For short-term wind power forecasting,an interval A2-C1 type-2(IT2)Takagi-Sugeno-Kang(TSK)fuzzy logic system(FLS)method(“A”means antecedent and“C”consequent)based on an extended Kalman filter(EKF)optimization algo...For short-term wind power forecasting,an interval A2-C1 type-2(IT2)Takagi-Sugeno-Kang(TSK)fuzzy logic system(FLS)method(“A”means antecedent and“C”consequent)based on an extended Kalman filter(EKF)optimization algorithm is proposed.Compared with the type-1(T1)FLS model,the IT2 TSK FLS method can simultaneously model both intra-and inter-individual uncertainty and further optimize the antecedent and consequent parameters using the EKF to improve forecasting performance further.The proposed IT2 A2-C1 FLS method is applied to Mackey-Glass chaotic time series and wind power forecasting instances in a certain region,under the same conditions.It is also compared with the T1 TSK FLS and IT2 TSK FLS methods with back propagation(BP)and particle swarm optimization(PSO)algorithms,as well as IT2 A2-C0 TSK FLS methods with EKF.The experimental results confirm that the proposed IT2 A2-C1 FLS method is superior to the other FLS methods regarding performance,which demonstrates its effectiveness and application potential.展开更多
The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysi...The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysis of the proposed distributed KF algorithm without independent and stationary signal assumptions,which implies that the theoretical results are able to be applied to stochastic feedback systems.Note that the main difficulty of stability analysis lies in analyzing the properties of the product of non-independent and non-stationary random matrices involved in the error equation.We employ analysis techniques such as stochastic Lyapunov function,stability theory of stochastic systems,and algebraic graph theory to deal with the above issue.The stochastic spatio-temporal cooperative information condition shows the cooperative property of multiple sensors that even though any local sensor cannot track the time-varying unknown signal,the distributed KF algorithm can be utilized to finish the filtering task in a cooperative way.At last,we illustrate the property of the proposed distributed KF algorithm by a simulation example.展开更多
This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic systems.To deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propos...This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic systems.To deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)algorithm.Our algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional space.Subsequently,the original high-dimensional sparse signals can be well recovered by a reconstruction technique.To ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback systems.We further present the performance of the compressed KF algorithm.Specifically,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and optimized.Finally,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.展开更多
Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcomin...Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcoming, Kalman filtering algorithm for this series is established,and its correctness and validity are verified with the test data obtained on the movable platform in plane. The results show that Kalman filtering can improve the correctness, reliability and stability of the deformation information series.展开更多
[目的/意义]针对温室温湿度预测中多传感器数据融合可靠性低、传统模型忽略温湿度动态耦合,以及参数调优依赖人工经验等问题。[方法]首先,对传统卡尔曼(Kalman)滤波算法实施改进,通过动态调整过程噪声协方差和观测噪声协方差,结合新息...[目的/意义]针对温室温湿度预测中多传感器数据融合可靠性低、传统模型忽略温湿度动态耦合,以及参数调优依赖人工经验等问题。[方法]首先,对传统卡尔曼(Kalman)滤波算法实施改进,通过动态调整过程噪声协方差和观测噪声协方差,结合新息方差动态分配多传感器权重。其次,针对温湿度的强耦合性及其协同控制的需求,构建多输出长短期记忆-注意力机制(Long Short-Term Memory-Attention,LSTM-Attention)模型,以温湿度协同预测为目标,引入注意力机制自适应加权关键环境因子,并采用灰狼优化算法(Grey Wolf Optimizer,GWO)自动对超参数进行寻优。[结果和讨论]提出的自适应卡尔曼滤波算法在多点温湿度融合中的平均绝对偏差分别为1.59℃和8.64%,比传统卡尔曼滤波算法分别降低1.24%、8.57%。以该算法融合结果作为模型训练集,模型在温湿度预测中决定系数R2分别达到98.2%和99.3%,比传统Kalman提升4.7%和4.3%。GWO-LSTM-Atten⁃tion模型的温湿度预测均方根误差分别为0.7768℃和2.0564%,比LSTM、LSTM-Attention时间序列预测模型分别降低15.6%、6.6%,湿度分别降低29.2%、5.7%。[结论]提出的自适应卡尔曼融合算法能够有效抑制异常值影响,可在非平稳环境变化下实现多传感器数据可靠融合。在温室多环境因子预测中,GWO-LSTM-Attention模型温湿度预测值在未来可作为控制温室环境的重要参考,进而实现对温室环境的实时调控。展开更多
