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RIS-Assisted Communications in Correlated Rayleigh Channels:Comparison of Training Overhead Reduction Schemes

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China Communications 2022年第12期19卷 41-53页

作者： Jue Wang Shuaifeng Lu Jing Wang Zhenyu Jiang Rui Tang ruifeng gao Yingdong Hu Ye Li School of Information Science and Technology Nantong UniversityNantong 226109China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China School of Transportation and Civil Engineering Nantong UniversityNantong 226109China Nantong Research Institute for Advanced Communication Technologies Nantong 226109China

Channel training in reconfigurable intelligent surface(RIS)-assisted communications is usually conducted in an on-off manner,resulting in unaffordable training time overhead when the number of RIS elements is *** this paper,for correlated Rayleigh channels,we compare three typical training overhead reduction schemes,namely RIS element selection(Scheme 1),element grouping(Scheme 2),and statistical CSI-based phase shifts design(Scheme3).For Scheme 1 and Scheme 2,we propose two algorithms to select RIS elements(or form element groups) and determine the optimal number of activated elements(or formed groups),based on the channel correlation information only;for Scheme 3,we consider a semi-definite programming-based approach in the literature,and propose an alternative dominant eigenvector-based method for determining the RIS phase shifts *** extensive simulations,we compare the achievable ergodic rates of these schemes versus the signal-to-noise ratio,the channel correlation level,and the element number-to-coherent time ratio,respectively,and discuss possible switching of the three schemes over these system *** last,operation regions of the considered training overhead reduction schemes are shown in the plane characterized by the system parameters,which provides useful guidelines for practical scheme determination.

关键词： reconfigurable intelligent surface correlated Rayleigh channel training overhead ergodic achievable rate

Structure,variation and assembly processes of bacterial communities in different root-associated niches of tomato under periodic drought and nitrogen addition

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Pedosphere 2024年第5期34卷 892-904页

作者： Dan HE ruifeng gao Honghong DONG Xiaodi LIU Lijuan REN Qinglong WU Qing YAO Honghui ZHU Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Agricultural Microbiomics and Precision Application(MARA) State Key Laboratory of Applied Microbiology Southern ChinaInstitute of MicrobiologyGuangdong Academy of SciencesGuangzhou 510070China College of Plant Protection South China Agricultural UniversityGuangzhou 510642China Department of Ecology Institute of HydrobiologyJinan UniversityGuangzhou 510632China College of Horticulture South China Agricultural UniversityGuangzhou 510642China

Root-associated bacteria play a vital role in the growth and adaptation of host plants to drought *** bacteria can be classified as rhizoplane and rhizosphere bacteria based on their distance from the root *** plants are often exposed to periodic drought and nitrogen(N)addition throughout their life cycle,but the impacts of these factors on the plant and root-associated bacteria are not well *** gain insight into this relationship,we conducted an experiment to monitor the effects of periodic drought and N addition on rhizoplane and rhizosphere bacteria of tomato *** and N addition had interactive effects on plant and soil properties,which varied with the timing of *** were clear divergences in community traits such as alpha diversity,beta diversity,and network topological features between the two types of *** rhizoplane bacteria showed lower alpha diversity but higher beta diversity and were more sensitive to drought and N addition than the rhizosphere *** addition could downsize the effects of drought on rhizoplane bacterial community *** higher proximity to the root might induce a community to develop more cooperation between different members to cope with plant metabolites,as revealed by the more connected and modularized community network of the rhizoplane *** at the seedling stage had great legacy effects on plant and soil *** may enhance selection,cause the dominance of deterministic processes in the assembly of rhizoplane bacteria,and reduce bacterial community network *** conclusion,N addition could interact with drought in affecting tomato plants and their root-associated bacteria,depending on the timing of drought and the fineness of root *** higher sensitivity of rhizoplane bacteria to drought and N addition calls for more research due to their higher proximity and importance to plants in future environmental changes.

