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Decoding the inconsistency of six cropland maps in china

The Crop Journal 2024年第1期12卷 281-294页

作者： Yifeng Cui Ronggao Liu Zhichao Li Chao Zhang Xiao-Peng Song jilin Yang Le Yu Mengxi Chen Jinwei Dong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China Department of Geographical Sciences University of MarylandCollege ParkMD 20740USA College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Beijing 100084China Tsinghua university(Department of Earth System Science)-Xi’an Institute of Surveying and Mapping Joint Research Center for Next-Generation Smart Mapping Beijing 100084China Institute of Remote Sensing and Geographic Information System Peking UniversityBeijing 100871China Department of Forest and Conservation Sciences University of British ColumbiaVancouverBCV6T 1Z4Canada

Accurate cropland information is critical for agricultural planning and production,especially in foodstressed countries like *** widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades,considerable discrepancies exist among these products both in total area and in spatial distribution of croplands,impeding further applications of these *** factors influencing their inconsistency are also *** this study,we evaluated the consistency and accuracy of six cropland maps widely used in china in circa 2.2.,including three state-of-the-art 10-m products(i.e.,Google Dynamic World,ESRI Land Cover,and ESA WorldCover)and three 30-m ones(i.e.,GLC_FCS30,GlobeLand 30,and CLCD).We also investigated the effects of landscape fragmentation,climate,and agricultural *** using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy(92.3%).These maps collectively overestimated Chinese cropland area by up to 56%.Up to 37%of the land showed spatial inconsistency among the maps,concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps,cropland fragmentation and management practices such as *** work shed light on the promotion of future cropland mapping efforts,especially in highly inconsistent regions.

关键词： Consistency and accuracy 10-and 30 m Cropland mapping Agricultural management china

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CSST Dense Star Field Preparation:A Framework for Astrometry and Photometry for Dense Star Field Images Obtained by the china Space Station Telescope(CSST)

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Research in Astronomy and Astrophysics 2024年第7期24卷 158-169页

作者： Yining Wang Rui Sun Tianyuan Deng Chenghui Zhao Peixuan Zhao Jiayi Yang Peng Jia Huigen Liu jilin Zhou College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Astronomy&Space Science Nanjing UniversityNanjing 210093China Peng Cheng Lab Shenzhen 518066China

The china Space Station Telescope(CSST)is a telescope with 2.m diameter,obtaining images with high quality through wide-field *** its first observation cycle,to capture time-domain observation data,the CSST is proposed to observe the Galactic halo across different *** data have significant potential for the study of properties of stars and ***,the density of stars in the Galactic center is high,and it is a well-known challenge to perform astrometry and photometry in such a dense star *** paper presents a deep learning-based framework designed to process dense star field images obtained by the CSST,which includes photometry,astrometry,and classifications of targets according to their light curve *** simulated CSST observation data,we demonstrate that this deep learning framework achieves photometry accuracy of 2.and astrometry accuracy of 0.03 pixel for stars with moderate brightness mag=2.(i band),surpassing results obtained by traditional ***,the deep learning based light curve classification algorithm could pick up celestial targets whose magnitude variations are 1.7 times larger than magnitude variations brought by Poisson photon *** anticipate that our framework could be effectively used to process dense star field images obtained by the CSST.

关键词： techniques photometric-methods data analysis-astrometry

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FINE STRUCTURE ANALYSIS OF DEFORMED STEEL 1Cr18Ni9

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Acta Metallurgica Sinica(English Letters) 1992年第4期5卷 266-268页

作者： TENG Feng’en WANG Yuming XU Yue jilin university,{2.,china jilin Univ Changchun China

X-ray diffraction profiles of various deformed steel 1Cr18Ni9 through stepped scanning were *** profile analysis,some structure parameters such as effective domain size D_(eff), dislocation density in domain,distribution parameterand bulk stored energy densiy (E/V),etc.,were *** results were compared with those of TEM *** true domain sizes D_e are comparable,but the minimum and characteristics of width of stack- ing fault are *** may be resulted from the large fluctuation in width of stacking fault.

关键词： austenitic stainless steel fine structure X-ray analysis

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Calorimetric Measurements of CuAlNi Alloys

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Journal of Materials Science & Technology 1995年第3期11卷 176-180页

作者： Qing JIANG(Dept. Metal Material Engineering, jilin university of Technology, {2., 13002., china) jilin Univ of Technology Changchun China

The martensitic transformation of CuAlNi single crystals is measured by DSC (differential scanning calorimeter). An isothermal single interface DO3-->2. transformation arises when the specimen is quenched at a slow rate, but 2.-->DO3 transformation always proceeds with multiple interfaces due to the existence of stored elastic energy inside martensite. The elastic energy is essentially stored on the martensitic interfaces and results in A(s)-->M(f), which brings a separate spectrum of heat flow on the measured curve. The size of stored elastic energy affects the hysteresis.

关键词： DO AQ Calorimetric Measurements of CuAlNi Alloys

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CHAOS FOR MIXING TRANSFORMATIONS

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Chinese Annals of Mathematics,Series B 1994年第4期15卷 501-506页

作者： LIAO GONGFU (Department of Mathematics,jilin university, {2. 13002., china.) jilin UNIV DEPT MATH CHANGCHUN 130023 PEOPLES R CHINA

For a class of mixing transformations of a compact metric space it is proved that each chaoticsubset is'small' but the possibility for any finite subset to display chaotic behavior is 'large'.

关键词： Compact metric space Chaotic subset Mixing transformation Topological mixing map.

