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China Communications 2018年第1期15卷 45-51页

作者： Tao liu hailin.Zhang Jiaoying Wang Huihua Fu Ping Wang Jing Li State Key Laboratory of Integrated Service Networks School of Telecommunications Engineering Xidian University Xi'an 710071 China Xi'an Institute of Applied Optics Xi'an 71007 l China

In this work, the performance of free-space optical(FSO) communication system based on maximal ratio combining using binary phase shift keying subcarrier intensity modulation over Gamma-Gamma fading channels has been studied systematically. Under identically or non-identically distributed branches, the analytical expressions for the bit error rate function of signal-to-noise are derived by expressing the modified Bessel function of second kind with Meijer G-function for dualand triple-branch systems, respectively. In terms of H-fox function, the new expressions have more general forms and are more efficient for computation. It is found that the dual-and triple-branch systems significantly outperform the direct link system under weak, moderate and strong turbulence conditions. Monte Carlo simulation is also provided to confirm the accuracy of the proposed model.

关键词： bit error rate dual-and triple-branch free-space optical systems Gamma-Gamma fading maximal ratio combining(MRC)

A MAC PROTOCOL TO SUPPORT HYBRID ANTENNAS IN A WIRELESS LAN

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Journal of Electronics(China) 2007年第3期24卷 309-315页

作者： Zhao Liqiang Zhang hailin.liu Yi State Key Laboratory of Integrated Services Networks Xidian University Xi＇an 710071 China

Hybrid Distributed Coordination Function (HDCF),a modified medium access control pro-tocol of IEEE 802.11 standard,is proposed in this paper to support both smart adaptive array anten-nas and normal omni-directional antennas simultaneously in one wireless LAN. Omni-directional an-tennas follow the standard Distributed Coordination Function (DCF) and smart antennas follow the Directional DCF (DDCF). The proposed DDCF is based on Hybrid Virtual Carrier Sense (HVCS) mechanism,which includes Omni-directional Request-To-Send/Clear-To-Send (ORTS/OCTS) hand-shake mechanism and directional data transmission. HDCF is compatible with DCF. When a node transmits in a directional beam,the other nodes can multiplex the physical channel. Hence,HDCF supports Space Division Multiple Access (SDMA). Simulation results show that HDCF can support hybrid antennas effectively and provide much higher network throughput and lower delay and jitter than DCF does.

关键词： Wireless LAN Smart adaptive array antennas Medium Access Control (MAC) Space Division Multiple Access (SDMA)

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盆栽牡丹生长和生理特性对现蕾期氮肥的响应

山东农业科学 2024年第3期56卷 99-105页

作者：何晗颖赵俊福刘淑杰朱晓琳马海林刘方春司东霞聊城大学农学与农业工程学院山东聊城252059 山东省林业科学研究院资源与环境研究所山东济南250014

为明确牡丹现蕾期氮肥的施肥效应,确定适宜的氮肥用量,通过盆栽培养试验,设置5个氮素水平(0、0.75、1.50、2.25、3.00 g/株),研究现蕾期氮肥不同用量对牡丹生长和生理特性的影响。结果表明,牡丹现蕾期施用氮肥显著影响植株生长、氮素吸... 详细信息

为明确牡丹现蕾期氮肥的施肥效应,确定适宜的氮肥用量,通过盆栽培养试验,设置5个氮素水平(0、0.75、1.50、2.25、3.00 g/株),研究现蕾期氮肥不同用量对牡丹生长和生理特性的影响。结果表明,牡丹现蕾期施用氮肥显著影响植株生长、氮素吸收和光合特性,对功能叶片叶绿素及其组分含量和比例的影响未达显著水平。随氮肥用量的增加,牡丹株高、茎粗、地上部干物质累积量呈先上升后下降的变化趋势;与不施氮相比,低氮(0.75 g/株)处理植株地下部干物质累积量和根长增加,根冠比提高;0.75~1.50 g/株的氮素用量可明显增大花径,延长花期2~3 d,并提前始花期1~2 d;氮素用量2.25 g/株植株净光合速率最大,同时可显著增加地上部氮浓度和氮吸收量,显著提高氮素在地上部的分配比例。采用隶属函数法对牡丹生长状况进行综合评价,得出协同地上部营养生长和生殖生长的最佳氮素用量为1.56 g/株。综上,牡丹现蕾期适量施用氮肥可提高叶片光合效率,促进并协调地上部生长,可作为牡丹管理策略应用于生产实践。

关键词：氮素牡丹现蕾期生长养分吸收光合特性

Waypoints Trajectory Tracking Control for Nonholonomic Unmanned Surface Vehicle under Environment Disturbance

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Waypoints Trajectory Tracking Control for Nonholonomic Unman...

