Xiaoguo Zhang

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Internet flows characteristics are important reference for network behaviors research. However, there are few latest related studies and comparative analysis on different networks is especially rare. Based on traffic traces from CAIDA and CERNET, this paper presents a detailed and comprehensive comparison on Internet flows characteristics, including the(More)
After evaluating performances of the directional median (DM) filter and the adaptive switching median (ASWM) filter, we propose an adaptive median filter for restoring images by using local texture information in images. It contains two steps: 1) identifying noise pixels; 2) estimating the values of the noise pixels. Firstly, a double-layer window is(More)
NetFlow is a popular technology in network management nowadays. It supports administrators to get various performance metrics. But metric values estimated from NetFlow records may inaccurate in some circumstance. This paper aims at studying the errors of utilized bandwidth measured by NetFlow. At first, packet streams with a specific format were collected(More)
In term of the value of the most noise-free pixels in the local region are close to each other, a new approach for restoring impulse noise corrupted images is proposed. It uses the standard deviation to find out the proximate 5 pixels in the filter window. Subsequently, the weighted mean value and the weighted standard deviation of the 5 pixels are used to(More)
In wireless location area, Taylor Series algorithm is essential to find the solution to minimize the objective function-the sum of squared TDOA measurement remains. This paper proposes a new objective function definition: the sum of squared distance from iterative point to each TDOA hyperbola. Then steepest descent method is used to find the optimized(More)