In the tide of knowledge economy, the supply chain is facing the diversified customs' preference and the uncertain market demand. Core companies should encourage the staff of knowledge innovation and apply scientific...In the tide of knowledge economy, the supply chain is facing the diversified customs' preference and the uncertain market demand. Core companies should encourage the staff of knowledge innovation and apply scientific means to forecast extemal conditions reasonably for response market test rapidly. Through the analysis of the problems existing in the flexible management, they would make corresponding measures to solve those problems to improve enterprise performance.展开更多
In supply chain management,an important research direction is to coordinate the supply chain through introducing flexible contracts.A supply chain contract is flexible if it can satisfy two conditions at the same time...In supply chain management,an important research direction is to coordinate the supply chain through introducing flexible contracts.A supply chain contract is flexible if it can satisfy two conditions at the same time:the supply chain is coordinated,and the total profit of the supply chain can be arbitrarily divided between the supply chain members.This paper puts out two contracts,a flexible return contract and a flexible wholesale price discount contract.In contrast to many of literature,the supply chain contracts with an endogenous wholesale price is specifically considered,and a detailed sensitivity analysis of the contract parameters is given.The paper also discusses the application of the contract in vendor-managed inventory(VMI) mode.The results show that the supply chain's performance is improved after introducing above contracts.All the findings are illustrated by numerical examples.展开更多
A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to...A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to poor performance.The method combines a fault-tolerant fault location method based on long-term and short-term memory networks to accurately locate the fault section.Then,an operation control method for relay protection based on adaptive weight and whale optimization algorithm(WOA)is used to construct an objective function considering the shortest relay protection action time and the smallest impulse current.The adaptive weight and WOA are employed to obtain the optimal strategy for relay protection operation control,reducing the action time and impulse current.Experimental results demonstrate the effectiveness of the proposed method in accurately locating faults and improving relay protection performance.The longest operation time is reduced by 4.7023 s,and the maximum impulse current is limited to 0.3 A,effectively controlling the impact of large impulse currents and enhancing control efficiency.展开更多
With the vehement development of global competition , Agile Supply Chain (ASC) becomes an effective approach that supports dynamic ent erprise alliance and realizes agile manufacturing, as for the enterprises to cap t...With the vehement development of global competition , Agile Supply Chain (ASC) becomes an effective approach that supports dynamic ent erprise alliance and realizes agile manufacturing, as for the enterprises to cap ture market opportunities rapidly and strengthen their anti-risk ability. As Ag ile Supply Chain System (ASCS) is dynamic and distributed, the realization of it ’s processes needs to be much flexible. Often in Agile Supply Chain System (ASCS ), there are many dynamic tasks, many changes of the processes, and cooperative workflows, which need the workflows able to be adjusted agilely and smoothly, no t much affecting others. This paper will propose a flexible workflow management for achieving the agility and compatibility. At the first of the paper, we will discuss the situation in which Agile Supply C hain System is applied, and then we will elaborate the characteristics of Agile Supply Chain System. So with that, the shortcomings of the process managements t hat are, at present, used in Supply Chain Systems will be displayed clearly. The n, the proposal will be given in the paper, to resolve the problems in the prese nt process management in ASCS. We will see supply chain systems implemented mult i-agent-based technology to adapt to the dynamic environment, however in many systems, coordination of the workflows is executed by the explicit messages comm unicated between the agents. This will lead to a tightly coupled system. To over come it, the paper suggests the workflow management in agent-based ASCS using t he Events-Triggering mechanism, instead of the explicit messages. We