A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α whi...A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions.展开更多
The method of using a narrowband filter to realize matched filtering is derived.A novel method of using spectrum sampling to realize matched filtering is presented,and the method can conquer the disadvantages that the...The method of using a narrowband filter to realize matched filtering is derived.A novel method of using spectrum sampling to realize matched filtering is presented,and the method can conquer the disadvantages that the narrowband filter cannot adopt the adaptive scheduling of phased array radars and realize matched filtering for several waveforms.A novel error extraction method is proposed,which uses a time division multipath method to realize the intermediate frequency extraction.This method can save lots of space for vehicle-born radar systems,reduce the influence of amplitude and phase distortion caused by devices,and enhance the system reliability.Simulation results show that the spectrum sampling method is applicable,and the implementation of frequency spectrum sampling is elaborated.展开更多
The distributed passive measurement is an important technology for networkbehavior research. To achieve a consistent measurement, the same packets should be sampled atdistributed measurement points. And in order to es...The distributed passive measurement is an important technology for networkbehavior research. To achieve a consistent measurement, the same packets should be sampled atdistributed measurement points. And in order to estimate the character of traffic statistics, thetraffic sample should be random in statistics. A distributed samplingmask measurement model isintroduced to tackle the difficulty of measuring the full trace of high-speed networks. The keypoint of the model is to choose some bits that are suitable to be sampling mask. In the paper, thebit entropy and bit flow entropy of IP packet headers in CERNET backbone are analyzed, and we findthat the 16 bits of identification field in IP packet header are fit to the matching field ofsampling mask. Measurement traffic also can be used to analyze the statistical character ofmeasurement sample and the randomicity of the model. At the same time the experiment resultsindicate that the model has a good sampling performance.展开更多
This paper addresses an algebraic approach for wideband frequency estimation with sub-Nyquist temporal sampling. Firstly, an algorithm based on double polynomial root finding procedure to estimate aliasing frequencies...This paper addresses an algebraic approach for wideband frequency estimation with sub-Nyquist temporal sampling. Firstly, an algorithm based on double polynomial root finding procedure to estimate aliasing frequencies and joint aliasing frequencies-time delay phases in multi-signal situation is presentcd. Since the sum of time delay phases determined from the least squares estimation shows the characteristics of the corre- sponding parameters pairs, then the pairmatching method is conducted by combining it with estimated parameters mentioned above. Although the proposed method is computationally simpler than the conventional schemes, simulation results show that it can approach optimum estimation performance.展开更多
In order to improve target localization precision,accuracy,execution efficiency,and application range of the unmanned aerial vehicle(UAV)based on scene matching,a ground target localization method for unmanned aerial ...In order to improve target localization precision,accuracy,execution efficiency,and application range of the unmanned aerial vehicle(UAV)based on scene matching,a ground target localization method for unmanned aerial vehicle based on scene matching(GTLUAVSM)is proposed.The sugges-ted approach entails completing scene matching through a feature matching algorithm.Then,multi-sensor registration is optimized by robust estimation based on homologous registration.Finally,basemap generation and model solution are utilized to improve basemap correspondence and accom-plish aerial image positioning.Theoretical evidence and experimental verification demonstrate that GTLUAVSM can improve localization accuracy,speed,and precision while minimizing reliance on task equipment.展开更多
针对散料杂货港口需要检测靠离泊大型散货船以避免事故的需求,考虑到船体方形系数大的特点,将完整船体的检测任务简化为对船只近岸侧外壁的平面特征提取任务,因此,提出了一种基于快速点特征直方图(Fast point feature histogram,FPFH)...针对散料杂货港口需要检测靠离泊大型散货船以避免事故的需求,考虑到船体方形系数大的特点,将完整船体的检测任务简化为对船只近岸侧外壁的平面特征提取任务,因此,提出了一种基于快速点特征直方图(Fast point feature histogram,FPFH)的模板匹配与改进的M采样估计一致性(M-estimate sample consensus,MSAC)平面拟合的船只近岸侧外壁平面特征提取方法。首先根据现场情况等先验知识设定模板点云,在采集原始点云后进行预处理,获得目标点云;然后估计法向量,计算FPFH特征并进行模板匹配,获得船只近岸侧外壁平面点云;根据船只近岸侧外壁平面点云的法向量方向进行层次密度聚类(Hierarchical density-based spatial clustering of applications with noise,HDBSCAN),再进行考虑法向量因子的MSAC平面拟合,从而提取出靠离泊船只近岸侧外壁的平面特征。经现场数据验证,该方法比现有方法具有更低的平均相对误差,且处理每帧点云用时的标准差也更低,帧均用时也低于雷达每帧采样用时,可以满足现场实时性需求。展开更多
针对工业场景下经典迭代最近点(iterative closest point,ICP)算法在点云位姿估计中初始位姿敏感度高、迭代时间长的问题,提出一种基于RGB图像的快速点云配准方法。分别采集RGB图像和点云数据,使用ORB(oriented FAST and rotated BRIEF...针对工业场景下经典迭代最近点(iterative closest point,ICP)算法在点云位姿估计中初始位姿敏感度高、迭代时间长的问题,提出一种基于RGB图像的快速点云配准方法。分别采集RGB图像和点云数据,使用ORB(oriented FAST and rotated BRIEF)算法提取RGB图像特征点,利用Brute-Force算法进行初始匹配,采用随机采样一致性算法优化匹配,得到单应矩阵和旋转平移矩阵,求解汽车零配件初始位姿。进一步采用主成分分析法和双向KD树近邻搜索算法对预处理后的点云数据进行精确配准。实验结果表明,所提算法相较ICP算法,在配准速度和精度上分别提高了87.2%和5.0%,相对于FR-ICP(fast and robust iterative closest point)算法,在配准精度相当的情况下,配准速度提高了55%。展开更多
文摘A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions.
