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Joint Doppler Shift and Channel Estimation for UAV mmWave System with Massive ULA

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China Communications 2022年第4期19卷 67-82页

作者： Yanan Li Yue Zhu Tiankui Zhang dian fan The China Academy of Information and Communications Technology Beijing 100191China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing key engineering laboratory of testing and validation for smart terminal and hardware

A joint Doppler shift and channel estimation method for the millimeter-wave communication system of an unmanned aerial vehicle(UAV) equipped with a large-scale uniform linear antenna(ULA) array has been proposed. Since Doppler shift induces intercarrier interference, the parameters of the channel paths have been decomposed into the Doppler shift and the channel information. In order to obtain the Doppler shift, a new estimation algorithm based on a combination of discrete Fourier transform and phase rotation has been proposed, which can determine the appropriate number of antennas. In addition to estimating the channel information, a low-complexity joint Doppler shift and channel estimation method has been designed that can quickly obtain accurate estimates. Furthermore, the achievable sum rate, the theoretical bounds of the mean squared errors, and the Cram?er-Rao lower bounds of the estimation method have been derived. The analysis and simulation results prove that the performance of the proposed approach is close to the theoretical inference.

关键词： ULA Doppler shift estimation channel estimation achievable sum rate

Genetic dissection and validation of a major QTL for grain weight on chromosome 3B in bread wheat(Triticum aestivum L.)

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Journal of Integrative Agriculture 2024年第1期23卷 77-92页

作者： Simin Liao Zhibin Xu Xiaoli fan Qiang Zhou Xiaofeng Liu Cheng Jiang Liangen Chen dian Lin Bo Feng Tao Wang Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China The Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100101China

Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six environments.Seven major QTLs,QGl.cib-2D,QGw.cib-2D,QGw.cib-3B,QGw.cib-4B.1,QGlw.cib-2D.1,QTgw.cib-2D.1 and QTgw.cib-3B.1,were consistently identified in at least four environments and the best linear unbiased estimation(BLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic variance.Significant interactions were detected between the two major TGW QTLs and three major GW loci.In addition,QTgw.cib-3B.1 and QGw.cib-3B were co-located,and the improved TGW at this locus was contributed by GW.Unlike other loci,QTgw.cib-3B.1/QGw.cib-3B had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific PCR(KASP)markers,and a comparison analysis indicated that QTgw.cib-3B.1/QGw.cib-3B is likely a novel locus.Six haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and cultivars.According to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of QTgw.cib-3B.1/QGw.cib-3B was predicted.Collectively,the major QTLs and KASP markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement.

关键词： thousand-grain weight QTL mapping haplotype analysis candidate gene

DOA and Subarray-Interval Estimation for Arbitrarily Distributed UAV Swarm System

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China Communications 2023年第4期20卷 102-117页

作者： dian fan Yue Zhu Jia You Zhe Wang Nan Zhong The China Academy of Information and Communications Technology Beijing 100191China The China Academy of Railway Sciences Corporation Limited Beijing 100081China

In this paper,DOA and subarray-interval estimation are considered and applied to arbitrarily distributed unmanned aerial vehicle(UAV)swarm system,in which multiple small UAVs containing uniform linear array(ULA)are divided by unknown intervals because of dynamic moving.Three parameters are taken to indicate the steering vector,namely,the direction of arrivals(DOAs)of target users,the intervals of UAVs,and the orientation angles of UAVs.The orientation angles are first estimated with an auxiliary user and the DOAs are obtained through a search free rooting method,despite the intervals among the UAVs.Afterwards,the intervals among UAVs can also be calculated via exhaustive when the number of target users are no less than three.We further develop a low-complex method to reduce the computational complexity during subarray-interval estimation.The deterministic Cramér-Rao bound(CRB)of the DOA,orientation angle and subarray-interval can be inferred in a closed form.Eventually,numerical instances are cited to verify the research results.