Data assimilation in agricultural remote sensing research is of great significance to integrate with remote sensing observations and model simulations for parameters estimation. The present investigation not only desi...Data assimilation in agricultural remote sensing research is of great significance to integrate with remote sensing observations and model simulations for parameters estimation. The present investigation not only designed and realized the Ensemble Kalman Filtering algorithm (EnKF) assimilation by combing the crop growth model (CERES-Wheat) with remote sensing data, but also optimized and updated the key parameters (LAI) of winter wheat by using remote sensing data. Results showed that the assimilation LAI and the observation ones agreed with each other, and the R2 reached 0.8315. So assimilation remote sensing and crop model could provide reference data for the agricultural production.展开更多
The standalone Global Positioning System (GPS) does not meet the higher accuracy requirements needed for approach and landing phase of an aircraft. To meet the Category-I Precision Approach (CAT-I PA) requirements of ...The standalone Global Positioning System (GPS) does not meet the higher accuracy requirements needed for approach and landing phase of an aircraft. To meet the Category-I Precision Approach (CAT-I PA) requirements of civil aviation, satellite based augmentation system (SBAS) has been planned by various countries including USA, Europe, Japan and India. The Indian SBAS is named as GPS Aided Geo Augmented Navigation (GAGAN). The GAGAN network consists of several dual frequency GPS receivers located at various airports around the Indian subcontinent. The ionospheric delay, which is a function of the total electron content (TEC), is one of the main sources of error affecting GPS/SBAS accuracy. A dual frequency GPS receiver can be used to estimate the TEC. However, line-of-sight TEC derived from dual frequency GPS data is corrupted by the instrumental biases of the GPS receiver and satellites. The estimation of receiver instrumental bias is particularly important for obtaining accurate estimates of ionospheric delay. In this paper, two prominent techniques based on Kalman filter and Self-Calibration Of pseudo Range Error (SCORE) algorithm are used for estimation of instrumental biases. The estimated instrumental bias and TEC results for the GPS Aided Geo Augmented Navigation (GAGAN) station at Hyderabad (78.47°E, 17.45°N), India are presented.展开更多
Because of the ignored items after linearization,the extended Kalman filter(EKF)becomes a form of suboptimal gradient descent algorithm.The emanative tendency exists in GPS solution when the filter equations are ill-p...Because of the ignored items after linearization,the extended Kalman filter(EKF)becomes a form of suboptimal gradient descent algorithm.The emanative tendency exists in GPS solution when the filter equations are ill-posed.The deviation in the estimation cannot be avoided.Furthermore,the true solution may be lost in pseudorange positioning because the linearized pseudorange equations are partial solutions.To solve the above problems in GPS dynamic positioning by using EKF,a closed-form Kalman filter method called the two-stage algorithm is presented for the nonlinear algebraic solution of GPS dynamic positioning based on the global nonlinear least squares closed algorithm--Bancroft numerical algorithm of American.The method separates the spatial parts from temporal parts during processing the GPS filter problems,and solves the nonlinear GPS dynamic positioning,thus getting stable and reliable dynamic positioning solutions.展开更多
