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911.
912.
我国区域城乡互动与关联发展综合评价   总被引:19,自引:0,他引:19  
城乡互动与美联发展是协调城乡关系,促进城乡共同发展的有效途径。但我国区域城乡发展水平还存在较大差异,如何正确衡量和反映这种差异是进一步优化不同区域城乡发展的决策依据。综合应用多种评价方法对我国31十省(直辖市)的城乡互动与关联裳展进行综合评价和排序,并采用Kerndalls W协和系数对结果序到作一致性检验,将综合多种方法的结果作为最后评价值,较好地反映了我国区域城乡互动与关联发展的发展水平。  相似文献   
913.
The effects of chemical oxygen demand (COD) concentration in the influent on nitrous oxide (N2O) emissions, together with the relationships between N2O and water quality parameters in free water surface constructed wetlands, were investigated with laboratoryscale systems. N2O emission and purification performance of wastewater were very strongly dependent on COD concentration in the influent, and the total N2O emission in the system with middle COD influent concentration was the least. The relationships between N2O and the chemical and physical water quality variables were studied by using principal component scores in multiple linear regression analysis to predict N2O flux. The multiple linear regression model against principal components indicated that different water parameters affected N2O flux with different COD concentrations in the influent, but nitrate nitrogen affected N2O flux in all systems.  相似文献   
914.
对未达到环境保护验收要求的各类环境保护问题提出整改与补救措施,是实现环保验收目的的基本要求.根据南京地铁验收过程中的工作实际,就已运营的城市轨道交通工程如何提出适宜的噪声、振动验收整改建议提出了看法.  相似文献   
915.
This growth chamber study was designed to determine rates of nitrogen fixation, growth, productivity and concentrations of nitrogen and phosphorus during vegetative growth, flowering and the beginning of the fruiting and ripening period in Pisum sativum plants supplied with different concentrations of nitrate and nodulated by various strains of Rhizobium leguminosarum. Noninoculated control plants were grown under the same nutritional conditions. Nodulated and unnodulated plants responded differently to treatment. The effects of inoculation with Rhizobium and the nitrate treatments on the parameters of growth and nitrogen content varied with plant age. Although the presence of nitrate in the culture medium inhibited nodulation and acetylene reducing activity (ARA), the different Rhizobium strains used in the inoculations led to variations in tolerance to combined nitrogen.  相似文献   
916.
Fisheries management is increasingly transitioning towards collaborative governance. Collaborative systems depend on stakeholders’ capacity to design and implement legitimate and scientifically robust management plans within collective action arenas. Here we propose that collaborative governance outcomes, in fisheries management, will benefit from using structured participatory decision making frameworks that enhance deliberative thinking among stakeholders. We tested our approach in the artisanal fishery of Chile, an important producer of marine resources. Recently in 2013, Chile made important changes to fisheries policies by creating multi-sectorial management committees to manage de facto open access fishing areas. We applied a structured decision making framework to inform the restructuring of a management plan within a committee. As a result, we identified goals,objectives and indicators, including social, economic, biological and ecological dimensions; we explored tradeoffs, assessing the relative importance of the objectives; finally, we created scenarios and prioritized alternatives, reflecting on the interplay between self-regulation and government control. Members of the management committee were able to rationalize the different steps of the framework and identify ways forward which highlighted the importance of self-regulation in comparison to central authorities’ control. We concluded that structured decision making promotes spaces for rational analysis of alternatives costs and benefits. Promoting deliberative thinking in fisheries management can improve equity, legitimacy and sustainability of collaborative governance.  相似文献   
917.
This study examines the links between mineral dependency and corruption. Specifically, it develops a cross-section econometric model that estimates the effects of per capita income, fuel exports, non-fuel exports, and average per unit value of mineral exports on corruption.  相似文献   
918.
文章通过对我国地区10kV及以下配电线路无功补偿的现状,并结合有关数据,对配电线路无功补偿的必要性、补偿位置选择进行了分析。提出提高中、低压配电网功率因数,能够稳定提高线路电路输送能力和供电质量,并且能够大大降低线路损耗,既具有明显的社会和经济效益,也具有现实意义。  相似文献   
919.
A number of models have been proposed to calculate overpressure and impulse from accidental industrial explosions. When the blast is produced by explosives, pyrotechnics or unstable substances, the TNT equivalent model is widely used. From the curves given by this model, data are fitted to obtain equations showing the relationship between overpressure, impulse and distance. These equations, referred to here as characteristic curves, can be fitted by means of power equations, which depend on the TNT equivalent mass. Characteristic curves allow determination of overpressure and impulse at each distance.  相似文献   
920.
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   
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