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51.
Regional development is the trend for future urbanization, and the urban circle is a highly efficient economic spatial pattern of regional development. This study selects statistical data of urban area population, GDP, and the output value of tertiary industry for seven cities in China – Jinan, Zibo, Tai’an, Laiwu, Dezhou, Liaocheng, and Binzhou – in the Shandong provincial capital urban circle from 2005 to 2009. It uses the principles and Zipf model, rank-size rule, and Lotka logarithmic model to analyze and study the hierarchical structure of the metropolitan system and economic development of the Shandong provincial capital urban circle. Based on the above research, this paper provides references for decision-making on enhancement of the metropolitan system structure, improvement in core city primacy index, the optimal adjustment of industrial structure and the optimal allocation of essential resources. 相似文献
52.
本文简要论述了VFP编程语言在TSP浓度计算中的具体应用,内容包括计算程序的主体内容、含义以及程序当中的难点及亮点。 相似文献
53.
长江三角洲区域经济发展的新趋向 总被引:1,自引:0,他引:1
石忆邵 《长江流域资源与环境》2004,13(4):301-304
论述了长江三角洲区域经济发展的四大新趋向,即①从行政区经济到都市圈经济。行政区经济与都市圈经济在运行环境、运行机制、运行目标、运行方式、调控手段等方面存在显著差别,都市圈经济发展模式更适应区域经济一体化发展需要;②从隔江单侧发展到跨江双侧协同发展。如上海、苏南和杭州,都在大力推进跨江发展战略;③从外向型经济或民营经济到两者融合的区域特色经济。经济国际化和民营化相互结合、外地资本和本地资本相互渗透已成为该区域经济发展的重要特色;④从权力型政府到服务型政府。如上海的“服务高地”、苏南的理性执政、浙江的“无为而治”等。 相似文献
54.
While coal seam is being mined, an annular fissure circle with gas accumulation will be formed in the fissure zone as a result of desorption, dissipation and permeation of gas in the goaf area and overlying strata due to fissures from rock caving and mitigation in the roof. The methods for computation of spatial locations of the fissure circle are researched in this paper. Based on these methods, gas drainage technique for the fissure zone is optimized. By applying drill hole returning water method of variables, the height of caving zone that most affects the drainage effects of inclined high dip drill hole was measured on the site. Due to the consistency of the expected height with the computed height of caving lines at different positions, the correctness of the theoretical computation method is further validated. Meanwhile, the parameters of the inclined high dip drill hole at #3311 working face of Hexi Coal Mine are determined by a case study. 相似文献
55.
Sylvie Pouteau 《Journal of Agricultural and Environmental Ethics》2002,15(3):289-303
Substantial equivalence (SE) has beenintroduced to assess novel foods, includinggenetically modified (GM) food, by means ofcomparison with traditional food. Besides anumber of objections concerning its scientificvalidity for risk assessment, the maindifficulty with SE is that it implies that foodcan be qualified on a purely substantial basis.SE embodies the assumption that only reductivescientific arguments are legitimate fordecision-making in public policy due to theemphasis on legal issues. However, the surge ofthe food debate clearly shows that thistechnocratic model is not accepted anymore.Food is more than physico-chemical substanceand encompasses values such as quality andethics. These values are legitimate in theirown right and require that new democraticprocesses are set up for transverse,transdisciplinary assessment in partnershipwith society. The notion of equivalence canprovide a reference scale in which to examinethe various legitimate factors involved:substance (SE), quality (QualitativeEquivalence: QE), and ethics (EthicalEquivalence: EE). QE requires that newqualitative methods of evaluation that are notbased on reductive principles are developed. EEcan provide a basis for the development of anEthical Assurance as a counterpart of QualityAssurance in the food sector. In France, asecond circle of expertise is being set up toaddress the social issues in food public policybeside classical risk assessment by the firstcircle of expertise. Since ethics is likely tobecome an organizing principle of the secondcircle, the equivalence ethical framework canprove instrumental in this context. 相似文献
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57.
土地利用/覆被变化(LUCC)环境效应研究综述 总被引:9,自引:0,他引:9
土地利用/覆被变化能直接反映当今全球环境变化的主导因子--人类活动,为此土地利用/覆被变化产生的环境问题已引起人类社会的广泛关注,深入研究这些问题具有重要的理论意义和实践价值.针对土地利用/覆被变化引起的环境效应的复杂性、累积性,本文在总结国内外LUCC环境效应的研究成果的同时,把LUCC环境效应分为:土壤环境效应、大气环境效应、水环境效应以及生态效应四类进行阐述,并结合目前研究在内容和方法方面存在缺乏统一的指标体系、研究区域时空尺度单一、以单要素静态研究为主、实验研究相对薄弱以及动态模拟不够等问题对其发展趋势进行了探讨. 相似文献
58.
依据赣江流域的系统特征,选择工业开发模式,是地域经济发展的战略核心问题。推进资源有效利用与高度利用,优势产品开发与替代产品开发,实现经济发展趋于由下游而上游的资源型—加工型—技术型产业结构指向的有序转化,资源开发与国土冶理趋于由上游而下游的生态经济良性循环,为赣江流域工业开发模式的基本要点。 相似文献
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60.
采用2008~2011年湖南省及洞庭湖生态经济区五大生产性服务业年末就业人数以及第三产业生产总值为基础数据,运用现状比较、地区产业相似度、相关系数等方法对洞庭湖地区生产性服务业的发展潜力、产业结构的差异程度及与GDP增长的相关性进行研究分析,发现洞庭湖城市群的生产性服务业已初步形成以岳阳为交通运输、仓储和邮政业、金融保险业中心、益阳为租赁和商务服务业中心,常德为生产性服务业补充的基本格局等特点,并针对对其集聚程度不高、新兴产业竞争力不够等特点提出完善集聚、建立产业链、推动创新加快转型等优化对策. 相似文献