农机轨迹行为模式识别是一项多变量时间序列分类(multivariate time series classification,MTSC)任务,旨在提取农机轨迹数据中蕴藏的时空特征来识别农机轨迹行为模式,并为每个轨迹点分配相应的语义标签。针对现有方法对轨迹时空信息捕...农机轨迹行为模式识别是一项多变量时间序列分类(multivariate time series classification,MTSC)任务,旨在提取农机轨迹数据中蕴藏的时空特征来识别农机轨迹行为模式,并为每个轨迹点分配相应的语义标签。针对现有方法对轨迹时空信息捕捉能力不足和识别精度不佳的问题,提出了多维时空交互网络(multidimensional spatio-temporal interaction network,MSINet)来识别农机轨迹的行为模式。提出了多维信息交互(multidimensional infor-mation interaction,MII)模块,其融合了图卷积与自注意力机制以捕捉轨迹点之间的局部关联与全局依赖,同时利用双向感知机制实现通道与空间维度的信息互补;设计了多路径特征提取(multipath feature extraction,MFE)模块,利用具有不同扩张率的卷积路径有效提取轨迹数据的多尺度时序特征。最后,开发了语义聚焦(semantic focus,SF)模块以高效地捕捉轨迹数据中的关键信息。为验证所提方法的有效性,在农业农村部农机作业监测与大数据应用重点实验室提供的轨迹数据集上展开了实验。实验结果表明,MSINet在水稻收割机和小麦收割机轨迹数据集上的准确率分别为91.62%和91.34%,F1 score分别为91.57%和86.98%,相较于当前表现最优的模型生成式对抗网络-双向长短期记忆网络(generative adversarial network-bidirectional long short-term memory network,GAN BiLSTM),F1 score分别提升了5.57和3.72个百分点。展开更多
Recently, the IP connectivity during the Mobile Node (MN) movement between Base Stations (BSs) belonging to different Internet Service Providers (ISPs) is still a key issue to be tackled. In this paper, therefore, we ...Recently, the IP connectivity during the Mobile Node (MN) movement between Base Stations (BSs) belonging to different Internet Service Providers (ISPs) is still a key issue to be tackled. In this paper, therefore, we develop a new scheme to improve the performance of inter-domain fast handover over mobile WiMAX networks. The framework basically relies on the Fast Handover for Mobile IPv6 protocol (FMIPv6) when the Media Independent Information Services (MIIS) as defined in IEEE802.21 standard is applied to enable the Mobile Node in storing the information of the neighboring networks. A Fully Qualified Domain Name (FQDN) is also used to identify the IP address of the previous network operator and the MN during its movements. Since both MIIS and FQDN can support the node mobility between multiple domains, our proposed scheme can also be called P-FMIPv6. The numerical results show that the latency of IP connectivity of this proposed handover can be significantly reduced in addition to less service disruption time during handovers as compared to the existing FMIPv6 when IEEE802.16e network is considered.展开更多
文摘Recently, the IP connectivity during the Mobile Node (MN) movement between Base Stations (BSs) belonging to different Internet Service Providers (ISPs) is still a key issue to be tackled. In this paper, therefore, we develop a new scheme to improve the performance of inter-domain fast handover over mobile WiMAX networks. The framework basically relies on the Fast Handover for Mobile IPv6 protocol (FMIPv6) when the Media Independent Information Services (MIIS) as defined in IEEE802.21 standard is applied to enable the Mobile Node in storing the information of the neighboring networks. A Fully Qualified Domain Name (FQDN) is also used to identify the IP address of the previous network operator and the MN during its movements. Since both MIIS and FQDN can support the node mobility between multiple domains, our proposed scheme can also be called P-FMIPv6. The numerical results show that the latency of IP connectivity of this proposed handover can be significantly reduced in addition to less service disruption time during handovers as compared to the existing FMIPv6 when IEEE802.16e network is considered.
