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CSEE Journal of Power and Energy Systems 2021年第4期7卷 875-888页

作者： Zichen He junyu zhu Jie zhu Xingming Bian Boyang Shen State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China State Grid Suzhou Power Supply Company Suzhou 215000Jiangsu ProvinceChina Electrical Engineering Division University of CambridgeCambridge CB30FAUK

As the effect of climate plays a significant role in corona discharge under combined voltages,the variation of corona inception voltage with different air pressure and humidities is *** experimental platform,based on a rod-to-plane electrode,is constructed with adjustable air pressure from 0.06 MPa to 0.10 MPa and with a relative humidity(RH)from 20%to 90%.The variation of ultraviolet(UV)photon count and corona inception voltage is obtained at various climate conditions under different applied voltages:the single AC,single DC,and combined *** turns out that all the corona inception voltages decline with the drop of air pressure and the rise of humidity under different applied *** influence between different voltages primarily relies on space charge,as more AC components make it easier to accumulate positive *** existence of AC makes ions move forward and backward while the existence of DC dominates the polarity of corona and general drift *** last the fitting formula of hybrid corona inception voltage combining air pressure and relative humidity is given.

关键词： Air pressure combined AC and DC voltages corona discharge humidity inception voltage

Impact of Accumulated Temperature on Wetland Vegetation Area in Poyang Lake

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Computers, Materials & Continua 2022年第10期73卷 1915-1926页

作者： Xin Yao junyu zhu Hong Zeng Wenzheng Yu Hanxiaoya Zhang School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing210044China Cold and Arid Regions Environmental and Engineering Research Institute CASLanzhou730000China Faculty of Science The University of Auckland1010New Zealand

Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang *** research used the classification and regression tree(CART)to classify normalized vegetation area index derived from MODIS LAI(Moderate Resolution Imaging Spectroradiometer Leaf Area Index)images from 2008 to 2014,according to different climate indexes,such as mean daily air temperature(n),accumulated temperature(jw),daily maximum temperature(g),daily minimum temperature(d),accumulative precipitation(j),water level(s)and average water level for 20 days preceding(a).The results showed that:(1)The accumulated temperature and the 20-day average WL(water level)were found to have the greatest impact on variation in wetland vegetation area,and they both dominated the classification process twice;(2)Two classification thresholds of accumulated temperature were 790°C and 1784°C,approximately corresponding to the beginning of April and midMay;(3)790°C could also be used as a threshold to select remote sensing images to analysis the annual variability of vegetation,*** accumulated temperature is lower than 790°C,remote sensing images of similar accumulated temperature rather than similar date should be selected from different years for *** also found that,effects of different hydrological factors on area of floodplain grasslands showed stage characteristics:(1)From January to March,water level changes slowly with less rainfall,as a result,the 20-day average WL which can interpret the hydrologic characteristics smoothly showed significant importance in this stage;(2)While entering April,intense rainfall make accumulative precipitation to be the dominating factor of classification;(3)From late April to mid-May,in condition of accumulative precipitation higher than 405 mm,daily water level is of most importance,because to the flood recessio

关键词： Poyang Lake wetlands MODIS LAI CART model accumulated temperature water level

Humidity effects on the ground-level resultant electric field of positive DC conductors

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Plasma Science and Technology 2019年第7期21卷 6-15页

作者： Haibing LI Jie zhu Wei YANG Xu ZHANG Donglai WANG junyu zhu Xingming BIAN State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206People’s Republic of China State Key Laboratory of Advanced Transmission Technology Global Energy Interconnection Research InstituteBeijing 102211People’s Republic of China State Grid Suzhou Electric Power Supply Company Suzhou 215008People’s Republic of China

The effects of humidity on the ground-level resultant electric field around positive DC conductors were studied both experimentally and numerically. Experiments were carried out in an artificial climate chamber, the results of which showed that the photon count and the groundlevel resultant electric field strength both increased with increasing relative humidity. Numerical calculations for different values of relative humidity were carried out, including solutions of the positive corona inception voltage and the ion-flow field, for which a photoionization model and the upstream finite element method were employed, respectively. In order to analyze the effects of humidity, three main factors were considered: the ionization coefficient, the attachment coefficient in the photoionization model and the modified ion mobility of the charged water particles. The results indicated that, with increasing relative humidity, increasing values of the effective ionization coefficient were responsible for a reduction in the inception voltage, and the reduction reinforced the ground-level resultant electric field. Moreover, due to the charged water particles and the lower ion mobility with increasing relative humidity, the space charge density distribution was enhanced, which also strengthened the ground-level resultant electric field.

