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Chinese Journal of Aeronautics 2024年第10期37卷 471-482页

作者： Yingke yang Dongsheng LI Yunong ZHAI Jie WANG Lei XUE Zhiyong yang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 3158002China COMAC Shanghai Aircraft Manufacturing Co. Ltd.Shanghai 201324China

Robots are finding increasing application in aircraft composite structure assembly due to their flexibility and the growing demand of aircraft manufacturers for high production *** contact force of the composite frame in a robotic assembly of the aircraft composite fuselage panel can hardly be controlled due to the multi-surface variable contact stiffness caused by compliance and complex shape with multiple mating *** paper proposes a robotic assembly system for the aircraft composite fuselage frame with a compliant contact force control strategy using the Gaussian process surrogate ***,a robotic assembly system is introduced,and the global coordinate system transformation model is ***,a compliant force control architecture is designed to generate the desired output ***,a Gaussian process surrogate model with uncertainties is utilized to model the complicated relationship between the robot’s output force and the normal contact force acting on the mating surface of the composite ***,an optimal contact force control strategy is implemented to improve the contact ***,an experiment demonstrates that the proposed methodology can ensure that the contact force on each surface is within the limit of the engineering specification and uniformly distributed,improving the quality compared to the traditional assembly process.

关键词： Aircraft Composite structure assembly Multi-surface contact Compliant control Gaussian process Uncertainty

在驱力均衡中国际人力资源战略发展实证研究——以上海地区跨国公司为例

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上海管理科学 2005年第6期27卷 45-47页

作者：廖勇凯杨湘怡上海复旦大学管理学院

本文透过文献探讨与集群分析的实证研究,划分上海地区跨国公司国际人力资源战略可分成“放任无主人力资源战略”、“总部操控人力资源战略”、“地区自治人力资源战略”、以及“收放兼顾人力资源战略” 四种类型,并在此基础上建议跨国... 详细信息

本文透过文献探讨与集群分析的实证研究,划分上海地区跨国公司国际人力资源战略可分成“放任无主人力资源战略”、“总部操控人力资源战略”、“地区自治人力资源战略”、以及“收放兼顾人力资源战略” 四种类型,并在此基础上建议跨国公司未来上朝向本土化的国际人力资源战略发展方向。

关键词：跨国公司国际人力资源战略整合-反应模型上海地区

The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

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Journal of Meteorological Research 2024年第2期38卷 321-338页

作者： Lei yang Yongguang ZHENG Liaoning Meteorological Disaster Monitoring and Early Warning Center Shenyang 110166 National Meteorological Centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado Key Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast *** conditions(e.g.,water vapor,instability,and vertical wind shear)are known to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more *** on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit *** this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are *** is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the *** highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast *** can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this ***,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the *** NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water ***,there are lower lifting condensation levels and stronger 0-6-and 0-1-km vertical wind shears in these *** findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

Mars exploration——In situ K-Ar dating of jarosite

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Science China Earth Sciences 2024年第3期67卷 641-656页

作者： Jing yang Dewen ZHENG Ying WU Hong CHEN Li yang Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

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考虑出行者感知的城市轨道交通接驳服务评价

城市轨道交通研究 2020年第8期23卷 40-43,49页

作者：乔相荣姜珊巩舜妹杨祥一深圳市综合交通设计研究院有限公司深圳518003 南京市城市与交通规划设计研究院股份有限公司南京210008 宿州学院资源与土木工程学院宿州234099

以城市轨道交通接驳过程中交通设施给出行者带来的约束为研究对象,建立了城市轨道交通接驳感知评价模型(Rasch模型)。基于西安市城市轨道交通乘客的问卷调查,分析城市轨道交通不同接驳方式对不同性别、年龄、收入,以及接驳过程满意度的... 详细信息

