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New robust fault-tolerant controller for self-repairing flight control systems

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Journal of Systems Engineering and Electronics 2011年第1期22卷 77-82页

作者： Zhang Ren Wei Wang zhen shen National Key Laboratory of Science and Technology on Holistic Control Beihang University Beijing 100191 E R. China Civil Aviation Management Institute of China Beijing 100102 P. R. China

A new robust fault-tolerant controller scheme integrating a main controller and a compensator for the self-repairing flight control system is *** main controller is designed for high performance of the original faultless *** compensating controller can be seen as a standalone loop added to the system to compensate the effects of fault guaranteeing the stability of the system.A design method is proposed using nonlinear dynamic inverse control as the main controller and nonlinear extended state observer-based *** stability of the whole closed-loop system is *** and validity of the new controller is demonstrated with an aircraft simulation example.

关键词： robust control self-repairing flight control nonlinear dynamic control extended state observer compensator.

High-throughput computation and structure prototype analysis for two-dimensional ferromagnetic materials

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npj Computational Materials 2022年第1期8卷 1238-1244页

作者： zhen-Xiong shen Chuanxun Su Lixin He Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei230026China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei230026China

We perform high-throughput first-principles computations to search the high Curie temperature (T_(C)) two-dimensional ferromagnetic (2DFM) *** identify 79 2DFM materials and calculate their T_(C),in which Co_(2)F_(2) has the highest T_(C) = 541 K,well above the room *** 79 2DFM materials are classified into different structural prototypes according to their structural *** perform sure independence screening and sparsifying operator (SISSO) analysis to explore the relation between T_(C) and the material *** results suggest that the 2DFM materials with shorter distance between the magnetic atoms,larger local magnetic moments and more neighboring magnetic atoms are more likely to have higher T_(C).

关键词： materials. analysis dimensional

Manufacture and Performance of Ionic Polymer-Metal Composites

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Journal of Bionic Engineering 2007年第3期4卷 143-149页

作者： Min Yu Hui shen zhen-dong Dai Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

Ion-exchange Polymer Metal Composites （IPMC） are a new class of intelligent material that can be used effectively as actuators and artificial muscles. IPMC was fabricated and its displacement and force characteristics were investigated with respect to voltage, frequency and waveform of the controlling signal. A square waveform input generated slightly larger displacement and force than sinusoidal or triangular waveform. When the voltage was increased and the frequency was decreased, displacement and force were both increased. However, although the bending deformation of IPMC was large, the output force was much lower than we expected. Improvement of the force output is key and is the main obstacle to be overcome in order to make IPMC of practical use.

关键词： IPMC artificial muscle

Finite Groups with Some Pronormal Subgroups

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Acta Mathematica Sinica,English Series 2011年第4期27卷 715-724页

作者： zhen Cai shen Wu Jie SHI School of Mathematical Sciences Suzhou University Suzhou 215006 P. R. China School of Mathematics and Statistics Chongqing University of Arts and Sciences Chongqing 402160 P. R. China

A subgroup H of finite group G is called pronormal in G if for every element x of G, H is conjugate to Hx in （H, Hx）. A finite group G is called PRN-group if every cyclic subgroup of G of prime order or order 4 is pronormal in G. In this paper, we find all PRN-groups and classify minimal non-PRN-groups （non-PRN-group all of whose proper subgroups are PRN-groups）. At the end of the paper, we also classify the finite group G, all of whose second maximal subgroups are PRN-groups.

关键词： Pronormal subgroups PRN-groups minimal non-PRN-groups PN-groups minimalsubgroups p-nilpotent groups

Interconversion of photon-phonon in a silica optomechanical microresonator

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Science China(Physics,Mechanics & Astronomy) 2015年第5期58卷 64-69页

作者： DONG ChunHua shen zhen ZOU ChangLing GUO GuangCan Key Laboratory of Quantum Information Chinese Academy of Sciences University of Science and Technology of China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

In an optomechanical resonator, the optical and mechanical excitations can be coherently converted, which induces a transparency window for a weak probe laser beam. Here, we report an experimental study of transient optomechanically induced transparency(OMIT) using the silica microsphere with the breathing modes. The transient OMIT behavior obtained are in good agreement with theoretical calculations. In addition, the coherent interconversion between optical and mechanical excitations that can be used for light storage and readout has also been studied here. Our experimental results indicate that the light storage is closely related to the process of OMIT, and the photon-phonon conversion can be further applied to optical wavelength or optical mode conversion.

