In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of ap...In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/(m2·s). The proportions of lateral shoot of bearing part were 81% and 75% respectively.展开更多
[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,ph...[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton's community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index's range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration.展开更多
The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, an...The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, and densities of states of these metals were calculated using the plane-wave pseudopotential method in DFT. Results were compared with those of projector augmented wave method, CALPHAD method, and experiments. Total energy and electronic structure analyses showed that valence electrons mostly transferred from s to p or d state, changing obviously with both the crystal structure and the elemental period number from V to Ta and leading to stronger cohesion, higher cohesive energy and more stable lattice of heavier metals.展开更多
The adsorption of dibenzofuran on three commercial granular activated carbons (ACs) was investigated by dynamic experiment to correlate the adsorption equilibrium and kinetics with the structure of activated carbons.P...The adsorption of dibenzofuran on three commercial granular activated carbons (ACs) was investigated by dynamic experiment to correlate the adsorption equilibrium and kinetics with the structure of activated carbons.Physical properties including surface area, average pore diameter, micropore area and micropore volume of the activated carbons were characterized by N2 adsorption experiment on ASAP2010. To calculate the adsorption parameters, adsorption isotherm data were fitted to the Langmuir equation, and adsorption kinetic data were fitted to the linear driving force (LDF) diffusion model. From the correlation results, it is concluded that the adsorption equilibrium and diffusion coefficient of dibenzofuran on activated carbon are controlled respectively by the total adsorbent surface area and the adsorbent pore diameter.展开更多
In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters ...In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters for shield cutterhead is formulated,based on the complex engineering technical requirements. In the model, as the objective function of the model is a composite function of the strength and stiffness, the response surface method is applied to formulate the approximate function of objective function in order to reduce the solution scale of optimal problem. A multi-objective genetic algorithm is used to solve the cutterhead structure design problem and the change rule of the stress-strain with various structural parameters as well as their optimal values were researched under specific geological conditions. The results show that compared with original cutterhead structure scheme, the obtained optimal scheme of the cutterhead structure can greatly improve the strength and stiffness of the cutterhead, which can be seen from the reduction of its maximum equivalent stress by 21.2%, that of its maximum deformation by 0.75%, and that of its mass by 1.04%.展开更多
The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of ...The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of symmetric tridiagonal matrix. The multisection method for solving the generalized eigenproblem applied significantly in many science and engineering domains has not been studied. The parallel region preserving multisection method (PRM for short) for solving generalized eigenproblems of large sparse and real symmetric matrix is presented in this paper. This method not only retains the advantages of the conventional determinant search method (DS for short), but also overcomes its disadvantages such as leaking roots and disconvergence. We have tested the method on the YH 1 vector computer, and compared it with the parallel region preserving determinant search method the parallel region preserving bisection method (PRB for short). The numerical results show that PRM has a higher speed up, for instance, it attains the speed up of 7.7 when the scale of the problem is 2 114 and the eigenpair found is 3, and PRM is superior to PRB when the scale of the problem is large.展开更多
To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural ...To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural fatigue damage reliability were derived. Fatigue damage reliability analysis of some critical members of the Nanjing Yangtze river bridge was carried out by using the strain-time histories measured by the structural health monitoring system of the bridge. The corresponding stress spectra were obtained by the real-time rain-flow counting method. Results of fatigue damage were calculated respectively by the reliability method at different reliability and compared with Miner’s rule. The results show that the fatigue damage of critical members of the Nanjing Yangtze river bridge is very small due to its low live-load stress level.展开更多
The chemistry version of the Weather Re- search and Forecasting model (WRF/Chem) was coupled with the anthropogenic emission inventory of David Streets to investigate the impacts of secondary aerosols on a persisten...The chemistry version of the Weather Re- search and Forecasting model (WRF/Chem) was coupled with the anthropogenic emission inventory of David Streets to investigate the impacts of secondary aerosols on a persistent fog event from 25 to 26 October 2007, in Northem China. The spatial distribution of the simulated fog is consistent with satellite observations, and the time-height distributions of the simulated boundary layer where the fog formed are also in good agreement with these observations. The sensitivity studies show that the secondary aerosols of SO4, NO3, and NH4 formed from gaseous precursors of SO2, NOx, and NH3 had substantial impacts on the formation processes and microphysical structure of the fog event. The decrease of the secondary aerosols obviously reduced the liquid water path and column droplet number concentration of the fog below the 1-km layer, and the corresponding area-averaged liquid water path and droplet number concentration of the fog decreased by 43% and 79%, respectively. The concentra- tions of NOx and NO3 were found to be extremely high in this case. The concentration of interstitial aerosol NO3 was much higher than the SO4 and NH4, but the concentration of SO4 was highest in the cloud-borne aerosols. The average activation ratios for SO4, NO3, and NH4 were 34%, 31%, and 30%, respectively, and the maximum ra- tios reached 62%, 86%, and 55% during the fog episode.展开更多
