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A Robust GNSS Navigation Filter Based on Maximum Correntropy Criterion with Variational Bayesian for Adaptivity 被引量:1
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作者 Dah-Jing Jwo Yi Chang Ta-Shun Cho 《Computer Modeling in Engineering & Sciences》 2025年第3期2771-2789,共19页
In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenario... In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenarios with non-Gaussian noise and heavy-tailed outliers.The proposed design modifies the extended Kalman filter(EKF)for the global navigation satellite system(GNSS),integrating the maximum correntropy criterion(MCC)and the variational Bayesian(VB)method.This adaptive algorithm effectively reduces non-line-of-sight(NLOS)reception contamination and improves estimation accuracy,particularly in time-varying GNSS measurements.Experimental results show that the proposed method significantly outperforms conventional approaches in estimation accuracy under heavy-tailed outliers and non-Gaussian noise.By combining MCC with VB approximation for real-time noise covariance estimation using fixed-point iteration,the VBMCEKF achieves superior filtering performance in challenging GNSS conditions.The method’s adaptability and precision make it ideal for improving satellite navigation performance in stochastic environments. 展开更多
关键词 maximum correntropy criterion variational Bayesian extended Kalman filter GNSS
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The Maximum Effective Moment Criterion (MEMC) and Its Implications in Structural Geology 被引量:15
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作者 ZHENG Yadong WANG Tao WANG Xinshe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期70-78,共9页
The MohroCoulomb criterion has been widely used to explain formation of fractures. However, it fails to explain large strain deformation that widely occurs in nature. There is presently a new theory, the MEMC, which i... The MohroCoulomb criterion has been widely used to explain formation of fractures. However, it fails to explain large strain deformation that widely occurs in nature. There is presently a new theory, the MEMC, which is mathematically expressed as Meff = ((σ1-σ3) L.sin 2α sin α)/2, where σ1-σ3 represents the yield strength of the related rock, L is a unit length and a is the angle between σ1 and deformation bands. This criterion demonstrates that the maximum value appears at angles of ±54.7° to σ1 and there is a slight difference in the moment in the range of 55°±10°. The range covers the whole observations available from nature and experiments. Its major implications include: (1) it can be used to determine the stress state when the related deformation features formed; (2) it provides a new approach to determine the Wk of the related ductile shear zone if only the ratio of the vorticity and strain rate remains fixed; (3) It can be used to explain (a) the obtuse angle in the contraction direction of conjugate kink-bands and extensional crenulation cleavages, (b) formation of low-angle normal faults and high-angle reverse faults, (c) lozenge ductile shear zones in basement terranes, (d) some crocodile structures in seismic profiles and (e) detachment folds in foreland basins. 展开更多
关键词 maximum effective moment criterion crenulation cleavage low-angle normal fault high-angle reverse fault crocodile structure lozenge structure detachment fold
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On an Application of the Improved Maximum Product Criterion to Inverse Acoustic Scattering in a Layered Medium 被引量:1
