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Dynamical analysis on splitting of subtropical high-pressure zone——Geostrophic effect

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Chinese Science Bulletin 1998年第15期43卷 1285-1289页

作者： jianping li Jifan Chou Lanzhou Univ Dept Atmospher Sci Lanzhou 730000 Peoples R China

Based on two simple dynamical models, the preliminary dynamical analysis of the splitting of subtropical high_pressure zone (SHPZ) without land_sea contrast and orographic effect is investigated. Results show that the... 详细信息

关键词： subtropical high_pressure zone splitting inhomogeneity.

Microstructure and properties in dissimilar/similar weld joints between DP780 and DP980 steels processed by fiber laser welding

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Journal of Materials Science & Technology 2017年第12期33卷 1561-1571页

作者： Hongshuang Di Qian Sun Xiaonan Wang jianping li State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Shagang School of Iron and Steel Soochow UniversitySuzhou 215021China

The microstructure and mechanical properties（strength, fatigue and formability） of dissimilar/similar weld joints between DP780 and DP980 steels were studied. The microstructure in fusion zone（FZ） was lath martensite（LM）, and alloying elements in the FZ were uniformly distributed. The hardness in the FZ of dissimilar weld joint was similar to the average value（375 HV） of the two similar weld joints. The microstructural evolution in heat affected zone（HAZ） of dissimilar/similar weld joints was as follows：LM（coarse-grained HAZ） →finer LM（fine-grained HAZ） →M-A constituent and ferrite（intercritically HAZ） →tempered martensite（TM） and ferrite（sub-critical HAZ）. Lower hardness in intercritically HAZ and sub-critical HAZ（softening zones） was observed compared to base metal（BM） in dissimilar/similar weld joints. The size of softening zone was 0.2-0.3 mm and reduction in hardness was ~7.6%-12.7% of BM in all the weld joints, which did not influence the tensile properties of weld joints such that fracture location was in BM. Formability of dissimilar weld joints was inferior compared to similar weld joints because of the softening zone, non-uniform microstructure and hardness on the two sides of FZ. The effect of microstructure on fatigue life was not influenced due to the presence of welding concavity.

关键词： Dual phase steel Laser welding Dissimilar weld joints Microstructure Mechanical properties Formability

Fast assignment reduction in inconsistent incomplete decision systems

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Journal of Systems Engineering and Electronics 2014年第1期25卷 83-94页

作者： Min li Shaobo Deng Shengzhong Feng jianping Fan Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Nanchang Institute of Technology Graduate School of Chinese Academy of Sciences Key Laboratory of Intelligent Information Processing Institute of Computing TechnologyChinese Academy of Sciences

This paper focuses on fast algorithm for computing the assignment reduct in inconsistent incomplete decision systems. It is quite inconvenient to judge the assignment reduct directly ac-cording to its definition. We propose the judgment theorem for the assignment reduct in the inconsistent incomplete decision system, which greatly simplifies judging this type reduct. On such basis, we derive a novel attribute significance measure and construct the fast assignment reduction algorithm （F-ARA）, intended for com-puting the assignment reduct in inconsistent incomplete decision systems. Final y, we make a comparison between F-ARA and the discernibility matrix-based method by experiments on 13 Univer-sity of California at Irvine （UCI） datasets, and the experimental results prove that F-ARA is efficient and feasible.

关键词： assignment reduction upper approximation reduction,inconsistent incomplete decision system rough set.

Investigation into Pilot Handling Qualities in Teleoperation Rendezvous and Docking with Time Delay

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Chinese Journal of Aeronautics 2012年第4期25卷 622-630页

作者： ZHOU Jianyong ZHOU jianping JIANG Zicheng li Haiyang College of Aerospace and Material Engineering National University of Defense TechnologyChangsha 410073China

Teleoperation rendezvous and docking can be used as a backup for autonomous rendezvous and docking（RVD） for an unmanned spacecraft when the autonomous system is failure or for guiding the chaser docking with an uncooperative *** theoretical model for analyzing the handling qualities in teleoperation RVD process is established based on the previous studies conducted by National Aeronautics and Space Administration（NASA）.The predictive factor is introduced to describe the pilot＇s predictive ability in the teleoperation tasks with time delay,which interrelates with the skills of a pilot and the predictive assist approach used in the tasks such as the predictive display *** on the semi-physical simulation system in our laboratory,900 experiments at two levels of time delay are carried out by 18 volunteers for validating the established *** experimental results demonstrate the correctness of the theoretical model and indicate that a skilled pilot has a predictive ability of approximately 0.9 in teleoperation RVD *** theoretical analysis shows that the handling qualities are greatly affected by the time delay and the predictive factor,and it is impossible to achieve a teleoperation RVD task for the skilled pilot when the time delay is larger than 9.0 s.

