Visual Computing and Virtual Reality Key Laboratory of Sichuan Province

China

Visual Computing and Virtual Reality Key Laboratory of Sichuan Province

China

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Yang J.,Sichuan Normal University | Yang J.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Liu Y.L.,Sichuan Normal University | Feng C.S.,Sichuan Normal University | Zhu G.Q.,Sichuan Normal University
Genetics and molecular research : GMR | Year: 2016

Biologists and scientists can use the data from Alzheimer's disease (AD) gene expression microarrays to mine AD disease-related genes. Because of disadvantages such as small sample sizes, high dimensionality, and a high level of noise, it is difficult to obtain accurate and meaningful biological information from gene expression profiles. In this paper, we present a novel approach for utilizing AD microarray data to identify the morbigenous genes. The Fisher score, a classical feature selection method, is utilized to evaluate the importance of each gene. Genes with a large between-classes variance and small within-class variance are selected as candidate morbigenous genes. The results using an AD dataset show that the proposed approach is effective for gene selection. Satisfactory accuracy can be achieved by using only a small number of selected genes.


Gu Q.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Gu Q.,Sichuan Normal University
Advanced Materials Research | Year: 2011

With emergence of online virtual reality applications, the 3D data of virtual scenes are available to heterogeneous end user devices with relatively limited computing power, resolution and transmission rate. Still, many virtual scenes created by expert developers are composed of complex 3D data models with huge number of geometry primitives and appearence elements. This complexity can cause a lot of problems when the scenes are deployed on the limited access devices. To address this issue, we propose a virtual scene adaptation framework which is able to perform the transformation of given complex 3D model into new forms with less geometric and appearance data Through the framework, complex virtual scenes are connected with real-world semantics and are preprocessed with selected optimization strategies based on the semantic features matching client devices' capabilities before deployment. © (2011) Trans Tech Publications, Switzerland.


Hou B.-P.,Sichuan Normal University | Hou B.-P.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Chen J.,Sichuan Normal University | Pan Y.-M.,Sichuan Normal University
European Physical Journal D | Year: 2014

The effects of decoherence due to dephasing and incoherent population exchange on the cross-Kerr nonlinearity are investigated. In the linear optical behavior, the incoherent population exchange suppresses the linear resonance such as the Autler-Townes absorption and the electromagnetically induced transparency in the same manner as the dephasing. While in the cross-Kerr optical responses these two decoherence mechanisms affect the nonlinearity in different ways. The dephasing enhances the nonlinear absorption at resonance, while the incoherent population exchange leads to cross-nonlinear gain and also broadens its spectrum. In particular, the large cross-Kerr nonlinearity without nonlinear absorption can be realized by suitably adjusting the incoherent population exchange. Additionally, the dependence of y-intercepts of absorption or dispersion curves without control field on the population exchange rate can be used to estimate the incoherent population exchange rate of the system. The results provided here are useful not only for illustrating distinct physical mechanisms of these two kinds of decoherence in nonlinear optics, but also for potential applications of cross-Kerr nonlinearity in quantum information processing. © 2014 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.


Ding J.L.,Sichuan Normal University | Hou B.P.,Sichuan Normal University | Hou B.P.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province
Optics Communications | Year: 2011

The interaction of a collection of N four-level tripod configuration atoms with two orthogonally polarized probe fields is investigated. Under the condition of electromagnetically induced transparency (EIT), we calculate the squeezing and entanglement spectra of the output probe fields. By analyzing the output spectrum, we find that the squeezing and entanglement of the probe fields can be well-preserved after passing through the optically thick medium. Additionally, the effects of the ground state dephasing rates of the atoms on the entanglement and squeezing of the output two-mode squeezed fields are investigated. It is shown that the dephasing rates will degrade the entanglement and squeezing, and these quantum properties can be lost when the dephasing rates increase up to a certain value. This will be useful in the quantum computation and quantum communication. © 2011 Elsevier B.V. All rights reserved.


Chen W.-L.,University of Sichuan | Chen W.-L.,Sichuan Normal University | Chen W.-L.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | He X.-H.,University of Sichuan | And 2 more authors.
Journal of Information Science and Engineering | Year: 2012

A feature-based sequence-to-sequence alignment method was proposed by Caspi et al., which can align multiple sequences in space-time. But this method can not be very effective and precise in spatial alignment, due to a small number of moving objects in the scene, limited coverage of the trajectories and the short temporal duration of the trajectories. In order to solve this problem, we proposed a new sequence-to-sequence alignment method, combining the method proposed by Caspi et al. with a feature-based image registration method. In this paper, we made a comparison between our method and that of Caspi et al. Experimental results show that the presented method improves alignment precision both on X-axis orientation and on Y-axis orientation. The PSNR value is approximately improved by 13.5dB. At the same time, the time needed by Our-method will be slightly increased but can be ignored. When the results of the alignment are applied in space-time super-resolution reconstruction, the effect also proves the validity of our-method.


