Tongren College

Tongren, China

Tongren College

Tongren, China
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Zhang H.,Nanjing University of Science and Technology | Ji H.,Jiangnan University | Ye Z.,Chongqing University of Technology | Senping T.,South China University of Technology | And 3 more authors.
Nonlinear Analysis: Hybrid Systems | Year: 2017

In this paper, the impulsive consensus problem for multi-agent systems is investigated. The purpose of this paper is to provide a valid consensus protocol that overcomes the difficulty caused by stochastically switching structures via impulsive control. Some sufficient conditions of almost sure consensus are proposed when the switching structures are the independent process or the Markov process. It is shown that the sum-zero rows of matrix play a key role in achieving group consensus. Furthermore, simulation examples are provided to illustrate and visualize the effectiveness of these results. © 2017 Elsevier Ltd


Zhang H.,Shanghai University | Zhang H.,Tongren College | Zhou J.,Shanghai University
Systems and Control Letters | Year: 2012

This paper is concerned with the synchronization problem of sampled-data coupled harmonic oscillators with control inputs missing. A distributed algorithm for synchronization in undirected networks of coupled harmonic oscillators is proposed based on the sampled-data measurement with controller failures. Some generic criteria for such algorithm over, respectively, undirected fixed and switching network topologies are derived analytically. Compared with some existing works, a distinctive feature of this work is to solve synchronization problem in undirected networks even if each oscillator intermittently exchanges the velocity information with its neighbors in terms of sampled-data setting only at discrete moments. Subsequently, numerical examples illustrate and visualize the effectiveness and feasibility of the theoretical results. © 2012 Elsevier B.V. All rights reserved.


Wu Q.,Shanghai University of Electric Power | Wu Q.,Shanghai University | Zhou J.,Shanghai University | Zhang H.,Shanghai University | And 2 more authors.
International Journal of Systems Science | Year: 2013

In this article, we propose a distributed δ-consensus protocol in directed networks of dynamic agents having communication delays. The δ-consensus protocol is an average consensus protocol where agents exchange the information with their neighbours at some discontinuous moments. We provide convergence analysis for such consensus algorithm under stochastic switching communication graphs, and then present some generic criteria for solving the average consensus problem. We also show that directed delayed networks of dynamic agents can achieve average consensus even when each agent in the networks intermittently exchanges the information with its neighbours only at some discrete moments. Subsequently, a typical numerical example illustrates and visualises the effectiveness and feasibility of the theoretical results. © 2013 Taylor & Francis.


Ma M.,Zhangzhou Normal University | Ma M.,Shanghai University | Zhang H.,Chongqing University of Technology | Zhang H.,Tongren College | And 2 more authors.
Kybernetika | Year: 2013

This paper is concerned with impulsive practical synchronization in a class of n-dimensional nonautonomous dynamical systems with parameter mismatch. Some simple yet general algebraic synchronization criteria are derived based on the developed practical stability theory on impulsive dynamical systems. A distinctive feature of this work is that the impulsive control strategy is used to make n-dimensional nonautonomous dynamical systems with parameter mismatch achieve practical synchronization, where the parameter mismatch likewise exist in both system parameters and external excitation ones, and the synchronization error bound can be estimated by an analytical expression. Subsequently, the obtained results are applied to a typical gyrostat system, and numerical simulations demonstrate the effectiveness of the criteria and the robustness of the control technique.


Zhang H.,Shanghai University | Zhang H.,Chongqing University of Technology | Zhang H.,Tongren College | Zhou J.,Shanghai University
IET Control Theory and Applications | Year: 2013

In this study, a distributed consensus protocol is proposed for second-order multi-agent systems having input time delays. A distinctive feature of the algorithm is to address consensus problems for second-order multi-agent systems with local instantaneous interaction, where each agent can only exchange the position information with its neighbours at a series of discrete-time instants and update its velocity state in the form of abrupt jumps setting. The authors also establish the consensus conditions over fixed and switching network topologies, respectively. It is shown that consensus can be exponentially reached if the interaction graph of the system is connected and the interaction intervals are less than a given threshold value. Subsequently, numerical simulations are given to illustrate and visualise the effectiveness and feasibility of the theoretical results. © The Institution of Engineering and Technology 2013.


