Search results for "impulse noise"
showing 10 items of 10 documents
Cardiovascular effects of impulse noise, road traffic noise, and intermittent pink noise at LAeq = 75 dB, as a function of sex, age, and level of anx…
1992
In a previous paper, in which the experimental conditions of the present research are fully described (Parrot et al., this issue), heart rate (HR) was studied in 60 male and in 60 female subjects in response to a pile-driver noise (P), a gunfire noise (G), a road traffic noise (T), and an intermittent pink noise (R), all noises being emitted at the same LAeq = 75 dB for 15 min. Digital pulse level (PL) responses were concomitantly surveyed by the use of pulse oximetry, allowing continuous arterial oxygen saturation (SaO2) readings. An index of pulse reactivity (PRI) could be calculated. Arterial blood pressure was measured 7 times from the beginning to the end of each trial. At rest, within…
Impulse noise removal on an embedded, low memory SIMD processor
2003
Vector median filters efficiently reduce noise while preserving image details. However, their high computational complexity for color images makes them impractical for real-time systems. We propose new computationally efficient filtering algorithms, called index mapping filters (IMF). These filtering algorithms are accelerated by implementing them on a massively data parallel processor array. In addition to greater computational efficiency, these algorithms result in robust noise reduction of corrupted color images. Analyses of mean square error, signal-to-noise-ratio, and visual comparison metrics indicate that IMF are competitive with the vector median filter (VMF) in their ability to cor…
Steady-state and tracking analysis of a robust adaptive filter with low computational cost
2007
This paper analyses a new adaptive algorithm that is robust to impulse noise and has a low computational load [E. Soria, J.D. Martin, A.J. Serrano, J. Calpe, and J. Chambers, A new robust adaptive algorithm with low computacional cost, Electron. Lett. 42 (1) (2006) 60-62]. The algorithm is based on two premises: the use of the cost function often used in independent component analysis and a fuzzy modelling of the hyperbolic tangent function. The steady-state error and tracking capability of the algorithm are analysed using conservation methods [A. Sayed, Fundamentals of Adaptive Filtering, Wiley, New York, 2003], thus verifying the correspondence between theory and experimental results.
Lärm als Umweltproblem
1976
Noise as an Environmental Problem. Anatomical structure and physiological function of the human ear are described. It is shown that constant noise stress leads to damage of certain parts of the inner ear. These damages proceed characteristically and may be diagnosed relatively early by means of audiometric tests. VDI-instructions 2058 (sheet 2) prescribes screening-tests for an earliest possible detection of incipient noise damage. In addition to ear-damaging effects of noise there have also been recorded physiological reactions under noise influence. Such disturbances, however, cannot as yet be described as an “Extraaural disease”. On the other hand, the fact that high sound intensities of…
Noise estimation from digital step-model signal
2013
International audience; This paper addresses the noise estimation in the digital domain and proposes a noise estimator based on the step signal model. It is efficient for any distribution of noise because it does not rely only on the smallest amplitudes in the signal or image. The proposed approach uses polarized/directional derivatives and a nonlinear combination of these derivatives to estimate the noise distribution (e.g., Gaussian, Poisson, speckle, etc.). The moments of this measured distribution can be computed and are also calculated theoretically on the basis of noise distribution models. The 1D performances are detailed, and as our work is mostly dedicated to image processing, a 2D…
Patch-Based Image Denoising Model for Mixed Gaussian Impulse Noise Using L1 Norm
2017
Image denoising is the classes of technique used to free the image form the noise. The noise in the image may be added during the observation process due to the improper setting of the camera lance, low-resolution camera, cheap, and low-quality sensors, etc. Noise in the image may also be added during the image restoration, image transmission through the transmission media. To obtain required information from image, image must be noise free, i.e., high-frequency details must be present in the image. There are number of applications where image denoising is needed such as remote location detection, computer vision, computer graphics, video surveillance, etc. In last two decades, numbers of m…
Cardiovascular effects of impulse noise, road traffic noise, and intermittent pink noise at LAeq = 75 dB, as a function of sex, age, and level of anx…
1992
This study aimed at comparing for their cardiovascular effects: a pile-driver noise (P), a gunfire noise (G), a road traffic noise (T), an intermittent pink noise (R). All noises were presented at the same LAeq = 75 dB for 15 min each. Some 120 subjects were divided into 8 subgroups of 15 subjects each: OM (men between 40 and 50 years of age), OF (women, same age range), YM (men, between 15 and 20 years of age), YF (women, same age range), AM (typically anxious men, 20–25 years of age), AF (typically anxious women, same age range), NM (typicall anxiety-free men, same age range), and NF (typically anxiety-free women, same age range). Heart rate (HR), digital pulse level, and arterial blood p…
FPGA Implementation of an Adaptive Filter Robust to Impulsive Noise: Two Approaches
2011
Adaptive filters are used in a wide range of applications such as echo cancellation, noise cancellation, system identification, and prediction. Its hardware implementation becomes essential in many cases where real-time execution is needed. However, impulsive noise affects the proper operation of the filter and the adaptation process. This noise is one of the most damaging types of signal distortion, not always considered when implementing algorithms, particularly in specific hardware platforms. Field-programmable gate arrays (FPGAs) are used widely for real-time applications where timing requirements are strict. Nowadays, two main design processes can be followed for embedded system design…
Implementation of a new adaptive algorithm using fuzzy cost function and robust to impulsive noise
2012
Adaptive filters are used in a wide range of applications such as noise cancellation, system identification, and prediction. One of the main problems for theses filters is the impulsive noise as it generates algorithm unstability. This work shows the development, simulation and hardware implementation of a new algorithm robust to impulsive noise. Hardware implementation becomes essential in many cases where a real time execution, reduced size, or low power system is needed. An efficient hardware architecture is proposed and different optimizations for size and speed are developed: no need for control state machine, reduced computation requirements due to simplifications, etc. Furthermore, t…
Noise Robustness Analysis of Point Cloud Descriptors
2013
In this paper, we investigate the effect of noise on 3D point cloud descriptors. Various types of point cloud descriptors have been introduced in the recent years due to advances in computing power, which makes processing point cloud data more feasible. Most of these descriptors describe the orientation difference between pairs of 3D points in the object and represent these differences in a histogram. Earlier studies dealt with the performances of different point cloud descriptors; however, no study has ever discussed the effect of noise on the descriptors performances. This paper presents a comparison of performance for nine different local and global descriptors amidst 10 varying levels o…