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161.
本文从分析帷幕灌浆设计入手,着重介绍了帷幕灌浆施工工艺和质量检查;通过测试数据对灌浆效果进行了评价分析,认为通过大坝中热水泥高压灌浆,河床坝基幕体已基本形成。 相似文献
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设计阶段的建设项目工程造价的控制是建设项目在做出投资决策后的控制重点,设计阶段是建设单位工程造价控制的关键和重点。阐述了建设单位加强设计阶段工程造价控制的意义以及采取的主要措施。 相似文献
164.
Su Zhou 《Applied economics》2013,45(7):849-856
Earlier studies hardly reject the hypothesis of a unit root in inflation. Few studies have examined the possibility of nonlinearity in inflation and tested nonlinear stationarity of the inflation rates. This study thus intends to fill the gap. This study utilizes the tests for nonlinearity along with the unit root tests that allow for nonlinearity in the variables to examine the stationarity of inflation rates of 12 European countries that formed the Euro Zone (EZ) later in the sample period. The results suggest that the majority of these countries’ inflation rates can be characterized by mean reversion during the floating exchange rate period. Many of them appear to be nonlinear stationary. This finding is essential in conducting applied economic studies for these countries, when constructing models whose validity relies on whether or not inflation is stationary. The results of this study also imply that shocks to inflation have a transitory effect on inflation in the euro area. Therefore, it would be less costly in exercising the policies of disinflation for the monetary authorities of the euro area than for those of the countries with nonstationary inflation. 相似文献
165.
四龙水电站水轮发电机组处理与安装 总被引:1,自引:0,他引:1
介绍了上思县四龙电站水轮发电机组的基本情况,论述了安装过程中碰到的问题,和所采取的处理措施和安装工艺。对立式小型水轮发电机组的安装和检修,有一定的借鉴作用。 相似文献
166.
Manolis G. Kavussanos Amir H. Alizadeh-M 《Transportation Research Part E: Logistics and Transportation Review》2001,37(6):561
This paper investigates the nature of seasonality (deterministic and/or stochastic) in dry bulk freight rates, and measures and compares it across freight rates of different vessel sizes (Capesize, Panamax and Handysize), contract duration (spot, 1-year and 3-year time charters) and market conditions (peaks and troughs). Although, there is no evidence of stochastic seasonality, deterministic seasonality in freight rates is found to be varying from −18.2% to 15.3% in individual months within a year. Spot rates for larger vessels exhibit higher seasonal fluctuations compared to smaller vessels, although differences in seasonal fluctuations between sectors are eliminated as the contract duration increases. Also, for each vessel size, the seasonality declines as the contract duration rises. Asymmetries in seasonal fluctuations in freight rates over different market conditions are attributed to the high and low elasticities of supply expected under the respective market conditions. The results have implications for tactical shipping operations such as timing of dry-docking, chartering strategies and switching between freight markets. 相似文献
167.
We develop a typology of corporate venture units, based on their strategic role in the corporation, and specifically on (a) their relative emphasis on exploration versus exploitation and (b) the internal versus external locus of opportunity they pursue. Following configurations logic, we argue that the structures and systems used by venture units will be a function of their strategic role, and that their performance will be higher when internal elements are aligned. We also argue that exploitation-oriented units will survive for longer than exploration-oriented units. Using primary data collected on 95 venture units during 2001–2003, we use configurational analyses to test and find support for our hypotheses. 相似文献
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广蓄二期工程抽水蓄能机组的振动评估 总被引:1,自引:0,他引:1
抽水蓄能机组的运行工况复杂,其振动问题较之常规水轮发电机组更引起人们的关注。为了解广蓄二期抽水蓄能机组的振动特性以保障其安全运行,在机组上配置了振动监测系统,它包括机组振动保护和振动分析两大系统。该系统可以监测顶盖、各部轴承、上机架等处的振动速度与大轴摆度。根据广蓄二期机组的实测数据,参照国家标准化组织ISO提出的水轮机振动限制曲线和评估标准,评估其运行稳定性和振动特性,均达到ISO相关标准的A区好水平。 相似文献
170.
对GB/T18482-2001《可逆式抽水蓄能机组启动试验规程》修订的主要内容和重大问题进行分析、介绍,以期在使用中更好地发挥国家标准的指导作用。 相似文献