关键词： alpha diversity beta diversity community composition co-occurrence network drought stress node-level network feature rhizoplane bacteria rhizospherebacteria

Physical Layer Security for UAV Communications:A Comprehensive Survey

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China Communications 2022年第9期19卷 77-115页

作者： Jue Wang Xuanxuan Wang ruifeng gao Chengleyang Lei Wei Feng Ning Ge Shi Jin Tony Q.S.Quek School of Information Science and Technology Nantong UniversityNantong 226109China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China China Academy of Electronics and Information Technology Beijing 100041China School of Transportation and Civil Engineering Nantong UniversityNantong 226109China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Information Systems Technology and Design Pillar Singapore University of Technology and DesignSingapore 487372Singapore Nantong Research Institute for Advanced Communication Technologies Nantong 226109China

Due to its high mobility and flexible deployment,unmanned aerial vehicle(UAV)is drawing unprecedented interest in both military and civil applications to enable agile and ubiquitous *** operating in an open environment,UAV communications benefit from dominant line-of-sight links;however,this on the other hand renders the communications more vulnerable to malicious ***,physical layer security(PLS)has been introduced to UAV systems as an important complement to the conventional cryptography-based *** this paper,a comprehensive survey on the current achievements of UAV-PLS is *** first introduce the basic concepts including typical static/-mobile UAV deployment scenarios,the unique air-toground channel and aerial nodes distribution models,as well as various roles that a UAV may act when PLS is ***,we start by reviewing the secrecy performance analysis and enhancing techniques for statically deployed UAV systems,and extend the discussion to the more general scenario where the UAVs’mobility is further *** both cases,respectively,we summarize the commonly adopted methodologies,then describe important works in the litera ture in ***,potential research directions and challenges are discussed to provide an outlook for future works in the area of UAV-PLS.

关键词： physical layer security UAV communications static/mobile UAV deployment air-to-ground channel trajectory optimization

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关于太行路高填方路基回填方案的探讨

山西建筑 2015年第4期41卷 136-137页

作者：高瑞锋太原市市政工程设计研究院山西太原030002

结合太原市太行路所处的地理位置,对该道路一般高填方路基段及特殊高填方路基段采用的处理方式进行了研究,阐述了路基施工中的注意事项,包括沟底清理、材料选择、防护设计等,达到了预期的处理效果。

关键词：湿陷性黄土高填方路基边坡管线设计

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煤矿通风机远程故障监测系统设计应用

机械管理开发 2019年第7期34卷 250-251页

作者：高瑞凤大同煤矿集团北辛窑煤业有限公司

为了提高矿用通风机运行效率,降低风机故障率,实现风机远程故障监测监控,大同煤矿集团北辛窑煤业有限公司通风区通过技术研究,设计了一套煤矿通风机远程故障监测系统,并在实际中进行应用,取得了显著成效。

关键词：矿用通风机远程监控故障系统设计

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基于微分对策的水下主动防御拦截导引方法

西北工业大学学报 2016年第5期34卷 851-856页

作者：程瑞锋刘卫东高立娥张建军西北工业大学航海学院陕西西安710072 西北工业大学水下信息与控制重点实验室陕西西安710072

针对来袭水下目标机动方式的无法预知的问题,为实现精确拦截,以目标捕获条件为约束,设计了一种用于水下机动目标拦截的微分对策导引律。以微分博弈理论为基础,构造用于双边最优控制的二次型性能指标,利用伴随原理求解终端问题的方法导... 详细信息

针对来袭水下目标机动方式的无法预知的问题,为实现精确拦截,以目标捕获条件为约束,设计了一种用于水下机动目标拦截的微分对策导引律。以微分博弈理论为基础,构造用于双边最优控制的二次型性能指标,利用伴随原理求解终端问题的方法导出具有状态反馈形式"零效脱靶量",并以其为性能指标设计用于航向角控制的微分对策制导律。通过对机动目标的跟踪拦截表明:该制导律对目标机动方式具有较强的鲁棒性,与最优导引相比,对机动目标的拦截精度高,可满足水下拦截作战技术需求。

