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Ultra reliability and massive connectivity provision in integrated internet of military things(IoMT)based on tactical datalink 被引量:1
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作者 Li Bing Yating Gu +4 位作者 Lanke Hu Li Bowen Yang Lihua Jue Wang Yue Yin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期386-398,共13页
One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high reliability.In this regard,this pa... One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high reliability.In this regard,this paper presents a class of code-domain nonorthogonal multiple accesses(NOMAs)for uplink ultra reliable networking of massive IoMT based on tactical datalink such as Link-16 and joint tactical information distribution system(JTIDS).In the considered scenario,a satellite equipped with Nr antennas servers K devices including vehicles,drones,ships,sensors,handset radios,etc.Nonorthogonal coded modulation,a special form of multiple input multiple output(MIMO)-NOMA is proposed.The discussion starts with evaluating the output signal to interference-plus-noise(SINR)of receiver filter,leading to the unveiling of a closed-form expression for overloading systems as the number of users is significantly larger than the number of devices admitted such that massive connectivity is rendered.The expression allows for the development of simple yet successful interference suppression based on power allocation and phase shaping techniques that maximizes the sum rate since it is equivalent to fixed-point programming as can be proved.The proposed design is exemplified by nonlinear modulation schemes such as minimum shift keying(MSK)and Gaussian MSK(GMSK),two pivotal modulation formats in IoMT standards such as Link-16 and JITDS.Numerical results show that near capacity performance is offered.Fortunately,the performance is obtained using simple forward error corrections(FECs)of higher coding rate than existing schemes do,while the transmit power is reduced by 6 dB.The proposed design finds wide applications not only in IoMT but also in deep space communications,where ultra reliability and massive connectivity is a keen concern. 展开更多
关键词 Satellite network Deep space communications Internet of military things Non-orthogonal multiple access MIMO LINK-16 JITDS
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Themes of Earth Science Frontiers Issues
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《地学前缘》 EI CAS CSCD 北大核心 2008年第2期166-166,共1页
As of 2006 Earth Science Frontiers(ESF) is transitioning from a quarterly publication to bi-monthly publication.Each year,issues of ESF will be developed along three themes:
关键词 ESF themes of Earth Science Frontiers Issues
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Themes of Earth Science Frontiers Issues for 2007 and Beyond
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《地学前缘》 EI CAS CSCD 北大核心 2007年第3期101-101,共1页