create Eve nts-Triggering contents and rules, having push-pull mechanism, event-state se t and triggering-conditions, and store them in the distributed database subject ed to the corresponding agents. Adjusting the Events-Triggering data will be us ed to adapt to the dynamic tasks and the changes of processes. In sum, we will p resent the methods of process modeling, the system structure, and the executing -mechanism of the flexible workflow management we propose in the paper. Also, t he paper outlines several exception-handling policies for the flexible workflow management, in succession. And at the final of the paper, we discuss the realiz ation of the flexible workflow management in Agile Supply Chain System. The flex ible workflow management will be implemented using CORBA services and Java techn ology for the distributed systems. CORBA is chosen as the specification of distr ibuted electronic data exchange, and Java as the construction tool of the system . The framework of the flexible workflow management constructed on them is showe d in the paper.展开更多
随着可再生能源渗透率的提升,其不确定性给综合能源系统(integrated energy system,IES)的经济性和鲁棒性带来了极大挑战。为了促进可再生能源消纳以及降低碳排放量,提出了一种基于数据驱动的分布鲁棒优化(distributionally robust opti...随着可再生能源渗透率的提升,其不确定性给综合能源系统(integrated energy system,IES)的经济性和鲁棒性带来了极大挑战。为了促进可再生能源消纳以及降低碳排放量,提出了一种基于数据驱动的分布鲁棒优化(distributionally robust optimization,DRO)调度策略。首先,构建了由有机朗肯循环(organic Rankine cycle,ORC)、氢燃料电池和电动汽车等构成的供需灵活响应模型,并引入阶梯碳交易机制来约束系统碳排放量。其次,为了能获取最恶劣情况下的场景概率分布,采用综合范数对风电输出场景的概率分布置信集合进行约束。然后,以在最恶劣场景概率分布下综合能源系统运行总成本最低为目标建立两阶段鲁棒优化模型,并通过列和约束生成(column and constraint generation,CCG)算法对模型进行迭代求解。最后,算例仿真结果表明了所提模型和求解方法的有效性,并分析了阶梯碳交易机制和供需灵活响应模型对提高系统灵活性和低碳经济性的影响。展开更多
构建具有可靠供电能力的低压配电网具有重要意义,然而低压配电网供电能力受到低压配电变压器负载、低压配电网新能源消纳能力以及低压配电网供电电压3大要素影响。因此,该文基于低压配电网柔性互联技术提出考虑供电能力提升的低压配电...构建具有可靠供电能力的低压配电网具有重要意义,然而低压配电网供电能力受到低压配电变压器负载、低压配电网新能源消纳能力以及低压配电网供电电压3大要素影响。因此,该文基于低压配电网柔性互联技术提出考虑供电能力提升的低压配电网柔性互联规划方法,通过抽取影响低压配电网供电能力的主要场景建立低压配电网柔性互联规划框架。另外,针对该文多主体规划运行模型的不确定性,采用信息间隙决策理论(information gap decision theory,IGDT)与基于Wasserstein距离的分布鲁棒方法进行精细化建模。最后,采用MATLAB和CPLEX求解器在IEEE 38节点配电网上进行算例分析。仿真结果表明,该规划方法在有效提升低压配电网供电能力的同时具有更好的经济性。展开更多
Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified ...Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy.展开更多
文摘In the tide of knowledge economy, the supply chain is facing the diversified customs' preference and the uncertain market demand. Core companies should encourage the staff of knowledge innovation and apply scientific means to forecast extemal conditions reasonably for response market test rapidly. Through the analysis of the problems existing in the flexible management, they would make corresponding measures to solve those problems to improve enterprise performance.
基金supported by the Science and Technology Project of Zhejiang Province (2009C110262009C35007)
文摘In supply chain management,an important research direction is to coordinate the supply chain through introducing flexible contracts.A supply chain contract is flexible if it can satisfy two conditions at the same time:the supply chain is coordinated,and the total profit of the supply chain can be arbitrarily divided between the supply chain members.This paper puts out two contracts,a flexible return contract and a flexible wholesale price discount contract.In contrast to many of literature,the supply chain contracts with an endogenous wholesale price is specifically considered,and a detailed sensitivity analysis of the contract parameters is given.The paper also discusses the application of the contract in vendor-managed inventory(VMI) mode.The results show that the supply chain's performance is improved after introducing above contracts.All the findings are illustrated by numerical examples.
文摘A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to poor performance.The method combines a fault-tolerant fault location method based on long-term and short-term memory networks to accurately locate the fault section.Then,an operation control method for relay protection based on adaptive weight and whale optimization algorithm(WOA)is used to construct an objective function considering the shortest relay protection action time and the smallest impulse current.The adaptive weight and WOA are employed to obtain the optimal strategy for relay protection operation control,reducing the action time and impulse current.Experimental results demonstrate the effectiveness of the proposed method in accurately locating faults and improving relay protection performance.The longest operation time is reduced by 4.7023 s,and the maximum impulse current is limited to 0.3 A,effectively controlling the impact of large impulse currents and enhancing control efficiency.
