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Automatic extraction of lunar impact craters from Chang'E-1 satellite photographs

Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 162-169页

作者： WAN Cong CHENG WeiMing zhou zengpo ZHAO ShangMin XIA Yao State Key Laboratory of Resources and Environmental Information Systems Institute of Geographic and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

The distribution characteristics of the impact craters can provide a large amount of information on impact history and the lunar evolution process. In this research, based on the digital elevation model （DEM） data originating from Change＇E-1 CCD stereo camera, three automatic extraction methods for the impact craters are implemented in two research areas： direct extraction from flooded DEM data （the Flooded method）, object-oriented extraction from DEM data by using ENVI ZOOM function （the Object-Oriented method） and novel object-oriented extraction from flooded DEM data （the Flooded Object-Oriented method）. Accuracy assessment, extracted degree computation, cumulative frequency analysis, shape and age analysis of the extracted craters combined display the following results. （1） The Flooded Object-Oriented method yields better accuracy than the other two methods in the two research areas; the extraction result of the Flooded method offers the similar accuracy to that of the Object-Oriented method. （2） The cumulative frequency curves for the extracted craters and the confirmed craters share a simi- lar change trajectory. （3） The number of the impact craters extracted by the three methods in the Imbrian period is the largest and is of various types; as to their age earlier than lmbrain, it is difficult to extract because they could have been destroyed.

关键词： automatic extraction lunar impact craters Object-Oriented method accuracy assessment cumulative frequencyanalysis Chang'E-1 data

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Research and compilation of the Geomorphologic Atlas of the People＇s Republic of China （1：1,000,000）

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Journal of Geographical Sciences 2011年第1期21卷 89-100页

作者： CHENG Weiming zhou Chenghu CHAI Huixia ZHAO Shangmin LIU Haijiang zhou zengpo Institute of Geographic Sciences and Natural Resources Research CAS State Key Laboratory of Resources and Environmental Information Systems Beijing 100101 China Xinjiang Institute of Ecology and Geography CAS Urumqi 830011 China China National Environmental Monitoring Center Beijing 100012 China

Geomorphologic maps are one of the most fundamental materials of the natural environment. They have been widely used in scientific research,resource exploration and extraction,education and military affairs etc. An editorial committee was established in 2001 to collect materials for researching and compiling a set of new 1：1,000,000 geomorphologic atlas of China. A digital geomorphologic database was created with visual interpretation from Landsat TM/ETM imageries and SRTM-DEM etc. The atlas compiled from the database was finished. The main characteristics of the atlas are as follows：Firstly,Landsat TM/ETM imageries,published geomorphologic maps or sketches,geographical base maps,digital geological maps,and other thematic maps were collected,which were uniformly geometrically rectified,clipped into uniform sheets,and stored in the foundation database. Secondly,based on the legends of 15 sheets 1：1,000,000 maps published in the 1980s,a geomorphologic classification system was built by combining morphology and genesis types. The system comprised seven hierarchical layers：basic morphology,genesis,sub-genesis,morphology,micro-morphology,slope and aspect,material composition and lithology. These layers were stored in the database during visual image interpretation. About 2000 kinds of morpho-genesis and 300 kinds of morpho-structure were interpreted. Thirdly,the legend system was built,which included color,symbol bases and note bases etc.,compilation standards and procedures were developed,74 sheets of 1：1,000,000 covering all land and sea territories of China were compiled,the 1：1,000,000 geomorphologic atlas of the People＇s Republic of China was finished and published. The atlas will fill the blanks in national basic scale thematic maps,and the geomorphologic database could be applied widely in many fields in the future.

关键词： digital geomorphology geomorphologic map 1:1,000,000 geomorphologic database

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月球正面撞击坑的空间分布特征分析

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地球信息科学学报 2012年第5期14卷 618-626页

作者：周增坡程维明万丛侯琳中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 中国科学院大学北京100049 东北师范大学城市与环境科学学院长春130024

通过IAU最新公布的撞击坑名录、"嫦娥一号"影像与DEM数据,本文使用数理统计和空间分析的方法研究了月球正面撞击坑分布的空间不均衡性。主要体现在:(1)月球正面直径较大的撞击坑主要分布在月陆区域,且集中趋势明显,而月海区域直径较大... 详细信息

