Journal articles: 'Impulsive signal'

1

Logan, Gordon D., Russell J. Schachar, and Rosemary Tannock. "Impulsivity and Inhibitory Control." Psychological Science 8, no. 1 (January 1997): 60–64. http://dx.doi.org/10.1111/j.1467-9280.1997.tb00545.x.

Full text

Abstract:

We report an experiment testing the hypothesis that impulsive behavior reflects a deficit in the ability to inhibit prepotent responses Specifically, we examined whether impulsive people respond more slowly to signals to inhibit (stop signals) than non-impulsive people In this experiment, 136 undergraduate students completed an impulsivity questionnaire and then participated in a stop-signal experiment, in which they performed a choice reaction time (go) task and were asked to inhibit their responses to the go task when they heard a stop signal The delay between the go signal and the stop signal was determined by a tracking procedure designed to allow subjects to inhibit on 50% of the stop-signal trials Reaction time to the go signal did not vary with impulsivity, but estimated stop-signal reaction time was longer in more impulsive subjects, consistent with the hypothesis and consistent with results from populations with pathological problems with impulse control

APA, Harvard, Vancouver, ISO, and other styles

2

Pan, Jin Feng, and Yan Zhang. "The Denoising Method for Transient Speed Signal of Diesel Engine." Advanced Materials Research 291-294 (July 2011): 2081–84. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.2081.

Full text

Abstract:

A new denoising method for the diesel engine transient speed signal was proposed, especially for the signal seriously corrupted by impulsive noises. This method takes two steps. The first step is to do impulsive noise removing. An improved differential rank impulse detector was used to do impulsive noise detection in this paper. After the impulsive noise was detected, it was replaced by the median value of the window it was in. Then the second step low pass filtering is taking on. Experiments show that the proposed method could remove the noise of the acquired diesel transient speed signals effectively, the denoised signal could reflect the real working conditions of the diesel engine.

APA, Harvard, Vancouver, ISO, and other styles

3

Aijun, Hu, Lin Jianfeng, Sun Shangfei, and Xiang Ling. "A Novel Approach of Impulsive Signal Extraction for Early Fault Detection of Rolling Element Bearing." Shock and Vibration 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/9375491.

Full text

Abstract:

The fault signals of rolling element bearing are often characterized by the presence of periodic impulses, which are modulated high-frequency harmonic components. The features of early fault in rolling bearing are very weak, which are often masked by background noise. The impulsiveness of the vibration signal has affected the identification of characteristic frequency for the early fault detection of the bearing. In this paper, a novel approach based on morphological operators is presented for impulsive signal extraction of early fault in rolling element bearing. The combination Top-Hat (CTH) is proposed to extract the impulsive signal and enhance the impulsiveness of the bearing fault signal, and the envelope analysis is applied to reveal the fault-related signatures. The impulsive extraction performance of the proposed CTH is compared with that of finite impulse response filter (FIR) by analyzing the simulated bearing fault signals, and the result indicates that the CTH is more effective in extracting impulsive signals. The method is evaluated using real fault signals from defective bearings with early rolling element fault and early fault located on the outer race. The results show that the proposed method is able to enhance the impulsiveness of early bearing fault signals.

APA, Harvard, Vancouver, ISO, and other styles

4

BARRABÈS, C., and P. A. HOGAN. "IMPULSIVE LIGHT-LIKE SIGNALS." International Journal of Modern Physics A 17, no. 20 (August 10, 2002): 2746. http://dx.doi.org/10.1142/s0217751x02011734.

Full text

Abstract:

A general characterisation of an impulsive light–like signal was given1,2. The signal may consist of a shell of null matter and/or an impulsive gravitational wave. Both parts of the signal can be unambiguously identified3,4. The signals can be used to model bursts of gravitational radiation and light– like matter accompanying cataclysmic events such as supernovae and neutron star collisions. Also in high speed collisions of compact objects such as black–holes or neutron stars the gravitational fields of these objects resemble those of impulsive light–like signals when the objects are boosted to the speed of light. Several examples of impulsive light–like signals were presented, in particular those produced by recoil effects5 and by the Aichelburg–Sexl boost of an isolated gravitating multipole source6. The detection of these signals was also discussed7.

APA, Harvard, Vancouver, ISO, and other styles

5

Lee, Sang Kwon, and Jung Soo Lee. "Design of Adaptive Filter for Health Monitoring on a Gearbox." Key Engineering Materials 321-323 (October 2006): 1237–40. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.1237.

Full text

Abstract:

Impulsive vibration signals in gearbox are often associated with faults, which lead to due to irregular impacting. Thus these impulsive vibration signals can be used as indicators of machinery faults. However it is often difficult to make objective measurement of impulsive signals because of background noise signals. In order to ease the measurement of impulsive signal embedded in background noise, we enhance the impulsive signals using adaptive signal processing and then analyze them in time and frequency domain by using time-frequency representation. This technique is applied to the diagnosis of faults within laboratory gearbox.

APA, Harvard, Vancouver, ISO, and other styles

6

Van, Mien, Pasquale Franciosa, and Dariusz Ceglarek. "Rolling Element Bearing Fault Diagnosis Using Integrated Nonlocal Means Denoising with Modified Morphology Filter Operators." Mathematical Problems in Engineering 2016 (2016): 1–14. http://dx.doi.org/10.1155/2016/9657285.

Full text

Abstract:

The impulses in vibration signals are used to identify faults in the bearings of rotating machinery. However, vibration signals are usually contaminated by noise that makes the process of extracting impulse characteristic of localized defect very challenging. In order to effectively diagnose bearing with noise masking vibration signal, a new methodology is proposed using integrated (i) nonlocal means- (NLM-) based denoising and (ii) improved morphological filter operators. NLM based denoising is first employed to eliminate or reduce the background noise with minimal signal distortion. This denoised signal is then analysed by a proposed modified morphological analysis (MMA). The MMA analysis introduces a new morphological operator which is based on Modified-Different (DIF) filter to include only fault relevant impulsive characteristics of the vibration signal. To improve further performance of the methodology the length of the structure element (SE) used in MMA is optimized using a particle swarm optimization- (PSO-) based kurtosis criterion. The results of simulated and real vibration signal show that the integrated NLM with MMA method as well as the MMA method alone yields superior performance in extracting impulsive characteristics of vibrations signals, especially for signal with high level of noise or presence of other sources masking the fault.