文摘With the vehement development of global competition , Agile Supply Chain (ASC) becomes an effective approach that supports dynamic ent erprise alliance and realizes agile manufacturing, as for the enterprises to cap ture market opportunities rapidly and strengthen their anti-risk ability. As Ag ile Supply Chain System (ASCS) is dynamic and distributed, the realization of it ’s processes needs to be much flexible. Often in Agile Supply Chain System (ASCS ), there are many dynamic tasks, many changes of the processes, and cooperative workflows, which need the workflows able to be adjusted agilely and smoothly, no t much affecting others. This paper will propose a flexible workflow management for achieving the agility and compatibility. At the first of the paper, we will discuss the situation in which Agile Supply C hain System is applied, and then we will elaborate the characteristics of Agile Supply Chain System. So with that, the shortcomings of the process managements t hat are, at present, used in Supply Chain Systems will be displayed clearly. The n, the proposal will be given in the paper, to resolve the problems in the prese nt process management in ASCS. We will see supply chain systems implemented mult i-agent-based technology to adapt to the dynamic environment, however in many systems, coordination of the workflows is executed by the explicit messages comm unicated between the agents. This will lead to a tightly coupled system. To over come it, the paper suggests the workflow management in agent-based ASCS using t he Events-Triggering mechanism, instead of the explicit messages. We create Eve nts-Triggering contents and rules, having push-pull mechanism, event-state se t and triggering-conditions, and store them in the distributed database subject ed to the corresponding agents. Adjusting the Events-Triggering data will be us ed to adapt to the dynamic tasks and the changes of processes. In sum, we will p resent the methods of process modeling, the system structure, and the executing -mechanism of the flexible workflow management we propose in the paper. Also, t he paper outlines several exception-handling policies for the flexible workflow management, in succession. And at the final of the paper, we discuss the realiz ation of the flexible workflow management in Agile Supply Chain System. The flex ible workflow management will be implemented using CORBA services and Java techn ology for the distributed systems. CORBA is chosen as the specification of distr ibuted electronic data exchange, and Java as the construction tool of the system . The framework of the flexible workflow management constructed on them is showe d in the paper.
文摘随着可再生能源渗透率的提升,其不确定性给综合能源系统(integrated energy system,IES)的经济性和鲁棒性带来了极大挑战。为了促进可再生能源消纳以及降低碳排放量,提出了一种基于数据驱动的分布鲁棒优化(distributionally robust optimization,DRO)调度策略。首先,构建了由有机朗肯循环(organic Rankine cycle,ORC)、氢燃料电池和电动汽车等构成的供需灵活响应模型,并引入阶梯碳交易机制来约束系统碳排放量。其次,为了能获取最恶劣情况下的场景概率分布,采用综合范数对风电输出场景的概率分布置信集合进行约束。然后,以在最恶劣场景概率分布下综合能源系统运行总成本最低为目标建立两阶段鲁棒优化模型,并通过列和约束生成(column and constraint generation,CCG)算法对模型进行迭代求解。最后,算例仿真结果表明了所提模型和求解方法的有效性,并分析了阶梯碳交易机制和供需灵活响应模型对提高系统灵活性和低碳经济性的影响。
文摘构建具有可靠供电能力的低压配电网具有重要意义,然而低压配电网供电能力受到低压配电变压器负载、低压配电网新能源消纳能力以及低压配电网供电电压3大要素影响。因此,该文基于低压配电网柔性互联技术提出考虑供电能力提升的低压配电网柔性互联规划方法,通过抽取影响低压配电网供电能力的主要场景建立低压配电网柔性互联规划框架。另外,针对该文多主体规划运行模型的不确定性,采用信息间隙决策理论(information gap decision theory,IGDT)与基于Wasserstein距离的分布鲁棒方法进行精细化建模。最后,采用MATLAB和CPLEX求解器在IEEE 38节点配电网上进行算例分析。仿真结果表明,该规划方法在有效提升低压配电网供电能力的同时具有更好的经济性。
基金supported in part by the Scientific Foundation for Outstanding Young Scientists of Sichuan under Grant No.2021JDJQ0032in part by the National Natural Science Foundation of China under Grant No.52107128in part by the Natural Science Foundation of Sichuan Province under Grant No.2022NSFSC0436.
文摘Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy.