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In this paper, we provide a tutorial for the applications of “game-theory-based extended H infinity filtering (EHIF)” approach to various problems in disciplines of signal processing. The algorithm of this filtering approach is similar to that of the extended Kalman filtering (EKF). Since its invention, the Kalman filtering approach has been successfully and widely employed for many problems in scientific and engineering fields, e.g. target tracking, satellite systems, control, communications, etc. Therefore, the H infinity filtering approach also can be applied to all these problems. One big difference of EHIF from the EKF approach is that we apply it with unknown noise statistics of the state and measurement. In this tutorial, we introduce this non-well-known approach in spite of its practical usefulness, by providing the step by step algorithm with example problems of a number of signal processing disciplines. We also show that EHIF can outperform other approaches including the EKF that need to know the noise statistics in their applications, in some scenarios. By the contribution of this tutorial, we look forward to easy, and disseminative applications of EHIF to problems where, particularly, the EKF or particle filter could have been applied if noise statistics were known. 相似文献
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Measurement on the structural,morphological, electrical and optical properties of PANI-CSA nanofilms
《Measurement》2016
Camphorsulfonic acid doped polyaniline (PANI-CSA) prepared by chemical oxidative polymerization is spin coated on glass plates with four different PANI:CSA weight ratios (1:1, 1:2, 1:4 and 1:8) and measurements on the structural and optical properties are done. Thickness of the films measured <100 nm are termed as nanofilms. Fourier transform infrared spectroscopy indicated the presence of dopant and an increase in degree of polymerization with increase in dopant ratio. X-ray diffraction studies revealed the change of amorphous nature of the film to crystalline nature with increase in CSA dopant ratio. Scanning electron microscopy showed the change of very smooth morphology of the film to rough root-like morphology with increase in CSA dopant ratio. Hall-effect analysis showed that the increase in CSA weight ratio appreciably increases the conductivity of PANI-CSA films due to increase in carrier concentration and it also represents the semiconductivity (P-type) nature in all the films. UV–visible absorption studies reveal the broadening of absorption spectrum in visible region with maximum CSA dopant ratio (1:8). Photoluminescence spectra of PANI-CSA films excited using 300 nm, revealed that the change in intensity and position of emission peaks are due to transition of semiconducting nature of the film to conducting nature with an increase in CSA dopant ratio from 1:1 to 1:8. 相似文献
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《Measurement》2016
It is well-known that stochastic resonance (SR) is mainly used for signal denoising and weak signal detection. In this paper, we firstly find the frequency range selection characteristic (filtering characteristic) of re-scaling frequency SR (RFSR) caused by the driving frequency limitation of bistable SR. It then follows that a novel approach to separate vibration components with different frequencies by iteratively using SR is explored. The frequencies of most vibration signals exceed the driving frequency limitation, thus by use of different frequency-scale ratios, the vibration signals with different frequency range can be extracted by RFSR. Firstly, a small frequency-scale ratio is used to obtain the vibration signal with a narrow frequency range, i.e. low frequency vibration. As the output of SR may have a phase lag, a simple phase-shift correction method is proposed to improve the accuracy of signal component separation. The phase-shift corrected signal of RFSR output is separated from the original vibration signal and the residue is treated as the new vibration signal. Then, increasing the frequency-scale ratio according to a searching algorithm, the vibration signal with higher frequency can be obtained by RFSR. Through this iterative process, several harmonic vibration components can be separated from the original noisy vibration signal. The proposed method, empirical mode decomposition (EMD) and Hilbert vibration decomposition (HVD) are respectively applied to analyzing a simulated vibration signal and extracting the fault feature of a rotor system. The contrastive results show that this proposed method has good frequency resolution and can successfully separate monocomponent harmonic signals from a strongly noisy multicomponent harmonic vibration signal while EMD and HVD cannot. 相似文献
4.