The fading factor exerts a significant role in the strong tracking idea. However, traditional fading factor introduction method hinders the accuracy and robustness advantages of current strong-tracking-based nonlinear...The fading factor exerts a significant role in the strong tracking idea. However, traditional fading factor introduction method hinders the accuracy and robustness advantages of current strong-tracking-based nonlinear filtering algorithms such as Cubature Kalman Filter(CKF) since traditional fading factor introduction method only considers the first-order Taylor expansion. To this end, a new fading factor idea is suggested and introduced into the strong tracking CKF method.The new fading factor introduction method expanded the number of fading factors from one to two with reselected introduction positions. The relationship between the two fading factors as well as the general calculation method can be derived based on Taylor expansion. Obvious superiority of the newly suggested fading factor introduction method is demonstrated according to different nonlinearity of the measurement function. Equivalent calculation method can also be established while applied to CKF. Theoretical analysis shows that the strong tracking CKF can extract the thirdorder term information from the residual and thus realize second-order accuracy. After optimizing the strong tracking algorithm process, a Fast Strong Tracking CKF(FSTCKF) is finally established. Two simulation examples show that the novel FSTCKF improves the robustness of traditional CKF while minimizing the algorithm time complexity under various conditions.展开更多
针对无线传感器网络中基于接收信号强度指示(Received Signal Strength Indicator,RSSI)定位技术易受环境影响、定位精度较低的问题,提出一种将RSSI定位过程分为测距阶段与定位阶段的双阶段优化方法。测距阶段,改进卡尔曼滤波算法以RSS...针对无线传感器网络中基于接收信号强度指示(Received Signal Strength Indicator,RSSI)定位技术易受环境影响、定位精度较低的问题,提出一种将RSSI定位过程分为测距阶段与定位阶段的双阶段优化方法。测距阶段,改进卡尔曼滤波算法以RSSI信号均值作为初始状态估计,结合网格遍历搜索优化过程噪声协方差和测量噪声协方差参数,提升卡尔曼滤波算法的适应性和滤波效果,降低测距阶段的误差;定位阶段,使用多策略改进鲸鱼优化的节点位置估计算法求解未知节点位置,进一步提高定位精度。该算法通过K-means聚类初始化策略、精英反向学习策略和随机鲸鱼学习策略,提升原始鲸鱼优化算法的全局搜索能力和收敛速度,进一步提高定位精度。实验结果表明,该双阶段优化方法在定位误差控制方面优于传统的单阶段优化策略,具备更高的定位精度与更强的环境适应能力,并在与其他对比算法的性能比较中展现出明显优势。展开更多
无迹卡尔曼滤波(unscented Kalman filter,UKF)是锂离子电池荷电状态(state of charge,SOC)估计的常用算法之一。然而在实际应用中,由于受到外界环境温度变化、电池容量退化等不确定性干扰,以及非高斯过程噪声的影响,需要进一步提高算...无迹卡尔曼滤波(unscented Kalman filter,UKF)是锂离子电池荷电状态(state of charge,SOC)估计的常用算法之一。然而在实际应用中,由于受到外界环境温度变化、电池容量退化等不确定性干扰,以及非高斯过程噪声的影响,需要进一步提高算法的性能才能更有效地保证估计精度。基于此,提出一种改进的无迹卡尔曼滤波算法(PO-RUKF)。首先,在UKF中引入H∞滤波提高算法的鲁棒性,用来克服各种干扰带来的不良影响。其次,利用鹦鹉优化算法对UKF的过程噪声协方差矩阵进行自适应调整,以解决滤波噪声参数先验确定的问题,从而提高滤波精度。最后,采用马里兰大学的FUDS和HPPC工况下的两种公开数据集进行了实验验证,结果表明,在不同的温度、电池容量退化状态以及不同的工况下,相比于传统的UKF算法以及鲁棒UKF算法,改进后的算法具有更高的SOC估计精度,平均绝对误差小于0.50%,均方根误差小于0.56%,此外还展现出更强的鲁棒性和普适性。证实所提方法可以为锂离子电池SOC估计提供更可靠、有效的技术支撑。展开更多
基金Supported by the Key Project of Natural Science Foundation of Gansu Province(25JRRA150)the Gansu Provincial Natural Science Foundation(23JRRA876).
摘要For short-term wind power forecasting,an interval A2-C1 type-2(IT2)Takagi-Sugeno-Kang(TSK)fuzzy logic system(FLS)method(“A”means antecedent and“C”consequent)based on an extended Kalman filter(EKF)optimization algorithm is proposed.Compared with the type-1(T1)FLS model,the IT2 TSK FLS method can simultaneously model both intra-and inter-individual uncertainty and further optimize the antecedent and consequent parameters using the EKF to improve forecasting performance further.The proposed IT2 A2-C1 FLS method is applied to Mackey-Glass chaotic time series and wind power forecasting instances in a certain region,under the same conditions.It is also compared with the T1 TSK FLS and IT2 TSK FLS methods with back propagation(BP)and particle swarm optimization(PSO)algorithms,as well as IT2 A2-C0 TSK FLS methods with EKF.The experimental results confirm that the proposed IT2 A2-C1 FLS method is superior to the other FLS methods regarding performance,which demonstrates its effectiveness and application potential.
基金supported in part by Sichuan Science and Technology Program under Grant No.2025ZNSFSC151in part by the Strategic Priority Research Program of Chinese Academy of Sciences under Grant No.XDA27030201+1 种基金the Natural Science Foundation of China under Grant No.U21B6001in part by the Natural Science Foundation of Tianjin under Grant No.24JCQNJC01930.
