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151.
长期以传统GDP作为衡量经济发展的单一评价指标,造成了一系列环境问题,已不能满足科学发展观的要求.以绿色经济为视角,通过计量方法重新计算包含环境成本的相对绿色GDP,发现环渤海地区除北京市以外,在经济总量扩张的同时环境压力不断增加.将计算得到的相对绿色GDP作为DEA- Malmquist模型的产出指标,重新评价环渤海地区的经济效率,发现新的效率值明显低于传统GDP下的经济效率,并有不断下降的趋势. 相似文献
152.
Mining projects are complex businesses that demand constant risk assessment. This is because several kinds of uncertainties influence the value of a mine project, typically. These uncertainties may be classified as exploration uncertainties, economic uncertainties and engineering uncertainties. The evaluation of a mine project under these uncertainties is a complicated job, which may lead to making a wrong decision by managers and stockholders. Therefore, at first, the engineers must recognize the mining uncertainties before carrying out the project evaluation. The economic uncertainties are the most important factors, which may affect the project evaluation. Among the mentioned uncertainties, the operating cost uncertainty is an important and effective factor, which is ignored to a certain extent. 相似文献
153.
Sergio Alvarez 《Journal of Environmental Planning and Management》2016,59(12):2145-2162
Increased trade and human mobility result in sizable benefits to society, but are often accompanied by negative consequences, such as increased introduction of invasive pests to different landscapes and seascapes. In this paper, we couple an existing model of the biological spread of Nasutitermes corniger, an invasive neotropical termite recently introduced to Florida, with information on the costs to treat and repair affected structures, and use this coupled model to simulate the potential short-term costs of establishment of this structural pest. We construct empirical distributions of control and repair costs, using surveys of the pest control industry and homeowners, and use them to simulate treatment and damage costs through a re-sampling procedure. Our results suggest that the net present value of potential costs from an unchecked N. corniger invasion in Florida range between $6.9 and $9.9 million over the next 10 years. 相似文献
154.
分析了火电厂烟气脱硫变动成本的构成,探讨了影响脱硫变动成本的因素,提出了控制脱硫变动成本和调整脱硫电价的建议。 相似文献
155.
Rural market imperfections and the role of institutions in collective action to improve markets for the poor 总被引:1,自引:1,他引:0
Many countries in sub‐Saharan Africa have liberalized markets to improve efficiency and enhance market linkages for smallholder farmers. The expected positive response by the private sector in areas with limited market infrastructure has however been very limited. The functioning of markets is constrained by high transaction costs and coordination problems along the production‐to‐consumption value chain. New kinds of institutional arrangements are needed to reduce these costs and fill the vacuum left when governments withdrew from markets in the era of structural adjustments. One of these institutional innovations has been the strengthening of producer organizations and formation of collective marketing groups as instruments to remedy pervasive market failures in rural economies. The analysis presented here with a case study from eastern Kenya has shown that marketing groups pay 20–25% higher prices than other buyers to farmers while participation was also positively correlated with adoption of improved dryland legume varieties, crops not targeted by the formal extension system. However the effectiveness of marketing groups is undermined by external shocks and structural constraints that limit the volume of trade and access to capital and information, and require investments in complementary institutions and coordination mechanisms to exploit scale economies. Successful groups have shown high levels of collective action in the form of increased participatory decision making, member contributions and initial start‐up capital. Failure to pay on delivery, resulting from lack of capital credit, is a major constraint that stifles competitiveness of marketing groups relative to other buyers. These findings call for interventions that improve governance and participation; mechanisms for improving access to operating capital; and effective strategies for risk management and enhancing the business skills of farmer marketing groups. 相似文献
156.
Many regions worldwide are experiencing rapid urbanization, and often along with growth in the local economy and population comes worsening air quality. Such regions typically find that addressing the additional challenge of polluted air is difficult. This paper reports the results of an assessment of the present health and related economic costs of poor air quality in the San Joaquin Valley of California. Further, it suggests how such assessments can support strategies to pursue pollution reductions that offer the largest near-term gains, by rigorously modeling the associations between pollution levels, demographic groups, and recognized adverse health effects. 相似文献
157.
Transaction costs and the clean development mechanism 总被引:2,自引:0,他引:2
Bruce P. Chadwick 《Natural resources forum》2006,30(4):256-271
The emissions trading provisions of the Kyoto Protocol and its clean development mechanism (CDM) are designed to permit greenhouse gas (GHG) emission reductions at the lowest cost globally. However, to ensure climate integrity, these reductions must pass through vigilant approval, monitoring and evaluation procedures that create additional transaction costs unrelated to the physical process of eliminating GHGs. Moreover, the CDM's additionality criterion creates constraints that magnify the influence of these transaction costs on project viability. If these costs are extreme, they could undermine the success of the CDM, and possibly of the Kyoto Protocol itself. This article describes the trading provisions of the treaty, creates a working definition of transaction costs, and discusses their effects. It then analyzes the process of creating a CDM project to identify the sources of transaction costs, illustrated by an example of a fuel substitution project in Ghana. The conditions for project profitability are analyzed and compared with recent GHG emission credit prices in Europe. The specific Ghanaian results are not generalizable to all CDM projects, but the model does suggest a template that can be used to analyze the effects of project and transaction costs in other contexts. 相似文献
158.
159.
H. J. Vaux 《Journal of the American Water Resources Association》1977,13(3):469-478
ABSTRACT: Liquid dominated geothermal systems are expected to account for most of the growth in geothermal energy production in the coming decades. Production of water from such systems could significantly augment fresh water supplies. The feasibility of water exploitation is clouded by potential problems related to seismic impacts, land subsidence and the composition of geothermal brines. If these problems can be overcome at little cost, desalination of brines may be feasible. Estimates of water production costs are presented for a variety of desalination technologies, plant sizes and brine water compositions. These estimates show that production costs will range from $139.10/A.F. to $436.00/A.F. at the plant boundary. Economies of scale and brine composition are important determinants of cost. Production costs are substantially in excess of the value of water in alternative uses. However, in certain unique situations, it may be efficient to desalt brines for use in upgrading the quality of municipal water, industrial process water and irrigation water. Unique situations aside, geothermal brines are not likely to provide an economical source of fresh water in the absence of striking changes in the patterns of supply and demand for water. 相似文献
160.
水资源配置大致存在完全政府配置、完全市场配置和准市场配置3种模式。中国正处于水权制度改革的过程中,水资源配置制度有从完全政府配置转向依靠市场配置的趋势。新制度经济学的交易成本理论和租值消散理论可以为新的水权制度的设计和选择提供依据。水资源的不同配置制度对应着相应的交易成本,相对较好的制度应该能在扣除交易成本之后获得较多的社会净租值。目前我国水资源管理的当务之急是根据经济理性,科学地界定好水资源的公有和私有权利,并由完全政府管制向市场体制转型。 相似文献