Considering that copper mine tailings(CMTs)are commonly mixed with ordinary Portland cement,fly ash(FA),and kaolin to produce geopolymers,to make full use of CMTs,the properties of geopolymers manufactured under diffe...Considering that copper mine tailings(CMTs)are commonly mixed with ordinary Portland cement,fly ash(FA),and kaolin to produce geopolymers,to make full use of CMTs,the properties of geopolymers manufactured under different material mass ratios and curing methods(standard curing,water bath curing,and 60℃curing)are evaluated with significantly increased dosage of CMTs.Porosity and unconfined compressive strength tests,X-ray diffraction,field emission scanning electron microscopy,and energy dispersive spectroscopy are used to determine the physical and mechanical properties,microstructure,and mineral composition of geopolymers.Finally,costs and CO 2 emissions of specimens with different material mass ratios during the preparation processes are compared.The results show that during the geopolymerization of low-calcium materials,various geopolymer gels,including calcium silicate,calcium silicoaluminate,and mainly sodium silicoaluminate gels,coexist.The solid waste,cost,and carbon dioxide emission reductions can reach 100%,166.3 yuan/t,and 73.3 kg/t,respectively.Under a curing condition of 60℃,the sample with a CMTs mass fraction of 70%and an FA mass fraction of 30%meets the requirements of porosity,compressive strength.The resource utilization of CMT and FA is realized in a more economical way.展开更多
The in-situ instrumentation technique for measuring mercury and itsspeciation downstream a utility 100 MW pulverized coal (PC) fired boiler system was developed andconducted by the use of the Ontario hydro method (OHM...The in-situ instrumentation technique for measuring mercury and itsspeciation downstream a utility 100 MW pulverized coal (PC) fired boiler system was developed andconducted by the use of the Ontario hydro method (OHM) consistent with American standard test methodtogether with the semi-continuous emissions monitoring (SCEM) system as well as a mobile laboratoryfor mercury monitoring. The mercury and its speciation concentrations including participate mercuryat three locations of before air preheater, before electrostatic precipitator (ESP) and after ESPwere measured using the OHM and SCEM methods under normal operation conditions of the boiler systemas a result of firing a bituminous coal. The vapor-phase total mercury Hg(VT) concentration declinedwith the decrease of flue gas temperature because of mercury species transformation from oxidizedmercury to particulate mercury as the flue gas moved downstream from the air preheater to the ESPand after the ESP. A good agreement for Hg°, Hg^(2+) and Hg( VT) was obtained between the twomethods in the ash-free area. But in the dense particle-laden flue gas area, there appeared to be abig bias for mercury speciation owing to dust cake formed in the filter of OHM sampling probe. Theparticulateaffinity to the flue gas mercury and the impacts of sampling condition to accuracy ofmeasure were discussed.展开更多
Traditional coal mine safety prediction methods are off-line and do not have dynamic prediction functions.The Support Vector Machine(SVM) is a new machine learning algorithm that has excellent properties.The least squ...Traditional coal mine safety prediction methods are off-line and do not have dynamic prediction functions.The Support Vector Machine(SVM) is a new machine learning algorithm that has excellent properties.The least squares support vector machine(LS-SVM) algorithm is an improved algorithm of SVM.But the common LS-SVM algorithm,used directly in safety predictions,has some problems.We have first studied gas prediction problems and the basic theory of LS-SVM.Given these problems,we have investigated the affect of the time factor about safety prediction and present an on-line prediction algorithm,based on LS-SVM.Finally,given our observed data,we used the on-line algorithm to predict gas emissions and used other related algorithm to compare its performance.The simulation results have verified the validity of the new algorithm.展开更多
International and national concern about detrimental climate change has generated pressure for the shipping industry to play its' role in reducing the 3.3% of global carbon emission it emits. On the 1st January, 2013...International and national concern about detrimental climate change has generated pressure for the shipping industry to play its' role in reducing the 3.3% of global carbon emission it emits. On the 1st January, 2013, the IMO (International Maritime Organisation) enforced regulations to support the reduction of shipping carbon emissions by improving energy efficiency. These measures directly and indirectly affect the daily operations of seafarers and onshore performance and managerial personnel. Whilst the industry has made efforts to raise the awareness of many stakeholders and research has been undertaken to investigate energy efficiency barriers, little has been done to capture the opinions, needs and knowledge of seafarers. A questionnaire was distributed in the last quarter of 2011 to investigate seafarers' awareness, knowledge and motivation towards carbon emissions in general and towards shipping carbon emissions. It also investigated opinions as to which personnel have the most influence over carbon reductions and what are the most important operational improvements that can be made. The authors have collected 317 questionnaire responses. The primary benefit of this study is to support the identification of an operational strategy to improve energy efficiency, including the development of LC-EE (low carbon-energy efficiency) MET (maritime education and training), which is shown to be needed.展开更多