APA, Harvard, Vancouver, ISO, and other styles

7

Xu, Xiaojing, Yansheng Liu, Haitao Li, and Fuad E. Alsaadi. "Synchronization of switched Boolean networks with impulsive effects." International Journal of Biomathematics 11, no. 06 (August 2018): 1850080. http://dx.doi.org/10.1142/s1793524518500808.

Full text

Abstract:

This paper studies the state/output synchronization of switched Boolean networks (SBNs) with impulsive effects via the algebraic state space representation (ASSR) approach. First, an algebraic form is established for SBNs with impulsive effects via ASSR. Second, based on the algebraic form, some necessary and sufficient conditions are presented for the state/output synchronization of SBNs with impulsive effects under arbitrary switching signals. Third, two special kinds of switching signals, that is, free switching signal and feedback switching signal, are considered for the state synchronization of SBNs with impulsive effects. Finally, two illustrative examples are worked out to show the effectiveness of the obtained results.

APA, Harvard, Vancouver, ISO, and other styles

8

Ahadiat, Mohammad Reza, Paeiz Azmi, and Afrooz Haghbin. "The Mitigation of the Effect of Impulsive Noise in OFDM-PLC Systems." Journal of Research in Science, Engineering and Technology 3, no. 01 (September 13, 2019): 18–25. http://dx.doi.org/10.24200/jrset.vol3iss01pp18-25.

Full text

Abstract:

This paper proposes an new iterative method to recover the signals corrupted by impulsive noise in MIMO-OFDM systems over In-home PLC. In this iterative technique, preliminary decisions are made to get the impulsive noise detection algorithm for finding the locations and amplitudes of the impulses, and then signal estimation block for approximation the signals for two-branch 2*2 MIMO-OFDM at the receiver. In each iteration, this signals approximation are used to improve the noise estimate. After impulsive noise detection, an comparison - decision algorithm is employed to compare two noises estimated, and algorithm. This method use an adaptive threshold and soft decision to estimating and canceling the impulsive noises. Then, by using ML detection, an approximation of signal is obtained. As this impulsive noise detection , comparison - decision and ML detection loop continues, we get better approximates of the signal. The algorithm is analyzed and verified by computer simulations. A comparison between the performance of the different systems is presented and discussed. The Simulation results confirm the robustness of performance of the proposed algorithm.

APA, Harvard, Vancouver, ISO, and other styles

9

Li, Guo Jun, Xiao Na Zhou, Nai Qian Liu, and Shao Hua Li. "Robust Tracking Time-Varying High-Frequency CW Telegraph Signal." Applied Mechanics and Materials 155-156 (February 2012): 435–39. http://dx.doi.org/10.4028/www.scientific.net/amm.155-156.435.

Full text

Abstract:

Continuous wave (CW) telegraph is a crucial communication means for high-frequency tactical communication. But there is serious frequency deviation and impulsive noise in High-frequency channel, thus the conventional tracking method based on Gaussian noise assumption may lose the track of time-varying CW signal. A new robust kalman filter-based tracker is proposed in this paper to extract the time-varying CW signal in presence of impulsive interference, which uses a nonlinear statistical model. Simulation studies show this method can dynamically track nonstationary CW signal and effectively suppress burst impulse noise.

APA, Harvard, Vancouver, ISO, and other styles

10

Mohanty, Mihir Narayan, and Sarthak Panda. "Impulsive Noise Cancellation from ECG Signal using Adaptive Filters and their Comparison." Indonesian Journal of Electrical Engineering and Computer Science 3, no. 2 (August 1, 2016): 369. http://dx.doi.org/10.11591/ijeecs.v3.i2.pp369-376.

Full text

Abstract:

<em>Impulsive Noise is the sudden burst noise of short duration. Mostly it causes by electronic devices and electrosurgical noise in biomedical signals at the time of acquisition. In this work, Electrocardiograph (ECG) signal is considered and tried to remove impulsive noise from it. Impulsive noise in ECG signal is random type of noise. The objective of this work is to remove the noise using different adaptive algorithms and comparison is made among those algorithms. Initially the impulsive noise in sinusoidal signal is synthesized and tested for different algorithms like LMS, NLMS, RLS and SSRLS. Further those algorithms are modified in a new way to weight variation. The proposed novel approach is applied in the corrupted ECG signal to remove the noise. The effectiveness of the proposed approach is verified for ECG signal with impulsive noise as compared to the traditional approaches as well as previously proposed approaches. Also the performance of our approach is validated by SNR computation. Significant improvement in SNR is achieved after removal of noise.</em>

APA, Harvard, Vancouver, ISO, and other styles

11

Zhang, Haibin, Yuan Zheng, and Fanrang Kong. "Weak impulsive signals detection based on step-varying asymmetric stochastic resonance." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, no. 2 (August 9, 2016): 242–62. http://dx.doi.org/10.1177/0954406216631374.

Full text

Abstract:

Rotating machinery response is often characterized by the presence of periodic impulses modulated by high-frequency components. The fault information is often hidden in its envelope signal which is unilateral when demodulated. Conventional stochastic resonance with a symmetric potential cannot always contain the signal’s original features especially the asymmetry. In this article, a step-varying asymmetric stochastic resonance system for impulsive signal denoising and recovery as well as the rotating machine fault diagnosis is proposed to further improve the impulsive signal-to-noise ratio. In the method, the asymmetry of step-varying asymmetric stochastic resonance can match the unilateral impulsive signal well to generate an optimal dynamic system by selecting proper system parameters and degree of asymmetry. Systems with different simulated or experimental signals are also studied to verify its effectiveness and availability. Results indicate that the step-varying asymmetric stochastic resonance performs much better in detection of impulsive signal than the conventional stochastic resonance with merits of good frequency response, anti-noise capability, adaptability to asymmetric signal and original waveform preserving.

APA, Harvard, Vancouver, ISO, and other styles

12

Zhu, Yanli, and Yuangong Sun. "Stabilization of Discrete-Time Planar Switched Linear Systems with Impulse." Discrete Dynamics in Nature and Society 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/134296.

