谈桥梁裂缝在道桥工程中的影响

本人结合多年参与公路桥梁现场施工工作实践,对部分桥梁在建设过程中常见的一些裂缝类型进行归类总结,通过查找原因分析问题,才能让我们真正地了解各种裂缝的引发成因,进而制订防范措施,达到预防布控之目的。     

Income distribution dynamics of urban residents: The case of China (1995–2004)

Using a 1995–2004 panel data of Chinese urban residents, we investigate the dynamics of income distribution in cities. According to Kernel estimates of the relative income distribution of Chinese cities, we find that: (1) the national across-city distribution of per capita GDP exhibits an apparent unique-peak distribution in 1995 and an “emerging multiple-peak” one in 2004; (2) for prefecture-level cities, income distribution has evolved to an “apparent multiple-peak” distribution from a unique-peak one; (3) the income distribution of county-level cities maintains a unique-peak curve; (4) most of the income dynamics of urban residents originates from prefecture-and-higher-level cities. We sample three representative provinces and study the urban income dynamics respectively. The analysis suggests that within a single province, urban income distribution evolves from unique-peak to twin-peak curve; while among provinces, income convergence is evident for urban residents. In addition, we measure the incidence of poverty in cities based on our income dynamics analysis, and find that the ratios of people living below absolute poverty line have been decreasing at cities of all levels.     

基于PCAIDS模型的单边价格效应模拟——以国际铁矿石巨头力拓与必和必拓拟议的兼并为例

本文基于爱泼斯坦和鲁宾菲尔德提出的PCAIDS 模型,模拟了国际铁矿石生产和出口巨头力拓与必和必拓之间2007 年10 月提出的兼并的单边效应.研究发现,该兼并对世界铁矿石市场价格将产生重要影响,特别是兼并后形成的新企业将大幅度提高其产品的价格.兼并也会引起印度、巴西和南非铁矿石提价,尽管幅度要比"两拓"要小一些.中国的进口铁矿石主要来自于两拓、巴西、印度和南非,因此,如果"两拓"兼并将极大地提高我国进口铁矿石的成本.     

Brain drain and factor complementarity

In this paper we develop an extended Solow growth model with emigration which aggregates different types of labor skills from strict complementarity to perfect substitution. The derivation of balanced growth paths shows that the most relevant cases for studying the impact of emigration are those where these paths can only be attained asymptotically. This requires and justifies the need for using transitional dynamics. We therefore derive a complete characterization of the transitional dynamics of output and wages in the sending country for all possible values taken by the elasticity of substitution between skilled and unskilled workers. The model then serves to qualitatively study the effect of brain drain on per capita income and wages of the sending country.     

对低碳经济热的冷思考

按照我国发展低碳经济的路线图,电力、交通、建筑、钢铁、水泥、化工及石油化工六大部门的排放占到我国工业排放的70%、全国排放的50%。世界资源研究所筛选了88种技术,至少有60种技术作为骨干支持的路径,否则,实现低碳经济就是一纸空文。     

结合机械设计教学开展多种形式计算机辅助设计

本文介绍作者多年来结合机械设计教学开展计算机辅助设计几种行之有效的形式。     

我国中小商业银行资本充足率问题比较研究

随着新巴塞尔协议的不断补充和完善,我国商业银行的资本充足问题又成为我国经济体制改革中的热点问题。本文通过对资本充足性和资产结构理论的分析,运用多元回归的分析方法对我国中小商业银行的资本充足问题进行研究,并与香港商业银行资本充足状况进行对比;根据实证分析的结果,对我国中小商业银行资本补充问题提出提高盈利水平、清理和重估固定资产,谨慎对待表外业务的对策。     

国外社会保障税制及其对我国的启示

社会保障税已被许多国家所采用并作为国家社会保障体系中主要的资金筹措手段。研究国外社会保障税制,对我国构建社会保障税制度启示良多。     

大力发展中国奢侈品产业

什么是奢侈,什么是奢侈品,应该发展奢侈品行业吗 ？奢侈是一种原罪,还是进步的动力 ？--当欲望在引领全球,刚刚走上小康之路的中国人是应该反对奢侈还是应该发展奢侈呢 ？ 当市场经济逐渐成为全球共同价值观,而经济增长越来越依赖于对消费欲望的刺激时,我们不禁会产生上述疑问.     

中国国际收支结构的变迁及启示

本文通过对1982～2004年间中国国际收支一级账户结构、次级账户结构和差额平衡结构的考察发现:中国国际收支结构的发展历程带有明显的政策烙印;“双顺差”的形成和发展具有相当的可持续性;正在进行的人民币汇率机制改革短期内对国际收支结构难以发挥显著的作用,长期来看影响深远。