An effective automatic target detection algorithm based on wavelet transform,which takes advantage of the localization and the orientation of wavelet analysis,is proposed.The algorithm detects the target in the vertic...An effective automatic target detection algorithm based on wavelet transform,which takes advantage of the localization and the orientation of wavelet analysis,is proposed.The algorithm detects the target in the vertical component of the wavelet transformation of the image.After mutual energy combination and sea clutter suppression through spatial weighting and thresholding,the target is located through maximum energy determination and its size is indicated through similarity measurement function of two overlapping windows.Experiment results show that the target can be detected by the algorithm in a single image frame and the better efficiency can be obtained also under the complicated backgrounds of existing the disturbances of cloud layer and fish scale light.展开更多
目的探究视觉反馈对人体静止直立姿态的镇定作用及其发生机制。方法考察12名青年志愿者在直立(对照)状态和直立并视觉反馈状态下足底压力中心(center of pressure,COP)的变化。利用布朗运动模型对比两种状态下COP轨迹的扩散系数、Hurst...目的探究视觉反馈对人体静止直立姿态的镇定作用及其发生机制。方法考察12名青年志愿者在直立(对照)状态和直立并视觉反馈状态下足底压力中心(center of pressure,COP)的变化。利用布朗运动模型对比两种状态下COP轨迹的扩散系数、Hurst指数及临界点特性变化,并通过单因素重复测量方差分析检验其差异显著性。结果视觉反馈状态下:长期区间上,Hurst指数减小约1/2,扩散系数减小约2/3;短期区间上,Hurst指数与左右方向扩散系数均无显著变化;临界点均方位移仅在前后方向显著增大,时间间隔变化不显著。结论视觉反馈增强了人体姿态闭环控制,但对开环控制及开、闭环控制机制的切换特性影响不大;视觉反馈对人体姿态控制的作用表现出方向差异,前后方向上的视觉反馈作用比左右方向更为明显。展开更多
文摘An effective automatic target detection algorithm based on wavelet transform,which takes advantage of the localization and the orientation of wavelet analysis,is proposed.The algorithm detects the target in the vertical component of the wavelet transformation of the image.After mutual energy combination and sea clutter suppression through spatial weighting and thresholding,the target is located through maximum energy determination and its size is indicated through similarity measurement function of two overlapping windows.Experiment results show that the target can be detected by the algorithm in a single image frame and the better efficiency can be obtained also under the complicated backgrounds of existing the disturbances of cloud layer and fish scale light.
文摘目的探究视觉反馈对人体静止直立姿态的镇定作用及其发生机制。方法考察12名青年志愿者在直立(对照)状态和直立并视觉反馈状态下足底压力中心(center of pressure,COP)的变化。利用布朗运动模型对比两种状态下COP轨迹的扩散系数、Hurst指数及临界点特性变化,并通过单因素重复测量方差分析检验其差异显著性。结果视觉反馈状态下:长期区间上,Hurst指数减小约1/2,扩散系数减小约2/3;短期区间上,Hurst指数与左右方向扩散系数均无显著变化;临界点均方位移仅在前后方向显著增大,时间间隔变化不显著。结论视觉反馈增强了人体姿态闭环控制,但对开环控制及开、闭环控制机制的切换特性影响不大;视觉反馈对人体姿态控制的作用表现出方向差异,前后方向上的视觉反馈作用比左右方向更为明显。
