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Attitude Control of Multiple Rigid Bodies with Uncertainties and Disturbances

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 2-10页

作者： Yuanqing Xia Ning Zhou kunfeng Lu Yong Li the School of Automation Key Laboratory of Intelligent Control and Decision of Complex SystemsBeijing Institute of Technology the Qian Xuesen Laboratory of Space Technology China Academy of Space Technology

Decentralized attitude synchronization and tracking control for multiple rigid bodies are investigated in this paper. In the presence of inertia uncertainties and environmental disturbances, we propose a class of decentralized adaptive sliding mode control laws. An adaptive control strategy is adopted to reject the uncertainties and disturbances. Using the Lyapunov approach and graph theory, it is shown that the control laws can guarantee a group of rigid bodies to track the desired time-varying attitude and angular velocity while maintaining attitude synchronization with other rigid bodies in the formation. Simulation examples are provided to illustrate the feasibility and advantage of the control algorithm. © 2014 Chinese Association of Automation.

关键词： Adaptive control systems Algorithms Attitude control Environmental regulations Graph theory Rigid structures Sliding mode control Synchronization

The Formation of the Jiaodong Gold Province

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1801-1820页

作者： DENG Jun wang Qingfei LIU Xuefei ZHANG Liang YANG Liqiang YANG Lin QIU kunfeng GUO Linnan LIANG Yayun MA Yao State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Chengdu Center China Geological SurveyChengdu 610081China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

Gold deposits in Jiaodong,termed Jiaodong-type,are tectonically located in the southeastern margin of the North China *** major features are reviewed in this paper to highlight the differences between Jiaodong deposits and other genetic types of gold *** mineralization was synchronized with asthenosphere upwelling indicated by synore OIB-like mafic dike and large-scale crustal thinning suggested by decrease of Sr/Y from pre-ore to syn-ore *** upwelling induced by the roll-back of Paleo-Pacific Plate drove partial melting of lithospheric mantle and devolatilization,which induced the release of the ore-forming *** concomitant with magmatic records,mineralization migrated from the western Jiaobei terrane(133–127 Ma)to the eastern Sulu orogenic belt(114–108 Ma),corresponding to the eastward roll-back of Paleo-Pacific *** mineralization in Jiaodong formed in the transitions of ductile to brittle deformation,rapid to slow crustal uplift,and regional compression to *** the regional-scale,the gold deposits in the Jiaobei terrane are mostly situated at intersections between NE-trending faults and EW-trending basement faults,and gold orebodies dominantly controlled by the lithologic contacts between Precambrian metamorphic rocks and Mesozoic *** mineralization was dominated by the disseminated-veinlet ores related to quartz–sericite alteration in strong cataclasite-breccia zone,with subsidiary thick quartz-sulfide veins developed in secondary fault *** ore-forming fluids belong to a H_(2)O–CO_(2)–NaCl±CH_(4)system and show minor variations in salinity among different types of ***-fluid feedback involving fluid-rock reaction and hydrofracturing triggered the fluid phase separation and resultant gold *** Jiaodong gold deposits are distinct from orogenic and intrusion-related gold deposits in terms of tectonic setting,origin of ore-forming fluids,and mechanism of gold deposition.

关键词： Jiaodong-type geodynamic trigger ore-controlling structure ore-forming fluids structure-fluid feedback mineralization model

Network Sorting Algorithm of Multi-Frequency Signal with Adaptive SNR

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Journal of Beijing Institute of Technology 2018年第2期27卷 206-212页

作者： Xinyong Yu Ying Guo kunfeng Zhang Lei Li Hongguang Li Institute of Information and Navigation Air Force Engineering UniversityXi'an 710077China Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory Shijiazhuang 050081China

An signal noise ratio（ SNR） adaptive sorting algorithm using the time-frequency（ TF）sparsity of frequency-hopping（ FH） signal is proposed in this paper. Firstly,the Gabor transformation is used as TF transformation in the system and a sorting model is established under undetermined condition; then the SNR adaptive pivot threshold setting method is used to find the TF single source. The mixed matrix is estimated according to the TF matrix of single source. Lastly,signal sorting is realized through improved subspace projection combined with relative power deviation of source. Theoretical analysis and simulation results showthat this algorithm has good effectiveness and performance.

