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Chen Y.,Mianyang Normal University
Proceedings - 2016 International Conference on Information System and Artificial Intelligence, ISAI 2016 | Year: 2016

The paper studies the thin film of TiO2 nanotube arrays about diameter of 40 μm, which grown by electrochemically second anodization using titanium foil. The structure and compositions of nanotube arrays were characterized by scanning electron microscopy (SEM). Use the same electrolytes solution can grown three samples of TiO2 nanotube arrays under different times. That will be accordingly economize on electrolytes, and save on the time. © 2016 IEEE.

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.

Chen Y.,East China Normal University | Chen Y.,Mianyang Normal University | Compton S.G.,University of Leeds | Liu M.,East China Normal University | Chen X.-Y.,East China Normal University
Molecular Ecology | Year: 2012

Climatic oscillations during the last few million years had well-documented effects on the distributions and genomes of temperate plants and animals, but much less is known of their impacts on tropical and subtropical species. In contrast to Europe and North America, ice-sheets did not cover most of China during glacial periods, and the effects of glacial cycles were less dramatic. Fig trees are a predominantly tropical group pollinated by host-specific fig wasps. We employed partial mitochondrial COI (918 bp) and nuclear ITS2 (462 bp) gene sequences to investigate the genetic structure and demographic histories of the wasps that pollinate the subtropical Ficus pumila var. pumila in Southeastern China. Deep genetic divergence in both mitochondrial (7.2-11.6%) and nuclear genes (1.6-2.9%) indicates that three pollinator species are present and that they diverged about 4.72 and 6.00 Myr bp. This predates the Quaternary ice ages, but corresponds with the formation of the Taiwan Strait and uplifting of the Wuyi-Xianxia Mountains. The three pollinators have largely allopatric distribution patterns in China and display different postglacial demographic histories. Wiebesia spp. 1 and 2 occupy, respectively, the northern and southern regions of the mainland host range. Their populations both underwent significant postglacial spatial expansions, but at different times and at different rates. Wiebesia sp. 3 is largely restricted to northern islands and shows less evidence of recent population expansion. Their mainly allopatric distributions and different demographic histories are consistent with host plant postglacial expansion from three distinct refugia and suggest one mechanism whereby fig trees gain multiple pollinators. © 2012 Blackwell Publishing Ltd.

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.

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.

Liu S.,Mianyang Normal University | Wang H.,Mianyang Normal University
Materials Letters | Year: 2014

WO2 modified LiFePO4/C cathode materials were prepared by a in-situ synthesis method. The structures and compositions of samples were analyzed by XRD, SEM, TEM and EDS. The electrochemical performances of samples were analyzed with charge-discharge test, electrochemical impedance spectroscopy and cyclic voltammetry. WO2 can sufficiently coat on the particles surface of LiFePO4 and does not alter LiFePO4 crystal structure, the WO2 modified LiFePO4/C samples show improved specific capability and decreased charge transfer resistance. Among the investigated samples, the one with 5 wt% WO2 exhibits the best electrochemical performance. This can be mainly attributed to the improvement of electrochemical kinetics by WO2 adding. © 2014 Elsevier B.V.

Jiang S.,Mianyang Normal University
IEEE Transactions on Information Forensics and Security | Year: 2014

We study a keyless authentication problem in a new noisy model, where there is a discrete memoryless channel (DMC) W1 from sender Alice to receiver Bob and a DMC W2 from adversary Oscar to Bob. In addition, there is an insecure noiseless channel between Alice and Bob. Under this model, we characterize the condition under which an authentication from Alice to Bob is possible. We also construct a secure authentication protocol that has an authentication rate approaching infinity. Finally, we prove that the authentication capacity of a noninteractive authentication over binary symmetric channels is exactly 1. This is an interesting result as Shannon capacity of channel W1 is strictly less than 1 while the noiseless channel is completely unreliable. © 2005-2012 IEEE.

Jiang S.,Mianyang Normal University
IEEE Transactions on Information Forensics and Security | Year: 2014

In this paper, we study the commitment over a discrete memoryless channel W : X → Y, where both a sender and a receiver are deterministic. We call it (λh, λb)-secure if it has a hiding error λh and binding error λb. For any c ε (0, log |X|) and any σ ε (0, c), we propose a framework for a message domain of size 2n(c-σ) such that any λh minPX :H(X)=c(I (X; Y)/H(X) - c) with an exponentially (in n) small λb can be achieved, where Y is the output of W with input X and n is the number of channel uses. We show that limc→0 minPX :H(X)=c(I (X; Y)/H(X)) = 0 if and only if a very weak condition on W holds. Note that when limc →0 minPX :H(X)=c(I (X; Y)/H(X)) = 0, we are guaranteed that our framework can commit to a message from a domain of size approximately 2nc for small c with a nearly zero hiding error λh and an exponentially small binding error λb. The price for this is a small commitment rate. We obtain some impossibility results for (λb, λh). For the space M of the commitment input, we show that when |M| = O(1), then (z, o(1))-security is impossible for any z < 1; when |M| = ω(1), then λhmin{α/ γ, 1} and λb = 2-nα is impossible where γ = lim supn→∞(log |M|/n) and α > 0. © 2012 IEEE.

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