Along with the increasing requests of the control level for power plant operation, accurate state parameters are needed for the advanced control, diagnosis and optimization algorithm. But the signal of the state param...
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Along with the increasing requests of the control level for power plant operation, accurate state parameters are needed for the advanced control, diagnosis and optimization algorithm. But the signal of the state parameter is obscured by all kinds of noises in thermal system and difficult to analyze. To solve this problem, a novel least-mean-square(lms) algorithm is used for characteristic extracting in the adaptive noise cancellation (ANC) problem. An improved lms algorithm based on Sigmoid function was presented. The simulation result shows that a superior performance of the new algorithm in stationary environment and an equivalent performance in nonstationary environment The experiment proves the method is effective and feasible for thermal processes signal analyzing.
Fast start-up in adaptive equalization is indispensable in communication systems that require on-line performance. In this article, a new type of adaptive linear FIR equalizer composed of two FIR filters and called th...
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Fast start-up in adaptive equalization is indispensable in communication systems that require on-line performance. In this article, a new type of adaptive linear FIR equalizer composed of two FIR filters and called the adaptive Butler-Cantoni (ABC) equalizer is proposed, and speed-up of convergence in the training mode is attempted. The ABC equalizer consists of a channel estimator and an equalization filter. The channel estimator updates coefficients by the lms algorithm. At the same time, the variance of the additive noise is computed. Based on these results, the coefficients of the equalization filter are successively derived by the Levinson-Trench algorithm, and the estimated value of the transmitted signal is computed. The computational complexity of the ABC equalizer is proportional to the square of the tap length but is not more than that of the RLS equalizer By computer simulation, it is demonstrated that the ABC equalizer provides better results than the lms and RLS equalizers. (C) 1999 Scripta Technica.
An adaptive filtering method is presented which eliminates ECG artifact from EMG signals based on error entropy criterion. In this method, the error distribution is estimated and minimized in an adaptive manner. Mean ...
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An adaptive filtering method is presented which eliminates ECG artifact from EMG signals based on error entropy criterion. In this method, the error distribution is estimated and minimized in an adaptive manner. Mean squared error (MSE) criterion only minimizes 2nd order statistics of the error, so it is sufficient in cases where inherent noise is Gaussian. The error entropy (EE) criterion, used in the proposed algorithm, minimizes all moments of error distribution. So in EMG denoising, where ECG artifact is typically non-Gaussian, Minimum Error Entropy (MEE)-based adaptive algorithm will improve noise elimination performance. Simulation results show that proposed algorithm has better spectral coherence in low frequencies and improves the SNR of the denoised EMG signal (about 5dB), especially in low SNR inputs, compared to MSE based algorithms.
based on the theoretical research of multi-channel active control, this article developed a four-channel dual-core controller based on DSP+FPGA, and achieved good control effects, through the four channels in double l...
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ISBN:
(纸本)9781510868755
based on the theoretical research of multi-channel active control, this article developed a four-channel dual-core controller based on DSP+FPGA, and achieved good control effects, through the four channels in double layer vibration isolation platform, under the test of lms system. According to the problems about slow convergence of speed in control systems, large delay in calculating of DSP caused by large amount of calculation, and not good reference signal, which are argued thoroughly, solutions were offered.
Performing distributed consensus in a network has been an important research problem for several years, and is directly applicable to sensor networks, autonomous vehicle formation, etc. While there exists a wide varie...
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ISBN:
(纸本)9781424442959
Performing distributed consensus in a network has been an important research problem for several years, and is directly applicable to sensor networks, autonomous vehicle formation, etc. While there exists a wide variety of algorithms that can be proven to asymptotically reach consensus, in applications involving time-varying parameters and tracking, it is often crucial to reach consensus "as quickly as possible". In [?] it has been shown that, with global knowledge of the network topology, it is possible to optimize the convergence time in distributed averaging algorithms via solving a semi-definite program (SDP) to obtain the optimal averaging weights. Unfortunately, in most applications, nodes do not have knowledge of the full network topology and cannot implement the required SDP in a distributed fashion. In this paper, we present a symmetric adaptive weight algorithm for distributed consensus averaging on bi-directional noiseless networks. The algorithm uses an lms (Least Mean Squares) approach to adaptively update the edge weights used to calculate each node's values. The derivation shows that global error can be minimized in a distributed fashion and that the resulting adaptive weights are symmetric--symmetry being critical for convergence to the true average. Simulations show that convergence time is nearly equal to that of a non-symmetric adaptive algorithm developed in [?], and significantly better than that of the non-adaptive Metropolis-Hastings algorithm. Most importantly, our symmetric adaptive algorithm converges to the sample mean, whereas the method of [?] converges to an arbitrary value and results in significant error.
