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441.
绿色国内生产总值(GDP)核算 总被引:22,自引:1,他引:22
在文献1和2中,我们从实现资源经济一体化核算出发,设计出了资源─经济一体化核算投入产出表,并对有关核算问题(如环保费用测定问题、价格决定问题等)进行了研究,给出了相关的结果。作为后续研究,本文继续以投入产出核算为研究背景,主要对涉及总量核算尤其是“绿色”国内生产总值核算问题进行深入研究。 相似文献
442.
本文根据辐射型生态工程——星火养殖场的生产情况,建立新型投入产出模型,结合线性规划模型,对系统结构进行综合评价和优化设计。模式Ⅰ优化结果,利润最大值41万元,是实际值的4倍;模式Ⅱ的最优结构与模式Ⅰ的相同,利润最大值77万元。结果表明,充分利用系统设施和不断采用新技术是取得最佳效益的两个重要方面。 相似文献
443.
444.
Energy use scenario and resulting rice yield of 576 farms belonging to six agroclimatic zones of Assam, India were investigated. Input energy from eight distinct sources, viz., human, animal, diesel, commercial chemical fertilizer, farm yard manure (FYM), seed, pesticide chemical and machinery were determined on the basis of collected data and using standard procedure. Based on the power sources used and application of commercial chemical fertilizer, four categories of farms were delineated: (i) animal power without commercial fertilizer (APNF), (ii) animal power with commercial fertilizer (APF), (iii) mechanical power without commercial fertilizer (MPNF) and (iv) mechanical power with commercial fertilizer (MPF). The best-fit curve of energy versus yield indicated that use of commercial chemical fertilizer and mechanical power resulted in higher rice yield at higher level of input energy. Moreover, as the use of energy increased the yield increased up to maxima and then declined at higher levels of energy. This was observed in all four categories of farms with variation in yield–energy values. The average values of energy input (MJ ha−1) and corresponding yield (kg ha−1) for the APNF, APF, MPNF and MPF type of farms were (5220, 1980); (9050, 3170); (5100, 2360) and (8320, 3800), respectively. Renewable energy dominated the rice cultivation in Assam contributing more than 50% of the total input energy with the exception of MPF category of farm where share of renewable and non-renewable were found to be almost equal. Among the farm operations, tillage was the highest energy consuming operation followed by threshing, harvesting and transplanting for all four categories of farms. However, it was observed that rice yield was not positively correlated with tillage energy. 相似文献
445.
446.
R. Subramanian Neil M. Donahue Anna Bernardo-Bricker Wolfgang F. Rogge Allen L. Robinson 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):8002-8019
We present estimates of the vehicular contribution to ambient organic carbon (OC) and fine particle mass (PM) in Pittsburgh, PA using the chemical mass balance (CMB) model and a large dataset of ambient molecular marker concentrations. Source profiles for CMB analysis are selected using a method of comparing the ambient ratios of marker species with published profiles for gasoline and diesel vehicle emissions. The ambient wintertime data cluster on a hopanes/EC ratio–ratio plot, and therefore can be explained by a large number of different source profile combinations. In contrast, the widely varying summer ambient ratios can be explained by a more limited number of source profile combinations. We present results for a number of different CMB scenarios, all of which perform well on the different statistical tests used to establish the quality of a CMB solution. The results illustrate how CMB estimates depend critically on the marker-to-OC and marker-to-PM ratios of the source profiles. The vehicular contribution in the winter is bounded between 13% and 20% of the ambient OC (274±56–416±72 ng-C m−3). However, variability in the diesel profiles creates uncertainty in the gasoline–diesel split. On an OC basis, one set of scenarios suggests gasoline dominance, while a second set indicates a more even split. On a PM basis, all solutions indicate a diesel-dominated split. The summer CMB solutions do not present a consistent picture given the seasonal shift and wide variation in the ambient hopanes-to-EC ratios relative to the source profiles. If one set of source profiles is applied to the entire dataset, gasoline vehicles dominate vehicular OC in the winter but diesel dominates in the summer. The seasonal pattern in the ambient hopanes-to-EC ratios may be caused by photochemical decay of hopanes in the summer or by seasonal changes in vehicle emission profiles. 相似文献
447.
This paper explains the application of structural path analysis (SPA), an input–output-based technique for measuring flows in ecological and linked ecological–economic networks. Previous methods of input–output flow analysis have concluded with aggregate indexes relying on the summing feature of the Leontief inverse in order to completely account for throughflows along a multitude of inter-compartmental paths. This paper shows that for most linear dissipative networks, a manageable number of paths of limited length exist that cover in the order of 99% or more of total throughflow. These paths can be conveniently extracted, enumerated and ranked using SPA. 相似文献
448.
449.
地震灾害产业关联间接经济损失评估 总被引:4,自引:0,他引:4
地震灾害破坏了一个城市或地区的经济体系的均衡运行状态,震后“残余”的生产能力资源必须经过一段时间的重新调整,才能达到某一新的、较低程度的均衡水平。本文利用投入产出分析法,从机会成本的观点,对调整阶段的生产能力资源“呆滞”损失即产业关联损失进行了评估。 相似文献
450.
投入产出模型在工业生态系统分析中的应用 总被引:1,自引:0,他引:1
宁淼 《中国人口.资源与环境》2006,16(4):69-72
应用投入产出模型构建出工业生态系统物质流分析的基本框架,在此基础上提出工业生态系统“关键种企业”的识别方法。以及工业生态系统企业能量消耗特征、累计污染排放特征的量化分析方法。这些分析方法将是辅助工业生态系统日常管理与维护的有力工具。 相似文献