Full text

Abstract:

We study the stabilization problem of discrete-time planar switched linear systems with impulse. When all subsystems are controllable, based on an explicit estimation on the state transition matrix, we establish a sufficient condition such that the switched impulsive system is stabilizable under arbitrary switching signal with given switching frequency. When there exists at least one uncontrollable subsystem, a sufficient condition is also given to guarantee the stabilization of the switched impulsive system under appropriate switching signal.

APA, Harvard, Vancouver, ISO, and other styles

13

Hwang, Sung Wook, Jin Hyuk Han, Ki Duck Sung, and Sang Kwon Lee. "The Study of Tire Pattern Noise by Using Wavelet Transform." Applied Mechanics and Materials 105-107 (September 2011): 267–70. http://dx.doi.org/10.4028/www.scientific.net/amm.105-107.267.

Full text

Abstract:

Tire noise is classified by pattern noise and road noise in a vehicle. Especially pattern noise has impulsive characteristics since it is generated by impacting of tire’s block on the road. Therefore, a special signal process is needed other than traditional Fourier Transform, because the characteristic of signal is varying with time. On the other hand, the pattern noise is a kind of non-stationary signal and is related to the impulsive train of pitch sequence of a block. In this paper, Wavelet Transform is applied to verify the impulse signal caused by impact of block and groove and to verify the relationship between the pattern noise and the train of pitch sequence.

APA, Harvard, Vancouver, ISO, and other styles

14

Bae, Bum Won, In Pil Kang, and Yeon Sun Choi. "A Gear Chain Fault Detection Method Using an Adaptive Interference Canceling." Key Engineering Materials 345-346 (August 2007): 1303–6. http://dx.doi.org/10.4028/www.scientific.net/kem.345-346.1303.

Full text

Abstract:

A fault diagnosis method based on wavelet and adaptive interference canceling is presented for the identification of a damaged gear tooth. A damaged tooth of a certain gear chain generates impulsive signals that could be informative to fault detections. Many publications are available not only for the impulsive vibration signal analysis but the application of signal processing techniques to the impulsive signal detections. However, most of the studies about the gear fault detection using the impulsive vibration signals of a driving gear chain are limited to the verification of damage existence on a gear pair. Requirements for more advanced method locating damaged tooth in a driving gear chain should be a motivation of further studies. In this work an adaptive interference canceling combined with wavelet method is used for a successful identification of the damaged tooth location. An application of the wavelet technique provides a superior resolution for the damage detection to the traditional frequency spectrum based methods. An analysis and experiment with three pair gear chain show the feasibility of this study yielding a precise location of the damaged gear tooth.

APA, Harvard, Vancouver, ISO, and other styles

15

Bao, Xing Xian, and Cui Lin Li. "A Method of Signal-Noise Separation from Measured Vibration Response Signals." Advanced Materials Research 199-200 (February 2011): 909–12. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.909.

Full text

Abstract:

Measured vibration response signals are inevitably contaminated with noise originating from test environment as well as electronic devices. This situation often leads to serious difficulties in many applications as they require high-quality measured data. This paper presents a signal-noise separation method for measured impulsive response functions (IRFs) based on structured low rank approximation (SLRA). The proposed method was tested with a steel cantilever beam, which was subjected to impulsive excitation. Gabor transform was also employed to process measured signals. The results show that this method can give a reliable separation of signal and noise, which will enhance the accuracy of various applications that rely on measured signals.

APA, Harvard, Vancouver, ISO, and other styles

16

Bedicks, G., C. E. S. Dantas, F. Sukys, F. Yamada, L. T. M. Raunheitte, and C. Akamine. "Digital Signal Disturbed by Impulsive Noise." IEEE Transactions on Broadcasting 51, no. 3 (September 2005): 322–28. http://dx.doi.org/10.1109/tbc.2005.851139.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Peng, Zhijun, Yang Li, Xiaofeng Liao, and Chuandong Li. "Impulsive Synchronization of Lü Chaotic System Based on Small Impulsive Signal." International Journal of Theoretical Physics 47, no. 3 (August 29, 2007): 797–804. http://dx.doi.org/10.1007/s10773-007-9503-2.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Meng, Qing Hai. "Impulsive Noise Detection and Elimination Method for GPS Measurement Data." Applied Mechanics and Materials 556-562 (May 2014): 2783–86. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.2783.

Full text

Abstract:

For GPS measurement signal in aircraft experiment is often affected by transmission environment, and interfered with impulsive noise, hereby a SVD combined with wavelet neural network to detect and eliminate the impulsive noise method was proposed. The received GPS data is decomposed by SVD, and the decomposed component is acted as the input of wavelet neural network. Letts criterion is adopted to detect the impulsive noise according to the output residue error of the wavelet neural network. For the detection of the interference points of impulse noise, it can use wavelet network output to replace the measured value, so as to eliminate impulsive noise.

APA, Harvard, Vancouver, ISO, and other styles

19

Rodriguez, P. Dennis, and Gordon C. Baylis. "Activation of Brain Attention Systems in Individuals with Symptoms of ADHD." Behavioural Neurology 18, no. 2 (2007): 115–30. http://dx.doi.org/10.1155/2007/865717.

Full text

Abstract:

Previous research investigating attention and impulse control in individuals with Attention-Deficit/Hyperactivity Disorder (ADHD) has largely ignored the symptomatic differences among the three subtypes of ADHD: ADHD-Inattentive Type, ADHD-Hyperactive/Impulsive Type, and ADHD-Combined Type. The present study examined attention and impulse control by focusing on these subtypes. Based on their self-reported symptoms of ADHD, participants belonged to one of four groups: ADHD-Inattentive, ADHD-Hyperactive/Impulsive, ADHD-Combined, and control. Cortical activity was recorded from participants during performance of a Go/NoGo task. The event-related potentials (ERP) measured at frontal and posterior sites discriminated between the control group and participants with symptoms of ADHD. The control group consistently exhibited a higher P3 amplitude than all the ADHD groups. The main difference occurred at the frontal site, indicating that individuals with ADHD symptoms have deficits in the anterior attentional system, which mediates signal detection. Behavioral measures of signal sensitivity revealed that the ADHD-Inattentive and the ADHD-Hyperactive/Impulsive groups had more difficulty with the attention-demanding Go/NoGo respond-to-target task, while behavioral measures of response bias indicated that the ADHD-Hyperactive/Impulsive and the ADHD-Combined groups responded more liberally in the inhibition-demanding Go/NoGo suppress-to-target task.

