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Proceedings of the 2017 2nd International Conference on Communication and Information Systems

作者： Ao-Lin Yan Li-Hua Wang Bo Wu Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University Anhui Hefei China

ISBN: (纸本)9781450353489

Considering the photonic crystal structure is critical to the future development of communication, the enthusiasm for the research of photonic crystal is always high. In this paper, the nonlinear finite-difference time-domain method is used to analyze the transmission characteristics of one-dimensional photonic crystal structure. As the center frequency of the optical pulse approaches is closed to the photonic band gap, the group velocity dispersion of the light pulse increases. In addition, soliton waves can be generated in the structure with the introduction of Kerr nonlinear. And soliton waves can make outstanding contributions to the accurate transmission of information.

关键词： Nonlinear finite-difference time-domain (N-FDTD) Kerr nonlinear photonic crystals

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Multi-temporal MOD09A1-based detecting of major growth stages of paddy rice on a provincial scale 37

Multi-temporal MOD09A1-based detecting of major growth stage...

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37th Annual IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2017

作者： Huang, Linsheng Zhang, Shasha Zhao, Jinling Huang, Wenjiang Huang, Jinyang Qi, Xiaobo Anhui Engineering Laboratory Agro-Ecological Big Data Anhui University Hefei230601 China Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei230039 China Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing100094 China

ISBN: (纸本)9781509049516

Growth stage information is a very primary parameter for managing the grain crop. In this study, time series Enhanced Vegetation Index (EVI) data in 2015 were obtained in Anhui Province, China based on 8-day composite MOD09A1 data products, and the extraction method of rice phenology was specifically analyzed at a provincial scale. HANTS (Harmonic Analysis of Time Series) filtering algorithm was firstly used to smooth the time series EVI curves and identify every growth and development period of paddy rice. The results indicate that HANTS has a better performance in removing noise, restoring original information and retain the change information of multi-temporal EVI curves. The primary planting regions were located in the southern Huai-River areas, from early June to late June in 2015. It turned into the transplanting stage in succession from south to north and followed by the heading stage in succession in early August. From early September to late October, it turned into mature stage from south to north in succession. © 2017 IEEE.

关键词： Indexes

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Investigation of broadband terahertz generation from metasurface

arXiv

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arXiv 2018年

作者： Fang, Ming Niu, Kaikun Huang, Zhiaxiang Sha, Wei E.I. Wu, Xianliang Koschny, Thomas Soukoulis, Costas M. Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei230039 China Key Laboratory of Micro-nano Electronic Devices and Smart Systems of Zhejiang Province College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Ames Laboratory U.S. Doe and Department of Physics and Astronomy Iowa State University AmesIA50011 United States Forth Heraklion71110 Greece

The nonlinear metamaterials have been shown to provide nonlinear properties with high nonlinear conversion efficiency and in a myriad of light manipulation. Here we study terahertz generation from nonlinear metasurface consisting of single layer nanoscale split-ring resonator array. The terahertz generation due to optical rectification by the second-order nonlinearity of the split-ring resonator is investigated by a time-domain implementation of the hydrodynamic model for electron dynamics in metal. The results show that the nonlinear metasurface enables us to generate broadband terahertz radiation and free from quasi-phase-matching conditions. The proposed scheme provides a new concept of broadband THz source and designing nonlinear plasmonic metamaterials. Copyright © 2018, The Authors. All rights reserved.

关键词： Ring gages

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An improved Gaussian Mixture Model algorithm for background representation

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Journal of Physics: Conference Series 2019年第1期1325卷

作者： Ping Wang Shaoxiong Dong School of Electrical Engineering and Electronic Information Xihua University Chengdu Sichuan 610039 China Artificial Intelligence Key Laboratory of Sichuan Province Sichuan University of Science and Engineering Zigong Sichuan 643000 China Science Computing Intelligent Information Processing of GuangXi higher education key laboratory Guangxi Teachers Education University Nanning 530023 China

Initializing a background frame for Gaussian Mixture Model requires no moving objects in the background scene. In this paper, in order to obtain an initial frame when there is a moving object in the background scene, filtering algorithm is used for background frame initialization. This paper proposes an improved method for updating Gaussian mixture models. In the initial stage of the GMM, the update rate of the mean and variance is taken as a larger value, so that the model mean and variance update speed becomes faster, and the model learning speed is accelerated; after training for a period of time with a large update rate, let The mean update rate is unchanged, and the variance update rate becomes smaller, so that the background model can be more stable.

