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扩展卡尔曼滤波对时变参数追踪性能的影响研究 被引量:2
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作者 唐宏志 姜金辉 《南京航空航天大学学报》 CAS CSCD 北大核心 2022年第2期304-310,共7页
扩展卡尔曼滤波(Extended Kalman filter,EKF)理论由线性卡尔曼滤波理论发展而来。在结构的物理参数未知的情况下,扩展卡尔曼滤波理论将结构的物理参数与其状态向量组成增广状态向量,对增广状态向量进行识别,从而得到修正的结构参数。... 扩展卡尔曼滤波(Extended Kalman filter,EKF)理论由线性卡尔曼滤波理论发展而来。在结构的物理参数未知的情况下,扩展卡尔曼滤波理论将结构的物理参数与其状态向量组成增广状态向量,对增广状态向量进行识别,从而得到修正的结构参数。本文引入扩展卡尔曼滤波理论,对结构参数进行识别。为了验证该方法的有效性,引入1个时变参数三自由度系统作为仿真算例,分别探讨扩展卡尔曼滤波中的各项滤波参数(模型噪声的协方差矩阵Q,测量噪声的协方差矩阵R)对结构的时变参数追踪性能的影响。结果表明,合适的滤波参数能使得算法更迅速,准确地识别出结构中的时变参数变化趋势。还通过一个悬臂梁仿真算例,证明了即使在部分测点没有测量的情况下,EKF算法也能识别出结构参数。 展开更多
关键词 扩展卡尔曼滤波 结构时变参数 滤波参数 参数追踪性能 悬臂梁
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一种可变步长傅里叶分析器的统计特性分析 被引量:1
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作者 温良 黄博妍 +2 位作者 魏国 孙金玮 沈毅 《电子学报》 EI CAS CSCD 北大核心 2015年第9期1763-1769,共7页
可变步长最小均方(Variable step-size LMS,VSS-LMS)算法的傅里叶分析器在稳态误差、收敛速度及追踪能力方面具有优异性能,对其进行全面的统计特性分析具有重要意义.本文基于误差服从高斯分布等假设在平均及均方意义下,推导出描述系统... 可变步长最小均方(Variable step-size LMS,VSS-LMS)算法的傅里叶分析器在稳态误差、收敛速度及追踪能力方面具有优异性能,对其进行全面的统计特性分析具有重要意义.本文基于误差服从高斯分布等假设在平均及均方意义下,推导出描述系统动态特性的差分方程组,完成系统的动态数学建模,进而对系统进行稳态性能分析,给出系统稳态误差关于参考信号频率、系统参数和附加噪声的表达式,为系统应用中的参数选取提供有效指导.仿真表明,本文建立的统计模型与仿真结果具有一致性,验证了分析的有效性. 展开更多
关键词 自适应傅里叶分析器 可变步长最小均方算法 统计特性分析 追踪性能 收敛性
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拖拉机用装卸装置的设计与试验
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作者 张强 于路路 贾洪雷 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2012年第S1期108-112,共5页
以提高农业重量物装卸机械化程度为目的,试制了拖拉机用3自由度液压装卸装置,该装置比传统装载机增加了一个自由度。构建了由计算机控制电磁比例方向流量控制阀的控制系统。针对装置的运动方式进行了分析,并对液压驱动性能和末端装卸装... 以提高农业重量物装卸机械化程度为目的,试制了拖拉机用3自由度液压装卸装置,该装置比传统装载机增加了一个自由度。构建了由计算机控制电磁比例方向流量控制阀的控制系统。针对装置的运动方式进行了分析,并对液压驱动性能和末端装卸装置回转轴的轨迹追踪性能进行了试验研究。建立了电磁比例方向流量控制阀的输入电压与液压缸伸缩速度的线性模型,试验结果表明:控制系统能实现良好的轨迹追踪性能。 展开更多
关键词 农业工程 农业重量物 装卸装置 控制系统 轨迹追踪性能
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并联式液压系统节能位置控制器
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作者 胡万强 李耀辉 《许昌学院学报》 CAS 2018年第8期60-64,共5页
针对定压电液伺服系统工作时系统能量损失大等问题,设计了一种兼顾系统性能和减少能量损失的变压电液伺服系统控制器.首先对电液伺服系统被控模型进行动力学分析,得出其空间状态方程,对其进行线性化处理,然后设计了控制器并整定.试验结... 针对定压电液伺服系统工作时系统能量损失大等问题,设计了一种兼顾系统性能和减少能量损失的变压电液伺服系统控制器.首先对电液伺服系统被控模型进行动力学分析,得出其空间状态方程,对其进行线性化处理,然后设计了控制器并整定.试验结果证明:所设计控制器能很好地处理系统追踪性能和减少能量损失之间的矛盾关系,是一种比较贴近实际可行的控制方法. 展开更多
关键词 变压电液伺服系统 减小能量损失 系统追踪性能 控制器设计
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基于RBF-ADRC的高速列车速度控制算法 被引量:1
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作者 宋莉 郭伟 +1 位作者 李飞 刘乐钰 《中国安全科学学报》 CAS CSCD 北大核心 2022年第6期131-136,共6页
针对高速列车运行过程中的时变与非线性模型问题,提出一种基于径向基(RBF)神经网络(RBFNN)优化的高速列车速度自抗扰控制(ADRC)算法。首先,以单质点模型建立列车动力学方程;其次,将ADRC技术应用到列车上,以列车外干扰作为扩张部分,借助... 针对高速列车运行过程中的时变与非线性模型问题,提出一种基于径向基(RBF)神经网络(RBFNN)优化的高速列车速度自抗扰控制(ADRC)算法。首先,以单质点模型建立列车动力学方程;其次,将ADRC技术应用到列车上,以列车外干扰作为扩张部分,借助非线性误差反馈控制律实时观测和补偿系统扰动,设计基于RBFNN优化的ADRC控制器;然后,以CRH380型列车参数进行目标速度曲线仿真追踪,验证RBF-ADRC控制器追踪性能;最后,将设计的RBF-ADRC控制器与传统ADRC控制器在抗干扰性能和追踪误差方面进行比较。结果表明:基于RBF-ADRC的控制器抗干扰性能高于传统的ADRC控制,且追踪误差更小,适用于列车严格运行条件。 展开更多
关键词 高速列车 径向基(RBF)神经网络(RBFNN) 自抗扰控制(ADRC) 目标速度曲线 追踪性能
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Research on efficient edge-chasing deadlock detection/resolution for distributed systems
