The double moral hazard of "company + farmer" and the time preference cost of company and farmer was analyzed. According to static game model, it re-vealed that the reason for low compliance rate of "company + fa...The double moral hazard of "company + farmer" and the time preference cost of company and farmer was analyzed. According to static game model, it re-vealed that the reason for low compliance rate of "company + farmer" model was the existence of market risk, namely, the fluctuation of market price, and the stable market price in contracts was actualy a kind of interval, instead of a specific value. Furthermore, the effect of default penalty, market transaction cost and time prefer-ence cost on the stability of contract was studied. The results showed that default penalty, market transaction cost and time preference cost had positive influence on the price interval range of a contract.展开更多
In this study, the performance of a sequencing batch biofilm reactor(SBBR) for removal of nitrogen and phosphorus from swine wastewater was evaluated. The replacement rate of wastewater was set at 12.5% throughout the...In this study, the performance of a sequencing batch biofilm reactor(SBBR) for removal of nitrogen and phosphorus from swine wastewater was evaluated. The replacement rate of wastewater was set at 12.5% throughout the experiment. The anaerobic and aerobic times were 3 h and 7 h, respectively, and the dissolved oxygen concentration of the aerobic phase was about 3.95 mg·L-1. The SBBR process demonstrated good performance in treating swine wastewater. The percentage removal of total chemical oxygen demand(COD), ammonia nitrogen(NH4+-N), total nitrogen(TN), and total phosphorus(TP) was 98.2%, 95.7%, 95.6%, and 96.2% at effluent concentrations of COD85.6 mg·L-1, NH4+-N 35.22 mg·L-1, TN 44.64 mg·L-1, and TP 1.13 mg·L-1, respectively. Simultaneous nitrification and denitrification phenomenon was observed. Further improvement in removal efficiency of NH4+-N and TN occurred at COD/TN ratio of 11:1, with effluent concentrations at NH4+-N 18.5 mg·L-1and TN 34 mg·L-1, while no such improvement in COD and TP removal was found. Microbial electron microscopy analysis showed that the filler surface was covered with a thick biofilm, forming an anaerobic–aerobic microenvironment and facilitating the removal of nitrogen, phosphorus and organic matters. A long-term experiment(15 weeks) showed that stable removal efficiency for N and P could be achieved in the SBBR system.展开更多
For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste...For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste-water. In this study, an on-line information system for phosphorus removal processes was established. Based on the analysis for four systems with different ecological community structures and two operation modes, anaerobic-aerobic process and anaerobic-anaerobic process, the characteristic patterns of oxidation-reduction potential (ORP) and pH were related to phosphorous dynamics in the anaerobic, anoxic and aerobic phases, for determination of the end of phosphorous removal. In the operation mode of anaerobic-aerobic process, the pH profile in the anaerobic phase was used to estimate the relative amount of phosphorous accumulating organisms (PAOs) and glycogen accumulat-ing organisms (GAOs), which is beneficial to early detection of ecology community shifts. The on-line sensor val-ues of pH and ORP may be used as the parameters to adjust the duration for phosphorous removal and community shifts to cope with influent variations and maintain appropriate operation conditions.展开更多
A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m (TiO2): m (H3PW6Mo6O40) is 1:2.0, volume of water is 30 mL, the reflux react...A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m (TiO2): m (H3PW6Mo6O40) is 1:2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn (aldehyde(ketone)): n (glycol), catalyst dosage and reaction time on yield were investigated. Optimal conditions were: n(aldehyde (ketone)): n (glycol)=1.0 : 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%展开更多
A"better life in the new era,"a proposition unique to 21 st century Marxism,is based on the historical originality of socialism with Chinese characteristics.Along with the transformation of the main contradi...A"better life in the new era,"a proposition unique to 21 st century Marxism,is based on the historical originality of socialism with Chinese characteristics.Along with the transformation of the main contradictions in Chinese society,"a better life in the new era"has become a new life-form.Of course,the new life-form and new development ideas are complementary.On the one hand,the proposition of the new development ideas is based on the transformation of the new life-forms,so the inherent purport of the two is closely related;on the other,the proposition of such ideas will further promote the construction of"a better life in the new era"at the level of practice,and will play a key leading role in the resolution of major social contradictions.Therefore,to comprehensively understand the revolutionary significance of a"better life in the new era"under the guidance of the new development principles,we must gain an intrinsic grasp of the many forms of a"better life in the new era,"including its actors,forms of occurrence,forms of realization and external forms.They have as their theoretical support such concepts as"the people as themain force,the ruling Party as the guide,""transformation of contradictions,integration of supply and demand,""labor orientation,co-creation and sharing,"and"homogeneous ideals extended worldwide."Together,these constitute a unique Chinese style.In the building of socialism with Chinese characteristics,or modernization,only the sublation of"objective[sachlicher]dependence"and adherence to the practical intention of"free individuality"can fulfill the"return"of a"better life in the new era"toward"man himself,"and achieve value guidance for the Chinese road.展开更多