As of 2006 Earth Science Frontiers (ESF) is transitioning from a quarterly publication to bi-monthly publication. Each year, from 2007 onwards, issues of ESF will be developed along three themes:1.Earth Materials for ... As of 2006 Earth Science Frontiers (ESF) is transitioning from a quarterly publication to bi-monthly publication. Each year, from 2007 onwards, issues of ESF will be developed along three themes:1.Earth Materials for Nos. 1 and 2.2.Earth Tectonics and Dynamics for Nos. 3 and 4.3.Earth Surface Processes for Nos. 5 and 6.'Earth Materials' will focus on the study of the Earth's composition, principally dealing with mineralogy and crystallography, petrology, fluids, mineral deposits and mineral exploration, and geochemistry.'Earth Tectonics and Dynamics' will focus on studies of displacement and deformation of lithosphere, including structural geology, regional tectonics and plate tectonics, continental dynamics, geophysics and tectonophysics.'Earth Surface Processes' will publish studies on the interactions and relationships between the lithosphere, the hydrosphere, the biosphere and the atmosphere. 展开更多
关键词 ESF themes of Earth Science Frontiers Issues for 2007 and Beyond
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Themes ofEarth Science Frontiersissues for 2007 and beyond
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《地学前缘》 EI CAS CSCD 北大核心 2006年第2期92-92,共1页
关键词 themes ofEarth Science Frontiersissues for 2007 and beyond
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Themes of Earth Science Frontiers Issues for 2007 and Beyond
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《地学前缘》 EI CAS CSCD 北大核心 2006年第6期226-226,共1页
关键词 themes of Earth Science Frontiers Issues for 2007 and Beyond
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Themes of Earth Science Frontiers issues for 2007 and beyond
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《地学前缘》 EI CAS CSCD 北大核心 2006年第4期173-173,共1页
As of 2006 Earth Science Frontiers(ESF)is transitioning from a quarterly publication to bimonthly publication.Each year ,from 2007 on wards ,issues of ESF will be developed along three
关键词 themes of Earth Science Frontiers issues for 2007 and beyond
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The International Transmission of Chinese Theme Documentaries in Recent Years
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作者 Wang Ning 《学术界》 CSSCI 北大核心 2018年第4期247-253,共7页
In recent years,documentaries of Chinese theme,including those shot by China,by foreign countries or jointly shot,are gaining more and more attention and favor.Through the on-the-spot record of Chinese nature,history,... In recent years,documentaries of Chinese theme,including those shot by China,by foreign countries or jointly shot,are gaining more and more attention and favor.Through the on-the-spot record of Chinese nature,history,humanity,social customs and ceremonies,as well as the present modern society in documentaries,by applying appropriate transmission strategies,audience all over the world can directly and concretely feel the Chinese history,nature and culture,touch the modern Chinese image,which influences and changes foreign audience’s understanding of China and exerts positive international transmission impacts. 展开更多
关键词 中国历史 国际传播 社会习俗 传播策略 射击 自然
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ResearchonsecureaccessmechanismininternetofthingsbasedonTePA 被引量:4
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作者 杨年鹏 龙昭华 +1 位作者 蒋贵全 马艳 《计算机工程与设计》 CSCD 北大核心 2012年第4期1305-1309,共5页
