Liu Q.,Chongqing Technology and Business University
Zhongguo Jiguang/Chinese Journal of Lasers | Year: 2010
Applying the condition of electromagnetic wave restricted in horizontal direction, the conditions that each mode should satisfy are concluded from the one-dimensional rectangle doping photonic crystal. The dependences of defect modes on the mode quantum number and doping thickness are obtained for TE wave and TM wave. These results can be used to design multi-channel filter with frequency tuning.
Jiang Y.-K.,Chongqing Technology and Business University
Journal of Molecular Modeling | Year: 2010
Three-dimensional quantitative structure-activity relationship (3D-QSAR) and molecular docking studies were carried out to explore the binding of 73 inhibitors to dipeptidyl peptidase IV (DPP-IV), and to construct highly predictive 3D-QSAR models using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). The negative logarithm of IC50 (pIC50) was used as the biological activity in the 3D-QSAR study. The CoMFA model was developed by steric and electrostatic field methods, and leave-one-out cross-validated partial least squares analysis yielded a cross-validated value (r2cv) of 0.759. Three CoMSIA models developed by different combinations of steric, electrostatic, hydrophobic and hydrogen-bond fields yielded significant r 2cv values of 0.750, 0.708 and 0.694, respectively. The CoMFA and CoMSIA models were validated by a structurally diversified test set of 18 compounds. All of the test compounds were predicted accurately using these models. The mean and standard deviation of prediction errors were within 0.33 and 0.26 for all models. Analysis of CoMFA and CoMSIA contour maps helped identify the structural requirements of inhibitors, with implications for the design of the next generation of DPP-IV inhibitors for the treatment of type 2 diabetes. © Springer-Verlag 2010.
Chen S.-J.,Chongqing Technology and Business University |
Li L.,Southwest University
Nonlinear Analysis: Real World Applications | Year: 2013
In this paper we study the following nonhomogeneous Kirchhoff equation -(a+b∫RNδu2dx)Δu+V(x)u=f(x,u)+h(x), inRN, where f satisfies the Ambrosetti-Rabinowitz type condition. Under appropriate assumptions on V, f and h, the existence of multiple solutions is proved by using the Ekeland's variational principle and the Mountain Pass Theorem in critical point theory. © 2012 Elsevier Ltd. All rights reserved.
Yuan L.,Chongqing Technology and Business University |
Lu Y.Y.,City University of Hong Kong
Optics Express | Year: 2013
Nonlinear optical effects can be enhanced by photonic crystal microcavities and be used to develop practical ultra-compact optical devices with low power requirements. The finite-difference time-domain method is the standard numerical method for simulating nonlinear optical devices, but it has limitations in terms of accuracy and efficiency. In this paper, a rigorous and efficient frequency-domain numerical method is developed for analyzing nonlinear optical devices where the nonlinear effect is concentrated in the microcavities. The method replaces the linear problem outside the microcavities by a rigorous and numerically computed boundary condition, then solves the nonlinear problem iteratively in a small region around the microcavities. Convergence of the iterative method is much easier to achieve since the size of the problem is significantly reduced. The method is presented for a specific two-dimensional photonic crystal waveguide-cavity system with a Kerr nonlinearity, using numerical methods that can take advantage of the geometric features of the structure. The method is able to calculate multiple solutions exhibiting the optical bistability phenomenon in the strongly nonlinear regime. © 2013 Optical Society of America.
Liu Q.-N.,Chongqing Technology and Business University
Guangzi Xuebao/Acta Photonica Sinica | Year: 2012
In order to obtain resonance theory of 1D doping photonic crystal, a resonant cavity model is set up and the analytical formulas of the defect mode frequency of 1D doping photonic crystal is deduced by resonance conditions of the resonant cavity. The physical mechanism of the defect mode of 1D doping photonic crystal is explained. The use of analytical formulas for the variation, which defect mode frequency with the incident angle and thickness of impurities and refractive index of impurities changes, is studied. Resonance theory results and characteristic matrix method results are compared and their results are the same, and the resonance theory is the right way. The resonance theory to analyze variable relationship is convenient, which makes up the deficiency of the numerical calculation method of 1D photonic crystal.