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Evolving patterns of agricultural production space in China:A network-based approach

地理学与可持续性（英文） 2024年第1期5卷 121-134页

作者： Shuhui Yang Zhongkai Li Jianlin Zhou Yancheng Gao xuefeng cui School of Systems Science Beijing Normal UniversityBeijing 100875China Leibniz Institute for Agricultural Development in Transition Economies(IAMO) Halle(Saale)06120Germany State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Systems Science Beijing Normal UniversityBeijing 100875China

The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food *** studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological *** this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in *** results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past *** little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively ***,identified provincial communities closely resemble China's agricultural natural ***,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural *** the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special *** findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development.

关键词： Agricultural system Complex network Agricultural production space Proximity matrix Production capability

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新疆生态区的生态系统服务的时空变化特征分析

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气候与环境研究 2024年第3期29卷 302-316页

作者：杨舒慧崔雪锋中国气象局沈阳大气环境研究所沈阳110166 北京师范大学系统科学学院北京100875 莱布尼茨转型经济体农业发展研究所哈雷(萨尔)德国06120

基于土地覆被与分类数据、气象数据、流域数据、土壤数据、数字高程模型(Digital Elevation Model,DEM)、归一化植被指数(Normalized Difference Vegetation Index,NDVI)等数据,利用生态系统服务评估与权衡模型(Integrated Valuable of Ecosystem Services and Tradeoffs Model,InVEST)和改进风蚀方程(Revised Wind Erosion Equation,RWEQ),评估了1992~2018年新疆各生态区的生态系统服务的时空变化及各生态区的服务簇变化。结果表明:1)1992~2018年新疆生境支持服务和碳储存与封存服务能力显著提高,其中在阿尔泰山—准噶尔西部山地森林草原生态区、天山山地森林与草原生态区和帕米尔—昆仑山—阿尔金山高寒草原生态区最为显著。2)土壤保持服务和防风固沙服务以2007年为界呈现分段特征。1992~2007年土壤保持服务和防风固沙服务能力下降,而2007~2018年两种服务能力都呈上升趋势,总体呈现改善趋势。3)以生态区为单位,每个生态区的核心生态系统服务不同。1992~2018年各服务簇整体服务能力提高。区域生态系统服务评估是厘清生态系统复杂性的关键,本研究可为推进新疆乃至干旱区的生态规划、生态修复与保护,提高生态系统服务能力的重要参考。

关键词：生态系统服务生态功能区 InVEST模型改进风蚀方程模型固碳

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环件轧机大型斜辊轴断裂的在线焊接修复

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焊接技术 2024年第3期53卷 133-136,140页

作者：范兴海方革新崔学峰杨西安徽马钢设备检修有限公司安徽马鞍山243000 马钢轨道交通材料科技有限公司安徽马鞍山243000

针对大型斜辊轴断裂问题,实施在线焊接修复,文中首先对斜辊轴基体42CrMo及其焊接材料的焊接性能及进行了分析,并对焊接工装进行了说明,着重介绍了通过手工钨极氩弧焊(TIG)和焊条电弧焊(SMAW)组合操作法进行断裂斜辊轴现场焊接的工艺流... 详细信息

针对大型斜辊轴断裂问题,实施在线焊接修复,文中首先对斜辊轴基体42CrMo及其焊接材料的焊接性能及进行了分析,并对焊接工装进行了说明,着重介绍了通过手工钨极氩弧焊(TIG)和焊条电弧焊(SMAW)组合操作法进行断裂斜辊轴现场焊接的工艺流程。结果表明,采用上述方法成功完成了断裂斜辊轴连体焊缝,通过基体-过渡层-表面合金耐磨层焊接处理后完全满足了使用要求。

关键词：斜辊轴组对工装组合操作焊接工艺

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Pedotransfer functions for predicting bulk density of coastal soils in East China

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Pedosphere 2023年第6期33卷 849-856页

作者： Guanghui ZHENG Caixia JIAO Xianli XIE xuefeng cui Gang SHANG Chengyi ZHAO Rong ZENG School of Geographic Sciences Nanjing University of Information Science&TechnologyNanjing 210044China Meteorology and Climate Centre School of Mathematics and StatisticsUniversity College DublinBelfieldDublin 4Ireland Institute of Soil Science Chinese Academy of ScienceNanjing 210008China School of Systems Science Beijing Normal UniversityBeijing 100875China