To create evaluation methods in reclamation area according to specific conditions in coal mines, introduced the re- search trends both at home and abroad on plants' carbon fixation and oxygen release, offered, at the...To create evaluation methods in reclamation area according to specific conditions in coal mines, introduced the re- search trends both at home and abroad on plants' carbon fixation and oxygen release, offered, at the same time, several method models on carbon fixation and oxygen release by plants, and gave some suggestions in this field on the basis of reading the ex- periences of former experts. Finally, used biomass method and instrument measurement method to analyze carbon emission benefits in the study area.展开更多
All human activities, including food production, are potentially sources of greenhouse gases (GHG) emissions. In order to provide a better understanding of how to mitigate the GHG emissions, an inventory based on di...All human activities, including food production, are potentially sources of greenhouse gases (GHG) emissions. In order to provide a better understanding of how to mitigate the GHG emissions, an inventory based on different beef supply chains in the United Kingdom and in Brazil was carried out. The carbon footprint of the beef systems was calculated based on the life cycle assessment methodology. Total emissions per kg of bone-free meat were calculated at being 33.85, 33.99 and 45.17 kg of CO2e-100/kg for UK1, UK2 and Brazil farm units, respectively. Based on an average potential for carbon sequestration rate at the proportion of 12:44 for C:CO2 conversion for well managed grasslands, there is a potential sequestration of 1,980 kg of CO2/ha/year. This would potentially reduce the total emissions value for the three distinct supply chains the cases ofUKb UK2 and Brazil, respectively. as being 29.4, 28.4 and 25.4 kg C02-e 100/kg of bone-free meat for展开更多
The volume emission rate (VER) of airglow can be used to investigate atmospheric processes. Satellite-based limb measurement of atmosphere is able to obtain the VER profile of airglow with high vertical resolution. Ho...The volume emission rate (VER) of airglow can be used to investigate atmospheric processes. Satellite-based limb measurement of atmosphere is able to obtain the VER profile of airglow with high vertical resolution. However, the traditional one-dimensional retrieval techniques for VER inversion fail to retrieve horizontal structure of VER profile. Thus, the tomographic technique based on the maximum probability is applied to retrieving two-dimensional VER profile of airglow from infrared limb measurement. This technique could process the observed data with low signal-to-noise ratio caused by the observation angle of less than 180° due to the solid nature of the Earth. For saving the processing time and improving the computing speed of VER inversion, serial tables for storing the large sparse matrix for radiance simulation and a large dataset during iterative estimate of VER are presented. The index and weighting factor of line of sight (LOS) through each grid are saved in initial estimate to avoid being computed repeatedly. Furthermore, the product of observed radiance and corresponding weighting factor obtained in initial iteration is stored as weighted observed radiance for the iterative calculation subsequently. Based on the improved algorithm, the VER of airglow is inversed through the tomographic technique. The full width of half maximum (FWHM) of error is 1.78% and the offset of the peak percentage error is 0.22% after 40 iterations for final VER. Comparison of assumed and retrieved VER profiles suggests that VER can be retrieved with a bias of 15% between 10 km and 90 km above the LayerMin (6384 km from the Earth center), and with a bias of 8% for altitude from 30 km to 60 km with vertical resolution of 1 km after 40 iterations. After improvements, the computation speed of VER inversion for once can be improved by 29.6 times for 700 images of 1/3 orbit, and accordingly, the processing time will be reduced from 3 hours and 11 minutes to only 6 minutes. In conclusion, the improvements to tomographic inversion of VER of airglow proposed in this paper are effective and significant.展开更多
Since the Clean Development Mechanism(CDM) under the Kyoto Protocol was initiated,China and India have overwhelmingly led other developing countries regarding CDM projects development.A comparative study of the CDM in...Since the Clean Development Mechanism(CDM) under the Kyoto Protocol was initiated,China and India have overwhelmingly led other developing countries regarding CDM projects development.A comparative study of the CDM in India and China is conducted as there are many similarities between both India and China with regard to the CDM implementation due to the fact that India is another major developing country with a large population and a potential source of GHG emissions rivaling China in the near future.Through examining the development of and legal issues for CDM projects in India,its experience and lessons regarding developing and managing CDM projects that China can critically learn are discussed.展开更多