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作者 Fermin S. Viloche Bazán Juliano de Bem Francisco +2 位作者 Koung Hee Leem George Pelekanos Vassilios Sevroglou 《Journal of Applied Mathematics and Physics》 2021年第4期661-682,共22页
In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well kn... In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well known <em>factorization method</em>, in which a computationally effective numerical scheme for the reconstruction of the shape of the scatterer is presented. This is possible, due to a <em>mixed reciprocity principle</em>, which renders the computation of the Green function at the background medium unnecessary. Moreover, to further refine our inversion algorithm, an efficient Tikhonov parameter choice technique, called <em>Improved Maximum Product Criterion</em> (IMPC) is exploited. Our regularization parameter is computed via a fast iterative algorithm which requires no <em>a priori</em> knowledge of the noise level in the far-field data. Finally, the effectiveness of IMPC is illustrated with various numerical examples. 展开更多
关键词 Acoustic Scattering Layered Medium Mixed Reciprocity Relation Factorization Method Improved maximum Product criterion (IMPC)
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Graphical method based on modified maximum force criterion to indicate forming limit curves of 22MnB5 boron steel sheets at elevated temperatures 被引量:1
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作者 Thanh Luyen Quoc-Tuan Pham +2 位作者 Thi-Bich Mac Tien-Long Banh Duc-Toan Nguyen 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2021年第8期1009-1018,共10页
A new approach for predicting forming limit curves(FLCs)at elevated temperatures was proposed herein.FLCs are often used to predict failure and determine the optimal forming parameters of automotive parts.First,a grap... A new approach for predicting forming limit curves(FLCs)at elevated temperatures was proposed herein.FLCs are often used to predict failure and determine the optimal forming parameters of automotive parts.First,a graphical method based on a modified maximum force criterion was applied to estimate the FLCs of 22MnB5 boron steel sheets at room temperature using various hardening laws.Subsequently,the predicted FLC data at room temperature were compared with corresponding data obtained from Nakazima's tests to obtain the best prediction.To estimate the FLC at elevated temperatures,tensile tests were conducted at various temperatures to determine the ratios of equivalent fracture strains between the corresponding elevated temperatures and room temperature.FLCs at elevated temperatures could be established based on obtained ratios.However,the predicted FLCs at elevated temperatures did not agree well with the corresponding FLC experimental data of Zhou et al.A new method was proposed herein to improve the prediction of FLCs at elevated temperatures.An FLC calculated at room tem-perature was utilized to predict the failure of Nakazima's samples via finite element simulation.Based on the simulation results at room temperature,the mathematical relationships between the equivalent ductile fracture strain versus stress triaxiality and strain ratio were established and then combined with ratios between elevated and room temperatures to calculate the FLCs at different temperatures.The predicted FLCs at elevated temperatures agree well with the corresponding experimental FLC data. 展开更多