文摘The method of using a narrowband filter to realize matched filtering is derived.A novel method of using spectrum sampling to realize matched filtering is presented,and the method can conquer the disadvantages that the narrowband filter cannot adopt the adaptive scheduling of phased array radars and realize matched filtering for several waveforms.A novel error extraction method is proposed,which uses a time division multipath method to realize the intermediate frequency extraction.This method can save lots of space for vehicle-born radar systems,reduce the influence of amplitude and phase distortion caused by devices,and enhance the system reliability.Simulation results show that the spectrum sampling method is applicable,and the implementation of frequency spectrum sampling is elaborated.
文摘The distributed passive measurement is an important technology for networkbehavior research. To achieve a consistent measurement, the same packets should be sampled atdistributed measurement points. And in order to estimate the character of traffic statistics, thetraffic sample should be random in statistics. A distributed samplingmask measurement model isintroduced to tackle the difficulty of measuring the full trace of high-speed networks. The keypoint of the model is to choose some bits that are suitable to be sampling mask. In the paper, thebit entropy and bit flow entropy of IP packet headers in CERNET backbone are analyzed, and we findthat the 16 bits of identification field in IP packet header are fit to the matching field ofsampling mask. Measurement traffic also can be used to analyze the statistical character ofmeasurement sample and the randomicity of the model. At the same time the experiment resultsindicate that the model has a good sampling performance.
文摘This paper addresses an algebraic approach for wideband frequency estimation with sub-Nyquist temporal sampling. Firstly, an algorithm based on double polynomial root finding procedure to estimate aliasing frequencies and joint aliasing frequencies-time delay phases in multi-signal situation is presentcd. Since the sum of time delay phases determined from the least squares estimation shows the characteristics of the corre- sponding parameters pairs, then the pairmatching method is conducted by combining it with estimated parameters mentioned above. Although the proposed method is computationally simpler than the conventional schemes, simulation results show that it can approach optimum estimation performance.
基金the National Key R&D Program of China(2022YFF0604502).
文摘In order to improve target localization precision,accuracy,execution efficiency,and application range of the unmanned aerial vehicle(UAV)based on scene matching,a ground target localization method for unmanned aerial vehicle based on scene matching(GTLUAVSM)is proposed.The sugges-ted approach entails completing scene matching through a feature matching algorithm.Then,multi-sensor registration is optimized by robust estimation based on homologous registration.Finally,basemap generation and model solution are utilized to improve basemap correspondence and accom-plish aerial image positioning.Theoretical evidence and experimental verification demonstrate that GTLUAVSM can improve localization accuracy,speed,and precision while minimizing reliance on task equipment.
文摘针对散料杂货港口需要检测靠离泊大型散货船以避免事故的需求,考虑到船体方形系数大的特点,将完整船体的检测任务简化为对船只近岸侧外壁的平面特征提取任务,因此,提出了一种基于快速点特征直方图(Fast point feature histogram,FPFH)的模板匹配与改进的M采样估计一致性(M-estimate sample consensus,MSAC)平面拟合的船只近岸侧外壁平面特征提取方法。首先根据现场情况等先验知识设定模板点云,在采集原始点云后进行预处理,获得目标点云;然后估计法向量,计算FPFH特征并进行模板匹配,获得船只近岸侧外壁平面点云;根据船只近岸侧外壁平面点云的法向量方向进行层次密度聚类(Hierarchical density-based spatial clustering of applications with noise,HDBSCAN),再进行考虑法向量因子的MSAC平面拟合,从而提取出靠离泊船只近岸侧外壁的平面特征。经现场数据验证,该方法比现有方法具有更低的平均相对误差,且处理每帧点云用时的标准差也更低,帧均用时也低于雷达每帧采样用时,可以满足现场实时性需求。
文摘针对工业场景下经典迭代最近点(iterative closest point,ICP)算法在点云位姿估计中初始位姿敏感度高、迭代时间长的问题,提出一种基于RGB图像的快速点云配准方法。分别采集RGB图像和点云数据,使用ORB(oriented FAST and rotated BRIEF)算法提取RGB图像特征点,利用Brute-Force算法进行初始匹配,采用随机采样一致性算法优化匹配,得到单应矩阵和旋转平移矩阵,求解汽车零配件初始位姿。进一步采用主成分分析法和双向KD树近邻搜索算法对预处理后的点云数据进行精确配准。实验结果表明,所提算法相较ICP算法,在配准速度和精度上分别提高了87.2%和5.0%,相对于FR-ICP(fast and robust iterative closest point)算法,在配准精度相当的情况下,配准速度提高了55%。
