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Towards an end-to-end delay analysis of LEO satellite networks for seamless ubiquitous access

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science China(information sciences) 2013年第11期56卷 5-17页

作者： CHEN JianZhou LIU LiXiang HU XiaoHui science and technology on Integrated information System Laboratory Institute of SoftwareChinese Academy of Sciences University of Chinese Academy of sciences

LEO satellite networks,with moderate propagation delay and low terminal power requirement,are considered as a promising solution to providing global seamless access services for ubiquitous computing.In order to satisfy the requirement of accessing computing resource for users,end-to-end delays should be bounded for a continual and reliable connectivity.But given dynamic topology and non-uniform distribution of terrestrial users,end-to-end delays within LEO satellite networks are liable to fluctuate.Hence,to examine the delay constraint,an analytical model based on a tandem queue is established under a hot-spot trafc pattern,which is unfavorable for bounded delays.The departure interval moments of a target flow are calculated and ftted for the next link as input parameters,from which queuing delays under cross flows are iteratively obtained.The analytical results show that this model is able to depict the influence by the trafc pattern with satisfying accuracy,which is valuable for the design of routing schemes in satellite networks.

关键词： LEO satellite networks delay analysis tandem hot-spot trafc

White organic light-emitting diodes based on a combined electromer and monomer emission in doubly-doped polymers

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Chinese Physics B 2012年第8期21卷 580-583页

作者：孟令川娄志东杨盛谊侯延冰滕枫刘小君李云白 Key Laboratory of Luminescence and Optical information Ministry of EducationInstitute of Optoelectronic TechnologyBeijing Jiaotong University Laboratory of Nanophotonics Materials and technology Center for Micro and Nano Technology&School of Materials Science and EngineeringBeijing Institute of Technology

We report on white organic light-emitting diodes （WOLEDs） based on polyvinylcarbazole （PVK） doped with 1,1-bis（（di-4-tolylamino）phenyl）cyclohexane （TAPC） and perylene, and investigate the luminescence mechanism of the devices. The chromaticity of light emission can be tuned by adjusting the concentration of the dopants. White light with the Commission Internationale de L＇Eclairage （CIE） coordinates of （0.33, 0.34） is achieved by mixing the yellow electromer emission of TAPC and the blue monomer emission of perylene from the device ITO/PVK： TAPC： perylene （100：9：1 in wt.）（100 nm）/tris-（8-hydroxyquinoline aluminum （Alq3）（10 nm）/A1. The device exhibits a maximal luminance of 3727 cd/m2 and a current efficiency of 2 cd/A.

关键词： white organic light-emitting diodes electromer emission monomer emission Commis-sion Internationale de L＇Eclairage （CIE）

Directly mapping whispering gallery modes in a microsphere through modal coupling and directional emission

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Chinese Optics Letters 2008年第4期6卷 300-302页

作者：董春华肖云峰杨勇韩正甫郭光灿 Lan Yang Key Laboratory of Quantum information University of Science and Technology of China Hefei 230026 Department of Applied Physics California Institute of Technology Pasadena California 91125 USA

We fabricate slightly deformed fused-silica microspheres in which whispering gallery modes possess remarkably directional escape emission from the microsphere boundary. With efficient free-space excitation and collection, the lateral spatial distribution of whispering gallery modes with different azimuthal mode numbers, m, is directly observed through modal coupling and directional emission. Excellent agreement with theory is obtained.

关键词： Fused silica Microspheres

SDICN: A Software Defined Deployable Framework of information Centric Networking

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China Communications 2016年第3期13卷 53-65页

作者： WANG Xiulei CHEN Ming HU Chao WENG Xi XING Changyou College of Command information System PLA University of Science & Technology

the information-Centric Networking(ICN) paradigm is proved to have the advantages of decreasing data delivery latency, enhancing user mobility, etc. However, current implementations of ICN require changing the infrastructure of Internet, which hinders its deployment and development. Meanwhile, Software Defined Networking(SDN) emerges as a viable solution to facilitate the deployment of new network paradigm without disrupting production traffic by decoupling the control plane from data forwarding plane. In this paper, the essential properties which reflect ICN working principles are summarized, and a framework called SDICN is designed in accordance to the SDN philosophy. The algorithmic frameworks of SDICN which can satisfy the essential properties are designed based on the programmability and virtualization functions of SDN. Based on Open Flow and data center technology, a prototype of SDICN is implemented. By comparing the performance with the CCNx, the SDICN is proved to be feasibility and availability.

关键词：网络部署算法框架信息中心软件定义网络基础设施控制平面理念设计传输延迟

High-Throughput Rice Density Estimation from Transplantation to Tillering Stages Using Deep Networks

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Plant Phenomics 2020年第1期2卷 255-268页

作者： Liang Liu Hao Lu Yanan Li Zhiguo Cao National Key Laboratory of science and technology on Multi-Spectral information Processing School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan430074 HubeiChina The University of Adelaide AdelaideSA 5005Australia School of Computer science and Engineering Wuhan Institute of TechnologyWuhan430205 HubeiChina

