无线供能及移动边缘计算技术的整合为下一代无线通信网的实现提供了技术支持。然而,用户数量的激增将对诸如系统响应时效性和超低延时等需求的实现提出了新的挑战。因此,如何设计迭代次数少、收敛速度快、灵活性强的实时计算卸载策略成...无线供能及移动边缘计算技术的整合为下一代无线通信网的实现提供了技术支持。然而,用户数量的激增将对诸如系统响应时效性和超低延时等需求的实现提出了新的挑战。因此,如何设计迭代次数少、收敛速度快、灵活性强的实时计算卸载策略成了研究的新热点。文章梳理了无线供能移动边缘计算(Wireless Powered Mobile Edge Computing,WP-MEC)系统在实现超低延时需求上面临的问题与挑战;总结了WP-MEC系统的网络模型及其计算卸载策略的研究概况;详细阐述了4种不同接入方式下的WP-MEC系统的计算卸载策略研究现状;对比分析了各类传统的数值优化方法及深度强化学习优化方法在实时计算卸载决策方面的优劣;对低复杂度高效计算卸载策略的发展进行总结与展望,提出了延时最小化计算卸载策略的3个关键研究方向。展开更多
The possibility of the electric-hydraulic chattering technology and its application in the cold extrusion were presented.The conventional and electric-hydraulic chattering assisted backward extrusion processes were pe...The possibility of the electric-hydraulic chattering technology and its application in the cold extrusion were presented.The conventional and electric-hydraulic chattering assisted backward extrusion processes were performed on 6061 aluminum alloy billets at room temperature.The experimental results showed that 5.65% reduction in the extrusion load was attained if the die and ejector were vibrated at a frequency of 100 Hz and amplitude of 0.013 mm in the longitudinal direction.The friction coefficient at the billet and tool system interface determined from the finite element analysis（FEA） decreased from 0.2 without chattering to 0.1 with application of electric-hydraulic chattering.The higher values of instantaneous velocity and direction change of material flow were achieved during the chattering assisted backward extrusion process.The strain distribution of the chattering assisted backward extrusion billet revealed lower maximum strain and smoother strain distribution in comparison with that produced by the conventional extrusion method.展开更多
文摘无线供能及移动边缘计算技术的整合为下一代无线通信网的实现提供了技术支持。然而,用户数量的激增将对诸如系统响应时效性和超低延时等需求的实现提出了新的挑战。因此,如何设计迭代次数少、收敛速度快、灵活性强的实时计算卸载策略成了研究的新热点。文章梳理了无线供能移动边缘计算(Wireless Powered Mobile Edge Computing,WP-MEC)系统在实现超低延时需求上面临的问题与挑战;总结了WP-MEC系统的网络模型及其计算卸载策略的研究概况;详细阐述了4种不同接入方式下的WP-MEC系统的计算卸载策略研究现状;对比分析了各类传统的数值优化方法及深度强化学习优化方法在实时计算卸载决策方面的优劣;对低复杂度高效计算卸载策略的发展进行总结与展望,提出了延时最小化计算卸载策略的3个关键研究方向。
基金Project(51275475)supported by the National Natural Science Foundation of ChinaProject(2014BY001)supported by the Department of Education in Zhejiang Province,ChinaProject(2014EP0110)supported by the Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology,Ministry of Education and Zhejiang Province,China
文摘The possibility of the electric-hydraulic chattering technology and its application in the cold extrusion were presented.The conventional and electric-hydraulic chattering assisted backward extrusion processes were performed on 6061 aluminum alloy billets at room temperature.The experimental results showed that 5.65% reduction in the extrusion load was attained if the die and ejector were vibrated at a frequency of 100 Hz and amplitude of 0.013 mm in the longitudinal direction.The friction coefficient at the billet and tool system interface determined from the finite element analysis（FEA） decreased from 0.2 without chattering to 0.1 with application of electric-hydraulic chattering.The higher values of instantaneous velocity and direction change of material flow were achieved during the chattering assisted backward extrusion process.The strain distribution of the chattering assisted backward extrusion billet revealed lower maximum strain and smoother strain distribution in comparison with that produced by the conventional extrusion method.