关键词 Forming limit curve Modified maximum force criterion Graphical method Hardening law Finite element method Boron steel sheet Elevated temperature
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Maximum Correntropy Criterion-Based UKF for Loosely Coupling INS and UWB in Indoor Localization
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作者 Yan Wang You Lu +1 位作者 Yuqing Zhou Zhijian Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2673-2703,共31页
Indoor positioning is a key technology in today’s intelligent environments,and it plays a crucial role in many application areas.This paper proposed an unscented Kalman filter(UKF)based on the maximum correntropy cri... Indoor positioning is a key technology in today’s intelligent environments,and it plays a crucial role in many application areas.This paper proposed an unscented Kalman filter(UKF)based on the maximum correntropy criterion(MCC)instead of the minimummean square error criterion(MMSE).This innovative approach is applied to the loose coupling of the Inertial Navigation System(INS)and Ultra-Wideband(UWB).By introducing the maximum correntropy criterion,the MCCUKF algorithm dynamically adjusts the covariance matrices of the system noise and the measurement noise,thus enhancing its adaptability to diverse environmental localization requirements.Particularly in the presence of non-Gaussian noise,especially heavy-tailed noise,the MCCUKF exhibits superior accuracy and robustness compared to the traditional UKF.The method initially generates an estimate of the predicted state and covariance matrix through the unscented transform(UT)and then recharacterizes the measurement information using a nonlinear regression method at the cost of theMCC.Subsequently,the state and covariance matrices of the filter are updated by employing the unscented transformation on the measurement equations.Moreover,to mitigate the influence of non-line-of-sight(NLOS)errors positioning accuracy,this paper proposes a k-medoid clustering algorithm based on bisection k-means(Bikmeans).This algorithm preprocesses the UWB distance measurements to yield a more precise position estimation.Simulation results demonstrate that MCCUKF is robust to the uncertainty of UWB and realizes stable integration of INS and UWB systems. 展开更多
关键词 maximum correntropy criterion unscented Kalman filter inertial navigation system ULTRA-WIDEBAND bisecting kmeans clustering algorithm
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Multi-Kernel Bandwidth Based Maximum Correntropy Extended Kalman Filter for GPS Navigation
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作者 Amita Biswal Dah-Jing Jwo 《Computer Modeling in Engineering & Sciences》 2025年第7期927-944,共18页
The extended Kalman filter(EKF)is extensively applied in integrated navigation systems that combine the global navigation satellite system(GNSS)and strap-down inertial navigation system(SINS).However,the performance o... The extended Kalman filter(EKF)is extensively applied in integrated navigation systems that combine the global navigation satellite system(GNSS)and strap-down inertial navigation system(SINS).However,the performance of the EKF can be severely impacted by non-Gaussian noise and measurement noise uncertainties,making it difficult to achieve optimal GNSS/INS integration.Dealing with non-Gaussian noise remains a significant challenge in filter development today.Therefore,the maximum correntropy criterion(MCC)is utilized in EKFs to manage heavytailed measurement noise.However,its capability to handle non-Gaussian process noise and unknown disturbances remains largely unexplored.In this