作者机构：
[刘华] School of Electrical Engineering, University of South China, Hengyang;Hunan;421001, China;[韩文兴; 陈智] Nuclear Power Institute of CHINA, Chengdu;610041, China
摘要：
We have numerically investigated the propagation properties of ring Airy beams modeled by a fractional Schrödinger equation (FSE). Beam splitting is exhibited and clarified from the view of group delay. Compared with the case of the condition in free space, the focal intensity is greatly enhanced and presents a trend from increasing to decreasing with the decrement of the Lévy index, while the focal length largely increases; in addition, the parabolic trajectory is distorted with the Bessel pattern gradually disappearing. However, both the focal intensity and its length get decreased due to the absence of the initial phase of ring Airy beams; simultaneously, the size of the focal spot decreases for a larger Lévy index. The changes of focusing properties are clearly clarified. Moreover, without initial phase, the ratio of focal intensity under the Lévy index to the condition in free space is given to show the faster growth of focal intensity when the Lévy index is lower than 1.25; otherwise, the trend gets reversed. The autofocusing properties of ring Airy beams modeled by FSE can find applications in optical trapping and manipulation.
作者机构：
[陈云; 赵立宏] School of Electric Engineering, University of South China, Hengyang;Hunan;421001, China;[于涛; 何丽华; 刘紫静; 谢金森] School of Nuclear Science and Technology, University of South China Hengyang, Hunan;[陈云; 赵立宏] Hunan
通讯机构：
School of Nuclear Science and Technology, University of South China Hengyang, Hunan, China
摘要：
The evolution of the ring Airy Gaussian beams with a modulated vortex in free space is numerically investigated. Compared with the unmodulated vortex, the unique property is that the beam spots first break up, and then gather. The evolution of the beams is influenced by the parameters of the vortex modulation, and the splitting phenomenon gets enhanced with multiple rings becoming light spots if the modulation depth increases. The symmetric branch pattern of the beam spots gets changed when the number of phase folds increases, and the initial modulation phase only impacts the angle of the beam spots. Moreover, a large distribution factor correlates to a hollow Gaussian vortex shape and weakens the splitting and gathering trend. By changing the initial parameters of the vortex modulation and the distribution factor, the peak intensity is greatly affected. In addition, the energy flow and the angular momentum are elucidated with the beam evolution features being confirmed.
期刊：
PROCEEDINGS OF THE 25TH INTERNATIONAL CONFERENCE ON NUCLEAR ENGINEERING, 2017, VOL 2,2017年2
通讯作者：
Li Meng
作者机构：
[Li Meng; Yang Xiao-Hua] CNNC Key Lab High Trusted Comp, Hengyang 421001, Hunan, Peoples R China.;[Li Yu-Yan; Wang Li-Jun] Univ South China, Sch Elect Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Li Meng] C;CNNC Key Lab High Trusted Comp, Hengyang 421001, Hunan, Peoples R China.
会议名称：
25th International Conference on Nuclear Engineering
会议时间：
JUL 02-06, 2017
会议地点：
Shanghai, PEOPLES R CHINA
会议主办单位：
[Li Meng;Yang Xiao-Hua] CNNC Key Lab High Trusted Comp, Hengyang 421001, Hunan, Peoples R China.^[Wang Li-Jun;Li Yu-Yan] Univ South China, Sch Elect Engn, Hengyang 421001, Hunan, Peoples R China.
摘要：
In view of the characteristics of the physical code Nestor the focus is on the correctness of calculation for which the test adequacy criterion has been established. This is based on structural coverage and the input domain. According to such test adequacy criterion, testing strategies have been applied on the entire testing process. They consist of unit static, unit dynamic, integration, system and regression test strategy. Each strategy is composed of test target, test range, technology and method, entry criterion, completion criterion, test focus and priority. After compared with 11 basic benchmarks from nuclear power plants and calculation result of benchmark programs, the ELEMENT program result is correct and credible; the relative error of result is less than three percent. The ELEMENT testing is adequacy. Its test cases covers fuel grid element types, fuel types, non-combustible grid element types, and control rod computational models. Furthermore, it puts forward a research direction in the future.
