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141.
本文叙述了应用现代科学方法和实验原型观测技术对新安江水电站进水口快速闸门进行安全检测鉴定,并介绍了水电站快速闸门动水闭门试验程序,对水电站快速闸门试验及相关鉴定有重要参考意义。  相似文献   
142.
This paper presents the case for and the evidence in favour of passive investment strategies and examines the major criticisms of the technique. I conclude that the evidence strongly supports passive investment management in all markets—small–capitalisation stocks as well as large–capitalisation equities, US markets as well as international markets, and bonds as well as stocks. Recent attacks on the efficient market hypothesis do not weaken the case for indexing.  相似文献   
143.
The present paper was inspired by and is a response to the Rola-Rubzen, Hardaker and Dillon paper 'Agricultural economists and world poverty: progress and prospects' (Rola-Rubzen et al. 2001). It is agreed that the position of agricultural economists in foreign aid and poverty programs has declined over recent decades. Such a feeling of guilt and remorse expressed by the above authors does indeed create considerable 'angst'. A major reason for this state of affairs lies in 'the flavour of the month' approach of the development agencies. These include women in development, gender-based farming systems research, household nutrition and food security, people participation, and targeting the poorest of the poor. These fads have driven disciplinary considerations to the wall and the more widely-defined objectives have reduced the drive for economic efficiency. We argue there is still a place for better designed and delivered assistance programs within the wider framework of assistance that has become fashionable. Greater application of institutional principles in both the political processes associated with assistance and the implementation agencies would improve the outcomes of many projects. Particular attention would need to be given to the interface between the development agencies and recipient governments. The present paper picks up on the market failure aspects of agriculture's rather poor contribution to development, and develops a wider perspective in terms of the new institutional economics and a continuing role for the agricultural economist.  相似文献   
144.
145.
Major tax reform to simplify the UK tax system is possible. Merging income taxes, social security taxes and corporation tax into only a single flat-rate of tax on all incomes would be a radical start. Avoiding taxes on income and expenditure which are 'too high' requires major reductions in government spending, mainly on the welfare state. Given the political will, over a period of years we really can hugely improve the UK tax system.  相似文献   
146.
Lake Chivero: A management case study   总被引:1,自引:0,他引:1  
Lake Chivero in Zimbabwe was shown to be hypereutrophic. Historical data showed that the eutrophication process had been arrested in the late 1970s. However, a combination of poor planning, multiplicity of jurisdiction, mismatch between rate of urbanization and waste management investment, recent changes in the local climate and a permissive, immature political system that called for no public accountability resulted in environmental management breakdown leading to hypereutrophication of the lake. The case of Lake Chivero is presented as an example of a wider global issue regarding the status of environmental management in competition with other priorities in emerging democracies.  相似文献   
147.
The decline in private health insurance coverage over the period 1989–95 is analysed using the ABS National Health Surveys. Individuals' health status and health risk behaviours are found to be significant determinants of their decision to purchase private health insurance. At a point in time, the pool of the insured is very heterogeneous, with a mix of both good and bad health risks. It is found that the decline in insurance coverage over the period 1989–95 coincided with an increase in the degree of 'adverse selection' within the insured population.  相似文献   
148.
Operation of the dam in a transitional mode is described. __________ Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 1, January 2006, pp. 8–15.  相似文献   
149.
150.
Exploring the Intensive and Extensive Margins of World Trade   总被引:1,自引:0,他引:1  
World trade evolves at two margins. Where a bilateral trading relationship already exists it may increase through time (intensive margin). But trade may also increase if a trading bilateral relationship is newly established between countries that have not traded with each other in the past (extensive margin). We provide an empirical dissection of post–World War II growth in manufacturing world trade along these two margins. We propose a “corner-solutions version” of the gravity model to explain movements on both margins. A Tobit estimation of this model resolves the so-called “distance puzzle”. It also finds more convincing evidence than recent literature that WTO-membership enhances trade. JEL no. F12, F15  相似文献   
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