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Object Recognition Based on Maximally Stable Extremal Region and Scale-Invariant Feature Transform

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Telkomnika (Telecommunication computing Electronics and Control) 2016年第2期14卷 622-629页

作者： Guo, Hongjun Chen, Lili Laboratory of Intelligent Information Processing Suzhou University Suzhou234000 China The Key Laboratory of Intelligent Computing and Signal Processing of MOE Anhui University Hefei230039 China

For the defect in describing affine and blur invariable of scale-invariant feature transform (SIFT) at large viewpoint variation, a new object recognition method is proposed in this paper, which used maximally stable extremal region (MSER) detecting MSERs and SIFT describing local feature of these regions. First, a new most stability criterion is adopt to improve the detection effect at irregular shaped regions and under blur conditions;then, the local feature descriptors of MSERs is extracted by the SIFT;and finally, the method proposed is comparing then correct rate of SIFT and the proposed through image recognition with standard test images. Experimental results show that the method proposed can still achieve more than 74% recognition correct rate at different viewpoint, which is better than SIFT. © Copyright 2016 Universitas Ahmad Dahlan.

关键词： Object recognition

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A new approach to the Kasami codes of type 2

arXiv

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arXiv 2018年

作者： Shi, Minjia Krotov, Denis S. Solé, Patrick The Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education School of Mathematics Anhui University Anhui230601 China The Sobolev Institute of Mathematics pr. Akademika Koptyuga 4 Novosibirsk630090 Russia The CNRS LAGA University of Paris 8 2 rue de la Liberté Saint-Denis93 526 France

The dual of the Kasami code of length q2 − 1, with q a power of 2, is constructed by concatenating a cyclic MDS code of length q + 1 over Fq with a Simplex code of length q − 1. This yields a new derivation of the weight distribution of the Kasami code, a new description of its coset graph, and a new proof that the Kasami code is completely regular. The automorphism groups of the Kasami code and the related q-ary MDS code are determined. New cyclic completely regular codes over finite fields a power of 2, generalized Kasami codes, are constructed;they have coset graphs isomorphic to that of the Kasami codes. Another wide class of completely regular codes, including additive codes, as well as unrestricted codes, is obtained by combining cosets of the Kasami or generalized Kasami *** Codes 05E30, 94B05 Copyright © 2018, The Authors. All rights reserved.

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An Anti-Eavesdrop Transmission Scheduling Scheme Based on Maximizing Secrecy Outage Probability in Ad Hoc Networks

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China Communications 2016年第1期13卷 176-184页

作者： WANG Yajun LIAO Tongqing WANG Chuanan School of Mathematical and Information Engineering Anhui Science and Technology University Ministry of Educational Key Laboratory of Intelligent Computing and Signal Processing Anhui University

In this paper,we consider a wireless ad hoc network consisting of multiple source nodes transmitting to their respective destinations,where an eavesdropper attempts to intercept their *** propose an optimal transmission scheduling scheme to defend against the eavesdropper,where a source node having the highest secrecy rate is scheduled to access the wireless medium for transmitting to its destination in an opportunistic *** be specific,the secrecy rate between a pair of the source and destination in the presence of an eavesdropper varies temporally due to the wireless fading *** proposed optimal transmission scheduling scheme opportunistically selects a source node with the highest secrecy rate to transmit its data for the sake of maximizing the security of the ad hoc network against eavesdropping *** comparison purposes,we also consider the conventional round-robin scheduling as a benchmark,where multiple source nodes take turns in accessing their shared wireless medium for transmitting to their respective *** derive closed-form secrecy outage probability expressions of both the round-robin scheduling and the proposed optimal scheduling schemes over Rayleigh fading *** results show that the proposed transmission scheduling scheme outperforms the conventional round-robin method in terms of its secrecy outage ***,upon increasing the number of source-destination pairs,the secrecy outage probability of the round-robin scheme keeps unchanged,whereas the secrecy outage performance of the proposed transmission scheduling significantly improves,showing the security benefits of exploiting transmission scheduling for protecting wireless ad hoc networks against eavesdropping.

