2,973 research outputs found

    Multiple Moving Object Recognitions in video based on Log Gabor-PCA Approach

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    Object recognition in the video sequence or images is one of the sub-field of computer vision. Moving object recognition from a video sequence is an appealing topic with applications in various areas such as airport safety, intrusion surveillance, video monitoring, intelligent highway, etc. Moving object recognition is the most challenging task in intelligent video surveillance system. In this regard, many techniques have been proposed based on different methods. Despite of its importance, moving object recognition in complex environments is still far from being completely solved for low resolution videos, foggy videos, and also dim video sequences. All in all, these make it necessary to develop exceedingly robust techniques. This paper introduces multiple moving object recognition in the video sequence based on LoG Gabor-PCA approach and Angle based distance Similarity measures techniques used to recognize the object as a human, vehicle etc. Number of experiments are conducted for indoor and outdoor video sequences of standard datasets and also our own collection of video sequences comprising of partial night vision video sequences. Experimental results show that our proposed approach achieves an excellent recognition rate. Results obtained are satisfactory and competent.Comment: 8,26,conferenc

    Heat transport of electron-doped Cobaltates

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    Within the t-J model, the heat transport of electron-doped cobaltates is studied based on the fermion-spin theory. It is shown that the temperature dependent thermal conductivity is characterized by the low temperature peak located at a finite temperature. The thermal conductivity increases monotonously with increasing temperature at low temperatures T << 0.1JJ, and then decreases with increasing temperature for higher temperatures T >> 0.1JJ, in qualitative agreement with experimental result observed from Nax_{x}CoO2_{2} .Comment: 4 pages, 1 fig, corrected typos, accepted for publication in Commun. Theor. Phy

    Study on the limits of all-optical time domain demultiplexing using cross absorption modulation in an electroabsorption modulator

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    A theoretical and experimental assessment of the performance of an all-ticaldemultiplexer based on cross-absorption modulation in an electroabsorption modulator is presented. Simulations are described for demultiplexing from 160 Gbit/s to a 40 or 10 Gbit/s base rate. Experimental results are presented for demultiplexing to a base rate of 10 Gbit/s from an optical time-domain multiplexing rate of 80 with a bit error rate (BER) ,1029 and 160 Gbit/s with a BER ’1027

    Heavy flavor diffusion in weakly coupled N=4 Super Yang-Mills theory

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    We use perturbation theory to compute the diffusion coefficient of a heavy quark or scalar moving in N=4 SU(N_c) Super Yang-Mills plasma to leading order in the coupling and the ratio T/M<<1. The result is compared both to recent strong coupling calculations in the same theory and to the corresponding weak coupling result in QCD. Finally, we present a compact and simple formulation of the Lagrangian of our theory, N=4 SYM coupled to a massive fundamental N=2 hypermultiplet, which is well-suited for weak coupling expansions.Comment: 22 pages, 4 figures; v3: error corrected in calculations, figures and discussion modified accordingl

    Bragg grating assisted all-optical header pre-processor

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    A Bragg grating assisted all-optical header pre-processor based on self-phase modulation in a semiconductor optical amplifier is presented. The operation principle is discussed and demonstrated on packets with an NRZ header at a data rate of 2.5 Gbit/s and a Manchester encoded payload at a data rate of 10 Gbit/s. It is also demonstrated that the header pre-processor improves the performance of an all-optical header processor based on two-pulse correlation in a SLALOM configuration

    A multi-scale framework to predict damage initiation at martensite/ferrite interface

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    Martensite/ferrite (M/F) interface damage largely controls failure of dual-phase (DP) steels. In order to predict the failure and assess the ductility of DP steels, accurate models for the M/F interfacial zones are needed. Several M/F interface models have been proposed in the literature, which however do not incorporate the underlying microphysics. It has been recently suggested that (lath) martensite substructure boundary sliding dominates the M/F interface damage initiation and therefore should be taken into account. Considering the computationally infeasibility of direct numerical simulations of statistically representative DP steel microstructures, while explicitly resolving the interface microstructures and the sliding activity, a novel multi-scale approach is developed in this work. Two scales are considered: the DP steel mesostructure consisting of multiple lath martensite islands embedded in a ferrite matrix, and the microscopic M/F interfacial zone unit cell resolving the martensite substructure. Based on the emerging microscopic damage initiation pattern, an effective indicator for the M/F interface damage initiation is determined from the interface microstructural unit cell response, along with the effective sliding in this unit cell. Relating these two effective quantities for different interface microstructural configurations leads to an effective mesoscale model relating the interface damage indicator to the sliding activity of the martensite island in terms of the mesoscopic kinematics. This microphysics-based M/F interface damage indicator model, which could not be envisioned a-priori, is fully identified from a set of interfacial unit cell simulations, thus enabling the efficient prediction of interface damage initiation at the mesoscale. The capability of the developed effective model to predict the mesoscopic M/F interface damage initiation is demonstrated on an example of a realistic DP steel mesostructure

    All-optical header processor for packet switched networks

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    A serial all-optical header processing technique is presented that is based on the two-pulse correlation principle in a SLALOM configuration. The operation is demonstrated using optical data packets with a packet header at 2.5 Gbit/s and Manchester encoded packet payload at 10 Gbit/s. Experimental evidence is provided in the case of two different output ports. A Bragg grating assisted all-optical header pre-processor based on self-phase modulation in a semiconductor optical amplifier is also presented. It is shown that the header pre-processor improves the performance of the SLALOM-based header processor and that the packet structure can be simplified

    Lag time and parameter mismatches in synchronization of unidirectionally coupled chaotic external cavity semiconductor lasers

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    We report an analysis of synchronization between two unidirectionally coupled chaotic external cavity master/slave semiconductor lasers with two characteristic delay times, where the delay time in the coupling is different from the delay time in the coupled systems themselves. We demonstrate for the first time that parameter mismatches in photon decay rates for the master and slave lasers can explain the experimental observation that the lag time is equal to the coupling delay time.Comment: LaTex, 5 pages, submitted to PRE(R

    Optical flip-flop memory based on ring lasers sharing one active element with feedback through an extended cavity

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    We present a novel optical flip-flop configuration that consists of two unidirectional ring lasers with separate cavities but sharing the same active element unidirectionally. We show that in such a configuration light in the lasing cavity can suppress lasing in the other cavity so that this system forms an optical bistable element. Essential for obtaining the bistability is the presence of an additional feedback circuit that is shared by both lasers. We show experimentally that the flip-flop can be optically set and reset, has a contrast ratio of 40 dB and allows low optical power operation. We also present a model based on roundtrip equations. Good agreement between theory and experiments is obtained

    Nuclear halo and its scaling laws

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    We have proposed a procedure to extract the probability for valence particle being out of the binding potential from the measured nuclear asymptotic normalization coefficients. With this procedure, available data regarding the nuclear halo candidates are systematically analyzed and a number of halo nuclei are confirmed. Based on these results we have got a much relaxed condition for nuclear halo occurrence. Furthermore, we have presented the scaling laws for the dimensionless quantity /R2/R^{2} of nuclear halo in terms of the analytical expressions of the expectation value for the operator r2r^{2} in a finite square-well potential.Comment: 14 pages, 3 figure
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