Visualizing fast growth of large single-crystalline graphene by tunable isotopic carbon source

第32届中国控制与决策会议

作者： Yuan Jian liu hailin.Zhang Wenxia Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences) National Engineering and Technological Research Center of Marine Monitoring Equipment Shandong Provincial Key Laboratory of Ocean Environment Monitoring Technology Department of Mechanical and Electrical Engineering Qindao College

ISBN: (数字)9781728158556

ISBN: (纸本)9781728158563

The waypoints trajectory-tracking problem for Unmanned Surface Vehicle with environment disturbance is *** upper-triangle and diagonal matrix decomposition method of Unscented Kalman Filter（UD-UKF） for the environment noise is proposed.A nonlinear error system is derived based on the nonholonomic constraints equations and UD-UKF based finite-time tracking control algorithm for the nonlinear error system is *** we design a finite-time tracking control law to make the initial angle error states of the error system to drive towards a known sliding boundary layer in *** the estimated states using UD-UKF are used to construct a feedback control law in order to achieve finite-time stabilization for heading angle error states;meanwhile the estimated states of the position error for the reduced-order system are adopted to design a state feedback control law in order to achieve the finite time stabilization for position error ***,the effectiveness of control strategies is verified by numerical simulations and comparison results.

关键词： Nonholonomic Unmanned Surface vehicle Waypoints Trajectory-tracking Upper Triangular and Diagonal Matrix Decomposition Unscented Kalman Filter

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Nano Research 2017年第2期10卷 355-363页

作者： Luzhao Sun1 Li Lin Jincan Zhang Huan Wang hailin.Peng Zhongfan liu Center for Nanochemistry Beijing Science and Engineering Center for Nanocarbons Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China

The fast growth of large single-crystalline graphene by chemical vapor deposition on Cu foil remains a challenge for industrial-scale applications. To achieve the fast growth of large single-crystalline graphene, understanding the detailed dynamics governing the entire growth process--including nucleation, growth, and coalescence is important; however, these remain unexplored. In this study, by using a pulsed carbon isotope labeling technique in conjunction with micro-Raman spectroscopy identification, we visualized the growth dynamics, such as nucleation, growth, and coalescence, during the fast growth of large single- crystalline graphene domains. By tuning the supply of the carbon source, a growth rate of 320 μm/min and the growth of centimeter-sized graphene single crystals were achieved on Cu foil.

关键词： large single-crystalline graphene fast growth isotope labelling carbon source

Characterization of tree shrew telomeres and telomerase

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Journal of Genetics and Genomics 2021年第7期48卷 631-639页

作者： Jian Sun Wenjing liu Yongbo Guo hailin.Zhang Dewei Jiang Ying Luo Rong liu Ceshi Chen Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences&Yunnan Province National Resource Center for Non-Human PrimatesKunming Primate Research CenterNational Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyKunmingYunnan 650201China Kunming College of Life Sciences University of Chinese Academy SciencesKunmingYunnan 650204China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Laboratory of Molecular Genetics of Aging&Tumor Medical FacultyKunming University of Science and TechnologyKunmingYunnan 650500China

The use of tree shrews as experimental animals for biomedical research is a new *** recent studies suggest that tree shrews are suitable for studying cancers,including breast cancer,glioblastoma,lung cancer,and hepatocellular ***,the telomeres and the telomerase of tree shrews have not been studied to ***,we characterize telomeres and telomerase in tree *** telomere length of tree shrews is approximately 23 kb,which is longer than that of primates and shorter than that of mice,and it is extended in breast tumor tissues according to Southern blot and flow-fluorescence in situ hybridization(FISH)*** shrew spleen,bone marrow,testis,ovary,and uterus show high telomerase activities,which are increased in breast tumor tissues by telomeric repeat amplification protocol *** telomere length becomes shorter,and telomerase activity decreases with *** tree shrew TERT and TERC are more highly similar to primates than to *** findings lay a solid foundation for using tree shrews to study aging and cancers.

关键词： Tree shrews Telomere TERT TERC Breast cancer

胸腹联合腔镜下食管癌根治术后肺部并发症的危险因素分析及预测模型建立

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现代肿瘤医学 2024年第20期32卷 3886-3890页

作者：杨唯奕刘冉刘海林张志捷苏珍南京医科大学附属淮安第一医院麻醉科江苏淮安223300 株洲市中心医院麻醉科湖南株洲412000

目的:筛选胸腹联合腔镜下食管癌根治术术后肺部并发症(postoperative pulmonary complications,PPCs)发生的危险因素,建立PPCs列线图预测模型,为该类患者PPCs的早期识别和防治提供临床指导。方法:本研究回顾性收集2022年03月至2022年08... 详细信息