《Journal of the European Ceramic Society》2006,26(14):2861-2865
Terahertz (THz) transmissivity and infrared (IR) reflectivity spectra of orthorhombic microwave (MW) ceramics Bi(Nb1−xVx)O4 (0.002 < x < 0.032) were measured between 4 and 3000 cm−1 (0.09–90 THz) at room temperature. A well underdamped mode, presumably the ferroelectric soft mode, was observed at 25 cm−1. Complex permittivity spectra obtained from the fits to our data were extrapolated down to the MW range and compared with the dielectric data near 5 GHz. The linear extrapolation of dielectric losses from THz down to the MW range is in agreement with the experimental MW losses. Addition of 3.2% of vanadium reduces the sintering temperature to 850 °C and the dielectric properties (ɛ′ = 42.2, Q·f = 14,000 GHz, τf = +10 ppm/°C) remain at a level satisfactory for MW applications. Somewhat lower MW losses were observed in a sample sintered in the N2 atmosphere. 相似文献
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双质量硅微陀螺仪驱动模态测试 总被引:1,自引:1,他引:0
考虑双线振动双质量硅微陀螺仪环境适应性强且两个质量块的差动输出能够有效消除共模干扰的影响,提出了一种新型双质量陀螺仪。依据双质量硅微陀螺的结构和工作原理,对该陀螺的驱动模态进行了理论分析,并提出了简化的动力学方程。利用ANSYS有限元软件对陀螺的驱动模态进行了数值仿真,并对陀螺仪样品进行了电路测试。通过几种不同的加载方式,分别得到了相应的仿真和测试的幅频曲线,结果表明,仿真和实验结果与理论分析完全一致,且双边驱动方式要优于单边驱动方式,反向驱动方式可以使陀螺仪在工作模态运动。仿真和实验结果验证了双质量硅微陀螺的驱动模态特性。 相似文献
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Tong Cui Aiguo Song Juan Wu 《Frontiers of Electrical and Electronic Engineering in China》2009,4(1):78-82
This article addresses a largely open problem in haptic simulation and rendering: contact force and deformation modeling for
haptic simulation of a discrete globe mass-spring model, especially for global deformation. The mass-spring system is composed
of nodes connected with radially distributed springs. We tackle the problem using the theory of virtual work, and relations
between the virtual force and nodal displacements are analyzed to obtain elastic deformations. The global deformation is controlled
by the total nodal deformations based on a force equation at each node. The simulation results verify the efficiency of the
contact force and deformation model with reasonable realism.
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Translated from Journal of Southeast University (Natural Science Edition), 2007, 37(5): 849–852 [译自 : 东南大学学报 (自然科学版)] 相似文献
8.
为了使超声波传感器能在动态环境下定位,要求单超声波接收头能测量多个目标.首先分析了超声波发射头产生的超声波特点,据此推导出接收信号的波形表达式.其次根据接收信号特点,系统标定时用接收信号包络峰值的0.5倍作阈值,而测量时用小阈值,以防止距离信息丢失.最后用C8051F021单片机设计了单接收头多目标测距系统.在2目标与接收头距离之差大于30 cm以上时能较精确地测量出2个距离. 相似文献
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上肢康复机器人实时安全控制 总被引:2,自引:0,他引:2
针对上肢辅助康复机器人临床使用中的安全性和平稳性问题,提出基于模糊逻辑的实时在线安全监测控制方法.机器人对患肢进行康复训练时,患肢状态对控制效果会产生影响;通过设计智能安全监控模糊控制器(SSFC)改善系统运动平稳性以及突发情况下的安全性.首先提取相关运动特征评估受训患肢状态稳定情况,安全监控模糊控制器智能实现正常扰动情况下的控制期望力调节以及突发情况下的紧急响应.其次通过基于位置的阻抗控制策略实现患肢与机器人末端的柔顺性.实验结果验证了该控制方法能够有效地实现康复机器人的安全性和平稳性. 相似文献
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