The contourlet transform has the benefit of efficiently capturing the oriented geometrical structures of images. In this paper, by incorporating the ideas of Stein’s Unbiased Risk Estimator (SURE) approach in Nonsubsampled Contourlet Transform (NSCT) domain, a new image denoising technique is devised. We utilize the characteristics of NSCT coefficients in high and low subbands and apply SURE sh...

MRI is one of the most powerful techniques to study the internal structure of the body. MRI image quality is affected by various noises. Noises in MRI are usually thermal and mainly due to the motion of charged particles in the coil. Noise in MRI images also cause a limitation in the study of visual images as well as computer analysis of the images. In this paper, first, it is proved that proba...

In this paper, we study the impact of low-quality node on the performance of incremental least mean square (ILMS) adaptive networks. Adaptive networks involve many nodes with adaptation and learning capabilities. Low-quality mode in the performance of a node in a practical sensor network is modeled by the observation of pure noise (its observation noise) that leads to an unreliable measurement....

We investigate power estimation on a random noise from measurements taken by one-bit quantizers, with an efficacy assessed by the Fisher information. In isolated quantizers, an optimal tuning of the quantization threshold exists to maximize the estimation efficacy. When the quantizers are assembled in parallel arrays, no specific tuning of the quantization threshold is any longer required. Inst...

This study proposes an effective noise estimation method for robust speech recognition in time-varying noise conditions. The proposed noise estimation scheme employs the Variation Model Composition (VMC) method, where multiple noise models are generated by selectively applying perturbation factors to the mean parameters of a basis noise model. The noise estimate is obtained by using the posteri...

Introduction: The position estimation in gamma detection system will have constant misplacements which can be corrected in the calibration procedure. In the pixelated crystal uniformly irradiation of detector will produce irregular shape due to position estimation errors. This image is called flood field image and is used to calibrate the position estimation. In this work we pr...

introduction hippocampus is a well-defined brain region involved in learning and memory. in spite of the existing reports on hippocampal-dependent memory impairment due to noise stress, to our knowledge, there is no study on the effect of noise stress on the size of hippocampus. the present study aimed to investigate the likely effects of chronic noise exposure on learning and the size of rat h...

We describe a novel algorithm for the estimation of the colored noise level in audio signals with mixed noise and sinusoidal components. The noise envelope model is based on the assumptions that the envelope varies slowly with frequency and that the magnitudes of the noise peaks obey a Rayleigh distribution. Our method is an extension of a recently proposed approach of spectral peak classificat...

Several approaches have been introduced in literature for active noise control (ANC)systems. Since Filtered-x-Least Mean Square (FxLMS) algorithm appears to be the best choice as acontroller filter. Researchers tend to improve performance of ANC systems by enhancing andmodifying this algorithm. This paper proposes a new version of FxLMS algorithm. In many ANCapplications an online secondary pat...