Evolutionary algorithm is applied for distillation separation sequence optimization synthesis problems with combination explosion. The binary tree data structure is used to describe the distillation separation sequenc...Evolutionary algorithm is applied for distillation separation sequence optimization synthesis problems with combination explosion. The binary tree data structure is used to describe the distillation separation sequence, and it is directly applied as the coding method. Genetic operators, which ensure to prohibit illegal filial generations completely, are designed by using the method of graph theory. The crossover operator based on a single parent or two parents is designed successfully. The example shows that the average ratio of search space from evolutionary algorithm with two-parent genetic operation is lower, whereas the rate of successful minimizations from evolutionary algorithm with single parent genetic operation is higher.展开更多
Based on stochastic optimization strategy, a formulation methodology is proposed for synthesizing distillation column sequences, allowing more than one middle component as the distributing components between a pair of...Based on stochastic optimization strategy, a formulation methodology is proposed for synthesizing distillation column sequences, allowing more than one middle component as the distributing components between a pair of key components in the non-sharp split. In order to represent and manipulate the distillation configuration structures, a new coding procedure is proposed in the form of one-dimensional array. Theoretically, an array can represent any kind of split(non-sharp and sharp). With the application of a binary sort tree approach, a robust flow sheet encoding and decoding procedure is developed so that the problem formulation and solution becomes tractable. In this paper,the synthesis problem is formulated as a mixed-integer nonlinear programming(MINLP) problem and an improved simulated annealing approach is adopted to solve the optimization problem. Besides, a shortcut method is applied to the evaluation of all required design parameters as well as the total function.展开更多
A new method for the fast detection and evaluation of optimization potentials for separation processes is presented within this work. The method disclaims the application of difficult rigorous mathematical optimizatio...A new method for the fast detection and evaluation of optimization potentials for separation processes is presented within this work. The method disclaims the application of difficult rigorous mathematical optimization techniques by a number of different smart workarounds. The basis for the optimization is the application of different heuristics, shortcut methods and simulation studies. The method was applied to a real process in which the overall yield was improved of about 58%. Due to the new configuration an alternative control scheme containing unusual control loops was implemented.展开更多
The aim of this paper is to consider the following two problems:(1) Establish interrelationships between the growth of coefficients and the geometric distribution of zeros of solutions of non-homogeneous linear differ...The aim of this paper is to consider the following two problems:(1) Establish interrelationships between the growth of coefficients and the geometric distribution of zeros of solutions of non-homogeneous linear differential equation f′"+A_2(z)f"+A_1(z)f′+A_0(z)f=A_3(z)where A(z),..., A(z) are analytic functions in the unit disc D;(2) Find some sufficient conditions on the analytic coefficients of the differential equation for all solutions to belong to the Zygmund type space.The f^{(k)}+A_{k-1}(z)f^{(k-1)}+\cdots+A_1(z)f'+A_0(z)f=0 results we obtain are a generalization of some earlier results by Heittokangas, Gröhn,Korhoneon and Rättyä.展开更多
文摘Evolutionary algorithm is applied for distillation separation sequence optimization synthesis problems with combination explosion. The binary tree data structure is used to describe the distillation separation sequence, and it is directly applied as the coding method. Genetic operators, which ensure to prohibit illegal filial generations completely, are designed by using the method of graph theory. The crossover operator based on a single parent or two parents is designed successfully. The example shows that the average ratio of search space from evolutionary algorithm with two-parent genetic operation is lower, whereas the rate of successful minimizations from evolutionary algorithm with single parent genetic operation is higher.
基金Supported by the 973 Program of China(2012CB720503)the Open Research Project of State Kay Laboratory of Chemical Engineering(SKL-Ch E-13B02)
文摘Based on stochastic optimization strategy, a formulation methodology is proposed for synthesizing distillation column sequences, allowing more than one middle component as the distributing components between a pair of key components in the non-sharp split. In order to represent and manipulate the distillation configuration structures, a new coding procedure is proposed in the form of one-dimensional array. Theoretically, an array can represent any kind of split(non-sharp and sharp). With the application of a binary sort tree approach, a robust flow sheet encoding and decoding procedure is developed so that the problem formulation and solution becomes tractable. In this paper,the synthesis problem is formulated as a mixed-integer nonlinear programming(MINLP) problem and an improved simulated annealing approach is adopted to solve the optimization problem. Besides, a shortcut method is applied to the evaluation of all required design parameters as well as the total function.
文摘A new method for the fast detection and evaluation of optimization potentials for separation processes is presented within this work. The method disclaims the application of difficult rigorous mathematical optimization techniques by a number of different smart workarounds. The basis for the optimization is the application of different heuristics, shortcut methods and simulation studies. The method was applied to a real process in which the overall yield was improved of about 58%. Due to the new configuration an alternative control scheme containing unusual control loops was implemented.
基金National Natural Science Foundation of China(Grant No.11661043)。
文摘The aim of this paper is to consider the following two problems:(1) Establish interrelationships between the growth of coefficients and the geometric distribution of zeros of solutions of non-homogeneous linear differential equation f′"+A_2(z)f"+A_1(z)f′+A_0(z)f=A_3(z)where A(z),..., A(z) are analytic functions in the unit disc D;(2) Find some sufficient conditions on the analytic coefficients of the differential equation for all solutions to belong to the Zygmund type space.The f^{(k)}+A_{k-1}(z)f^{(k-1)}+\cdots+A_1(z)f'+A_0(z)f=0 results we obtain are a generalization of some earlier results by Heittokangas, Gröhn,Korhoneon and Rättyä.
