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760 results on '"Li Xianhua"'

1. A note on the structure of a finite group G having a subgroup H maximal in 〈H, Hg〉

Author

Xu Yong, Li Xianhua, and Chen Guiyun

Subjects
finite group, chief factor, solvable, supersolvable, 20d10, 20d15, Mathematics, QA1-939
Abstract

Let G be a finite group and H ≤ G. The authors study the structure of finite groups G having a subgroup H which is maximal in 〈H, Hg〉 for some g ∈ G. Some results on the structure of 〈H, Hg〉 and G are set up. Especially, a generalization of Baer′s theorem is established.

Published
2019
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4. Research and Simulation of the Kinematics of Dual-arm 6R Service Robot

Author

Li Xianhua, Sun Qing, Zhang Leigang, and Zhang Jun

Subjects
Dual-arm, Inverse kinematics, Geometrical method, Coordinate projection method, Simulation verification, Mechanical engineering and machinery, TJ1-1570
Abstract

Aiming at the inverse solution problem of the kinematics of dual-arm service robot,a inverse kinematics solution is proposed according to its configuration characteristics. Firstly,according to the structure characteristics of the manipulator,the forward kinematics model of dual-arm is got by using the method of standard DH modeling. A group of completely generalized coordinates is obtained by inverse transformation method of manipulator posture matrix using Euler angles. Then,the inverse kinematics of dual-arm6 R robot is solved by geometrical method and coordinate projection method. After analysis and calculation,the closed solutions of 8 groups can be obtained,and the optimal solution is selected. Finally,a 3 D simulation platform is established to verify the correctness of inverse kinematics based on MATLAB,and it lays the foundation for the trajectory planning and collision avoidance of manipulator.

Published
2018
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5. Analysis and Simulation of Collaborative Space of the Dual Arm 6R Service Robot

Author

Li Xianhua, Sun Qing, Fan Kaijie, and Zhang Leigang

Subjects
Dual arm, Monte Carlo method, Traversal search comparison method, Collaborative space, Mechanical engineering and machinery, TJ1-1570
Abstract

Aiming at collaborative space problem of the dual arm 6 R service robot,the Monte Carlo and traversal search comparison method are used for analysis according to its configuration characteristics. Firstly,according to the configuration of the manipulator,the standard DH method is used to construct the model,and then the forward kinematics equation of the arms is obtained. Secondly,the work space of each arm is got by using Monte Carlo method. Then,the collaborative space of the arms is obtained by using the traversal search comparison method,and the range of the joint angle of the dual arms is obtained through kinematics inverse method. Finally,the MATLAB toolbox is used to build the simulation platform and the algorithm is written to verify the correctness of the above analysis,and the foundation for the follow-up coordinated operation and trajectory planning is laid.

Published
2018
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7. On CSQ-normal subgroups of finite groups

Author

Xu Yong and Li Xianhua

Subjects
csq-normal subgroup, nilpotent subgroup, supersolvable subgroup, 20d10, 20d15, Mathematics, QA1-939
Abstract

We introduce a new subgroup embedding property of finite groups called CSQ-normality of subgroups. Using this subgroup property, we determine the structure of finite groups with some CSQ-normal subgroups of Sylow subgroups. As an application of our results, some recent results are generalized.

Published
2016
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8. p-sylowizers and p-nilpotency of finite groups

Author

Gao, Yaxin, Li, Xianhua, and Lei, Donglin

Subjects
Mathematics - Group Theory
Abstract

In this paper, we investigate the structure of finite group G by assuming that the intersections between p-sylowizers of some p-subgroups of G and $O^p(G)$ are S-permutable in G. We obtain some criterions for p-nilpotency of a finite group.

Published
2023

10. Characteristics, treatments, in-hospital and long-term outcomes among inpatients with acute exacerbation of chronic obstructive pulmonary disease in China: sex differences in a large cohort study

Author

Zhang, Jiarui, Yi, Qun, Zhou, Chen, Luo, Yuanming, Wei, Hailong, Ge, Huiqing, Liu, Huiguo, Zhang, Jianchu, Li, Xianhua, Xie, Xiufang, Pan, Pinhua, Yi, Mengqiu, Cheng, Lina, Zhou, Hui, Liu, Liang, Aili, Adila, Liu, Yu, Peng, Lige, Pu, Jiaqi, and Zhou, Haixia

Published
2024
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19. Return to the Moon: New perspectives on lunar exploration

Author

Lin, Yangting, Yang, Wei, Zhang, Hui, Hui, Hejiu, Hu, Sen, Xiao, Long, Liu, Jianzhong, Xiao, Zhiyong, Yue, Zongyu, Zhang, Jinhai, Liu, Yang, Yang, Jing, Lin, Honglei, Zhang, Aicheng, Guo, Dijun, Gou, Sheng, Xu, Lin, He, Yuyang, Zhang, Xianguo, Qin, Liping, Ling, Zongcheng, Li, Xiongyao, Du, Aimin, He, Huaiyu, Zhang, Peng, Cao, Jinbin, and Li, Xianhua

Published
2024
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22. A solar wind-derived water reservoir on the Moon hosted by impact glass beads

Author

He, Huicun, Ji, Jianglong, Zhang, Yue, Hu, Sen, Lin, Yangting, Hui, Hejiu, Hao, Jialong, Li, Ruiying, Yang, Wei, Tian, Hengci, Zhang, Chi, Anand, Mahesh, Tartèse, Romain, Gu, Lixin, Li, Jinhua, Zhang, Di, Mao, Qian, Jia, Lihui, Li, Xiaoguang, Chen, Yi, Zhang, Li, Ni, Huaiwei, Wu, Shitou, Wang, Hao, Li, Qiuli, He, Huaiyu, Li, Xianhua, and Wu, Fuyuan

Published
2023
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27. The fall, recovery, classification, and initial characterization of the Hamburg, Michigan H4 chondrite.

Author

Heck, Philipp R, Greer, Jennika, Boesenberg, Joseph S, Bouvier, Audrey, Caffee, Marc W, Cassata, William S, Corrigan, Catherine, Davis, Andrew M, Davis, Donald W, Fries, Marc, Hankey, Mike, Jenniskens, Peter, Schmitt-Kopplin, Philippe, Sheu, Shannon, Trappitsch, Reto, Velbel, Michael, Weller, Brandon, Welten, Kees, Yin, Qing-Zhu, Sanborn, Matthew E, Ziegler, Karen, Rowland, Douglas, Verosub, Kenneth L, Zhou, Qin, Liu, Yu, Tang, Guoqiang, Li, Qiuli, Li, Xianhua, and Zajacz, Zoltan

Subjects
Astronomical and Space Sciences, Geochemistry, Geology, Geochemistry & Geophysics
Abstract

The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic 3He, 21Ne, and 38Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic 10Be concentration point to a small 40-60 cm diameter meteoroid. An 40Ar-39Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA-ICPMS give an average Pb-Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb-Pb phosphate age of 4535.3 ± 9.5 Ma and U-Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system.

Published
2020

36. Distribution and Abundance of Solar Wind‐Derived Water in Chang'E‐5 Core Samples and Its Implications

Author

Tian, Heng‐Ci, primary, Hao, Jialong, additional, Lin, Yangting, additional, Xu, Yuchen, additional, Jin, Ziliang, additional, Zhang, Chi, additional, Yang, Wei, additional, Hu, Sen, additional, Li, Ruiying, additional, Yue, Zongyu, additional, Li, Qiuli, additional, Wei, Yong, additional, Li, Xianhua, additional, and Wu, Fuyuan, additional

Published
2024
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44. Effect of Al(OH)3prepared from fly ash on the structural and catalytic properties of g-C3N4-based materials