A new adaptive scheme for system identification is proposed. The derivation of the algorithm and its convexity property are detailed. Also, the first moment behaviour as well as the second moment behaviour of the weig...
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A new adaptive scheme for system identification is proposed. The derivation of the algorithm and its convexity property are detailed. Also, the first moment behaviour as well as the second moment behaviour of the weights are studied. Bounds for the step size on the convergence of the proposed algorithm are derived, as well as the steady-state analysis is carried out. Finally, simulation results are performed and are found to corroborate with the theory developed.
IPMC is one kind of electro-active polymer materials,which is called artificial *** piezoelectric material,the creep property also exists in *** this paper we explained how the creep property created in IPMC, modified...
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IPMC is one kind of electro-active polymer materials,which is called artificial *** piezoelectric material,the creep property also exists in *** this paper we explained how the creep property created in IPMC, modified the creep model based on piezoelectric in order to get a creep model which fitted *** the creep property of IPMC changes with time,we applied adaptive inverse control to control IPMC,and got good experiment results.
The stack filter is the most systematic among the nonlinear filters, including the weighted median filter and the morphology filter. The authors undertook to expand the class of stack filters and to increase the numbe...
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The stack filter is the most systematic among the nonlinear filters, including the weighted median filter and the morphology filter. The authors undertook to expand the class of stack filters and to increase the number of degrees of freedom in the design. They employed a fuzzy Boolean function in which the output Boolean function takes a continuous value between "0" and "1" and proposed a fuzzy stack filter defined by that function. Up to the present, the fuzzy median filter and the fuzzy center weighted median filter have been presented as the most fundamental and simplest fuzzy stack filters. This paper proposes a fuzzy weighted median filter in which the weighted median filter, which isa more general nonlinear filter, is given a fuzzy property through the stack filter. The fuzzy weighted median filter changes continuously from the weighted median filter to the weighted average filter by varying the setting of the fuzzy Boolean function. This implies that the fuzzy weighted median filter has a high noise elimination ability for both impulsive and Gaussian noise. The fuzzy weighted median filter can be designed independently for the weight function and the fuzzy Boolean function. This paper aims at a simple design for the weight function and the fuzzy Boolean function, without losing its general character. The weight is approximated by an S-shaped function with only the distance from the processed point as the parameter, and the fuzzy Boolean function is approximated by a sigmoid function. The design is reduced to the determination of four parameters, which is performed by the lms algorithm. Through application examples, the properties and the effectiveness of the fuzzy weighted median filter are revealed. (C) 1999 Scripta Technica.
Tinnitus is a kind of auditory perception in the absence of external stimulus, its pathogenesis is not fully understood yet. Animal studies indicate that hearing loss through cochlear damage can lead to behavioral sig...
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Tinnitus is a kind of auditory perception in the absence of external stimulus, its pathogenesis is not fully understood yet. Animal studies indicate that hearing loss through cochlear damage can lead to behavioral signs of tinnitus, however its mechanism is still unclear. Sound therapy is one of the most effective treatments for tinnitus on clinic. In this paper, we proposed a novel adaptive model for tinnitus to expound the pathogenesis of tinnitus and the clinical effects of sound therapy. This model can maintain the signal intensity in central auditory system to a stable value by employing the Least Mean Square(lms) algorithm. When hearing loss occurs in this model, the central auditory system will adaptively magnify the auditory signals as well as the spontaneous signals. The significantly increased spontaneous signal is assumed to be tinnitus in this paper. Simulation results demonstrate that this model can not only explain the pathogenesis of tinnitus and the clinical effects of sound therapy, but also uncover the various curative corresponding to different external signals and the phenomenon of tinnitus relapse after the treatment of sound therapy.
In allusion to the multi-channel adaptive filtering feedforward control demand of structure vibration,this article focuses on the real-time identification method and experimental research of controlled channel in adap...
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In allusion to the multi-channel adaptive filtering feedforward control demand of structure vibration,this article focuses on the real-time identification method and experimental research of controlled channel in adaptive feedforward control, by taking flexible piezoelectric smart structure as test's model. Minimum square algorithm is used unified in real-time identification and control issues,also the channel model identification methods and the implementation of structural plans are given;A control system,including PC and monitoring template(including vc33dsp),is used in the controlled channel model's real-time identification;In this foundation,active vibration control test of piezoelectric smart structure is carried out,and the good results indicate that the controlled channel model's identification method is correct and feasible.
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