The U1 matrix and extreme U1 matrix were successfully used to study quadratic doubly stochastic operators by R. Ganikhodzhaev and F. Shahidi [Linear Algebra Appl., 2010, 432： 24-35], where a necessary condition for a...
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The U1 matrix and extreme U1 matrix were successfully used to study quadratic doubly stochastic operators by R. Ganikhodzhaev and F. Shahidi [Linear Algebra Appl., 2010, 432： 24-35], where a necessary condition for a U1 matrix to be extreme was given. S. Yang and C. Xu [Linear Algebra Appl., 2013, 438： 3905-3912] gave a necessary and sufficient condition for a symmetric nonnegative matrix to be an extreme U1 matrix and investigated the structure of extreme U1 matrices. In this paper, we count the number of the permutation equivalence classes of the n × n extreme U1 matrices and characterize the structure of the quadratic stochastic operators and the quadratic doubly stochastic operators.
For the defect in describing affine and blur invariable of scale-invariant feature transform (SIFT) at large viewpoint variation, a new object recognition method is proposed in this paper, which used maximally stable ...
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Considering the photonic crystal structure is critical to the future development of communication, the enthusiasm for the research of photonic crystal is always high. In this paper, the nonlinear finite-difference tim...
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ISBN:
(纸本)9781450353489
Considering the photonic crystal structure is critical to the future development of communication, the enthusiasm for the research of photonic crystal is always high. In this paper, the nonlinear finite-difference time-domain method is used to analyze the transmission characteristics of one-dimensional photonic crystal structure. As the center frequency of the optical pulse approaches is closed to the photonic band gap, the group velocity dispersion of the light pulse increases. In addition, soliton waves can be generated in the structure with the introduction of Kerr nonlinear. And soliton waves can make outstanding contributions to the accurate transmission of information.
At present, in related image processing field, the fuzzy set theory has also gained more successful applications to some extent. The image processing based on the fuzzy theory is an important research area. The inform...
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At present, in related image processing field, the fuzzy set theory has also gained more successful applications to some extent. The image processing based on the fuzzy theory is an important research area. The information loss brought by 3D object projection in 2D image plane makes the image have the ambiguity exist in essence, thus there exists ambiguity when defining image characteristics such as the border, area and texture, therefore, because of the complexity of the image itself, uncertainty and inaccuracy or ambiguity may occur in the different stages of the processing. The algorithm in this paper improves the degree of membership function to make it suitable for the image fuzzy enhancement. The membership function curve is S-shaped, and at the inflection point, the function value on the left side drops rapidly while the function value on the right side rapidly rises. There is certain symmetry about the inflection point, and the function inflection point position can be decided by changing function parameters, and better enhancement effect can be gained by a small amount of iteration. By the experimental simulation, it is verified that the enhanced color image by adopting the method in this paper is bright in color on the visual effect with moderate increasing proportion of brightness and contrast, and best color maintaining performance and minimum chromaticity change, and also the image information entropy is improved when compared with the original image data.
This paper presents a novel image fusion method based on nonsubsampled shearlet transform (NSST) and block-based random image sampling for infrared and visible images. In the method, the NSST is firstly performed on e...
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This paper presents a novel image fusion method based on nonsubsampled shearlet transform (NSST) and block-based random image sampling for infrared and visible images. In the method, the NSST is firstly performed on each of the source images to obtain their low frequency and high frequency subbands coefficients. Then the low frequency coefficients are fused by combing the block-based random image sampling and the sliding widow technique, while the high frequency coefficients are fused using classical absolute value maximum choosing rule. The fused image is reconstructed though performing the inverse NSST. The experiments are carried out on five pairs of infrared and visible images using five traditional fusion methods to verify the effectiveness and efficiency of the proposed method and by comparing the fused results visually and objectively it is demonstrated that the proposed fusion method is competitive or even superior to the other wellknown methods.
Image enhancement, as a means of digital image processing, often is fuzzy. Based on defects of excessive enhancement and insufficient detail enhancement existing in the traditional image enhancement method, this paper...
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Image enhancement, as a means of digital image processing, often is fuzzy. Based on defects of excessive enhancement and insufficient detail enhancement existing in the traditional image enhancement method, this paper proposes a self-adaptive image enhancement method based on variable fuzzy sets, and such method can, according to the image's gray-scale properties, introduce the relative gray-scale level of the pixel as the fuzzy feature, and adopt the improved membership function to conduct the fuzzy enhancement, thus avoiding the loss of a great deal of gray-scale information after the enhancement. The paper also introduces the selection of optimal parameters, ensures the quality of the image enhanced and improves the feasibility and efficiency of this algorithm. This algorithm, on the basis of keeping the image's original brightness, enhances the image details at the same time. Experimental results show that such algorithm can obtain good visual effect and more obvious detail information.
The dual of the Kasami code of length q2 − 1, with q a power of 2, is constructed by concatenating a cyclic MDS code of length q + 1 over Fq with a Simplex code of length q − 1. This yields a new derivation of the wei...
In this paper,we consider a wireless ad hoc network consisting of multiple source nodes transmitting to their respective destinations,where an eavesdropper attempts to intercept their *** propose an optimal transmissi...
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In this paper,we consider a wireless ad hoc network consisting of multiple source nodes transmitting to their respective destinations,where an eavesdropper attempts to intercept their *** propose an optimal transmission scheduling scheme to defend against the eavesdropper,where a source node having the highest secrecy rate is scheduled to access the wireless medium for transmitting to its destination in an opportunistic *** be specific,the secrecy rate between a pair of the source and destination in the presence of an eavesdropper varies temporally due to the wireless fading *** proposed optimal transmission scheduling scheme opportunistically selects a source node with the highest secrecy rate to transmit its data for the sake of maximizing the security of the ad hoc network against eavesdropping *** comparison purposes,we also consider the conventional round-robin scheduling as a benchmark,where multiple source nodes take turns in accessing their shared wireless medium for transmitting to their respective *** derive closed-form secrecy outage probability expressions of both the round-robin scheduling and the proposed optimal scheduling schemes over Rayleigh fading *** results show that the proposed transmission scheduling scheme outperforms the conventional round-robin method in terms of its secrecy outage ***,upon increasing the number of source-destination pairs,the secrecy outage probability of the round-robin scheme keeps unchanged,whereas the secrecy outage performance of the proposed transmission scheduling significantly improves,showing the security benefits of exploiting transmission scheduling for protecting wireless ad hoc networks against eavesdropping.
The community detection was performed from the perspective of links, and we proposed an inhibition method against social network worms. Firstly, a community detection algorithm was proposed, which based on link cluste...
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The community detection was performed from the perspective of links, and we proposed an inhibition method against social network worms. Firstly, a community detection algorithm was proposed, which based on link clustering, and we got related link incremental information through the network structure information at various time points. In order to obtain the link communities, we adopted an improved link partition density function to dispose the link incremental information. Next, we gave three selection strategies of key nodes in community and proposed corresponding worm inhibition method. Finally, on the basis of real web data sets, we applied community detection and worm inhibition experiments to prove validity of algorithm in this paper.
The definitions of the Lee complete ρ weight enumerator and the exact complete ρ weight enumerator over Mn×s (F2[u, v]{uk, v2, uv-vu}) are introduced, and the MacWilliams identities with respect to the RT metri...
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