This paper examined the impacts of the total energy consumption control policy and energy quota allocation plans on China′s regional economy. This research analyzed the influences of different energy quota allocation...This paper examined the impacts of the total energy consumption control policy and energy quota allocation plans on China′s regional economy. This research analyzed the influences of different energy quota allocation plans with various weights of equity and efficiency, using a dynamic computable general equilibrium(CGE) model for 30 province-level administrative regions. The results show that the efficiency-first allocation plan costs the least but widens regional income gap, whereas the outcomes of equity-first allocation plan and intensity target-based allocation plan are similar and are both opposite to the efficiency-first allocation plan′ outcome. The plan featuring a balance between efficiency and equity is more feasible, which can bring regional economic losses evenly and prevent massive interregional migration of energy-related industries. Furthermore, the effects of possible induced energy technology improvements in different energy quota allocation plans were studied. Induced energy technology improvements can add more feasibility to all allocation plans under the total energy consumption control policy. In the long term, if the policy of the total energy consumption control continues and more market-based tools are implemented to allocate energy quotas, the positive consequences of induced energy technology improvements will become much more obvious.展开更多
With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive o...With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive operations,a reasonable air defense weapon assignment strategy is a key step.In this paper,a multi-objective and multi-constraints weapon target assignment(WTA)model is established that aims to minimize the defensive resource loss,minimize total weapon consumption,and minimize the target residual effectiveness.An optimization framework of air defense weapon mission scheduling based on the multiobjective artificial bee colony(MOABC)algorithm is proposed.The solution for point-to-point saturated attack targets at different operational scales is achieved by encoding the nectar with real numbers.Simulations are performed for an imagined air defense scenario,where air defense weapons are saturated.The non-dominated solution sets are obtained by the MOABC algorithm to meet the operational demand.In the case where there are more weapons than targets,more diverse assignment schemes can be selected.According to the inverse generation distance(IGD)index,the convergence and diversity for the solutions of the non-dominated sorting genetic algorithm III(NSGA-III)algorithm and the MOABC algorithm are compared and analyzed.The results prove that the MOABC algorithm has better convergence and the solutions are more evenly distributed among the solution space.展开更多
The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been pe...The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been performed for the ORC system using nanorefrigerant,the material and energy input,characteristic indicators and comprehensive index of environmental impact,total energy consumption and energy payback time(BPBT)of the whole life cycle of ORC system using Al_(2)O_(3)/R141b nanorefrigerant were calculated.Total environmental comprehensive indexes reveal that ECER-135 index decrease by 1.5%after adding 0.2%Al_(2)O_(3)nanoparticles to R141b.Based on the contribution analysis and sensitivity analysis,it can be found out ORC system manufacturing is of the most critical stage,where,the ECER-135 index of ORC component production is the greatest,followed by the preparation process of R141b,transportation phase,and that of Al_(2)O_(3)nanoparticles preparation is small.The retirement phase which has good environmental benefits affects the result significantly by recycling important materials.Meanwhile,the main cause and relevant suggestion for improvement were traced respectively.Finally,the environmental impacts of various power generations were compared,and results show that the power route is of obvious advantage.Among the renewable energy,ORC system using Al_(2)O_(3)/R141b nanorefrigerant with minimal environmental impact is only 0.67%of coal-fired power generation.The environmental impact of current work is about 14.34%of other nations’PV results.展开更多
The total electricity consumption(TEC)can accurately reflect the operation of the national economy,and the forecasting of the TEC can help predict the economic development trend,as well as provide insights for the for...The total electricity consumption(TEC)can accurately reflect the operation of the national economy,and the forecasting of the TEC can help predict the economic development trend,as well as provide insights for the formulation of macro policies.Nowadays,high-frequency and massive multi-source data provide a new way to predict the TEC.In this paper,a"seasonal-cumulative temperature index"is constructed based on high-frequency temperature data,and a mixed-frequency prediction model based on multi-source big data(Mixed Data Sampling with Monthly Temperature and Daily Temperature index,MIDAS-MT-DT)is proposed.Experimental results show that the MIDAS-MT-DT model achieves higher prediction accuracy,and the"seasonal-cumulative temperature index"can improve prediction accuracy.展开更多
Pakistan has been suffering from a chronic deficit in the current account for many decades. Current account deficit strengthens the foreign currency against the home currency which makes imports of good and services m...Pakistan has been suffering from a chronic deficit in the current account for many decades. Current account deficit strengthens the foreign currency against the home currency which makes imports of good and services more expensive as compared to exports and causes devaluation of home currency. The main objective of this paper is to find out how the current account deficit is influenced by different economic factors. Our regression model’s estimated results indicate that the percentage change in the volume of imports, foreign direct investments and total consumption are positively correlated and, on the other hand, exports, workers remittance, growth in agriculture and manufacturing are negatively correlated with the current account balance of Pakistan during the observed period 1972-2001.展开更多