关键词： frequency-hopping(FH) under-determined adaptive signal noise ratio(SNR) time-frequency(TF) signal source network sorting

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海上低渗透油田油井低效原因分析及解堵措施

当代化工 2024年第5期53卷 1182-1187页

作者：李立冬林科雄罗刚任坤峰中海油服上海分公司上海200335 荆州市汉科新技术研究所湖北荆州434000

为了找出海上X油田油井低产低效的原因,并进一步提高海上低渗透油田的开发效率,在分析了目标油田基本概况以及开发现状的基础上,通过室内实验对目标油田油井损害原因进行的分析,并研制了一套新型复合解堵体系。结果表明:水锁伤害、入井... 详细信息

为了找出海上X油田油井低产低效的原因,并进一步提高海上低渗透油田的开发效率,在分析了目标油田基本概况以及开发现状的基础上,通过室内实验对目标油田油井损害原因进行的分析,并研制了一套新型复合解堵体系。结果表明:水锁伤害、入井流体伤害、有机质沉积伤害以及注入水和地层水不配伍导致的结垢伤害是造成海上X油田油井低效的主要原因。新型复合解堵体系主要由有机解堵液、无机解堵液和顶替液组成,有机解堵液对有机垢的溶解效果较好,无机解堵液对现场无机堵塞物的溶蚀能力较强,并且缓蚀性能较好。复合解堵体系对污染后的岩心具有良好的解堵效果,解堵后岩心的渗透率恢复值均能达到97%以上。现场应用结果表明,A1井采取复合解堵体系施工后解堵效果显著,日增油达到了60 m^(3)以上,措施有效期较长,施工效果较好。

关键词：海上低渗透油田低产低效储层伤害复合解堵体系解堵效果黏度渗透率

西双版纳热带森林土壤有机碳积累-分配动态对蚂蚁筑巢活动的响应

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生态环境学报 2024年第1期33卷 35-44页

作者：王郑钧王邵军肖博解玲玲郭志鹏张昆凤张路路樊宇翔郭晓飞罗双夏佳慧李瑞杨胜秋兰梦杰西南林业大学生态与环境学院云南昆明650224

蚂蚁筑巢能够通过影响土壤微生物及理化环境而直接或间接调控土壤有机碳各组分积累及分配动态。以西双版纳崖豆藤热带森林群落为研究样地,测定蚁巢和非巢地土壤碳库组分(总有机碳、易氧化有机碳、微生物生物量碳)含量及分配(易氧化有机... 详细信息

蚂蚁筑巢能够通过影响土壤微生物及理化环境而直接或间接调控土壤有机碳各组分积累及分配动态。以西双版纳崖豆藤热带森林群落为研究样地,测定蚁巢和非巢地土壤碳库组分(总有机碳、易氧化有机碳、微生物生物量碳)含量及分配(易氧化有机碳/总有机碳、微生物生物量碳/总有机碳)的时空动态,分析蚂蚁筑巢引起热带森林土壤性质改变对有机碳组分积累与分配的影响特征。结果表明,1)蚂蚁筑巢显著促进土壤总有机碳及各组分含量的积累(P<0.01)。相较于非巢地,蚁巢土壤总有机碳、微生物生物量碳、易氧化有机碳含量分别提高了19.7%、35.4%和153.3%。2)蚂蚁筑巢显著影响土壤碳库各组分含量的时空变化(P<0.050)。其中,相较于非蚁巢,蚁巢土壤总有机碳、易氧化有机碳、微生物生物量碳含量季节变化的增幅分别为11.4%-30.1%、13.6%-72.3%、53.4%-212.2%;蚁巢土壤总有机碳、微生物生物量碳、易氧化有机碳含量沿土层降幅(43.1%-422.4%)显著高于非蚁巢(38.1%-111.4%)。3)蚁巢土壤微生物生物量碳(15.2%)和易氧化有机碳(36.9%)在总有机碳中分配均值均显著高于非巢地(7.5%-31.6%),蚁巢土壤微生物生物量碳分配沿土层降幅(63.1%)小于非蚁巢(75.2%),易氧化有机碳分配(277.2%)则大于非蚁巢(53.4%)。4)主成分分析表明,温湿度、pH、氨氮是调控蚁巢土壤有机碳组分积累的主要协同因子,温度和容重是蚁巢土壤有机碳组分分配的主控因子。蚂蚁筑巢主要通过改变土壤物理环境(微气候、酸碱性、通气性)和土壤氮库(铵氮)的状况,进而对土壤有机碳组分积累及组分分配产生重要影响。

关键词：蚂蚁筑巢活性碳组分碳积累碳分配西双版纳热带森林

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阿联酋高等教育在地国际化研究

世界教育信息 2024年第5期37卷 17-25页

作者：李小红陈坤凤童锦花吕峡广西大学公共管理学院南宁530004 广西大学国际学院南宁530004

高等教育在地国际化是全球化时代各国培养国际人才的创新性实践模式。处于经济转型期的阿联酋,为满足大量外籍人员接受高等教育的需求、促进高等教育机会性别平等、打造技术劳动力型区域教育枢纽,积极推进高等教育在地国际化。阿联酋通... 详细信息

高等教育在地国际化是全球化时代各国培养国际人才的创新性实践模式。处于经济转型期的阿联酋,为满足大量外籍人员接受高等教育的需求、促进高等教育机会性别平等、打造技术劳动力型区域教育枢纽,积极推进高等教育在地国际化。阿联酋通过吸引世界知名大学设立分校,引进国外优质教育资源,促进了其高等教育质量和国际知名度的提高,也提升了学生的国际化水平,推动了经济的发展及转型,但也存在着境外分校对阿联酋本土文化形成冲击、对境外分校的质量监管不到位等问题。借鉴其经验,我国中外合作办学的优化和在地国际化的推进,需要进一步完善对中外合作大学的质量监管体系、正确处理好国际化与本土化之间的关系。