The well posedness of best simultaneous approximation problems is considered. We establish the generic results on the well posedness of the best simultaneous approximation problems for any closed weakly compact nonemp...The well posedness of best simultaneous approximation problems is considered. We establish the generic results on the well posedness of the best simultaneous approximation problems for any closed weakly compact nonempty subset in a strictly convex Kadec Banach space. Further, we prove that the set of all points inE(G) such that the best simultaneous approximation problems are not well posed is a u- porous set inE(G) whenX is a uniformly convex Banach space. In addition, we also investigate the generic property of the ambiguous loci of the best simultaneous approximation.展开更多
Time, cost, and quality are three key control factors in rockfill dam construction, and the tradeoff among them is important. Research has focused on the construction time-cost-quality tradeoff for the planning or des...Time, cost, and quality are three key control factors in rockfill dam construction, and the tradeoff among them is important. Research has focused on the construction time-cost-quality tradeoff for the planning or design phase, built on static empirical data. However, due to its intrinsic uncertainties, rockfill dam construction is a dynamic process which requires the tradeoffto adjust dynamically to changes in construction conditions. In this study, a dynamic time-cost-quality tradeoff (DTCQT) method is proposed to balance time, cost, and quality at any stage of the construction process. A time-cost-quality tradeoff model is established that considers time cost and quality cost. Time, cost, and quality are dynamically estimated based on real-time monitoring. The analytic hierarchy process (AHP) method is applied to quantify the decision preferences among time, cost, and quality as objective weights. In addition, an improved non-dominated sorting genetic algorithm (NSGA-II) coupled with the technique for order preference by similarity to ideal solution (TOPSIS) method is used to search for the optimal compromise solution. A case study project is analyzed to demonstrate the applicability of the method, and the efficiency of the proposed optimization method is compared with that of the linear weighted sum (LWS) and NSGA-II.展开更多
基金Supported by Humanities and Social Sciences of Ministry of Education(12YJC630050)Soft Science Bidding Project of Ministry of Agriculture(20140203)+1 种基金Jiangxi Soft Science Fund(20141BBA10065)Jiangxi’s Jiangxi Provincial Education Department(GJJ13727)~~
文摘The double moral hazard of "company + farmer" and the time preference cost of company and farmer was analyzed. According to static game model, it re-vealed that the reason for low compliance rate of "company + farmer" model was the existence of market risk, namely, the fluctuation of market price, and the stable market price in contracts was actualy a kind of interval, instead of a specific value. Furthermore, the effect of default penalty, market transaction cost and time prefer-ence cost on the stability of contract was studied. The results showed that default penalty, market transaction cost and time preference cost had positive influence on the price interval range of a contract.
基金Supported by the Beijing Municipal Science and Technology Program(Z121100001512008)
文摘In this study, the performance of a sequencing batch biofilm reactor(SBBR) for removal of nitrogen and phosphorus from swine wastewater was evaluated. The replacement rate of wastewater was set at 12.5% throughout the experiment. The anaerobic and aerobic times were 3 h and 7 h, respectively, and the dissolved oxygen concentration of the aerobic phase was about 3.95 mg·L-1. The SBBR process demonstrated good performance in treating swine wastewater. The percentage removal of total chemical oxygen demand(COD), ammonia nitrogen(NH4+-N), total nitrogen(TN), and total phosphorus(TP) was 98.2%, 95.7%, 95.6%, and 96.2% at effluent concentrations of COD85.6 mg·L-1, NH4+-N 35.22 mg·L-1, TN 44.64 mg·L-1, and TP 1.13 mg·L-1, respectively. Simultaneous nitrification and denitrification phenomenon was observed. Further improvement in removal efficiency of NH4+-N and TN occurred at COD/TN ratio of 11:1, with effluent concentrations at NH4+-N 18.5 mg·L-1and TN 34 mg·L-1, while no such improvement in COD and TP removal was found. Microbial electron microscopy analysis showed that the filler surface was covered with a thick biofilm, forming an anaerobic–aerobic microenvironment and facilitating the removal of nitrogen, phosphorus and organic matters. A long-term experiment(15 weeks) showed that stable removal efficiency for N and P could be achieved in the SBBR system.
