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951.
China’s economic growth has a serious impact on the environment and resources. How much real cost did China pay for its economic growth? This paper estimates the monetary costs of resource depletion, environmental pollution, and ecological degradation. The paper examines the geographic distribution of resource and environmental losses across 31 provinces. The findings allow us to reach the following conclusions. First, the national cost of resource depletion, environmental pollution, and ecological degradation in 2005 was 2.5 trillion RMB. It accounted for 13.5% of China’s gross domestic product (GDP). Secondly, the cost of resource depletion, ecological degradation, and environmental pollution has a different spatial distribution. The cost of resources depletion mainly distributes in the central area, the cost of environmental pollution is in the eastern area, and the cost of ecological degradation lies in the western area. Thirdly, the cost of natural resources depletion is 1,672.5 billion RMB, accounting for 67.8% of the total cost of resource and environment. It indicates that economic development has a high cost of resource depletion.  相似文献   
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随着城市化的进程,垃圾处理设施成为影响城市化质量的重要指标。依据人们实际所关注的垃圾处理设施的总成本和负效应两个因素,在前人研究的基础上,建立了垃圾收运多目标模型,使得总成本和负效应最优化。根据模型设计了粒子群算法,该算法属于智能算法,且精度高,收敛快,在许多领域也得到广泛应用。用设计的粒子群算法并结合案例求出了Pareto最优解,给出三种决策方案,验证了模型和算法的有效性和可行性,为决策者提供了一种理论参考。  相似文献   
954.
简要介绍了行车司机职业适应性测试和评价的基本原理及其重要性。  相似文献   
955.
Consumer demand for environmentally and socially responsible products is the driving force behind the expansion of competing certification systems. Paradoxically, this has led to an increasingly crowded marketplace for labels and confusion among stakeholders such as producers, retailers and buyers, rather than providing clear and reliable product information as intended. The situation has sparked a debate about the future of certification schemes and the need for a more streamlined system. This article explores some of the innovative ideas coming from the current discussion regarding biofuel certification and standardisation and outlines how those ideas can be applied to create a global generic standard-setting scheme for natural resources.  相似文献   
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This paper focuses on the diversity of engine technologies for low emission vehicles (LEVs) that are developed by car manufacturers in order to substitute for the conventional internal combustion engine vehicle (ICEV). Our purpose is to analyse the competition between the various technologies for LEVs as well as the innovative strategy of car manufacturers. We first propose to define and to represent these technological trajectories in order to compare their performances and to identify their strengths and weaknesses. The technological bottlenecks, the barriers to the adoption of these alternative engine technologies as well as the features of this technological competition are underlined. We then use a patent data analysis to study the patent portfolios of the main car manufacturers in these technologies over the period [1990–2005]. The dynamics of patent applications by car manufacturers gives insight on the competition among technologies and on the strategy of firms. This analysis emphasises the progressive diversification of firms' patent portfolios over the whole set of engine technologies and the differentiated strategic positioning of car manufacturers according to countries.  相似文献   
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