APA, Harvard, Vancouver, ISO, and other styles

20

Ma, Jitong, Jiacheng Zhang, Zhengyan Yang, and Tianshuang Qiu. "Off-Grid DOA Estimation Using Sparse Bayesian Learning for MIMO Radar under Impulsive Noise." Sensors 22, no. 16 (August 20, 2022): 6268. http://dx.doi.org/10.3390/s22166268.

Full text

Abstract:

Direction of arrival (DOA) estimation is an essential and fundamental part of array signal processing, which has been widely used in radio monitoring, autonomous driving of vehicles, intelligent navigation, etc. However, it remains a challenge to accurately estimate DOA for multiple-input multiple-output (MIMO) radar in impulsive noise environments. To address this problem, an off-grid DOA estimation method for monostatic MIMO radar is proposed to deal with non-circular signals under impulsive noise. In the proposed method, firstly, based on the property of non-circular signal and array structure, a virtual array output was built and a real-valued sparse representation for the signal model was constructed. Then, an off-grid sparse Bayesian learning (SBL) framework is proposed and further applied to the virtual array to construct novel off-grid sparse model. Finally, off-grid DOA estimation was realized through the solution of the sparse reconstruction with high accuracy even in impulsive noise. Numerous simulations were performed to compare the algorithm with existing methods. Simulation results verify that the proposed off-grid DOA method enables evident performance improvement in terms of accuracy and robustness compared with other works on impulsive noise.

APA, Harvard, Vancouver, ISO, and other styles

21

Wang, Wenyuan, and Qiang Sun. "Robust Adaptive Estimation of Graph Signals Based on Welsch Loss." Symmetry 14, no. 2 (February 21, 2022): 426. http://dx.doi.org/10.3390/sym14020426.

Full text

Abstract:

This paper considers the problem of adaptive estimation of graph signals under the impulsive noise environment. The existing least mean squares (LMS) approach suffers from severe performance degradation under an impulsive environment that widely occurs in various practical applications. We present a novel adaptive estimation over graphs based on Welsch loss (WL-G) to handle the problems related to impulsive interference. The proposed WL-G algorithm can efficiently reconstruct graph signals from the observations with impulsive noises by formulating the reconstruction problem as an optimization based on Welsch loss. An analysis on the performance of the WL-G is presented to develop effective sampling strategies for graph signals. A novel graph sampling approach is also proposed and used in conjunction with the WL-G to tackle the time-varying case. The performance advantages of the proposed WL-G over the existing LMS regarding graph signal reconstruction under impulsive noise environment are demonstrated.

APA, Harvard, Vancouver, ISO, and other styles

22

Kim, Namyong, Hyung-Gi Byun, Young-Hwan You, and Kihyeon Kwon. "Blind signal processing for impulsive noise channels." Journal of Communications and Networks 14, no. 1 (February 2012): 27–33. http://dx.doi.org/10.1109/jcn.2012.6184548.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Flamme, Gregory, William J. Murphy, Chucri A. Kardous, and David C. Byrne. "Impulsive exposures from ceremonial and signal cannons." Journal of the Acoustical Society of America 145, no. 3 (March 2019): 1815. http://dx.doi.org/10.1121/1.5101634.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Nuawi, Mohd Zaki, Abdul Rahim Bahari, Shahrum Abdullah, and Ahmad Kamal Ariffin. "Comparison of Young's Modulus Property Determination of Metallic Materials under Two Statistical Analysis Methods." Advanced Materials Research 894 (February 2014): 186–91. http://dx.doi.org/10.4028/www.scientific.net/amr.894.186.

Full text

Abstract:

This paper presents an alternative statistical signal analysis method to characterise and determine Youngs modulus property of metallic materials. For this characterisation purpose, we propose an alternative method called Integrated Kurtosis-based Algorithm for Z-notch filter (I-kazTM) and Mesokurtosis Zonal Nonparametric (M-Z-N). Impulsive excitation test has been performed according to ASTM E1876 on three metallic materials of medium carbon steel S50C, stainless steel AISI 304 and brass to measure the piezoelectric and acoustic signals. The transient acoustic signal has been analysed using M-Z-N analysis while I-kazTM has been used to analyse the impulsive piezoelectric signal. Correlation expression between Youngs modulus property and the calculated statistical parameters has been discussed and the accuracy of these two methods has been identified using cast iron FCD 500 specimen.

APA, Harvard, Vancouver, ISO, and other styles

25

Li, Sen, Xiaojing Chen, and Rongxi He. "Robust Cyclic MUSIC Algorithm for Finding Directions in Impulsive Noise Environment." International Journal of Antennas and Propagation 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/9038341.

Full text

Abstract:

This paper addresses the issue of direction finding of a cyclostationary signal under impulsive noise environments modeled byα-stable distribution. Sinceα-stable distribution does not have finite second-order statistics, the conventional cyclic correlation-based signal-selective direction finding algorithms do not work effectively. To resolve this problem, we define two robust cyclic correlation functions which are derived from robust statistics property of the correntropy and the nonlinear transformation, respectively. The MUSIC algorithm with the robust cyclic correlation matrix of the received signals of arrays is then used to estimate the direction of cyclostationary signal in the presence of impulsive noise. The computer simulation results demonstrate that the two proposed robust cyclic correlation-based algorithms outperform the conventional cyclic correlation and the fractional lower order cyclic correlation based methods.

APA, Harvard, Vancouver, ISO, and other styles

26

Rao*, G. Manmadha, Raidu Babu D.N, Krishna Kanth P.S.L, Vinay B., and Nikhil V. "Reduction of Impulsive Noise from Speech and Audio Signals by using Sd-Rom Algorithm." International Journal of Recent Technology and Engineering 10, no. 1 (May 30, 2021): 265–68. http://dx.doi.org/10.35940/ijrte.a5943.0510121.