关键词： corona discharge humidity electric field

The role of low air pressure in the variation of negative corona-generated space charge in a rod to plane electrode

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High Voltage 2018年第2期3卷 126-132页

作者： Bian XingMing zhu junyu Yang Wei Wan ShuWei Qi Lei Li XueBao Li HaiBing State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206People's Republic of China State Key Laboratory of Advanced Transmission Technology Global Energy Interconnection Research InstituteBeijing 102211People's Republic of China State Grid Chongqing Nan'an Power Supply Company Chongqing 400060People's Republic of China

The corona-generated space charge may vary in different air pressures,and the quantitative law between the corona-generated space charge density and air pressure has never been *** work utilised computational approaches to explore the role of air pressure in the variation of negative corona-generated space charge.A negative fluid model in which the air pressure could be varied was built up to calculate the charged-particle density and electric field under different applied *** continuity equations were solved by flux corrected transport algorithm and the Poisson equation was computed by the successive over relaxation *** variations of important parameters due to air pressure were *** particles densities of electrons,positive ions and negative ions at standard and low atmosphere pressures were computed,which increased markedly due to the decrease of atmosphere *** fixed applied voltages,the exponential decay law between the maximal values of electron/positive ion densities at the head of the streamer and air pressure could be *** quantitative law between the maximal values of electron/positive ion densities at the head of the streamer and the applied voltage,relative air density was also achieved.

关键词： method charge maximal

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论“套话”在形象学研究中的功能和意义

语言与文化研究

语言与文化研究 2025年第1期33卷 237-240页

作者：祝君宇河南大学开封475000

近年来,形象学研究逐渐延伸到比较文学的领域,指向了一个跨学科的文学研究方向——比较文学形象学,而“套话”是其研究的一个重点内容。文章通过梳理套话的概念和生成过程,进一步探讨了其在形象学研究中的发展与传播,主要围绕套话的“... 详细信息

近年来,形象学研究逐渐延伸到比较文学的领域,指向了一个跨学科的文学研究方向——比较文学形象学,而“套话”是其研究的一个重点内容。文章通过梳理套话的概念和生成过程,进一步探讨了其在形象学研究中的发展与传播,主要围绕套话的“时间性”和文化误读现象展开分析,反思了在现代文化语境下如何正确认识他者的问题,最终落脚在中国形象的建构上,侧面突出了“套话”在形象学研究中的重要功能和意义。

关键词：比较文学形象学套话文化误读中国形象

纤维增强复合材料缠绕管桩弯曲冲击吸能试验与模拟

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振动与冲击 2024年第13期43卷 299-305页

作者：姚昱方海祝露朱俊羽南京工业大学土木工程学院南京211816

纤维增强复合材料(fiber reinforced polymer, FRP)具有较高的比强度、优异的耐腐蚀性、灵活的可设计性等优点。为解决桥梁防船撞难题,提出一种缠绕成型的FRP管桩抵御船舶撞击。分别改变管桩的壁厚、缠绕角度和冲击能量,开展弯曲冲击试... 详细信息

纤维增强复合材料(fiber reinforced polymer, FRP)具有较高的比强度、优异的耐腐蚀性、灵活的可设计性等优点。为解决桥梁防船撞难题,提出一种缠绕成型的FRP管桩抵御船舶撞击。分别改变管桩的壁厚、缠绕角度和冲击能量,开展弯曲冲击试验,对比分析各试件的破坏模式、动力时程响应及撞击过程中能量耗散情况。结果表明,纤维缠绕角度会改变试件的破坏模式,±75°缠绕角度的试件发生了剪切破坏,而±45°缠绕角度的试件仅在冲击区域发生局部破坏,且能恢复变形;增大壁厚能有效减小试件变形,但撞击力峰值会随之增大。采用ANSYS/LS-DYNA建立了冲击试验模型并进行有限元分析,数值模拟结果与试验值吻合较好。

关键词：冲击试验复合材料(FRP) 破坏模式吸能特性数值模拟

无人机辅助车联网环境下干扰感知的节点接入机制

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通信学报 2019年第6期40卷 90-101页

作者：范茜莹黄传河朱钧宇文少杰武汉大学计算机学院湖北武汉430072 工业和信息化部计算机与微电子发展研究中心(中国软件评测中心) 北京100081

在车联网中,链路频繁切换和信道干扰会导致传输时延增加及网络吞吐量下降。引入无人机与地面车辆进行协同通信,构建无人机辅助的空地一体化车联网,采用发送端自主决策的分布式策略,提出了一种干扰感知的节点接入机制。将节点接入问题形... 详细信息