Author

Yu, Qingbo, Li, Xianhua, and Wang, Qingping

Abstract

In order to find the optimal combination method of secondary utilization of fly ash and graphite-phase carbon nitride (g-C3N4) modification, an efficient composite photocatalyst of γ-Al2O3/g-C3N4was obtained by calcining the composite precursors of Al(OH)3/ dicyandiamide (DCDA). The introduction of Al(OH)3prepared by combining fly ash into the precursors causes hydrogen-bonding interactions between Al(OH)3and DCDA, which facilitate the removal of N atoms from the edges of the CN framework of g-C3N4during condensation, and the composites prepared possess more cyano defects. In addition, γ-Al2O3and g-C3N4form a chemical bond at the interface, and this chemical bonding causes the density of the electron cloud in the vicinity of the N atoms to increase. Among them, the strongest chemical bonding between Al2O3and g-C3N4was observed in ACN-1, whereas the most cyanine defects were formed in ACN-1, which made ACN-1 exhibit the best photocatalytic degradation of methylene blue, which is 2.48 times higher than that of the pristine g-C3N4.

Published
2024
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45. Validation of the Rome Severity Classification of Chronic Obstructive Pulmonary Disease Exacerbation: A Multicenter Cohort Study

Author

Zeng,Jiaxin, Zhou,Chen, Yi,Qun, Luo,Yuanming, Wei,Hailong, Ge,Huiqing, Liu,Huiguo, Zhang,Jianchu, Li,Xianhua, Pan,Pinhua, Yi,Mengqiu, Cheng,Lina, Liu,Liang, Zhang,Jiarui, Peng,Lige, Pu,Jiaqi, Zhou,Haixia, Zeng,Jiaxin, Zhou,Chen, Yi,Qun, Luo,Yuanming, Wei,Hailong, Ge,Huiqing, Liu,Huiguo, Zhang,Jianchu, Li,Xianhua, Pan,Pinhua, Yi,Mengqiu, Cheng,Lina, Liu,Liang, Zhang,Jiarui, Peng,Lige, Pu,Jiaqi, and Zhou,Haixia

Abstract

Jiaxin Zeng,1,* Chen Zhou,2,* Qun Yi,1,3 Yuanming Luo,4 Hailong Wei,5 Huiqing Ge,6 Huiguo Liu,7 Jianchu Zhang,8 Xianhua Li,9 Pinhua Pan,10 Mengqiu Yi,11 Lina Cheng,11 Liang Liu,12 Jiarui Zhang,1 Lige Peng,1 Jiaqi Pu,1 Haixia Zhou1 On behalf of the MAGNET AECOPD Registry Investigators1Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China; 2Center of Infectious Diseases, Division of Infectious Diseases in State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China; 3Sichuan Cancer Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, People’s Republic of China; 4State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China; 5Department of Respiratory and Critical Care Medicine, People’s Hospital of Leshan, Leshan, Sichuan Province, People’s Republic of China; 6Department of Respiratory and Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, People’s Republic of China; 7Department of Respiratory and Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People’s Republic of China; 8Department of Respiratory and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People’s Republic of China; 9Department of Respiratory and Critical Care Medicine, The First People’s Hospital of Neijiang City, Neijiang, Sichuan Province, People’s Republic of China; 10Department of Respiratory and Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan Province, People’s Republic of China; 11Department of Emergency, First Peop

Published
2024

47. Validation of the Rome Severity Classification of Chronic Obstructive Pulmonary Disease Exacerbation: A Multicenter Cohort Study

Author

Zeng, Jiaxin, primary, Zhou, Chen, additional, Yi, Qun, additional, Luo, Yuanming, additional, Wei, Hailong, additional, Ge, Huiqing, additional, Liu, Huiguo, additional, Zhang, Jianchu, additional, Li, Xianhua, additional, Pan, Pinhua, additional, Yi, Mengqiu, additional, Cheng, Lina, additional, Liu, Liang, additional, Zhang, Jiarui, additional, Peng, Lige, additional, Pu, Jiaqi, additional, and Zhou, Haixia, additional

Published
2024
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