Straw returning into field is a direct and effective measure to reduce the straw burning and improve the soil organic matter content.Straw returning directly to field needs higher performance machines,especially under...Straw returning into field is a direct and effective measure to reduce the straw burning and improve the soil organic matter content.Straw returning directly to field needs higher performance machines,especially under the condition of large amount of straw in the field is more difficult.Therefore,the model of conservation tillage by combination of subsoiling and straw returning was studied.Experiments on combined tillage machine for effect of subsoiling on working quality and total power consumption for high stubble straw returning were carried out.The high stubble rape field was used as the test field;forward speed and PTO speed of tractor were taken as the test factors.Straw coverage rate and straw proportion of the lower half burying layer were taken as the test indexes of the working quality.Subsoiling and rotary burying(SRB)returning operation was used as experimental group and direct rotary burying(DRB)returning operation was the control group.The results showed that under different working conditions,the mean value of straw coverage rate of SRB was 93.0%,straw proportion of the lower half burying layer was 52.8%,these values were better than DRB.The straw proportion of the lower half burying layer of SRB compared with DRB increased by 10.5%.Two factors all had a significant effect on it under the SRB and DRB conditions.Subsoiling could significantly reduce the PTO torque.Under low speed,the total power consumption of SRB was slightly smaller,while under high speed,the total power consumption of DRB was slightly smaller.Under the SRB and DRB conditions,two factors both had a significant effect on total power consumption.The optimal working combination(working quality as the primary index)was 1.5 km/h of forward speed and 720 r/min of PTO speed.Under this condition,the straw coverage rate was 94.1%,the straw proportion of the lower half burying layer was 59.0%,and the total power consumption was 35.62 kW.The research confirmed that subsoiling is beneficial to the working quality and total power consumption of high stubble straw returning machine.It could meet the working requirements,and provide a reference for optimizing straw returning machine and improving working quality.展开更多
In order to assess the potential health risks of Hg pollution, total mercury(T–Hg) and methyl mercury(Me Hg) concentrations were determined in air, dust, surface soil, crops, poultry,fish and human hair samples f...In order to assess the potential health risks of Hg pollution, total mercury(T–Hg) and methyl mercury(Me Hg) concentrations were determined in air, dust, surface soil, crops, poultry,fish and human hair samples from an electronic waste(e-waste) recycling area in Taizhou,China. High concentrations of T–Hg and Me Hg were found in these multiple matrices, and the mean concentration was 30.7 ng/m3 of T–Hg for atmosphere samples, 3.1 μg/g of T–Hg for soil, 37.6 μg/g of T–Hg for dust, 20.3 ng/g of Me Hg for rice and 178.1 ng/g of Me Hg for fish,suggesting that the e-waste recycling facility was a significant source of Hg. The inorganic Hg(I–Hg) levels(0.84 μg/g) in hair samples of e-waste workers were much higher than that in the reference samples. Pearson's correlation coefficients showed that strong positive correlations(p 〈 0.01) between hair I–Hg and time staying in industrial area(r = 0.81) and between Me Hg and fish consumption frequency(r = 0.91), imply that workers were mainly exposed to Hg vapor through long-time inhalation of contaminated air and dust, while other population mainly exposed to Me Hg through high-frequency fish consumption. The estimated daily intakes of Hg showed that dietary intake was the major Hg exposure source,and Hg intakes from rice and fish were significantly higher than from any other foods. The estimated total daily intakes(TDIs) of Me Hg for both children(696.8 ng/(kg·day)) and adults(381.3 ng/(kg·day)) greatly exceeded the dietary reference dose(Rf D) of 230 ng/(kg·day),implying greater health risk for humans from Hg exposures around e-waste recycling facilities.展开更多
It is necessary for the sintering process to carry out cleaner production, which is also of great significance to the iron and steel enterprises of a long-flow process. According to the cleaner production standard rec...It is necessary for the sintering process to carry out cleaner production, which is also of great significance to the iron and steel enterprises of a long-flow process. According to the cleaner production standard recently issued by China' s Ministry of Environmental Protection, the research detailed in this study has analyzed and estimated the level of cleaner production at Baosteel in the aspects of technical equipment, resource and energy utilization, product quality, emissions, recycling and environmental management, etc. The research also expatiated some effective measures with which cleaner production can be carried out in Baosteel's sintering process, and discovered some potential opportunities of cleaner production.展开更多
基金National Natural Science Foundation of China(No.41101556,71173212,71203215)
文摘This paper examined the impacts of the total energy consumption control policy and energy quota allocation plans on China′s regional economy. This research analyzed the influences of different energy quota allocation plans with various weights of equity and efficiency, using a dynamic computable general equilibrium(CGE) model for 30 province-level administrative regions. The results show that the efficiency-first allocation plan costs the least but widens regional income gap, whereas the outcomes of equity-first allocation plan and intensity target-based allocation plan are similar and are both opposite to the efficiency-first allocation plan′ outcome. The plan featuring a balance between efficiency and equity is more feasible, which can bring regional economic losses evenly and prevent massive interregional migration of energy-related industries. Furthermore, the effects of possible induced energy technology improvements in different energy quota allocation plans were studied. Induced energy technology improvements can add more feasibility to all allocation plans under the total energy consumption control policy. In the long term, if the policy of the total energy consumption control continues and more market-based tools are implemented to allocate energy quotas, the positive consequences of induced energy technology improvements will become much more obvious.
