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单帧红外弱小目标检测技术研究现状与展望

信号处理 2024年第5期40卷 887-906页

作者：杨德贵韩同欢胡亮白正阳中南大学自动化学院湖南长沙410083 光电智能测控湖南省重点实验室湖南长沙410083

红外探测技术具有探测距离远、抗干扰能力强、隐蔽性强和全天候等优势在天基预警、末敏弹制导等领域得到了广泛应用。通过红外成像技术能够得到目标图像从而对目标进行预警、识别和跟踪。在实际场景中,目标图像往往所占像素比例小,信号... 详细信息

红外探测技术具有探测距离远、抗干扰能力强、隐蔽性强和全天候等优势在天基预警、末敏弹制导等领域得到了广泛应用。通过红外成像技术能够得到目标图像从而对目标进行预警、识别和跟踪。在实际场景中,目标图像往往所占像素比例小,信号强度低,容易湮没在背景图像中;背景图像变化剧烈,存在较强的结构信息、边缘和噪声,红外图像信噪比低,目标检测难度较大,一直是目标检测领域的研究难点和热门话题。为提高红外图像弱小目标检测能力,大量的弱小目标检测算法被提出。现有的主流的检测手段根据图像数据检测方式分为单帧检测和多帧检测两大类,多帧算法依赖大量的图像数据支撑,响应周期长,应用潜力低,而单帧检测算法凭借复杂度低、时效性强、便于硬件实现等特点,被广泛应用在高速运动目标检测、预警等领域。因此本文以单帧红外弱小目标检测算法为主体,从技术方向入手,着重阐述了基于滤波、基于对比度与显著性分析、基于数据优化和深度学习四类单帧弱小目标检测算法的原理与近年来的典型应用,通过仿真试验和算法复杂度对比了不同算法的性能、优势和不足,总结了弱小目标检测算法的研究现状并对本领域的发展趋势进行了展望。本文的工作能帮助读者快速了解本领域的研究现状,为研究人员提供参考。

关键词：红外检测单帧滤波算法视觉显著性数据优化

纳米Sn/SnO_2/石墨复合材料作为锂离子电池负极材料的研究

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化工时刊 2008年第6期22卷 1-3页

作者：杨同欢周学酬李求忠刘永梅福州大学化学化工学院福建福州350108

以氯化锡、氨水和无水乙醇为原料,采用溶胶-凝胶法制备纳米SnO2粉末,并与石墨、葡萄糖共热制备Sn/SnO2/石墨复合材料。用X射线衍射分析、透射电镜和电化学测试对材料进行了表征。采用该方法制备出的Sn/SnO2/石墨复合材料可逆容量可达680... 详细信息

以氯化锡、氨水和无水乙醇为原料,采用溶胶-凝胶法制备纳米SnO2粉末,并与石墨、葡萄糖共热制备Sn/SnO2/石墨复合材料。用X射线衍射分析、透射电镜和电化学测试对材料进行了表征。采用该方法制备出的Sn/SnO2/石墨复合材料可逆容量可达680 mA.h.g-1,经过20次循环后容量基本稳定在380 mA.h.g-1。

关键词：锂离子电池负极 SnO2 石墨复合

Improvement and Application of Grain Size Distribution Characteristics Calculation of Bed Material

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四川大学学报（工程科学版） 2005年第S1期37卷 148-153页

作者： Wang, Xianye Wang, Xiekang Liu, tonghuan Lab. of Hydraulics and Mountain River Eng. Sichuan Univ. Chengdu 610065 China

Grain size distribution of bed material is an important characteristic for studying evolution of natural river channel by means of experimental ways and numerical modeling of flow and sediment *** this study,the fractal characteristic of sediment particle has been defined by means of fractal theory based on ana- lyzing the property of grain size distribution of bed material in the river ***,the fractal prop- erty of sediment particle has been applied to judge the process of armorin...

关键词： grain size distribution bed material sediment particle

基于示踪气体释放和计算流体力学模拟的事故后矿井通风状况预测

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制冷与空调（四川） 2024年第1期38卷 112-118,147页

作者：朱振锋刘同欢石军安陕西华彬煤业股份有限公司蒋家河煤矿咸阳713509 上海煤科信息科技有限公司上海200030

在地下矿井发生意外事件后,快速确定矿井内部通风状态对于矿工和救援队伍做出有效决策至关重要。开发了一种将示踪气体和计算流体力学模型相结合的方法,用以在事故后预测矿井通风系统内部的流场。实验在一个实际的地下矿井中进行,使用SF... 详细信息

