This research investigates the impact of changing weather conditions on the crew members who sit in a side-by-side cockpit, which is unusual for attack helicopters. Extensive review conducted by the authors fails to l...This research investigates the impact of changing weather conditions on the crew members who sit in a side-by-side cockpit, which is unusual for attack helicopters. Extensive review conducted by the authors fails to locate similar studies;hence a helicopter simulator is developed in order to conduct the experiments. The simulator represents the realistic flight characteristics as well as the digital cockpit instruments that contain the advanced mission equipment. During the experiments, a camcorder is used to record the pilots to accurately analyze the task completion time and the physical motions of both pilots. NASA-TLX is also used to collect the workload data to assess the impact of task assignments among the pilots. The analytical findings from this study will be instrumental in improving the cockpit design for enhanced mission effectiveness.展开更多
针对升空通信平台大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统中在通信接入阶段遭受导频攻击引入的信息泄露问题,提出了一种基于空间波束不变性的导频接入攻击检测与消除方法。该方案基于用户空间波束域信道结构特征...针对升空通信平台大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统中在通信接入阶段遭受导频攻击引入的信息泄露问题,提出了一种基于空间波束不变性的导频接入攻击检测与消除方法。该方案基于用户空间波束域信道结构特征,在缺少信道先验信息的条件下使用点排序簇结构(Ordering Points to Identify the Clustering Structure,OPTICS)聚类算法,分离提取接入攻击与合法用户的波束域信道,消除接入攻击导致的信号损伤,实现合法用户信号安全传输。仿真结果表明,所提方案能够有效降低导频接入攻击对系统安全传输的影响。展开更多
文摘This research investigates the impact of changing weather conditions on the crew members who sit in a side-by-side cockpit, which is unusual for attack helicopters. Extensive review conducted by the authors fails to locate similar studies;hence a helicopter simulator is developed in order to conduct the experiments. The simulator represents the realistic flight characteristics as well as the digital cockpit instruments that contain the advanced mission equipment. During the experiments, a camcorder is used to record the pilots to accurately analyze the task completion time and the physical motions of both pilots. NASA-TLX is also used to collect the workload data to assess the impact of task assignments among the pilots. The analytical findings from this study will be instrumental in improving the cockpit design for enhanced mission effectiveness.
文摘针对升空通信平台大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统中在通信接入阶段遭受导频攻击引入的信息泄露问题,提出了一种基于空间波束不变性的导频接入攻击检测与消除方法。该方案基于用户空间波束域信道结构特征,在缺少信道先验信息的条件下使用点排序簇结构(Ordering Points to Identify the Clustering Structure,OPTICS)聚类算法,分离提取接入攻击与合法用户的波束域信道,消除接入攻击导致的信号损伤,实现合法用户信号安全传输。仿真结果表明,所提方案能够有效降低导频接入攻击对系统安全传输的影响。