基金supported by the National Natural Science Foundation of China(71771216).
文摘With the advancement of combat equipment technology and combat concepts,new requirements have been put forward for air defense operations during a group target attack.To achieve high-efficiency and lowloss defensive operations,a reasonable air defense weapon assignment strategy is a key step.In this paper,a multi-objective and multi-constraints weapon target assignment(WTA)model is established that aims to minimize the defensive resource loss,minimize total weapon consumption,and minimize the target residual effectiveness.An optimization framework of air defense weapon mission scheduling based on the multiobjective artificial bee colony(MOABC)algorithm is proposed.The solution for point-to-point saturated attack targets at different operational scales is achieved by encoding the nectar with real numbers.Simulations are performed for an imagined air defense scenario,where air defense weapons are saturated.The non-dominated solution sets are obtained by the MOABC algorithm to meet the operational demand.In the case where there are more weapons than targets,more diverse assignment schemes can be selected.According to the inverse generation distance(IGD)index,the convergence and diversity for the solutions of the non-dominated sorting genetic algorithm III(NSGA-III)algorithm and the MOABC algorithm are compared and analyzed.The results prove that the MOABC algorithm has better convergence and the solutions are more evenly distributed among the solution space.
基金Fund Project in 2020,China(No.KKZ3202052058)and the support of Scientific Research Fund from Yunnan Education Department in China(No.2022J0064).
文摘The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been performed for the ORC system using nanorefrigerant,the material and energy input,characteristic indicators and comprehensive index of environmental impact,total energy consumption and energy payback time(BPBT)of the whole life cycle of ORC system using Al_(2)O_(3)/R141b nanorefrigerant were calculated.Total environmental comprehensive indexes reveal that ECER-135 index decrease by 1.5%after adding 0.2%Al_(2)O_(3)nanoparticles to R141b.Based on the contribution analysis and sensitivity analysis,it can be found out ORC system manufacturing is of the most critical stage,where,the ECER-135 index of ORC component production is the greatest,followed by the preparation process of R141b,transportation phase,and that of Al_(2)O_(3)nanoparticles preparation is small.The retirement phase which has good environmental benefits affects the result significantly by recycling important materials.Meanwhile,the main cause and relevant suggestion for improvement were traced respectively.Finally,the environmental impacts of various power generations were compared,and results show that the power route is of obvious advantage.Among the renewable energy,ORC system using Al_(2)O_(3)/R141b nanorefrigerant with minimal environmental impact is only 0.67%of coal-fired power generation.The environmental impact of current work is about 14.34%of other nations’PV results.
基金supported by the science and technology project of State Grid Corporation of China(Project Code:1400-202157207A-0-0-00)the National Natural Science Foundation of China[grant numbers 72273137].
文摘The total electricity consumption(TEC)can accurately reflect the operation of the national economy,and the forecasting of the TEC can help predict the economic development trend,as well as provide insights for the formulation of macro policies.Nowadays,high-frequency and massive multi-source data provide a new way to predict the TEC.In this paper,a"seasonal-cumulative temperature index"is constructed based on high-frequency temperature data,and a mixed-frequency prediction model based on multi-source big data(Mixed Data Sampling with Monthly Temperature and Daily Temperature index,MIDAS-MT-DT)is proposed.Experimental results show that the MIDAS-MT-DT model achieves higher prediction accuracy,and the"seasonal-cumulative temperature index"can improve prediction accuracy.
基金Sponsored by the National Center of Technology, Policy and Management, Harbin Institute of Technology.