关键词： distributed subarray DOA orientation angle subarray-interval CRB

Understanding endometriosis from an immunomicroenvironmental perspective

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Chinese Medical Journal 2023年第16期136卷 1897-1909页

作者： dian fan Xu Wang Zhixian Shi Yuting Jiang Bohao Zheng Lian Xu Shengtao Zhou Department of Obstetrics and Gynecology Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE and State Key Laboratory of BiotherapyWest China Second HospitalSichuan University and Collaborative Innovation CenterChengduSichuan 610041China Wuxi School of Medicine Jiangnan UniversityWuxiJiangsu 214122China Department of Pathology West China Second HospitalSichuan UniversityChengduSichuan 610041China 不详

Endometriosis,a heterogeneous,inflammatory,and estrogen-dependent gynecological disease defined by the presence and growth of endometrial tissues outside the lining of the uterus,affects approximately 5-10%of reproductive-age women,causing chronic pelvic pain and reduced fertility.Although the etiology of endometriosis is still elusive,emerging evidence supports the idea that immune dysregulation can promote the survival and growth of retrograde endometrial debris.Peritoneal macrophages and natural killer(NK)cells exhibit deficient cytotoxicity in the endometriotic microenvironment,leading to inefficient eradication of refluxed endometrial fragments.In addition,the imbalance of T-cell subtypes results in aberrant cytokine production and chronic inflammation,which contribute to endometriosis development.Although it remains uncertain whether immune dysregulation represents an initial cause or merely a secondary enhancer of endometriosis,therapies targeting altered immune pathways exhibit satisfactory effects in preventing disease onset and progression.Here,we summarize the phenotypic and functional alterations of immune cells in the endometriotic microenvironment,focusing on their interactions with microbiota and endocrine and nervous systems,and how these interactions contribute to the etiology and symptomology of endometriosis.

关键词： Endometriosis Immune cells Microenvironment Inflammation

基于Qt的遥操作GIS维护机器人监控系统设计与实现

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计算机应用与软件 2024年第1期41卷 1-6,81页

作者：范智霖佃松宜四川大学电气工程学院四川成都610065

在电力系统中,为了更好、更方便地遥控操作机器人清理气体绝缘开关设备(Gas Insulated Switchgear,GIS)腔体内的螺栓、螺母等异物,研发GIS维护机器人监控系统。采用Qt平台开发,结合FFMPEG和OpenCV采集RTMP网络视频流并进行图像处理,实... 详细信息

在电力系统中,为了更好、更方便地遥控操作机器人清理气体绝缘开关设备(Gas Insulated Switchgear,GIS)腔体内的螺栓、螺母等异物,研发GIS维护机器人监控系统。采用Qt平台开发,结合FFMPEG和OpenCV采集RTMP网络视频流并进行图像处理,实现对腔体内异物的检测识别与精准定位;以SLAM点云进行环境感知,还原出机器人在腔体内的实际场景。测试结果表明,在无线环境下,该系统可高效实现与机器人的数据交互和有效地实时监控,较好地完成GIS腔体内遗留物的识别与清理。

关键词： Qt 遥操作机器人 OpenCV图像处理 FFMPEG解码环境感知

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数字技术驱动社区体育治理创新的价值与路径

体育文化导刊 2024年第1期 22-28,55页

作者：张殿祥樊炳有苏州大学体育学院江苏苏州215021

运用文献资料、逻辑分析等方法,审视我国社区体育治理成效与困境,并探究数字技术驱动社区体育治理创新的价值与路径。价值:从事后响应转向主动前瞻,从条块分割转向协同联动,从一元主导转向多元共治,从粗放普适转向精准高效。路径:培养... 详细信息

运用文献资料、逻辑分析等方法,审视我国社区体育治理成效与困境,并探究数字技术驱动社区体育治理创新的价值与路径。价值:从事后响应转向主动前瞻,从条块分割转向协同联动,从一元主导转向多元共治,从粗放普适转向精准高效。路径:培养技术应用能力与完善数据决策机制,推动实现主动高效服务;建立健全跨部门协同与跨层级联动平台,推动实现政府组织变革;创新参与机制与搭建协商平台,推动实现多元主体共治;消解技术张力与化解技术风险,推动实现治理手段精准高效。

关键词：体育管理社区体育治理数字技术

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低对称性能谷光子晶体中的拓扑光传输

物理学报 2024年第10期73卷 194-202页

作者：陈鸿翔刘墨点范智斌陈晓东中山大学物理学院广州510275

能谷光子晶体是研究拓扑光子学的重要平台之一,基于能谷光子晶体的新型光波导支持抗散射传输的能谷依赖边界态,提高了波导中的急弯传输效率,为光信息高效传输提供了新思路.另一方面,对称性在拓扑学和光子晶体研究中具有重要的物理意义... 详细信息