摘要：
We show that the group-velocity-led optical event horizon (OEH) in optical fibers provides a convenient way to actively control the propagation property of higher-order solitons by a comparatively weak dispersive wave (DW) pulse. It has been found numerically that clean soliton breakup, a process by which a second-order soliton completely splits into a pair of constituent solitons with vastly different power proportions after interacting with the weak DW pulse, will occur while external DWs become polychromatic. The temporal separation between both constituent solitons can be controlled by adjusting the power of the external DW. The more energetic main soliton is advanced/trailed in time depending on the selected frequency of input DW pulse. We have developed an analytic formalism describing the external acting-force (AF) perturbation. These results provide a fundamental explanation and physical scaling of optical pulse evolution in optical fibers and can find applications in improved supercontinuum sources.
期刊：
IEEE Transactions On Electron Devices,2017年64(9):3654-3660 ISSN：0018-9383
通讯作者：
He, Hongyu
作者机构：
[He, Hongyu] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;[He, Hongyu] Peking Univ, Shenzhen Grad Sch, Sch Elect & Comp Engn, Shenzhen 518005, Peoples R China.;[Liu, Yuan; Zheng, Xueren] South China Univ Technol, Sch Microelect, Guangzhou 510640, Guangdong, Peoples R China.;[Yan, Binghui] South China Agr Univ, Coll Elect Engn, Guangzhou 510642, Guangdong, Peoples R China.;[Lin, Xinnan] Peking Univ, Shenzhen Grad Sch, Sch Elect & Comp Engn, Shenzhen Key Lab Adv Electron Device & Integrat, Shenzhen 518005, Peoples R China.
通讯机构：
[He, Hongyu] U;[He, Hongyu] P;Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;Peking Univ, Shenzhen Grad Sch, Sch Elect & Comp Engn, Shenzhen 518005, Peoples R China.
关键词：
Analytical model;drain current;temperature characteristics;thin-film transistor (TFT);trap states
摘要：
Surface-potential-based drain current model is presented for amorphous InGaZnO thin-film transistors considering both exponential deep and tail trap states densities in the energy gap. The trap states densities are determined by the numerical calculation on the basis of the assumption that the trapped carrier concentration is much higher than the free carrier concentration. The analytical drain current model is developed consistent with the numerical calculation, and verified by the experimental data at different temperatures.
摘要：
The aim of multi-focus image fusion is to create a synthetic all-in-focus image from several images each of which is obtained with different focus settings. However, if the resolution of source images is low, the fused images with traditional fusion method would be also in low-quality, which hinders further image analysis even the fused image is all-in-focus. This paper presents a novel joint multi-focus image fusion and super-resolution method via convolutional neural network (CNN). The first level network features of different source images are fused with the guidance of the local clarity calculated from the source images. The final high-resolution fused image is obtained with the reconstruction network filters which act like averaging filters. The experimental results demonstrate that the proposed approach can generate the fused images with better visual quality and acceptable computation efficiency as compared to other state-of-the-art works.
关键词：
Barrier coverage;Internet of Things (IoT);barrier gap;directional sensor networks;line-based deployment
摘要：
The barrier coverage of a wireless sensor network is an important surveillance application of Internet of Things. Barrier coverage guarantees that all intruders traversing the protected region are detected by a chain of connected sensors. However, when the sensors are randomly deployed, barrier gaps may occur due to deployment randomness or insufficient sensors. How to locate the barrier gaps and mend them is an important aspect in the network. In this paper, we study the barrier gap problem in weak barrier coverage and strong barrier coverage that consist of directional sensors, and the sensors are deployed by a line-based deployment strategy. A gap-finding algorithm is proposed to find subbarriers and barrier gaps. Two gap-mending algorithms are devised to mend barrier gaps in the network: One algorithm is a simple rotation algorithm that only rotates two critical sensors in two subbarriers to fix the gap, and the other algorithm is a chain-reaction rotation algorithm that rotates sensors in the subbarrier in a chain-reaction manner to mend the gap. We conduct extensive simulations to evaluate the performance of the proposed algorithms. Simulation results show that the proposed gap-mending algorithms can effectively fix barrier gaps and improve the probability of barrier success construction.
