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Research of robust adaptive trajectory linearization control based on T-S fuzzy system

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Journal of Systems Engineering and Electronics 2008年第3期19卷 537-545页

作者： Jiang Changsheng Zhang chunyu Zhu Liang College of Automation Nanjing Univ. of Aeronautics and Astronautics Nanjing 210016 P. R. China National Key Laboratory of Fire Control Technology Luoyang 471009 P. R. China

A robust adaptive trajectory linearization control （RATLC） algorithm for a class of nonlinear systems with uncertainty and disturbance based on the T-S fuzzy system is presented. The unknown disturbance and uncertainty are estimated by the T-S fuzzy system, and a robust adaptive control law is designed by the Lyapunov theory. Irrespective of whether the dimensions of the system and the rules of the fuzzy system are large or small, there is only one parameter adjusting on line. Uniformly ultimately boundedness of all signals of the composite closed-loop system are proved by theory analysis. Finally, a numerical example is studied based on the proposed method. The simulation results demonstrate the effectiveness and robustness of the control scheme.

关键词： nonlinear system trajectory linearization control robust adaptive control T-S fuzzy system.

Cooperative Co-evolutionary Artificial Bee Colony Algorithm Based on Hierarchical Communication Model

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Chinese Journal of Electronics 2016年第3期25卷 570-576页

作者： HU chunyu LIU Hong ZHANG Peng School of Information Science and Engineering Shandong Normal University Shandong Provincial Key Laboratory for Novel Distributed Computer Software Technology

Canonical Artificial bee colony(ABC) algorithm with a single species is insufficient to extend the diversity of solutions and may be trapped into the local optimal solution. This paper proposes a new co-evolutionary ABC algorithm(HABC) based on Hierarchical communication model(HCM). HCM combines advantages of global and local communication pattern. With adjustment strategies on species and groups, HCM can reduce the computational complexity dynamically. Performance tests show that the HABC algorithm exhibit good performance on accuracy, robustness and convergence speed. Compared with ABC and Integrated co-evolution algorithm(IABC),HABC performs better in solving complex multimodal functions.

关键词： Artificial bee colony(ABC) algorithm Multi-species co-evolution Hierarchical communication model(HCM) Dynamical adjustment

Search for strong gravitational lensing effect in the current GRB data of BATSE

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Science China(Physics,Mechanics & Astronomy) 2014年第8期57卷 1592-1599页

作者： LI chunyu LI LiXin Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University

Because gamma-ray bursts （GRBs） trace the high-z universe, there is an appreciable probability for a GRB to be gravitational lensed by galaxies in the universe. Herein we consider the gravitational lensing effect of GRBs contributed by the dark matter halos in galaxies. Assuming that all halos have the singular isothermal sphere （SIS） mass profile in the mass range 101~h 1Mo 〈 M 〈 2×10^13h^-1M and all GRB samples follow the intrinsic redshift distribution and luminosity function derived from the Swift LGRBs sample, we calculated the gravitational lensing probability in BATSE, Swift/BAT and Fermi/GBM GRBs, re- spectively. With an derived probability result in BATSE GRBs, we searched for lensed GRB pairs in the BATSE5B GRB Spectral catalog. The search did not find any convincing gravitationally lensed events. We discuss our result and future obser- vations for GRB lensing observation.

关键词： star formation galactic halos gravitational lenses and luminous arcs γ-ray sources γ-ray bursts cosmology

Genetics and epigenetics of circadian rhythms and their potential roles in neuropsychiatric disorders

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Neuroscience Bulletin 2015年第1期31卷 141-159页

作者： chunyu Liu Michael Chung State Key Laboratory of Medical Genetics of China Department of Psychiatry University of Illinois at Chicago