paper,we extend correntropy from using a single kernel to a multi-kernel approach.This leads to the development of a multi-kernel maximum correntropy extended Kalman filter(MKMC-EKF),which is designed to effectively manage multivariate non-Gaussian noise and disturbances.Further,theoretical analysis,including advanced stability proofs,can enhance understanding,while hybrid approaches integrating MKMC-EKF with particle filters may improve performance in nonlinear systems.The MKMC-EKF enhances estimation accuracy using a multi-kernel bandwidth approach.As bandwidth increases,the filter’s sensitivity to non-Gaussian features decreases,and its behavior progressively approximates that of the iterated EKF.The proposed approach for enhancing positioning in navigation is validated through performance evaluations,which demonstrate its practical applications in real-world systems like GPS navigation and measuring radar targets. 展开更多
关键词 Extended Kalman filter maximum correntropy criterion(MCC) multi-kernel maximum correntropy(MKMC) non-Gaussian noise
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Maximum Entropy Distribution Function and Uncertainty Evaluation Criteria 被引量:6
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作者 CHEN Bai-yu KOU Yi +3 位作者 ZHAO Daniel WU Fang WANG Li-ping LIU Gui-lin 《China Ocean Engineering》 SCIE EI CSCD 2021年第2期238-249,共12页
Marine environmental design parameter extrapolation has important applications in marine engineering and coastal disaster prevention.The distribution models used for environmental design parameter usually pass the hyp... Marine environmental design parameter extrapolation has important applications in marine engineering and coastal disaster prevention.The distribution models used for environmental design parameter usually pass the hypothesis tests in statistical analysis,but the calculation results of different distribution models often vary largely.In this paper,based on the information entropy,the overall uncertainty test criteria were studied for commonly used distributions including Gumbel,Weibull,and Pearson-III distribution.An improved method for parameter estimation of the maximum entropy distribution model is proposed on the basis of moment estimation.The study in this paper shows that the number of sample data and the degree of dispersion are proportional to the information entropy,and the overall uncertainty of the maximum entropy distribution model is minimal compared with other models. 展开更多
关键词 maximum entropy distribution model UNCERTAINTY information entropy evaluation criterion
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Maximum Correntropy Kalman Filtering for Non-Gaussian Systems With State Saturations and Stochastic Nonlinearities 被引量:4
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作者 Bo Shen Xuelin Wang Lei Zou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1223-1233,共11页
This paper tackles the maximum correntropy Kalman filtering problem for discrete time-varying non-Gaussian systems subject to state saturations and stochastic nonlinearities.The stochastic nonlinearities,which take th... This paper tackles the maximum correntropy Kalman filtering problem for discrete time-varying non-Gaussian systems subject to state saturations and stochastic nonlinearities.The stochastic nonlinearities,which take the form of statemultiplicative noises,are introduced in systems to describe the phenomenon of nonlinear disturbances.To resist non-Gaussian noises,we consider a new performance index called maximum correntropy