Soil bulk density(BD) is an important physical property and an essential factor for weight-to-volume conversion. However, BD is often missing from soil databases because its direct measurement is labor-intensive, time-consuming, and sometimes impractical, particularly on a large scale. Therefore, pedotransfer functions(PTFs) have been developed over several decades to predict BD. Here, six previously revised PTFs(including five basic functions and stepwise multiple linear regression(SMLR)) and two new PTFs, partial least squares regression(PLSR) and support vector machine regression(SVMR), were used to develop BD-predicting PTFs for coastal soils in East China. Predictor variables included soil organic carbon(SOC) and particle size distribution(PSD). To compare the robustness and reliability of the PTFs used, the calibration and prediction processes were performed 1 000 times using the calibration and validation sets divided by a random sampling algorithm. The results showed that SOC was the most important predictor, and the revised PTFs performed reasonably although only SOC was included. The PSD data were useful for a better prediction of BD, and sand and clay fractions were the second and third most important properties for predicting BD. Compared to the other PTFs, the PLSR was shown to be slightly better for the study area(the average adjusted coefficient of determination for prediction was 0.581). These results suggest that PLSR with SOC and PSD data can be used to fill in the missing BD data in coastal soil databases and provide important information to estimate coastal carbon storage, which will further improve our understanding of sea-land interactions under the conditions of ongoing global warming.

关键词： partial least squares regression particle size distribution soil organic carbon stepwise multiple linear regression support vector machine regression

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Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1322-1332页

作者： Qinghe cui xuefeng Liu Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik Jr. Dzmitry Bahrets Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Technical Acoustics National Academy of SciencesVitebsk 210009Belarus

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the *** technology has a very broad application prospect in industrial *** have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this *** this review,metals were classified according to their crystal *** effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were *** main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

关键词： ultrasonic vibration plastic forming crystal structure microstructure forming mechanism

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Impact of Drought on Agriculture in the Indo-Gangetic Plain,India

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Advances in Atmospheric Sciences 2017年第3期34卷 335-346页

作者： Reshmita NATH Debashis NATH Qian LI Wen CHEN xuefeng cui Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of System Sciences Beijing Normal UniversityBeijing 100875China Key Laboratory of Middle Atmosphere and Global Environmental Observations Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Meteorology and Climate Unit School of Mathematical ScienceUniversity College DublinDublin 4Ireland

In this study, we investigate the spatiotemporal characteristics of drought in India and its impact on agriculture during the summer season （April-September）. In the analysis, we use Standardized Precipitation Evapotranspiration Index （SPEI） datasets between 1982 and 2012 at the six-monthly timescale. Based on the criterion SPEI 〈 -1, we obtain a map of the number of occurrences of drought and find that the humid subtropical Upper Middle Gangetic Plain （UMGP） region is highly drought-prone, with an occurrence frequency of 40%-45%. This UMGP region contributes at least 18%-20% of India＇s annual cereal production. Not only the probability of drought, but the UMGP region has become increasingly drought-prone in recent decades. Moreover, cereal production in the UMGP region has experienced a gradual declining trend from 2000 onwards, which is consistent with the increase in drought-affected areas from 20%-25% to 50%-60%, before and after 2000, respectively. A higher correlation coefficient （-0.69） between the cereal production changes and drought-affected areas confirms that at least 50% of the agricultural （cereal） losses are associated with drought. While analyzing the individual impact of precipitation and surface temperature on SPEI at 6 month timescale [SPEI （6）] we find that, in the UMGP region, surface temperature plays the primary role in the lowering of the SPEI. The linkage is further confirmed by correlation analysis between SPEI （6） and surface temperature, which exhibits strong negative values in the UMGP region. Higher temperatures may have caused more evaporation and drying, which therefore increased the area affected by drought in recent decades.

关键词： drought agriculture SPEI Indo-Gangetic Plain temperature precipitation potential evapotranspiration

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Integrating global socio-economic influences into a regional land use change model for China

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Frontiers of Earth Science 2014年第1期8卷 81-92页

作者： Xia XU Qiong GAO Changhui PENG xuefeng cui Yinghui LIU Li JIANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Department of Biology Sciences institute of environment Science University of Quebec at Montreal Montreal H3C 3P8 Canada College of Global Change and Earth System Research Beijing Normal University Beijing 100875 China Academy of Resource Beijing Normal University Beijing 100875 China Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

With rapid economic development and urba- nization, land use in China has experienced huge changes in recent years; and this will probably continue in the future. Land use problems in China are urgent and need further study. Rapid land-use change and economic development make China an ideal region for integrated land use change studies, particularly the examination of multiple factors and global-regional interactions in the context of global economic integration. This paper presents an integrated modeling approach to examine the impact of global socio-economic processes on land use changes at a regional scale. We develop an integrated model system by coupling a simple global socio-economic model （GLOBFOOD） and regional spatial allocation model （CLUE）. The model system is illustrated with an application to land use in China. For a given climate change, population growth, and various socio-economic situations, a global socio-economic model simulates the impact of global market and economy on land use, and quantifies changes of different land use types. The land use spatial distribution model decides the type of land use most appropriate in each spatial grid by employing a weighted suitability index, derived from expert knowledge abot^t the ecosystem state and site conditions. A series of model simulations will be conducted and analyzed to demonstrate the ability of the integrated model to link global socio- economic factors with regional land use changes in China. The results allow an exploration of the future dynamics of land use and landscapes in China.

