为进一步提高有载分接开关(on-load tap changer,OLTC)机械状态监测的准确性,文中基于优化品质因数可调小波变换(tunable quality wavelet transform,TQWT)对OLTC切换过程中的振动信号进行了分析。即使用人工鱼群算法(artificial fish s...为进一步提高有载分接开关(on-load tap changer,OLTC)机械状态监测的准确性,文中基于优化品质因数可调小波变换(tunable quality wavelet transform,TQWT)对OLTC切换过程中的振动信号进行了分析。即使用人工鱼群算法(artificial fish swarm algorithm,AFSA)基于分解余量与整体正交系数研究了TQWT的优化分解方法,计算得到了OLTC振动信号的多个子序列,构建了基于优化孪生支持向量机(twin support vector machine,TWSVM)的OLTC机械故障诊断模型。对某CM型OLTC正常与典型机械故障下振动信号的分析结果表明,所提优化TQWT分解方法有效提高了OLTC振动信号分解结果的准确性。相对于其他诊断模型,所构建AFSA-TWSVM的OLTC机械故障诊断模型分类效果好且收敛速度更快。展开更多
对车联网中多个车辆用户设备(Vehicle User Equipment,VUE)卸载过程中的资源分配问题进行研究,提出一种时延感知的计算卸载和资源分配策略。采用支持向量机将卸载任务根据时延和能耗的要求选择移动边缘计算(Mobile Edge Computing,MEC)...对车联网中多个车辆用户设备(Vehicle User Equipment,VUE)卸载过程中的资源分配问题进行研究,提出一种时延感知的计算卸载和资源分配策略。采用支持向量机将卸载任务根据时延和能耗的要求选择移动边缘计算(Mobile Edge Computing,MEC)服务器辅助卸载和VUE辅助卸载两种处理模式,考虑MEC服务器的计算资源分配以及车到车链路复用蜂窝链路的干扰问题,建立最小化总成本的优化问题。最后,使用深度竞争双Q网络算法完成不同处理模式下相应的资源分配过程。为了验证所提策略的有效性,将其与基于深度Q网络算法的资源分配策略、基于正交多址接入的资源分配策略和随机资源分配策略等3种策略相比。验证结果表明,所提策略可以在最大时延限制内有效降低卸载总成本。展开更多
Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflict...Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflicting the Wenzhou region of Zhejiang province far away from the tropical storm center happening early on the morning of September 4, 1999 （TS9909 hereinafter）. Evidence suggests that, like previously-studied typhoons landing in autumn south of Xiamen to the eastern part of Guangdong, TS9909 has an inverted trough in the central south of the coastal belt of Zhejiang province that produces the rainstorm from the meso convective complex （MCC） on the warm, moist shear inside; the time and order of the magnitude of the rainfall are bound up with the development of the pattern of strong Q-vector divergence gradients during the event for the study area; the NE - SW coastline and the unique topography of the Yandang mountains inside the region are favorable for air lifting are the major contributors to the torrential rains.展开更多
文摘为进一步提高有载分接开关(on-load tap changer,OLTC)机械状态监测的准确性,文中基于优化品质因数可调小波变换(tunable quality wavelet transform,TQWT)对OLTC切换过程中的振动信号进行了分析。即使用人工鱼群算法(artificial fish swarm algorithm,AFSA)基于分解余量与整体正交系数研究了TQWT的优化分解方法,计算得到了OLTC振动信号的多个子序列,构建了基于优化孪生支持向量机(twin support vector machine,TWSVM)的OLTC机械故障诊断模型。对某CM型OLTC正常与典型机械故障下振动信号的分析结果表明,所提优化TQWT分解方法有效提高了OLTC振动信号分解结果的准确性。相对于其他诊断模型,所构建AFSA-TWSVM的OLTC机械故障诊断模型分类效果好且收敛速度更快。
文摘对车联网中多个车辆用户设备(Vehicle User Equipment,VUE)卸载过程中的资源分配问题进行研究,提出一种时延感知的计算卸载和资源分配策略。采用支持向量机将卸载任务根据时延和能耗的要求选择移动边缘计算(Mobile Edge Computing,MEC)服务器辅助卸载和VUE辅助卸载两种处理模式,考虑MEC服务器的计算资源分配以及车到车链路复用蜂窝链路的干扰问题,建立最小化总成本的优化问题。最后,使用深度竞争双Q网络算法完成不同处理模式下相应的资源分配过程。为了验证所提策略的有效性,将其与基于深度Q网络算法的资源分配策略、基于正交多址接入的资源分配策略和随机资源分配策略等3种策略相比。验证结果表明,所提策略可以在最大时延限制内有效降低卸载总成本。
基金sponsored jointly by the Natural Science Foundation of China (Grant 4040950009402050084)the Project of Planned National Key Basic Research/Development (2004CB418301)
文摘Using T106 numerical products, MM5 simulations in conjunction of Q-vector scheme-computed NCEP results, observations and satellite cloud images, study is undertaken for an exceptionally intense rainstorm event afflicting the Wenzhou region of Zhejiang province far away from the tropical storm center happening early on the morning of September 4, 1999 （TS9909 hereinafter）. Evidence suggests that, like previously-studied typhoons landing in autumn south of Xiamen to the eastern part of Guangdong, TS9909 has an inverted trough in the central south of the coastal belt of Zhejiang province that produces the rainstorm from the meso convective complex （MCC） on the warm, moist shear inside; the time and order of the magnitude of the rainfall are bound up with the development of the pattern of strong Q-vector divergence gradients during the event for the study area; the NE - SW coastline and the unique topography of the Yandang mountains inside the region are favorable for air lifting are the major contributors to the torrential rains.
