Multi-objective optimal evolutionary algorithms (MOEAs) are a kind of new effective algorithms to solve Multi-objective optimal problem (MOP). Because ranking, a method which is used by most MOEAs to solve MOP, has so...Multi-objective optimal evolutionary algorithms (MOEAs) are a kind of new effective algorithms to solve Multi-objective optimal problem (MOP). Because ranking, a method which is used by most MOEAs to solve MOP, has some shortcoming s, in this paper, we proposed a new method using tree structure to express the relationship of solutions. Experiments prove that the method can reach the Pare-to front, retain the diversity of the population, and use less time.展开更多
The constrained multi-objective multi-variable optimization of fans usually needs a great deal of computational fluid dynamics(CFD)calculations and is time-consuming.In this study,a new multi-model ensemble optimizati...The constrained multi-objective multi-variable optimization of fans usually needs a great deal of computational fluid dynamics(CFD)calculations and is time-consuming.In this study,a new multi-model ensemble optimization algorithm is proposed to tackle such an expensive optimization problem.The multi-variable and multi-objective optimization are conducted with a new flexible multi-objective infill criterion.In addition,the search direction is determined by the multi-model ensemble assisted evolutionary algorithm and the feature extraction by the principal component analysis is used to reduce the dimension of optimization variables.First,the proposed algorithm and other two optimization algorithms which prevail in fan optimizations were compared by using test functions.With the same number of objective function evaluations,the proposed algorithm shows a fast convergency rate on finding the optimal objective function values.Then,this algorithm was used to optimize the rotor and stator blades of a large axial fan,with the efficiencies as the objectives at three flow rates,the high,the design and the low flow rate.Forty-two variables were included in the optimization process.The results show that compared with the prototype fan,the total pressure efficiencies of the optimized fan at the high,the design and the low flow rate were increased by 3.35%,3.07%and 2.89%,respectively,after CFD simulations for 500 fan candidates with the constraint for the design pressure.The optimization results validate the effectiveness and feasibility of the proposed algorithm.展开更多
Today's volatile market conditions in electronic industries have lead to a new production system,seru(which is the Japanese pronunciation for cell),and has been widely implemented in hundreds of Japanese and other...Today's volatile market conditions in electronic industries have lead to a new production system,seru(which is the Japanese pronunciation for cell),and has been widely implemented in hundreds of Japanese and other Asia companies.In particular,the rotating seru has been widely implemented,where workers are fully cross-trained with the same skill level but may be different on the proficiency of performing tasks.The rotating seru production problem,which determines the rotating sequence of workers as well as the assembling sequence of jobs,is difficult to solve due to conflicting objectives and dynamic release of customer demands.To solve this problem,we propose a dynamic multiobjective NSGA-II based memetic algorithm.Moreover,to preserve desirable population diversity and improve the searching efficiency,we propose different problem-specific evolutionary strategies.Finally,we test the performance of our proposed memetic algorithm with other state-of-the-art multi-objective evolutionary algorithms and demonstrate the effectiveness of our proposed algorithm.展开更多
Conducting reasonable weapon-target assignment( WTA) with near real time can bring the maximum awards with minimum costs which are especially significant in the modern war. A framework of dynamic WTA( DWTA) model base...Conducting reasonable weapon-target assignment( WTA) with near real time can bring the maximum awards with minimum costs which are especially significant in the modern war. A framework of dynamic WTA( DWTA) model based on a series of staged static WTA( SWTA) models is established where dynamic factors including time window of target and time window of weapon are considered in the staged SWTA model. Then,a hybrid algorithm for the staged SWTA named Decomposition-Based Dynamic Weapon-target Assignment( DDWTA) is proposed which is based on the framework of multi-objective evolutionary algorithm based on decomposition( MOEA / D) with two major improvements: one is the coding based on constraint of resource to generate the feasible solutions, and the other is the tabu search strategy to speed up the convergence.Comparative experiments prove that the proposed algorithm is capable of obtaining a well-converged and well diversified set of solutions on a problem instance and meets the time demand in the battlefield environment.展开更多