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Effect of Metallurgical Behaviour at the Interface between Ceramic and Interlayer on the Si_3N_4/1.2.Cr-0.5Mo Steel Joint Strength

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Journal of Materials Science & Technology 1998年第1期14卷 20-24页

作者： Huaping XIONG (Dept. of Materials Science and Engineering, jilin university of Technology, {2. 13002., china) Dept. of Materials Science and Engineering Jilin University of Technology Changchun 130025 China

By using newly developed CuNi5~2.Ti16~2. B rapldly solidifled brazing filler the joining of Si3 N4/1.2.Cr-0.5Mo steel has been carried out with interlayer method. If employing the interlayer structure of steel (0.2.mm)/W (2.0 mm)/Ni(0.2.mm), the joint strength can be increased greatly compared with employing that of Ni/W/Ni, and the three point bend strength of the Joint shows the value of 2.1 MPa. The metallurgical behaviour at the interface between Si3N4 and the interlayer has been studied. It is found that Fe participated in the interfacial reactions between Si3N4 and the brazing filler at the Si3N4/steel (0.2.mm) interface and the compound Fe5Si3 was produced. However, since the reactions of Fe with the active Ti are weaker than those of Ni with Ti, the normal inter facial reactions were still assured at the interface of Si3N4/steel (0.2.mm) instead of Si3N4/Ni (0.2.mm), resulting in the improvement of the joint strength. The mechanism of the formation of Fe5Si3 is also discussed. Finally, some ideas to further ameliorate and simplify the interlayer structure are put forward.

关键词： Si Effect of Metallurgical Behaviour at the Interface between Ceramic and Interlayer on the Si3N4/1.2.Cr-0.5Mo Steel Joint Strength Ni Cr Mo

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The restricted EM algorithm under linear inequalities in a linear model with missing data

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Science china Mathematics 2005年第6期48卷 819-828页

作者： ZHENG Shurong, SHI Ningzhong & GUO Jianhua School of Mathematics and Statistics, Northeast Normal university, changchun 13002.,{2. Institute of Mathematics, jilin university, changchun 130012.{2. School of Mathematics and Statistics Northeast Normal University Changchun China Institute of Mathematics Jilin University Changchun China

This paper discusses the maximum likelihood estimate of β under linear inequalities A0β≥ a in a linear model with missing data, proposes the restricted EM algo rithm and proves the convergence.

关键词： EM algorithm, linear model, maximum likelihood estimate, missing data.

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Geochemistry and Genesis of the Sodium-Charnockitic Gneisses, Eastern Hebei Province, china

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 239-258页

作者： Wang Anjian changchun university of Earth Sciences, changchun, jilin changchun university of Earth Sciences Changchun Jilin

High in sodium and low in potassium (Na_2./ K_2.>1), the charnockitic gneiss series in theSantunying- Taipingzhai area, eastern Hebei province, consists of hypersthene- quartz- diorite,hypersthene-granodiorite and hypersthene-plagioclase-granite. Geological, petrological and large ion lithophileelement(LILE), high field strength element (HFSE) and REE geochemical studies suggest that themedium-coarse-grained hypersthene-granodiorite is the product of crystallization of anatectic magmas of thesame composition. Under granulite facies conditions, the equilibrium crystallization differentiation of themagmas yielded the early crystallization phase-high-SiO_2. LILE-depleted, low-∑REE, positive Eu anomalyand REE- saturated hypersthene- plagioclase- granite. The residual phase, coarse- grained to pegmatitichypersthene- granodiorite, is marked by low SiO_2. LILE-enrichment, high ∑REE and *** rocks and hypersthene-quartz-diorite enclaves constitute the sodium-charnockitic gneiss series in easternHebei province. Model calculation for trace elements in the granitoids was applied. On the basis of a systematicgeological study, the equation for calculation was chosen, the source magma was determined and the partitioncoefficients were obtained. The resulting curves are entirely consistent with those observed in the patterns of ac-tual rocks. The study indicates that whole-rock REE patterns can not be used directly in the comparison of thesources and genesis of granitoids.

关键词： sodium-charnockitic gneisses geochemistry genesis eastern Hebei province

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SiO_2.AS HETEROGENEOUS NUCLEI OF INTERGROWTH EUTECTIC IN MODIFIED AS-CAST MEDIUM MANGANESE STEEL

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 156-160页

作者： JIANG Qichuan YAN Jiulin GUAN Qingfeng WANG Shoushi RONG Fujie LI Zhang jilin university of Technology,{2.,china 13002.,china associate professor,jilin university of Technology,{2. jilin Univ Changchun China

By calculation of thermodynamics,analysis of crystal structure and study of TEM and eletron probe,it is first discovered that SiO2.can be acted as one of the heterogeneous nu- clei for lamellar intergorowth eutectic(a... 详细信息

关键词： SiO_2 heterogeneous necleus intergrowth eutectic medium manganese steel

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Modal extension rule

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Progress in Natural Science:Materials International 2005年第6期15卷 550-558页

作者： WU Xia*, SUN Jigui, LIN Hai and FENG Shasha(College of Computer Science and Technology, jilin university, {2. 130012. china Key Laboratory for Symbolic Computation and Knowledge Engineering, jilin university, {2. 130012. china) College of Computer Science and Technology Jilin University Changchun 130012 China Key Lab. for Symbolic Comp. and Knowledge Eng. Jilin University Changchun 130012 China

Modal logics are good candidates for a formal theory of agents. The efficiency of reasoning method in modal logics is very important, because it determines whether or not the reasoning method can be widely used in systems based on agent. In this paper, we modify the extension rule theorem proving method we presented before, and then apply it to P-logic that is translated from modal logic by functional transformation. At last, we give the proof of its soundness and completeness.

关键词： theorem proving extension rule modal logics functional transformation.

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