以城市轨道交通接驳过程中交通设施给出行者带来的约束为研究对象,建立了城市轨道交通接驳感知评价模型(Rasch模型)。基于西安市城市轨道交通乘客的问卷调查,分析城市轨道交通不同接驳方式对不同性别、年龄、收入,以及接驳过程满意度的个体产生的出行感知的影响,并从降低接驳难度角度提出接驳意见。调查结果表明,选择道路公交作为接驳方式时,道路公交的运输能力适配性、线网布局匹配性、运输准确性、运营时间匹配性等对不同的人有一定的感知难度;选择步行及自行车等慢行接驳方式时,人们对慢行标志辨认度、骑行环境障碍性、骑行环境安全性、骑行环境舒适性的感知难度较大;选择小汽车作为接驳方式时,人们对小汽车的停车便捷性、收费情况、停车场设置情况等较为敏感。

关键词：城市轨道交通接驳服务评价,出行感知 Rasch模型

PARE:Privacy-Preserving Data Reliability Evaluation for Spatial Crowdsourcing in Internet of Things

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Computers, Materials & Continua 2024年第8期80卷 3067-3084页

作者： Peicong He yang Xin Yixian yang School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing100876China

The proliferation of intelligent,connected Internet of Things(IoT)devices facilitates data ***,task workers may be reluctant to participate in data collection due to privacy concerns,and task requesters may be concerned about the validity of the collected ***,it is vital to evaluate the quality of the data collected by the task workers while protecting privacy in spatial crowdsourcing(SC)data collection tasks with *** this end,this paper proposes a privacy-preserving data reliability evaluation for SC in IoT,named ***,we design a data uploading format using blockchain and Paillier homomorphic cryptosystem,providing unchangeable and traceable data while overcoming privacy ***,based on the uploaded data,we propose a method to determine the approximate correct value region without knowing the exact ***,we offer a data filtering mechanism based on the Paillier cryptosystem using this value *** evaluation and analysis results show that PARE outperforms the existing solution in terms of performance and privacy protection.

关键词： Spatial crowdsourcing privacy-preserving data evaluation IoT blockchain

Non-contact air-coupled transducers Lamb wave signal multipath effect and blind separation for different modes using PZT as receiver

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Chinese Journal of Aeronautics 2024年第10期37卷 424-434页

作者： Desheng WU Zhibo yang Yu RUAN Wenbo LI Lijuan yang Xuefeng CHEN National Key Lab of Aerospace Power System and Plasma Technology Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Due to the complexity and faintness of the detection wave patterns obtained by aircoupled transducers,if it is possible to effectively separate the various modes and obtain nondispersive signals for more accurate detection and positioning,it will help to improve the accuracy and reliability of air-coupled ultrasonic Lamb wave detection,providing better technical support for the application and development of related *** of the increased complexity of aircoupled signals,there is no definite theoretical formula to describe the mode changes of aircoupled signals,so the method based on blind separation has unique *** address these challenges,the paper proposes a single-channel blind source separation(SCBSS)*** effectiveness of this method is evaluated through simulations and experiments,demonstrating favorable separation results and efficient computational *** work first conducts an in-depth analysis of the signal characteristics of air-coupled ultrasonic non-destructive testing,and simulates the ultrasonic excitation conditions of air-coupled sensors through finite element *** study of modal changes and multipath effects caused by the variation of the incidence angle of the ACT signal is carried out,and the situation of the Lamb wave signal excited by ACT at the receiving end is *** combining ACT with PZT signals,the ultrasonic signals of air-coupled Lamb waves are compared and studied,and their modal purification is carried out.