目的:筛选胸腹联合腔镜下食管癌根治术术后肺部并发症(postoperative pulmonary complications,PPCs)发生的危险因素,建立PPCs列线图预测模型,为该类患者PPCs的早期识别和防治提供临床指导。方法:本研究回顾性收集2022年03月至2022年08月在南京医科大学附属淮安第一医院行胸腹联合腔镜下食管癌根治术患者的临床资料。根据术后7天内是否发生PPCs,将患者分为PPCs组与非PPCs组。运用SPSS 26.0软件行logistic单因素和多因素回归分析,筛选出PPCs的危险因素。运用R语言建立Nomogram预测模型;并绘制受试者工作特征(ROC)曲线、校准曲线以及临床决策(DCA)曲线分别评价模型的区分度、一致性和临床实用性。结果:本研究共纳入165例患者,发生PPCs 79例。逻辑回归分析显示:男性、肺年龄、术前PEF百分比、术前WBC、术后24 h血糖变异系数是胸腹联合腔镜下食管癌根治术发生PPCs的独立危险因素(P<0.05)。根据这些危险因素构建Nomogram列线图预测模型,ROC曲线下面积0.821,特异性73.3%,敏感性79.7%,校准曲线一致性良好,DCA决策曲线净收益良好。结论:男性、肺年龄、术前PEF百分比、术前WBC、术后24 h血糖变异系数是胸腹联合腔镜下食管癌根治术PPCs发生的独立危险因素。建立的Nomogram列线图模型具有较高的PPCs预测效能,能帮助早期识别PPCs高风险人群。

关键词：胸腹联合腔镜下食管癌根治术肺部并发症危险因素预测模型

The crowded window of object recognition revealed by cortical population codes

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Science China(Life Sciences) 2020年第2期63卷 317-318页

作者： hailin.Ai Nihong Chen Department of Psychology School of Social SciencesTsinghua UniversityBeijingChina IDG/McGovern Institute for Brain Research at Tsinghua University BeijingChina

When a target is surrounded by nearby flankers,it becomes difficult to identify or discriminate its *** phenomenon is known as visual crowding(Pelli and Tillman,2008).It is ubiquitous in peripheral vision and occurs in everyday activities such as reading and visual *** a major bottleneck in conscious perception and object recognition,crowding has been explained by a lack of sufficient resolution in the visual system(He et al.,1996;liu et al.,2009).Due to this limit,the target-flanker distance needs to exceed a critical *** other words,target identification would not be affected unless the distractors are placed outside the“crowded window”,termed as the crowding zone(Toet and Levi,1992).

关键词： everyday outside spacing

Simulation of the screening process on a circularly vibrating screen using 3D-DEM

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Mining Science and Technology 2011年第5期21卷 677-680页

作者： Zhao Lala Zhao Yuemin liu Chusheng Li Jun Dong hailin School of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou 221116 China Key Laboratory of Coal Processing and High Efficient Cleaning ＆ Utilization of Ministry of Education Xuzhou 221008 China School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou 221116 China

A numerical study of the motion particulates follow along a circularly vibrating screen deck was done using the three dimensional Discrete Element Method (DEM). The motion of the particles was analyzed. The effects of vibration amplitude, throwing index, and screen deck inclination angle on the screening process are discussed. The results show that the average velocity of the particles increases along the lon- gitudinal direction of the deck. The screening efficiency is highest when the vibration amplitude, throw- ing index, and screen deck inclination angle are 3-3.5 mm, 2.7 and 15°, respectively. This work is helpful for developing a deep understanding of particle motion and for optimizing screen separator designs.

关键词： Particulate materialsDiscrete Element MethodCircular vibrating screeningNumerical simulation

智能化履带高效移置带式输送机总体布局方案研究

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矿山机械 2024年第7期52卷 69-72页

作者：刘增杰周海霖盛伟青杨洋宁夏天地西北煤机有限公司宁夏石嘴山753000

笔者围绕宁夏回族自治区 2021 年重点研发项目“智能化履带高效移置带式输送机研究”的研发内容、相关问题、技术指标进行调研、分析计算,总结出智能化履带高效移置带式输送机总体布局方案。1 履带高效移置带式输送机组成履带高效移置... 详细信息

笔者围绕宁夏回族自治区 2021 年重点研发项目“智能化履带高效移置带式输送机研究”的研发内容、相关问题、技术指标进行调研、分析计算,总结出智能化履带高效移置带式输送机总体布局方案。1 履带高效移置带式输送机组成履带高效移置带式输送机主要由桁架式机头站、桁架式过渡机身、若干桁架式单元机身和桁架式机尾站、受料装置、控制系统(智能化控制多履带协同自移系统和带式输送机控制系统)、输送带组成,如图1所示。

关键词：带式输送机自移系统桁架式移置智能化控制履带控制系统输送带