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作者 程欣 Jin Feng Yang Xiaozong 《High Technology Letters》 EI CAS 2006年第4期408-412,共5页
Numerous edge-chasing deadlock detection algonthms were developed lor the cycle detection in distributed systems, but their detections had the n steps speed limitation and n ( n- 1) overhead limitation to detect a c... Numerous edge-chasing deadlock detection algonthms were developed lor the cycle detection in distributed systems, but their detections had the n steps speed limitation and n ( n- 1) overhead limitation to detect a cycle of size n under the one-resource request model. Since fast deadlock detection is critical, this paper proposed a new algorithm to speed up the detection process. In our algorithm, when the running of a transaction node is blocked, the being requested resource nodes reply it with the waiting or being waited message simultaneously, so the blocked node knows both its predecessors and successors, which helps it detecting a cycle of size 2 directly and locally. For the cycle of size n ( n 〉 2), a special probe is produced which has the predecessors information of its originator, so the being detected nodes know their indirect predecessors and direct successors, and can detect the cycle within n - 2 steps. The proposed algorithm is formally proved to be correct by the invariant verification method. Performance evaluation shows that the message overhead of our detection is ( n^2 - n - 2)/2, hence both the detection speed and message cost of the proposed algorithm are better than that of the existing al gorithms. 展开更多
关键词 distributed systems fast deadlock detection PROBE performance evaluation
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Tracking, Obedience and Defense between Belgian Shepherd Malinois and German Shepherd Dog
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作者 Ivana Gardifinova Martina Helclova +1 位作者 Stanislav Korab Lenka Hradecka 《Journal of Life Sciences》 2013年第1期89-91,共3页
Dogs are used for centuries as people helpers. One of possible use is a sport and service. BSM (Belgian Shepherd Malinois) and GS (German shepherd) dogs are most used breeds like service dogs and also most represe... Dogs are used for centuries as people helpers. One of possible use is a sport and service. BSM (Belgian Shepherd Malinois) and GS (German shepherd) dogs are most used breeds like service dogs and also most represented at sports competitions. Our aim was to compare the results of these breeds in the World Cup of International tests of working dogs (in years 2003-2011), which is the peak of competitions. The authors evaluated results of German shepherd dog performance test and Belgian shepherd Malinois performance in disciplines such as tracking, obedience and defense. Belgian Shepherds achieved in all disciplines higher score than German shepherds. It was found out that Belgian shepherd Malinois get significant higher score in all disciplines (tracking, obedience and defense) than German shepherd. However, both of breeds are used successfully as service dogs. 展开更多
关键词 German shepherd dog Belgian shepherd Malinois performance test comparison.
