基于模态应变能密度理论的网架结构损伤识别方法

为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。     

Will China's WTO accession worsen farm household incomes?

Many fear China's accession to the World Trade Organization (WTO) will impoverish its farmers via greater import competition in its agricultural markets. We explore that possibility bearing in mind that, even if producer prices of some (land-intensive) farm products fall, prices of other (labor-intensive) farm and nonfarm products could rise. New estimates, from the global, economy-wide numerical simulation model known as Global Trade Analysis Project (GTAP), of the likely changes in agricultural and other product prices as a result of WTO accession, are drawn on to examine empirically the real income implications of China's WTO accession. The results suggest farm–nonfarm income inequality may well rise within China but rural–urban income inequality need not. The article concludes with some policy suggestions for alleviating any pockets of farm household poverty that may emerge as a result of WTO accession.     

信息技术提高企业组织敏捷性的作用机理

从考察企业组织的敏捷性与交易成本的相互关系入手,对企业组织敏捷性的影响因素进行了剖析。详细分析了信息技术(IT)对提高企业组织敏捷性的作用机理。指出IT正是通过降低企业内、外部的交易成本、缩短流程时间、提高人的认识理性、扼制机会主义、促进企业组织结构、决策方式     

我国旅游地区收入分析及对策探讨

旅游收入是旅游经济活动的重要内容，它一方面反映了旅游者的旅游需求通过旅游经营者的旅游供给而不断得到满足，另一方面又体现着旅游产业部门和企业在产经营活动的价值运行与价值实现。旅游收入与分配是旅游经济运行的前提，对其进行考察分析，是十分重要的。本章从收入和分配两个方面入手，对旅游收入分类、指标、旅游企业收入和分配以及旅游收入乘数的作用等进行了分析和阐述。     

民营企业发展的金融支持

文章首先回顾了民营企业融资研究的有关成果.其次,详细分析了目前我国民营企业存在的金融约束.最后,尝试给出了一些建议以加强对民营企业的金融支持.     

Debt Issue Costs and Issue Characteristics in the Market for U.S. Dollar Denominated International Bonds

This paper analyzes the issue costs and initial pricing of bonds in the international market. In particular, we investigate the determinants of three components of issue costs: underwriter fee, underwriter spread (the difference between the offering price and the guaranteed price to the issuer), and underpricing (the difference between the market price and the offering price). Total underwriter compensation increases with the bonds' credit risk and maturity, but it is insignificantly related to issue size. Interestingly, underwriters appear to price some issue characteristics directly (by adjusting the fee) and other characteristics indirectly (by setting the guaranteed price). The two compensation components (fee and spread) are negatively related to each other. We provide evidence that this trade-off is consistent with income tax considerations, as well as with two-tier pricing by underwriters. We find no evidence of underpricing.     

构造信贷市场资金价格形成机制分析——对定南县贷款利率市场化改革的个案研究

文章通过对江西定南县利率改革试点进行个案研究，从宏观和微观两个层面探讨了如何构造信贷市场资金价格形成机制。     

Intraday Lead-Lag Relationships Between the Futures-, Options and Stock Market

In rational, efficiently functioning and complete markets, returns on derivative and underlying securities should be perfectly contemporaneously correlated. Due to market imperfections, one of these markets may reflect information faster. The use of high-frequency data and the choice for a small unit time interval to measure these lead-lag relations comes at the cost of some or many missing observations, causing traditional estimators to either under- or overestimate covariances and correlations. We use a new estimator to estimate lead-lag relationships between the cash AEX index, options and futures. We find that futures returns lead both options and cash index returns by approximately 10 minutes. The relationship between options and the cash market is not completely unidirectional.     

Programme Evaluation with Unobserved Heterogeneity and Selective Implementation: The Mexican PROGRESA Impact on Child Nutrition

This paper considers the impact of Programa de Educación, Salud y Alimentación ( PROGRESA ), a large Mexican rural anti-poverty programme that had an evaluation sample in which overall treatment was randomly assigned to some communities but not others, on child nutrition. When we examine the impact of PROGRESA based on the presumption of randomized allocations, we find that PROGRESA had no or even a negative impact on child nutrition. However, not all children designated to receive nutritional supplements actually did so. Our preferred estimates – child fixed-effects estimates that control for unobserved heterogeneity that is correlated with access to the supplement – indicate a significantly positive and fairly substantial programme effect of the nutritional supplements on children 12–36 months. They imply an increase of about a sixth in mean growth per year for these children and a lower probability of stunting. Effects are somewhat larger for children from poorer communities but whose mothers are functionally literate. The long-term consequences of these improvements are non-trivial; its impact working through adult height alone could result in a 2.9% increase in lifetime earnings.