以椭圆曲线密码算法和三元对等鉴别架构为基础,通过对物联网的基本概念、体系结构的分析,提出了一种基于椭圆曲线签名、三元鉴别的物联网安全接入机制。该机制强化了对物联网中无线传感器节点的鉴别,要求通信的任何一方在通信前必须... 以椭圆曲线密码算法和三元对等鉴别架构为基础,通过对物联网的基本概念、体系结构的分析,提出了一种基于椭圆曲线签名、三元鉴别的物联网安全接入机制。该机制强化了对物联网中无线传感器节点的鉴别,要求通信的任何一方在通信前必须通过其它两方的身份验证。从性能和安全等方面分析了该机制的可行性和可靠性,增强了物联网下对接入访问的安全控制,从而对物联网的建设发展起到了一定的建言作用。 展开更多
关键词 物联网 无线传感器网络 安全接入 三元对等鉴别 椭圆曲线密码
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Interpreting the Theme of A Dance to the Music of Time from A Historical Perspective
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作者 Ning Ming 《学术界》 CSSCI 北大核心 2013年第12期277-282,共6页
A Dance to the Music of Timewritten by Anthony Powell consists of12books,in four volumes,which mainly writes about the life of the upper middle society between 1914and 1971in Britain.Since its coming into the world,th... A Dance to the Music of Timewritten by Anthony Powell consists of12books,in four volumes,which mainly writes about the life of the upper middle society between 1914and 1971in Britain.Since its coming into the world,the work and the writer himself have received a lot of public attention and acquired many awards.However,it’s not easy to interpret its theme because of the detached writing style and the relatively unstructured plot.So the agenda of the writer and the theme of the work can be truly understood only by exploring it from the historical perspective so that the polyphonic themes of the novel can be identified. 展开更多
关键词 舞蹈 音乐 历史 时间 非结构化 写作风格 作家 生活
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Somewhere This Side of the View from Nowhere: On the Phenomenological Prepredicative Grounding of the Idea of Objectivity
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作者 Andrea Altobrando 《学术界》 CSSCI 北大核心 2019年第1期197-211,共15页
Although objectivity is mainly accounted for in terms of linguistic thought and communication,in this article I will aim to showthat at least one condition of possibility for our understanding of objectivity is ground... Although objectivity is mainly accounted for in terms of linguistic thought and communication,in this article I will aim to showthat at least one condition of possibility for our understanding of objectivity is grounded on a prepredicative,i. e. pre-linguistic and pre-communicative,level. I will endorse a Husserlian viewpoint on the issue,and I will try to develop some aspects of the Husserlian account of three-dimensional thing-perception by means of which I will showhowprepredicative experience can actually offer us a fundamental element of our common understanding of objectivity. In doing this,it will be necessary to acknowledge thing-perception as being primarily intertwined with indeterminacy. I will claim that only on the basis of such an intuitive and prepredicative access to the things as partially indeterminate,first,and as determinable,second,is it possible to have an understanding of the world as something (at least partially) independent from the intuition (s) all subjects can have of it. By means of the addition of a consciousness of the thing as accessible to other subjects,one achieves a vision of the thing as fully determinate in itself. This"vision",however,takes one to be aware of the determination of the thing as lying beyond any intuitive grasp of it. The result will,thus,be that the prepredicative constitution of our basic sense of objectivity leads us to intend the world as something which should be accounted for (also) by means of sources different from intuition. 展开更多
