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Broadband control of plate radiation using a piezoelectric, double-amplifier active-skin and structural acoustic sensing

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JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2000年第2期107卷 876-884页

作者： Johnson, BD Fuller, CR Virginia Polytech Inst & State Univ Vibrat & Acoust Labs Dept Mech Engn Blacksburg VA 24061 USA

The potential of a piezoelectric, double-amplifier active-skin with structural acoustic sensing (SAS) is demonstrated for the reduction of broadband acoustic radiation from a clamped, aluminum plate. The active-skin is a continuous covering of the vibrating portions of the plate with active, independently controllable piezoelectric, double-amplifier elements and is designed to affect control by altering the continuous structural radiation impedance rather than structural vibration. In simulation, acoustic models are sought for the primary and secondary sources that incorporate finite element methods. Simulation indicates that a total radiated power attenuation in excess of 10 dB may be achieved between 250 and 750 Hz with microphone error sensing, while under SAS the radiated power is reduced by nearly 8 dB in the same frequency range. In experiment, the adaptive feed forward filtered-x LMS (least mean square) algorithm, implemented on a Texas Instruments C40 DSP, was used in conjunction with the 6I6O control system. With microphone error sensing, 11.8-dB attenuation was achieved in the overall radiated power between 175 and 600 Hz. while inclusion of SAS resulted in a 7.3-dB overall power reduction in this frequency band. (C) 2000 Acoustical Society of America. [S0001-4966(00)00702-5].

关键词： broadband Aluminum sheet Microphone Device Component Frequency bands structural vibration frequency ranges Synthetic aperture sonar Acoustic imagery power decay least mean square algorithm

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A Comparative Survey of Convex Combination of Adaptive Filters

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IETE JOURNAL OF RESEARCH 2023年第2期69卷 940-950页

作者： Vazquez, Angel A. Avalos, J. Gerardo Sanchez, Giovanny Sanchez, Juan C. Perez, Hector Inst Politecn Nacl Mexico City 04260 DF Mexico Inst Politecn Nacl Grad Studies & Res Sect ESIME Culhuacan Mexico City 04260 DF Mexico

Over the last twenty years, combination of adaptive filters has emerged to provide a potential solution in the development of advanced applications, such as channel equalization, active noise control, acoustic echo cancelation, adaptive beamforming, among others. Several authors have demonstrated that the combination of two filters with complementary capabilities improves the overall filter performance in comparison when a single filter is used. Commonly, these combinations employ a fast filter and slow filter to guarantee fast convergence speed and low steady-state mean square error (MSE), respectively, at the cost of increasing their computational complexity. However, those combinations have not been well analysed and compared. Currently, this aspect is crucial since most of the current convex combination of adaptive filters could be implemented in advanced embedded digital devices to be used in real-time signal processing applications. In this work, we evaluate the convex combination of adaptive filters, mainly including those based on least mean square (LMS) algorithm, the affine projection (AP) algorithm and the recursive least mean square (RLS) algorithm. We carry out an extensive performance evaluation to demonstrate the advantages and disadvantages of each approach. Specifically, we simulate them in fixed point, which makes feasible the rapid development of advanced prototypes. This aspect could be potentially valuable to the signal processing engineering communities.

关键词： Adaptive filters Adaptation term Affine projection algorithm Convex combination least mean square algorithm Recursive least mean square algorithm

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Use of Schroeder-phased waveform to investigate convergence and tracking of the LMS algorithm in active sound control

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APPLIED ACOUSTICS 1998年第1-3期53卷 95-116页

作者： Wright, AB Craig, KC Department of Applied Science University of Arkansas at Little Rock Little Rock AR 72204 USA Department of Mechanical Engineering Aeronautical Engineering and Mechanics Rensselaer Polytechnic Institute Troy NY 12180 USA