Green supply chain is one of the trends of industry development. And performance measurement is the key to implementing the supply chain. So it is necessary to evaluate the environmental performance of supply chain .A...Green supply chain is one of the trends of industry development. And performance measurement is the key to implementing the supply chain. So it is necessary to evaluate the environmental performance of supply chain .According to the connotation of green supply chain and the standards of environmental management, this paper designs green performance measurement systems which is composed of four main factors such as waste emissions and exposure hazard, resource utilization, product recovery, and environmental reputation. And the authors delve deeply these factors so that it forms a two-level measurement system. Then the effect on the traditional performance measurement of supply chain is studied after taking greening to the supply chain leveL At last the authors apply the method of multi-level fuzzy judgment to the environmental performance measurement system. An example is given to show the judgment process.展开更多
Tillage and fertilization practices used in row crop production are thought to alter greenhouse gas emissions from soil. This study was conducted to determine the impact of fertilizer sources, land management practice...Tillage and fertilization practices used in row crop production are thought to alter greenhouse gas emissions from soil. This study was conducted to determine the impact of fertilizer sources, land management practices, and fertilizer placement methods on greenhouse gas (CO2, CH4, and N2O) emissions. A new prototype implement developed for applying poultry litter in subsurface bands in the soil was used in this study. The field site was located at the Sand Mountain Research and Extension Center in the Appalachian Plateau region of northeast Alabama, USA, on a Hartsells fine sandy loam (fine-loamy, siliceous, subactive, thermic Typic Hapludults). Measurements of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N20) emissions followed GRACEnet (greenhouse gas reduction through agricultural carbon enhancement network) protocols to assess the effects of different tillage (conventional vs. no-tillage) and fertilizer placement (subsurface banding vs. surface application) practices in a corn (Zea mays L.) cropping system. Fertilizer sources were urea-ammonium nitrate (UAN), ammonium nitrate (AN) and poultry litter (M) applied at a rate of 170 kg ha^(-1) of available N. Banding of fertilizer resulted in the greatest concentration of gaseous loss (CO2 and N2O) compared to surface applications of fertilizer. Fertilizer banding increased CO2 and N2O loss on various sampling days throughout the season with poultry litter banding emitting more gas than UAN banding. Conventional tillage practices also resulted in a higher concentration of CO2 and N2O loss when evaluating tillage by sampling day. Throughout the course of this study, CH4 flux was not affected by tillage, fertilizer source, or fertilizer placement method. These results suggest that poultry litter use and banding practices have the potential to increase greenhouse gas emissions.展开更多
High functionality given to steel products results in incremental environment loads at the steelmaking stage.However,at the stage of utilization,high-functional steel products prove more environment friendly than thei...High functionality given to steel products results in incremental environment loads at the steelmaking stage.However,at the stage of utilization,high-functional steel products prove more environment friendly than their conventional counterparts in many cases.Therefore,evaluation on contribution of steel products to environmental improvement requires an integrated approach that considers the product over its entire life cycle - life cycle assessment(LCA).This paper discusses the relationship between the improvement of steel products performance and environmental impact from the entire life cycle perspectives.The LCA method to calculate and assess contribution of high-functional steel products during the life cycle to environmental improvement is explained.Two case studies of Baoshan Iron & Steel Co.,Ltd.(Baosteel for short) are given to show that LCA is a scientific and systematic method for eco-materials evaluation or eco-design:in a power transformer,using silicon steel B30P110 to replace B30G130 can reduce carbon dioxide emissions in the region of 15.1% over the life cycle of the power transformer;tinplate steel of Baosteel for two-piece steel cans experienced six times thickness reduction from 0.280 to 0.225 mm,which results in 14.5% emission reduction over the life cycle of two-piece steel cans.It is a systematic and scientific method for evaluating on products environmental performance from life cycle perspective.展开更多
In this paper, a multi-objective particle swarm optimization (MOPSO) algorithm and a nondominated sorting genetic algorithm II (NSGA-II) are used to optimize the operating parameters of a 1.6 L, spark ignition (S...In this paper, a multi-objective particle swarm optimization (MOPSO) algorithm and a nondominated sorting genetic algorithm II (NSGA-II) are used to optimize the operating parameters of a 1.6 L, spark ignition (SI) gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks (ANNs) were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms: NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively.展开更多
基金The National Natural Science Foundation of China(No.41877240)Scientific Research Foundation of Graduate School of Southeast University(No.YBPY1930).