关键词 OBJECTIVITY thing-perception prepredicative experience INDETERMINACY Husserlian EPISTEMOLOGY
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物联网中基于信任抗On-off攻击的自适应安全机制 被引量:6
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作者 张光华 杨耀红 +1 位作者 庞少博 陈振国 《计算机应用》 CSCD 北大核心 2018年第3期682-687,共6页
为了降低静态安全机制中不必要的数据源认证开销和防御信任阈值机制中存在的On-off攻击,在物联网(IoT)环境下提出了一种基于信任的自适应安全机制。首先,根据节点在信息交互中的行为表现建立节点间的信任评估模型,进而给出节点总体信任... 为了降低静态安全机制中不必要的数据源认证开销和防御信任阈值机制中存在的On-off攻击,在物联网(IoT)环境下提出了一种基于信任的自适应安全机制。首先,根据节点在信息交互中的行为表现建立节点间的信任评估模型,进而给出节点总体信任值的度量方法;然后,对于总体信任值高于信任阈值的节点,采用基于信任的自适应检测算法实时地检测这些节点总体信任值的变化情况;最终,中继节点根据自适应检测的结果决定是否验证接收到的消息。仿真实验结果和分析表明,该机制降低了中继节点的能量开销,同时对物联网中的On-off攻击起到较好的防御作用。 展开更多
关键词 物联网 on-off攻击 信任评估 自适应安全 能耗
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论Internet与Internet of Things 被引量:2
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作者 曾华燊 《计算机应用》 CSCD 北大核心 2012年第4期893-899,共7页
从Internet发展历史及应用环境变化的角度讨论IoT(Internet of Things)提出背景、内涵、组成结构和体系结构等关键问题。在分析对IoT的典型定义的基础上,笔者认为"ITU把IoT作为Internet平台在应用领域实现人、机、和智能化物理对象... 从Internet发展历史及应用环境变化的角度讨论IoT(Internet of Things)提出背景、内涵、组成结构和体系结构等关键问题。在分析对IoT的典型定义的基础上,笔者认为"ITU把IoT作为Internet平台在应用领域实现人、机、和智能化物理对象(SPO)信息全方位互通和实践普适计算理念的下一代Internet及其应用系统的概括"是对IoT更为合理的广义定义。以该定义为基础,全面地分析了"由多个用户域网(CPN)通过骨干通信子网互联"的基本组成结构,讨论了两类SPO-CPN的基本组成结构及其支撑技术;指出SPO的引入主要影响CPN资源网络中的接入部分,属于应用系统的范畴,对Internet基本技术影响甚微。笔者不赞同以欧盟为代表的把IoT定义为联物专用网的狭义定义,指出其IoT模型和体系结构研究混淆了网络平台与应用系统,实质上是网络应用系统模型和体系结构。 展开更多
关键词 智能化物理对象 IOT 物联网 全联网
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一种基于ThemeRiver模型的非连续层次数据可视化方法 被引量:7
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作者 甄远刚 陈谊 +1 位作者 刘莹 刘瑞军 《系统仿真学报》 CAS CSCD 北大核心 2015年第10期2460-2466 2474,2474,共8页
针对传统Theme River模型对非连续数据特征表现支持较差的问题,提出一种改进的非连续数据Theme River可视化方法。对数据点划分时间段分别进行统计,补充新的数据点,构造数据点集,利用高斯模型曲线拟合,经过主题布局排序,颜色选择,标签... 针对传统Theme River模型对非连续数据特征表现支持较差的问题,提出一种改进的非连续数据Theme River可视化方法。对数据点划分时间段分别进行统计,补充新的数据点,构造数据点集,利用高斯模型曲线拟合,经过主题布局排序,颜色选择,标签分布布局成一种具有预测功能且能够展示层次特征的新型主题河流模型。在层次结构上,利用相同颜色序列表示同层次数据。将该方案应用于农残数据中,有助于对一段时间内的农残数据进行有效监测,为农药残留预测预警提供依据。 展开更多
关键词 信息可视化 层次数据 主题河流 农残数据 时间序列
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Theme方法在C^4ISR系统需求建模中的应用
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作者 张佩 陈洪辉 +1 位作者 刘俊先 舒振 《火力与指挥控制》 CSCD 北大核心 2010年第9期22-25,共4页
针对C4ISR系统需求建模对系统开发的重要性和系统非功能需求描述不完善的现状,引入Theme方法,即以面向方面的分析方法对C4ISR系统进行需求建模,在DoDAF产品的基础上用面向方面的分析方法对C4ISR系统需求开发。这种方法可有效弥补面向对... 针对C4ISR系统需求建模对系统开发的重要性和系统非功能需求描述不完善的现状,引入Theme方法,即以面向方面的分析方法对C4ISR系统进行需求建模,在DoDAF产品的基础上用面向方面的分析方法对C4ISR系统需求开发。这种方法可有效弥补面向对象的需求建模方法对非功能需求建模的缺陷,也有助于映射和影响后续的体系结构设计,为系统开发打下良好的基础。 展开更多
关键词 需求工程 C4ISR系统 theme 面向方面 非功能需求
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Free-walking:Pedestrian inertial navigation based on dual foot-mounted IMU 被引量:2
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作者 Qu Wang Meixia Fu +6 位作者 Jianquan Wang Lei Sun Rong Huang Xianda Li Zhuqing Jiang Yan Huang Changhui Jiang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期573-587,共15页
