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Road traffic and geography topology based opportunistic routing for VANETs

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 32-39页

作者： DING yu LIU Ya-zhi GONG xiang-yang WANG Wen-dong State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications College of Information Hebei United University

The message delivery .ratio and transmission delay is affected deeply by road traffic flow in vehicular ad hoc networks （VANETs）. An opportunistic routing based on geography and road traffic flow for VANETs （ORRIS） was proposed. ORRIS leverages the knowledge of geography positions, motion vectors and road traffic flows. In order to estimate the traffic flow density, the history of encounter number of the vehicles in the opposite direction is considered in ORRIS. The forwarding decisions are made by distributed vehicles based on the geography topology and the road traffic flow. The real map based simulation results show that ORRIS has a better performance than other algorithms, especially when the road traffic is busy or the traffic flow rates have great differences between roads.

关键词： VANETs traffic flow opportunistic routing geography topology

同方期刊数据库

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在役大跨径桥梁基于远程监测的可靠性评价

重庆交通大学学报（自然科学版） 2007年第4期26卷 32-35页

作者：周建庭向毓志郝袆沈小俊周志祥蒋震董志清李红镝周勇谭隆友重庆交通大学重庆400074 西藏交通厅公路勘察规划设计院西藏拉萨850000 重庆市交通委员会重庆400017 重庆市公路交通委员会交通基本建设工程质量监督站重庆400067 重庆市丰都县公路质检站重庆400082 重庆市公路实力开发有限公司重庆451147

结合实际桥梁,在介绍大跨径斜拉桥监测方案的基础上,重点阐述了基于可靠性理论的大跨径斜拉桥远程监测评价体系,包括荷载效应参数的获取、桥梁结构抗力参数的获取以及动态可靠度的计算方法等.可望在实践中起到一定的借鉴作用.

关键词：远程监测评价可靠性

铸牢中华民族共同体意识研究回溯与展望(2017—2023)——基于CiteSpace的可视化分析

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三峡大学学报（人文社会科学版） 2025年第1期47卷 29-40,56页

作者：龚志祥谭雯心东北大学秦皇岛分校民族学学院河北秦皇岛066004

本文运用CiteSpace软件绘制可视化知识图谱,分析2017—2023年中国知网CNKI核心期刊(北大核心、CSSCI期刊)铸牢中华民族共同体意识研究领域的1 772篇高质量文献,从发文量及趋势、作者及机构、引用量及高频关键词、多学科跨学科及研究机... 详细信息

本文运用CiteSpace软件绘制可视化知识图谱,分析2017—2023年中国知网CNKI核心期刊(北大核心、CSSCI期刊)铸牢中华民族共同体意识研究领域的1 772篇高质量文献,从发文量及趋势、作者及机构、引用量及高频关键词、多学科跨学科及研究机构合作等进行分析。铸牢中华民族共同体意识研究的发文量自2017年始逐年增长,经过快速上升,达到高水平的平稳增长。铸牢中华民族共同体意识理论体系研究深化仍是热点,实践研究与政策响应研究需进一步拓展和深化。

关键词：铸牢中华民族共同体意识 CiteSpace可视化分析研究现状

利用联合诊断技术对设备SF_6气体分析的应用

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广西电力 2013年第5期36卷 50-53,59页

作者：刘陈瑶朱立平黄云光余志祥广西电网公司电力科学研究院南宁520023

联合气相色谱、红外光谱2种分析手段,检测设备中SF6分解物,可发现设备异常运行状态。该联合诊断技术能实现14种SF6分解物的定性、定量检测,同时两种检测方法数据之间能实现相互验证和比对,为判断设备状态提供了可靠、准确的依据。利用... 详细信息

联合气相色谱、红外光谱2种分析手段,检测设备中SF6分解物,可发现设备异常运行状态。该联合诊断技术能实现14种SF6分解物的定性、定量检测,同时两种检测方法数据之间能实现相互验证和比对,为判断设备状态提供了可靠、准确的依据。利用该诊断技术对运行的SF6电气设备状态进行诊断,发现2台设备SF6分解物组分与含量异常,由此判断设备异常,设备解体检查结果验证了诊断的正确性。

