Economic returns to speaking ‘standard Mandarin’ among migrants in China's urban labour market

This article uses data from the China Urban Labour Survey administered across 12 cities in 2005 to estimate the economic returns to speaking standard Mandarin among internal migrants in China's urban labour market. The article builds on studies that estimate the economic returns to international immigrants of being fluent in the major language of the destination country and studies that estimate the economic returns to proficiency in the national language among groups of people who speak a minority language. Importantly, we control for potential endogeneity bias in the estimates of the effect of language fluency on earnings. We find that for migrants as a whole, there are considerable economic returns to speaking standard Mandarin. We also find gender differences. While the coefficient on fluency in standard Mandarin is statistically significant and large for females, the coefficient on fluency is statistically insignificant for males. One possible explanation for this finding is that female migrant workers are engaged more in occupations which have greater contact with urban locals and hence the return to investment in language skills is higher.     

基于IEC61850的变电站自动化系统研究

随着非常规互感器逐步在工程中代替传统电磁互感器运行,IEC 61850标准的颁布及其对信息的统一建模,高速以太网技术构建的变电站数据采集及传输系统的应用、智能化断路器技术的发展等,使得数字化变电站及数字化电网概念正被逐步提出。     

浅议领导者的用人艺术

选才用人,对领导者来说是一个重要的职责,是领导者的一个重要的能力。而领导者的用人恰当与否,则直接关系到事业的兴衰成败。正因为人才是事业兴衰之根本,因此领导者要成就事业．就必须树立科学的用人观,掌握高超的用人艺术．     

基于IAP15F2K61S2单片机的车载酒精智能报警系统设计

针对传统51单片机外围电路复杂,缺少灵活性等缺点,采用最新的IAP15F2K61S2单片机作为控制核心,设计了一种车载酒精智能报警系统.该系统采用双重检测方式通过对驾驶员呼出气体酒精浓度的检测来控制汽车的启动,同时具有语音报警、GSM短信提示、温度时间显示等功能.     

主题图的概况及应用研究（上篇）

在语义Web时代,主题图（TopicMaps,文章简称TM）被认为是实用性较高的知识组织技术。本研究以TM技术的应用为最终目标,分上、下两篇整体地论述TM的相关研发工作。本篇中给出TM的概况,包括TM的概念、标准体系、应用领域、开发工具和相关网站等,为进行具体领域的应用开发奠定了基础;在另一篇中,将结合金融培训机构知识体系,介绍如何应用TM技术来组织行业知识,包括基于TM技术的金融培训机构知识系统的架构设计和实现。最后,给出本研究对未来的展望及结论。     

Efficiency,technology and productivity change in Australian universities, 1998–2003

In this study, productivity growth in 35 Australian universities is investigated using non-parametric frontier techniques over the period 1998–2003. The five inputs included in the analysis are full-time equivalent academic and non-academic staff, non-labour expenditure and undergraduate and postgraduate student load while the six outputs are undergraduate, postgraduate and Ph.D. completions, national competitive and industry grants and publications. Using Malmquist indices, productivity growth is decomposed into technical efficiency and technological change. The results indicate that annual productivity growth averaged 3.3% across all universities, with a range from −1.8% to 13.0%, and was largely attributable to technological progress. However, separate analyses of research-only and teaching-only productivity indicate that most of this gain was attributable to improvements in research-only productivity associated with pure technical and some scale efficiency improvements. While teaching-only productivity also contributed, the largest source of gain in that instance was technological progress offset by a slight fall in technical efficiency.     

Communication service model for wide area protection system based on IEC 61850

In order to meet the requirements of information exchange varieties and manners in wide area protection system, a communication service model based on IEC 61850 is proposed. This service model can realize communication consistency and cooperation between different types of devices. Furthermore, the communication reliability and time delay performance are guaranteed to meet the requirements of relay protection from the upper layer. Message structure of generic substation event (GSE) and its communication mechanism are discussed. General methods to communicate digital information by generic substation status event (GSSE) and communicate analog sampling information by sampling analog value (SAV) of GSE are proposed.     

An analog front-end circuit for ISO/IEC 15693-compatible RFID transponder IC

INTRODUCTION The rapidly increasing application of radio fre- quency identification (RFID) includes supply chain management, access control to buildings, public transportation, airport baggage, and express parcel logistics (Karthaus and Fischer, 2003; Feldhofer, 2004; Glidden et al., 2004). Using an RFID system is a good approach for automated identification of products. RFID system consists of two major components, an interrogator (reader) and a transponder (tag), composed of an ant…     

实验室质量体系ISO/IEC导则25:1990到17025:1999的转换

中国实验室国家认可制度全面实施了从ISO／IEC导则25：1990到ISO／IEC17025：1999的转换，本文结合实际的质量体系转换经验，分析了对于ISO／IEC17025：1999的特点的理解，给出了实验室质量要素和程序文件在不同标准中的对应和转换关系，并提供了质量体系建立和转换工作中的步骤和方法。本文可以为其他同类实验室完成质量体系的转换工作提供参考。     

用UML和XML建模语言开发故障信息处理系统

简单介绍了电网故障信息处理系统的基本功能以及现状,探讨了最新标准IEC61850以及统一建模语言UML和可扩展标记语言XML在故障处理系统开发中的应用.