In the manufacturing industry,reasonable scheduling can greatly improve production efficiency,while excessive resource consumption highlights the growing significance of energy conservation in production.This paper st...In the manufacturing industry,reasonable scheduling can greatly improve production efficiency,while excessive resource consumption highlights the growing significance of energy conservation in production.This paper studies the problem of energy-efficient distributed heterogeneous permutation flowshop problem with variable processing speed(DHPFSP-VPS),considering both the minimum makespan and total energy consumption(TEC)as objectives.A discrete multi-objective squirrel search algorithm(DMSSA)is proposed to solve the DHPFSPVPS.DMSSA makes four improvements based on the squirrel search algorithm.Firstly,in terms of the population initialization strategy,four hybrid initialization methods targeting different objectives are proposed to enhance the quality of initial solutions.Secondly,enhancements are made to the population hierarchy system and position updating methods of the squirrel search algorithm,making it more suitable for discrete scheduling problems.Additionally,regarding the search strategy,six local searches are designed based on problem characteristics to enhance search capability.Moreover,a dynamic predator strategy based on Q-learning is devised to effectively balance DMSSA’s capability for global exploration and local exploitation.Finally,two speed control energy-efficient strategies are designed to reduce TEC.Extensive comparative experiments are conducted in this paper to validate the effectiveness of the proposed strategies.The results of comparing DMSSA with other algorithms demonstrate its superior performance and its potential for efficient solving of the DHPFSP-VPS problem.展开更多
In this research,a novel dynamic and heterogeneous identity based cooperative co-evolutionary algorithm(DHICCA)is proposed for addressing the distributed lot-streaming flowshop scheduling problem(DLSFSP)with the objec...In this research,a novel dynamic and heterogeneous identity based cooperative co-evolutionary algorithm(DHICCA)is proposed for addressing the distributed lot-streaming flowshop scheduling problem(DLSFSP)with the objective to minimize the makespan.A two-layer-vector representation is devised to bridge the solution space of DLSFSP and the search space of DHICCA.In the evolution of DHICCA,population individuals are endowed with heterogeneous identities according to their quality,including superior individuals,ordinary individuals,and inferior individuals,which serve local exploitation,global exploration,and diversified restart,respectively.Because individuals with different identities require different evolutionary mechanisms to fully unleash their respective potentials,identity-specific evolutionary operators are devised to evolve them in a cooperative co-evolutionary way.This is important to use limited population resources to solve complex optimization problems.Specifically,exploitation is carried out on superior individuals by devising three exploitative operators with different intensities based on techniques of variable neighborhood,destruction-construction,and gene targeting.Exploration is executed on ordinary individuals by a newly constructed discrete Jaya algorithm and a probability crossover strategy.In addition,restart is performed on inferior individuals to introduce new evolutionary individuals to the population.After the cooperative co-evolution,all individuals with different identities are merged as a population again,and their identities are dynamically adjusted by new evaluation.The influence of parameters on the algorithm is investigated based on design-of-experiment and comprehensive computational experiments are used to evaluate the performance of all algorithms.The results validate the effectiveness of special designs and show that DHICCA performs more efficient than the existing state-of-the-art algorithms in solving the DLSFSP.展开更多
The distributed permutation flowshop scheduling problem(DPFSP)has received increasing attention in recent years,which always assumes that the machine can process without restrictions.However,in practical production,ma...The distributed permutation flowshop scheduling problem(DPFSP)has received increasing attention in recent years,which always assumes that the machine can process without restrictions.However,in practical production,machine preventive maintenance is required to prevent machine breakdowns.Therefore,this paper studies the DPFSP with preventive maintenance(PM/DPFSP)aiming at minimizing the total flowtime.For solving the problem,a discrete gray wolf optimization algorithm with restart mechanism(DGWO_RM)is proposed.In the initialization phase,a heuristic algorithm that takes into consideration preventive maintenance and idle time is employed to elevate the quality of the initial solution.Next,four local search strategies are proposed for further enhancing the exploitation capability.Furthermore,a restart mechanism is integrated into algorithm to avert the risk of converging prematurely to a suboptimal solution,thereby ensuring a broader exploration of potential solutions.Finally,comprehensive experiments studies are carried out to illustrate the effectiveness of the proposed strategy and to verify the performance of DGWO_RM.The obtained results show that the proposed DGWO_RM significantly outperforms the four state-of-the-art algorithms in solving PM/DPFSP.展开更多
基金supported by the Key Research and Development Project of Hubei Province(Nos.2020BAB114 and 2023BAB094).
