scholarly journals Gradient Based Adaptive Algorithm for Echo Cancellation from Recorded Echo Corrupted Speech

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Upal Mahbub ◽  
Shaikh Anowarul Fattah
Keyword(s):  
Speech Signal ◽  
Single Channel ◽  
Reference Signal ◽  
Real Life ◽  
Echo Cancellation ◽  
Lms Algorithm ◽  
Gradient Based ◽  
Continuous Feedback ◽  
Original Speech

An offline single channel acoustic echo cancellation (AEC) scheme is proposed based on gradient based adaptive least mean squares (LMS) algorithm considering a major practical application of echo cancellation system for enhancing recorded echo corrupted speech data. The unavailability of a reference signal makes the problem of single channel adaptive echo cancellation to be extremely difficult to handle. Moreover, continuous feedback of the echo corrupted signal to the input microphone can significantly degrade the quality of the original speech signal and may even result in howling. In order to overcome these problems, in the proposed scheme, the delayed version of the echo corrupted speech signal is considered as a reference. An objective function is thus formulated and thereby a modified LMS update equation is derived, which is shown to converge to the optimum Wiener-Hopf solution. The performance of the proposed method is evaluated in terms of both subjective and objective measures via extensive experimentation on several real-life echo corrupted signals and very satisfactory performance is obtained.

scholarly journals Speech Scrambling Based on Chaotic Mapping and Random Permutation for Modern Mobile Communication Systems

2017 ◽  
Vol 2 (1) ◽  
pp. 20-25
Author(s):  
Dhanya G ◽  
J Jayakumari
Keyword(s):  
Speech Signal ◽  
Communication Systems ◽  
Random Permutation ◽  
Test Results ◽  
Chaotic Mapping ◽  
Intelligible Speech ◽  
Network Communications ◽  
Encryption Algorithms ◽  
Original Speech

The expanding significance of securing data over the network has promoted growth of strong encryption algorithms. To enhance the information protection in network communications, this paper presents a Random permutation, chaotic mapping and pseudo random binary scrambling. It involves transforming the intelligible speech signal into an unintelligible form to protect it from interrupters. In this report, suggest a simple and secure procedure to secure the speech signal. The speech scrambling process makes use of two Permutations. In the first step, Random permutation algorithm is used to swap the rows of the original speech followed by swapping of rows using chaotic Bernoulli mapping. This produces an intermediary scrambled speech. In the second measure, pseudo random binary generator is used to make the final scrambled signal. Various analysis tests are then executed to determine the quality of the encrypted image. The test results determine the efficiency of the proposed speech scrambling process.

Qualitative assessment of equipment failure cause finding and removal

2018 ◽  
pp. 116-126
Author(s):  
E. A. Vakulin ◽  
A. I. Zayats ◽  
V. A. Beklemeshev ◽  
V. A. Ivashkevich ◽  
V. A. Khazhiev ◽  
...  
Keyword(s):  
Production Condition ◽  
Real Life ◽  
Open Pit Mine ◽  
Qualitative Assessment ◽  
Open Pit ◽  
Quality Level ◽  
Equipment Failure ◽  
Operation Conditions ◽  
Failure Investigation

Investigation of failures is one of the critical activities of mining and haulage equipment operability assurance in mining. Maintaining failure investigation at the required quality level, it is possible to identify provisions, rules and procedures that should be revised or changed, operation conditions that should be improved, additional personnel training, if required, etc. Investigation of failures in mines is under responsibility of machine men and electricians of maintenance and operation services. In reality, factory management and setup for production condition weak concernment of these workers in quality investigation aimed at finding of sources of equipment failures. This article describes real-life results achieved in development and use of maintenance service operation, technology and management monitoring. The requirements are substantiated for quality improvement in failure cause finding and removal in mining and haulage equipment at Chernogorsky open pit mine, SUEK-Khakassia. Causes of the present quality of failure investigation by machine men of Chernogorsky Repair and Engineering Works and Chernogorsky open pit mine are revealed. The proposed recommended practices will improve quality of mining and haulage equipment failure investigation.