在地下矿井发生意外事件后,快速确定矿井内部通风状态对于矿工和救援队伍做出有效决策至关重要。开发了一种将示踪气体和计算流体力学模型相结合的方法,用以在事故后预测矿井通风系统内部的流场。实验在一个实际的地下矿井中进行,使用SF6气体作为示踪气体分别测试了事故中最容易出现的四种通风状态下矿井巷道中的示踪气体分布,同时使用CFD对混合效应和扩散效应复杂的关键区域进行了精确预测。研究发现,模拟与实验的误差在大约在10%以内,加压风机的开关对巷道中的示踪气体分布几乎没有影响,而停止门的开启可以使得巷道中的示踪气体浓度下降2000ppb左右。因此在实际运行中因尽量采取措施确保停止门在事故后的开启。这项工作为事故后远程识别通风系统损坏的程度提供了参考。

关键词：矿井通风系统示踪气体计算流体力学流场模拟

Salt freezing resistance improvement of cement-based materials incorporated with calcined layered double hydroxide

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第3期10卷 427-440页

作者： Jinyang Huo tonghuan Zhang Zhenjun Wang Xiaofeng Wang Xin Ji Pei Wang School of Materials Science and Engineering Chang'an UniversityXi'an 710064China Engineering Research Center of Transportation Materials of Ministry of Education Chang'an UniversityXi'an 710064China Henan Communications Planning&Design Institute Co. Ltd.Zhengzhou 450052China

Salt freezing damage has severe impacts on durability of cement-based materials(CBMs).Calcined layered double hydroxide(CLDH),as an efficient environmental-friendly adsorption material,can impart excellent salt freezing resistance to *** this work,salt freezing resistance improvement of CBMs incorporated with CLDH was experimentally evaluated by chloride binding capacity,mass loss rate,relative dynamic elastic modulus,setting time,compressive strength,and micro structure *** these,the salt freezing damage model was established to effectively express the quantitative relationship between influencing factors and evaluation indexes of the salt freezing resistance of *** show that CLDH can reconstruct its original layered structure to form reconstructed layered double hydroxide(RLDH).RLDH combines with chloride ions to form RLDH-Cl recrystallization,which can improve chloride binding capacity and pore structures of CBMs to relieve the salt freezing *** salt freezing damage model indicates that the suitable CLDH content can evidently alleviate the salt freezing damage,which facilitates the quantitative analysis of the effect of CLDH on the salt freezing resistance of CBMs.

关键词： Cement-based materials Calcined layered double hydroxide Salt freezing resistance Micro structure Salt freezing damage

Crystal Structure and Hydrogen Storage Behaviors of Mg/MoS2 Composites from Ball Milling

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Journal of Wuhan University of Technology(Materials Science) 2016年第4期31卷 773-778页

作者：韩宗盈周仕学 WANG Naifei ZHANG Qianqian ZHANG tonghuan RAN Weixian College of Chemical and Environmental Engineering Shandong University of Science and Technology Qingdao 266590 China School of Chemical and Environmental Engineering China University of Mining and Technology Beijing 100083 China

The Mg/MoS2 composites were prepared by ball milling under argon atmosphere,and the effect of MoS2 on the crystal structure and hydrogen storage properties of Mg was *** is found that 10 wt% of MoS2 is sufficient to prevent particle aggregation and cold welding during the milling *** crystallite size of Mg will remain constant at slightly less than 38.8 nm with the milling process due to the size confinement effect of *** dehydrogenation temperature of MgH2 is reduced to 390.4-429.4 ℃ due to the crystallite size *** fitting by Johnson-Mehl-Avrami model,it is found that Mg crystal grows by three dimension controlled by interface transformation during the process of MgH2 ***2 has a weak catalyst effect on the decomposition of MgH2 and activation energy of 148.9 k J/mol is needed for the dehydrogenation process calculated by the Arrhenius equation.

关键词： crystallite milling confinement aggregation fitting argon agglomeration magnesium subsequent hydrogenation

Model-Free Sliding Mode Control for PMSM Drive System Based on Ultra-Local Model

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Energy Engineering 2022年第2期119卷 767-780页

作者： Kaihui Zhao Wenchang Liu tonghuan Yin Ruirui Zhou Wangke Dai Gang Huang College of Electrical and Information Engineering Hunan University of TechnologyZhuzhou412007China School of Engineering Tokyo University of TechnologyHachioji192-0982Japan Institute of Refrigeration Technology Gree Electric AppliancesInc.of ZhuhaiZhuhai519070China School of Traffic and Transportation Engineering Central South UniversityChangsha410073China College of Railway Transportation Hunan University of TechnologyZhuzhou412007China

This paper presents a novel model-free sliding mode control(MFSMC)method to improve the speed response of permanent magnet synchronous machine(PMSM)drive *** ultra-local model(ULM)is first derived based on the input and the output of the ***,the novel MFSMC method is presented,and the controller is designed based on ULM and MFSMC.A sliding mode observer(SMO)is constructed to estimate the unknown part of the *** estimated unknown part is feedbacked to MFSMC controller to performcompensation for parameter perturbations and external *** with the sliding mode control(SMC)method,the results of simulation and experiment demonstrate that the presented MFSMC method improves the dynamic response and robustness of the PMSM drive system.

