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41.
辽河干流堤防安全泄量为5000m3/s,盘锦城市防洪工程竣工后,其安全泄量为6800m3/s。而盘山闸的设计泄流能力仅为3000m3/s。通过本模型试验研究进一步确定扩建工程方案的合理性。 相似文献
42.
变权组合预测模型在大坝安全监测中的应用 总被引:1,自引:1,他引:0
简要介绍了组合预测模型的基本原理,该模型改进了单一模型考虑因素的片面性,但常规的组合预测模型的权系数是固定的。考虑到各种模型的预测精度的变化,以及大坝安全监测数据存在的突变、时效等因素,固定权系数的组合预测模型有待进一步改进。文中提出了变权系数组合预测模型,并将其用于实际的大坝安全监测工程。结果表明,变权组合预测模型的预报精度高于其他模型。是一种值得推广的方法。 相似文献
43.
Tan Guang-ming Wang Zhen-zhong Wuhan University of Hydraulic Electric Engineering Wuhan P.R.China 《水动力学研究与进展(B辑)》1992,(1)
It is mentioned in this paper that the adjustment of flow structure occurs when themain-flow swings.The changes of turbulence structure and flow energy loss in the indoor rivermodel are measured.The experimental data are presented for the first time for the further studyof complicated river flow structure. 相似文献
44.
利用面板数据对中国东、中、西部的进口额和GDP增长关系进行的实证研究。在短期内,GDP增长对进口额影响最小是中部地区,在长期,西部GDP增长对进口额影响最大。中国经济增长对拉动世界经济增长起了十分重要的作用,中国经济增长减速也会影响全球经济。 相似文献
45.
试论我国证券投资基金稳定市场的功能 总被引:1,自引:0,他引:1
本文采用博弈分析方法 ,通过博弈模型 ,对虚假会计信息产生的条件、机制和影响因素等作了探讨。 相似文献
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48.
China's Regional Disparity and Its Policy Responses 总被引:3,自引:1,他引:2
Minjia Chen Yongnian Zheng 《中国与世界经济(英文版)》2008,16(4):16-32
The fruits of China's rapid economic development over the 3 decades have not been distributed fairly across different regions. Using data from a sample of 815 Chinese listed firrns during 1998-2004, our error-correction investment model showes evidence of different financial constraints on firms' investment in different regions. We argue that China's regional development policies have contributed greatly to the regional inequalities. To control the rising inequality, China has shifted its focus from the coast to the interior regions. However, it is becoming increasingly difficult for the government to direct the economy, as market mechanisms now have afar greater influence on the economy than the government does. The people-centered approach of the current leadership has meant that substantial attention has been placed on regional development disparities in an attempt to build a "harmonious society. " China needs further extensive reforms if all the measures for reducing regional disparity are to be effective. 相似文献
49.
This paper utilizes a Ricardian model to test the relationship between annual net revenues and climate across Israeli farms. The study finds that it is important to include the amount of irrigation water available to each farm in order to measure the response of farms to climate. With irrigation water omitted, the model predicts climate change is strictly beneficial. However, with water included, the model predicts that only modest climate changes are beneficial while drastic climate change in the long run will be harmful. Using the AOGCM Scenarios we show that farm net revenue is expected to increase. Although Israel has a relatively warm climate a mild increase in temperature is beneficial due to the ability to supply international markets with farm product early in the season. 相似文献
50.
In horticultural markets, trade barriers often apply to the processed products whereas domestic support applies to farm-produced raw commodities. Here we assess the effects of such trade barriers and domestic support by simulating the effects of policy reform on global processing tomato markets, which are faced with modest processed product tariffs and high domestic support in the European Union (EU). Both protection and EU subsidy drive down world welfare, but we find that reducing import tariffs for tomato products would yield greater effects on markets and larger welfare impacts outside Europe than would reductions in EU domestic support. 相似文献