摘要The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysis of the proposed distributed KF algorithm without independent and stationary signal assumptions,which implies that the theoretical results are able to be applied to stochastic feedback systems.Note that the main difficulty of stability analysis lies in analyzing the properties of the product of non-independent and non-stationary random matrices involved in the error equation.We employ analysis techniques such as stochastic Lyapunov function,stability theory of stochastic systems,and algebraic graph theory to deal with the above issue.The stochastic spatio-temporal cooperative information condition shows the cooperative property of multiple sensors that even though any local sensor cannot track the time-varying unknown signal,the distributed KF algorithm can be utilized to finish the filtering task in a cooperative way.At last,we illustrate the property of the proposed distributed KF algorithm by a simulation example.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFB3305600)the National Natural Science Foundation of China(Grant Nos.61621003,62141604)+1 种基金the China Postdoctoral Science Foundation(Grant No.2022M722926)the Major Key Project of Peng Cheng Laboratory(Grant No.PCL2023AS1-2)。
摘要This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic systems.To deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)algorithm.Our algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional space.Subsequently,the original high-dimensional sparse signals can be well recovered by a reconstruction technique.To ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback systems.We further present the performance of the compressed KF algorithm.Specifically,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and optimized.Finally,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.
摘要Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcoming, Kalman filtering algorithm for this series is established,and its correctness and validity are verified with the test data obtained on the movable platform in plane. The results show that Kalman filtering can improve the correctness, reliability and stability of the deformation information series.
摘要[目的/意义]针对温室温湿度预测中多传感器数据融合可靠性低、传统模型忽略温湿度动态耦合,以及参数调优依赖人工经验等问题。[方法]首先,对传统卡尔曼(Kalman)滤波算法实施改进,通过动态调整过程噪声协方差和观测噪声协方差,结合新息方差动态分配多传感器权重。其次,针对温湿度的强耦合性及其协同控制的需求,构建多输出长短期记忆-注意力机制(Long Short-Term Memory-Attention,LSTM-Attention)模型,以温湿度协同预测为目标,引入注意力机制自适应加权关键环境因子,并采用灰狼优化算法(Grey Wolf Optimizer,GWO)自动对超参数进行寻优。[结果和讨论]提出的自适应卡尔曼滤波算法在多点温湿度融合中的平均绝对偏差分别为1.59℃和8.64%,比传统卡尔曼滤波算法分别降低1.24%、8.57%。以该算法融合结果作为模型训练集,模型在温湿度预测中决定系数R2分别达到98.2%和99.3%,比传统Kalman提升4.7%和4.3%。GWO-LSTM-Atten⁃tion模型的温湿度预测均方根误差分别为0.7768℃和2.0564%,比LSTM、LSTM-Attention时间序列预测模型分别降低15.6%、6.6%,湿度分别降低29.2%、5.7%。[结论]提出的自适应卡尔曼融合算法能够有效抑制异常值影响,可在非平稳环境变化下实现多传感器数据可靠融合。在温室多环境因子预测中,GWO-LSTM-Attention模型温湿度预测值在未来可作为控制温室环境的重要参考,进而实现对温室环境的实时调控。
基金supported by the National Natural Science Foundation of China (40701120)the Beijing Natural Science Foundation, China (4092016)the Beijing Nova, China (2008B33)
摘要Data assimilation in agricultural remote sensing research is of great significance to integrate with remote sensing observations and model simulations for parameters estimation. The present investigation not only designed and realized the Ensemble Kalman Filtering algorithm (EnKF) assimilation by combing the crop growth model (CERES-Wheat) with remote sensing data, but also optimized and updated the key parameters (LAI) of winter wheat by using remote sensing data. Results showed that the assimilation LAI and the observation ones agreed with each other, and the R2 reached 0.8315. So assimilation remote sensing and crop model could provide reference data for the agricultural production.
摘要The standalone Global Positioning System (GPS) does not meet the higher accuracy requirements needed for approach and landing phase of an aircraft. To meet the Category-I Precision Approach (CAT-I PA) requirements of civil aviation, satellite based augmentation system (SBAS) has been planned by various countries including USA, Europe, Japan and India. The Indian SBAS is named as GPS Aided Geo Augmented Navigation (GAGAN). The GAGAN network consists of several dual frequency GPS receivers located at various airports around the Indian subcontinent. The ionospheric delay, which is a function of the total electron content (TEC), is one of the main sources of error affecting GPS/SBAS accuracy. A dual frequency GPS receiver can be used to estimate the TEC. However, line-of-sight TEC derived from dual frequency GPS data is corrupted by the instrumental biases of the GPS receiver and satellites. The estimation of receiver instrumental bias is particularly important for obtaining accurate estimates of ionospheric delay. In this paper, two prominent techniques based on Kalman filter and Self-Calibration Of pseudo Range Error (SCORE) algorithm are used for estimation of instrumental biases. The estimated instrumental bias and TEC results for the GPS Aided Geo Augmented Navigation (GAGAN) station at Hyderabad (78.47°E, 17.45°N), India are presented.
