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791.
Ren Yong 《Journal of Material Cycles and Waste Management》2007,9(2):121-129
This article makes an attempt to answer the three questions of why China is devoting its full effort to promoting a circular
economy, what a circular economy is, and how to implement a circular economy in China. The evolutionary process of a circular
economy in China, from introduction of the concept and the relevant actions of national decision making to demonstration of
the system nationwide, has taken only around 6 years, with strong encouragement from politicians and the urgent need to cope
with environmental pollution and a severe shortage of natural resources. The circular economy in China is now being actively
implemented at three levels: enterprises, eco-industrial parks, and regions. The consolidated theoretical bases of ecology
and economics have helped the circular economy to define its position as a new economic model to effectively resolve the problems
of resources and the environment. In this regard, material flow management is naturally a unique planning and management method
for implementation of a circular economy, and eco-efficiency is a good indicator to measure circular economic activities.
Of particular significance has been initiation of the legislative process for the Circular Economy Law, which is among a number
of initiatives developing core policies for a circular economy in China. Stringent enforcement of a set of policies for energy
saving and pollution abatement nowadays in China will certainly create an enabling environment for the development of a circular
economy. 相似文献
792.
793.
我国部分地方规定了水污染物排放许可证制度,由于此类法律文件法律效力的低层级性,制约着水污染防治的司法与执法实践。提高设定该制度法律文件效力位阶,不仅可以解决调整该制度法制不统一状况,而且为其进行法律规制提供了直接、具体的法律依据。对促使排污主体科学、合理排污将起到积极作用。 相似文献
794.
我院校园木本植物物种多样性调查与分析评价 总被引:1,自引:1,他引:1
对中国环境管理干部学院校园内现有的木本植物进行了种类统计和鉴定,发现校园内大部分木本植物生长良好,但是部分木本植物因人为破坏、气候不适而生长不良甚至死亡。我们应该提高认识、明确方向、优化结构、利用资源、加强养护,对校园植物资源进行管护。 相似文献
795.
796.
Li Fuzhu School of Urban Environmental Science Northeast Normal University Changchun China 《中国人口.资源与环境(英文版)》2005,(4)
1INTRODUCTION Human Capital Theory(HCT)'s idea origin recalls westernclassical political economics in the eighteen century.HCTcame into being in the middle and later periods of the20century,sprang up in the1960s and1970s,was introducedinto China in the1980s and is still one of the hotspotsin economic research.Foreign and domestic scholars havemade a lot of deep researches and important achievements.2FOREIGN RESEARCHIn the1950s,facing many"economic enigma"such as"Solow residual"an… 相似文献
797.
中国火灾最佳灰色回归组合预测模型 总被引:4,自引:6,他引:4
火灾现象具有随机性、模糊性,是个复杂的灰色系统行为。研究火灾发生的规律及发展趋势,具有实用价值。笔者给出最小二乘估计意义下的最佳组合预测模型的定义,并求得其权的公式和证明权的惟一性;用回归分析方法建立多个回归模型,并按3条标准即①回归指数大、②系统误差小、③模型精度高,选定最佳非线性回归模型;用灰色理论建立多个灰色模型,并按3条标准即①后验差比值小、②小误差概率大、③预测关联度大,选定最佳灰色模型;再将最佳回归模型与最佳灰色模型有机地结合起来建立中国火灾最佳灰色回归组合预测模型。组合预测模型综合利用前两者提供的不同的有用信息,改善了单一模型的局限性,提高了预测精度,减少了预测误差。组合模型预测中国年火灾起数处于动态增长过程。 相似文献
798.
湘江流域洪水灾害综合风险评价 总被引:26,自引:4,他引:26
依据灾害系统理论,在综合考虑致灾因子、孕灾环境和承灾体的基础上,从致灾因子、孕灾环境的自然属性和承灾体的社会属性两方面出发,以县级行政单元为基本评价单元,进行了湘江流域洪水灾害的综合风险评价。在综合考虑降雨量、地形以及历史上洪水灾害发生频次等自然因素的条件下,利用地图代数分析得到了湘江流域洪水灾害危险性评价图;在综合考虑人口密度、耕地面积百分比、人均GDP和单位面积水库和塘坝容量等社会经济指标的基础上,利用模糊综合评判法得到了湘江流域洪水灾害脆弱性评价图。在此基础上采取“乘”模型的计算公式,即风险=危险性×脆弱性,将湘江流域洪水灾害风险划分为高风险、较高风险、中等风险、较低风险和低风险5个等级,并借助地理信息系统软件编制了湘江流域洪水灾害综合风险等级评价图。 相似文献
799.
Prevalence of low back pain in three occupational groups in Shanghai, People's Republic of China 总被引:5,自引:0,他引:5
PROBLEM: Low back pain (LBP) is one of the most prevalent work-related conditions affecting employed populations in developed countries, yet little is known about this condition among the world's largest, single-nation labor force: The People's Republic of China. METHOD: This is a cross-sectional study of the prevalence of low back pain (LBP) among garment workers, battery/kiln workers, and teachers in Shanghai, People's Republic of China. Data were collected by personal interview and physical examination at six work sites. The overall response rate was 78%. RESULTS: The overall (N=383) self-reported annual prevalence of LBP symptoms lasting 24 hours or more was 50%. Garment workers had a higher annual prevalence of LBP (74%) than teachers (40%), prevalence ratio (PR=1.9, 95% CI=1.4-2.4). DISCUSSION: The overall annual prevalence of self-reported LBP (50%) was higher than that reported among 50 other Chinese employed study populations (30%). Healthy worker effects may have limited the conclusions from this cross-sectional study. SUMMARY: These results suggest that LBP is a prevalent condition in Chinese workers and that more work should be done to estimate its impact on the Chinese workforce. The findings for garment workers were consistent with increased risk of LBP among persons doing work in fixed, sedentary postures. 相似文献
800.
The idea of pre-impact recovery planning has recently been promoted by researchers and practitioners, but very little research has been done to evaluate its effects on disaster recovery. This study compared two jurisdictions — the city of Los Angeles, California and Taichung county in Taiwan — in their recovery from earthquakes. Although the two cases also differ with respect to variables other than the presence of pre-impact recovery plans, the available data suggest that having a pre-impact recovery plan facilitates housing reconstruction and allows local officials to make more effective use of the window of opportunity after disaster to integrate hazard mitigation into the recovery process. 相似文献