关键词： Permanent magnet synchronous motor(PMSM) ultra-local model(ULM) model-free sliding mode control(MFSMC) sliding mode observer(SMO)

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高层建筑消防安全隐患及对策分析

武汉理工大学学报（信息与管理工程版） 2024年第1期46卷 35-40,52页

作者：熊慧萍杨梓淳陈万红陈倩雯吴童欢张英武汉市建设工程设计审查和消防验收中心湖北武汉430015 武汉理工大学安全科学与应急管理学院湖北武汉430070 武汉市消防救援支队湖北武汉430024 中国标准化研究院北京100088 湖北烽火平安智能消防科技有限公司湖北武汉430014

随着我国城市化进程的加速,高层建筑数量不断增加,具有安全隐患多、火灾蔓延快、灭火困难等特点。如果发生火灾,极易造成巨大的财产损失和人员伤亡。从火灾发生、发展、灭火和救援4个方面总结了高层建筑的火灾特点,基于事故“4M”要素... 详细信息

随着我国城市化进程的加速,高层建筑数量不断增加,具有安全隐患多、火灾蔓延快、灭火困难等特点。如果发生火灾,极易造成巨大的财产损失和人员伤亡。从火灾发生、发展、灭火和救援4个方面总结了高层建筑的火灾特点,基于事故“4M”要素理论将高层建筑存在的消防安全隐患分为内部人员隐患、硬件设施隐患和安全管理隐患,并根据上述隐患进行分析,提出了提高高层建筑内部人员消防安全意识、严格执行高层建筑消防防火设计标准规范、明确消防安全管理责任主体、严格实施高层建筑消防日常监督管理和审核验收、构建基于物联网的高层建筑消防安全管理一体化平台等对策,从而提升消防安全管理的信息化水平。

关键词：高层建筑消防安全火灾特点安全隐患安全对策

Stability of selenium and its speciation analysis in water using automatic system separation and HR-ICP-MS measurement

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Chinese Chemical Letters 2022年第7期33卷 3444-3450页

作者： Junqiang yang Yawen Chen Keliang Shi Kesheng Hu Run Li Xiaoqing Gao Qian Wang Weibo Zhang Yun Zhou Yanyun Wang Jiangang He tonghuan Liu Xiaolin Hou Frontier Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Beijing National Laboratory for Molecular Sciences Fundamental Science Laboratory on Radiochemistry&Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou 730000China CNNC Lanzhou Uranium Enrichment Co. Ltd.Lanzhou 730000China Environmental Monitor Center of Gansu Province Lanzhou 730000China

A simple and convenient method has been developed for the pre-concentration and separation of inorganic selenium species from environmental water samples using anion exchange chromatographic column combined with high resolution inductively coupled plasma mass spectrometry(HR-ICP-MS)measurement.^(75)Se(Ⅳ) and ^(75)Se(Ⅵ)were prepared and used as tracers during the *** volatility of selenium during solution evaporation was investigated to establish a reliable water samples pretreatment *** parameters which affect the uptake of Se(Ⅳ)and Se(Ⅵ)on Dowex1×8 resin was optimized and the procedure for Se(Ⅳ)and Se(Ⅵ)separation was *** Se(Ⅳ)and Se(Ⅵ)are retained on the column in natural or alkaline solution with high distribution *** successive gradient elution of pre-concentrated species of selenium with HNO_(3)solution allows to differentiate between ***(Ⅳ)and Se(Ⅵ)finally were eluted with 0.05 mol/L HNO_(3) and 5.0 mol/L HNO_(3),*** proposed method has been successfully verified using the certified reference materials(CRMs)of real water samples,and spiked recoveries for real samples were 98%-104%with 5%relative standard deviations(RSDs).The developed procedure is proved to be reliable and can be used for the rapid determination of selenium species in environmental water samples.

关键词： Inorganic selenium Speciation Automatic system separation Rapid determination Water sample