Circadian rhythm alterations have been implicated in multiple neuropsychiatric disorders,particularly those of sleep,addiction,anxiety,and mood. Circadian rhythms are known to be maintained by a set of classic clock genes that form complex mutual and self-regulatory loops. While many other genes showing rhythmic expression have been identified by genome-wide studies,their roles in circadian regulation remain largely unknown. In attempts to directly connect circadian rhythms with neuropsychiatric disorders,genetic studies have identifi ed gene mutations associated with several rare sleep disorders or sleep-related traits. Other than that,genetic studies of circadian genes in psychiatric disorders have had limited success. As an important mediator of environmental factors and regulators of circadian rhythms,the epigenetic system may hold the key to the etiology or pathology of psychiatric disorders,their subtypes or endophenotypes. Epigenomic regulation of the circadian system and the related changes have not been thoroughly explored in the context of neuropsychiatric disorders. We argue for systematic investigation of the circadian system,particularly epigenetic regulation,and its involvement in neuropsychiatric disorders to improve our understanding of human behavior and disease etiology.

关键词： epigenetics circadian rhythms neuropsychiatry

Theoretical, Numerical and Experimental Study on Synchronization of Three Identical Exciters in a Vibrating System

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 746-757页

作者： ZHANG Xueliang WEN Bangchun ZHAO chunyu School of Mechanical Engineering and Automation Northeastern University

The theory on synchronization of two exciters is more widely used in engineering, while that of more than two exciters is less considered. So it is of great significant to investigate synchronization of three exciters. Firstly by introducing the average method of modified small parameters, the dimensionless coupling equations(DCE) of three exciters are derived, which convert the problem of synchronization into that of existence and stability of zero solutions for the DCE and lead to the construction on criterions of synchronization and stability in the simplified form for three exciters. Then the synchronization criterion is discussed numerically, as well as the abilities of synchronization and stability, some results thereof indicate that the synchronization ability increases with the increase of the coupling moment among three exciters, but decreases with that of their phase differences. Finally, an experiment on synchronization with three exciters is carried out. Through the comparison and analysis of experimental data on phase differences among three exciters, responses of system, and phases of three exciters recorded by high-speed camera, the parameters of system satisfying the above two criterions can ensure the synchronous and stable operation of three exciters. As a result, the average method of modified small parameters can be used as a theoretical apparatus studying reasonably the synchronization mechanism of three exciters, it is also proved to be useful and feasible by numeric and experiment. The present research lays the foundation and guidance for the establishment of synchronization theory system with multi-exciter and engineering design.

关键词： synchronization vibrating system stability coupling dynamic double-equilibrium

GNAS mutations suppress cell invasion by activating MEG3 in growth hormone–secreting pituitary adenoma

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Oncology Research 2024年第6期32卷 1079-1091页

作者： CHAO TANG chunyu ZHONG JUNHAO ZHU FENG YUAN jin YANG YONG XU CHIYUAN MA Department of Neurosurgery Affiliated Jinling HospitalMedical School of Nanjing UniversityNanjing210002China Department of Neurosurgery Children’s Hospital of Nanjing Medical UniversityNanjing210019China Affiliated Eye Hospital Nanjing Medical UniversityNanjing210029China Department of Neurosurgery Jinling HospitalSouthern Medical UniversityNanjing210002China Department of Neurosurgery Jinling HospitalNanjing Medical UniversityNanjing210002China

Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive ***,the role of GNAS mutations in the invasiveness of GHPAs is *** mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing *** expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with ***3 was manipulated in GH3 cells using a lentiviral expression *** invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western ***,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and *** invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type ***,the invasiveness of mutant GNASexpressing GH3 cells ***3 is uniquely expressed at high levels in GHPAs harboring mutated ***,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell ***,GNAS mutations inhibit EMT in ***3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in *** data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway.