criterion(MCC)which describes the similarity between two stochastic variables.To enhance the“robustness”of the kernel parameter selection on the resultant filtering performance,the Cauchy kernel function is adopted to calculate the corresponding correntropy.The goal of this paper is to design a Kalman-type filter for the underlying systems via maximizing the correntropy between the system state and its estimate.By taking advantage of an upper bound on the one-step prediction error covariance,a modified MCC-based performance index is constructed.Subsequently,with the assistance of a fixed-point theorem,the filter gain is obtained by maximizing the proposed cost function.In addition,a sufficient condition is deduced to ensure the uniqueness of the fixed point.Finally,the validity of the filtering method is tested by simulating a numerical example. 展开更多
关键词 Fixed-point theorem maximum correntropy criterion non-Gaussian noises state saturations stochastic nonlinearities
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SINS/GNSS integrated navigation system based on maximum versoria filter 被引量:7
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作者 Chunhui ZHAO Zhenyu YANG +2 位作者 Xiaoran CHENG Jinwen HU Xiaolei Hou 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第8期168-178,共11页
In the missile-borne Strapdown Inertial Navigation System/Global Navigation Satellite System(SINS/GNSS)integrated navigation system,due to the factors such as the high dynamics,the signal blocking by obstacles,the sig... In the missile-borne Strapdown Inertial Navigation System/Global Navigation Satellite System(SINS/GNSS)integrated navigation system,due to the factors such as the high dynamics,the signal blocking by obstacles,the signal intefereces,etc.,there always exist pulse interferences or measurement information interruptions in the satellite receiver,which make nonstationary measurement process.The traditional Kalman Filter(KF)can tackle the state estimation problem under Gaussian white noise,but its performance will be significantly reduced under nonGaussian noises.In order to deal with the non-Gaussian conditions in the actual missile-borne SINS/GNSS integrated navigation systems,a Maximum Versoria Criterion Extended Kalman Filter(MVC-EKF)algorithm is proposed based on the MVC and the idea of M-estimation,which assigns a smaller weight to the anomalous measurements so as to suppress the influence of anomalous measurements on the state estimation while maintaining a relatively low calculation cost.Finally,the integrated navigation simulation experiments prove the effectiveness and robustness of the proposed algorithm. 展开更多
关键词 Extended Kalman filter Gaussian kernel function maximum versoria criterion Missile-borne SINS/GNSS integrated systems
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Non-iterative Cauchy kernel-based maximum correntropy cubature Kalman filter for non-Gaussian systems 被引量:3
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作者 Aastha Dak Rahul Radhakrishnan 《Control Theory and Technology》 EI CSCD 2022年第4期465-474,共10页
This article addresses the nonlinear state estimation problem where the conventional Gaussian assumption is completely relaxed.Here,the uncertainties in process and measurements are assumed non-Gaussian,such that the ... This article addresses the nonlinear state estimation problem where the conventional Gaussian assumption is completely relaxed.Here,the uncertainties in process and measurements are assumed non-Gaussian,such that the maximum correntropy criterion(MCC)is chosen to replace the conventional minimum mean square error criterion.Furthermore,the MCC is realized using Gaussian as well as Cauchy kernels by defining an appropriate cost function.Simulation results demonstrate the superior estimation accuracy of the developed estimators for two nonlinear estimation problems. 展开更多