通过IAU最新公布的撞击坑名录、"嫦娥一号"影像与DEM数据,本文使用数理统计和空间分析的方法研究了月球正面撞击坑分布的空间不均衡性。主要体现在:(1)月球正面直径较大的撞击坑主要分布在月陆区域,且集中趋势明显,而月海区域直径较大的撞击坑分布较少,周围有大量直径较小的撞击坑;(2)直径较大的撞击坑在月表具有一定随机性,而直径较小的撞击坑在月表的集中性明显;(3)赤道区域的撞击坑密度小于两极区域,前导半球的撞击坑数量小于后随半球;月海区域的撞击坑密度小于月陆区域;密度最大的区域位于月球正面的中南部;(4)月球正面深度大于2.5km的撞击坑主要集中在月陆区域,且在南极的中央经线附近更为集中;在57°N至24°S之间,深径比处于较高水平,最大值出现在14°N附近,均值在0.14左右波动,自该区域至南北两极,深径比逐渐减小,并在南极附近出现最小值;(5)月陆区域撞击坑坡度最大值的均值大于月海区域;坡度最大值的均值规律性明显,即自赤道至两极,撞击坑坡度最大值的均值逐渐增大。月球撞击坑的空间分布具有一定空间集聚性、经向和纬向差异性,该特征与撞击坑形成理论间的耦合关系仍需深入研究。

关键词：月球正面不均衡性撞击坑嫦娥一号

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基于DEM的火山口地貌识别方法探讨

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地球信息科学 2009年第6期11卷 773-777页

作者：周增坡程维明周成虎张洪岩中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 中国科学院研究生院北京100049 东北师范大学城市与环境科学学院长春130024

本文以吉林省靖宇县西南部的龙湾火山群为例,进行了火山口地貌图像识别方法探讨。在提取过程中,根据研究区内火山口均位于熔岩台地上的特点:首先,将研究区划分为平原和山地等地貌类型;然后,将生成的坡度数据与DEM高程数据相乘,实现对DE... 详细信息

本文以吉林省靖宇县西南部的龙湾火山群为例,进行了火山口地貌图像识别方法探讨。在提取过程中,根据研究区内火山口均位于熔岩台地上的特点:首先,将研究区划分为平原和山地等地貌类型;然后,将生成的坡度数据与DEM高程数据相乘,实现对DEM数据按照地形高低起伏的加权,以突显火山口在高程数据上的表现。根据火山口"中间低,四周高"的形态特点及在DEM上的表现,建立了火山口识别模板,对火山口进行识别。最后,参照研究区内的遥感影像,对提取的结果进行验证和修改。

关键词：数字地貌火山口提取自动/半自动

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Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期68卷 96-117页

作者： Jianhong Liu Qiang zhou Yuxiao Lin Xinsheng Zhao Guangmin zhou Xiaoxiao Li School of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed.

关键词： supercapacitor wide-temperature electrode design active materials

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Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-Lei zhou Siwei Wang Yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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Fine-tuning the spatial allocation of phytohormones for smart canopy, smart breeding, and smart agriculture

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Science China Life Sciences 2025年第1期68卷 309-310页

作者： Tao zhou Lin Li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University HuBei HongShan Laboratory

The dual challenges of global climate change and population growth have increased demand for higher crop yields per unit area. The innovative technology of smart agriculture aims to synergize breeding, cultivation, and production through the application of biological and informatics technologies. Historically, the “Green Revolution” introduced semidwarf varieties of certain key crops by utilizing mutations affecting gibberellin pathways, which significantly increased planting densities and yields.

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Microstructure and Wear/corrosion Resistance of Stainless Steel Laser-alloyed with Mn+W_(2)C, Mn+NiWC and Mn+SiC

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 283-294页

作者： zhou Rui DIAO Xiaogang SUN Yixin School of Metallurgical Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China CITIC Heavy Cast Iron Industry Co. Ltd.Luoyang 417039China

In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed *** evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were *** indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+*** as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C *** improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.

关键词： laser surface alloying stainless steel carbide type microstructure wear and corrosion resistance

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Distributed fiber optic sensing system for vibration monitoring of 3D printed bridges

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Optoelectronics Letters 2025年第1期21卷 28-34页

作者： ZHAO Shuai zhou Ran LUO Mingming LIU Jianfei LIU Xiongfei zhou Tao School of Electronic Information Engineering Hebei University of Technology Tianjin Key Laboratory of Electronic Materials and Devices School of Civil Engineering and Transportation Hebei University of Technology Tianjin Jinhang Institute of Technical Physics

The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities, including design, construction, and maintenance of bridges, tunnels, ports and other infrastructures. In this paper, a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment, covering a vibration frequency from 5 Hz to 25 kHz. The sensing fiber was arranged as an S type layout on the bridge to recognize the standing state, windblown disturbance, and walking vibration. Moreover, the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences, respectively. The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge, which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.

关键词： Spinning (fibers)

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Controlled cationic ring-opening polymerization of L-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian Wang Zijing zhou Bin Wang Yuesheng Li Tianjin Key Laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich polylactide

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