http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Zhengguang Ma,Zengqiang Chen,Zhong-Xin Liu 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.6
In this paper, the consensus problems of multiple agents with continuous-time single-integrator dynamicsare studied, where each agent can obtain the position data of its neighboring agents at discrete-time points by usingthe periodic sampling technology and zero-order hold circuit. The smart leader is introduced, which can adjust theinteraction strength between itself and the target point according to the state errors between itself and its neighboringfollowers. The modified leader-following consensus problem is defined as the leader-following consensus problemwhen the smart leader is adopted. Different leader-following consensus protocols are obtained for the multi-agentsystems with or without sampling delays. The theoretical results, which are analysed with Lyapunov stability theory,can decrease the tracking error of the system, especially for the multi-agent systems with disturbance generated byactuator faults. Some simulation examples and real experiments are presented for illustration.
Xiangquan Li,Zhengguang Xu,Cheng Han,Jiarui Cui 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.11
The ability to deal with the system disturbance and/or data dropout is often referred to as the robustness of model-free or data-driven control theory. This paper addresses a novel pattern-moving-based partial-form dynamic linearization intermittent model-free adaptive control scheme for a class of nonlinear discrete-time systems with disturbance and random measurement data dropout. Furthermore, the bounded convergence of the tracking error of the closed-loop system is proved by the statistical approach with contraction mapping principle. The basic idea is to consider the pattern-moving-based partial-form dynamic linearization model-free adaptive control method under the condition of missing data which may be caused by network failure, failing sensor or actuator. The designed scheme mainly includes an improved intermittent tracking control law, an intermittent classification-metric bias estimation algorithm and a modified intermittent pseudo gradient vector estimation algorithm. The bounded convergence and effectiveness of the proposed scheme are demonstrated by both the rigorous mathematical inference and two numerical examples.
Xiangquan Li,Zhengguang Xu,Yanrong Lu,Jiarui Cui,Lixin Zhang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.10
This paper addresses a pattern-moving-based modified model free adaptive control (PMFAC) scheme and illustrates the convergence of its tracking error for a class of nonlinear systems with unknown model and multi-threshold quantized observations. The basic idea is to consider the system’s quantization error as an external disturbance and an improved performance index function of control law is proposed from the perspective of twoplayer zero-sum game (TP-ZSG) based on the existed MFAC algorithms. The PMFAC scheme is established which mainly includes an improved tracking control law and a pseudo-partial derivative (PPD) estimation algorithm. Under certain conditions, the bounded convergence of system tracking error and the stability of PMFAC system with quantization errors can be guaranteed. The theoretical results are demonstrated by two numerical examples.
An efficient approach to structural static reanalysis with added support constraints
Haifeng Liu,Baisheng Wu,Zhengguang Li 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.43 No.3
Structural reanalysis is frequently used to reduce the computational cost during the process of design or optimization. The supports can be regarded as the design variables in various types of structural optimization problems. The location, number, and type of supports may be varied in order to yield a more effective design. The paper is focused on structural static reanalysis problem with added supports where some node displacements along axes of the global coordinate system are specified. A new approach is proposed and exact solutions can be provided by the approach. Thus, it belongs to the direct reanalysis methods. The information from the initial analysis has been fully exploited. Numerical examples show that the exact results can be achieved and the computational time can be significantly reduced by the proposed method.
An efficient approach to structural static reanalysis with added support constraints
Liu, Haifeng,Wu, Baisheng,Li, Zhengguang Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.43 No.3
Structural reanalysis is frequently used to reduce the computational cost during the process of design or optimization. The supports can be regarded as the design variables in various types of structural optimization problems. The location, number, and type of supports may be varied in order to yield a more effective design. The paper is focused on structural static reanalysis problem with added supports where some node displacements along axes of the global coordinate system are specified. A new approach is proposed and exact solutions can be provided by the approach. Thus, it belongs to the direct reanalysis methods. The information from the initial analysis has been fully exploited. Numerical examples show that the exact results can be achieved and the computational time can be significantly reduced by the proposed method.
