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Mianyang, China

Liao W.B.,China West Normal University | Chen W.,Mianyang Normal University
Naturwissenschaften | Year: 2012

Rensch's rule claims that sexual size dimorphism (SSD) increases with body size when males are larger but decreases with body size when males are smaller. Chinese wood frog Rana chensinensis is a medium-sized species with female-biased size dimorphism. Using data on body size and age in 27 populations covering the full known size range of the species, we tested the consistency of allometric relationships between the sexes with Rensch's rule and evaluated the hypothesis that SSD is largely a function of age differences between the sexes. The results showed that level of female-biased SSD increased with increasing mean size, supporting the inverse of Rensch's rule. Moreover, most of the variation in SSD can be explained in terms of differences in age between the sexes in populations. © Springer-Verlag 2012.

Min L.,China Academy of Engineering Physics | Bo L.,Mianyang Normal University
Journal of Convergence Information Technology | Year: 2012

With the development of computer science, especially the theory of multimedia and digital image processing, image has already become more direct and richer information carrier. It has also become the important source and means for human being to gain and apply information. Image is becoming a more and more important research objective. Image segmentation is very important in image processing technology and is the key step to make image analysis and image manipulating. Image segmentation is very important in image analysis, which needs to separate the related area from the general target to distinguish and analyze an image, and it can make further use of the target, such as characteristic pick-up and measure on the basis of image processing. In this paper, the research status of image segmentation and image segmentation based on graph theory in image technology is firstly stated. Because some classical image segmentation methods based on graph theory, such as normalized cut method, have great complexity and low computational performance for large-scale images, and the stability of the division greatly depends on the choice of parameters, so they can not be used in practice. Therefore, the purpose of this paper is to study a new image segmentation method based on graph theory which has low computational complexity and great practical values. Applying the graph theory to image segmentation can not only reduce computational complexity but also use the advantages of graph theory. Therefore, this paper uses an adaptive weighted formula to improve the generality. A large number of experimental results have shown that this new weighted formula has a good generality and stability compared with other weighted formulae. In order to retain more image details, this paper introduces the multi thresholds image segmentation based on graph theory to solve the problem. With the development of computer science and communication technology, more and more image segmentation methods will be invented to promote the development of the digital image processing.

Wang H.Y.,Mianyang Normal University
Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials | Year: 2011

To study the content of peimisine and total alkaloids in Fritllaria taipaiensis of different growing stage. High performance liquid chromatography coupled with evaporative light scattering detector was employed, and peimisine was separated and quantified upon an Agilent Extend C18 (250 mm x 4.0 mm, 5 microm), using acetonitrile-water-diethylamine as the mobile phase at the flow rate of 1.0 mL min(-1); UV spectrophotometry was used for the determination of total alkaloids. During from two to three years period, the content of peimisine in F. taipaiensis increased with growing stage, from four to six years, it decreased with growing stage; From two to four years, the content of total alkaloids in F. taipaiensis increased with growing stage, from five to six years, it decreased with growing stage. It is suitable to harvest F. taipaienssi of four years growing stage.

Two new oxidovanadium(V) complexes with hydrazone ligands and hydroxamate ligands were synthesized and characterized by IR and 1H NMR spectroscopy, elemental analysis and single crystal X-ray diffraction. The coordination sphere of each V atom is octahedral, constructed from three donor atoms of the hydrazone ligand, two donor atoms of the hydroxamate ligand, and one oxido oxygen. Both complexes show effective catalytic oxidation properties for the oxidation of cyclohexene, cyclopentene and benzyl alcohol using H2O2as primary oxidant.

Jiang S.,Mianyang Normal University
IEEE Transactions on Dependable and Secure Computing | Year: 2016

In this paper, we study a group key agreement problem where a user is only aware of his neighbors while the connectivity graph is arbitrary. In our problem, there is no centralized initialization for users. A group key agreement with these features is very suitable for social networks. Under our setting, we construct two efficient protocols with passive security. We obtain lower bounds on the round complexity for this type of protocol, which demonstrates that our constructions are round efficient. Finally, we construct an actively secure protocol from a passively secure one. © 2004-2012 IEEE.

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