关键词： global socio-economic influence land use change model integrating China

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Direct anastomosis of contralateral C_7 nerve root transfer with affected-side inferior trunk for repair of brachial plexus avulsion injury

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Neural Regeneration Research 2006年第6期1卷 566-568页

作者： Houjun Yan Changqing Hu Yingli Jia Chunjie cui xuefeng Li Jingyang Zhang Department of Hand Surgery the 252 Hospital of Chinese PLA Baoding 071000 Hebei Province China

AIM： To observe the effect of direct anastomosis of contralateral C7 nerve root transferred through prespina route with affected-side infedor trunk for repair of brachial plexus avulsion injury, and investigate its feasibility. METHODS ： Two male patients, with the age of 24 and 41 years respectively, were retrieved. When admitted to the hospital, they were diagnosed as brachial plexus avulsion injury. They subjected the operation in the 252 Hospital of Chinese PLA in March 2006 and May 2006 respectively. The proximal end of contralateral C7 nerve root was dissociated to nerve root pore and the distal end was dissociated to anterior and posterior divisions of middle trunk. The injured C7 nerve root was widely dissociated to inferior trunk, medial cord, ulnar nerve and medial head of median nerve. When elbow and shoulder joints were in flexion, the injured C7 nerve root was directly anastomosed with contralateral C7 nerve root in the gap between affected-side cervical vagina vasorum and esophagus with no tensions. RESULTS： During 3 to 5 hours of operation, little hemorrhage was found, nerves were not used for connection. Dyspnea, hoarse voice and other complications did not appear, either. In the postoperative 7^th to 8^th months, electromyogram examination showed that the growth velocity of anastomosed nerve was normal. CONCLUSION ： Direct anastomosis of contralateral C7 nerve root transferred through prespinal route with affected-side inferior trunk can be used for repair of brachial plexus avulsion injury with satisfying therapeutic effects.

关键词： brachial plexus nerve root therapeutic effects median nerve velocity of the growth

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中国肉类供需模型研究综述及研究建议

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北京师范大学学报（自然科学版） 2022年第6期58卷 838-843页

作者：贾俊文崔雪锋北京师范大学系统科学学院北京师范大学地表过程与资源生态国家重点实验室北京100875

经过对现有供需模型效果与肉类供需问题的分析,发现不能忽略地区间的差异;机器学习方法是肉类供需研究方面更可靠的工具;肉类的消费、生产、贸易和政府政策举措时刻处在动态平衡的状态,应在考虑地区差异性的基础上,分别针对消费、生产... 详细信息

经过对现有供需模型效果与肉类供需问题的分析,发现不能忽略地区间的差异;机器学习方法是肉类供需研究方面更可靠的工具;肉类的消费、生产、贸易和政府政策举措时刻处在动态平衡的状态,应在考虑地区差异性的基础上,分别针对消费、生产、贸易、政策模块进行历史研究和未来预估,运用多主体思想模拟各模块之间的平衡互动关系.

关键词：肉类供需模型时间序列演化归因复杂系统机器学习

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A Dynamic Fuzzy Description Logic

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Wuhan University Journal of Natural Sciences 2008年第4期13卷 417-420页

作者： FANG Wei XIAN xuefeng ZHAO Pengpeng cui Zhiming Jiangsu Provincial Key Laboratory of Computer InformationProcessing Technology Soochow University Suzhou 215006Jiangsu China

Fuzzy description logics are considered as the logical infrastructure of fuzzy knowledge representation on the semantic Web. To deal with fuzzy and dynamic knowledge on the semantic Web and its applications, a new fuzzy extension of Attribute Language with Complement based on dynamic fuzzy logic called the dynamic fuzzy description logic （DFALC） is presented. The syntax and semantics of DFALC are formally defined, and the forms of axioms and assertions are specified. The DFALC provides more reasonable logic foundation for the semantic Web, and overcomes the insufficiency of using fuzzy description logic FALC to act as logical foundation for the semantic Web. The extended DFALC is more expressive than the existing fuzzy description logics and present more fuzzy information on the semantic Web.

关键词： dynamic fuzzy logic description logic dynamic fuzzy description logic semantic Web

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