文摘Considering that copper mine tailings(CMTs)are commonly mixed with ordinary Portland cement,fly ash(FA),and kaolin to produce geopolymers,to make full use of CMTs,the properties of geopolymers manufactured under different material mass ratios and curing methods(standard curing,water bath curing,and 60℃curing)are evaluated with significantly increased dosage of CMTs.Porosity and unconfined compressive strength tests,X-ray diffraction,field emission scanning electron microscopy,and energy dispersive spectroscopy are used to determine the physical and mechanical properties,microstructure,and mineral composition of geopolymers.Finally,costs and CO 2 emissions of specimens with different material mass ratios during the preparation processes are compared.The results show that during the geopolymerization of low-calcium materials,various geopolymer gels,including calcium silicate,calcium silicoaluminate,and mainly sodium silicoaluminate gels,coexist.The solid waste,cost,and carbon dioxide emission reductions can reach 100%,166.3 yuan/t,and 73.3 kg/t,respectively.Under a curing condition of 60℃,the sample with a CMTs mass fraction of 70%and an FA mass fraction of 30%meets the requirements of porosity,compressive strength.The resource utilization of CMT and FA is realized in a more economical way.
文摘The in-situ instrumentation technique for measuring mercury and itsspeciation downstream a utility 100 MW pulverized coal (PC) fired boiler system was developed andconducted by the use of the Ontario hydro method (OHM) consistent with American standard test methodtogether with the semi-continuous emissions monitoring (SCEM) system as well as a mobile laboratoryfor mercury monitoring. The mercury and its speciation concentrations including participate mercuryat three locations of before air preheater, before electrostatic precipitator (ESP) and after ESPwere measured using the OHM and SCEM methods under normal operation conditions of the boiler systemas a result of firing a bituminous coal. The vapor-phase total mercury Hg(VT) concentration declinedwith the decrease of flue gas temperature because of mercury species transformation from oxidizedmercury to particulate mercury as the flue gas moved downstream from the air preheater to the ESPand after the ESP. A good agreement for Hg°, Hg^(2+) and Hg( VT) was obtained between the twomethods in the ash-free area. But in the dense particle-laden flue gas area, there appeared to be abig bias for mercury speciation owing to dust cake formed in the filter of OHM sampling probe. Theparticulateaffinity to the flue gas mercury and the impacts of sampling condition to accuracy ofmeasure were discussed.
文摘Traditional coal mine safety prediction methods are off-line and do not have dynamic prediction functions.The Support Vector Machine(SVM) is a new machine learning algorithm that has excellent properties.The least squares support vector machine(LS-SVM) algorithm is an improved algorithm of SVM.But the common LS-SVM algorithm,used directly in safety predictions,has some problems.We have first studied gas prediction problems and the basic theory of LS-SVM.Given these problems,we have investigated the affect of the time factor about safety prediction and present an on-line prediction algorithm,based on LS-SVM.Finally,given our observed data,we used the on-line algorithm to predict gas emissions and used other related algorithm to compare its performance.The simulation results have verified the validity of the new algorithm.