The inertial navigation system(INS),which is frequently used in emergency rescue operations and other situations,has the benefits of not relying on infrastructure,high positioning frequency,and strong real-time perfor... The inertial navigation system(INS),which is frequently used in emergency rescue operations and other situations,has the benefits of not relying on infrastructure,high positioning frequency,and strong real-time performance.However,the intricate and unpredictable pedestrian motion patterns lead the INS localization error to significantly diverge with time.This paper aims to enhance the accuracy of zero-velocity interval(ZVI)detection and reduce the heading and altitude drift of foot-mounted INS via deep learning and equation constraint of dual feet.Aiming at the observational noise problem of low-cost inertial sensors,we utilize a denoising autoencoder to automatically eliminate the inherent noise.Aiming at the problem that inaccurate detection of the ZVI detection results in obvious displacement error,we propose a sample-level ZVI detection algorithm based on the U-Net neural network,which effectively solves the problem of mislabeling caused by sliding windows.Aiming at the problem that Zero-Velocity Update(ZUPT)cannot suppress heading and altitude error,we propose a bipedal INS method based on the equation constraint and ellipsoid constraint,which uses foot-to-foot distance as a new observation to correct heading and altitude error.We conduct extensive and well-designed experiments to evaluate the performance of the proposed method.The experimental results indicate that the position error of our proposed method did not exceed 0.83% of the total traveled distance. 展开更多
关键词 Indoor positioning Inertial navigation system(INS) Zero-velocity update(ZUPT) Internet of things(IoTs) Location-based service(LBS)
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基于5DOF的隧道摄像头清洗装置控制系统设计
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作者 边艳妮 杨雨升 +3 位作者 王超 张军 叶敏 刘晓娜 《中国工程机械学报》 北大核心 2024年第2期214-219,共6页
针对隧道内摄像头镜面污染严重,影响隧道监控管理的问题,基于高压水射流技术,提出了一种5自由度的机械臂清洗装置。分析系统的功能需求,采用电驱动的方式对机械臂的控制系统进行设计,基于比例积分微分控制(PID)原理设计了各关节的定位功... 针对隧道内摄像头镜面污染严重,影响隧道监控管理的问题,基于高压水射流技术,提出了一种5自由度的机械臂清洗装置。分析系统的功能需求,采用电驱动的方式对机械臂的控制系统进行设计,基于比例积分微分控制(PID)原理设计了各关节的定位功能,并用物联网监控的方式开发了远程APP测控系统。通过室内实验确定了最优的清洗工艺参数,并进行了现场的清洗实验。实验结果表明:其能够实现隧道摄像头镜面的有效清洗,清洗装置各关节的定位相对误差在1.4%以内,为隧道内摄像头或者标识物的清洗提供了安全高效的机械化方式。 展开更多
关键词 隧道清洗 控制系统 机械臂 高压水射流 物联网
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Cloud control for IIoT in a cloud-edge environment 被引量:1
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作者 YAN Ce XIA Yuanqing +1 位作者 YANG Hongjiu ZHAN Yufeng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期1013-1027,共15页
The industrial Internet of Things(IIoT)is a new indus-trial idea that combines the latest information and communica-tion technologies with the industrial economy.In this paper,a cloud control structure is designed for... The industrial Internet of Things(IIoT)is a new indus-trial idea that combines the latest information and communica-tion technologies with the industrial economy.In this paper,a cloud control structure is designed for IIoT in cloud-edge envi-ronment with three modes of 5G.For 5G based IIoT,the time sensitive network(TSN)service is introduced in transmission network.A 5G logical TSN bridge is designed to transport TSN streams over 5G framework to achieve end-to-end configuration.For a transmission