能谷光子晶体是研究拓扑光子学的重要平台之一,基于能谷光子晶体的新型光波导支持抗散射传输的能谷依赖边界态,提高了波导中的急弯传输效率,为光信息高效传输提供了新思路.另一方面,对称性在拓扑学和光子晶体研究中具有重要的物理意义和研究价值.例如,能谷光子晶体在破缺空间反演对称性的情况下表现出类量子能谷霍尔效应.目前,大多数能谷光子晶体具有C3对称性,而具有更低对称性的能谷光子晶体是否能够支持拓扑光传输仍然需要研究.本文通过调整能谷光子晶体的原胞形貌,构建了低对称性能谷光子晶体,并研究了其边界态的传输特性.研究结果表明,相对于C3对称性能谷光子晶体,低对称性能谷光子晶体的光子禁带变窄,但其边界态仍然能够实现单向激发以及抗散射传输.这一发现丰富了拓扑光子结构的多样性,为在低对称性结构中寻找拓扑保护光传输行为提供了指导.

关键词：能谷光子晶体对称性拓扑光传输

Field Test of Optical and Electrical Fire Detectors in Simulated Fire Scenes in a Cable Tunnel

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Photonic Sensors 2014年第2期4卷 156-161页

作者： dian fan Hongjun DING Dorothy Y. WANG Desheng JIANG National Engineering Laboratory for Fiber Optic Sensing Technology Wuhan University of Technology Wuhan430070 China Shenyang Fire Research Institute Shenyang 110034 China Center for Photonics Technology Bradley Department of Electrical and Computer Engineering Virginia PolytechnicInstitute and State University Blacksburg VA 24061 USA

这份报纸论述火察觉者的三种类型的严峻的结果：电的热察觉到电报，光纤维拉曼温度察觉到察觉者，和光纤维布拉格栅栏(FBG ) 温度察觉到察觉者，在二模仿的火，在一个电报的场面掘。在有有限热放射和没有火焰的小规模的火，火警报仅仅... 详细信息

这份报纸论述火察觉者的三种类型的严峻的结果：电的热察觉到电报，光纤维拉曼温度察觉到察觉者，和光纤维布拉格栅栏(FBG ) 温度察觉到察觉者，在二模仿的火，在一个电报的场面掘。在有有限热放射和没有火焰的小规模的火，火警报仅仅来自直接与热来源一起联系的热传感器。在有大约 5

关键词：火灾探测器电缆隧道现场测试火灾场景模拟光纤布拉格光栅 FBG传感器电气

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光加热光纤光栅阵列液位测量方法研究

传感技术学报 2024年第6期37卷 959-966页

作者：戢雅典范典王宇琦周次明武汉理工大学光纤传感技术与网络国家工程研究中心湖北武汉430070 武汉理工大学信息工程学院湖北武汉430070

安全可靠的液位测量是现代工业领域的重要技术需求之一,提出一种基于光加热光纤光栅阵列的液位测量方法,即利用泵浦光加热掺钴光纤,控制温度场,利用光栅阵列测量温度场分布,由于气液导热性能的差别,气液界面处温度突变,从而确定液位。... 详细信息

安全可靠的液位测量是现代工业领域的重要技术需求之一,提出一种基于光加热光纤光栅阵列的液位测量方法,即利用泵浦光加热掺钴光纤,控制温度场,利用光栅阵列测量温度场分布,由于气液导热性能的差别,气液界面处温度突变,从而确定液位。实验中,将掺钴光纤与密集光栅阵列紧密固定在一起,将1.5 W的泵浦光输入衰减系数分别为0.71 dB/cm和0.28 dB/cm的掺钴光纤中,沿着光传播的方向,温度变化均呈指数函数衰减。液位测量的精度与范围由主要取决于泵浦光功率、掺钴光纤吸收系数,经对比最终选定0.28 dB/cm的掺钴光纤作为液位实验的加热光纤。实验测量了不同液位下的温度场分布,证明了利用测量温度分布来测量液位的可行性,液位变化范围0~88 mm以内的误差为2 mm。所提出的传感系统结构简单,成本低廉,在液位测量方面具有潜在的应用价值。

关键词：光纤传感技术液位测量布拉格光栅阵列光加热温度调制温度分布