关键词： Air-coupled transducers Lamb wave Mode separation Blind source separation Non-destructive testing

Facile access to C-N bonds via unexpected side reactions of Knoevenagel condensation and their application in high-efficiency organic solar cells

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Science China Chemistry 2024年第1期67卷 323-329页

作者： Daobin yang Shuncheng yang Hongqian Wang Lin Xie Pengyu Yan Ziyi Ge Zhejiang Engineering Research Center for Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The construction of C-N bonds is of great importance in the fields of biology,medicine,chemistry and materials ***,the replacement of organic base from pyridine to piperidine in the Knoevenagel condensation process unexpectedly yields a series of novel organic molecules containing C-N ***,the synthesis method does not require any external transition-metals catalysis,and photo-/***,when the new compound 1b is added as a third component to a well-known binary system of PM6:Y6,the efficiency of the organic solar cell is significantly improved,resulting in an outstanding efficiency of 18.0%,which is one of the highest values reported to date for PM6:Y6-based ternary organic solar cells.

关键词： C-N bonds Knoevenagel condensation cross-coupling reaction third component organic solar cells

A new fluorocarbon adhesive:Inhibiting agglomeration during combustion of propellant via efficient F-Al_(2)O_(3) preignition reaction

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Carbon Energy 2024年第6期6卷 292-305页

作者： Qifa Yao Min Xia Chao Wang Fanzhi yang Wei yang Yunjun Luo School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Key Laboratory of High Energy Density Materials Ministry of EducationBeijing Institute of TechnologyBeijingChina School of Aerospace Engineering Beijing Institute of TechnologyBeijingChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijingChina

Inhibiting the agglomeration of molten aluminum particles packed in the binder network is a promising scheme to achieve efficient combustion of solid *** this investigation,the hydroxyl-terminated structured fluorinated alcohol compound(PFD)was introduced to modify the traditional polyethylene glycol/polytetrahydrofuran block copolymerization(HTPE)binder;that is,a unique fluorinated polyether(FTPE)binder was synthesized by embedding fluorinated organic segments into the HTPE binder via crosslinking *** FTPE was applied in aluminum-based propellants for the first *** to the complete release of fluorinated organic active segments in the range of 300℃to 400℃,the burning rate of FTPEbased propellant increased from 4.07(0%PFD)to 6.36 mm/s(5%PFD),increased by 56.27%under 1 *** reaction heat of FTPE propellants increased from 5.95(0%PFD)to 7.18 MJ/kg(5%PFD)under 3.0 MPa,indicating that HTPE binder modified with PFD would be conducive to inhibiting the D90 of condensed combustion products(CCPs)dropped by 81.84%from 75.46(0%PFD)to 13.71μm(5%PFD)under 3.0 MPa,in consistent with the significant reduction of aluminum agglomerates observed on the quenched burning surface of the *** results demonstrated that a novel FTPE binder with PFD can release fluorinated organic active segments,which motivate preignition reaction with the alumina shell in the early stage of aluminum combustion,and then enhance the melting diffusion effect of aluminum to inhibit the agglomeration.

关键词： agglomeration characteristics aluminum particles combustion fluorine alcohol compounds HTPE propellants

A fuse-based DC circuit breaker with vacuum interrupter enhanced by an external transverse magnetic field

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High Voltage 2024年第3期9卷 710-720页

作者： Yu Xiao Yi Wu Yifei Wu Fei yang Mingzhe Rong Zhuo yang State Key Laboratory of Electrical Insulation and Power Equipment School of Electric EngineeringXi'an Jiaotong UniversityXi'anChina State Grid Shaanxi Electric Power Company Limited Xi'anChina

Due to the increasing power system capacity,the interruption of large fault currents has gradually become a major challenge in power *** the moment,such currents are interrupted mainly via circuit breakers based on the method of active current ***,these types of circuit breakers tend to be costly and *** possible alternative—a fuse-based circuit breaker with current commutation process enhanced by an external transverse magnetic field(ETMF)—is proposed by the *** main advantage lies in the fast current commutation achieved by an ETMF-enhanced three-stage increase of the vacuum arc *** study of the current commutation process is mainly represented by the authors,and the influencing factors of the current commutation—contact opening speed and ETMF current—are *** last,the proposed circuit breaker is verified by an experiment,whose results show that a short-circuit current of 42 kA can be interrupted within just 2 ms.

关键词： vacuum transverse interrupt