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面向地理流的双变量时空扫描统计方法

测绘科学 2024年第1期49卷 204-215页

作者：王钰辉阳孟杰周梦杰周楷淳湖南师范大学地理科学学院长沙410081 地理空间大数据挖掘与应用湖南省重点实验室长沙410081 湖南师范大学“城乡转型过程与效应”重点实验室长沙410081

针对现有的地理流双变量异常聚类方法忽视了时间维度的问题,提出面向地理流的双变量时空扫描统计方法。先构建面向地理流的多尺度时空扫描窗口;通过伯努利模型下的扫描统计量检测窗口中是否存在异常流簇,采用蒙特卡洛模拟方法检验扫描... 详细信息

针对现有的地理流双变量异常聚类方法忽视了时间维度的问题,提出面向地理流的双变量时空扫描统计方法。先构建面向地理流的多尺度时空扫描窗口;通过伯努利模型下的扫描统计量检测窗口中是否存在异常流簇,采用蒙特卡洛模拟方法检验扫描统计量的统计显著性;筛选一系列时空分布无重叠的异常流簇。应用该方法识别厦门市网约车流和巡游车流的时空异常流簇,以发现两类出租车竞争模式的时空格局。结果表明:巡游车流占优簇常发生在凌晨,分布在娱乐、餐饮、住宿等场所;网约车流占优簇常发生在上午或傍晚,分布在办公地点与居住地之间。该方法挖掘的结果能够发现异常流簇准确的时空分布特征,可为城市交通规划提供支持。

关键词：地理流双变量异常流聚类时空扫描统计时空分布差异

影视导演课程思政建设的学理要义、问题困境与践行向度研究

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林区教学 2024年第1期 33-36页

作者：周孟杰长沙学院马栏山新媒体学院长沙410000

课程思政既是一种思想政治教育方式,也是落实三全育人的创新实践。育人与铸魂同向、修德与精业共生、践行与治学相融是作为影视导演课程思政建设的学理逻辑与路径关键。在教学实践过程中,教书与育人认知关系脱节分裂、思政教育与专业知... 详细信息

课程思政既是一种思想政治教育方式,也是落实三全育人的创新实践。育人与铸魂同向、修德与精业共生、践行与治学相融是作为影视导演课程思政建设的学理逻辑与路径关键。在教学实践过程中,教书与育人认知关系脱节分裂、思政教育与专业知识融合存在难度、激励制度与监督评价体系存在缺位是阻碍影视导演课程思政建设的三大问题。要促进影视导演课程与其他课程之间的资源互补,拓展思政教育与红色革命素材的同频共振,形成具有激励和动态特征的评估体系,推动多元主体参与的影视导演课程思政建设常态评估体系,进而提升和拓展影视导演课程思政建设的理念、方法与途径。

关键词：思想政治教育影视导演主流电影

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面向地理流的时空交叉K函数方法

测绘学报 2024年第8期53卷 1644-1655页

作者：周梦杰阳孟杰陈慧颖田雨萌万义良夏吉喆湖南师范大学地理科学学院湖南长沙410081 地理空间大数据挖掘与应用湖南省重点实验室湖南长沙410081 湖南师范大学城乡转型过程与效应重点实验室湖南长沙410081 深圳大学建筑与城市规划学院广东深圳518060 广东省城市空间信息工程重点实验室广东深圳518060

地理流表示地理对象在不同地理位置之间有意义的交互或移动。挖掘地理流时空关联模式,对于揭示地理流之间的时空依赖性和异质性,理解地理流的发生机制和时空交互作用具有重要意义。目前,地理流空间关联分析方法日益增多,但鲜有研究考虑... 详细信息

地理流表示地理对象在不同地理位置之间有意义的交互或移动。挖掘地理流时空关联模式,对于揭示地理流之间的时空依赖性和异质性,理解地理流的发生机制和时空交互作用具有重要意义。目前,地理流空间关联分析方法日益增多,但鲜有研究考虑地理流的时空耦合特征并关注时间效应对探测模式的影响,准确捕捉地理流之间依赖关系的时空演变趋势仍是当前领域的难点问题。因此,本文扩展点模式时空交叉K函数,提出了地理流的时空交叉K函数,该函数以地理流整体为研究对象,用于探测两类地理流事件之间的时空关联模式。全局时空交叉K函数可探测研究区域中整体地理流关联模式,而局部时空交叉K函数可以识别不遵循全局趋势的在局部尺度上的时空关联情况。本文采用地理流时空交叉K函数的方法对厦门岛巡游车和网约车流数据进行了时空关联分析,揭示了两类车辆流的全局和局部时空竞争格局。全局结果表明,两类车辆呈排斥模式,说明在厦门岛整体上两类车辆之间并未出现激烈的正面竞争;而局部结果显示,在早、午、晚高峰期,巡游车流和网约车流在某些局部区域仍存在竞争,且主要分布在居民区—产业园、居民区—机场、火车站—商圈、商圈—旅游景点等区域之间。