Full text

Abstract:

Removal of noise is the heart for speech and audio signal processing. Impulse noise is one of the most important noise which corrupts different parts in speech and audio signals. To remove this type of noise from speech and audio signals the technique proposed in this work is signal dependent rank order mean (SD-ROM) method in recursive version. This technique is used to replace the impulse noise samples based on the neighbouring samples. It detects the impulse noise samples based on the rank ordered differences with threshold values. This technique doesn’t change the features and tonal quality of signal. Rank ordered differences is used for detecting the impulse noise samples in speech and audio signals. Once the sample is detected as corrupted sample, that sample is replaced with rank ordered mean value and this rank ordered mean value depends on the sliding window size and neighbouring samples. This technique shows good results in terms of signal to noise ratio (SNR) and peak signal to noise ratio (PSNR) when compared with other techniques. It mainly used for removal of impulse noises from speech and audio signals.

APA, Harvard, Vancouver, ISO, and other styles

27

Huang, Shiguo, Yujun Niu, and Yajing Xu. "Exponential Stability of Impulsive Stochastic Delay System Based on Razumikhin Method and Its Application to Chaos Control." Mathematical Problems in Engineering 2021 (August 23, 2021): 1–6. http://dx.doi.org/10.1155/2021/2220301.

Full text

Abstract:

In this paper, the exponential stability of a stochastic delay system with impulsive signal is considered, and stability theorem of this system is proposed based on the Lyapunov–Razumikhin method; the convergence rate is also given, which gives theoretical foundation to chaos control and synchronization using the impulsive method. Finally, the classic delay chaos system with white noise and impulsive signal is employed to verify the feasibility and effectiveness of our theorem.

APA, Harvard, Vancouver, ISO, and other styles

28

Shi, Yawei, Hongjuan Wu, and Chuandong Li. "Constrained hybrid control for parametric uncertainty systems via step-function method." Mathematical Biosciences and Engineering 19, no. 11 (2022): 10741–61. http://dx.doi.org/10.3934/mbe.2022503.

Full text

Abstract:

<abstract><p>In this paper, considering that sometimes signal transmission may be interrupted, or signal input errors may occur, we establish a novel class of parametric uncertainty hybrid control system models including the impulsive control signals under saturated inputs, which can reflect the signal transmission process more realistically. Based on the step-function method, improved polytopic representation approach and Schur complement, we find the stability conditions, which are less conservative than those with the traditional Lyapunov method, of the considered control system. In addition, we investigate the design of the control gains and the auxiliary control gains for easily finding the suitable control signals, the auxiliary signals and the estimation of the attraction domain. Moreover, our proposed methods are applied to the fixed time impulse problems of uncertain systems with or without Zeno behavior. Simulation results for the uncertain neural network systems are presented to show the feasibility and effectiveness of our stabilization methods using the step-function.</p></abstract>

APA, Harvard, Vancouver, ISO, and other styles

29

Hilal, H. Abu. "Spectral Efficiency Performance of Multi Cell MIMO Systems in Impulsive Noise Channels." International Journal of Circuits, Systems and Signal Processing 17 (March 6, 2023): 92–99. http://dx.doi.org/10.46300/9106.2023.17.11.

Full text

Abstract:

This research report details how impulsive noise affects communication systems. This research evaluates the differences and similarities among impulse models in communication systems. After comparing and contrasting the impulse noise models' similarities and differences, the models' service execution will be compared. Spectral efficiency is the fundamental criterion for comparing models' service execution. Comparing models under different impulse noise levels and inter- cell and intra-cell intercession will also be done. The 5G mm Wave multiple input/output system's service execution will be researched. The study will use IN. First, the Gaussian noise scenario will be deduced for the stated device's performance, followed by the non- Gaussian noise scenario derivation. The latter deriva- tion also involves averaging Gaussian noise in terms of impulsive noise's spread. Monte Carlo simulations are used to show and support derivations.

APA, Harvard, Vancouver, ISO, and other styles

30

Lee, Dong-Hyeon, Chinsuk Hong, Weui-Bong Jeong, and Sejin Ahn. "Time–Frequency Envelope Analysis for Fault Detection of Rotating Machinery Signals with Impulsive Noise." Applied Sciences 11, no. 12 (June 9, 2021): 5373. http://dx.doi.org/10.3390/app11125373.

Full text

Abstract:

Envelope analysis is a widely used tool for fault detection in rotating machines. In envelope analysis, impulsive noise contaminates the measured signal, making it difficult to extract the features of defects. This paper proposes a time–frequency envelope analysis that overcomes the effects of impulsive noises. Envelope analysis is performed by dividing the signal into several sections through a time window. The effect of impulsive noises is eliminated by using the frequency characteristics of the short time rectangular wave. The proposed method was verified through simulation and experimental data. The simulation was conducted by mathematically modeling a cyclo-stationary process that characterizes rotating machinery signals. In addition, the effectiveness of the method was verified by the measured data of normal and defective air-conditioners produced on the actual assembly line. This simple proposed method is effective enough to detect the faults. In the future, the approaches of big data and deep learning will be required for the development of the prognostic health-management framework.

APA, Harvard, Vancouver, ISO, and other styles

31

Schmidt, Stephan, Radoslaw Zimroz, Fakher Chaari, P. Stephan Heyns, and Mohamed Haddar. "A Simple Condition Monitoring Method for Gearboxes Operating in Impulsive Environments." Sensors 20, no. 7 (April 9, 2020): 2115. http://dx.doi.org/10.3390/s20072115.

Full text

Abstract:

Reliable condition indicators are necessary to perform effective diagnosis and prognosis. However, the vibration signals are often corrupted with non-Gaussian noise and rotating machines may operate under time-varying operating conditions. This impedes the application of conventional condition indicators. The synchronous average of the squared envelope is a relatively simple yet effective method to perform fault detection, fault identification and fault trending under constant and time-varying operating conditions. However, its performance is impeded by the presence of impulsive signal components attributed to impulsive noise or the presence of other damage modes in the machine. In this work, it is proposed that the synchronous median of the squared envelope should be used instead of the synchronous average of the squared envelope for gearbox fault diagnosis. It is shown on numerical and experimental datasets that the synchronous median is more robust to the presence of impulsive signal components and is therefore more reliable for estimating the condition of specific machine components.