关键词 maximum correntropy criterion Cubature Kalman filter Non-Gaussian noise Cauchy kernel Gaussian kernel
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Maximum correntropy-based pseudolinear Kalman filter for passive bearings-only target tracking 被引量:1
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作者 Asfia Urooj Rahul Radhakrishnan 《Control Theory and Technology》 EI CSCD 2024年第2期269-281,共13页
This paper proposes a new approach for solving the bearings-only target tracking (BoT) problem by introducing a maximum correntropy criterion to the pseudolinear Kalman filter (PLKF). PLKF has been a popular choice fo... This paper proposes a new approach for solving the bearings-only target tracking (BoT) problem by introducing a maximum correntropy criterion to the pseudolinear Kalman filter (PLKF). PLKF has been a popular choice for solving BoT problems owing to the reduced computational complexity. However, the coupling between the measurement vector and pseudolinear noise causes bias in PLKF. To address this issue, a bias-compensated PLKF (BC-PLKF) under the assumption of Gaussian noise was formulated. However, this assumption may not be valid in most practical cases. Therefore, a bias-compensated PLKF with maximum correntropy criterion is introduced, resulting in two new filters: maximum correntropy pseudolinear Kalman filter (MC-PLKF) and maximum correntropy bias-compensated pseudolinear Kalman filter (MC-BC-PLKF). To demonstrate the performance of the proposed estimators, a comparative analysis assuming large outliers in the process and measurement model of 2D BoT is conducted. These large outliers are modeled as non-Gaussian noises with diverse noise distributions that combine Gaussian and Laplacian noises. The simulation results are validated using root mean square error (RMSE), average RMSE (ARMSE), percentage of track loss and bias norm. Compared to PLKF and BC-PLKF, all the proposed maximum correntropy-based filters (MC-PLKF and MC-BC-PLKF) performed with superior estimation accuracy. 展开更多
关键词 Bearings-only target tracking Pseudolinear Kalman filter maximum correntropy criterion Non-Gaussian noise
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Theoretical and Numerical Comparison of Limit Point Bifurcation and Maximum Force Criteria. Application to the Prediction of Diffuse Necking
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作者 Guillaume Altmeyer 《Modeling and Numerical Simulation of Material Science》 2013年第1期39-47,共9页
A large number of criteria has been developed to predict material instabilities, but their choice is limited by the lack of existing comparison of their theoretical basis and application domains. To overcome this limi... A large number of criteria has been developed to predict material instabilities, but their choice is limited by the lack of existing comparison of their theoretical basis and application domains. To overcome this limitation, a theoretical and numerical comparison of two major models used to predict diffuse necking is present in this paper. Limit Point Bifurcation criterion is first introduced. An original formulation of the Maximum Force Criterion (MFC), taking into account the effects of damage and isotropic and kinematic hardenings, is then proposed. Strong connections are shown between them by comparing their theoretical basis. Numerical Forming Limit Diagrams at diffuse necking obtained with these criteria for different metallic materials are given. They illustrate the theoretical link and similar predictions are shown for both models. 展开更多