Purpose–This is the first part of a two-part paper.The purpose of this paper is to report on methods that use the Response Surface Methodology(RSM)to investigate an Evolutionary Algorithm(EA)and memory-based approach...Purpose–This is the first part of a two-part paper.The purpose of this paper is to report on methods that use the Response Surface Methodology(RSM)to investigate an Evolutionary Algorithm(EA)and memory-based approach referred to as McBAR–the Mapping of Task IDs for Centroid-Based Adaptation with Random Immigrants.Some of the methods are useful for investigating the performance(solution-search abilities)of techniques(comprised of McBAR and other selected EAbased techniques)for solving some multi-objective dynamic resource-constrained project scheduling problems with time-varying number of tasks.Design/methodology/approach–The RSM is applied to:determine some EA parameters of the techniques,develop models of the performance of each technique,legitimize some algorithmic components of McBAR,manifest the relative performance of McBAR over the other techniques and determine the resiliency of McBAR against changes in the environment.Findings–The results of applying the methods are explored in the second part of this work.Originality/value–The models are composite and characterize an EA memory-based technique.Further,the resiliency of techniques is determined by applying Lagrange optimization that involves the models.展开更多
Purpose–This is the second part of a two-part paper.The purpose of this paper is to report the results on the application of the methods that use the Response Surface Methodology to investigate an evolutionary algori...Purpose–This is the second part of a two-part paper.The purpose of this paper is to report the results on the application of the methods that use the Response Surface Methodology to investigate an evolutionary algorithm(EA)and memory-based approach referred to as McBAR–the Mapping of Task IDs for Centroid-Based Adaptation with Random Immigrants.Design/methodology/approach–The methods applied in this paper are fully explained in the first part.They are utilized to investigate the performances(ability to determine solutions to problems)of techniques composed of McBAR and some EA-based techniques for solving some multi-objective dynamic resource-constrained project scheduling problems with a variable number of tasks.Findings–The main results include the following:first,some algorithmic components of McBAR are legitimate;second,the performance of McBAR is generally superior to those of the other techniques after increase in the number of tasks in each of the above-mentioned problems;and third,McBAR has the most resilient performance among the techniques against changes in the environment that set the problems.Originality/value–This paper is novel for investigating the enumerated results.展开更多
基金Supported by the National Natural Science Foundation of China(60073043,70071042,60133010)
文摘Multi-objective optimal evolutionary algorithms (MOEAs) are a kind of new effective algorithms to solve Multi-objective optimal problem (MOP). Because ranking, a method which is used by most MOEAs to solve MOP, has some shortcoming s, in this paper, we proposed a new method using tree structure to express the relationship of solutions. Experiments prove that the method can reach the Pare-to front, retain the diversity of the population, and use less time.
基金support of National Science and Technology Major Project(2017-11-0007-0021)。
文摘The constrained multi-objective multi-variable optimization of fans usually needs a great deal of computational fluid dynamics(CFD)calculations and is time-consuming.In this study,a new multi-model ensemble optimization algorithm is proposed to tackle such an expensive optimization problem.The multi-variable and multi-objective optimization are conducted with a new flexible multi-objective infill criterion.In addition,the search direction is determined by the multi-model ensemble assisted evolutionary algorithm and the feature extraction by the principal component analysis is used to reduce the dimension of optimization variables.First,the proposed algorithm and other two optimization algorithms which prevail in fan optimizations were compared by using test functions.With the same number of objective function evaluations,the proposed algorithm shows a fast convergency rate on finding the optimal objective function values.Then,this algorithm was used to optimize the rotor and stator blades of a large axial fan,with the efficiencies as the objectives at three flow rates,the high,the design and the low flow rate.Forty-two variables were included in the optimization process.The results show that compared with the prototype fan,the total pressure efficiencies of the optimized fan at the high,the design and the low flow rate were increased by 3.35%,3.07%and 2.89%,respectively,after CFD simulations for 500 fan candidates with the constraint for the design pressure.The optimization results validate the effectiveness and feasibility of the proposed algorithm.