文摘International and national concern about detrimental climate change has generated pressure for the shipping industry to play its' role in reducing the 3.3% of global carbon emission it emits. On the 1st January, 2013, the IMO (International Maritime Organisation) enforced regulations to support the reduction of shipping carbon emissions by improving energy efficiency. These measures directly and indirectly affect the daily operations of seafarers and onshore performance and managerial personnel. Whilst the industry has made efforts to raise the awareness of many stakeholders and research has been undertaken to investigate energy efficiency barriers, little has been done to capture the opinions, needs and knowledge of seafarers. A questionnaire was distributed in the last quarter of 2011 to investigate seafarers' awareness, knowledge and motivation towards carbon emissions in general and towards shipping carbon emissions. It also investigated opinions as to which personnel have the most influence over carbon reductions and what are the most important operational improvements that can be made. The authors have collected 317 questionnaire responses. The primary benefit of this study is to support the identification of an operational strategy to improve energy efficiency, including the development of LC-EE (low carbon-energy efficiency) MET (maritime education and training), which is shown to be needed.
文摘To create evaluation methods in reclamation area according to specific conditions in coal mines, introduced the re- search trends both at home and abroad on plants' carbon fixation and oxygen release, offered, at the same time, several method models on carbon fixation and oxygen release by plants, and gave some suggestions in this field on the basis of reading the ex- periences of former experts. Finally, used biomass method and instrument measurement method to analyze carbon emission benefits in the study area.
文摘All human activities, including food production, are potentially sources of greenhouse gases (GHG) emissions. In order to provide a better understanding of how to mitigate the GHG emissions, an inventory based on different beef supply chains in the United Kingdom and in Brazil was carried out. The carbon footprint of the beef systems was calculated based on the life cycle assessment methodology. Total emissions per kg of bone-free meat were calculated at being 33.85, 33.99 and 45.17 kg of CO2e-100/kg for UK1, UK2 and Brazil farm units, respectively. Based on an average potential for carbon sequestration rate at the proportion of 12:44 for C:CO2 conversion for well managed grasslands, there is a potential sequestration of 1,980 kg of CO2/ha/year. This would potentially reduce the total emissions value for the three distinct supply chains the cases ofUKb UK2 and Brazil, respectively. as being 29.4, 28.4 and 25.4 kg C02-e 100/kg of bone-free meat for
基金Under the auspices of National High Technology Research and Development Program of China(No.2006AA12Z102)Graduate Innovation Fund of Jilin University(No.20091023)
文摘The volume emission rate (VER) of airglow can be used to investigate atmospheric processes. Satellite-based limb measurement of atmosphere is able to obtain the VER profile of airglow with high vertical resolution. However, the traditional one-dimensional retrieval techniques for VER inversion fail to retrieve horizontal structure of VER profile. Thus, the tomographic technique based on the maximum probability is applied to retrieving two-dimensional VER profile of airglow from infrared limb measurement. This technique could process the observed data with low signal-to-noise ratio caused by the observation angle of less than 180° due to the solid nature of the Earth. For saving the processing time and improving the computing speed of VER inversion, serial tables for storing the large sparse matrix for radiance simulation and a large dataset during iterative estimate of VER are presented. The index and weighting factor of line of sight (LOS) through each grid are saved in initial estimate to avoid being computed repeatedly. Furthermore, the product of observed radiance and corresponding weighting factor obtained in initial iteration is stored as weighted observed radiance for the iterative calculation subsequently. Based on the improved algorithm, the VER of airglow is inversed through the tomographic technique. The full width of half maximum (FWHM) of error is 1.78% and the offset of the peak percentage error is 0.22% after 40 iterations for final VER. Comparison of assumed and retrieved VER profiles suggests that VER can be retrieved with a bias of 15% between 10 km and 90 km above the LayerMin (6384 km from the Earth center), and with a bias of 8% for altitude from 30 km to 60 km with vertical resolution of 1 km after 40 iterations. After improvements, the computation speed of VER inversion for once can be improved by 29.6 times for 700 images of 1/3 orbit, and accordingly, the processing time will be reduced from 3 hours and 11 minutes to only 6 minutes. In conclusion, the improvements to tomographic inversion of VER of airglow proposed in this paper are effective and significant.
基金supported by the MOE (Ministry of Education in China) Project of Humanities and Social Sciences (Project No.11YJC820045)
文摘Since the Clean Development Mechanism(CDM) under the Kyoto Protocol was initiated,China and India have overwhelmingly led other developing countries regarding CDM projects development.A comparative study of the CDM in India and China is conducted as there are many similarities between both India and China with regard to the CDM implementation due to the fact that India is another major developing country with a large population and a potential source of GHG emissions rivaling China in the near future.Through examining the development of and legal issues for CDM projects in India,its experience and lessons regarding developing and managing CDM projects that China can critically learn are discussed.