关键词 FORMING BIFURCATION Analysis maximum FORCE criterion DIFFUSE NECKING FORMING Limit Diagram
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Maximum Likelihood Detection for Detect-and-Forward Relay Channels
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作者 Azlan Abd Aziz Yasunori Iwanami 《International Journal of Communications, Network and System Sciences》 2011年第2期88-97,共10页
This paper introduces a simple combining technique for cooperative relay scheme which is based on a Detect-and-Forward (DEF) relay protocol. Cooperative relay schemes have been introduced in earlier works but most of ... This paper introduces a simple combining technique for cooperative relay scheme which is based on a Detect-and-Forward (DEF) relay protocol. Cooperative relay schemes have been introduced in earlier works but most of them ignore the quality of the source-relay (S-R) channel in the detection at the destination, although this channel can contribute heavily to the performance of cooperation schemes. For optimal detection, the destination has to account all possible error events at the relay as well. Here we present a Maximum Likelihood criterion (ML) at the destination which considers closed-form expressions for each symbol error rate (SER) to facilitate the detection. Computer simulations show that significant diversity gain and Packet Error Rate (PER) performance can be achieved by the proposed scheme with good tolerance to propagation errors from noisy relays. In fact, diversity gain is increased with additional relay nodes. We compare this scheme against the baseline Cooperative-Maximum Ratio Combining (C-MRC). 展开更多
关键词 COOPERATIVE RELAY Detect-and-Forward maximum-LIKELIHOOD criterion Detection
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水库防洪优化调度SA-POA算法研究与应用 被引量:1
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作者 任明磊 张俊彬 +2 位作者 宁亚伟 刘昌军 张静 《中国防汛抗旱》 2025年第3期4-8,共5页
高精度的优化算法可提升水库防洪优化调度效果。针对传统的逐步优化算法(POA)易陷入局部最优的问题,在POA计算框架上引入模拟退火算法(SA),提出了一种SA-POA算法。该方法通过一定概率舍弃优化方向的最优解,使优化结果不易陷入局部最优,... 高精度的优化算法可提升水库防洪优化调度效果。针对传统的逐步优化算法(POA)易陷入局部最优的问题,在POA计算框架上引入模拟退火算法(SA),提出了一种SA-POA算法。该方法通过一定概率舍弃优化方向的最优解,使优化结果不易陷入局部最优,从而提升求解质量。为了进一步验证该方法的实用效果,以河北唐县西大洋水库“23·7”流域性特大洪水为例,使用传统的POA算法、粒子群优化算法(PSO)、SA-POA算法进行求解并和规程调度结果进行对比。研究显示,在最大削峰准则下,SA-POA算法比POA算法削峰率提高了6.5%;在最高水位最低化准则下,SA-POA算法的最高库水位比POA算法低0.5 m。两种准则下SA-POA算法均表现出较优的求解性能。 展开更多
关键词 水库防洪优化调度 SA-POA算法 最大削峰准则 改进算法 海河“23·7”流域性特大洪水
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采用广义混合最大相关熵准则扩展卡尔曼滤波算法的锂离子电池荷电状态估计
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作者 巫春玲 赵玉冰 +3 位作者 耿莉敏 徐先峰 王溢波 陈昊 《西安交通大学学报》 北大核心 2025年第7期159-169,共11页
为了解决非高斯噪声环境下荷电状态(SOC)估计不准确以及鲁棒性差等问题,提出一种基于广义混合最大相关熵准则的扩展卡尔曼滤波(GMMCC-EKF)算法。该算法利用两个广义高斯函数构成的核函数得到广义混合熵,继承了广义高斯核的灵活性,并通... 为了解决非高斯噪声环境下荷电状态(SOC)估计不准确以及鲁棒性差等问题,提出一种基于广义混合最大相关熵准则的扩展卡尔曼滤波(GMMCC-EKF)算法。该算法利用两个广义高斯函数构成的核函数得到广义混合熵,继承了广义高斯核的灵活性,并通过统计线性化技术将状态误差和测量误差统一纳入代价函数,进而通过固定点迭代法获得非线性方程的最优估计,然后将广义混合最大相关熵准则与扩展卡尔曼滤波相结合,增强在非高斯噪声环境下的稳定性,提高对复杂数据处理的准确性。为了验证算法有效性,分别选用两种不同类型的锂离子电池,在动态应力测试(DST)工况及多种环境温度(10、25和40℃)的新欧洲驾驶循环(NEDC)工况下对电池进行SOC估计。实验结果表明,在25℃且均匀混合噪声环境下,对于1号电池,GMMCC-EKF算法的估计精度相对于扩展卡尔曼滤波算法(EKF)和传统最大相关熵扩展卡尔曼滤波算法(MCC-EKF)分别提高了90.1%和83.9%;对于2号电池,估计精度分别提高了72.4%和47.4%,并且在10、40℃环境下该算法仍展现出最优性能。对1号、2号电池在25℃且拉普拉斯混合噪声环境下进行SOC估计,GMMCC-EKF算法相对于其他两种算法的估计精度也有显著提高。在给定初始值错误的情况下,GMMCC-EKF算法能够快速地收敛到真实值。所提算法具有较高的估计精度、良好的适应性和鲁棒性,可为非高斯噪声环境下的SOC估计提供有效解决方案。 展开更多
