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Journal of Oceanology and Limnology 2024年第2期42卷 408-420页

作者： zhe chang Lina SUN Tengfei LIU Meng ZHANG Keda LIANG Junmin MENG Jing WANG School of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

Optical remote sensing has been widely used to study internal solitary waves(ISWs).Wind speed has an important effect on ISW imaging of optical remote *** light and dark bands of ISWs cannot be observed by optical remote sensing when the wind is too *** relationship between the characteristics of ISWs bands in optical remote sensing images and the wind speed is still *** influence of wind speeds on the characteristics of the ISWs bands is investigated based on the physical simulation experiments with the wind speeds of 1.6,3.1,3.5,3.8,and 3.9 m/*** experimental results show that when the wind speed is 3.9 m/s,the ISWs bands cannot be observed in optical remote sensing images with the stratification of h_(1)∶h_(2)=7∶58,ρ_(1)∶ρ_(2)=1∶*** the wind speeds are 3.1,3.5,and 3.8 m/s,which is lower than 3.9 m/s,the ISWs bands can be obtained in the simulated optical remote sensing *** location of the band’s dark and light extremum and the band’s peak-to-peak spacing are almost not affected by wind ***-significant wind speeds can cause a greater gray difference of the light-dark *** provided a scientific basis for further understanding of ISW optical remote sensing imaging.

关键词： internal solitary wave(ISW) optical remote sensing wind speed characteristics of ISWs bands

Experimental Study on the Variation of Optical Imaging Characteristics with Zenith Angle due to Internal Solitary Waves in Sunglint

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Journal of Ocean University of China 2024年第4期23卷 943-952页

作者： LIU Tengfei SUN Lina chang zhe ZHANG Meng LIANG Keda MENG Junmin WANG Jing School of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

Internal solitary waves(ISWs)change the roughness of the sea surface,thus producing dark and bright bands in optical ***,reasons for changes in imaging characteristics with the solar zenith angle remain *** this paper,the optical imaging pattern of ISWs in sunglint under different zenith angles of the light source is investigated by collecting optical images of ISWs through physical *** experiment involves setting 10 zenith angles of the light source,which are divided into area a the optical images of ISWs in the three areas show dark-bright mode,single bright band,and bright-dark mode,which are consistent with those observed by optical remote *** addition,this study analyzed the percentage of the dark and bright areas of the bands and the change in the relative gray difference and found changes in both areas under different zenith angles of the light *** MODIS and ASAR images display a similar brightness-darkness distance of the same ***,the relationship between the brightness-darkness distance and the characteristic half-width of ISWs is determined in accordance with the eKdV theory and the imaging mechanism of ISWs of the SAR ***,the relationship between them in the experiment is almost consistent with the theoretical result.

关键词： internal solitary waves optical imaging characteristic laboratory simulation zenith angle sunglint

Mammals of Gaoligong Mountain in China:Diversity,distribution,and conservation

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Zoological Research(Diversity and Conservation) 2024年第1期1卷 3-19页

作者： Quan Li Xue-You Li Wen-Qiang Hu Wen-Yu Song Shui-Wang He Hong-Jiao Wang zhe-chang Hu Meng-Cheng Li Kenneth Otieno Onditi Zhong-zheng Chen chang-zhe Pu Yun Xiong Cai-Hong Rao Fu-You Zhang chang-Sheng Zuo Xue-Long Jiang State Key Laboratory of Genetic Resources and Evolution&Yunnan Key Laboratory of Biodiversity and Ecological Conservation of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Gaoligong Mountain Forest Ecosystem Observation and Research Station of Yunnan Province&Dulongjiang Forest Ecosystem Research Station KunmingYunnan 650223China University of Chinese Academy of Sciences Beijing 101408China Vector Laboratory Institute of Pathogens and VectorsYunnan Provincial Key Laboratory for Zoonosis Control and PreventionDali UniversityDaliYunnan 671000China School of Ecology and Environment Anhui Normal UniversityWuhuAnhui 241002China Gongshan Administrative Sub-Bureau of Gaoligongshan National Nature Reserve NujiangYunnan 673500China Fugong Administrative Sub-Bureau of Gaoligongshan National Nature Reserve NujiangYunnan 673400China Baoshan Administrative Bureau of Gaoligongshan National Nature Reserve BaoshanYunnan 678000China Administrative Bureau of Tongbiguan Provincial Nature Reserve DehongYunnan 679300China