在车联网中,链路频繁切换和信道干扰会导致传输时延增加及网络吞吐量下降。引入无人机与地面车辆进行协同通信,构建无人机辅助的空地一体化车联网,采用发送端自主决策的分布式策略,提出了一种干扰感知的节点接入机制。将节点接入问题形式化为一个与链路传输速率、链路切换次数和节点发射功率相关的多目标优化问题,利用对偶分解法将该问题分解为2个凸优化子问题:联合优化链路切换次数与链路传输速率和在保证链路可靠性的前提下优化节点发射功率。仿真实验表明了所提出节点接入机制可有效地改善数据传递率、平均端到端时延以及网络吞吐量。

关键词：车联网无人机干扰感知链路切换

城市环境车联网中基于近似算法的RSU部署方案

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通信学报 2018年第1期39卷 78-89页

作者：朱钧宇黄传河范茜莹覃匡宇付斌武汉大学计算机学院湖北武汉430072 美国得克萨斯里奥格兰德河谷大学得克萨斯爱丁堡78539

为了使用尽可能少的RSU实现对目标区域的有效覆盖,设计c街道模型,将对区域的覆盖转化为对区域内街道的覆盖,然后,在该模型下提出基于贪心策略的多项式(GBP,greedy-based polynomial)时间近似算法,得到RSU的部署方案以解决覆盖问题。针... 详细信息

为了使用尽可能少的RSU实现对目标区域的有效覆盖,设计c街道模型,将对区域的覆盖转化为对区域内街道的覆盖,然后,在该模型下提出基于贪心策略的多项式(GBP,greedy-based polynomial)时间近似算法,得到RSU的部署方案以解决覆盖问题。针对城市中一些地形复杂的区域,设计Cue模型(complex urban environment model),将目标区域划分为子区域,然后提出基于shifting策略的多项式时间近似算法,并对算法的近似比率和时间复杂度进行了理论分析与证明。仿真结果表明,算法GBP能够有效地解决城市环境车联网中的区域覆盖问题。

关键词：车联网 RSU部署区域覆盖近似算法

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含有机质土-金属界面黏附特性与机制研究

岩土工程学报 2024年第3期46卷 605-615页

作者：朱俊宇裴利华桂跃昆明理工大学建筑工程学院云南昆明650500 中铁四院集团西南勘察设计有限公司云南昆明650504

土中有机质的存在对土-金属界面黏附有显著影响,但其影响规律及机制尚缺乏系统研究。通过在蒙脱石、伊利石和高岭土中添加泥炭,配置了不同矿质、有机质含量的黏性土样。利用MC-100型拉力试验机测试了不同含水率土-金属界面黏附力。试验... 详细信息

土中有机质的存在对土-金属界面黏附有显著影响,但其影响规律及机制尚缺乏系统研究。通过在蒙脱石、伊利石和高岭土中添加泥炭,配置了不同矿质、有机质含量的黏性土样。利用MC-100型拉力试验机测试了不同含水率土-金属界面黏附力。试验结果表明:在塑限至液限含水率范围内,黏附力F与含水率w的关系曲线为典型的“钟型”;有机质含量wu增大会导致F-w曲线由高陡变扁平;土样峰值黏附力Fmax随有机质含量wu变化可分为3个阶段:波动或缓慢下降(上升)阶段、急剧下降阶段和趋于稳定阶段。利用傅积平法测试了3种黏土矿物对有机质的饱和吸附量,从而明确了有机质在土中赋存形态随有机质含量变化的过程。机理分析表明:除了有机质含量外,有机质在土中的赋存形态对土样宏观黏附力也有显著影响。最后对分布于昆明地铁5号线沿线的天然泥炭土-金属界面黏附力进行了测试,得出其黏附力较小、黏附风险较小的结论,盾构机穿越泥炭土层没出现严重黏附刀盘或堵塞现象验证了该结论。

关键词：黏附力黏土矿物拉力试验稠度指数有机质含量

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大数据时代:网络安全与伦理问题

新媒体与社会 2014年第4期11卷 247-256页

作者：朱君玉厦门大学新闻传播学院

大数据应用是把双刃剑。一方面，它给人类社会带来了巨大的社会效益和经济效益；另一方面，它也给网络安全与伦理带来严重的威胁。本文试图从网络安全与伦理的角度出发，探讨大数据时代互联网数据利用面临的伦理问题。主要表现为：给个... 详细信息

大数据应用是把双刃剑。一方面，它给人类社会带来了巨大的社会效益和经济效益；另一方面，它也给网络安全与伦理带来严重的威胁。本文试图从网络安全与伦理的角度出发，探讨大数据时代互联网数据利用面临的伦理问题。主要表现为：给个人隐私带来极大威胁、加剧数据鸿沟和数据霸权现象、否定人的自由权利、促进娱乐主义和消费主义的进一步兴盛。

关键词：大数据隐私数据鸿沟信息安全伦理