关键词 荷电状态估计 广义混合最大相关熵准则 扩展卡尔曼滤波 非高斯噪声
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基于MMFC的8011-O铝合金动态变形成形极限预测
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作者 李萍 张百顺 +3 位作者 汪洋 张池 祝梦臣 薛克敏 《塑性工程学报》 北大核心 2025年第2期121-129,共9页
为获取空调翅片高速冲压实际生产应变速率下的成形极限图,首先对8011-O铝合金薄板进行了不同应变速率下的拉伸试验;然后采用改进的最大力理论(MMFC),基于不同硬化模型、屈服准则与应变速率对8011-O铝合金成形极限图进行理论计算预测;最... 为获取空调翅片高速冲压实际生产应变速率下的成形极限图,首先对8011-O铝合金薄板进行了不同应变速率下的拉伸试验;然后采用改进的最大力理论(MMFC),基于不同硬化模型、屈服准则与应变速率对8011-O铝合金成形极限图进行理论计算预测;最后结合有限元模拟胀形试验结果与计算结果进行对比验证。结果表明:原始的最大力理论忽略了分散颈缩转向局部颈缩的转变期的影响,导致预测结果较为保守,采用MMFC理论更符合实际的变形过程。采用Swift-Voce硬化模型、Barlat89屈服准则可以获得较为准确的理论预测结果。随着应变速率增加,8011-O铝合金产生了增强增塑现象,有利于提升该合金的成形极限。采用MMFC理论模型获得了高应变速率下材料的成形极限图,为实际生产提供了一定的理论指导。 展开更多
关键词 8011-O铝合金 成形极限图 改进的最大力理论 动态成形
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基于MCC-PCKF的跟网型变流器时变虚拟惯量与状态估计
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作者 王渝红 王雪珂 +3 位作者 文玉玲 郑宗生 廖建权 刘咏玥 《电力系统自动化》 北大核心 2025年第13期103-112,共10页
新能源接入下,非同步机的惯量估计对于应对系统有功功率扰动、保障系统稳定运行具有重要意义。针对新能源虚拟惯量的时变特性,建立跟网型新能源非同步机动态惯量与状态估计模型,采用混沌多项式卡尔曼滤波(PCKF)算法对电力系统的惯量参... 新能源接入下,非同步机的惯量估计对于应对系统有功功率扰动、保障系统稳定运行具有重要意义。针对新能源虚拟惯量的时变特性,建立跟网型新能源非同步机动态惯量与状态估计模型,采用混沌多项式卡尔曼滤波(PCKF)算法对电力系统的惯量参数及状态进行联合估计。在此基础上,考虑到异常噪声环境下PCKF算法精度下降、鲁棒性差等问题,采用最大熵原则,引入新的代价函数捕捉高阶统计量,提出一种基于最大熵准则-混沌多项式卡尔曼滤波(MCC-PCKF)的新能源非同步机时变虚拟惯量估计方法,有效提高了估计方法的鲁棒性与精确性。为验证所提方法的性能,对改进的IEEE 39节点系统进行算例分析,并与PCKF方法进行对比,验证了所提MCC-PCKF算法在异常噪声环境下时变惯量估计的鲁棒性与精确性。 展开更多
关键词 跟网型变流器 虚拟惯量 惯量估计 状态估计 最大熵准则 混沌多项式卡尔曼滤波
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考虑残余应力和硬度影响的齿轮弯曲疲劳寿命预估 被引量:2
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作者 赵鹏博 陈勇 +4 位作者 尤晖 周兴云 李光鑫 武一民 刘祥环 《机械强度》 北大核心 2025年第2期53-60,共8页
为研究残余应力和硬度对齿轮弯曲疲劳性能的影响,以渗碳热处理20MnCrS5钢制齿轮为研究对象,进行复合小径喷丸强化处理,进而实现同一材料的齿轮具有不同硬度和残余应力状态。以最大主应变准则为基础,分别引入残余应力影响项以及残余应力... 为研究残余应力和硬度对齿轮弯曲疲劳性能的影响,以渗碳热处理20MnCrS5钢制齿轮为研究对象,进行复合小径喷丸强化处理,进而实现同一材料的齿轮具有不同硬度和残余应力状态。以最大主应变准则为基础,分别引入残余应力影响项以及残余应力-硬度耦合影响项建立疲劳寿命预测模型。通过喷丸齿轮弯曲疲劳试验确定最优残余应力影响系数和修正系数,对比两种模型的寿命预测精度;通过未喷丸齿轮弯曲疲劳试验验证模型的准确性。结果表明,当单一考虑残余应力影响时,残余应力影响系数最优值为0.09,模型可实现较高的寿命预测精度。同时考虑残余应力和硬度影响,修正系数最优值为0.04,模型具有更高的预测精度。 展开更多
关键词 20MnCrS5渗碳齿轮 弯曲疲劳 复合小径喷丸 寿命预估 最大主应变准则
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极地脉冲噪声环境下水声信道时延-多普勒参数估计方法
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作者 张哲铭 韩笑 +2 位作者 葛威 杨舒允 殷敬伟 《声学学报》 北大核心 2025年第5期1314-1326,共13页
针对极地脉冲噪声导致现有估计算法性能下降甚至失效的问题,提出了一种鲁棒的正交匹配追踪算法。首先,通过引入最大相关熵准则实现原子基的准确选择;其次,利用L 1范数重构损失函数,减轻脉冲噪声对于参数求解的影响。同时,采用基于分布... 针对极地脉冲噪声导致现有估计算法性能下降甚至失效的问题,提出了一种鲁棒的正交匹配追踪算法。首先,通过引入最大相关熵准则实现原子基的准确选择;其次,利用L 1范数重构损失函数,减轻脉冲噪声对于参数求解的影响。同时,采用基于分布式迭代优化策略的交替方向乘子法,高效地获取全局最优解。数值仿真和基于中国第九次北极科考冰下实测脉冲噪声数据处理结果表明,所提方法相较于经典算法有明显的性能提升,在脉冲噪声下具有更高的估计精度和更强的鲁棒性。 展开更多
关键词 时延–多普勒信道 参数估计 极地脉冲噪声 稀疏表示 最大相关熵准则
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融合最大似然-小波与ICEEMDAN的电磁炮加速度自适应解析与重构
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作者 赵永壮 孙传猛 +2 位作者 裴东兴 师浩伟 王宇 《电子测量与仪器学报》 北大核心 2025年第3期177-189,共13页
获取准确的弹丸加速度对评估电磁炮性能至关重要。然而,弹丸在膛内与出炮口受到迥异的环境因素影响,使得加速度信号在膛内与出炮口阶段具有不同的模态特征,导致常规的基于全局的非线性非平稳信号处理方法失效。因此,提出融合最大似然-... 获取准确的弹丸加速度对评估电磁炮性能至关重要。然而,弹丸在膛内与出炮口受到迥异的环境因素影响,使得加速度信号在膛内与出炮口阶段具有不同的模态特征,导致常规的基于全局的非线性非平稳信号处理方法失效。因此,提出融合最大似然-小波与改进完全自适应噪声集合经验模态分解的电磁炮加速度自适应解析与重构方法,以期获得准确的电磁炮加速度:首先,通过最大似然-小波自适应地寻找在各时间区域的模态差异,实现信号分区;其次,采用改进完全自适应噪声集合经验模态分解方法对分区信号进行自适应分解;最后,基于t检验提取有效模态分量进行信号重构,实现有效电磁炮加速度的准确提取。相关实验表明,均方根误差改进率均大于0,相关系数提高至0.6731,信噪比提高至3.8614,相较于常规的全局性处理方法,避免了部分区域过分解或分解不彻底的问题,实现了电磁炮加速度的准确提取。 展开更多
关键词 电磁炮弹丸加速度 数字信号处理 最大似然准则 小波变换 模态分解
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