control protocol(TCP)model with nonlinear disturbance,time delay and uncertainties,a robust adaptive fuzzy sliding mode controller(AFSMC)is given with control rule parameters.IIoT workflows are made up of a series of subtasks that are linked by the dependencies between sensor datasets and task flows.IIoT workflow scheduling is a non-deterministic polynomial(NP)-hard problem in cloud-edge environment.An adaptive and non-local-convergent particle swarm optimization(ANCPSO)is designed with nonlinear inertia weight to avoid falling into local optimum,which can reduce the makespan and cost dramatically.Simulation and experiments demonstrate that ANCPSO has better performances than other classical algo-rithms. 展开更多
关键词 5G and time sensitive network(TSN) industrial Internet of things(IIoT)workflow transmission control protocol(TCP)flows control cloud edge collaboration multi-objective optimal scheduling
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复兴并重构无体物的概念以实现财产法的现代化 被引量:2
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作者 徐国栋 《法治研究》 北大核心 2025年第1期15-32,共18页
在斯多亚哲学中,无体物作为准存在与作为存在的有体物一起构成世界的全景。罗马人把有体无体的概念引进到法学后,把它降等为物的第一分类依据。盖尤斯把无体物的概念改造为以权利为客体,服务于营造大物法体系的目的。由于无体物概念与... 在斯多亚哲学中,无体物作为准存在与作为存在的有体物一起构成世界的全景。罗马人把有体无体的概念引进到法学后,把它降等为物的第一分类依据。盖尤斯把无体物的概念改造为以权利为客体,服务于营造大物法体系的目的。由于无体物概念与近代法上的绝对权相对权区分论以及权利与其客体区分论直接抵触,在法典编纂时代,除了一些忠诚于罗马法的民法典保留了无体有体的物的分类外,许多民法典放弃了这一分类,把动产不动产作为物的第一分类,并营造了物债两分的财产法体系。随着这种两分的缺陷得到揭示以及工业革命造成的能量等不能为有体物的概念涵盖的客体的出现,无体物的概念得到复兴,一些过去不规定无体物的民法典改为规定之。由于民法概念的去哲学化,无体财的概念开始取代无体物的概念。由于知识产权的蓬勃发展,非物质财的概念进一步取代了无体财的概念。我国《民法典》保留了无体物的存在空间,但它仅承认权利无体物,并以法律有明文规定者为限,造成它对自身规定的个人信息、数据、无线电频谱资源、空间等新兴非物质财不能以无体物的概念涵盖之。只有把我国《民法典》承认的无体物解释成也包括非权利无体物,才能实现我国财产法的现代化,以妥善应对民法客体的非物质化和权利的所有权客体化两大趋势。 展开更多
关键词 无体物 无体财 非物质财 半无体物 个人信息 数据 财产法现代化
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突发事件网络舆情主题演化聚焦特征研究——以“河南暴雨事件”为例 被引量:1
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作者 李燕凌 伍可欣 《灾害学》 北大核心 2025年第1期207-212,共6页
通过生命周期理论,对突发事件网络舆情情感变化推动主题演化聚焦的特征进行分阶段研究,有利于了解政府和媒体如何进行突发事件网络舆情引导。该文以“河南暴雨事件”为例,运用情感词典识别各阶段情感倾向,运用LDA模型分析各阶段舆情主题... 通过生命周期理论,对突发事件网络舆情情感变化推动主题演化聚焦的特征进行分阶段研究,有利于了解政府和媒体如何进行突发事件网络舆情引导。该文以“河南暴雨事件”为例,运用情感词典识别各阶段情感倾向,运用LDA模型分析各阶段舆情主题,结合生命周期理论划分舆情生命周期,总结突发事件网络舆情情感变化推动主题随生命周期演化聚焦的特征。研究表明,在潜伏期和萌动期,网民情感由负面转向中性,主题聚焦于应急保障;加速期和成熟期,情感由负面转向正面,主题关注应急救援;消退期,情感以中性和正面为主,主题转向应急修复。政府和媒体在各阶段有效引导了舆情。研究为舆情监管部门提供了网民情感变化与主题演化的洞察,为提高舆情引导能力提供了方法指导。 展开更多
关键词 突发事件 网络舆情 主题演化
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面源污染智慧监管的破局方案:从精准观测到精细管理 被引量:1
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作者 熊俊峰 林晨 +3 位作者 黄佳聪 陈沐松 谢晖 马荣华 《中国生态农业学报(中英文)》 北大核心 2025年第2期203-217,共15页
农业面源污染不仅造成了地表水环境恶化,而且严重制约了农业绿色可持续发展,近年来愈发得到各部门高度重视,相关监测方案和管理体系逐步建立,但是仍存在面源污染治理成效较低的问题。本文总结了面源污染监测在不同尺度下的监测对象、时... 农业面源污染不仅造成了地表水环境恶化,而且严重制约了农业绿色可持续发展,近年来愈发得到各部门高度重视,相关监测方案和管理体系逐步建立,但是仍存在面源污染治理成效较低的问题。本文总结了面源污染监测在不同尺度下的监测对象、时空精度、污染源识别方案和管理措施现状,指出了监测精度不足、污染源识别动态性不足、污染源和管理措施匹配性不足的瓶颈,这也直接或间接导致面源污染监测体系不健全、智能化不足、精细化程度较低和污染治理效率较低等问题。随着信息化和数字化发展,物联网平台通过集成天空地一体化监测设备与算法,成为智能化监管的关键抓手,为面源污染精细化监测提供了技术支撑,构建农业面源污染物联网智能观测体系,解决模型关键参数观测精度问题,利用“面源污染模型+指纹示踪”的面源多污染源识别与追踪技术体系,解决污染源精准定位问题,考虑多污染源和多治理模式的成效评估及方案优选,解决精准化和差别化治理问题。最终实现面源管控的系统性、集成性和智能性水平提升,打通从“监测”到“治理”的关键突破路径。物联网智能监测平台应用与示范在太湖流域逐步开展,为农业面源污染智慧监管破局提供了重要参考。 展开更多
关键词 面源污染 物联网 智能监管 多目标配置
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