关键词： cavity optomechanics optomechanically induced transparency microsphere

Timely recognition of Amyand's hernia with appendicitis in infants

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World Journal of Pediatrics 2015年第4期11卷 392-394页

作者： zhen shen Shan zheng Children's Hospital Fudan University399 Wanyuan RoadShanghai 201102China Shanghai Key Laboratory of Birth Defect

Background:Amyand's hernia with acute appendicitis is rare in infants and is mostly delayed in diagnosis and treatment,resulting in a high ***:We presented two cases of infantile Amyand's hernia with acute ***:Early surgical interventions were performed and both patients recovered without ***:A practical strategy for this entity is to be aware of the rare disease and to perform early surgical exploration for suspected cases.

关键词： Amyand's hernia appendicitis infant morbidity

Charge Rate-Dependent Decomposition Mechanism of Toroidal Li_(2)O_(2)in Li-O_(2)Batteries

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Chinese Journal of Chemistry 2021年第10期39卷 2668-2672页

作者： zhen-zhen shen Chi Zhou Rui Wen Li-Jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Science(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Main observation and conclusion Using in situ atomic force microscopy,we visualized the oxidation dynamic process of toroidal lithium peroxide(Li_(2)O_(2))in a working Li-O2 battery and clarified the correlation between the decomposition behavior and the charging *** was found that at a low charge rate,the decomposition could occur at the Li_(2)O_(2)/electrolyte interface,providing strong evidence that a tiny current is allowed to pass through the bulk phase of toroidal Li_(2)O_(2).Further,the evolution of the periphery thickness,diameter and center thickness of the toroid as a function of charge capacity was quantitatively *** the early stage of charging,the diameter of the toroid radially shrinks and the shrinking rate slows down in the later ***,the periphery thickness of the toroid decreases at a faster and uniform rate,while the center thickness decreases obviously in the later stage of *** the charging rate promotes the decomposition occurring at the Li_(2)O_(2)/electrode interface,causing direct desorption of the Li_(2)O_(2)from the electrode and irreversible capacity degradation.

关键词： Li-0_(2)Batteries Scanning probe microscopy Toroidal Li_(2)0_(2) Oxidation Structure-activity relationships

Practice of precision surgery in primary liver cancer

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 108-109页

作者： Yun Hu zhen-Hua shen Department of Pathology Huzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical UniversityHuzhou 313000China Department of General Surgery Huzhou Central HospitalHuzhou 313003China

Primary liver cancer(PLC)is mainly composed of three major cancer:intrahepatic cholangiocarcinoma,hepatocellular carcinoma and mixed hepatocellular-cholangiocellular *** is the sixth most common cancer and the second ... 详细信息

关键词： cancer carcinoma. liver

Distributional characteristics and sources of elements in soil from typical area of Pearl River Delta economic zone, Guangdong Province, China

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Chinese Journal Of Geochemistry 2015年第3期34卷 299-310页

作者： Lei Dou Shu-zhen shen Hai-Yan Du Geological Survey of Guangdong Province Beijing Normal University Zhuhai Campus

Dongguan City, located in the Pearl River Delta economic zone of China, is famous for its rapid developing township-enterprises in the past 30 years. A total of 759 composite soil samples, including 606 surface soil samples and 153 deep soil samples, have been collected in the city. These samples have been analyzed for 13elements(Al, As, Cu, Cd, Co, Cr, Fe, Hg, Mn, Ni, Pb, Si,and Zn) and other parameters(p H values and organic matter) to evaluate the influence of anthropic activities on the soil environmental quality and to identify the spatial distribution of heavy metals and their possible sources. The results indicate that the average concentrations of heavy metals in soil were significantly lower than the threshold of the second grade of the Soil Environment Quality Standard in China(GB15618-1995) and the soil environmental quality in this area is comparatively good. But in comparison with local soil geochemical baseline values, As,Cd, Cu, Hg, Pb, and Zn have accumulated ***, the average concentrations of As, Cd, Cu, and Hg in the small part samples of the west plain and central areas are higher than the national second-grade quality standard, indicating some level of contamination. Multivariate and geostatistical methods have been applied to differentiate the influences of natural processes and human activities on the concentration of heavy metals in surface soils in the study area. Cluster and factor analyses result in the grouping of Al, As, Cr, Cu, Fe, Ni, and Si into factor F1; Co, Mn, Pb, and Zn into F2; and Cd and Hg into *** spatial pattern of the three factors may be well demonstrated by geostatistical analysis. It is shown that the first factor could be considered as a natural source controlled by parent material. The second factor could be referred to as ‘‘industrial and traffic pollution sources' '. The source of the third factor is mainly controlled by long-term anthropic activities, including agricultural activities, fossil f

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