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Yili, China

Zhang W.,Northeast Normal University | Zhang W.,Yili Normal College | Yang Y.,Northeast Normal University | Li J.,Northeast Normal University
Pakistan Journal of Botany | Year: 2015

Transects were arranged on the shady and sunny slopes, as well as at different elevations of the main, eastern, central, and western gullies in the Wild Walnut Nature Reserve in Xinjiang, China to survey a large sample of Juglans mandshurica. The structures of height class and diameter at breast height (DBH) class were used to represent age structure to compare and analyze the dynamics of the population quantity of J. mandshurica in different habitats. Results showed that J. mandshurica population comprises numerous young seedlings, which develop into young plants with a high death rate. The number of adult plants is stable. J. mandshurica population is r-strategists in the young stage, and k-strategists supplemented by r-strategists in the juvenile and subsequent stages. The structures of height class and DBH class fluctuate at different slope aspects and elevations. The growth of young seedlings into adult plants is discontinuous. Tree height and DBH are relatively uniform in the same age class, and the coefficient of variation is independent of slope aspect and elevation. The maximum numbers of age classes in J. mandshurica population with different height and DBH classes differ at three elevations. Lowand medium-age classes are dominant in all situations. That is, population is mainly composed of juvenile and adult trees, and age structure is classified as a growth type. Without strong external interference, J. mandshurica population will maintain its superior position in the community. © 2015, Pakistan Botanical Society. All rights reserved. Source

Lu C.,Yili Normal College | Liu W.,Curtin University Australia
Neurocomputing | Year: 2012

In this paper we propose a new face recognition method based on two-dimensional locality preserving projections (2DLPP) in frequency domain. For this purpose, we first introduce the two-dimensional locality preserving projections. Then the 2DLPP in frequency domain is proposed for face recognition. In fact, two dimensional discrete cosine transform (2DDCT) is used as a pre-processing step and it transforms the face image signals from spatial domain into frequency domain aiming to reduce the effects of illumination and pose changes in face recognition. Then 2DLPP is applied on the upper left corner blocks of the 2DDCT transformed matrices, which represent main energy of each original image. For demonstration, the Olivetti Research Laboratory (ORL), YALE, FERET and YALE-B face datasets are used to compare the proposed approach with the conventional 2DLPP and 2DDCT approaches with the nearest neighborhood (NN) classifier. The experimental results show that the proposed 2DLPP in frequency domain is superior over the 2DLPP in spatial domain and 2DDCT itself in frequency domain. © 2012. Source

Liang Y.,Dalian University of Technology | Liang Y.,Yili Normal College | Wang X.,Dalian University of Technology
Pramana - Journal of Physics | Year: 2013

It is proved that the maximum eigenvalue sequence of the principal submatrices of coupling matrix is decreasing. The method of calculating the number of pinning nodes is given based on this theory. The findings reveal the relationship between the decreasing speed of maximum eigenvalue sequence of the principal submatrices for coupling matrix and the synchronizability on complex networks via pinning control. We discuss the synchronizability on some networks, such as scale-free networks and small-world networks. Numerical simulations show that different pinning strategies have different pinning synchronizability on the same complex network, and the synchronizability with pinning control is consistent with one without pinning control in various complex networks. © Indian Academy of Sciences. Source

Liang Y.,Yili Normal College | Wang X.,Dalian University of Technology
Proceedings of the 2012 4th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2012 | Year: 2012

In this paper, we propose one adaptive pinning synchronization scheme in complex dynamical networks, whose adaptive law is simple in form. When a nonlinear vector field meets different conditions, we prove that the scheme is synchronous and that the synchronous solution is locally and globally asymptotically stabile. We analyze the process of using maximum eigenvalues of low matrix to judge pinning synchronization, and give one method to calculate the number of pinning nodes. At last, three numerical simulations are given to verify the effectiveness of the proposed scheme. The first two examples show relations between maximum eigenvalues of the principal submatriecs and the number of pinning nodes under the conditions of three pinning strategies in a scale-free network and under the conditions of the random pinning strategy in a nearest-neighbor network, respectively, and the last one shows effectiveness of the adaptive pinning synchronization by selecting pinning nodes randomly in a scale-free network. Copyright © 2012 by The Institute of Electrical and Electronics Engineers, Inc. Source

Lu C.,Dalian University | Lu C.,Yili Normal College | An S.,Curtin University Australia | Liu W.,Curtin University Australia | Liu X.,Dalian University
Journal of Signal Processing Systems | Year: 2011

Two Dimensional Linear Discrimination Analysis (2DLDA) is an effective feature extraction approach for face recognition, which manipulates on the two dimensional image matrices directly. However, some between-class distances in the projected space are too small and this may produce a large erroneous classification rate. In this paper we propose a new 2DLDA-based approach that can overcome such drawback for the existing 2DLDA. The proposed approach redefines the between-class scatter matrix by putting a weighting function based on the betweenclass distances, and this will balance the between-class distances in the projected space iteratively. In order to design an effective weighting function, the betweenclass distances are calculated and then used to iteratively change the between-class scatter matrix, which eventually leads to an optimal projection matrix. Experimental results show that the proposed approach can improve the recognition rates on benchmark data-bases such as the ORL database, the Yale database, the YaleB database and the Feret database in comparison with other 2DLDA variants. © Springer Science+Business Media, LLC 2010. Source

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