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Yunlong, China

Xiong R.,PLA University of Science and Technology | Xiong R.,Engineer Academy of PLA | Gao C.,PLA University of Science and Technology | Chen B.,PLA University of Science and Technology | And 2 more authors.
IEEE Antennas and Propagation Magazine | Year: 2014

A uniform two-step method is proposed for the Finite-Difference Time-Domain (FDTD) analyses of the coupling of both long and short apertures with zero or finite depth. The aperture-field singularity is first studied in the form of the field distribution and the aperture coefficients derived from the numerical integral of the related fields. The dramatic field singularity and the coefficients are mainly determined by the aperture's width and depth, and also by the aperture's end-edge effect. To provide an accurate modeling of the aperture without requiring huge computational-resource usage, a high-resolution standard FDTD simulation of the aperture end-edge area is used at the first step, and then the electromagnetic field singularity is used to derive the aperture coefficients from a numerical integral. At the second step, the coefficients are fully included into the contour-path laws to derive the FDTD updating equations for the fields near the aperture. Numerical results validated that the proposed method is an efficient simulation of the aperture coupling. © 1990-2011 IEEE. Source


Xiong R.,Engineer Academy of PLA | Xiong R.,PLA University of Science and Technology | Chen B.,PLA University of Science and Technology | Wang Z.J.,PLA University of Science and Technology
Applied Mechanics and Materials | Year: 2014

In this paper, electromagnetic field distribution adjacent to the aperture is analyzed to help deducing the coupling principle of apertures. The aperture is located on an infinite plate to avoid the effect of other structures. Taking advantage of high-resolution standard finite-difference time-domain (FDTD) simulation, it is possible to observe the electromagnetic field distribution adjacent to the aperture. From analyses, it can be seen that the electromagnetic field component is dramatically varied adjacent to the aperture, and conclusions drawn here is helpful to deduce the coupling principle of apertures. © (2014) Trans Tech Publications, Switzerland. Source


Zhang Y.,PLA University of Science and Technology | Kan C.,PLA Zhenjiang Watercraft Academy | Zhang L.,Engineer Academy of PLA
International Conference on Communication Technology Proceedings, ICCT | Year: 2015

In this paper, we investigate the problem of global optimization for distributed carrier aggregation (CA) in LTE with unlicensed spectrum, using a game theoretic solution. To cope with the local influences and the distinct cost of different CA types, we propose a non-cooperation game which is proved as an exact potential game. Furthermore, we propose a concurrent log-linear learning based uncoupled algorithm to converge towards NE of the game. In this algorithm, concurrent learning is introduced to accelerate the convergence speed. It is shown that with the proposed game-Theoretic approach, global optimization is achieved without exchanging information. Simulation results validate the effectiveness of the proposed game-Theoretic CA approach. © 2015 IEEE. Source


Lu F.,PLA University of Science and Technology | Ma Y.,PLA University of Science and Technology | Xiong R.,PLA University of Science and Technology | Xiong R.,Engineer Academy of PLA | And 2 more authors.
International Journal of Applied Electromagnetics and Mechanics | Year: 2015

In this paper, uniaxial anisotropic perfectly matched layer (UPML) absorbing boundary condition (ABC) of dispersive materials is presented for 2-D finite-difference time-domain (FDTD) method with weighted Laguerre polynomials (WLP). Taking advantage of the auxiliary differential equation (ADE) technique, our proposed algorithm avoids not only the complicated formulations but also the convolution integral. Using ADE scheme, the relationship between field components and auxiliary differential variables is derived in Laguerre domain. Substituting auxiliary differential variables into UPML-ABC, the electric field E of order q can be expressed directly by magnetic field H in Laguerre domain. Inserting magnetic field H of order q$ into electric field, and using central difference scheme, the formulations of uniaxial anisotropic dispersive media PML are obtained. One numerical example of wave propagation in 2-D dispersive materials is simulated. Numerical results validate the efficiency of the presented method. © 2015 -IOS Press and the authors. Source


Zhang N.Y.,Engineer Academy of PLA | Li X.Q.,Engineer Academy of PLA | Qu L.Y.,PLA University of Science and Technology
Advanced Materials Research | Year: 2014

Plant camouflage is one of the camouflage methods, which is conducted by using of planting and collecting plant and changing color of plant to conceal targets. It can be used to camouflage relatively big permanent fixed targets in peace time and also to camouflage relatively big permanent fixed targets in peace time and also to camouflage relatively small fixed or moving targets. However, in recent years, with the natural disasters occurring alternately, plant camouflage can be destroyed easily, and it is difficult to rebuild in a short time. To improve the effect of plant camouflage, more fertilizers are required, which may become an environmental hazard, unless adequate technical and socioeconomic impacts are addressed. A multifunctional slow-release nitrogen fertilizer has been developed to improve fertilizer use efficiency and reduce environmental pollution. In this paper, a series of slow-release formulations of nitrogen fertilizer were developed on the basis of natural attapulgite clay, ethylcellulose film, and sodium carboxymethylcellulose/hydroxylethylcellulose hydrogel. The structural of the product were examined. The slow-release profiles of ammonium chloride, ammonium sulfate, and urea as nitrogen fertilizer substrates were determined in soil. © (2014) Trans Tech Publications, Switzerland. Source

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