文摘Green supply chain is one of the trends of industry development. And performance measurement is the key to implementing the supply chain. So it is necessary to evaluate the environmental performance of supply chain .According to the connotation of green supply chain and the standards of environmental management, this paper designs green performance measurement systems which is composed of four main factors such as waste emissions and exposure hazard, resource utilization, product recovery, and environmental reputation. And the authors delve deeply these factors so that it forms a two-level measurement system. Then the effect on the traditional performance measurement of supply chain is studied after taking greening to the supply chain leveL At last the authors apply the method of multi-level fuzzy judgment to the environmental performance measurement system. An example is given to show the judgment process.
基金Supported by the United States Department of Agriculture, Agricultural Research Service (USDA-ARS) fundsthe Alabama Wheat and Feed Grains Commodity Grant, USA
文摘Tillage and fertilization practices used in row crop production are thought to alter greenhouse gas emissions from soil. This study was conducted to determine the impact of fertilizer sources, land management practices, and fertilizer placement methods on greenhouse gas (CO2, CH4, and N2O) emissions. A new prototype implement developed for applying poultry litter in subsurface bands in the soil was used in this study. The field site was located at the Sand Mountain Research and Extension Center in the Appalachian Plateau region of northeast Alabama, USA, on a Hartsells fine sandy loam (fine-loamy, siliceous, subactive, thermic Typic Hapludults). Measurements of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N20) emissions followed GRACEnet (greenhouse gas reduction through agricultural carbon enhancement network) protocols to assess the effects of different tillage (conventional vs. no-tillage) and fertilizer placement (subsurface banding vs. surface application) practices in a corn (Zea mays L.) cropping system. Fertilizer sources were urea-ammonium nitrate (UAN), ammonium nitrate (AN) and poultry litter (M) applied at a rate of 170 kg ha^(-1) of available N. Banding of fertilizer resulted in the greatest concentration of gaseous loss (CO2 and N2O) compared to surface applications of fertilizer. Fertilizer banding increased CO2 and N2O loss on various sampling days throughout the season with poultry litter banding emitting more gas than UAN banding. Conventional tillage practices also resulted in a higher concentration of CO2 and N2O loss when evaluating tillage by sampling day. Throughout the course of this study, CH4 flux was not affected by tillage, fertilizer source, or fertilizer placement method. These results suggest that poultry litter use and banding practices have the potential to increase greenhouse gas emissions.
基金the Training Program Fund for Young Teachers in Shanghai Higher Education Institutions (No.405ZK11YQ15)the Scientific Research Starting Foundation for Recruiting Talents of Shanghai Institute of Technology(No.1020K116079)
文摘High functionality given to steel products results in incremental environment loads at the steelmaking stage.However,at the stage of utilization,high-functional steel products prove more environment friendly than their conventional counterparts in many cases.Therefore,evaluation on contribution of steel products to environmental improvement requires an integrated approach that considers the product over its entire life cycle - life cycle assessment(LCA).This paper discusses the relationship between the improvement of steel products performance and environmental impact from the entire life cycle perspectives.The LCA method to calculate and assess contribution of high-functional steel products during the life cycle to environmental improvement is explained.Two case studies of Baoshan Iron & Steel Co.,Ltd.(Baosteel for short) are given to show that LCA is a scientific and systematic method for eco-materials evaluation or eco-design:in a power transformer,using silicon steel B30P110 to replace B30G130 can reduce carbon dioxide emissions in the region of 15.1% over the life cycle of the power transformer;tinplate steel of Baosteel for two-piece steel cans experienced six times thickness reduction from 0.280 to 0.225 mm,which results in 14.5% emission reduction over the life cycle of two-piece steel cans.It is a systematic and scientific method for evaluating on products environmental performance from life cycle perspective.
文摘In this paper, a multi-objective particle swarm optimization (MOPSO) algorithm and a nondominated sorting genetic algorithm II (NSGA-II) are used to optimize the operating parameters of a 1.6 L, spark ignition (SI) gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks (ANNs) were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms: NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively.