Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy effic...Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy efficiency and the influence of lower carbon development.Since work exchange network is a significant part of energy recovery system,its optima design will have dramatically significant effect on energy consumption reduction in chemical process system.With an extension of the developed transshipment model in isothermal process,a novel step-wise methodology for synthesis of direct work exchange network(WEN)in adiabatic process involving heat integration is first proposed in this paper,where a nonlinear programming(NLP)model is formulated by regarding the minimum utility consumption as objective function and optimizing the initial WEN in accordance with the presented matching rules to get the optimized WEN configuration at first.Furthermore,we focus on the work exchange network synthesis with heat integration to attain the minimal total annual cost(TAC)with the introduction of heat-exchange equipment that is achieved by the following strategies in sequence:introducing heat-exchange equipment directly,adjusting the work quantity of the adjacent utility compressors or expanders,and approximating upper/lower pressure limits consequently to obtain considerable cost savings of expanders or compressors and work utility.Finally,a case taken from the literature is studied to illustrate the feasibility and effectiveness of the proposed method.展开更多
Based on extensive micro data sets, this paper examines the relationship among large-scale entry and exit, competition and total factor productivity (TFP) growth of China's industry during economic transition and m...Based on extensive micro data sets, this paper examines the relationship among large-scale entry and exit, competition and total factor productivity (TFP) growth of China's industry during economic transition and market opening. We have arrived at these findings: market opening spurs entry and exit of large numbers of non-state-owned enterprises (non-SOEs) and facilitates dynamic competition; through the stimulation effect of competition, entry and exit push TFP growth on the part of enterprises; through the resource reallocation effect, entry and exit promote growth of the aggregate TFP. However, results indicate that the resource allocation efficiency remains very low in capital-intensive industries where the government intervenes a lot. To conclude, promoting open competition is significant to the growth of industrial sectors 'productivity.展开更多
基金Supported by the National Natural Science Foundation of China(21576036,21406026)
文摘Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy efficiency and the influence of lower carbon development.Since work exchange network is a significant part of energy recovery system,its optima design will have dramatically significant effect on energy consumption reduction in chemical process system.With an extension of the developed transshipment model in isothermal process,a novel step-wise methodology for synthesis of direct work exchange network(WEN)in adiabatic process involving heat integration is first proposed in this paper,where a nonlinear programming(NLP)model is formulated by regarding the minimum utility consumption as objective function and optimizing the initial WEN in accordance with the presented matching rules to get the optimized WEN configuration at first.Furthermore,we focus on the work exchange network synthesis with heat integration to attain the minimal total annual cost(TAC)with the introduction of heat-exchange equipment that is achieved by the following strategies in sequence:introducing heat-exchange equipment directly,adjusting the work quantity of the adjacent utility compressors or expanders,and approximating upper/lower pressure limits consequently to obtain considerable cost savings of expanders or compressors and work utility.Finally,a case taken from the literature is studied to illustrate the feasibility and effectiveness of the proposed method.
文摘Based on extensive micro data sets, this paper examines the relationship among large-scale entry and exit, competition and total factor productivity (TFP) growth of China's industry during economic transition and market opening. We have arrived at these findings: market opening spurs entry and exit of large numbers of non-state-owned enterprises (non-SOEs) and facilitates dynamic competition; through the stimulation effect of competition, entry and exit push TFP growth on the part of enterprises; through the resource reallocation effect, entry and exit promote growth of the aggregate TFP. However, results indicate that the resource allocation efficiency remains very low in capital-intensive industries where the government intervenes a lot. To conclude, promoting open competition is significant to the growth of industrial sectors 'productivity.