The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis ...The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis (SBM-DEA) has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency (OE) of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency (SE) was higher than the pure technological efficiency (PTE); PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped' trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle展开更多
The study on the enterprise's energy efficiency is one of the most important fields of energy efficiency research. Most studies used DEA and aggregate data to estimate the energy efficiency of enterprises. In this st...The study on the enterprise's energy efficiency is one of the most important fields of energy efficiency research. Most studies used DEA and aggregate data to estimate the energy efficiency of enterprises. In this study, based on Cobb-Douglas production function, we make a SFA model which takes the energy input and CO2 emission into account. By using the SFA model, we calculate the refineries' total-factor energy efficiency with Sinopec refineries' micro-data from 2004 to 2009. Meanwhile, we do empirical study on the factors which influence the energy efficiency. In the last, we put forward some advices so as to improve energy efficiency.展开更多
The aim of this paper is the analysis of methodology for selecting the best model for forecasting of fuelwood demand in Greece for the years 2020, 2025 and 2030 with a final objective the decision-making in the sector...The aim of this paper is the analysis of methodology for selecting the best model for forecasting of fuelwood demand in Greece for the years 2020, 2025 and 2030 with a final objective the decision-making in the sector of forest bioenergy. A complete time series of historical data exists that concerns: (a) the consumption of fuelwood and (b) the six most important from the independent variables that could influence the consumption of fuelwood, whose data cover the time period 1989-2010. The evaluation and choice of the best model was realized with the help of the following six statistical criteria: (a) the size of standard error of theoretical values of dependant variable, S. E.; (b) the value of adjusted R square (R2); (c) the non-existence of autocorrelation among the residuals (ei) through the criterion Durbin-Watson; (d) the statistical significance of models coefficients through t criterion; (e) the statistical significance of models through F criterion and (f) the non-existence of multicolinearity through the values of Variance Inflation Factor.展开更多
The world today is .faced with the critical challenge of developing industries .for both high technological efficiency and possibly less impact on resources and the environment. This paper employs the Slacks-based mea...The world today is .faced with the critical challenge of developing industries .for both high technological efficiency and possibly less impact on resources and the environment. This paper employs the Slacks-based measure (SBM) to conduct an empirical analysis of China's industrial environmental efficiency between 1998 and 2008. We.found a slight decline in SBM nationwide due to the combined effects of resource^environmental constraint as well as technological progress. From a static perspective, there is a clear disparity in coordination among regions, particularly between western regions and eastern coastal regions. From a dynamic perspective, there is limited change in the coordination of industries with natural resources and the environment in coastal and central regions, but a marked decline in the northeast and western regions. This contrast can be traced to the .following reasons: the capital-intensive structure of the economy and the high proportion of large industrial enterprises that restrict the improvement of SBM environmental efficiency. Higher living standards, indigenous innovation, acquisition of new technologies, and foreign direct investment will be conducive to industries'synchronous development with natural resources and the environment.展开更多
基金Key Research Program of Chinese Academy of Sciences(No.KZZD-EW-06-03-03)
文摘The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis (SBM-DEA) has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water re- source utilization in China between 2000 and 2012. The overall efficiency (OE) of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency (SE) was higher than the pure technological efficiency (PTE); PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied ac- cording to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted U-shaped' trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban ~ezle
文摘The study on the enterprise's energy efficiency is one of the most important fields of energy efficiency research. Most studies used DEA and aggregate data to estimate the energy efficiency of enterprises. In this study, based on Cobb-Douglas production function, we make a SFA model which takes the energy input and CO2 emission into account. By using the SFA model, we calculate the refineries' total-factor energy efficiency with Sinopec refineries' micro-data from 2004 to 2009. Meanwhile, we do empirical study on the factors which influence the energy efficiency. In the last, we put forward some advices so as to improve energy efficiency.
文摘The aim of this paper is the analysis of methodology for selecting the best model for forecasting of fuelwood demand in Greece for the years 2020, 2025 and 2030 with a final objective the decision-making in the sector of forest bioenergy. A complete time series of historical data exists that concerns: (a) the consumption of fuelwood and (b) the six most important from the independent variables that could influence the consumption of fuelwood, whose data cover the time period 1989-2010. The evaluation and choice of the best model was realized with the help of the following six statistical criteria: (a) the size of standard error of theoretical values of dependant variable, S. E.; (b) the value of adjusted R square (R2); (c) the non-existence of autocorrelation among the residuals (ei) through the criterion Durbin-Watson; (d) the statistical significance of models coefficients through t criterion; (e) the statistical significance of models through F criterion and (f) the non-existence of multicolinearity through the values of Variance Inflation Factor.
文摘The world today is .faced with the critical challenge of developing industries .for both high technological efficiency and possibly less impact on resources and the environment. This paper employs the Slacks-based measure (SBM) to conduct an empirical analysis of China's industrial environmental efficiency between 1998 and 2008. We.found a slight decline in SBM nationwide due to the combined effects of resource^environmental constraint as well as technological progress. From a static perspective, there is a clear disparity in coordination among regions, particularly between western regions and eastern coastal regions. From a dynamic perspective, there is limited change in the coordination of industries with natural resources and the environment in coastal and central regions, but a marked decline in the northeast and western regions. This contrast can be traced to the .following reasons: the capital-intensive structure of the economy and the high proportion of large industrial enterprises that restrict the improvement of SBM environmental efficiency. Higher living standards, indigenous innovation, acquisition of new technologies, and foreign direct investment will be conducive to industries'synchronous development with natural resources and the environment.