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Widely linear UKF constant modulus algorithm for blind adaptive beamforming

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Journal of Systems Engineering and Electronics 2017年第3期28卷 413-423页

作者： huaming qian Ke Liu Long Li Linchen qian Junda Ma College of Automation Harbin Engineering University Advanced Signal Processing Lab College of EngineeringTemple University Information Communication Branch State Grid Heilongjiang Electric Power Company Limited School of Computing Beihang University

Based on a uniform linear array, a new widely linear unscented Kalman filter-based constant modulus algorithm (WL-UKF-CMA) for blind adaptive beamforming is proposed. The new algorithm is designed according to the constant modulus criterion and takes full advantage of the noncircular property of the signal of interest (SOI), significantly increasing the output signal-to interference-plus-noise ratio (SINR), enhancing the convergence speed and decreasing the steady-state misadjustment. Since it requires no known training data, the proposed algorithm saves a large amount of the available spectrum. Theoretical analysis and simulation results are presented to demonstrate its superiority over the conventional linear least mean square-based CMA (L-LMS-CMA), the conventional linear recursive least square-based CMA (L-RLS-CMA), WL-LMS-CMA, WL-RLS-CMA and L-UKF-CMA.

关键词： widely linear filtering blind beamforming noncircular signals constant modulus algorithm unscented Kalman filtering

Research on fiber optic gyro signal de-noising based on wavelet packet soft-threshold

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Journal of Systems Engineering and Electronics 2009年第3期20卷 607-612页

作者： qian huaming & Ma Jichen Coll.of Automation,Harbin Engineering Univ.,Harbin 150001,P.R.China Coll. of Automation Harbin Engineering Univ. Harbin 150001 P. R. China

Gyro＇s drift is not only the main drift error which influences gyro＇s precision but also the primary factor that affects gyro＇s reliability. Reducing zero drift and random drift is a key problem to the output of a gyro signal. A three-layer de-nosing threshold algorithm is proposed based on the wavelet decomposition to dispose the signal which is collected from a running fiber optic gyro （FOG）. The coefficients are obtained from the three-layer wavelet packet decomposition. By setting the high frequency part which is greater than wavelet packet threshold as zero, then reconstructing the nodes which have been filtered out noise and interruption, the soft threshold function is constructed by the coefficients of the third nodes. Compared wavelet packet de-noise with forced de-noising method, the proposed method is more effective. Simulation results show that the random drift compensation is enhanced by 13.1%, and reduces zero drift by 0.052 6°/h.

关键词： wavelet transform drift fiber optic gyro soft-threshold signal de-noising

Surface Doping *** Doping of Cathode Materials for Lithium-Ion Batteries:A Review

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Electrochemical Energy Reviews 2022年第4期5卷 254-285页

作者： huaming qian Haoqi Ren Ying Zhang Xianfeng He Wenbin Li Jingjing Wang Junhua Hu Hong Yang Hirbod Maleki Kheimeh Sari Yu Chen Xifei Li Xi’an Key Laboratory of New Energy Materials and Devices Institute of Advanced Electrochemical Energy and School of Materials Science and EngineeringXi’an University of TechnologyXi’an 710048ShaanxiChina Shaanxi International Joint Research Center of Surface Technology for Energy Storage Materials Xi’an 710048ShaanxiChina Department of Mechanical and Materials Engineering University of Western OntarioLondonOntario N6A 5B9Canada State Center for International Cooperation On Designer Low‑Carbon and Environmental Materials(CDLCEM) Zhengzhou University100 Kexue AvenueZhengzhou 450001China Xi’an Safty Energy Technology Co. LtdXi’an 710005ShaanxiChina

To address the capacity degradation,voltage fading,structural instability and adverse interface reactions in cathode materi-als of lithium-ion batteries(LIBs),numerous modification strategies have been developed,mainly including coating and *** particular,the important strategy of doping(surface doping and bulk doping)has been considered an effective strategy to modulate the crystal lattice structure of cathode ***,special insights into the mechanisms and effectiveness of the doping strategy,especially comparisons between surface doping and bulk doping in cathode materials,are still *** this review,recent significant progress in surface doping and bulk doping strategies is demonstrated in detail by focusing on their inherent differences as well as effects on the structural stability,lithium-ion(Li-ion)diffusion and electrochemical properties of cathode materials from the following mechanistic insights:preventing the exposure of reactive Ni on the surface,stabilizing the Li slabs,mitigating the migration of transition metal(TM)ions,alleviating unde-sired structural transformations and adverse interface issues,enlarging the Li interslab spacing,forming three-dimensional(3D)Li-ion diffusion channels,and providing more active sites for the charge-transfer ***,insights into the correlation between the mechanisms of hybrid surface engineering strategies(doping and coating)and their influences on the electrochemical performance of cathode materials are provided by emphasizing the stabilization of the Li slabs,the enhancement of the surface chemical stability,and the alleviation of TM ion ***,the existing challenges and future perspectives in this promising field are indicated.

