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Guo S.-Z.,North Electronic Systems Engineering Corporation | Li C.,Harbin Engineering University | Lu Z.-M.,Zhejiang University | Qiao Y.-L.,Harbin Engineering University
ICIC Express Letters | Year: 2012

Small-world properties represented as high clustering coefficients and short average path lengths exist in many real-life networks. Small-world models can be classified into two categories: probabilistic and deterministic models. Classical small-world models utilize probabilistic rules to mimic the generation processes of real-life networks, but they cannot provide a vivid understanding of how networks are formed. Therefore, many deterministic models are proposed to provide analytical solutions to topological features. This paper proposes a new deterministic small-world network model which is inspired by the shape of pinwheel. An iteration algorithm is first proposed to generate the pinwheel-shaped model, and then several topological properties are computed analytically to demonstrate the small-world properties of the proposed model. © 2012 ICIC International. Source

Li C.-H.,China Earthquake Administration | Guo S.-Z.,North Electronic Systems Engineering Corporation | Lu Z.-M.,Zhejiang University | Kang G.-Y.,North Electronic Systems Engineering Corporation
ICIC Express Letters | Year: 2011

Eigenvector centrality is one of commonly-used measures to characterize the importance of a node in a complex network. It assigns relative scores to all nodes in the network based on the criterion that links to high score nodes contribute more to the score of the node under discussion than equal links to low score nodes. One of the drawbacks of the eigenvector centrality is that its time complexity is somewhat high. This paper proposes an approximate method to calculate the eigenvector centrality with low complexity and provides experimental results as evidence. © 2011 ICIC International. Source

Zhang Y.,National University of Defense Technology | Guo S.-Z.,North Electronic Systems Engineering Corporation | Lu Z.-M.,Zhejiang University | Luo H.,North Electronic Systems Engineering Corporation
IEICE Transactions on Communications | Year: 2013

Reversible data hiding has been a hot research topic since both the host media and hidden data can be recovered without distortion. In the past several years, more and more attention has been paid to reversible data hiding schemes for images in compressed formats such as JPEG, JPEG2000, Vector Quantization (VQ) and Block Truncation Coding (BTC). Traditional data hiding schemes in the BTC domain modify the BTC encoding stage or BTC-compressed data according to the secret bits, and they have no ability to reduce the bit rate but may reduce the image quality. This paper presents a novel reversible data hiding scheme for BTCcompressed images by further losslessly encoding the BTC-compressed data according to the secret bits. First, the original BTC technique is performed on the original image to obtain the BTC-compressed data which can be represented by a high mean table, a low mean table and a bitplane sequence. Then, the proposed reversible data hiding scheme is performed on both the high mean table and low mean table. Our hiding scheme is a lossless joint hiding and compression method based on 2 × 2 blocks in mean tables, thus it can not only hide data in mean tables but also reduce the bit rate. Experiments show that our scheme outperforms three existing BTC-based data hiding works, in terms of the bit rate, capacity and efficiency. Copyright © 2013 The Institute of Electronics, Information and Communication Engineers. Source

Lu Z.-M.,Zhejiang University | Guo S.-Z.,North Electronic Systems Engineering Corporation
Physica A: Statistical Mechanics and its Applications | Year: 2012

As the deterministic version of the uniform recursive tree (URT), the deterministic uniform recursive tree (DURT) has been intensively studied by Zhang et al. (2008) [21]. They gave several important properties of DURT, including its topological characteristics and spectral properties. Although DURT shows a logarithmic scaling with the size of the network, DURT is not a small-world network since its clustering coefficient is zero. In this paper, we propose a new deterministic small-world network by adding some edges with a simple rule in each DURT iteration, and then give the analytic solutions to several topological characteristics of the model proposed. © 2011 Elsevier B.V. All rights reserved. Source

Huang Z.-L.,Zhejiang University | Guo S.-Z.,North Electronic Systems Engineering Corporation | Lu Z.-M.,Zhejiang University
Information Technology Journal | Year: 2012

This study presents to construct special networks from images and then apply their topological properties to image retrieval. Each input color image is divided into three separate gray-level images in the RGB space. For each gray-level image, we view the 256 gray-levels as nodes and construct the Horizontal Gray-level Co-occurrence Network (HGCN) and Vertical Gray-level Co-occurrence Network (VGCN) by counting the number of horizontal and vertical occurrences for each possible gray-level pair. Based on the obtained six directed weighted networks HGCN-R/G/B and VGCN-R/G/B, we extract their topological features including in-degrees, out-degrees, in-strengths and out-strengths for image retrieval. Simulation results demonstrate the superiority of our features to some existing features in terms of P-R curve. © 2012 Asian Network for Scientific Information. Source

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