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This paper proposes an image watermarking scheme for copyright protection based on Independent Component Analysis (ICA). In the suggested scheme, we divide the original image into blocks and use the ICA to project the image into a basis with its components as statistically independent as possible. The data embedding is carried out in cumulative form in the ICA basis and also the ICA is used for watermark...
Tow ship noise is a typical multi-path directional interference, and the receiving response of which on towed line array is worthy of in-depth study. Firstly, the sea trial data was analyzed to summarize the tow ship noise characteristics. Then the underwater acoustic field of tow ship noise was modeled to achieve the power distribution of the noise. Finally an important result was obtained, that...
Ultrasound images are very noisy. Along with system noise, a significant noise source is the speckle phenomenon caused by interference in the viewed object. The noise of ultrasound image was always deemed as multiplicative noise, but the present multiplicative noise models are not fitting for it very well, because the noise is more complex than the simple multiplicative one. So we should consider...
Tow ship noise is a typical directional interference for towed line array sonar, nonstationary process with several characteristic properties, such as multi-path and angle dispersion, which greatly add the difficulty to cancel or suppress the noise. Empirical Mode Decomposition (EMD) is a novel method used for processing nonlinear and nonstationary signals. Finite Intrinsic Mode Functions (IMFs) are...
Multiscale Geometry Analysis consistent with the best features of the image representation, is effective for high dimensional function approximation and can use the image of the geometric regularity. In this article, we will mainly discuss the transformation of the Beam let based on Multiscale Geometry Analysis, formulate its theoretical basis, and by Matlab simulation results show the advantages...
In this paper we present a novel method for high quality real-time video enhancement; it improves the sharpness and the contrast of video streams, and simultaneously suppresses noise. The method is comprised of three main modules: (1) noise analysis, (2) spatial processing, based on a new multi-scale pseudo-bilateral filter, and (3) temporal processing that includes robust motion detection and recursive...
Networks are very important in many fields of machine learning research. Within networks research, inferring the structure of unknown networks is often a key problem; e.g. of genetic regulatory networks. However, there are very few well-known biological networks, and good simulation is essential for validating and evaluating novel structural inference techniques. Further, the importance of large,...
We generalize algorithms from computational learning theory that are successful under the uniform distribution on the Boolean hypercube {0,1}n to algorithms successful on permutation invariant distributions. A permutation invariant distribution is a distribution where the probability mass remains constant upon permutations in the instances. While the tools in our generalization mimic those used for...
There will be different stable states or attractors in ecosystem under the same external conditions. In this paper, one stochastic logistic model under external fluctuations was established. The existence of the alternative attractors and regime shift are investigated. Also, the mean first passage time is studied using stochastic dynamics theory. Results showed that there are different stable attractors...
The motion of an over damped Brownian particle in a bistable potential is analyzed from the perspective of stochastic energetics. Without noise and with the increase of the input amplitude, the work done by the periodic force increases first and reach the maximum, then decreases sharply, and finally increases. Only when the work is more than the height of the barrier and equal to the barrier height...
The rapid development of networks such as internet, intranet, wireless communication etc., and multimedia techniques has emphasized on the need for copyright protection, authentication and identification and secret sharing of information. Visual cryptography is a secret sharing scheme where a secret binary image (SI) is encoded into n shares of random binary patterns. If the shares are xeroxed onto...
In this paper we propose a new algorithm for the least square fitting of ellipses from scattered data. Originally based on the one proposed by Fitzgibbon et Al in 1999, our procedure is able to overcome the numerical instability of that algorithm. We test our approach versus the latter and another approach with different ellipses. Then, we present and discuss our results.
In this work, the authors discuss the design of two low noise amplifiers (LNA) based on 1 μm gate-length pHEMT InP transistors and using two different topologies. Designed for radio astronomy applications, the first is a cascode circuit with a maximum gain of 15 dB and noise figure of 0.6 dB, while the second is a 2-stage cascaded amplifier with 27 dB of gain and 0.63 dB of noise figure. The two amplifiers...
This paper mainly introduces the edge extraction algorithm of thenar palm print image based on wavelet modulus maxima multi-scale. First, some classical edge detection operators and the Hough transform are introduced. And then the paper focuses on the wavelet modulus maxima multi-scale edge detection algorithm. In this algorithm, a multi-scale Gaussian edge detector is constructed. According to cross-scale...
To collect neuronal activity data from awake, behaving freely animals, we developed miniaturized telemetry recording system. The integrated system consists of four major components: (1) microelectrodes and micro-driver assembly; (2) analog front end (AFE); (3) Programable system on chip (PSoC); (4) Radio transceiver and the LabVIEW used as a platform for the graphic user interface. The result showed...
We investigate how firing behavior of FitzHugh-Nagumo neuron depends on the intensity of Gaussian white noise. It is found that there exists an intermediate range intensity of noise where the firing behavior of neuron is induced and enhanced. To quantitatively study the firing degree of the neuron, the average number of firing spiking is introduced to measure the frequency of the firing patterns....
In this paper, we propose an efficient noise reduction method that can be used to reduce speckle and jointly enhancing the edge information, rather than just inhibiting smoothing. In this method speckle is removed by filtering of band pass ultrasound images in Laplacian pyramid domain by using mixed PDE based nonlinear diffusion. In each pyramid layer, a gradient threshold is estimated automatically...
Wave atom transform is a new multi-resolution technique, which has the ability to adapt to arbitrary local directions of a pattern, and to sparsely represent anisotropic patterns aligned with the axes. In this paper, a de-noising technique is proposed to remove the rician noise from Magnetic Resonance Images using wave atom shrinkage. It is well known that the noise in magnetic resonance imaging has...
The usage of multi-beam antenna in passive millimeter wave imaging system reduces the time of imaging, but this system structure leads to striping in the image acquired. By analyzing the characteristics of passive millimeter wave image and the spectrum distribution of striping noise, use a modified Butterworth low pass filter to remove striping in frequency domain. Confirm the cut-off frequency of...
This paper describes a graphical method for the optimization of Quadrature Voltage Controlled Oscillators (QVCOs) based on the coupling of two LC-tank VCO. A three-dimensional phase noise analysis diagram and graphical optimization approach is presented, to optimize QVCO phase noise while satisfying design constraints such as power dissipation, tank amplitude, tuning range and start up condition....
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