integrating diverse fragments of empirical evidence and a number of important theoretical building blocks, in particular the analysis of gateways between different versions of the same package, product preannouncements, and diverse consumer tastes towards intrinsic quality and network externalities. The model also explores the implications of different functional forms for the relationship between installed base and the value of network externalities. The paper finds that at least some enhancements to the basic model of standards have to be incorporated to offer a reasonable approximation to developments in the PC spreadsheet software market. The simplest model of de facto standards is not able to describe developments in this market.     

循环经济视角下水泥工业和垃圾处理产业的“双赢”选择——利用新型干法窑处理城市生活垃圾

本文以现代新型干法水泥生产技术为基础,在描述城市生活垃圾的危害和处理现状之后,以循环经济三原则为切入点,结合中材国际南京水泥工业设计研究院承担的具体研发项目——铜陵市“利用水泥工业新型干法窑处置生活垃圾工程”,说明利用新型干法窑处理生活垃圾,不仅能实现能源、资源消耗的减量化,还可以使生活垃圾减容化、资源化,提升环境污染控制的容量,避免环境污染,是水泥工业扩大废物利用范围、发展循环经济、创建垃圾处理产业的有效途径,实现了水泥工业和垃圾处理产业的“双赢”。     

Searching for empirical linkages between demographic structure and economic growth

Demographic structure could affect economic growth through many channels. However, little is known about how demographic structure affects economic growth since no study has examined an extensive collection of channels through which demographic structure could affect economic growth in a single context. This paper overcomes this limitation by examining 45 potential mediating variables between demographic structure and economic growth. A causal search algorithm is used to identify channels through which demographic structure affects economic growth. Our results suggest that demographic structure affects economic growth differently between developed and developing countries. For developed countries, we find that an increase in the share of middle-aged workers has a positive effect on economic growth through institutions, investment and education channels. On the other hand, an increase in the share of the senior population has a negative effect on economic growth through institutions and investment channels. For developing countries, we find (but with weak evidence) that an increase in the share of young workers has a negative effect on economic growth through investment, financial market development and trade channels.     

PC小箱梁开裂机理有限元仿真分析

以福建省某30米跨径预制小箱梁桥为依托实例,利用Midas Fea土木专用非线性软件对PC小箱梁在施工期间预应力的偏位及预应力偏位与超张拉综合作用是否会导致箱梁底板产生纵向裂缝进行了仿真分析计算,通过对不同预应力偏位程度及超张拉多种分析工况的计算结果分析比较,研究PC小箱梁开裂原因,为PC小箱梁混凝土防裂提供理论依据。     

基于触摸式一体机的仪表综合试验台设计

文章从硬件设计和软件开发两方面描述了触摸式一体机仪表综合试验台的研发。通过基于Windows CE操作系统下的控制平台,实现了仪器仪表测量数据的自动保存及打印功能。     

河北省占领网上马克思主义阵地的调查与研究

占领网上马克思主义阵地已成为新时代的新课题,从网络发展、红色网站建设、党员上网学习状况等各个方面来看,马克思主义网上阵地还需要高度重视并进行认真建设。     

顾客重购意愿的品牌资产维度研究——以笔记本电脑行业为例

从影响顾客重复购买意愿的众多因素中探索其与品牌资产维度的联系，寻求不同品牌资产维度影响顾客重购意愿的方式与路径。作者基于笔记本电脑行业的调查研究，发现品牌认知、感知价值是直接影响顾客重购意愿的品牌资产关键维度，而品牌形象、感知质量和品牌独特性则通过品牌认知、感知价值间接影响顾客重购意愿。其中品牌形象对于品牌认知具有主导作用，感知价值的主要来源为品牌的独特性。     

基于WEB Services技术在物流上的应用

物流软件经常需要从服务器上的程序中获取数据或者把客户端的数据发送到应用程序中去。即使在同一个平台上．不同软件厂商生产的各种软件也常常需要集成起来。由于物流软件与企业ERP软件问平台、语言等差异．影响了信息资源的有效融合,用Web Service集成应用程序,可有效解决此问题。通过在Pocket PC（客户端）上远程调用Web Services发布的接口函数,实现与服务器端信息交互的例子．阐述了Web Services技术在物流上的应用过程。     

监控系统在粮食储备库中的优化设计

以粮食储备库的控制系统项目为背景,重点阐述西门子WINCC7.0在粮食储备库的优化设计。本文介绍系统硬件的组成,PLC与上位机的通讯,使用WINCC组态软件开发上位机的HMI界面,通过实施获得了较好的控制效果。WINCC监控系统的优化设计,提高了系统的易用性,减少了设备停机时间,避免了操作员的误操作等。     

五味子发芽抑制物质的生物鉴定初报

阐述了五味子发芽抑制物质的提取，用层析法测得了种皮、果肉及种仁中抑制物质在层析上Ｒｆ值不同，并通过五味子果实各部位提取液层析，对莴苣种子的发芽影响做生物鉴定。