摘要：
In order to segment adhesion ore image well, the adhesion ore image separation method based on concave points matching has been proposed. Firstly, adhesion ore images of conveyor belt were obtained by high-speed digital camera, and those images were preprocessed. Secondly, improved Harris corner detection operator was used to detect the corner points, and match concave point pair was determined by corner detection operator coupled with the circular template. Thirdly, sector searching was carried out in simply connected region to match concave point pair and find out the best match concave point pair by rectangular limiting. Finally, division line was determined between concave point pair, and adhesion ore image was completely segmented. Experimental results show the method has high segmentation accuracy and good segmentation effect.
摘要：
The delay time dependence of photoelectron spectra and state populations of three-level ladder K2 molecule is investigated by pump-probe pulses via time-dependent wave packet approach. The periodical motion of the wave packet with oscillating period 500 fs results in the periodical variation of photoelectron spectra. The photoelectron spectra show Autler-Townes double splitting at zero delay time, and no splitting at positive delay time. The periodical change of state populations with delay time can be ascribed to the coupling effect between the two pulses. It is found that the selectivity of the state populations may be attained by regulating the delay time. The results can provide some important basis for realizing the optical control of molecules experimentally.
作者机构：
[饶益花] School of Mathematics and Physics, University of South China, Hengyang;421001, China;[陈文光; 胡波] School of Electrical Engineering, University of South China, Hengyang;[饶军; 余珮炫; 曹建勇] China Southwestern Institute of Physics, Chengdu;610041, China
通讯机构：
[Chen, W.] S;School of Electrical Engineering, University of South China, Hengyang, China
摘要：
Measuring rail profile in the presence of multiple degrees of freedom vibration is a very challenging task. This paper presents a novel method based on the local affine invariant feature descriptor to calibrate distorted profiles, which are obtained by traditional rail measurement system. It has three major modules: local affine invariant (LAI) feature descriptor, affine transformation estimation and parameters refinement. LAI feature descriptor is based on the affine geometry invariant and generated by calculating the proportions of different areas. Using the proposed LAI descriptor, we implement a three-stage profile calibration including matching, estimation, and refinement based on grouping and fast iterative closest point (FICP) algorithm. The performance of proposed LAI descriptor and calibrating method is tested by performing extensive experiments. The experimental results show that our LAI descriptor is highly descriptive and robust with respect to varying resolution and noise, and the LAI descriptor based calibration is effective and repeatable. (C) 2017 Elsevier Ltd. All rights reserved.
通讯机构：
[Pang, Lihui] U;Univ South China, Sch Elect Engn, Hengyang, Peoples R China.
会议名称：
13th IEEE International Conference on Signal Processing (ICSP)
会议时间：
NOV 06-10, 2016
会议地点：
Chengdu, PEOPLES R CHINA
会议主办单位：
[Deng, Xianrong] MStar Semicond Inc, Hardware Designing Dept, Shenzhen, Peoples R China.^[Pang, Lihui;Wang, Xinlin] Univ South China, Sch Elect Engn, Hengyang, Peoples R China.^[Jiang, Kaili] Univ Elect Sci & Technol China, Sch Elect Engineer, Chengdu, Sichuan, Peoples R China.
会议论文集名称：
International Conference on Signal Processing
关键词：
single-channel;blind signal separation;empirical mode decomposition;FastICA;intrinsic mode function
摘要：
This paper presents a new methodology for single-channel blind signal separation (SCBSS) of time-frequency overlapped signals in electromagnetic surveillance domain. This method combines the complete ensemble empirical mode decomposition (CEEMD) with fast independent component analysis (FastICA). Firstly, the single-channel recording is decomposed into a set of intrinsic mode function (IMF) components by the method CEEMD with adaptive noise, for the residue and the number of shifting iterations of CEEMD are smaller than that of other empirical mode decomposition approach. The IMF components become the basis representing the original data. After selecting the usefull IMF components according to their power spectrum, FastICA is used to separate the source of interest in the original signal. Simulation results obtained in evaluating the proposed methodology's performance confirmed the feasibility and effectiveness of this algorithm.