A Schroeder-phased test waveform is used to investigate convergence and tracking of the LMS system identification process in the filtered-X LMS active sound cancellation scheme. The coherence between the test waveform and the error microphone is calculated off-line. The power in the test waveform is increased until coherence between the two signals is achieved. The active sound cancellation algorithm is activated and the LMS system identification is adaptively modified on-line using different power in the test waveform. An error between the actual model, as determined by a Bode plot, and the LMS FIR model is calculated. When the power in the test waveform becomes large enough that coherence between the test signal and the error microphone is achieved, the model error decreases to a minimum. Further increase in test waveform power shows no further reduction in model error. It is also shown that when the part of the control signal which cancels sound is used in the on-line system identification algorithm, the model at the cancellation frequency degrades. This problem does not occur when only the test waveform is used in the system identification algorithm. Finally, it is shown, both analytically and experimentally, that the zeros in the FIR model emulate dynamic poles by spacing themselves uniformly around the unit circle in the z-plane. (C) 1997 Elsevier Science Ltd.

关键词： system identification active sound cancellation least mean square algorithm

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Optimization of automotive suspension system using vibration and noise control for intelligent transportation system

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SOFT COMPUTING 2023年第12期27卷 8315-8329页

作者： Li, Shisheng Yuan, Qiong Chongqing Automot Power Syst Testing Engn Technol Chongqing 401120 Peoples R China Chongqing Ind Polytech Coll Dept Vehicle Engn Chongqing 401120 Peoples R China

The objective of this work is to carry out a thorough investigation on the optimization of the vehicle suspension system based on vibration and noise management. First, a transfer path analysis is proposed to clarify the weight coefficient of vehicle's suspension system reaction optimization, resulting in an improved suspension system in reaction to optimization objective function to avoid the limitations of traditional vehicle suspension system's reaction optimization and ensure that the natural frequency and decoupling rate objectives will not deteriorated. To complete the optimization of the vehicle suspension system based on vibration and noise management, the variable step size algorithm is utilized to enhance the filtered least mean square method while at the same time, the adaptive algorithm is improved. The strategy put forward in this research has been shown to have a good effect on the optimization of the vehicle's suspension system through experimental verification. This method can effectively enhance the vehicle's overall comfort and stability while increasing operating safety. It is anticipated that it will serve as a valuable resource for future studies in this area.

关键词： Intelligent transportation system Vibration and noise control Automobile suspension system Variable step size algorithm least mean square algorithm Machine learning

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Enhanced-Convergence Normalized LMS algorithm

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IEEE SIGNAL PROCESSING MAGAZINE 2009年第3期26卷 81-+页

作者： Givens, Maurice Inst Gas Technol Chicago IL 60616 USA Wright Coll Chicago IL USA

Not Available

关键词： least mean square algorithm

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AN INEQUALITY BY WHICH TO ADJUST THE LMS algorithm STEP-SIZE

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IEEE TRANSACTIONS ON COMMUNICATIONS 1995年第2-4期43卷 1477-1483页

作者： CHEN, JN PRIEMER, R UNIV ILLINOIS DEPT ELECT ENGN & COMP SCICHICAGOIL 60680

This paper gives a method for differentiating between the transient and steady states in the LMS algorithm using inequalities among a set of output errors. Based on these inequalities, it also gives an algorithm for automatic step size adjustment to both improve the convergence rate and reduce steady-state parameter estimation errors.

关键词： step size steady-state parameter Steady state inequalities outlet error least mean square algorithm

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A new system identification method for fast echo canceler initialization

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IEEE TRANSACTIONS ON COMMUNICATIONS 1996年第2期44卷 137-142页

作者： Ahmed, SA Cruz, JR UNIV OKLAHOMA SCH ELECT ENGNNORMANOK 73019

We propose a new recursive version of an earlier technique for fast initialization of data-driven echo cancelers (DDEC's). The speed of convergence and the covariance of the estimate of the proposed technique are comparable to the recursive least squares (RLS) algorithm, however, the computational complexity is no greater than the least mean square (LMS) algorithm, Analysis of computational complexity and the estimation error is also provided. Simulation results based on both floating-point and fixed-point arithmetic illustrate a remarkable improvement in terms of speed of convergence and steady-state error over the computationally comparable LMS algorithm.