关键词：阿联酋高等教育在地国际化境外分校

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Rare earth oxides and their supported noble metals in application of environmental catalysis

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Journal of Rare Earths 2020年第8期38卷 819-839,I0001页

作者： Zhiquan Hou Wenbo Pei Xing Zhang kunfeng Zhang Yuxi Liu Jiguang Deng Lin Jing Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemistry and Chemical EngineeringCollege of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

Volatile organic compounds(VOCs),methane,carbon monoxide,soot,automotive exhaust,and nitrogen oxides are harmful to the atmosphere and human *** is urgent to strictly control their *** catalysis is an effective pathway for the removal of these pollutants,and the critical issue is the development of novel and high-performance *** this review,we briefly summarize the preparation methods,physicochemical properties,catalytic activities,and related reaction mechanisms for the above pollutants removal of the rare earth oxides,mixed rare earth oxide,rare earth oxidesupported noble metal,and mixed rare earth oxide-supported noble metal catalysts that have been investigated by our group and other *** was found that catalytic performance was associated with the factors,such as specific surface area,pore structure,particle size and dispersion,adsorbed oxygen species concentration,reducibility,reactant activation ability or interaction between metal nanoparticles and ***,we also envision the development trend of such a topic in future work.

关键词： Volatile organic compound Atmospheric pollutant Rare earth oxide Mixed rare earth oxide Supported noble metal catalyst Porous mixed rare earth oxide

Language Ability or Personality Works?:The Return to Possessing a Global English Test Certificate for College Graduates in China

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ECNU Review of Education 2018年第2期1卷 74-101页

作者： Sheng Cui kunfeng Pan Yangyong Ye Renmin University of China

Purpose-English language skills have great influence on labors’earnings from the global *** reveal the economic returns to English language ability in Chinese labor market,we investigate how the global English test certificate affects college graduates’***/Approach/Methods-We adopt the ordinary least squares(OLS)and propensity score matching(PSM)methods,using data from Chinese Education Panel Survey(CEPS).Findings-The results indicate that with English test scores controlled,possessing global English test certificates have an additional positive effect on wage premiums whereas domestic English test certificates do *** for college graduates in China,the act of chasing certificates represents proactivity and is rewarded at the initial employment ***/Value-Our findings imply that global English test has great comprehensive value in labor market:the certificate is not only the important signal to students’English language,but the crucial indicator to one’s productivity personality which is rewarded at the initial employment stage.

关键词： English language ability College Entrance Examination score wage premium human capital proactivity

新疆吾合沙鲁铜矿床含铜岩系安居安组下段砂岩粒度特征与沉积环境分析

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现代地质 2024年第4期38卷 1134-1146页

作者：柳坤峰冯昌荣徐磊祁晓鹏蔡振锋谢晋翟黎明雷浩中陕核工业集团地质调查院有限公司陕西西安710100 新疆维吾尔自治区地质矿产勘查开发局第二地质大队新疆喀什844002

吾合沙鲁铜矿床位于新疆西南天山乌恰前陆盆地北缘,该盆地内沉积大套中生代—新生代陆相砂体,是该区域铅锌、铜、铀等砂岩型矿床的重要含矿岩系。关于该矿床沉积学方面的研究工作薄弱,长期制约着对区域成矿规律的深入认识及对矿床勘查... 详细信息

吾合沙鲁铜矿床位于新疆西南天山乌恰前陆盆地北缘,该盆地内沉积大套中生代—新生代陆相砂体,是该区域铅锌、铜、铀等砂岩型矿床的重要含矿岩系。关于该矿床沉积学方面的研究工作薄弱,长期制约着对区域成矿规律的深入认识及对矿床勘查的有效指导。本文以吾合沙鲁铜矿床含铜岩系新近系中新统安居安组下段碎屑沉积岩为主要研究对象,以沉积学、层序地层学、岩相古地理学和碎屑岩石学理论为指导,系统采集矿区内安居安组下段砂岩粒度分析样品,采用碎屑岩粒度分析测试手段,对沉积物展开细致和深入的研究。结果表明,安居安组沉积相类型与辫状河三角洲相沉积特征一致,在各岩性段内识别出辫状河三角洲平原和辫状河三角洲前缘2种沉积亚相及分流河道砂坝、陆上天然堤、水下分流河道、分流间湾、河口砂坝及远砂坝6种沉积微相。安居安组下段为研究区主要富铜层位,其中水下分流河道微相和分流河道砂坝微相,可作为吾合沙鲁地区铜矿勘查的重点目标。研究成果可为吾合沙鲁铜矿周边及外围资源远景预测提供找矿思路,为区域探寻砂岩型铜矿提供新的借鉴。

关键词：砂岩型铜矿粒度特征沉积环境安居安组吾合沙鲁乌恰盆地