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Analysis of noncommensurate sampling effects on the performance of PN code tracking loops 被引量:1
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作者 YANG Jian YANG YiKang +2 位作者 LI JiSheng LI HengNian YANG TianShe 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第6期893-905,共13页
Noncoherent early-late processing (NELP) code tracking loops are often implemented using digital hardware for digital global positioning system (GPS) receivers. Noncommensurate sampling technology is widely used b... Noncoherent early-late processing (NELP) code tracking loops are often implemented using digital hardware for digital global positioning system (GPS) receivers. Noncommensurate sampling technology is widely used because it is viewed as an effective solution to cope with the drawback of digital effects. However, the relationship between the sampling rate and auto-correlation function (ACF) is not adequately characterized by traditional analysis. The principles for selecting the sampling rate are still not apparent. In order to solve this problem, we first analyzed the effects of different sampling rates on ACF and obtained the analytical form of a discrete auto-correlation function (DACF) for a noncommensurate sampling rate. Based on the result, the relationship between the step variation in DACF and NELP parameters such as sampling rate, integration time, and correlator spacing was determined. The maximum step variation size of DACF was also determined. However, considering the actual situation, additional factors such as code Doppler shift, precorrelation filter, and thermal noise may degrade the step variation of DACE The relationship between the step variation and these factors was analyzed separately. An appropriate sampling rate and appropriate correlator spacing were proposed to achieve the typical accuracy of measurement. The numerical simulation verified the validity of the above theoretical analyses, and finally, the conclusions and design constraints for the digital GPS receiver are summarized. 展开更多
关键词 sampling rate code tracking loops heat dissipation GPS digital receiver
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Transient Performance Improvement in Tracking Control for a Class of Nonlinear Systems with Input Saturation 被引量:2
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作者 LU Tao LAN Weiyao LI Zhibin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2018年第1期200-214,共15页
This paper addresses the composite nonlinear feedback(CNF) control for a class of singleinput single-output nonlinear systems with input saturation to track a time varying reference target with good transient perfor... This paper addresses the composite nonlinear feedback(CNF) control for a class of singleinput single-output nonlinear systems with input saturation to track a time varying reference target with good transient performance. The CNF control law consists of a tracking control law and a performance compensator. The tracking control law is designed to drive the output of the system to track the time varying reference target rapidly, while the performance compensator is used to reduce the overshoot caused by the tracking control law. The stability of the closed-loop system is established. The design procedure and the improvement of transient performance of the closed-loop system are illustrated with a numerical example and the controlled Van del Pol oscillator. 展开更多
关键词 Composite nonlinear feedback input saturation nonlinear systems tracking control
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Performance analysis of two EM-based measurement bias estimation processes for tracking systems 被引量:2
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作者 Zhi-hua LU Meng-yao ZHU +1 位作者 Qing-wei YE Yu ZHOU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2018年第9期1151-1165,共15页
In target tracking, the measurements collected by sensors can be biased in some real scenarios, e.g., due to systematic error. To accurately estimate the target trajectory, it is essential that the measurement bias be... In target tracking, the measurements collected by sensors can be biased in some real scenarios, e.g., due to systematic error. To accurately estimate the target trajectory, it is essential that the measurement bias be identified in the first place. We investigate the iterative bias estimation process based on the expectation-maximization(EM)algorithm, for cases where sufficiently large numbers of measurements are at hand. With the assistance of extended Kalman filtering and smoothing, we derive two EM estimation processes to estimate the measurement bias which is formulated as a random variable in one state-space model and a constant value in another. More importantly,we theoretically derive the global convergence result of the EM-based measurement bias estimation and reveal the link between the two proposed EM estimation processes in the respective state-space models. It is found that the bias estimate in the second state-space model is more accurate and of less complexity. Furthermore, the EM-based iterative estimation converges faster in the second state-space model than in the first one. As a byproduct, the target trajectory can be simultaneously estimated with the measurement bias, after processing a batch of measurements.These results are confirmed by our simulations. 展开更多
关键词 Non-linear state-space model Measurement bias Extended Kalman filter Extended Kalman smoothing Expectation-maximization (EM) algorithm
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