关键词：微分对策制导律拦截脱靶量

面向XL-MIMO可视区域识别的非均匀空间采样

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中兴通讯技术 2024年第3期30卷 52-59页

作者：厉凯高锐锋王珏南通大学中国南通226019

超大规模多输入多输出(XL-MIMO)是面向未来6G超级无线宽带和超大规模连接的关键技术,其空间非平稳特性导致局部天线阵列区域可能仅会被部分用户“看到”,称为用户可视区域(VR)。利用VR可实现XL-MIMO低复杂度传输设计,如何识别用户VR是... 详细信息

超大规模多输入多输出(XL-MIMO)是面向未来6G超级无线宽带和超大规模连接的关键技术,其空间非平稳特性导致局部天线阵列区域可能仅会被部分用户“看到”,称为用户可视区域(VR)。利用VR可实现XL-MIMO低复杂度传输设计,如何识别用户VR是其必要前提。由于用户VR与其空间位置存在天然联系,可通过选择少量用户估计并反馈其所在位置处的VR,然后结合用户位置外推出其余用户VR。该过程可解释为“VR地图”的空间采样与重建,外推效果与采样点位置选择关系密切。为提高采样效率,基于探测与细化相结合的设计理念,提出了一种有限样本下的非均匀空间采样方案,并分析探测细化调控因子的设计方法。仿真结果表明,所提方案相较于传统随机采样具有更高的效率,可显著提升小样本下的VR识别准确性。

关键词：超大规模多输入多输出空间采样可视区域识别探测细化

不同种植模式对玉米产量及土壤耕层水分含量和温度的影响

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内蒙古农业科技 2015年第4期43卷 36-37页

作者：高瑞峰凉城县农业技术推广中心内蒙古凉城013750

为了研究全膜覆盖对玉米产量及土壤耕层水分含量和温度的影响,在凉城县主栽作物玉米上进行了全膜覆盖、半膜覆盖、不覆膜三种种植模式的对比试验。试验表明全膜覆盖比半膜覆盖,全膜覆盖比不覆膜土壤耕层水分含量和温度均明显增加。

关键词：全膜覆盖半膜覆盖玉米产量土壤水分温度

超大规模MIMO阵列可视区域空间分布数据集

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电子与信息学报 2024年第8期46卷 3063-3072页

作者：高锐锋苗艳春陈颖王珏张军韩瑜金石南通大学交通学院南通226019 南通大学信息科学技术学院南通226019 南京邮电大学通信与信息工程学院南京210042 东南大学移动通信国家重点实验室南京210096

可视区域(VR)信息可用于降低超大规模多输入多输出(XL-MIMO)系统传输设计复杂度,但现有理论分析与传输设计多基于简化的VR统计分布模型。为评估分析XL-MIMO在实际物理传播场景中的性能,该文公开了XL-MIMO阵列VR空间分布数据集,其由环境... 详细信息

可视区域(VR)信息可用于降低超大规模多输入多输出(XL-MIMO)系统传输设计复杂度,但现有理论分析与传输设计多基于简化的VR统计分布模型。为评估分析XL-MIMO在实际物理传播场景中的性能,该文公开了XL-MIMO阵列VR空间分布数据集,其由环境参数设置、射线追踪仿真、天线场强数据预处理和VR判定准则等步骤构建。该数据集针对典型城区无线传播场景,建立了用户位置采样与场强数据、VR数据之间的关联,总数据条目数量达上亿级。进一步对其中VR形态、VR分布进行了可视化展示与分析,并以基于VR的XL-MIMO用户接入协议为例,利用该数据集对其在真实传播场景中的性能进行了仿真,为该数据集的应用提供了典型样例。

关键词：超大规模MIMO 可视区域射线追踪能量集中度子阵列