The Relationship between the Development of Human Capital and the Agricultural Economy in Rural Areas

2020 ◽  
pp. 61-65
Author(s):  
B.A. Voronin ◽  
◽  
I.P. Chupina ◽  
Ya.V. Voronina ◽  
◽  
...  
Keyword(s):  
Human Capital ◽  
Rural Areas ◽  
Agricultural Production ◽  
Agricultural Sector ◽  
Real Life ◽  
Standard View ◽  
Household Factors ◽  
Economic Transformations ◽  
The Relationship

The article discusses a non-standard view of the formation of human capital for work in organizations of the agricultural sector of the economy, in the context of modern socio-economic transformations. In the classical sense, human capital for agriculture should be formed and developed in rural areas. But in real life, this is not always the case, because there are many factors that prevent the classical solution of this problem. First, the demographic factor affects, second, social and household factors, and third, in many rural areas there are no working agricultural organizations where qualified agricultural specialists can work. All these and other circumstances actualize the problem of the quality of human capital in rural areas in relation to the development of agricultural production.

Implementation of a single-channel active noise control system with multiple reference sensors

2020 ◽  
Vol 68 (5) ◽  
pp. 358-366
Author(s):  
H.E. Oh ◽  
W.B. Jeong ◽  
C. Hong
Keyword(s):  
Single Channel ◽  
Control Method ◽  
Reference Signal ◽  
Active Noise Control ◽  
Multiple Source ◽  
Weighted Sum ◽  
Reference Signals ◽  
Feedforward Controller ◽  
Channel Control ◽  
Source Signals

When multiple sources contribute competitively to the noise level, multi-channel control architecture is needed, leading to more cost and time for control computation. We, hence, are concerned with a single-channel control method with a single-reference signal obtained from a linear combination of the multiple source signals. First, we selected 3 source signal sensors for the reference signals and the error sensor, selected a proper actuator and designed the controllers: 3 cases of single-channel feedforward controllers with a single-reference signal respectively from the source signals, a multi-channel feedforward controller with the reference signals from the source signals, and the proposed controller with the reference signal from weighted sum of the source signals. The weighting factors and the filter coefficients of the controller were determined by the FxLMS algorithm. An experiment was then performed to confirm the effectiveness of the proposed method comparing the control performance with other methods for a tower air conditioner. The overall sound pressure level (SPL) detected by the error sensor is compared to evaluate their performance. The reduction in the overall SPL was obtained by 4.74 dB, 1.96 dB and 6.62 dB, respectively, when using each of the 3 reference signals. Also, the overall SPL was reduced by 7.12 dB when using the multi-reference controller and by 7.66 dB when using the proposed controller. Conclusively, under the multiple source contribution, a single-channel feed forward controller with the reference signal from a weighted sum of the source signals works well with lower cost than multi-channel feedforward controller.

Singular Values Decomposition and Lifting Wavelet Transform for Speech Signal Embedding into Digital Image

2019 ◽  
Vol 12 (2) ◽  
pp. 138-151
Author(s):  
Mourad Talbi ◽  
Med Salim Bouhlel
Keyword(s):  
Wavelet Transform ◽  
Speech Signal ◽  
Signal To Noise Ratio ◽  
Perceptual Quality ◽  
Lifting Wavelet Transform ◽  
Signal To Noise ◽  
Perceptual Evaluation ◽  
Lifting Wavelet ◽  
Noise Ratio

Background: In this paper, we propose a secure image watermarking technique which is applied to grayscale and color images. It consists in applying the SVD (Singular Value Decomposition) in the Lifting Wavelet Transform domain for embedding a speech image (the watermark) into the host image. Methods: It also uses signature in the embedding and extraction steps. Its performance is justified by the computation of PSNR (Pick Signal to Noise Ratio), SSIM (Structural Similarity), SNR (Signal to Noise Ratio), SegSNR (Segmental SNR) and PESQ (Perceptual Evaluation Speech Quality). Results: The PSNR and SSIM are used for evaluating the perceptual quality of the watermarked image compared to the original image. The SNR, SegSNR and PESQ are used for evaluating the perceptual quality of the reconstructed or extracted speech signal compared to the original speech signal. Conclusion: The Results obtained from computation of PSNR, SSIM, SNR, SegSNR and PESQ show the performance of the proposed technique.

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