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1.
Within the UK there has been a lack of studies of technical efficiency at the Scottish level. This note compares the results obtained using Scottish data with a recent study by Hadley [Journal of Agricultural Economics (2006) Vol. 57, pp. 81–100] for English and Welsh farms. Four major sectors are investigated, namely: (i) cereals, (ii) dairy, (iii) sheep and (iv) beef over the period 1989 to 2004. Some distinct differences in efficiencies, returns to scale and causes of efficiency are found.  相似文献   
2.
I examine the effect of different forms of foreign investment liberalization on risk in emerging equity markets, including international cross-listings and closed-end country funds, and in the domestic equity market as foreign investment restrictions are eliminated. I find that in Latin American markets volatility declines significantly with different forms of foreign investment liberalization, and in Asian markets volatility does not increase significantly. Volatility is driven by domestic factors in South America, but the transmission of volatility from the United States to Mexico increases after liberalization. The market risk exposure increases in Argentina after liberalization, in Chile with an index of American Depositary Receipts, and in Thailand with greater foreign ownership, reducing the diversification benefits of these markets.  相似文献   
3.
We examine investment behavior among exchange-listed Korean manufacturing firms before and after the 1997 financial crisis using firm-level panel data. Starting with the standard Q-theory of investment, we augment it by allowing for a sales accelerator and the possibility of cash constraints, categorizing firms based on their age, size and affiliation to an industrial conglomerate (i.e., chaebol). We find that Tobin’s Q is a robust determinant of investment in a pooled sample for 1992–2001, but that it became more important for small firms and less important for chaebol-affiliated firms after the crisis. Investment by chaebol firms also became more sensitive to the availability of internal cash balances after the crisis. We interpret this as reflecting a shift in the Korean economy to a stronger market orientation after the crisis and to a business climate in which the quality of potential projects became more important relative to capital market imperfections in determining the destination of investment funds.  相似文献   
4.
Cr3+-H3PO4光度法测定磷酸体系中的Cr3+   总被引:1,自引:0,他引:1  
Cr3 与H3PO4生成绿色配合物,其最大吸收峰在660nm,摩尔吸光系数为1.4×102L·mol-1·cm-1,Cr3 在0~0.5mg/30ml范围内符合比尔定律,用加入法直接测定磷酸体系中的Cr3 ,结果满意。  相似文献   
5.
We examine whether favorable information conveyed by stock split announcements transfers to nonsplitting firms within the same industry. On average, nonsplitting firms' shareholders experience positive and significant abnormal returns at the stock split announcements of their industry counterparts. In addition, industrywide and firm-specific characteristics are important determinants in explaining nonsplitting firms' stock returns. These firms' earnings increase significantly, and the earnings changes are positively related to the stock price reactions. Finally, we find no evidence that investors revise the value of nonsplitting firms because they anticipate a decline in earnings volatility.  相似文献   
6.
We examine the spillover wealth effects of the Orange County, California bankruptcy announcement in December 1994 on municipal bonds, municipal bond funds, and bank stocks. This bankruptcy is prominent because of unprecedented losses and because it was caused by a highly leveraged derivatives strategy rather than a shortage of tax revenues and excess spending. We find contagion in the bond market with significantly negative abnormal returns for municipal bond funds without direct exposure to Orange County and for non‐Orange County municipal bonds. In addition, our findings suggest the contagion spills over to the common stocks of investment and commercial banks that deal in or use derivatives; however, the equities of banks unexposed to derivatives are not affected.  相似文献   
7.
本文通过对新装置条件下位场特征的分析,应用边界单元法及解析法的计算结果,发现当二维或三维电性不均匀体与测量电极位于背景场同一等位面时,视电阻率异常反映最明显。从而提出了圆弧交会法确定二维或三维地电体中心理深的方法,并给出了若干计算实例。结果表明,此方法简便有效且精度较高。  相似文献   
8.
设计了系统的基本思路,在Visual Studio 2008数据库的基础上,利用OpenGL对矿山巷道,硐室设计等进行三维可视化虚拟,并通过数学模型,对矿井设计进行分析与纠错处理,用C#实现系统的功能。  相似文献   
9.
以高西沟露天煤矿的西北边帮作为研究对象,运用FLAC3D数值模拟软件,经过数值计算得到边坡安全系数为1.57,其与工程类比法计算得到的数值差不多,知该数值分析方法不仅能快速、准确的算出边坡的稳定性系数,还能够形象的描绘边坡的滑移临界场,是一种有效的边坡稳定性分析的方法。  相似文献   
10.
3G时代移动互联网展望   总被引:3,自引:0,他引:3  
谢萌 《科技和产业》2009,9(3):75-76
移动通信具有可移动性这一鲜明特点,互联网则是现今信息传播的最重要载体,移动通信与互联网结合产生移动互联媒体,这将是现在乃至未来一段时期内通信的发展趋势。本文将围绕中国移动互联网的现状和发展以SWOT的方式进行讨论,并简要分析。  相似文献   
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