关键词： Echo cancellers Echoes System identification initialization complexity classes Fasting Covariance FLOATING POINTS Converge Simulation results Fixed-point arithmetic Comparable Identification methods least mean square algorithm

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A New Approach for Characterizing the Energetic Magnetic Behavior of Fe-9Cr Steel Under Transient Conditions

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IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 2012年第12期61卷 3273-3279页

作者： Marracci, Mirko Tellini, Bernardo Maione, Ivan Alessio Univ Pisa Dept Energy & Syst Engn I-56122 Pisa Italy Karlsruhe Inst Technol Inst Neutron Phys & Reactor Technol D-76344 Eggenstein Leopoldshafen Germany

The aim of this paper is to evaluate the magnetic properties and losses of the Fe-9Cr steel under nonperiodic conditions of the magnetic field. A new approach combining an optimized linear problem and the properties of the classical Preisach theory is adopted and described. An experimental analysis is carried out to characterize quasi-static major loop and dynamic cycles obtained at different rates of the driving magnetic field H. After a series of quasi-static major loops, dynamic cycles are defined in a first case, varying H from the saturation to its opposite value, and in a second case, forming minor asymmetric loops. In both the cases, hysteresis and eddy current losses are estimated via the proposed method. Total losses are compared with measurement results to validate the procedure.

关键词： Electromagnetic measurement least mean square algorithm loss measurement magnetic hysteresis magnetic materials

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PERFORMANCE ANALYSIS OF STRUCTURED GRADIENT algorithm

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 1990年第7期38卷 1078-1083页

作者： GODARA, LC Department of Electrical Engineering Australian Defence Force Academy University of New South Wales Campbell ACT Australia Information Systems Laboratory Department of Electrical Engineering University of Stanford Stanford CA USA

The structured gradient algorithm uses a structured estimate of the array correlation matrix to estimate the gradient required for the constrained least mean square algorithm. This structure reflects the structure of the exact array correlation matrix for an equispaced linear array and is obtained by spatial averaging of the elements of the noisy correlation matrix. In its standard form the LMS algorithm does not exploit the structure of the array correlation matrix. The gradient is estimated by multiplying the array output with the receiver outputs. An analysis of the two algorithms is presented to show that the covariance of the gradient estimated by the structured method is less sensitive to the look direction signal than that estimated by the standard method. The effect of the number of elements on the signal sensitivity of the two algorithms is studied.

关键词： algorithms Antenna arrays least mean square algorithm Gradient Covariance

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An improved anti-forensics JPEG compression using least Cuckoo Search algorithm

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IMAGING SCIENCE JOURNAL 2018年第3期66卷 169-183页

作者： Shelke, Priya M. Prasad, Rajesh S. Vishwakarma Inst Informat Technol Pune Maharashtra India STESs Sinhgad Inst Technol & Sci Pune Maharashtra India

The lossy nature of the JPEG compression leaves traces which are utilized by the forensic agents to identify the local tampering in the image. In this paper, a tricky anti-forensic method has been proposed to remove the traces left by the JPEG compression in both the spatial domain and discrete cosine transform domain. A novel least Cuckoo Search algorithm is devised in the proposed anti-forensic compression scheme. Moreover, a new fitness function called histogram deviation is formulated in the optimization algorithm. The experimentation of the proposed anti-forensic compression scheme is performed over uncompressed images from UCID database. The performance of the proposed method is evaluated, and it is compared with the existing methods using PSNR, MSE and classification accuracy as measures. The experimentation ensued with promising results, i.e. accuracy of 0.97, PSNR of 44.34dB, and MSE of 0.1789 which prove the efficacy of the proposed method.

关键词： JPEG anti-forensics JPEG compression least mean square algorithm Cuckoo Search optimization algorithm

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