关键词： transmission scheduling eavesdropping secrecy outage probability secrecy rate rayleigh fading

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MacWilliams identities of linear codes with respect to RT metric over Mn×s (F2[u, v]{uk, v2, uv-Vu})

MacWilliams identities of linear codes with respect to RT me...

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作者： Shi, Minjia Tang, Jie Ge, Maorong Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University No. 3 Feixi Road Hefei Anhui Province230039 China National Mobile Communications Research Laboratory Southeast University Nanjing210096 China School of Mathematical Sciences Anhui University Hefei230601 China

The definitions of the Lee complete ρ weight enumerator and the exact complete ρ weight enumerator over Mn×s (F2[u, v]{uk, v2, uv-vu}) are introduced, and the MacWilliams identities with respect to the RT metric for these two weight enumerators of linear codes over Mn×s (F2[u, v]{uk, v2, uv-vu}) are obtained. Finally, we give two examples to illustrate the results we obtained. Copyright © 2017 The Institute of Electronics, Information and Communication Engineers.

关键词： Codes (symbols)

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Multiple spacecraft formation flying control around Sun-Earth L2 libration point

Multiple spacecraft formation flying control around Sun-Eart...

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Youth Academic Annual Conference of Chinese Association of Automation (YAC)

作者： Yating Yin Teng Li Zhangpeng Lou Key Laboratory of Intelligent Computing & Signal Processing Anhui University Hefei China Department of Automation University of Science and Technology of China

ISBN: (纸本)9781538629024

Multiple spacecraft formation flying is an important concept for future deep-space exploration missions. It requires reliable techniques for the control of formation configuration. This paper addresses the control problem of spacecraft formation flying around the Sun-Earth L 2 libration point utilizing the framework of the circular restricted three-body problem (CR3BP). A leader/follower formation scheme consisting of one leader and three follower spacecraft is considered. The leader spacecraft is assumed to be in a fixed Halo orbit. The position of each follower spacecraft relative to the leader is controlled to be a constant using an active disturbance rejection control (ADRC) method. In this method, the unknown dynamics and external disturbances of the formation flying system are estimated by an extended state observer (ESO), and a nonlinear state error feedback control law is used to compensate for them in real time. Perturbative forces due to solar radiation pressure and the eccentric nature of the Earth's orbit are modeled as external disturbances. Numerical simulations and comparisons with an existing method show that desired formations are obtained with high accuracy using the proposed ADRC method.

关键词： Space vehicles Orbits Earth Mathematical model Dynamics Nonlinear dynamical systems Real-time systems

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Dynamic Smooth Handover Method based on Transition Zones

Dynamic Smooth Handover Method based on Transition Zones

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2017 6th International Conference on Advanced Materials and Computer Science(ICAMCS 2017)

作者： Ren Wang Yi Wang Liangliang Tian Yan Liu Key Laboratory of Intelligent Computing & Signal Processing Ministry of EducationAnhui University School of Electronics and Information Engineering Anhui University

In order to improve coverage and load balancing in cellular networks,CRE（Cell Range Expansion）which is introduced in LTE-Advanced has drawn significant ***,the ping-pong effect resulting from cell handover is still a *** this paper,we propose a new dynamic smooth handover method based on transition zones for the celledge users to deal with the ping-pong *** cells’boundaries extend to transition zones within which the users do not switch serving *** the other hand,the range of the transition zones can be adjusted depending on performance *** results show that our proposed method is near optimum throughput and traffic load performance without the ping-pong effect.

关键词： CRE Transition zone Ping-Pong effect

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