Wang Jiangfei,Yuan Lihua,Zhu Zhengguang,Yuan Mingyuan 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.11
Aiming at infrared thermal images with different buried depth defects, we study a variety of image segmentation algorithms based on the threshold to develop global search ability and the ability to find the defect area accurately. Firstly, the iterative thresholding method, the maximum entropy method, the minimum error method, the Ostu method and the minimum skewness method are applied to image segmentation of the same infrared thermal image. The study shows that the maximum entropy method and the minimum error method have strong global search capability and can simultaneously extract defects at different depths. However none of these five methods can accurately calculate the defect area at different depths. In order to solve this problem, we put forward a strategy of \divide and conquer". The infrared thermal image is divided into several local thermal maps, with each map containing only one defect, and the defect area is calculated after local image processing of the different buried defects one by one. The results show that, under the \divide and conquer" strategy, the iterative threshold method and the Ostu method have the advantage of high precision and can accurately extract the area of different defects at different depths, with an error of less than 5%.
Identification and confirmation of 14-3-3 ζ as a novel target of ginsenosides in brain tissues
Feiyan Chen,Lin Chen,Weifeng Liang,Zhengguang Zhang,Jiao Li,Wan Zheng,Zhu Zhu,Jiapeng Zhu,Yunan Zhao 고려인삼학회 2021 Journal of Ginseng Research Vol.45 No.4
Background: Ginseng can help regulate brain excitability, promote learning and memory, and resist cerebral ischemia in the central nervous system. Ginsenosides are the major effective compounds of Ginseng, but their protein targets in the brain have not been determined. Methods: We screened proteins that interact with the main components of ginseng (ginsenosides) by affinity chromatography and identified the 14-3-3 ζ protein as a potential target of ginsenosides in brain tissues. Results: Biolayer interferometry (BLI) analysis showed that 20(S)-protopanaxadiol (PPD), a ginseng saponin metabolite, exhibited the highest direct interaction to the 14-3-3 ζ protein. Subsequently, BLI kinetics analysis and isothermal titration calorimetry (ITC) assay showed that PPD specifically bound to the 14-3-3 ζ protein. The cocrystal structure of the 14-3-3 ζ protein-PPD complex showed that the main interactions occurred between the residues R56, R127, and Y128 of the 14-3-3 ζ protein and a portion of PPD. Moreover, mutating any of the above residues resulted in a significant decrease of affinity between PPD and the 14-3-3 ζ protein. Conclusion: Our results indicate the 14-3-3 ζ protein is the target of PPD, a ginsenoside metabolite. Crystallographic and mutagenesis studies suggest a direct interaction between PPD and the 14-3-3 ζ protein. This finding can help in the development of small-molecular compounds that bind to the 14-3-3 ζ protein on the basis of the structure of dammarane-type triterpenoid.
Yanwei Li,Jinhuan Yao,Shengkui Zhong,Zhengguang Zou 한국물리학회 2011 Current Applied Physics Vol.11 No.6
The effect of molecular orientation on the electron transport behavior of single porphyrin sandwiched between two gold (111) electrodes is investigated by density functional theory calculations combined with non-equilibrium Green’s function method. The results show that the porphyrin with parallel connection to gold (111) electrodes is more conductive than the porphyrin with diagonal connection to gold (111) electrodes. The mechanism of the difference of electron transport for these two molecular junctions is analyzed from the transmission spectra and the molecular projected self-consistent Hamiltonian states. It is found that the intrinsic nature of the molecule, such as the π-conjugated framework and the strength of molecule―electrode coupling, are the essential reason for generating this difference of electron transport for the two molecular systems.
You Li,Mulan Tang,Shuxin Xu,Shuchao Zhang,Yuxin Zhai,Jiarong Yin,Zhengguang Zou 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.114 No.-
The NASICON-type solid electrolyte structure of Li1.3Al0.3Ti1.7(PO4)3 (LATP) exhibits good electrochemicalperformance and thermal stability, and has been promising as a solid electrolyte. Here, a stable goodstabilityLATP precursor spinning solution was prepared using the sol–gel method for the first time. A linearLATP solid electrolyte with an oriented ordered structure was obtained using improved electrostaticspinning equipment. The sintering process regime of the LATP-ordered construction was determined. Theionic conductivity of the prepared LATP-PEO/LiClO4-PEG composite solid-state electrolyte with anordered structure was as high as 2.05 10-4 Scm1 at room temperature (25 C), one order of magnitudehigher than the ionic conductivity of the LATP composite solid-state electrolyte reported so far. Organicsolid-state electrolytes to protect LATP-ordered structured solid-state electrolytes yield excellent electrochemicalstability in lithium-metal batteries.