Tang, Min*;Yan, Feng;Deng, Shuguang;Shen, Lianfeng;Kuang, Sufeng;Xing, Song
2016 8th International Conference on Wireless Communications & Signal Processing (WCSP),2016年:1-5 ISSN：2325-3746
[Yan, Feng; Shen, Lianfeng; Tang, Min; Kuang, Sufeng] Southeast Univ, Natl Mobile Commun Res Lab, Nanjing 210096, Jiangsu, Peoples R China.;[Deng, Shuguang] Hunan City Univ, Coll Commun & Elect Engn, Yiyang 413000, Peoples R China.;[Xing, Song] Calif State Univ Los Angeles, Dept Informat Syst, Los Angeles, CA 90032 USA.
[Tang, Min] Southeast Univ, Natl Mobile Commun Res Lab, Nanjing 210096, Jiangsu, Peoples R China.
8th International Conference on Wireless Communications and Signal Processing (WCSP)
OCT 13-15, 2016
Yangzhou, PEOPLES R CHINA
[Tang, Min;Yan, Feng;Shen, Lianfeng;Kuang, Sufeng] Southeast Univ, Natl Mobile Commun Res Lab, Nanjing 210096, Jiangsu, Peoples R China.^[Deng, Shuguang] Hunan City Univ, Coll Commun & Elect Engn, Yiyang 413000, Peoples R China.^[Xing, Song] Calif State Univ Los Angeles, Dept Informat Syst, Los Angeles, CA 90032 USA.
International Conference on Wireless Communications and Signal Processing
In this paper, two coverage optimization algorithms based on Voronoi diagram are proposed to reduce the energy consumption of software-defined sensor networks (SDSNs). In the first algorithm named Minimax Radius Algorithm (MRA), we try to reduce the sensing radii of nodes as much as possible while preserving the original network coverage. In the second algorithm named Sleeping-based Algorithm (SLA), we try to set as many nodes as possible into sleep mode without generating new coverage holes. Simulation results show that both algorithms can reduce the energy consumption significantly and the energy reduction rate increases with no des' sensing radius and the number of nodes.
Journal of Southeast University (English Edition),2014年(4):411-415 ISSN：1003-7985
[沈连丰; 邓杨保] National Mobile Communications Research Laboratory, Southeast University, Nanjing, China;[张光富; 田野; 熊翠秀; 邓杨保; 邓曙光] College of Communication and Electronic Engineering, Hunan City University, Yiyang, China
National Mobile Communications Research Laboratory, Southeast University, Nanjing, China
When laser pulses propagate in an inhomogeneous nonlinear medium, we theoretically investigate the evolution of laser pulses by analytically solving the (3 + 1)-dimensional generalized nonlinear Schrodinger equation with variable coefficients and optical lattice. A series of chirped-free and chirped analytic solutions, such as soliton solutions are found and intensities evolution of these analytic solutions are studied in detail. In the absence of optical lattice, we find that the intensities evolution of chirped-free and chirped analytic solutions vary regularly when the diffraction coefficient is the same as the dispersion coefficient. When the diffraction coefficient is different from the dispersion coefficient, the intensities evolution of chirped-free analytic solutions are regular variation, but the intensities evolution of chirped analytic solutions are irregular. In the presence of optical lattice, the intensities evolution of chirped analytic solutions vary regularly because the diffraction coefficient and the dispersion coefficient are always identical. (C) 2017 Elsevier GmbH. All rights reserved.
We experimentally study the spatiotemporal evolution of chirped femtosecond laser pulses at a specific spatial position, such as the modulation peak position (MPP), during small-scale self-focusing (SSSF). It is found that the spatial peak intensity at the MPP increases rapidly initially with increment of input power due to the effect of SSSF, however it becomes saturated at the higher power because the finite energy of the beam restraints increasing of the peak intensity at the MPP. The pulse width at the MPP is compressed gradually with rising power owing to the spatiotemporal coupling effect, which will reach the narrowest when the spatial peak intensity at the MPP reaches the maximum. Further, the influence of chirp on the pulse width evolution at the MPP is discussed theoretically. We find that the negative chirp accelerates the pulse width compression because the negative chirp enhances the process of SSSF, but the positive chirp is counterproductive. Our results may provide some helps for propagation and amplification of broadband laser pulses.
Small-scale self-focusing (SF) causes rapid increase in the partial spatial intensity, breaking up the spatial profile of the beam into an intensity increasing zone (IZ) and a non-increasing zone (NIZ). We measure the evolutions of the pulse width at the IZ and NIZ with small-scale SF, and our results show that the pulse width at the IZ becomes narrower with increasing partial spatial intensity. The pulse width at the NIZ is almost unchanged with increasing laser power. We find that our experimental results are in good agreement with an approximate theoretical analysis.
[沈连丰; 邓曙光; 李俊超] National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China;[邓曙光] Department of Physics and Telecommunication Engineering, Hunan City University, Yiyang 413000, China
National Mobile Communications Research Laboratory, Southeast University, China
Journal of Central South University,2013年(6):1572-1581 ISSN：2095-2899
[Tan Guan-zheng; Tan Yue] Cent S Univ, Sch Informat Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Tan Yue; Deng Shu-guang] Hunan City Univ, Sch Commun & Elect Engn, Yiyang 413000, Peoples R China.
[Tan Guan-zheng] Cent S Univ, Sch Informat Sci & Engn, Changsha 410083, Hunan, Peoples R China.
particle swarm optimization;differential evolution;chaotic local search;reliability-redundancy allocation
In order to solve reliability-redundancy allocation problems more effectively, a new hybrid algorithm named CDEPSO is proposed in this work, which combines particle swarm optimization (PSO) with differential evolution (DE) and a new chaotic local search. In the CDEPSO algorithm, DE provides its best solution to PSO if the best solution obtained by DE is better than that by PSO, while the best solution in the PSO is performed by chaotic local search. To investigate the performance of CDEPSO, four typical reliability-redundancy allocation problems were solved and the results indicate that the convergence speed and robustness of CDEPSO is better than those of PSO and CPSO (a hybrid algorithm which only combines PSO with chaotic local search). And, compared with the other six improved meta-heuristics, CDEPSO also exhibits more robust performance. In addition, a new performance was proposed to more fairly compare CDEPSO with the same six improved meta-heuristics, and CDEPSO algorithm is the best in solving these problems.
We study the physical-vapor-deposition of 1D bismuth nanostructures. Bi nanowire elongating along  and/or  direction as well as anisotropic Bi nano-columns are physical-vapor-deposited successfully. The coexistence and competition of surface diffusion and geometric shielding are critical to their formation as well as growth mode transition among them. Since physical-vapor-deposition is a vacuum process, we make use of it to fabricate the ohmic contact to prevent the damage to the bismuth nanostructures brought by the etching to their thick surface oxide layer.
[燕锋; 丁兆明; 沈连丰; 朱亚萍] National Mobile Communications Research Laboratory, Southeast University, Nanjing, 210096, China;[邓曙光] College of Communications and Electronics Engineering, Hunan City University, Yiyang, 413000, China