Yang J.,Sichuan Normal University | Yang J.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Liu Y.L.,Sichuan Normal University | Feng C.S.,Sichuan Normal University | Zhu G.Q.,Sichuan Normal University
Genetics and Molecular Research | Year: 2016

Biologists and scientists can use the data from Alzheimer’s disease (AD) gene expression microarrays to mine AD disease-related genes. Because of disadvantages such as small sample sizes, high dimensionality, and a high level of noise, it is difficult to obtain accurate and meaningful biological information from gene expression profiles. In this paper, we present a novel approach for utilizing AD microarray data to identify the morbigenous genes. The Fisher score, a classical feature selection method, is utilized to evaluate the importance of each gene. Genes with a large between-classes variance and small within-class variance are selected as candidate morbigenous genes. The results using an AD dataset show that the proposed approach is effective for gene selection. Satisfactory accuracy can be achieved by using only a small number of selected genes. © FUNPEC-RP.


Li X.,Sichuan Normal University | Li C.,Sichuan Normal University | Li C.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Ma L.,Sichuan Normal University
Proceedings - 2014 7th International Symposium on Computational Intelligence and Design, ISCID 2014 | Year: 2015

Online shopping has become an important and popular way of life. With the rapid C2C platform development, the credit problem in online shopping was being discussed. Serious loss of credit will leads to bad online business environment. However, till now lots of researchers just focus on seller reputation model to solve credit problem, thus buyer reputation model is seldom being considered. To solve the above problem, we proposed a Computational Buyer Reputation Model for C2C e-Commerce platform, i.e. CBRM. Five buyer reputation indicators, including transactions amount, seller ratings, buyer operations, chargeback ratio and real name authentication, were integrated into CBRM. By using AHP to distribute various indicator weights, we can obtain numeric value of buyer reputation. Therefore, these values can be used for sellers to choose appropriate buyers to deal with. Experiment results showed the efficiency and effectiveness of CBRM. © 2014 IEEE.


Mu J.J.,Sichuan Normal University | Hou B.P.,Sichuan Normal University | Hou B.P.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province
Optik | Year: 2013

The output squeezed spectrum of the output two modes from a cavity QED system which is embedded by a four-level atom driven by two classical fields are calculated. The effects of the cavity decay rates, relative phase between two classical fields, and effective coupling constants between the atom and the cavity on the entanglement and squeezing of the two cavity modes are investigated. It is shown that the depth of the squeezing or entanglement spectrum is insensitive to the cavity decay rates while its width is dependent on the cavity decay rates and the coupling constants. In particular, the squeezing or entanglement spectrum including their maximal values and widths is remarkably affected by the relative phase between the classical fields. It is found that the output spectrum varies with the relative phase in a cosine-like behavior with a period of 2π. The results can indicate how to suitably adjust the relative phase for acquiring maximal squeezing or perfect entanglement for the two cavity fields. This will be useful in quantum communication and computation. © 2013 Elsevier GmbH.


Ding J.L.,Sichuan Normal University | Hou B.P.,Sichuan Normal University | Hou B.P.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Wang S.J.,University of Sichuan
Journal of Physics B: Atomic, Molecular and Optical Physics | Year: 2010

We investigate the propagation and storage of a squeezed vacuum as the probe light in a collection of N four-level tripod configuration atoms under the condition of single or double electromagnetically induced transparency (EIT). The squeezing of the probe light is well preserved in both the single transparency channel and the double transparency one. On the other hand, the effects of the ground state dephasing rates on the propagation and storage of the squeezed vacuum are investigated. It is found that the maximum squeezing at the transparency points is suppressed by the dephasing rates in single or double EIT. Meanwhile, the mapping of the squeezing of the probe light onto the atomic ground coherences or onto the two atomic dark-state polaritons is also studied. In the absence of the Langevin atomic noise, the quasi-ideal squeezing transfer between the squeezed vacuum and the atomic ground coherences or the dark-state polaritons can be realized in such a system. When considering the Langevin atomic noise, the quantum characteristics of the atomic coherences at resonance are submerged by the Langevin noise, while in the scenario of the dark-state polariton, it is found that squeezing transfer onto one polariton is damaged, but the squeezing transfer onto the other polariton survives even in the presence of the Langevin noise. © 2010 IOP Publishing Ltd.


Li X.-N.,Sichuan Normal University | Li X.-N.,Visual Computing and Virtual Reality Key Laboratory of Sichuan Province | Wu Z.-H.,Sichuan Normal University | Xing H.-Y.,Sichuan University
Applied Mechanics and Materials | Year: 2014

In classic radial sampling scheme, angle intervals between adjacent straight sampling lines are the same. And so the coherence between the sampling matrix and the sparse matrix is high. Many pseudo-shadows will occur on the reconstructed image. For this problem, we put forward a novel sampling scheme in which the scan lines are placed in the manner of golden section angle interval. In the resulting sampling matrix, the scan lines scatter randomly on the whole. Experimental results demonstrate that the algorithm proposed in this paper has lower correlation coefficient between sampling matrix and sparse matrix than classic radial sampling scheme and random radial sampling scheme. Image can be accurately reconstructed by collecting less data than the other two schemes. © (2014) Trans Tech Publications, Switzerland.

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