APA, Harvard, Vancouver, ISO, and other styles

32

Żak, Grzegorz, Marek Teuerle, Agnieszka Wyłomańska, and Radosław Zimroz. "Measures of Dependence for α-Stable Distributed Processes and Its Application to Diagnostics of Local Damage in Presence of Impulsive Noise." Shock and Vibration 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/1963769.

Full text

Abstract:

Local damage detection in rotating machinery is simply searching for cyclic impulsive signal in noisy observation. Such raw signal is mixture of various components with specific properties (deterministic, random, cyclic, impulsive, etc.). The problem appears when the investigated process is based on one of the heavy-tailed distributions. In this case the classical measure can not be considered. Therefore, alternative measures of dependence adequate for such processes should be considered. In this paper we examine the structure of dependence of alpha-stable based systems expressed by means of two measures, namely, codifference and covariation. The reason for using alpha-stable distribution is simple and intuitive: signal of interest is impulsive so its distribution is heavy-tailed. The main goal is to introduce a new technique for estimation of covariation. Due to the complex nature of such vibration signals applying novel methods instead of classical ones is recommended. Classical algorithms usually are based on the assumption that theoretical second moment is finite, which is not true in case of the data acquired on the faulty components. Main advantage of our proposed algorithm is independence from second moment assumption.

APA, Harvard, Vancouver, ISO, and other styles

33

Dou, Yuzi, and Sen Li. "Kernel Function-Based Ambiguity Function and Its Application on DOA Estimation in Impulsive Noise." Sensors 22, no. 18 (September 15, 2022): 6996. http://dx.doi.org/10.3390/s22186996.

Full text

Abstract:

To solve the problem that the traditional ambiguity function cannot well reflect the time-frequency distribution characteristics of linear frequency modulated (LFM) signals due to the presence of impulsive noise, two robust ambiguity functions: correntropy-based ambiguity function (CRAF) and fractional lower order correntropy-based ambiguity function (FLOCRAF) are defined based on the feature that correntropy kernel function can effectively suppress impulsive noise. Then these two robust ambiguity functions are used to estimate the direction of arrival (DOA) of narrowband LFM signal under an impulsive noise environment. Instead of the covariance matrix used in the ESPRIT algorithm by the spatial CRAF matrix and FLOCRAF matrix, the CRAF-ESPRIT and FLOCRAF-ESPRIT algorithms are proposed. Computer simulation results show that compared with the algorithms only using ambiguity function and the algorithms only using the correntropy kernel function-based correlation, the proposed algorithms using ambiguity function based on correntropy kernel function have good performance in terms of probability of resolution and estimation accuracy under various circumstances. Especially, the performance of the FLOCRAF-ESPRIT algorithm is better than the CRAF-ESPRIT algorithm in the environment of low generalized signal-to-noise ratio and strong impulsive noise.

APA, Harvard, Vancouver, ISO, and other styles

34

Randall, R. B. "Applications of Spectral Kurtosis in Machine Diagnostics and Prognostics." Key Engineering Materials 293-294 (September 2005): 21–32. http://dx.doi.org/10.4028/www.scientific.net/kem.293-294.21.

Full text

Abstract:

Many machine faults, such as local defects in bearings and gears, manifest themselves in vibration signals as a series of impulsive events. Kurtosis is a measure of the impulsiveness of a signal, and spectral kurtosis (SK) gives an indication of how the kurtosis (of a bandpass filtered signal) varies with frequency. This not only gives an indication of the frequency bands to be processed, but can also be used to generate a filter to extract the most impulsive part of a signal. The first step in calculating SK is to perform a time/frequency decomposition of the signal, and then calculate the kurtosis for each frequency line. The paper compares the original STFT (short time Fourier transform) with wavelet analysis for the time/frequency decomposition, and for determining the optimum combination of centre frequency and bandwidth for maximizing the SK. The paper also describes how the SK can be enhanced by “prewhitening” the signal using an autoregressive (AR) model, this sometimes revealing an incipient fault at a much earlier stage.

APA, Harvard, Vancouver, ISO, and other styles

35

BROTZ, R., R. MARSCHALL, and M. KNECHT. "SIGNAL ADJUSTMENT OF VIBROSEIS AND IMPULSIVE SOURCE DATA*." Geophysical Prospecting 35, no. 7 (September 1987): 739–66. http://dx.doi.org/10.1111/j.1365-2478.1987.tb02256.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Gao, T., C. Du, Z. Ye, L. Xie, J. Zhang, and Y. Wang. "Smoothing Position Error Signal Corrupted by Impulsive Disturbances." IEEE Transactions on Magnetics 45, no. 11 (November 2009): 5082–87. http://dx.doi.org/10.1109/tmag.2009.2029619.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Wang, Hongchao, and Wenliao Du. "Fast Spectral Correlation Based on Sparse Representation Self-Learning Dictionary and Its Application in Fault Diagnosis of Rotating Machinery." Complexity 2020 (August 18, 2020): 1–14. http://dx.doi.org/10.1155/2020/9857839.

Full text

Abstract:

Rolling element bearing and gear are the typical supporting or rotating parts in mechanical equipment, and it has important economy and security to realize their quick and accurate fault detection. As one kind of powerful cyclostationarity signal analyzing method, spectral correlation (SC) could identify the impulsive characteristic component buried in the vibration signals of rotating machinery effectively. However, the fault feature such as impulsive characteristic component is often interfered by other background noise, and the situation is serious especially in early weak fault stage. Besides, the traditional SC method has a drawback of low computation efficiency which hinders its wide application to some extent. To address the above problems, an impulsive feature-enhanced method which combines fast spectral correlation (FSC) with sparse representation self-learning dictionary is proposed in the paper. Firstly, the sparse representation self-learning dictionary method-K-means singular value decomposition (KSVD) is improved and the improved KSVD (IKSVD) method is used to denoise the original signal, and the periodic impulses are highlighted. Then, the FSC algorithm is applied on the denoised signal and spectral correlation image could be obtained. Finally, the calculated enhanced envelope spectrum (EES) of the denoised signal is obtained by using the spectral correlation image to identify the accurate fault position. The feasibility and superiority of the proposed method is verified through simulation, experiment, and engineering application.