关键词：地理流时空关联模式时空交叉K函数网约车服务巡游车服务

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Induction Motor Fault Diagnosis Based on Transfer Principal Component Analysis

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Chinese Journal of Electronics 2021年第1期30卷 18-25页

作者： YAN Ruqiang SHEN Fei zhou mengjie School of Mechanical Engineering Xi'an Jiaotong University School of Instrument Science and Engineering Southeast University

This paper presents a transfer learning-based approach for induction motor fault diagnosis,where the Transfer principal component analysis(TPCA)is proposed to improve diagnostic performance of the induction motors under various working conditions. TPCA is developed to minimize the distribution difference between training and testing data by mapping cross-domain data into a shared latent space in which domain difference can be reduced. The trained model can achieve a good performance in testing data by using the learned features consisting of common latent principal components. Experimental results show that the proposed approach outperforms traditional machine learning techniques and can diagnose induction motor fault under various working conditions effectively.

关键词： Fault diagnosis Transfer principal component analysis Transfer learning Various working conditions Induction motors

一体两翼四融合:AI背景下新媒体人才培养模式研究

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长沙大学学报 2024年第3期38卷 97-102页

作者：张世英周孟杰长沙学院马栏山新媒体学院湖南长沙410022

当前数字信息技术快速更迭,新媒体行业急需兼具弘扬正气的舆论引导能力、适应市场生态的创意传播能力、顺应科技变革的技术实践能力的新媒体复合型人才。这既是新媒体人才培养契合媒体机构数智化转型的时代指向,也是音视频产业与全媒体... 详细信息

当前数字信息技术快速更迭,新媒体行业急需兼具弘扬正气的舆论引导能力、适应市场生态的创意传播能力、顺应科技变革的技术实践能力的新媒体复合型人才。这既是新媒体人才培养契合媒体机构数智化转型的时代指向,也是音视频产业与全媒体多场景应用的现实需求和主流媒体融合向纵深发展的内在要求,更是高校教育建设发展的客观需要。通过建构“一体两翼四融合”的新媒体复合型人才培养模式,促进高校建设与地方发展有机深度融合,推动专业链、产业链、人才链贯通互动,实现产学研协同育人平台的边界突破与多元主体的价值共创。

关键词：新媒体人才复合型人才现代产业学院科技赋能跨界融合

中草药饲料添加剂在养猪生产中的应用研究进展

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黑龙江畜牧兽医 2024年第13期 22-26页

作者：司雨豪钟琦周梦洁周建红蒋思文柴进华中农业大学动物科学技术学院武汉430070 当阳市畜牧兽医中心湖北当阳444100

中草药具有毒副作用小、耐药性较低、产品残留量低、经济环保且高效安全的优点,是在抗生素逐渐被限制使用后养猪生产上优秀的“替抗”饲料添加剂。文章从中草药饲料添加剂对生猪免疫机能、疾病防控、生长性能和繁殖性能影响等方面阐述... 详细信息

中草药具有毒副作用小、耐药性较低、产品残留量低、经济环保且高效安全的优点,是在抗生素逐渐被限制使用后养猪生产上优秀的“替抗”饲料添加剂。文章从中草药饲料添加剂对生猪免疫机能、疾病防控、生长性能和繁殖性能影响等方面阐述了中草药饲料添加剂在养猪生产上的应用及优势,以期为生产实践提供指导。

关键词：中草药猪免疫机能疾病防控生长性能繁殖性能

Computationally Efficient Direction of Arrival Estimation for Improved Nested Linear Array

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第6期36卷 1018-1025页

作者： LIN Xinping zhou mengjie ZHANG Xiaofei LI Jianfeng College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

Nested linear array enables to enhance localization resolution and achieve under-determined direction of arrival(DOA)*** this paper,the traditional two-level nested linear array is improved to achieve more degrees of freedom(DOFs)and better angle estimation ***,a computationally efficient DOA estimation algorithm is *** discrete Fourier transform(DFT)method is utilized to obtain coarse DOA estimates,and subsequently,fine DOA estimates are achieved by spatial smoothing multiple signals classification(SS-MUSIC)*** to SS-MUSIC algorithm,the proposed algorithm has the same estimation accuracy with lower computational complexity because the coarse DOA estimates enable to shrink the range of angle spectral *** addition,the estimation of the number of signals is not required in advance by DFT *** simulation results testify the effectiveness of the proposed algorithm.