关键词： teleoperation rendezvous and docking handling quality theoretical model time delay experimental validation

Unified Description of the EMC Effect and Nuclear Shadowing Effect

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Chinese Physics Letters 1993年第11期10卷 648-651页

作者： li Guanglie SHEN jianping YU Mingjian Institute of High Energy Physics Academia Sinicat Bering 100039

The parton evolution model is improved by using the modified Alteralli-Parisi equation which can describe the nuclear shadowing and antishadowing effects in the small x *** the theoretical framework of the improved parton evolution modelt the unified description of the European Muon Collaboration(EMC)effect,and nuclear shadowing and antishad owing effects is given without introducing the nuclear shadowing factor.

关键词： unified introducing equation

Using kerogen FTIR parameters for determination of organic facies

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Chinese Science Bulletin 1998年第8期43卷 681-684页

作者： jianping Chen Ping Luo Jinchao li China Natl Petr Corp Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China

FTIR spectrum data can not only be used to indicate kerogen type and maturity, but also to determine organic facies of source rock. Aliphatic chain structure indices (ACSI) and an aromatic structure index (ASI) are introduced to divide sedimentary organic facies of different source rocks into three types: swamp, swamp_lacustrine and lacustrine facies. The indices also reveal the fine difference of the organic matters, such as kerogen types, petroleum potential and nature of hydrocarbon products.

关键词： organic facies FTIR aliphatic chain structure indices (ACSI) aromatic structure index (ASI) source rocks.

Nuclear Drell-Yan Process in the Improved Parton Evolution Model

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Chinese Physics Letters 1995年第6期12卷 348-350页

作者： li Guanglie SHEN jianping YU Mingjian Institute of High Energy Physics Academia SinicaBeiing 100039 Institute of Theoretical Physics Academia SinicaBeing 100080

By using the parton momentum distribution of the bound nucleon given by the improved parton evolution model,we calculate the nuclear Drell-Yan ratios of nuclei:C,Ca,Fe and W to *** calculated results are in qualitativ... 详细信息

关键词： qualitative momentum distribution

Image-based numerical study of three-dimensional meso-structure effects on damage and failure of heterogeneous coal-rock under dynamic impact loads

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Particuology 2020年第4期18卷 132-141页

作者： Kehong Zheng Bingjing Qiu Zhenyu Wang Xuefeng li jianping li Kuidong Gao College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing 210000China College of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116China College of Mechanical&Electrical Engineering Shandong University of Science&Technology Qingdao 266000China

This paper proposes a numerical three-dimensional(3D)mesoscopic approach based on the discrete element method combined with X-ray computed tomography(XCT)images to characterize the dynamic impact behavior of heterogeneous coal-rock(HCR).The dynamic impact loading in three directions was modelled to investigate the effects of the 3D meso-structure on the failure patterns and fracture mechanism,with different impact *** XCT image-based discrete element model of HCR was calibrated through appropriate standard uniaxial compression *** simulations were carried out to investigate how the breakage behaviors are affected by different loading directions with different impact *** loading direction,input energy,and spatial distribution of the mineral phase had a remarkable influence on the failure patterns and load-carrying *** shape of the gangue phase and the approximate location of the gangue interfaces are key parameters to consider when investigating the failure patterns and fracture mechanism of heterogeneous rock *** damage and fracture tended to propagate from the surfaces to the HCR *** gangue phase area contacting the loading wall,growth direction of the strong gangue interfaces,and loading directions greatly influenced the failure patterns of the heterogeneous rock materials.

关键词： Heterogeneous coal-rock Impact loads X-ray computed tomography(XCT) 3D image-based discrete element modelling Failure pattern

An Efficient, Three-component One-pot Preparation of 1,4-Dihydropyridines Containing Novel Substituted Pyrazole under Sulfamic Acid Catalysis

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Chinese Journal of Chemistry 2011年第3期29卷 511-514页

作者： li, jianping Qiu, Jikuan li, Huijuan Zhang, Guisheng College of Chemistry and Environmental Science Key Labaratory of Green Chemical Media and Reactions Ministry of Education Henan Normal University Xinxiang Henan 453007 China

An efficient approach to 1,4-dihydropyridines containing novel substituted pyrazole is achieved via threecomponent reaction of pyrazolyl aldehyde, β-ketoester, and ammonium acetate in one-pot under sulfamic acid cata... 详细信息

关键词： Hantzsch reaction 1,4-dihydropyridines pyrazole sulfamic acid catalysis synthesis