关键词： SF6气体组分分析气相色谱红外光谱绝缘故障

EFFECT OF SWEEP AND EJECTION EVENTS ON PARTICLE DISPERSION IN WALL BOUNDED TURBULENT FLOWS

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Journal of Hydrodynamics 2012年第5期24卷 794-799页

作者： LUO Jian-ping LU zhi-ming QIU xiang LI Dong-mei LIU yu-lu School of Mechanical Engineering Shanghai Institute of Technology Shanghai 200235 China Shanghai Key Laboratory of Mechanics in Energy Engineering and Shanghai Institute of Applied Mathematicsand Mechanics Shanghai University Shanghai 200072 China School of Science Shanghai Institute of Technology Shanghai 200235 China Shanghai Institute of Technology Shanghai 200235 China

This paper studies the sweep and ejection events in a channel flow with Reτ = 80 by using Direct Numerical Simulation （DNS）. The effects of ejection and sweep events on the transport of fluid particles are analyzed separately through a quadrant technique. By analyzing trajectories of the particles released at different wall-normal locations, it is found that the particles from the ejection events mainly move upward while the particles from the sweep events move downward of the flow during short and intermediate diffusion time durations. Numerical results show that the effects of the ejection and sweep events on the mean displacement and the mean square dispersion remain for a long time, one-order of magnitude larger than the streamwise Lagrangian integral ~cales.

关键词： sweep ejection dispersion quadrant analysis turbulent channel flow

Anti-Insect Activity of the Methanol Extracts of Fern and Gymnosperm

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Agricultural Sciences in China 2010年第2期9卷 249-256页

作者： HUANG Su-qing ZHANG zhi-xiang LI You-zhi LI yu-xia XU Han-hong Key Laboratory of Natural Pesticide ＆ Chemical Biology Ministry of Education/South China Agricultural University Guangzhou 510642 P.R. China College of Bio-Safety Science and Technology Hunan Agricultural University Changsha 410128 P.R.China

With environmental and food safety issues becoming one of the greatest concerns of the public, active plant compounds play more and more important roles in pest controlling. Fern to their particular status in plant taxology and co-evolution are of great significance for application as new pesticides due with insects. In this study, methanol extracts were distilled from wild fern and gymnosperm of 54 species of 22 families collected from Shiwandashan Mountain in Guangxi Zhuang Autonomous Region of China. Insecticidal activities of the methanol extracts were assayed on both adult house fly （Musca domestica） and mosquito （Aedes albopictus）. Significant insecticidal activities were exhibited in the methanol extracts of five species, Cupressusfunebris （leaves and stems）, Cycas acuminatissima （roots）, Keteleeria fortunei （leaves and stems）, Onychium japonicum （whole plant）, and Pinus taiwanensis var. Darning shanensis （leaves and stems）. Applications of the extracts of these plants resulted in higher than 50% mortalities in 4th instar larvae of A. albopictus at 24 h after treatment. The methanol extracts from 13 species possessed insecticidal activities against the adult of M. domestica at 48 h after treatment with higher than 90% mortalities. The extensive screening results showed that these fern and gymnosperm were highly potential to be botanical insecticides. The findings provide a feasible and valuable basis for further investigation.

关键词： plant extracts anti-insect activity Musca domestica Aedes albopictus

Discussion on position of China’s north-south transitional zone by comparative analysis of mountain altitudinal belts

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Journal of Mountain Science 2020年第8期17卷 1901-1915页

