Doppler blind zone （DBZ） has a bad influence on the airborne early warning radar, although it has good detection performance for low altitude targets with pulse Doppler （PD） technology. In target tracking, the bli...Doppler blind zone （DBZ） has a bad influence on the airborne early warning radar, although it has good detection performance for low altitude targets with pulse Doppler （PD） technology. In target tracking, the blind zone can cause target tracking breakage easily. In order to solve this problem, a parallel particle filter （PF） algorithm based on multi-hypothesis motion models （MHMMs） is proposed. The algorithm produces multiple possible target motion models according to the DBZ constraint. Particles are updated with the constraint in each motion model. Once the first measurement from the target which reappears from DBZ falls into the particle cloud formed by any model, the measurementtrack association succeeds and track breakage is avoided. The simulation results show that on the condition of different DBZ ranges, a high association ratio can be got for targets with different maneuverability levels, which accordingly improves the tracking quality.展开更多
图片自动语义标注是基于内容图像检索中很重要且很有挑战性的工作。本文提出了一种基于Boosting学习的图片自动语义标注方法,建立了一个图片语义标注系统BLIR(boosting for lingu istic indexing im age retrievalsystem)。假设一组具...图片自动语义标注是基于内容图像检索中很重要且很有挑战性的工作。本文提出了一种基于Boosting学习的图片自动语义标注方法,建立了一个图片语义标注系统BLIR(boosting for lingu istic indexing im age retrievalsystem)。假设一组具有同一语义的图像能够用一个由一组特征组合而成的视觉模型来表示。2D-MHMM(2维多分辨率隐马尔科夫模型)实际上就是一种颜色和纹理特殊组合的模板。BLIR系统首先生成大量的2D-MHMM模型,然后用Boosting算法来实现关键词与2D-MHMM模型的关联。在一个包含60 000张图像的图库上实现并测试了这个系统。结果表明,对这些测试图像,BLIR方法比其他方法具有更高的检索正确率。展开更多
基金supported by the Academy Innovation Fund Project (2013QNCX0101)
文摘Doppler blind zone （DBZ） has a bad influence on the airborne early warning radar, although it has good detection performance for low altitude targets with pulse Doppler （PD） technology. In target tracking, the blind zone can cause target tracking breakage easily. In order to solve this problem, a parallel particle filter （PF） algorithm based on multi-hypothesis motion models （MHMMs） is proposed. The algorithm produces multiple possible target motion models according to the DBZ constraint. Particles are updated with the constraint in each motion model. Once the first measurement from the target which reappears from DBZ falls into the particle cloud formed by any model, the measurementtrack association succeeds and track breakage is avoided. The simulation results show that on the condition of different DBZ ranges, a high association ratio can be got for targets with different maneuverability levels, which accordingly improves the tracking quality.
文摘图片自动语义标注是基于内容图像检索中很重要且很有挑战性的工作。本文提出了一种基于Boosting学习的图片自动语义标注方法,建立了一个图片语义标注系统BLIR(boosting for lingu istic indexing im age retrievalsystem)。假设一组具有同一语义的图像能够用一个由一组特征组合而成的视觉模型来表示。2D-MHMM(2维多分辨率隐马尔科夫模型)实际上就是一种颜色和纹理特殊组合的模板。BLIR系统首先生成大量的2D-MHMM模型,然后用Boosting算法来实现关键词与2D-MHMM模型的关联。在一个包含60 000张图像的图库上实现并测试了这个系统。结果表明,对这些测试图像,BLIR方法比其他方法具有更高的检索正确率。
