Differential evolution (DE) is a global optimizer for continuous design variables. To enhance DE, it is necessary to handle discrete design variables. In this paper, a discrete differential evolution (DDE) algorit...Differential evolution (DE) is a global optimizer for continuous design variables. To enhance DE, it is necessary to handle discrete design variables. In this paper, a discrete differential evolution (DDE) algorithm is proposed to handle discrete design variables The proposed DDE is based on the DE/l/rand/bin method. In the proposed DDE, the mutation ratio is regarded as the exchange probability, and thus, no modifications of DE/l/rand/bin are required. In addition, in order to maintain diversity through the search process, we initialize all search points. By introducing the initialization of all search points, global or quasi-optimum solution can be found. We validate the proposed DDE by applying it to several benchmark problems.展开更多
A mathematical model of the kinetics of thin-layer separation of granular materials by size stacked sieve classifiers based on the theory of Markov processes is constructed. The probability of screening in a cell in t...A mathematical model of the kinetics of thin-layer separation of granular materials by size stacked sieve classifiers based on the theory of Markov processes is constructed. The probability of screening in a cell in the shape and size of the holes and particle sieve material shared with the influence of the relative speed of their movement was determined. Residues on whole meal with sieves were identified by a kinetic model and numerical calculations, the efficacy of separation.展开更多
The process of use catalyst or functional material that contains iron ion to weaken -O-H-O- hydrogen bond of the thick oil to reduce viscidity or crack, in aspects of the ion charge. covalent bond order, total energy ...The process of use catalyst or functional material that contains iron ion to weaken -O-H-O- hydrogen bond of the thick oil to reduce viscidity or crack, in aspects of the ion charge. covalent bond order, total energy and the average distance of Fe-O. is studied with density function theory and discrete variational method (DFT-DVM), one of the first principle methods. With the decrease of the distance of Fe-O. the charge of Fe ion increases, the charge of hydrogen ion decreases, and hydrogen bond is weakened. There are obvious and more stable effects to use the catalyst that contains multiple metal ions or increase the catalyst amount in weakening hydrogen bond of the thick oil. This theoretic work is helpful to exploit and process the thick oil of petroleum and maybe overcome the crisis of petroleum energy is approaching to us.展开更多
Discontinuous deformation analysis (DDA) method is a newly developed discrete element method which employs the implicit time-integration scheme to solve the governing equations and the open-close iteration (OCI) m...Discontinuous deformation analysis (DDA) method is a newly developed discrete element method which employs the implicit time-integration scheme to solve the governing equations and the open-close iteration (OCI) method to deal with contact prob- lem, its computational efficiency is relatively low. However, spherical element based discontinuous deformation analysis (SDDA), which uses very simple contact type like point-to-point contact, has higher calculation speed. In the framework of SDDA, this paper presents a very simple contact calculation approach by removing the OCI scheme and by adopting the maximal displacement increment (MDI). Through some verification examples, it is proved that the proposed method is correct and effective, and a higher computational efficiency is obtained.展开更多
文摘Differential evolution (DE) is a global optimizer for continuous design variables. To enhance DE, it is necessary to handle discrete design variables. In this paper, a discrete differential evolution (DDE) algorithm is proposed to handle discrete design variables The proposed DDE is based on the DE/l/rand/bin method. In the proposed DDE, the mutation ratio is regarded as the exchange probability, and thus, no modifications of DE/l/rand/bin are required. In addition, in order to maintain diversity through the search process, we initialize all search points. By introducing the initialization of all search points, global or quasi-optimum solution can be found. We validate the proposed DDE by applying it to several benchmark problems.
文摘A mathematical model of the kinetics of thin-layer separation of granular materials by size stacked sieve classifiers based on the theory of Markov processes is constructed. The probability of screening in a cell in the shape and size of the holes and particle sieve material shared with the influence of the relative speed of their movement was determined. Residues on whole meal with sieves were identified by a kinetic model and numerical calculations, the efficacy of separation.
基金Acknowledgments: Thanks for the subsidization by the National Science Foundation of China (No. 50774070), Ministry of Education of China (PCSIRT0644) and Open Fund of the State Key Lab of Theoretical & Computational Chemistry.
文摘The process of use catalyst or functional material that contains iron ion to weaken -O-H-O- hydrogen bond of the thick oil to reduce viscidity or crack, in aspects of the ion charge. covalent bond order, total energy and the average distance of Fe-O. is studied with density function theory and discrete variational method (DFT-DVM), one of the first principle methods. With the decrease of the distance of Fe-O. the charge of Fe ion increases, the charge of hydrogen ion decreases, and hydrogen bond is weakened. There are obvious and more stable effects to use the catalyst that contains multiple metal ions or increase the catalyst amount in weakening hydrogen bond of the thick oil. This theoretic work is helpful to exploit and process the thick oil of petroleum and maybe overcome the crisis of petroleum energy is approaching to us.
基金supported by the National Basic Research Program of China("973" Project)(Grant Nos.2014CB046904&2014CB047101)the National Natural Science Foundation of China(Grant Nos.51479191&51509242)
文摘Discontinuous deformation analysis (DDA) method is a newly developed discrete element method which employs the implicit time-integration scheme to solve the governing equations and the open-close iteration (OCI) method to deal with contact prob- lem, its computational efficiency is relatively low. However, spherical element based discontinuous deformation analysis (SDDA), which uses very simple contact type like point-to-point contact, has higher calculation speed. In the framework of SDDA, this paper presents a very simple contact calculation approach by removing the OCI scheme and by adopting the maximal displacement increment (MDI). Through some verification examples, it is proved that the proposed method is correct and effective, and a higher computational efficiency is obtained.