关键词： DOA estimation nested linear array DOFs SS-MUSIC algorithm computational complexity

Low-Voltage Activating, Fast Responding Electro-thermal Actuator Based on Carbon Nanotube Film/PDMS Composites

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Advanced Fiber Materials 2021年第1期3卷 38-46页

作者： Mohamed Amine Aouraghe zhou mengjie Yiping Qiu Xu Fujun Shanghai Key Laboratory of Lightweight Composite Donghua UniversityShanghai 201620China College of Textiles Donghua UniversityShanghai 201620China

The electro-thermal actuators(ETA)are smart devices that can convert electric energy into mechanical energy under electro-heating stimulation,showing great potential in the fields of soft robotics,artificial muscle and aerospace *** this study,to build a low-voltage activating,fast responding ETA,a robust and flexible carbon nanotube film(CNTF)with excellent electrical and thermal conductivity was adopted as the conductive ***,an asymmetric bilayer structured ETA was manufactured by coating a thin layer of polydimethylsiloxane(PDMS)with high coefficient of thermal expansion(9.3×10^(-4)℃^(−1)),low young’s modulus(2.07 MPa)on a thin CNTF(~11μm).The as-produced CNTF/PDMS composite ETA exhibited a large deformation(bending angle~324°)and high electro heating performance(351℃)at a low driving voltage of 8 V within~12 *** actuated movement and the generated heat could be controlled by adjusting the driving voltages and showed almost the same values in 20 ***,the influences of the PDMS thickness and driving voltage on CNTF/PDMS composite ETA performance were systematically *** CNTF/PDMS soft robotic hand which can lift 5.1 times and crab 1.3 times of its weight demonstrated its potential capability.

关键词： Carbon nanotube film PDMS Actuator Multifunctional composite Soft robotic

Simultaneously enhancing capacity and security in free-space optical chaotic communication utilizing orbital angular momentum

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Photonics Research 2023年第12期11卷 2185-2193页

作者： YIQUN ZHANG MINGFENG XU MINGBO PU mengjie zhou JIAZHENG DING SHUANGCHENG CHEN KUN QIU NING JIANG XIANGANG LUO School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China State Key Laboratory of Optical Technologies on Nano-Fabrication and Micro-Engineering Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China Research Center on Vector Optical Fields Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China School of Optoelectronics University of Chinese Academy of SciencesBeijing 100049China Tianfu Xinglong Lake Laboratory Chengdu 610299China

Optical chaotic signals emitted from an external-cavity feedback or injected laser diode enable small-signal information concealment in a noise-like carrier for secure optical *** to the chaotic bandwidth limitation resulting from intrinsic relaxation oscillation frequency of lasers,multiplexing of optical chaotic signal,such as wavelength division multiplexing in fiber,is a typical candidate for high-capacity secure ***,to our best knowledge,the utilization of the spatial dimension of optical chaos for free-space secure communication has not yet been ***,we experimentally demonstrate a free-space all-optical chaotic communication system that simultaneously enhances transmission capacity and security by orbital angular momentum(OAM)*** chaotic signals with two different OAM modes totally carrying 20 Gbps on-off keying signals are secretly transmitted over a 2 m free-space link,where the channel crosstalk of OAM modes is less than-20 d B,with the mode spacing no less than *** receiver can extract valid information only when capturing approximately 92.5% of the OAM beam and correctly demodulating the corresponding *** error rate below the 7%hard-decision forward error correction threshold of 3.8×10^(-3)can be achieved for the intended ***,a simulated weak turbulence is introduced to comprehensively analyze the influence on the system performance,including channel crosstalk,chaotic synchronization,and transmission *** work may inspire structured light application in optical chaos and pave a new way for developing future high-capacity free-space chaotic secure communication systems.

关键词： communication chaotic momentum