文摘In the manufacturing industry,reasonable scheduling can greatly improve production efficiency,while excessive resource consumption highlights the growing significance of energy conservation in production.This paper studies the problem of energy-efficient distributed heterogeneous permutation flowshop problem with variable processing speed(DHPFSP-VPS),considering both the minimum makespan and total energy consumption(TEC)as objectives.A discrete multi-objective squirrel search algorithm(DMSSA)is proposed to solve the DHPFSPVPS.DMSSA makes four improvements based on the squirrel search algorithm.Firstly,in terms of the population initialization strategy,four hybrid initialization methods targeting different objectives are proposed to enhance the quality of initial solutions.Secondly,enhancements are made to the population hierarchy system and position updating methods of the squirrel search algorithm,making it more suitable for discrete scheduling problems.Additionally,regarding the search strategy,six local searches are designed based on problem characteristics to enhance search capability.Moreover,a dynamic predator strategy based on Q-learning is devised to effectively balance DMSSA’s capability for global exploration and local exploitation.Finally,two speed control energy-efficient strategies are designed to reduce TEC.Extensive comparative experiments are conducted in this paper to validate the effectiveness of the proposed strategies.The results of comparing DMSSA with other algorithms demonstrate its superior performance and its potential for efficient solving of the DHPFSP-VPS problem.
基金supported by the National Natural Science Foundation of China(No.62003258)Natural Science Foundation of Hebei Province(No.F2024204007)Projection of State Key Laboratory for Manufacturing Systems Engineering of Xi’an Jiaotong University(No.sklms 2023002).
文摘In this research,a novel dynamic and heterogeneous identity based cooperative co-evolutionary algorithm(DHICCA)is proposed for addressing the distributed lot-streaming flowshop scheduling problem(DLSFSP)with the objective to minimize the makespan.A two-layer-vector representation is devised to bridge the solution space of DLSFSP and the search space of DHICCA.In the evolution of DHICCA,population individuals are endowed with heterogeneous identities according to their quality,including superior individuals,ordinary individuals,and inferior individuals,which serve local exploitation,global exploration,and diversified restart,respectively.Because individuals with different identities require different evolutionary mechanisms to fully unleash their respective potentials,identity-specific evolutionary operators are devised to evolve them in a cooperative co-evolutionary way.This is important to use limited population resources to solve complex optimization problems.Specifically,exploitation is carried out on superior individuals by devising three exploitative operators with different intensities based on techniques of variable neighborhood,destruction-construction,and gene targeting.Exploration is executed on ordinary individuals by a newly constructed discrete Jaya algorithm and a probability crossover strategy.In addition,restart is performed on inferior individuals to introduce new evolutionary individuals to the population.After the cooperative co-evolution,all individuals with different identities are merged as a population again,and their identities are dynamically adjusted by new evaluation.The influence of parameters on the algorithm is investigated based on design-of-experiment and comprehensive computational experiments are used to evaluate the performance of all algorithms.The results validate the effectiveness of special designs and show that DHICCA performs more efficient than the existing state-of-the-art algorithms in solving the DLSFSP.
基金supported by the National Natural Science Foundation of China(Nos.62473186 and 62273221)Natural Science Foundation of Shandong Province(No.ZR2024MF017)Discipline with Strong Characteristics of Liaocheng University Intelligent Science and Technology(No.319462208).
文摘The distributed permutation flowshop scheduling problem(DPFSP)has received increasing attention in recent years,which always assumes that the machine can process without restrictions.However,in practical production,machine preventive maintenance is required to prevent machine breakdowns.Therefore,this paper studies the DPFSP with preventive maintenance(PM/DPFSP)aiming at minimizing the total flowtime.For solving the problem,a discrete gray wolf optimization algorithm with restart mechanism(DGWO_RM)is proposed.In the initialization phase,a heuristic algorithm that takes into consideration preventive maintenance and idle time is employed to elevate the quality of the initial solution.Next,four local search strategies are proposed for further enhancing the exploitation capability.Furthermore,a restart mechanism is integrated into algorithm to avert the risk of converging prematurely to a suboptimal solution,thereby ensuring a broader exploration of potential solutions.Finally,comprehensive experiments studies are carried out to illustrate the effectiveness of the proposed strategy and to verify the performance of DGWO_RM.The obtained results show that the proposed DGWO_RM significantly outperforms the four state-of-the-art algorithms in solving PM/DPFSP.