Gaoligong Mountain(hereafter,GLGM)is located at the intersection of Myanmar and China’s Yunnan Province and Xizang Zizhiqu,and spans three globally significant biodiversity hotspots:the Himalayas,Indo-Burma,and the Mountains of Southwest *** surveys of mammals in this ecologically important region have a long history,there is no comprehensive systematic checklist and distribution account of the mammals of ***,we compiled a mammal species checklist of GLGM based on thorough field investigations and literature *** also examined specimen collections and applied camera trapping surveys to explore the region’s mammal diversity and distribution *** recorded 212 mammal species in nine orders,33 families,and 119 genera,which accounts for 30.5%of China’s mammal species,and a high proportion of nationally protected(50)and globally threatened(29)*** species richness showed a symmetrical unimodal curve along the elevation gradient,peaking at intermediate elevations(2000 to 2500 m above sea level(asl)),and increasing generally from south to north,slightly higher in the east slope than in the *** analysis and non-metric multidimensional scaling revealed three distinct elevational assemblages(3500 m asl)and significant south-to-north variation,but no substantial differences between the east and west *** GLGM present a unique conservation value due to the high proportions of rare and endangered mammal species,complex faunal composition,high endemism,and being the distribution boundary for many *** study is an important phased account of mammal diversity in GLGM and makes a prospect for future research.

关键词： Biodiversity hotspot Eastern Himalaya Gaoligong Mountain Endemism Mammal conservation Hengduan Mountains

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基于分数阶S面模型的四旋翼轨迹跟踪控制

兵器装备工程学报 2024年第3期45卷 286-292页

作者：李佳成陈鹏云常哲中北大学航空宇航学院太原030000

四旋翼无人机具有欠驱动、非线性、强耦合的特点。针对四旋翼无人机轨迹跟踪控制中跟踪精度低,抗外界干扰能力弱的特点,通过对四旋翼无人机进行四元数建模,使用误差四元数作为控制器输入,消除了无人机在机动角度过大时的奇点问题,提出... 详细信息

四旋翼无人机具有欠驱动、非线性、强耦合的特点。针对四旋翼无人机轨迹跟踪控制中跟踪精度低,抗外界干扰能力弱的特点,通过对四旋翼无人机进行四元数建模,使用误差四元数作为控制器输入,消除了无人机在机动角度过大时的奇点问题,提出了一种分数阶S面的控制方法,即将分数阶PID控制与S面控制融合,作为一个新的控制器。轨迹跟踪试验表明,分数阶S面控制器在四旋翼无人机控制模型中的累计误差明显小于分数阶PID,证明了该方法具有抗风扰能力强、跟踪精度高的特点。

关键词：四旋翼无人机四元数分数阶PID S面控制轨迹跟踪

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高瓦斯矿井智能抽采管控系统的应用

陕西煤炭 2024年第1期43卷 124-127,140页

作者：李宝军常哲陕西黄陵二号煤矿有限公司陕西延安727307

针对矿井瓦斯抽采管道环境条件复杂、抽采计量设备性能要求高、瓦斯抽采达标评判智能化程度低等问题,开展抽采精准计量与抽采效果达标评价系统应用研究,分析了复杂管道环境适用的抽采检测技术与计量设备,构建了全过程、动态化的采掘工... 详细信息

针对矿井瓦斯抽采管道环境条件复杂、抽采计量设备性能要求高、瓦斯抽采达标评判智能化程度低等问题,开展抽采精准计量与抽采效果达标评价系统应用研究,分析了复杂管道环境适用的抽采检测技术与计量设备,构建了全过程、动态化的采掘工作面瓦斯抽采效果达标评判体系,黄陵二号煤矿通过在综采工作面现场应用分析,抽采监测设备满足精准计量要求,系统实现了可视化、动态化的抽采效果达标评价,极大地提升了瓦斯抽采精细化管理效率。

关键词：瓦斯抽采精准计量达标评价智能分析

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基于注意力机制的残差网络超分辨率重建方法

兵工自动化 2024年第4期43卷 40-45,67页

作者：常哲陈鹏云李佳成马英琪中北大学航空宇航学院太原030051 中北大学机电工程学院太原030051

针对现有方法在图像超分辨率重建中高频信息遗漏的问题,提出一种基于注意力机制的多层嵌套残差网络超分辨率重建方法,对不同的频次信息采用不同的特征提取方案。利用跨越残差网络结构将前端的特征信息利用恒等映射连接直接传送到后端的... 详细信息

针对现有方法在图像超分辨率重建中高频信息遗漏的问题,提出一种基于注意力机制的多层嵌套残差网络超分辨率重建方法,对不同的频次信息采用不同的特征提取方案。利用跨越残差网络结构将前端的特征信息利用恒等映射连接直接传送到后端的注意力机制模块,添加注意力机制的多层嵌套残差网络来捕捉原始图像中隐含的特征信息,通过深度并行残差网络结构融合图像特征信息。实验结果表明,改进后算法可有效提高图像超分辨率重建精度。

关键词：图像处理多层嵌套残差网络注意力机制超分辨率重建

Intensity correlation properties of x-ray beams split with Laue diffraction

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Chinese Physics B 2024年第1期33卷 379-383页

作者：赵昌哲司尚禹张海鹏薛莲李中亮肖体乔 Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Beam splitting is one of the main approaches to achieving x-ray ghost imaging, and the intensity correlation between diffraction beam and transmission beam will directly affect the imaging quality. In this paper, we investigate the intensity correlation between the split x-ray beams by Laue diffraction of stress-free crystal. The analysis based on the dynamical theory of x-ray diffraction indicates that the spatial resolution of diffraction image and transmission image are reduced due to the position shift of the exit beam. In the experimental setup, a stress-free crystal with a thickness of hundredmicrometers-level is used for beam splitting. The crystal is in a non-dispersive configuration equipped with a double-crystal monochromator to ensure that the dimension of the diffraction beam and transmission beam are consistent. A correlation coefficient of 0.92 is achieved experimentally and the high signal-to-noise ratio of the x-ray ghost imaging is *** of this paper demonstrate that the developed beam splitter of Laue crystal has the potential in the efficient data acquisition of x-ray ghost imaging.

关键词： x-ray ghost imaging beam splitting with Laue diffraction intensity correlation dynamical theory of x-ray diffraction

基于Super-Twisting滑模S面的无人机路径跟踪控制

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火力与指挥控制 2024年第2期49卷 11-17页

作者：张国兵石上瑶李佳成常哲陈鹏云中北大学航空宇航学院太原030051

针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控... 详细信息

针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控制。考虑到S面控制求导易导致积分爆炸的问题引入了二阶微分器,并对外界风组成进行建模研究。最后通过空间特殊曲线来验证所设计算法的控制性能。仿真结果表明,所设计的算法可以实现固定翼无人机对期望路径的精确跟踪,并具有良好的鲁棒性和抗干扰性能。

关键词：固定翼无人机 Super-Twisting滑模 S面控制风干扰

经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗儿童胆总管囊肿的效果观察

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罕少疾病杂志 2024年第8期31卷 78-79,85页

作者：常栋喆周良徐科耿宪杰郑州大学附属儿童医院、河南省儿童医院、郑州儿童医院普通外科河南郑州450000

目的探究经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗儿童胆总管囊肿的疗效。方法选取河南省儿童医院2012年8月至2022年8月收治的90例儿童胆总管囊肿患儿,使用随机数字法分为观察组(n=45)和对照组(n=45),观察组实施经脐单孔3D腔... 详细信息

目的探究经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗儿童胆总管囊肿的疗效。方法选取河南省儿童医院2012年8月至2022年8月收治的90例儿童胆总管囊肿患儿,使用随机数字法分为观察组(n=45)和对照组(n=45),观察组实施经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗,对照组行Roux-en-Y胆肠吻合术治疗,对比两组治疗有效率、手术相关指标、肝功能及术后并发症。结果观察组治疗有效率95.56%高于对照组82.22%(P<0.05);观察组手术时间、术中出血量、术后摄食时间及住院时间均低于对照组(P<0.05);观察组肝功能指标和术后并发症发生率均低于对照组(P<0.05)。结论针对儿童胆总管囊肿患儿,采用经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗具有良好的效果,在提升临床疗效,改善相关手术指标和肝功能指标,减少并发症等方面具有积极意义。

关键词：经脐单孔3D腔镜肝总管-空肠吻合改良Warren吻合术胆总管囊肿

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基于串级线性自抗扰的四旋翼姿态控制方法

遥测遥控 2024年第1期45卷 38-46页

作者：常哲陈鹏云李佳成石上瑶中北大学航空宇航学院太原030051 中北大学软件学院太原030051

针对四旋翼无人机姿态调整过程中,由于参数不确定性及外界环境干扰,往往给姿态控制带来一定困难。本文研究提出一种基于串级线性自抗扰的四旋翼姿态控制方法。首先建立四旋翼无人机的动力学姿态模型,提出采用串级PID双环路控制架构,将... 详细信息

针对四旋翼无人机姿态调整过程中,由于参数不确定性及外界环境干扰,往往给姿态控制带来一定困难。本文研究提出一种基于串级线性自抗扰的四旋翼姿态控制方法。首先建立四旋翼无人机的动力学姿态模型,提出采用串级PID双环路控制架构,将姿态控制任务分解为内外两个环路。采用Levant微分器提取控制参量,以强化跟踪能力。此外,对原线性自抗扰控制器进行优化,旨在更好地消除外界随机扰动对系统的影响。利用MATLAB Simulink环境对提出的控制方法进行模拟,结果表明相比传统方法,该方法能更好地抑制系统受扰动引起的影响,增强系统对期望信号的跟踪能力,从而明显提高了四旋翼无人机姿态调整的精度与稳定性,以及四旋翼无人机姿态控制的精度和鲁棒性。

关键词：四旋翼无人机线性自抗扰控制串级PID控制 Levant微分器