ISO 9000 certification has been considered as an effective competitive edge for manufacturing industries. In Hong Kong, the ISO 9000 certification has been widely adopted and extended to service industries for the so...ISO 9000 certification has been considered as an effective competitive edge for manufacturing industries. In Hong Kong, the ISO 9000 certification has been widely adopted and extended to service industries for the sole purpose of enhancing corporate image. However, complaints have been voiced by many certified organizations about increasing paperwork, non direct labour and excessive resources channelled into non core business. This paper is to propound the integrated management system, a single management system focusing on business purpose yet being flexible enough to integrate the requirements of various management standards such as the ISO 9000, ISO 14000 and future ISO 18000. This paper describes how the proposed system could be implemented to achieve the desired business results.展开更多
Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSding...Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.展开更多
In the quotient space theory of granular computing,the universe structure is assumed to be a topology,therefore,its application is still limited.In this study,based on the quotient space model,the universe structure i...In the quotient space theory of granular computing,the universe structure is assumed to be a topology,therefore,its application is still limited.In this study,based on the quotient space model,the universe structure is assumed as an algebra instead of a topology.As to obtain the algebraic quotient operator,the granulation must be uniquely determined by a congruence relation,and all the congruence relations form a complete semi-order lattice,which is the theoretical basis of granularities ' completeness.When the given equivalence relation is not a congruence relation,it defines the concepts of upper quotient and lower quotient,and discusses some of their properties which demonstrate that falsity preserving principle and truth preserving principle are still valid.Finally,it presents the algorithms and example of upper quotient and lower quotient.The work extends the quotient space theory from structure,and provides theoretical basis for the combination of the quotient space theory and the algebra theory.展开更多
We give here an overview of the orbital-flee density functional theory that is used for modeling atoms and molecules. We review typical approximations to the kinetic energy, exchange-correlation corrections to the k...We give here an overview of the orbital-flee density functional theory that is used for modeling atoms and molecules. We review typical approximations to the kinetic energy, exchange-correlation corrections to the kinetic and Hartree energies, and constructions of the pseudopotentials. We discuss numerical discretizations for the orbital-free methods and include several numerical results for illustrations.展开更多
基金Supported by Special Fund for Modern Agricultural Industry Technology System(CARS-28)~~
文摘In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/(m2·s). The proportions of lateral shoot of bearing part were 81% and 75% respectively.
基金Supported by Major Subject of National Science and Technology(2009ZX07317-006 )Shanghai Key Scientific and Technological Issues (062312019)~~
文摘[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton's community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index's range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration.
基金ACKNOWLEDGMENTS This work was supported by the Doctoral Discipline Foundation of the Ministry of Education of China (No.20070533118) and the National Natural Science Foundation of China (No.50871124). The authors acknowledge Dr. Y. Z. Nie for his useful discussion in calculations.
文摘The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, and densities of states of these metals were calculated using the plane-wave pseudopotential method in DFT. Results were compared with those of projector augmented wave method, CALPHAD method, and experiments. Total energy and electronic structure analyses showed that valence electrons mostly transferred from s to p or d state, changing obviously with both the crystal structure and the elemental period number from V to Ta and leading to stronger cohesion, higher cohesive energy and more stable lattice of heavier metals.
文摘The adsorption of dibenzofuran on three commercial granular activated carbons (ACs) was investigated by dynamic experiment to correlate the adsorption equilibrium and kinetics with the structure of activated carbons.Physical properties including surface area, average pore diameter, micropore area and micropore volume of the activated carbons were characterized by N2 adsorption experiment on ASAP2010. To calculate the adsorption parameters, adsorption isotherm data were fitted to the Langmuir equation, and adsorption kinetic data were fitted to the linear driving force (LDF) diffusion model. From the correlation results, it is concluded that the adsorption equilibrium and diffusion coefficient of dibenzofuran on activated carbon are controlled respectively by the total adsorbent surface area and the adsorbent pore diameter.
基金Project(51074180) supported by the National Natural Science Foundation of ChinaProject(2012AA041801) supported by the National High Technology Research and Development Program of China+2 种基金Project(2007CB714002) supported by the National Basic Research Program of ChinaProject(2013GK3003) supported by the Technology Support Plan of Hunan Province,ChinaProject(2010FJ1002) supported by Hunan Science and Technology Major Program,China
文摘In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters for shield cutterhead is formulated,based on the complex engineering technical requirements. In the model, as the objective function of the model is a composite function of the strength and stiffness, the response surface method is applied to formulate the approximate function of objective function in order to reduce the solution scale of optimal problem. A multi-objective genetic algorithm is used to solve the cutterhead structure design problem and the change rule of the stress-strain with various structural parameters as well as their optimal values were researched under specific geological conditions. The results show that compared with original cutterhead structure scheme, the obtained optimal scheme of the cutterhead structure can greatly improve the strength and stiffness of the cutterhead, which can be seen from the reduction of its maximum equivalent stress by 21.2%, that of its maximum deformation by 0.75%, and that of its mass by 1.04%.