文摘Pakistan has been suffering from a chronic deficit in the current account for many decades. Current account deficit strengthens the foreign currency against the home currency which makes imports of good and services more expensive as compared to exports and causes devaluation of home currency. The main objective of this paper is to find out how the current account deficit is influenced by different economic factors. Our regression model’s estimated results indicate that the percentage change in the volume of imports, foreign direct investments and total consumption are positively correlated and, on the other hand, exports, workers remittance, growth in agriculture and manufacturing are negatively correlated with the current account balance of Pakistan during the observed period 1972-2001.
基金The authors acknowledge that this work was supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201503136)the National Key Technology R&D Program(No.2017YFD0301300).
文摘Straw returning into field is a direct and effective measure to reduce the straw burning and improve the soil organic matter content.Straw returning directly to field needs higher performance machines,especially under the condition of large amount of straw in the field is more difficult.Therefore,the model of conservation tillage by combination of subsoiling and straw returning was studied.Experiments on combined tillage machine for effect of subsoiling on working quality and total power consumption for high stubble straw returning were carried out.The high stubble rape field was used as the test field;forward speed and PTO speed of tractor were taken as the test factors.Straw coverage rate and straw proportion of the lower half burying layer were taken as the test indexes of the working quality.Subsoiling and rotary burying(SRB)returning operation was used as experimental group and direct rotary burying(DRB)returning operation was the control group.The results showed that under different working conditions,the mean value of straw coverage rate of SRB was 93.0%,straw proportion of the lower half burying layer was 52.8%,these values were better than DRB.The straw proportion of the lower half burying layer of SRB compared with DRB increased by 10.5%.Two factors all had a significant effect on it under the SRB and DRB conditions.Subsoiling could significantly reduce the PTO torque.Under low speed,the total power consumption of SRB was slightly smaller,while under high speed,the total power consumption of DRB was slightly smaller.Under the SRB and DRB conditions,two factors both had a significant effect on total power consumption.The optimal working combination(working quality as the primary index)was 1.5 km/h of forward speed and 720 r/min of PTO speed.Under this condition,the straw coverage rate was 94.1%,the straw proportion of the lower half burying layer was 59.0%,and the total power consumption was 35.62 kW.The research confirmed that subsoiling is beneficial to the working quality and total power consumption of high stubble straw returning machine.It could meet the working requirements,and provide a reference for optimizing straw returning machine and improving working quality.
基金financially supported by the National Natural Science Foundation of China (No.21177087)Chinese Ministry of Science and Technology 973 Project (2013CB430005)
文摘In order to assess the potential health risks of Hg pollution, total mercury(T–Hg) and methyl mercury(Me Hg) concentrations were determined in air, dust, surface soil, crops, poultry,fish and human hair samples from an electronic waste(e-waste) recycling area in Taizhou,China. High concentrations of T–Hg and Me Hg were found in these multiple matrices, and the mean concentration was 30.7 ng/m3 of T–Hg for atmosphere samples, 3.1 μg/g of T–Hg for soil, 37.6 μg/g of T–Hg for dust, 20.3 ng/g of Me Hg for rice and 178.1 ng/g of Me Hg for fish,suggesting that the e-waste recycling facility was a significant source of Hg. The inorganic Hg(I–Hg) levels(0.84 μg/g) in hair samples of e-waste workers were much higher than that in the reference samples. Pearson's correlation coefficients showed that strong positive correlations(p 〈 0.01) between hair I–Hg and time staying in industrial area(r = 0.81) and between Me Hg and fish consumption frequency(r = 0.91), imply that workers were mainly exposed to Hg vapor through long-time inhalation of contaminated air and dust, while other population mainly exposed to Me Hg through high-frequency fish consumption. The estimated daily intakes of Hg showed that dietary intake was the major Hg exposure source,and Hg intakes from rice and fish were significantly higher than from any other foods. The estimated total daily intakes(TDIs) of Me Hg for both children(696.8 ng/(kg·day)) and adults(381.3 ng/(kg·day)) greatly exceeded the dietary reference dose(Rf D) of 230 ng/(kg·day),implying greater health risk for humans from Hg exposures around e-waste recycling facilities.
文摘It is necessary for the sintering process to carry out cleaner production, which is also of great significance to the iron and steel enterprises of a long-flow process. According to the cleaner production standard recently issued by China' s Ministry of Environmental Protection, the research detailed in this study has analyzed and estimated the level of cleaner production at Baosteel in the aspects of technical equipment, resource and energy utilization, product quality, emissions, recycling and environmental management, etc. The research also expatiated some effective measures with which cleaner production can be carried out in Baosteel's sintering process, and discovered some potential opportunities of cleaner production.