股票收益与交易量的动态关系研究来自不同估计方法的证据

本文采用三种面板数据方法（加总时序、混同和组平均）考察中国股票收益和交易量的动态关系,以期揭示由于系数异质性问题,建立在三种方法上的统计推断可能会产生矛盾。结果表明,混同和组平均都发现了收益和交易量间双向的格兰杰因果关系,交易量对未来收益的长期影响显著为负;这与投机泡沫理论的预示相符。而加总时序方法只能发现收益对交易量的单向引导。     

一种基于帧中继的多路语音编码芯片的研究

本文在介绍AudioCodes公司的AC4804A-C芯片的基础上，着重于研究该芯片的应用，并给出了应用结果。     

The geographical efficiency of Spain's regional airports: A quantitative analysis

Previous studies of the role of regional airports in the Spanish economy have focused on calculating efficiency using air traffic as the output and airport infrastructure data as the input. We present an alternative quantitative analysis based upon the geographical structure within the airport's market basin. We formulate a ‘geographical efficiency’ model that considers territorial variables within the airport hinterland. Input data for our model include the socio-economic structure of the population, intermodal transport links, industrial and tourism potential and existing leisure-related services. The output is the annual number of passengers associated with such constraints. The result is a relative efficiency estimate that shows uneven patterns of geographical efficiency amongst Spain's regional airports and also provides insights into opportunities for expanding some of these critical items of infrastructure. They suggest that some of Spain's regional airports may be better placed than others to compete in a liberalized market that exhibits a clear tendency in favor of coastal, tourism-based airports.     

Operational performance evaluation of international major airports: An application of data envelopment analysis

This paper uses data envelopment analysis to assess the operational performance of 20 major airports around the world. It is found that the form of ownership and the size of an airport are not apparently correlated with operational performance of airports. In contrast, the existence of a hub airport, the location of the airport, and the economic growth rate of the country in which the airport is located are all related to the operational performance of airports. The 20 airports are put into four groups according to their efficiency values.     

地市级部门网络建设和规划

通过分析地市级部门网络布线、网络拓扑结构、网络安全实现和数据存储等方面的需求,依据金华市气象局网络建设经验,对地市级部门网络建设和规划提出一定的建设性意见,对保障各项网络业务的正常运行提供一定参考。     

SUPPLIER EVALUATION IN A DYADIC RELATIONSHIP: AN ACTION RESEARCH APPROACH

This article describes an Action Research (AR) framework applied to the supplier evaluation environment of a telecommunication company. Within this AR framework, data envelopment analysis (DEA) was used because the methodology can successfully delineate evaluation problems and then outline a desirable path. This leads management to continuously review and improve complex systems or processes. The DEA methodology coordinates the supplier evaluation inputs and reconciles what can be very diverse performance measures and even more diverse weights applied by evaluation team members. Finally, dyadic interdependence can be demonstrated by identifying the impact of changes in buyer performance attributes on each supplier's capacity to accommodate and adjust.     

一种高速移动衰落信道的特性与分析

高速移动信道不同于一般的移动信道，其速度影响亦不可忽视，本文分析了高速移动信道的特性，提出了信道模型，并进行了性能分析。     

基于电子信用卡网上支付的安全电子交易（SET）协议的研究

安全电子交易协议是电子商务中基于信用卡支付系统最典型、最常用的国际标准,该协议定义了客户、商家、支付网关及金融机构之间数据的流通过程,并对这些信息流都采取了数字加密及数据认证技术,以此确保网上交易的安全。但它过于繁杂的程序使得系蔓号承粤过重的负载,这个问题如今越来越引起了专家们的关注,并成为未来研究改进的重点。