关键词： GHPAs GNAS mutation MEG3 β-catenin EMT

Drivers of tree demographic trade-offs in a temperate forest

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Forest Ecosystems 2022年第4期9卷 475-482页

作者： Jianghuan Qin chunyu Fan Yan Geng chunyu Zhang Xiuhai Zhao Lushuang Gao Research Center of Forest Management Engineering of State Forestry and Grassland Administration Beijing Forestry UniversityBeijing100083China

Background: The demographic trade-offs(i.e. growth and survival) play important roles in forest dynamics and they are driven by multiple factors, including species’ inherent life-history strategies(such as shade-tolerance and mycorrhizal type), neighborhood interactions(such as conspecific negative density dependence, CNDD), and abiotic environment pressures. Although studies found that CNDD occurred in tropical and temperate forest,attempts to identify how the variations in CNDD control their impacts on growth and survival remain debate. In the present study, we conducted an extensive field survey, and analyzed demographic rates from 24 co-occurring temperate tree species, in order to test the importance of CNDD in shaping the growth-survival ***: Our study found that density dependence and environmental filtering were strong predictors for individual growth-survival trade-offs, while they showed variations across shade-intolerant and ectomycorrhizal species, as well as saplings and juveniles with more negative CNDD. Species growth showed positive relationship with mortality. And our results also support the fact that CNDD drives species growth-survival trade-offs at the community level with environmental ***: Our study indicates that biotic interactions such as density dependence and environment filtering played an important role in growth-survival trade-offs, and confirmed that the Janzen-Connell hypothesis in temperate forest was associated with species life-history strategies. In addition, shade-tolerance, mycorrhizal type and life-stage of forest species responded differently to CNDD, thus providing insights regarding different community assembly mechanisms and their interactions. Therefore, it is important to take species survival with growth and species life-history strategies into account when focusing on forest dynamics.

关键词： Tree survival Density dependence Growth-survival trade-offs Life-history strategy Temperate forest

Dexterity Analysis for Omni-directional Wheeled Mobile Manipulator Based on Double Quaternion

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 585-593页

作者： DU Bin ZHAO jing SONG chunyu College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology

The unified analysis of omni-directional wheeled mobile manipulator(OWMM) through the dimensionally nonhomogeneous Jacobian matrix may lead to unreliable results. The existing researches focus on the integrated performance evaluation of OWMM, without taking the influence of velocity difference into consideration. This paper presents a new approach to formulate the dimensionally homogeneous Jacobian matrix and a new index for OWMM. First, the universal transformational matrix of the link coordinate frame is derived based on double quaternion. The degree of locomotion of a mobile platform and the degrees of manipulation of a manipulator are treated equally as the joints of a redundant composite robot. Then the integrated modeling of OWMM is established, and the non-dimensional Jacobian matrix is obtained from the above matrix. Next, by examining the concept of directional manipulability, a new index is proposed to evaluate the directional manipulability of OWMM along the specified task direction. Furthermore, for the same task and the time of simulation, the kinematic performance of the fixed base operation of the manipulator and the operation of OWMM are analyzed by numerical simulation. The results suggest that the proposed approach is equivalent to the method of traditional kinematic modeling, with the error of numerical solution being 10-7 , and the varying frequency of DMTR is higher than that of the condition number. This indicates that DMTR is more effective to reflect the variation of the task direction. The proposed method can be used to analyze the manipulating capability of OWMM, and has a simple structure and generality in the unified analysis of OWMM.

关键词： double quaternion homogeneous Jacobian mobile manipulator manipulability task direction

Constraining fast radio burst progenitors with gravitational lensing

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1390-1394页

作者： LI chunyu LI LiXin Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University

Fast Radio Bursts(FRBs)are new transient radio sources discovered *** of the angular resolution restriction in radio surveys,no optical counter part has been identified yet so it is hard to determine the progenitor of *** this paper we propose to use radio lensing survey to constrain FRB *** show that,different types of progenitors lead to different probabilities for a FRB to be gravitationally lensed by dark matter halos in foreground galaxies,since different type progenitors result in different redshift distributions of *** example,the redshift distribution of FRBs arising from double stars shifts toward lower redshift than of the FRBs arising from single stars,because double stars and single stars have different evolution *** detailed calculations,we predict that the FRB sample size for producing one lensing event varies significantly for different FRB progenitor *** argue that this fact can be used to distinguish different FRB models and also discuss the practical possibility of using lensing observation in radio surveys to constrain FRB progenitors.

关键词： star formation radio sources gravitational lenses and luminous arcs cosmology