To provide a risk-sharing mechanism that encourages a component supplier and a manufacturer to expand their production capacity of components and products, many researches on SCM suggested that it is better for the SC...To provide a risk-sharing mechanism that encourages a component supplier and a manufacturer to expand their production capacity of components and products, many researches on SCM suggested that it is better for the SC players to connect a long-term contract with flexible preconditions before doing the decision-making of production capacity. With considering of the uncertainty of demand and integrity problems between SC players, it is difficult to set reasonable preconditions. As a result, under-investment problems still occur frequently. In this paper, after we had discussed the decision-making of production capacity with the preconditions by analyzing the character of the players, we verified the under-investment problem of the supply chain. In order to clarify the optimum preconditions to alleviate the under-investment problem, we also analyzed the relations between preconditions and supply capacity of the whole supply chain. In the last part of this paper, we proposed a method of preconditions setting in such uncertain situations.展开更多
The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,an...The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,and demand mismatch hinder their broader adoption.In response,shared energy storage systems(SESSs)offer a more cohesive and efficient use of ESS,providing more accessible and cost-effective energy storage solutions to overcome these obstacles.To enhance the profitability of SESSs,this paper designs a multi-time-scale resource allocation strategy based on long-term contracts and real-time rental business models.We initially construct a life cycle cost model for SESS and introduce a method to estimate the degradation costs of multiple battery groups by cycling numbers and depth of discharge within the SESS.Subsequently,we design various long-term contracts from both capacity and energy perspectives,establishing associated models and real-time rental models.Lastly,multi-time-scale resource allocation based on the decomposition of user demand is proposed.Numerical analysis validates that the business model based on long-term contracts excels over models operating solely in the real-time market in economic viability and user satisfaction,effectively reducing battery degradation,and leveraging the aggregation effect for SESS can generate an additional increase of 10.7%in net revenue.展开更多
在软件定义网络(Software Defined Networking,SDN)中,控制层很容易受到分布式拒绝服务(Distributed Denial of Service,DDoS)攻击的威胁。攻击者通过恶意请求或数据流等方式,向SDN控制器发送大量请求,从而使控制器资源耗尽,导致控制器...在软件定义网络(Software Defined Networking,SDN)中,控制层很容易受到分布式拒绝服务(Distributed Denial of Service,DDoS)攻击的威胁。攻击者通过恶意请求或数据流等方式,向SDN控制器发送大量请求,从而使控制器资源耗尽,导致控制器不能正常工作。因此,防范和处理控制层DDoS攻击是SDN安全的关键。该文提出一种基于区块链与排队理论的DDoS攻击检测防御机制,该防御机制结合区块链技术,设计了一种新的SDN架构模型,该模型对SDN控制层重新进行构造,在SDN控制层加入容量监控模块、安全模块及区块链模块。容量监控模块基于排队理论,计算进入控制器数据包队列的长度阈值,当队列内数据包数目连续2次超过阈值或控制器规则表容量达到70%容量触发报警,安全模块用于触发报警后在设置报警的数据包进行DDoS特征匹配,如果被确定为异常数据则将数据包摘要信息上传至区块链,利用智能合约共享异常数据包信息摘要,既能够防止过多的信息记录在区块链造成系统负载,又能够使SDN网络信息达成共识。对该攻击检测防御机制进行仿真实验,选出了效果最优参数,实验结果表明,与同类型系统相比,该机制对异常数据流的检测率及正常数据流的误报率均有所提升。展开更多
文摘To provide a risk-sharing mechanism that encourages a component supplier and a manufacturer to expand their production capacity of components and products, many researches on SCM suggested that it is better for the SC players to connect a long-term contract with flexible preconditions before doing the decision-making of production capacity. With considering of the uncertainty of demand and integrity problems between SC players, it is difficult to set reasonable preconditions. As a result, under-investment problems still occur frequently. In this paper, after we had discussed the decision-making of production capacity with the preconditions by analyzing the character of the players, we verified the under-investment problem of the supply chain. In order to clarify the optimum preconditions to alleviate the under-investment problem, we also analyzed the relations between preconditions and supply capacity of the whole supply chain. In the last part of this paper, we proposed a method of preconditions setting in such uncertain situations.
基金supported by National Natural Science Foundation of China(No.U2066601).
文摘The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,and demand mismatch hinder their broader adoption.In response,shared energy storage systems(SESSs)offer a more cohesive and efficient use of ESS,providing more accessible and cost-effective energy storage solutions to overcome these obstacles.To enhance the profitability of SESSs,this paper designs a multi-time-scale resource allocation strategy based on long-term contracts and real-time rental business models.We initially construct a life cycle cost model for SESS and introduce a method to estimate the degradation costs of multiple battery groups by cycling numbers and depth of discharge within the SESS.Subsequently,we design various long-term contracts from both capacity and energy perspectives,establishing associated models and real-time rental models.Lastly,multi-time-scale resource allocation based on the decomposition of user demand is proposed.Numerical analysis validates that the business model based on long-term contracts excels over models operating solely in the real-time market in economic viability and user satisfaction,effectively reducing battery degradation,and leveraging the aggregation effect for SESS can generate an additional increase of 10.7%in net revenue.
文摘在软件定义网络(Software Defined Networking,SDN)中,控制层很容易受到分布式拒绝服务(Distributed Denial of Service,DDoS)攻击的威胁。攻击者通过恶意请求或数据流等方式,向SDN控制器发送大量请求,从而使控制器资源耗尽,导致控制器不能正常工作。因此,防范和处理控制层DDoS攻击是SDN安全的关键。该文提出一种基于区块链与排队理论的DDoS攻击检测防御机制,该防御机制结合区块链技术,设计了一种新的SDN架构模型,该模型对SDN控制层重新进行构造,在SDN控制层加入容量监控模块、安全模块及区块链模块。容量监控模块基于排队理论,计算进入控制器数据包队列的长度阈值,当队列内数据包数目连续2次超过阈值或控制器规则表容量达到70%容量触发报警,安全模块用于触发报警后在设置报警的数据包进行DDoS特征匹配,如果被确定为异常数据则将数据包摘要信息上传至区块链,利用智能合约共享异常数据包信息摘要,既能够防止过多的信息记录在区块链造成系统负载,又能够使SDN网络信息达成共识。对该攻击检测防御机制进行仿真实验,选出了效果最优参数,实验结果表明,与同类型系统相比,该机制对异常数据流的检测率及正常数据流的误报率均有所提升。