关键词： Lithium-ion batteries Cathode materials Surface doping Bulk doping Hybrid surface engineering Structural stability Lithium-ion diffusion

Iterated Unscented Kalman Filter for Spacecraft Attitude Estimation

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Iterated Unscented Kalman Filter for Spacecraft Attitude Est...

第37届中国控制会议

作者： huaming qian Zhenbing Qiu College of Automation Harbin Engineering University

In this paper, an iterated unscented quaternion estimator for spacecraft attitude estimation is proposed. A step length-varying iteration technique is incorporated into the unscented quaternion estimator and the corresponding termination condition is introduced to control the number of iterations and reduce the computational burden. The reference quaternion in the measurement update is redefined by the developed iteration technique. Simulation results demonstrate the superiority of the proposed new algorithm in comparison with the multiplicative extended Kalman filter, norm constraint Kalman filter and the unscented quaternion estimator under large initialization condition errors. It also shows that the proposed algorithm exhibits a faster convergence rate.

关键词： unscented quaternion estimator attitude estimation iteration technique reference quaternion

来源： cnki会议评论

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一种基于多通道卫星云图的台风分割方法

北京航空航天大学学报 2011年第4期37卷 466-471页

作者：钱华明姜波哈尔滨工程大学自动化学院哈尔滨150001

有效的台风主体分割能够提高台风预报的准确性.提出一种基于矢量图像的改进水平集方法进行台风分割,将C-V模型推广到矢量空间,加入了无需重新初始化的能量项;提出了一种迭代收敛条件并设计了针对云图特点的模型参数及分割方法,该方法利... 详细信息

有效的台风主体分割能够提高台风预报的准确性.提出一种基于矢量图像的改进水平集方法进行台风分割,将C-V模型推广到矢量空间,加入了无需重新初始化的能量项;提出了一种迭代收敛条件并设计了针对云图特点的模型参数及分割方法,该方法利用了多通道的云图信息,避免了无谓的迭代计算,能够加快分割曲线的演化速度并提高分割的准确性.实验结果验证了所提出方法的有效性和可行性,其平均目标错误率与平均非目标错误率分别为1.21%与2.25%,可得到较理想的台风分割效果.

关键词：图像分割水平集 C-V模型卫星图像气象预报

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四元数约束的容积卡尔曼滤波及其应用

哈尔滨工业大学学报 2014年第7期46卷 40-46页

作者：钱华明黄蔚孙龙哈尔滨工程大学自动化学院哈尔滨150001

针对一些非线性系统状态变量中存在四元数约束的情况,提出了一种四元数约束下的容积卡尔曼滤波(quaternion constrained cubature kalman filter,QCCKF)算法.基于最小约束代价函数,采用三阶球面-相径容积规则近似计算系统状态的后验均... 详细信息

针对一些非线性系统状态变量中存在四元数约束的情况,提出了一种四元数约束下的容积卡尔曼滤波(quaternion constrained cubature kalman filter,QCCKF)算法.基于最小约束代价函数,采用三阶球面-相径容积规则近似计算系统状态的后验均值和协方差,给出了QCCKF滤波递推公式.设计的QCCKF算法可以有效地对状态进行估计,扩展了CKF的应用范围.最后对飞行器姿态估计系统进行仿真,仿真结果表明,该算法估计精度优于常规CKF和无迹四元数估计法(unscented quaternion estimator,USQUE),并满足四元数约束条件,较好地解决了非线性系统存在四元数约束的问题,验证了算法的有效性.