文摘The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of symmetric tridiagonal matrix. The multisection method for solving the generalized eigenproblem applied significantly in many science and engineering domains has not been studied. The parallel region preserving multisection method (PRM for short) for solving generalized eigenproblems of large sparse and real symmetric matrix is presented in this paper. This method not only retains the advantages of the conventional determinant search method (DS for short), but also overcomes its disadvantages such as leaking roots and disconvergence. We have tested the method on the YH 1 vector computer, and compared it with the parallel region preserving determinant search method the parallel region preserving bisection method (PRB for short). The numerical results show that PRM has a higher speed up, for instance, it attains the speed up of 7.7 when the scale of the problem is 2 114 and the eigenpair found is 3, and PRM is superior to PRB when the scale of the problem is large.
基金Project(2001G025) supported by the Foundation of the Science and Technology Section of Ministry of Rail way of Chinaproject(2005) supported by the Postdoctoral Foundation of Central South University
文摘To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural fatigue damage reliability were derived. Fatigue damage reliability analysis of some critical members of the Nanjing Yangtze river bridge was carried out by using the strain-time histories measured by the structural health monitoring system of the bridge. The corresponding stress spectra were obtained by the real-time rain-flow counting method. Results of fatigue damage were calculated respectively by the reliability method at different reliability and compared with Miner’s rule. The results show that the fatigue damage of critical members of the Nanjing Yangtze river bridge is very small due to its low live-load stress level.
基金supported by the National Meteorology Public Welfare Industry Research Project(GYHY200806001)the National Science and Technology Support Program (2006BAC12B03)
文摘The chemistry version of the Weather Re- search and Forecasting model (WRF/Chem) was coupled with the anthropogenic emission inventory of David Streets to investigate the impacts of secondary aerosols on a persistent fog event from 25 to 26 October 2007, in Northem China. The spatial distribution of the simulated fog is consistent with satellite observations, and the time-height distributions of the simulated boundary layer where the fog formed are also in good agreement with these observations. The sensitivity studies show that the secondary aerosols of SO4, NO3, and NH4 formed from gaseous precursors of SO2, NOx, and NH3 had substantial impacts on the formation processes and microphysical structure of the fog event. The decrease of the secondary aerosols obviously reduced the liquid water path and column droplet number concentration of the fog below the 1-km layer, and the corresponding area-averaged liquid water path and droplet number concentration of the fog decreased by 43% and 79%, respectively. The concentra- tions of NOx and NO3 were found to be extremely high in this case. The concentration of interstitial aerosol NO3 was much higher than the SO4 and NH4, but the concentration of SO4 was highest in the cloud-borne aerosols. The average activation ratios for SO4, NO3, and NH4 were 34%, 31%, and 30%, respectively, and the maximum ra- tios reached 62%, 86%, and 55% during the fog episode.
文摘ISO 9000 certification has been considered as an effective competitive edge for manufacturing industries. In Hong Kong, the ISO 9000 certification has been widely adopted and extended to service industries for the sole purpose of enhancing corporate image. However, complaints have been voiced by many certified organizations about increasing paperwork, non direct labour and excessive resources channelled into non core business. This paper is to propound the integrated management system, a single management system focusing on business purpose yet being flexible enough to integrate the requirements of various management standards such as the ISO 9000, ISO 14000 and future ISO 18000. This paper describes how the proposed system could be implemented to achieve the desired business results.
基金The project supported by Tianyuan Foundation for Mathematics under Grant No. 10626016 of National Natural Science Foundation of China, China Postdoctoral Science Foundation, Beijing Jiao-Wei Key Project under Grant No. KZ 200310028010, and National Natural Science Foundation of China under Grant No. 10375038
文摘Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.
基金Supported by the National Natural Science Foundation of China(No.61173052)the Natural Science Foundation of Hunan Province(No.14JJ4007)
文摘In the quotient space theory of granular computing,the universe structure is assumed to be a topology,therefore,its application is still limited.In this study,based on the quotient space model,the universe structure is assumed as an algebra instead of a topology.As to obtain the algebraic quotient operator,the granulation must be uniquely determined by a congruence relation,and all the congruence relations form a complete semi-order lattice,which is the theoretical basis of granularities ' completeness.When the given equivalence relation is not a congruence relation,it defines the concepts of upper quotient and lower quotient,and discusses some of their properties which demonstrate that falsity preserving principle and truth preserving principle are still valid.Finally,it presents the algorithms and example of upper quotient and lower quotient.The work extends the quotient space theory from structure,and provides theoretical basis for the combination of the quotient space theory and the algebra theory.
基金supported by the National Science Foundation of China under the grant 10425105the National Basic Research Program under the grant 2005CB321704.
文摘We give here an overview of the orbital-flee density functional theory that is used for modeling atoms and molecules. We review typical approximations to the kinetic energy, exchange-correlation corrections to the kinetic and Hartree energies, and constructions of the pseudopotentials. We discuss numerical discretizations for the orbital-free methods and include several numerical results for illustrations.