基金Supported by the Project of Scientific Research Base and Scientific Innovation Platform of Beijing Municipal Education Com-mission (PXM2008_014204_050843)the National Natural Science Foundation of China (50808004)the DoctoralStartup Research Program of Beijing University of Technology
文摘For efficient energy consumption and control of effluent quality, the cycle duration for a sequencing batch reactor (SBR) needs to be adjusted by real-time control according to the characteristics and loading of waste-water. In this study, an on-line information system for phosphorus removal processes was established. Based on the analysis for four systems with different ecological community structures and two operation modes, anaerobic-aerobic process and anaerobic-anaerobic process, the characteristic patterns of oxidation-reduction potential (ORP) and pH were related to phosphorous dynamics in the anaerobic, anoxic and aerobic phases, for determination of the end of phosphorous removal. In the operation mode of anaerobic-aerobic process, the pH profile in the anaerobic phase was used to estimate the relative amount of phosphorous accumulating organisms (PAOs) and glycogen accumulat-ing organisms (GAOs), which is beneficial to early detection of ecology community shifts. The on-line sensor val-ues of pH and ORP may be used as the parameters to adjust the duration for phosphorous removal and community shifts to cope with influent variations and maintain appropriate operation conditions.
基金Acknowledgements: This work was financially supported by the Natural Science Foundation of Hubei Province, China (No. 2005ABA053) and the National Natural Science Foundation of China (No. 20471044).
文摘A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m (TiO2): m (H3PW6Mo6O40) is 1:2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn (aldehyde(ketone)): n (glycol), catalyst dosage and reaction time on yield were investigated. Optimal conditions were: n(aldehyde (ketone)): n (glycol)=1.0 : 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%
文摘A"better life in the new era,"a proposition unique to 21 st century Marxism,is based on the historical originality of socialism with Chinese characteristics.Along with the transformation of the main contradictions in Chinese society,"a better life in the new era"has become a new life-form.Of course,the new life-form and new development ideas are complementary.On the one hand,the proposition of the new development ideas is based on the transformation of the new life-forms,so the inherent purport of the two is closely related;on the other,the proposition of such ideas will further promote the construction of"a better life in the new era"at the level of practice,and will play a key leading role in the resolution of major social contradictions.Therefore,to comprehensively understand the revolutionary significance of a"better life in the new era"under the guidance of the new development principles,we must gain an intrinsic grasp of the many forms of a"better life in the new era,"including its actors,forms of occurrence,forms of realization and external forms.They have as their theoretical support such concepts as"the people as themain force,the ruling Party as the guide,""transformation of contradictions,integration of supply and demand,""labor orientation,co-creation and sharing,"and"homogeneous ideals extended worldwide."Together,these constitute a unique Chinese style.In the building of socialism with Chinese characteristics,or modernization,only the sublation of"objective[sachlicher]dependence"and adherence to the practical intention of"free individuality"can fulfill the"return"of a"better life in the new era"toward"man himself,"and achieve value guidance for the Chinese road.
基金the National Natural Science Foundation of China (Grant No. 19971013) and Natural Science Foundation of Jiangsu Province (Grant No. BK99001) .
文摘The well posedness of best simultaneous approximation problems is considered. We establish the generic results on the well posedness of the best simultaneous approximation problems for any closed weakly compact nonempty subset in a strictly convex Kadec Banach space. Further, we prove that the set of all points inE(G) such that the best simultaneous approximation problems are not well posed is a u- porous set inE(G) whenX is a uniformly convex Banach space. In addition, we also investigate the generic property of the ambiguous loci of the best simultaneous approximation.
基金Project supported by the Innovative Research Groups of the National Natural Science Foundation of China (No. 51621092), the National Basic Research Program (973 Program) of China (No. 2013CB035904), and the Natural Science Foundation of China (No. 51439005)
文摘Time, cost, and quality are three key control factors in rockfill dam construction, and the tradeoff among them is important. Research has focused on the construction time-cost-quality tradeoff for the planning or design phase, built on static empirical data. However, due to its intrinsic uncertainties, rockfill dam construction is a dynamic process which requires the tradeoffto adjust dynamically to changes in construction conditions. In this study, a dynamic time-cost-quality tradeoff (DTCQT) method is proposed to balance time, cost, and quality at any stage of the construction process. A time-cost-quality tradeoff model is established that considers time cost and quality cost. Time, cost, and quality are dynamically estimated based on real-time monitoring. The analytic hierarchy process (AHP) method is applied to quantify the decision preferences among time, cost, and quality as objective weights. In addition, an improved non-dominated sorting genetic algorithm (NSGA-II) coupled with the technique for order preference by similarity to ideal solution (TOPSIS) method is used to search for the optimal compromise solution. A case study project is analyzed to demonstrate the applicability of the method, and the efficiency of the proposed optimization method is compared with that of the linear weighted sum (LWS) and NSGA-II.