基金We thank Professor Wei Jiang and two anonymous reviewers for their suggestions and comments.Feng Liu and Jiafu Tang were supported by the NSFC[grant numbers 71872033,71420107028]Kan Fang was supported by the NSFC[grant number 71701144]+1 种基金Yong Yin was supported by the Omron research fund.Feng Liu was also supported by the 2020 LiaoNing Revitalization Talents Program(XLYC2007061)the Dalian High Level Talents Innovation Support Plan(2019RQ107).
文摘Today's volatile market conditions in electronic industries have lead to a new production system,seru(which is the Japanese pronunciation for cell),and has been widely implemented in hundreds of Japanese and other Asia companies.In particular,the rotating seru has been widely implemented,where workers are fully cross-trained with the same skill level but may be different on the proficiency of performing tasks.The rotating seru production problem,which determines the rotating sequence of workers as well as the assembling sequence of jobs,is difficult to solve due to conflicting objectives and dynamic release of customer demands.To solve this problem,we propose a dynamic multiobjective NSGA-II based memetic algorithm.Moreover,to preserve desirable population diversity and improve the searching efficiency,we propose different problem-specific evolutionary strategies.Finally,we test the performance of our proposed memetic algorithm with other state-of-the-art multi-objective evolutionary algorithms and demonstrate the effectiveness of our proposed algorithm.
文摘Conducting reasonable weapon-target assignment( WTA) with near real time can bring the maximum awards with minimum costs which are especially significant in the modern war. A framework of dynamic WTA( DWTA) model based on a series of staged static WTA( SWTA) models is established where dynamic factors including time window of target and time window of weapon are considered in the staged SWTA model. Then,a hybrid algorithm for the staged SWTA named Decomposition-Based Dynamic Weapon-target Assignment( DDWTA) is proposed which is based on the framework of multi-objective evolutionary algorithm based on decomposition( MOEA / D) with two major improvements: one is the coding based on constraint of resource to generate the feasible solutions, and the other is the tabu search strategy to speed up the convergence.Comparative experiments prove that the proposed algorithm is capable of obtaining a well-converged and well diversified set of solutions on a problem instance and meets the time demand in the battlefield environment.
文摘Purpose–This is the first part of a two-part paper.The purpose of this paper is to report on methods that use the Response Surface Methodology(RSM)to investigate an Evolutionary Algorithm(EA)and memory-based approach referred to as McBAR–the Mapping of Task IDs for Centroid-Based Adaptation with Random Immigrants.Some of the methods are useful for investigating the performance(solution-search abilities)of techniques(comprised of McBAR and other selected EAbased techniques)for solving some multi-objective dynamic resource-constrained project scheduling problems with time-varying number of tasks.Design/methodology/approach–The RSM is applied to:determine some EA parameters of the techniques,develop models of the performance of each technique,legitimize some algorithmic components of McBAR,manifest the relative performance of McBAR over the other techniques and determine the resiliency of McBAR against changes in the environment.Findings–The results of applying the methods are explored in the second part of this work.Originality/value–The models are composite and characterize an EA memory-based technique.Further,the resiliency of techniques is determined by applying Lagrange optimization that involves the models.
文摘Purpose–This is the second part of a two-part paper.The purpose of this paper is to report the results on the application of the methods that use the Response Surface Methodology to investigate an evolutionary algorithm(EA)and memory-based approach referred to as McBAR–the Mapping of Task IDs for Centroid-Based Adaptation with Random Immigrants.Design/methodology/approach–The methods applied in this paper are fully explained in the first part.They are utilized to investigate the performances(ability to determine solutions to problems)of techniques composed of McBAR and some EA-based techniques for solving some multi-objective dynamic resource-constrained project scheduling problems with a variable number of tasks.Findings–The main results include the following:first,some algorithmic components of McBAR are legitimate;second,the performance of McBAR is generally superior to those of the other techniques after increase in the number of tasks in each of the above-mentioned problems;and third,McBAR has the most resilient performance among the techniques against changes in the environment that set the problems.Originality/value–This paper is novel for investigating the enumerated results.