关键词：容积卡尔曼滤波四元数约束最小约束代价函数三阶球面-相径容积规则

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基于改进的迭代容积卡尔曼滤波姿态估计

哈尔滨工业大学学报 2014年第6期46卷 116-122页

作者：钱华明黄蔚孙龙哈尔滨工程大学自动化学院哈尔滨150001

为了充分利用新的量测信息,提高姿态估计的精度,在分析现有迭代滤波策略存在问题的基础上,采用一种新的容积点迭代策略,将其与容积卡尔曼滤波算法相结合,提出了一种改进的迭代容积卡尔曼滤波(improved iterated cubature Kalman filter,... 详细信息

为了充分利用新的量测信息,提高姿态估计的精度,在分析现有迭代滤波策略存在问题的基础上,采用一种新的容积点迭代策略,将其与容积卡尔曼滤波算法相结合,提出了一种改进的迭代容积卡尔曼滤波(improved iterated cubature Kalman filter,IICKF)算法.该算法采用容积数值积分理论近似非线性函数的均值与方差,利用状态扩维理论来解决量测迭代中量测噪声与状态相关的问题,同时利用一种新的容积点迭代策略,即在量测迭代过程中直接采用容积点迭代,避免每步迭代都进行均方根计算来产生容积点,克服传统迭代策略是基于高斯近似产生采样点的局限,有效地降低扩维带来的计算量.仿真结果表明:该算法的估计精度高于乘性扩展卡尔曼滤波(multiplicative extended Kalman filter,MEKF)以及迭代容积卡尔曼滤波(iterated cubature Kalman filter,ICKF)算法,该算法的提出有助于提高姿态估计的精度.

关键词：姿态估计改进的迭代容积卡尔曼滤波容积数值积分理论状态扩维估计精度

结合时域信息的区域生长算法及其在动脉超声造影图像分割中的应用

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计算机辅助设计与图形学学报 2011年第3期23卷 442-447页

作者：钱华明姜波钱明郑海荣哈尔滨工程大学自动化学院哈尔滨150001 中国科学院深圳先进技术研究院生物医学与健康工程研究所劳特伯生物医学成像研究中心深圳518055 中国科学院生物医学信息与健康工程学重点实验室深圳518055

为了有效地提取动脉超声造影图像中的血管边界,提高动脉内膜附近血流流场超声测量的准确性,提出一种结合时域信息的区域增长算法进行动脉超声造影图像的血管边界分割.该算法根据超声造影微泡在血液内的流动特性,利用连续两帧图像之间的... 详细信息

为了有效地提取动脉超声造影图像中的血管边界,提高动脉内膜附近血流流场超声测量的准确性,提出一种结合时域信息的区域增长算法进行动脉超声造影图像的血管边界分割.该算法根据超声造影微泡在血液内的流动特性,利用连续两帧图像之间的灰度差异构造窗帧差,令其作为生长条件,结合邻域灰度进行区域生长;采用数学形态学的闭合运算与一种自定义的边界平滑方法对区域生长结果进行处理,填补了区域生长中产生的空洞并平滑了不规则边界.最后通过大鼠颈动脉的超声造影图像实验,验证了文中算法的有效性和可行性,该算法能够准确地提取出模糊的动脉边界,时间复杂度低.

关键词：图像分割区域生长超声造影图像动脉分割超声粒子图像测速

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一种基于导向矢量约束的恒模盲波束形成算法

哈尔滨工业大学学报 2016年第9期48卷 151-156页

作者：刘可钱华明马俊达哈尔滨工程大学自动化学院哈尔滨150001

针对阵列信号波达角(direction of arrival,DOA)先验信息已知的情况,利用信号的恒模特性,在卡尔曼滤波(Kalman filter,KF)结构下,提出一种附加阵列导向矢量约束的自适应波束形成算法.对约束情况下的卡尔曼滤波目标函数运用拉格朗日乘子... 详细信息

针对阵列信号波达角(direction of arrival,DOA)先验信息已知的情况,利用信号的恒模特性,在卡尔曼滤波(Kalman filter,KF)结构下,提出一种附加阵列导向矢量约束的自适应波束形成算法.对约束情况下的卡尔曼滤波目标函数运用拉格朗日乘子法,求得约束条件下的最优估计表达式,并将其推广到无迹卡尔曼滤波(unscented Kalman filter,UKF)算法中,通过约束迭代算法对阵列估计信号的导向角施加约束,实现约束UKF自适应波束形成算法的最优权值分配.仿真过程中,用所提算法与约束恒模迭代最小二乘算法和约束最小方差迭代最小二乘算法作对比,表明表明,该算法在收敛速度、信噪比、稳健性、跟踪性能方面具有较好的性能.

关键词：信号处理自适应滤波无迹卡尔曼滤波波束形成约束优化技术