Is Private R & D Spending Sensitive to Its Price? Empirical Evidence on Panel Data for Italy

In this paper empirical evidence is presented on theelasticity of private R & D spending on its price. Acensored panel-data regression model with random effectsis applied to a balanced panel of 726 Italian firms overthe 1992–1997 period. Implied estimates point out thatItalian firms' response to policy measures (including taxcredits), aimed at reducing the user cost of R & D capital,is likely to be substantial (1.50–1.77). Furthermore, wealso find that the elasticity of R & D spending is higherin recession (2.01) than in expansion (0.87).     

Simulation driven inferences for multiply imputed longitudinal datasets*

In this article, we demonstrate by simulations that rich imputation models for incomplete longitudinal datasets produce more calibrated estimates in terms of reduced bias and higher coverage rates without duly deflating the efficiency. We argue that the use of supplementary variables that are thought to be potential causes or correlates of missingness or outcomes in the imputation process may lead to better inferential results in comparison to simpler imputation models. The liberal use of these variables is recommended as opposed to the conservative strategy.     

面向电子商务的现代物流管理信息系统的开发

结合现代物流技术发展趋势，分析探讨了面向电子商务的现代物流管理信息系统的开发技术路线，关键技术内容，功能体系结构设计及分层逻辑模型设计。     

基于高频数据的深圳基金市场日内周期性研究

本文利用深市基金指数高频数据,采用Anderson和Bollerslev(1997)提出的弹性傅立叶回归(FlexibleFourierFormregression,即FFF回归)方法首次对深市基金市场进行了日内周期性的研究。通过对高频收益的定性分析,发现基金市场具有同股票市场相似的周期性,并对这一周期性进行了初步的理论解释。通过FFF方法,将该周期因子进行滤波处理以后,基金指数高频绝对收益不再具有明显周期性。FFF回归能较好地确定日内周期因子。     

市场化与经济增长:一个短期的因果关系检验

利用我国1999-2002年省际区域的面板数据,运用面板数据Granger因果关系检验技术,对我国市场化水平与经济增长的关联度进行了实证分析.得出市场化是经济增长的Granger原因,但是经济增长不是市场化的Granger原因的结论.     

Knowledge integration via the fusion of the data models used in automotive production systems

ABSTRACT

In this paper a novel information model that can be used in Manufacturing Execution Systems is presented. The model is based on the fusion of ISA95, AML and OPC UA. ISA95 is used to define, unify and describe the details of a product and production technology. It also enables communication with ERP systems. The AML standard allows information about the production facilities to be presented. The OPC UA address space represents different parts of an information model while the OPC communication protocol enables it to be linked to actual production systems. The proposed concept is illustrated using an actual example of a production line for electronic devices.     

高线精轧机在线监测系统研究

湘潭钢铁集团第二高线厂的高线生产是公司生产的重要环节,保证高线设备的稳定运行对于整个高线生产有着重要意义。高线设备采用在线状态监测系统对机械设备运行状态进行实时振动监测和故障分析,从而可以获得机械设备的实时运行状态数据,对设备运行状况及发展趋势做出科学评价,并对一些重要参数实现超限报警。     

数据流链接技术在军用维修物资编码系统中的应用

本文从军用维修物资业务管理的角度,讲述了军用维修物资的分类体系;从军用维修物资信息管理的角度,讲述了军用维修物资的信息分类;从计算机数据处理的角度,讲述了数据流链接技术在军用维修物资编码系统中的应用,并给出了其应用程序流程.     

数字城市建设中的数据问题

本文首先指出了数据在数字城市建设中的重要作用 ,描述了数字城市建设中需要的数据。当前存在的问题是 :数据陈旧匮乏 ,缺乏标准规范 ,管理封闭混乱 ,数据存储、传输、处理技术发展滞后 ,数据商业化、市场化、产业化步履艰难。因此 ,必须采取若干对策 ,如健全法律法规 ,完善标准规范 ,理顺投资收益关系 ,加速数据技术开发和数据中心建设 ,完善数据管理体制 ,建立数据采集、更新、共享、交流、安全保密机制 ,推进商业化和市场化。     

Regional Unemployment in Transitional China: A Theoretical and Empirical Analysis

The purpose of this paper is to explain the pattern of regional unemployment in transitional China. A model is developed to explore how urban unemployment in the provinces is influenced by peasants' wages, formal sector wages, and the size of the formal sector. Evidence from panel data suggests that a significant indicator of high unemployment rates is greater Urban–Rural Income Inequality within the province. The hypothesis is that the urban–rural income gap produces migration, and more rural migrants substitute for urban workers, causing further urban unemployment.Since the economic reforms began in 1978, the non-state owned enterprises have been carrying an increasing weight in the economy, and they have contributed significantly to the rapid economic growth of China. Empirical evidence shows that economic reforms have reduced unemployment. The provinces that are still heavily dependent on the state sector are therefore more likely to experience higher unemployment.