Rice density is closely related to yield estimation,growth diagnosis,cultivated area statistics,and management and damage evaluation.Currently,rice density estimation heavily relies on manual sampling and counting,which is inefficient and inaccurate.With the prevalence of digital imagery,computer vision(CV)technology emerges as a promising alternative to automate this task.However,challenges of an in-field environment,such as illumination,scale,and appearance variations,render gaps for deploying CV methods.To fill these gaps towards accurate rice density estimation,we propose a deep learningbased approach called the Scale-Fusion Counting Classification Network(SFC^(2)Net)that integrates several state-of-the-art computer vision ideas.In particular,SFC^(2)Net addresses appearance and illumination changes by employing a multicolumn pretrained network and multilayer feature fusion to enhance feature representation.To ameliorate sample imbalance engendered by scale,SFC^(2)Net follows a recent blockwise classification idea.We validate SFC^(2)Net on a new rice plant counting(RPC)dataset collected from two field sites in China from 2010 to 2013.Experimental results show that SFC^(2)Net achieves highly accurate counting performance on the RPC dataset with a mean absolute error(MAE)of 25.51,a root mean square error(MSE)of 38.06,a relative MAE of 3.82%,and a R^(2) of 0.98,which exhibits a relative improvement of 48.2%w.r.t.MAE over the conventional counting approach CSRNet.Further,SFC^(2)Net provides high-throughput processing capability,with 16.7 frames per second on 1024×1024 images.Our results suggest that manual rice counting can be safely replaced by SFC^(2)Net at early growth stages.Code and models are available online at https://git.io/sfc2net.

关键词： illumination estimation render

Stabilization for multi-group coupled stochastic models by delay feedback control and nonlinear impulsive control

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science China(information sciences) 2018年第7期61卷 119-129页

作者： Chaolong ZHANG Feiqi DENG Yiping LUO Department of Computational science Zhongkai University of Agriculture and Engineering Systems Engineering institute South China University of Technology College of Electrical and information Engineering Hunan Institute of Engineering

Stabilization for multi-group coupled models stochastic by delay feedback control and nonlinear impulsive control are considered in this paper. Using graph theory and Lyapunov method, some sufficient conditions are acquired by some control methods. Those criteria are easier to verify and no need to solve any linear matrix inequalities. These results can be designed more easily in practice. At last, the effectiveness and advantage of the theoretical results are verified by an example.

关键词： stabilization graph theory stochastic impulsive delay

A Novel Structural Measure Separating Non-Coding RNAs from Genomic Backgrounds

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Tsinghua science and technology 2015年第5期20卷 474-483页

作者： Yingfeng Wang Russell L.Malmberg Liming Cai the School of information technology Middle Georgia State University Department of Plant Biology and institute of Bioinformatics University of Georgia Department of Computer science and institute of Bioinformatics University of Georgia

RNA secondary structure has become the most exploitable feature for ab initio detection of non-coding RNA（nc RNA） genes from genome sequences. Previous work has used Minimum Free Energy（MFE） based methods developed to identify nc RNAs by measuring sequence fold stability and certainty. However, these methods yielded variable performances across different nc RNA species. Designing novel reliable structural measures will help to develop effective nc RNA gene finding tools. This paper introduces a new RNA structural measure based on a novel RNA secondary structure ensemble constrained by characteristics of native RNA tertiary structures. The new method makes it possible to achieve a performance leap from the previous structure-based methods. Test results on standard nc RNA datasets（benchmarks） demonstrate that this method can effectively separate most nc RNAs families from genome backgrounds.

关键词： RNA secondary structure RNA tertiary structure Inside algorithm

Noise Characteristics of Optocouplers on Neutron Radiation

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Chinese Physics Letters 2008年第11期25卷 4093-4096页

作者：李应辉陈春霞刘永智蒋城邹泽亚欧熠李祖安 School of Optoelectronic information University of Electronic Science and Technology of China Chengdu 610054 China Electronics technology Group Corporation No 44 Research institute Chongqing 400060

中子剂量放射实验被设计学习 optocoupler 的排水量效果和噪音特征。爆炸噪音在中子放射上在 optocouplers 被介绍，它从实验被显示。与在空间费用区域的排水量缺点增加的增加的中子放射，散布提高并且噪音信号变化增加。都，这些代表... 详细信息

中子剂量放射实验被设计学习 optocoupler 的排水量效果和噪音特征。爆炸噪音在中子放射上在 optocouplers 被介绍，它从实验被显示。与在空间费用区域的排水量缺点增加的增加的中子放射，散布提高并且噪音信号变化增加。都，这些代表噪音时间系列变化，随机的脉搏和增加的噪音复杂性。爆炸噪音变得明显，并且力量光谱密度，典型频率和噪音的时间系列的分数维的尺寸极大地增加。

关键词：噪音中子辐射光电子学物理研究

Optimal precoding for full-duplex base stations under strongly correlated self-interference channels

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Frontiers of information technology & Electronic Engineering 2017年第6期18卷 808-816页

作者： Jun WANG Xiao-jie WEN Chuan HUANG Chao-jin QING College of Electrical and information Engineering Southwest University for NationalitiesChengdu 610041China Beijing institute of Satellite information Engineering Beijing 100086China National Key Laboratory of science and technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China School of Electrical and information Engineering Xihua UniversityChengdu 610039China

We study the optimal precoding for a full-duplex (FD) system, where one FD multi-antenna base station (BS) respectively transmits to and receives from two half-duplex single-antenna mobile users (MUs) on the same time slot and frequency band. At the FD BS, the received signal from the desired MU is severely affected by the extremely strong self-interference (SI) from its transmit antennas to the receive antennas. In the presence of residual SI after imperfect SI cancellation, the downlink transmission rate maximization problem subject to a targeted uplink rate is formulated as a non-convex optimization problem to characterize the achievable rate region for the considered system. Considering the case in which the SI channel is strongly correlated, the above problem is transformed into a convex problem by exploiting the rank-one property of the SI channel, which can be solved efficiently. Finally, numerical results validate the effectiveness of the proposed scheme.

关键词： Linear precoding Full-duplex Achievable rate region Strongly correlated self-interference channel