APA, Harvard, Vancouver, ISO, and other styles

38

Lee, Sang Kwon, Jang Sun Shim, and Byung-Og Cho. "Damage Detection of a Gear with Initial Pitting Using the Zoomed Phase Map of Continuous Wavelet Transform." Key Engineering Materials 306-308 (March 2006): 223–28. http://dx.doi.org/10.4028/www.scientific.net/kem.306-308.223.

Full text

Abstract:

Impulsive vibration generated by localized gear damage can be used as an indicator for damage detection. Local damage induces an abrupt increase of the amplitude and phase lag of the impulsive vibration signal measured on the gearbox. Relatively large damage like “tip breakage” can be easily detected by the amplitude map of CWT (continuous wavelet transform) for the impulsive vibration signal measured on the gearbox. However, minor damage like “initial pitting” cannot be detected with the amplitude map. To overcome this problem, in this paper we take into account the phase map for a damage signal. The zoomed phase map of CWT is successfully applied to the detection of minor gearbox damage.

APA, Harvard, Vancouver, ISO, and other styles

39

Zhou, Qing, Xia Yang, Yong Jian Mao, and Hong Jian Deng. "Wavelet Analysis of Transient Signals of Structural Responses to Impulsive Loads." Advanced Materials Research 452-453 (January 2012): 1522–26. http://dx.doi.org/10.4028/www.scientific.net/amr.452-453.1522.

Full text

Abstract:

Based on a brief introduction to elementary theory of wavelet analysis, the disadvantages of wavelet method and wavelet packet method are given. A new wavelet analysis procedure is proposed for decomposition and reconstruction of measured transient signals. This method can search by specific frequency paths, then overcomes the shortcomings of uniform frequency intervals in pure wavelet analyses and of large computational costs in common wavelet packet analyses. As examples, a signal-noise separation and a weak signal extraction are given to show the effectiveness of the new procedure.

APA, Harvard, Vancouver, ISO, and other styles

40

SHAGHAGHI, M., M. H. KAHAEI, and J. POSHTAN. "RESONANCE-BASED VIBRATION SIGNAL DENOISING USING WAVELET PACKET DECOMPOSITION." Fluctuation and Noise Letters 07, no. 03 (September 2007): L257—L262. http://dx.doi.org/10.1142/s021947750700391x.

Full text

Abstract:

This paper presents a new on-line technique for denoising impulsive vibration signals in noisy environments using Wavelet Packets. The proposed algorithm is based on localizing the frequency subbands of the resonances embedded in impulsive vibration signals. The performance of the algorithm is evaluated in denoising real vibration signals measured from faulty bearings. The results compared to the theoretical values and those obtained by the HFD algorithm show the effectiveness of the proposed algorithm while the computational cost reduces to half.

APA, Harvard, Vancouver, ISO, and other styles

41

BARRABÈS, C., and P. A. HOGAN. "DETECTION OF IMPULSIVE LIGHT-LIKE SIGNALS IN GENERAL RELATIVITY." International Journal of Modern Physics D 10, no. 05 (October 2001): 711–21. http://dx.doi.org/10.1142/s0218271801001098.

Full text

Abstract:

The principal purpose of this paper is to study the effect of an impulsive light-like signal on neighbouring test particles. Such a signal can in general be unambiguously decomposed into a light-like shell of null matter and an impulsive gravitational wave. Our results are: (a) If there is anisotropic stress in the light-like shell then test particles initially moving in the signal front are displaced out of this 2-surface after encountering the signal; (b) For a light-like shell with no anisotropic stress accompanying a gravitational wave the effect of the signal on test particles moving in the signal front is to displace them relative to each other with the usual distortion due to the gravitational wave diminished by the presence of the light-like shell. An explicit example for a plane-fronted signal is worked out.

APA, Harvard, Vancouver, ISO, and other styles

42

ITOH, MAKOTO, TAO YANG, and LEON O. CHUA. "CONDITIONS FOR IMPULSIVE SYNCHRONIZATION OF CHAOTIC AND HYPERCHAOTIC SYSTEMS." International Journal of Bifurcation and Chaos 11, no. 02 (February 2001): 551–60. http://dx.doi.org/10.1142/s0218127401002262.

Full text

Abstract:

Experimental results show that chaotic and hyperchaotic systems can be synchronized by impulses sampled from one or two state variables. In this paper, we study the conditions under which chaotic and hyperchaotic systems can be synchronized by impulses sampled from a part of their state variables. By calculating the Lyapunov exponents of variational synchronization error systems, we show that this kind of impulsive synchronization can be applied to almost all hyperchaotic systems. We also study the selective synchronization of chaotic systems. In a selective synchronization scheme, the synchronizing signal is chosen in the time periods when the Lyapunov exponents of variational synchronization error systems are negative. Since only driving signals during the time periods when synchronization error can be reduced are applied to reduce the synchronization error, and no signal is applied during the time periods when synchronization error can be increased, selective synchronization scheme can be used to achieve synchronization even in the case when continuous synchronization schemes fail to work.

APA, Harvard, Vancouver, ISO, and other styles

43

WANG, XING-YUAN, and MING-JUN WANG. "IMPULSIVE SYNCHRONIZATION OF HYPERCHAOTIC LÜ SYSTEM." International Journal of Modern Physics B 25, no. 27 (October 30, 2011): 3671–78. http://dx.doi.org/10.1142/s0217979211100862.

Full text

Abstract:

In this paper, the impulsive synchronization of hyperchaotic Lü systems is discussed. The sufficient conditions on feedback strength and impulsive interval are established to guarantee the synchronization. The method is proved true by Lyapunov stability theory. In addition, a scheme of impulsive synchronization via transmitting single signal is presented. Numerical simulations show the effectiveness of the methods.

APA, Harvard, Vancouver, ISO, and other styles

44

Zimroz, Radoslaw, and Walter Bartelmus. "Application of Adaptive Filtering for Weak Impulsive Signal Recovery for Bearings Local Damage Detection in Complex Mining Mechanical Systems Working under Condition of Varying Load." Solid State Phenomena 180 (November 2011): 250–57. http://dx.doi.org/10.4028/www.scientific.net/ssp.180.250.