摘要Because of the ignored items after linearization,the extended Kalman filter(EKF)becomes a form of suboptimal gradient descent algorithm.The emanative tendency exists in GPS solution when the filter equations are ill-posed.The deviation in the estimation cannot be avoided.Furthermore,the true solution may be lost in pseudorange positioning because the linearized pseudorange equations are partial solutions.To solve the above problems in GPS dynamic positioning by using EKF,a closed-form Kalman filter method called the two-stage algorithm is presented for the nonlinear algebraic solution of GPS dynamic positioning based on the global nonlinear least squares closed algorithm--Bancroft numerical algorithm of American.The method separates the spatial parts from temporal parts during processing the GPS filter problems,and solves the nonlinear GPS dynamic positioning,thus getting stable and reliable dynamic positioning solutions.
基金supported by the National Natural Science Foundation of China (No. 61573283)
摘要The fading factor exerts a significant role in the strong tracking idea. However, traditional fading factor introduction method hinders the accuracy and robustness advantages of current strong-tracking-based nonlinear filtering algorithms such as Cubature Kalman Filter(CKF) since traditional fading factor introduction method only considers the first-order Taylor expansion. To this end, a new fading factor idea is suggested and introduced into the strong tracking CKF method.The new fading factor introduction method expanded the number of fading factors from one to two with reselected introduction positions. The relationship between the two fading factors as well as the general calculation method can be derived based on Taylor expansion. Obvious superiority of the newly suggested fading factor introduction method is demonstrated according to different nonlinearity of the measurement function. Equivalent calculation method can also be established while applied to CKF. Theoretical analysis shows that the strong tracking CKF can extract the thirdorder term information from the residual and thus realize second-order accuracy. After optimizing the strong tracking algorithm process, a Fast Strong Tracking CKF(FSTCKF) is finally established. Two simulation examples show that the novel FSTCKF improves the robustness of traditional CKF while minimizing the algorithm time complexity under various conditions.
摘要针对无线传感器网络中基于接收信号强度指示(Received Signal Strength Indicator,RSSI)定位技术易受环境影响、定位精度较低的问题,提出一种将RSSI定位过程分为测距阶段与定位阶段的双阶段优化方法。测距阶段,改进卡尔曼滤波算法以RSSI信号均值作为初始状态估计,结合网格遍历搜索优化过程噪声协方差和测量噪声协方差参数,提升卡尔曼滤波算法的适应性和滤波效果,降低测距阶段的误差;定位阶段,使用多策略改进鲸鱼优化的节点位置估计算法求解未知节点位置,进一步提高定位精度。该算法通过K-means聚类初始化策略、精英反向学习策略和随机鲸鱼学习策略,提升原始鲸鱼优化算法的全局搜索能力和收敛速度,进一步提高定位精度。实验结果表明,该双阶段优化方法在定位误差控制方面优于传统的单阶段优化策略,具备更高的定位精度与更强的环境适应能力,并在与其他对比算法的性能比较中展现出明显优势。
摘要无迹卡尔曼滤波(unscented Kalman filter,UKF)是锂离子电池荷电状态(state of charge,SOC)估计的常用算法之一。然而在实际应用中,由于受到外界环境温度变化、电池容量退化等不确定性干扰,以及非高斯过程噪声的影响,需要进一步提高算法的性能才能更有效地保证估计精度。基于此,提出一种改进的无迹卡尔曼滤波算法(PO-RUKF)。首先,在UKF中引入H∞滤波提高算法的鲁棒性,用来克服各种干扰带来的不良影响。其次,利用鹦鹉优化算法对UKF的过程噪声协方差矩阵进行自适应调整,以解决滤波噪声参数先验确定的问题,从而提高滤波精度。最后,采用马里兰大学的FUDS和HPPC工况下的两种公开数据集进行了实验验证,结果表明,在不同的温度、电池容量退化状态以及不同的工况下,相比于传统的UKF算法以及鲁棒UKF算法,改进后的算法具有更高的SOC估计精度,平均绝对误差小于0.50%,均方根误差小于0.56%,此外还展现出更强的鲁棒性和普适性。证实所提方法可以为锂离子电池SOC估计提供更可靠、有效的技术支撑。