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1.
ETRⅠ-30调速器是瑞士爱舍维斯工厂生产的具有PID调节规律的电液调速器。本文对其液压控制系统作了较详细的介绍,供有关人员参考。  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 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   
4.
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   
5.
In this article, the finite element solution of quasi-three-dimensional (quasi-3-D) groundwater flow was mathematically analyzed. The research shows that the spurious oscillation solution to the Finite Element Model (FEM) is the results choosing the small time step ?t or the large element size L and using the non-diagonal storage matrix. The mechanism for this phenomenon is explained by the negative weighting factor of implicit part in the discretized equations. To avoid spurious oscillation solution, the criteria on the selection of ?t and L for quasi-3-D groundwater flow simulations were identified. An application example of quasi-3-D groundwater flow simulation was presented to verify the criteria. The results indicate that temporal discretization scale has significant impact on the spurious oscillations in the finite-element solutions, and the spurious oscillations can be avoided in solving practical quasi-3-D groundwater flow problems if the criteria are satisfied.  相似文献   
6.
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   
7.
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   
8.
A simi-implicit finite element method is developed for three-dimensional shallow water flow. By using water depth to scale the vertical coordinate, the governing equation is transformed into fixed computational domain. An efficient generalized conjugate gradient scheme is adopted for the solution of finite element analogy.  相似文献   
9.
NUMERICALSTUDYOFTURBULENTJETSCONFINEDBETWEENTWOCONCENTRICSPHERESZhangGuang-hua;TangGe-feng(TsinghuaUniversity,Beijing,100084,...  相似文献   
10.
水工钢筋混凝土结构三维配筋CAD系统的方案及其实现   总被引:3,自引:0,他引:3  
本文针对三峡工程中大量的钢筋混凝土结构的配筋设计问题,分析了配筋设计绘图的特点,提出了三维可视化配筋设计方案,研究了系统实现的部分技术问题.该方案的原型系统已基本完成,即将应用于实际配筋设计.最后结合系统的应用示例,介绍了系统的功能特色  相似文献   
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