Full text

Abstract:

The paper shows application of an adaptive filter as a pre-processor for impulsive cyclic weak signal recovery from raw vibration signals captured from complex mechanical systems used in the industry (namely bearings used in pulleys – parts of driving units for belt conveyors). Periodic/cyclic impulses are related to local faults which cause impulse/concentric forces/stresses in kinematic pairs. Typical examples of such local faults which cause mechanical system condition change are spall/pitting on bearings elements: outer/inner races and/or rolling elements. For analyzed objects, impulses associated with local faults are masked by other signal sources. In the first part of the paper are presented objects for the better understanding of mechanical phenomena that exist in the system, then preliminary signal analysis will be performed (in time, frequency and time-frequency domain) for the identification of signal nature. Next the idea of an adaptive system and the brief description of Normalized Least Mean Square (NLMS) algorithm will be presented. Application of NLMS is better than classical LMS due to stability of the adaptation. In the last section the results of adaptive filtering for signals from bearings is discussed. Authors show application of NLMS (for the first time in literature) for the case when signals are received from machines working in industrial condition. There were made only trails when the machines were investigated in laboratory conditions.

APA, Harvard, Vancouver, ISO, and other styles

45

Gao, Lijun. "p-Moment Stability of Stochastic Differential Delay Systems with Impulsive Jump and Markovian Switching." Mathematical Problems in Engineering 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/401538.

Full text

Abstract:

This paper investigatesp-moment stability of the stochastic differential delay systems with impulsive jump and Markovian switching. Some stability criteria are obtained based on Lyapunov functional method and stochastic theory. It is shown that, even if all the subsystems governing the continuous dynamics without impulse are not stable, as impulsive and switching signal satisfies a dwell-time upper bound condition, impulses can stabilize the systems in thep-moment stability sense. The opposite situation is also developed for which all the subsystems governing the continuous dynamics arep-moment stable. The results can be easily applied to stochastic systems with arbitrarily large delays. The efficiency of the proposed results is illustrated by two numerical examples.

APA, Harvard, Vancouver, ISO, and other styles

46

An, Chunlian, Guyue Yang, Liangliang Tian, Jing Song, and Yi Wang. "DOA Estimation for Noncircular Signals under Strong Impulsive Noise." Mathematical Problems in Engineering 2022 (August 8, 2022): 1–9. http://dx.doi.org/10.1155/2022/6909666.

Full text

Abstract:

Direction of arrival (DOA) estimation under impulsive noise has been an important research area. Most present methods are based on the fractional lower order statistics, while the computation load is heavy, and the estimation property degrades when the noise impact is strong. To get around this conundrum, a novel solution is presented, where the noncircular signals are introduced for modelling, a filtering preprocessing method is introduced to eliminate the impulsive noise, and a matrix reconstruction method is presented to smooth the residual noise. Firstly, the filtering preprocessing method is implemented to cut out the impulsive noise. Secondly, the characteristic of the noncircular signal is utilized to extend the array aperture. Thirdly, a new matrix reconstruction method is proposed to smooth the residual noise. Finally, the classical ESPRIT algorithm is adopted to estimate the DOAs. Simulations under different comparison of dimensions are conducted, and the mainstream methods are selected as comparison. The simulation results illustrate the outstanding performance of the proposed method in a strong impulsive noise environment.

APA, Harvard, Vancouver, ISO, and other styles

47

Shafieipour, Mohammad, Heng-Siong Lim, and Teong-Chee Chuah. "Decoding of Turbo Codes in Symmetric Alpha-Stable Noise." ISRN Signal Processing 2011 (March 29, 2011): 1–7. http://dx.doi.org/10.5402/2011/683972.

Full text

Abstract:

This paper investigates the decoding of turbo codes in impulsive symmetric α-stable (SαS) noise. Due to the nonexistence of a closed-form expression for the probability density function (pdf) of α-stable processes, numerical-based SαS pdf is used to derive branch transition probability (btp) for the maximum a posteriori turbo decoder. Results show that in Gaussian noise, the turbo decoder achieves similar performance using both the conventional and the proposed btps, but in impulsive channels, the turbo decoder with the proposed btp substantially outperforms the turbo decoder utilizing the conventional btp. Results also confirm that the turbo decoder incorporating the proposed btp outperforms the existing Cauchy-based turbo decoder in non-Cauchy impulsive noise, while the two decoders accomplish similar performance in Cauchy noise.

APA, Harvard, Vancouver, ISO, and other styles

48

S.Hallikar, Rohini, M. Uttarakumari, Padmaraju K, and Yashas D. "Modified Turbo and SDROM Method for Speech Processing for Cochlear Implants." International Journal of Engineering & Technology 7, no. 4.5 (September 22, 2018): 179. http://dx.doi.org/10.14419/ijet.v7i4.5.20040.

Full text

Abstract:

A performance comparison of Signal Dependent Rank Order Mean (SDROM) method of speech signal enhancement with a speech enhancement method which makes use of a Turbo combination and SDROM filter referred to as modified Turbo and SDROM technique is made in this paper. Normally, speech signals are used as inputs to a cochlear implant signal processing unit.Sounds are corrupted by different noises such as AWGN, Impulsive noise and babble. The results are evaluated in terms of enhancements evaluations done by basically three parameters namely correlation coefficient, log spectral distortion (LSD) and segmental signal to noise ratio(SSNR). These parameters are calculated between the processed and the clean signals.. Results prove the superior performance of the new method especially for AWGN corrupted speech.

APA, Harvard, Vancouver, ISO, and other styles

49

Brown, C. L., and A. M. Zoubir. "A nonparametric approach to signal detection in impulsive interference." IEEE Transactions on Signal Processing 48, no. 9 (2000): 2665–69. http://dx.doi.org/10.1109/78.863074.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Maras, A., H. Davidson, and A. Holt. "Weak-Signal DPSK Detection in Narrow-Band Impulsive Noise." IEEE Transactions on Communications 33, no. 9 (1985): 1008–11. http://dx.doi.org/10.1109/tcom.1985.1096416.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Impulsive signal'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles