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Measurement of ice flow velocities from GPS positions logged by short-period seismographs in East Antarctica

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Science China Earth Sciences 2021年第8期64卷 1381-1389页

作者： Lei fu Jingxue GUO Xiaofei chen Shenzhen Key Laboratory of Deep Offshore Oil and Gas Exploration Technology Southern University of Science and TechnologyShenzhen 518055China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory for Polar Science MNRPolar Research Institute of ChinaShanghai 200136China

The ice flow velocity is a basic feature of glaciers and ice sheets. Measuring ice flow velocities is very important for estimating the mass balance of ice sheets in the Arctic and Antarctic. Traditional methods for measuring ice flow velocity include the use of stakes, snow pits and on-site geodetic GPS and remote sensing measurement methods. Geodetic GPS measurements have high accuracy, but geodetic GPS monitoring points only sparsely cover the Antarctic ice sheets. Moreover, the resolution and accuracy of ice flow velocities based on remote sensing measurements are low. Although the accuracy of the location data recorded by the navigation-grade GPS receivers embedded in short-period seismographs is not as good as that of geodetic GPS,the ice flow velocity can be accurately measured by these navigation-grade GPS data collected over a sufficiently long period. In this paper, navigation-grade GPS location data obtained by passive seismic observations during the 36 th Chinese National Antarctic Research Expedition were used to accurately track the movement characteristics of the ice sheet in the Larsemann Hills of East Antarctica and the Taishan Station area. The results showed that the ice sheet in the two study areas is basically moving northwestward with an average ice flow velocity of approximately 1 m mon-1. The results in the Taishan Station area are basically consistent with the geodetic GPS results, indicating that it is feasible to use the embedded GPS location data from shortperiod seismographs to track the movement characteristics of ice sheets. The ice flow characteristics in the Larsemann Hills are more complex. The measured ice flow velocities in the Larsemann Hills with a resolution of 200 m help to understand its characteristics. In summary, the ice flow velocities derived from GPS location data are of great significance for studying ice sheet dynamics and glacier mass balance and for evaluating the systematic errors caused by ice sheet movements in s

关键词： Short-period seismograph Antarctic ice sheet Ice flow velocity GPS

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基于点云维度转换的双优化层手眼标定方法

组合机床与自动化加工技术 2025年第1期 185-189页

作者：陈琳付钰王龙友潘海鸿广西大学机械工程学院南宁530004

为提高点云相机与机器人坐标转换精度,提出一种双层Levenberg-Marquardt优化(D-LM)算法标定点云视觉系统和机器人的手眼关系。根据点云成像特点提出采用同心圆标记物代替棋盘格标定板,推导出2D-3D维度转换的标记物中心提取算法。利用欧... 详细信息

为提高点云相机与机器人坐标转换精度,提出一种双层Levenberg-Marquardt优化(D-LM)算法标定点云视觉系统和机器人的手眼关系。根据点云成像特点提出采用同心圆标记物代替棋盘格标定板,推导出2D-3D维度转换的标记物中心提取算法。利用欧拉角变换正交化手眼矩阵旋转矩阵。此外,构建双层LM优化模型对手眼矩阵进行优化。通过自主搭建的机器人平台验证提出的手眼标定算法,并与传统Tsai-LM标定方法对比。实验结果是采用提出的D-LM方法标定出的手眼矩阵平均误差为0.89 mm,优于Tsai-LM(平均误差3.55 mm),表明D-LM方法能减少系统随机误差对标定结果影响,提升工业领域视觉机器人工作精度。

关键词：点云处理手眼标定双层LM优化离群点检测

A bi-component polyoxometalate-derivative cathode material showed impressive electrochemical performance for the aqueous zinc-ion batteries

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Chinese Chemical Letters 2022年第8期33卷 3955-3960页

作者： Rui Huang Weiwei Wang Chi Zhang Peng He Yuyang Han nuo chen Jun Yan College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Hunan Provincial Key Laboratory of Chemical Power Sources Central South UniversityChangsha 410083China Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources Central South UniversityChangsha 410083China Hunan Provincial Key Laboratory of Micro&Nano Materials Interface Science Central South UniversityChangsha 410083China Changsha Changjun High School Changsha 410002China

Rechargeable aqueous zinc-ion batteries are recently gaining incremental attention because of low cost and material abundance,but their development is plagued by limited choices of cathode materials with satisfactory cycling *** polyoxometalates perform formidable redox stability and able to participate in multi-electron transfer,which was well-suited for energy ***,a bicomponent polyoxometalate-derivative KNiVO(K_(2)[Ni(H_(2)O)_(6)]_(2)[V_(10)O_(28)]·_(4)H_(2)O polyoxometalates after annealing)is firstly demonstrated as a cathode material for aqueous *** layered KV_(3)O_(8)(KVO)In the bi-component material constitutes Zn^(2+) migration and storage channels(K^(+) were substantially replaced by Zn^(2+) in the activation phase),and the three-dimensional NiV_(3)O_(8)(NiVO)part acts as skeleton to stabilize the ion channels,which assist the cell to demonstrate a high-rate capacity and specific energy of229.4 mAh/g and satisfactory cyclability(capacity retention of 99.1%after 4500 cycles at a current density of 4 A/g).These results prove the feasibility of POM as cathode materials precursor and put forward a novel pattern of the Zn^(2+)storage mechanism in the activated-KNiVO clusters,which also provide a new route for selecting or designing high-performance cathode for aqueous ZIBs and other advanced battery systems.

关键词： Cathode material Aqueous Zn-ion battery Bi-component material Polyoxometalate-derivative Cathodic activation

2D勒瓦娄哇石核的自动分类算法图像处理与应用

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计算机应用与软件 2025年第2期42卷 248-255页

作者：高雅陈哲扬付慧汪国平唐世华北京林业大学信息学院北京100083 南安普顿大学考古系英国南安普顿SO171BF 北京大学计算机学院北京100871 国防大学联合作战学院河北石家庄050084

考古学者对2D勒瓦娄哇石核剥片面进行目测分类具有主观性,不能产生标准的、一致的分类结果,故提出并实现一个可自动分类2D勒瓦娄哇石核的算法(2D Levallois Core Automatic Classification,LCAC2D)。计算机进行石核分类的难点在于,如何... 详细信息

考古学者对2D勒瓦娄哇石核剥片面进行目测分类具有主观性,不能产生标准的、一致的分类结果,故提出并实现一个可自动分类2D勒瓦娄哇石核的算法(2D Levallois Core Automatic Classification,LCAC2D)。计算机进行石核分类的难点在于,如何将勒瓦娄哇石核类型学分类理论转换为能够提取石核的可区分特征且可自动分类的算法程序。LCAC2D算法利用石核剥片面上的拓扑结构构建基于加权有向图的石核剥片面描述模型,进一步优化模型,对勒瓦娄哇石核进行自动或半自动的分类,在66个样本上测试,准确率达77%,结果表明LCAC2D算法首先实现了对2D勒瓦娄哇石核的定量分析。

关键词：勒瓦娄哇技术石核分类加权有向图

Research on new software compensation method of static and quasi-static errors for precision motion controller

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1938-1943页

作者： REN Kun fu Jian-zhong chen Zi-chen Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

To reduce mechanical vibrations induced by big errors compensation, a new software compensation method based on an improved digital differential analyzer (DDA) interpolator for static and quasi-static errors of machine tools is proposed. Based on principle of traditional DDA interpolator, a DDA interpolator is divided into command generator and command analyzer. There are three types of errors, considering the difference of positions between compensation points and interpolation segments. According to the classification, errors are distributed evenly in data processing and compensated to certain interpolation segments in machining. On-line implementation results show that the proposed approach greatly improves positioning accuracy of computer numerical control (CNC) machine tools.

关键词： Static and quasi-static errors Positioning and machining accuracy Digital differential analyzer (DDA) interoolator

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西北道地中药材种植及生产机械化概况

中国农机化学报 2025年第1期46卷 290-298页

作者：于庆旭欧阳安陈永生付菁菁陈晓王振伟农业农村部南京农业机械化研究所南京市210014 工业和信息化部装备工业发展中心北京市100846 中国农业科学院西部农业研究中心新疆昌吉831100

中药材种植业的发展,可保障人民安全使用中药。简述甘肃、陕西、新疆、宁夏、青海等西北五省区道地中药材种植概况,梳理促进中药材产业发展相关国家和当地政策,阐述西北道地中药材“直播育苗+移栽种植”种植模式和生产全程机械化概况。... 详细信息

中药材种植业的发展,可保障人民安全使用中药。简述甘肃、陕西、新疆、宁夏、青海等西北五省区道地中药材种植概况,梳理促进中药材产业发展相关国家和当地政策,阐述西北道地中药材“直播育苗+移栽种植”种植模式和生产全程机械化概况。针对中药材耕、种、管、收等关键环节机械化水平薄弱、亟需关键技术攻关与加强装备创新现状,分析西北道地中药材生产机械化面临的问题与挑战,包括种植土地碎片化严重、种植品类模式多样化、关键环节机械化较低、种植投入高且风险大和机具生产企业发展难等,从西北道地中药材种植面积规模化、种植模式标准化、主要品种关键作业环节优先突破、强化政策引导完善农业保险体系和推动西北地区企业增量高质发展等5个方面提出促进中药材生产机械化的建议,为我国中药材产业高质量发展提供借鉴。随着农业机械化、智能化水平的不断提升,以及中药材产业扶持政策实施,将逐步推进西北道地产区中药材全程机械化发展趋势,促进中药材特色产业发展和农民持续增收。

关键词：中药材产业西北道地产区中药材机械化政策扶持高质量发展

祁连山中部一次层状云降水云微物理特征的飞机观测研究

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干旱区研究 2025年第2期42卷 212-222页

作者：付双喜亓鹏常祎把黎陈祺甘肃省人工影响天气办公室甘肃兰州730000 中国气象局云降水物理与人工影响天气重点开放实验室北京100081

利用飞机探测数据,对2022年8月27日祁连山中部一次层状降水云系的微物理特征进行了分析。结果表明:不同高度层、不同区域的云微物理特征有明显差异。云中过冷水含量随高度升高而减少,在-6~-3℃层,平均过冷水含量为0.05 g·m^(-3),在-15~... 详细信息

利用飞机探测数据,对2022年8月27日祁连山中部一次层状降水云系的微物理特征进行了分析。结果表明:不同高度层、不同区域的云微物理特征有明显差异。云中过冷水含量随高度升高而减少,在-6~-3℃层,平均过冷水含量为0.05 g·m^(-3),在-15~-12℃的高层,过冷水含量仅为0.015 g·m^(-3),不到低层的1/3;凇附过程对各高度层粒子增长起重要作用,云中粒子平均直径可达几百微米,凇附和聚合过程共同作用,使粒子谱宽可达6 mm以上;-6~-3℃层粒子平均直径小于其上层粒子,这可能是大粒子下落蒸发、破碎造成的。在山脉西南侧,携带大量水汽的低层偏南气流遇地形抬升凝结、产生大量云滴,小粒子浓度比山脉东北侧高一个量级、过冷水含量也更高;山脉西南侧粒子以过冷云滴和霰粒子为主,聚合作用不明显、粒子数浓度更高;东北侧以聚合状冰粒子和霰粒子为主,小粒子浓度低导致粒子平均尺度更大。

关键词：云微物理特征飞机探测地形层状云祁连山

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福建省鳞毛蕨属植物新记录

福建农林大学学报（自然科学版） 2025年第1期54卷 84-88页

作者：付厚华韦宏金陈彬苏享修陈新艳陈世品福建农林大学林学院福建福州350002 上海辰山植物园/华东野生濒危资源植物保育中心上海201602 三明市园林中心福建三明365000

报道了福建省鳞毛蕨属植物分布新记录8种1变种,分别为中尼鳞毛蕨Dryopteris sinonepalensis ***&Fraser-Jenk.、裸叶鳞毛蕨***(Baker)***.、狭顶鳞毛蕨***(Thunb.)Kuntze、羽裂鳞毛蕨*** ***.、高鳞毛蕨***(***ô)***、密鳞高鳞毛蕨*** ***(***ô)***、两广鳞毛蕨*** Ching、边生鳞毛蕨*** ***.和寻乌鳞毛蕨*** Ching&***,并对寻乌鳞毛蕨及其相似种的形态学特征进行了描述。

关键词：华东地区福建鳞毛蕨科新记录

Multifunctional Ce-MOF@PdNPs with colorimetric fluorescent electrochemical activity for ultrasensitive and accurate detection of diethylstilbestrol

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Nano Research 2024年第11期17卷 9990-9998页

作者： Mingyue Ye Tingting Su Jin Li Xiaowan chen Dichen Ying Shijia Wu Zhouping Wang nuo Duan State Key Laboratory of Food Science and Resources Jiangnan University Wuxi 214122 China School of Food Science and Technology Jiangnan University Wuxi 214122 China International Joint Laboratory on Food Safety Jiangnan University Wuxi 214122 China

The development of biosensors is gaining tremendous attention in various fields due to their extraordinary advantages, however, their sensitivity and accuracy are still challenging. Herein, we proposed a novel multifunctional nanocomposite Ce-MOF@PdNPs (MOF = metal-organic framework, PdNPs = Pd nanoparticles)-mediated triple-readout aptasensor for accurate and reliable detection of diethylstilbestrol (DES), in which Ce-MOF@PdNPs exhibited excellent peroxidase (POD)-like activity, fluormetric, and electro conductive properties. In addition, enzymes-assisted target recycling amplification was utilized to improve the sensitivity, that is the specific binding of aptamer and DES triggered an Exo III enzyme-assisted recycling reaction. The generated F-DNA was captured by the H3 strand linked to Ce-MOF@PdNPs immobilized on the electrode, exposing cleavage sites and activating the *** enzyme-assisted recycling reaction, leading to the dissociation of Ce-MOF@PdNPs and a significant reduced electrochemical signal. The collected Ce-MOF@PdNPs solution also induced a proportional change in the color and fluorescence, achieving a colorimetric and fluormetric detection functionality. The detection limit under colorimetric mode was 0.16 and 0.76 ng/mL under fluorescence mode, and 0.87 pg/mL under electrochemical mode. This triple-readout aptasensor exhibits high sensitivity, selectivity and accuracy, providing a new idea for designing novel biosensing platforms for veterinary drug residue detection.

关键词： cerium-based materials Pd nanoparticles(PdNPs) aptamer colorimetric/fluorescence/electrochemical signal amplification