作者： KOU zhi-xiang YAO Yong-hui HU yu-fan ZHANG Bai-ping State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The Qinling Mountains has always been regarded as an essential dividing line between the warm temperate zone and the subtropical zone in eastern China and plays a vital role in the geoecological pattern of ***,there is controversy about the specific location of this geographical boundary in the academic *** a product of the combined effects of zonal and non-zonal factors,the mountain altitudinal belts(MABs)can reflect both the horizontal zonality and the vertical zonality of vegetation *** the MAB information,we can not only profoundly understand the complex mountain system of QinlingDaba Mountains but can also judge its nature as a geographical boundary more ***,based on the comparative analysis of basal belt,dominant belt characteristics and belt structure characteristics of the MABs in Qinling-Daba Mountains,subtropical and temperate mountains,this paper analyzed the MAB differences and similarities among Qinling-Daba Mountains,subtropical and temperate typical mountains,to reveal the vegetation distribution characteristics in the north-south transitional *** results show that:(1)The MABs of the southern part of QinlingDaba Mountains(southern slope of the Daba Mountains)are the same or similar to those of the Subtropical Mountains,and the MABs of the northern part of Qinling-Daba Mountains(northern slope of the Qinling Mountains)are similar to those of the temperate *** it shows obvious transitional characteristics in the vast area between the northern slope of the Daba Mountains and the southern slope of the Qinling Mountains:the basal belts gradually transit from the evergreen broadleaved forest belt(basal belt in subtropical mountains)to the evergreen and deciduous broad-leaved mixed forest belt,and the dominant belts also transit from the evergreen broad-leaved forest belt to the evergreen and deciduous broad-leaved mixed forest belt or the deciduous broad-leaved forest belt.(2)The transi

关键词： Qinling-Daba Mountains Mountain altitudinal belt(MAB) North-south transitional zone Subtropical zone Warm temperate zone Vegetation

Side Chain Engineering of Sulfonated Poly(arylene ether)s for Proton Exchange Membranes

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Chinese Journal of Polymer Science 2020年第6期38卷 644-652页

作者： xiang Zhang zhi-Wen Li Xia-Lin Chen Dong-Yang Chen yu-Ying Zheng College of Materials Science and Engineering Fuzhou UniversityFuzhou 3501116China PowerChina Railway Construction Co. LtdBeijing 100037China

Proton conductivity of proton exchange membranes(PEMs)strongly relies on microscopic morphology,which can be modulated by engineering the distribution of ionic ***,poly(arylene ether)s with densely distributed allyl functionalities are polymerized from a tetra-allyl bisphenol A *** subsequent thiol-ene addition with sodium 3-mercapto-1-propanesulfonate yields comb-shaped sulfonated fluorinated poly(arylene ether)s(SFPAEs)with ion exchange capacities(lECs)ranging from 1.29 mmol·g^-1 to 1.78 mmol g^-*** SFPAEs exhibit superior proton conductivity over the whole temperature range,which is attributed to the enhanced hydrophilic/hydrophobic phase separation as evidenced by small angle X-ray scattering *** SFPAE-4-40 with an IEC of 1.78 mmol·g^-1 shows the largest proton conductivity of 93 mS-crrr1 at room temperature under fully hydrated condition,higher than that of Nafion ***,the vanadium redox flow battery(VRFB)assembled with SFPAE-4-40 separator exhibits higher energy efficiency than the VRFB assembled with Nafion 212.

关键词： Proton exchange membrane Thiol-ene addition Side-chain engineering Phase separation Vanadium redox flow battery

TURBULENT MIXING AND EVOLUTION IN A STABLY STRATIFIED FLOW WITH A TEMPERATURE STEP

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Journal of Hydrodynamics 2009年第1期21卷 84-92页

作者： QIU xiang ZHANG Dao-xiang LU zhi-ming LIU yu-lu Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Mathematics Shanghai University Shanghai 200444 China

Large-Eddy Simulation （LES） is applied to examine the turbulent mixing and evolution in a stably stratified flow with a thermally sharp interface. Turbulent velocity intensities and turbulent kinetic energy are analyzed by considering the mean shear and stratification effects. The evolution of turbulent mixing layer and turbulent structures are mainly investigated. The results show that the streamwise intensities are much larger than the vertical intensities, and vertical fluctuations decay more rapidly at the presence of stratification. The qualitatively computational results suggest that the mixing layer, defined by the mean temperature, inclines to the side with small inlet velocity. The evolution of the half-width of the mixing layer shows two different slopes. The turbulent structure with high vorticity is restricted in the mixing layer especially in strong stratified cases.

关键词： stratified turbulence turbulent mixing turbulent structure Large-Eddy Simulation (LES)