Zhou J.,Shanghai University | Zhang H.,Shanghai University | Zhang H.,Tongren College | Xiang L.,Shanghai University | Wu Q.,Shanghai University of Electric Power
Automatica | Year: 2012

In this brief we propose a distributed algorithm for synchronization of coupled harmonic oscillators with local instantaneous interaction. We provide convergence analysis for such algorithm without and with a leader over fixed and switching undirected network topologies, respectively. We also establish the conditions by which the coupled harmonic oscillators achieve synchronized oscillatory motions under instantaneous network connectivity. It is shown that the coupled harmonic oscillators can be synchronized even each oscillator instantaneously exchanges the velocity information with its neighbors only at discrete moments. Subsequently, numerical examples illustrate and visualize the effectiveness and feasibility of the theoretical results. © 2012 Elsevier Ltd. All rights reserved.


Cai L.,Shanghai University | Zhou J.,Shanghai University | Zhang H.,Shanghai University | Zhang H.,Tongren College
Proceedings - 4th International Workshop on Chaos-Fractals Theories and Applications, IWCFTA 2011 | Year: 2011

This present paper addresses chaos synchronization of the well-known electro-mechanical gyrostat systems via time-delay feedback control. Some simple yet generic criteria for chaos synchronization of coupled electro-mechanical gyrostat systems are derived analytically. To this end, numerical simulations are given to verify the effectiveness of the proposed control methodology. © 2011 IEEE.


Zhang H.,Shanghai University | Zhang H.,Tongren College | Zhou J.,Shanghai University | Liu Z.,Shanghai University
Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME | Year: 2012

The primary objective of this paper is to propose a distributed synchronization algorithm in undirected networks of coupled harmonic oscillators having communication delays under local instantaneous interaction. Some generic criteria on exponential convergence for such algorithm over, respectively, undirected fixed and switching network topologies are derived analytically. Different from the existing pure continuous or discrete-time algorithms, a distinctive feature of this work is to solve synchronization problem in undirected networks even if each oscillator instantaneously exchanges the information of the velocity with its neighbors only at some discrete moments. It is shown that the networked harmonic oscillators can be synchronized under instantaneous network connectivity. Subsequently, numerical examples illustrate and visualize the effectiveness and feasibility of the theoretical results. © 2012 American Society of Mechanical Engineers.


Ran X.,Guizhou University | Zhang G.,Guizhou University | Li S.,Guizhou University | Wang J.,Guizhou University | Wang J.,Tongren College
African Health Sciences | Year: 2017

Background: Camptothecin (CPT) is a potent drug against cancers, originally from plants. The endophytic fungi could produce the secondary metabolite same as the host and is used as medicine. Objectives:The aim of this paper was to investigate an endophytic fungal CPT with anti-neoplastic activity. Methods: Endophytic fungi were isolated from Camptotheca acuminata in China. CPT from strain S-019 was characterized by TLC, HPLC and EI-MS analysis. Anti-tumor activity of fungal CPT was detected by MTT and fluorescent dye methods using Vero and PC-3 cells. Results: A total of 94 endophytic fungi strains were isolated from tissues of C. acuminata and 16 fungi strains displayed cytotoxic activity on Vero or PC3 cells. Of which, the fungal strain S-019, classified as Fusarium solani, displayed impressive cytotoxic activity on cancer cells and was found to produce CPT by analysis of TLC, HPLC and EI-MS methods. Bioassay studies confirmed that the fungi CPT had potent cytotoxicity on Vero cells and induced apoptosis of Vero cells. Conclusion: The endophytic fungi from camptotheca trees are a reliable source for natural anticancer compounds. The endophytic fungi could produce CPT same as plant. The fungal CPT exhibited effective activity at inhibiting cell growth and inducing apoptosis on Vero cells. © 2017, Makerere University, Medical School. All rights reserved.


Gong J.,Tongren College | Wu C.-M.,Zhejiang University
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2010

CHOKe is an algorithm of fair approximation of the stateless and active queue management. The CHOKe hit, whose effectiveness and the force of punishing non-response flows are the crucial factors to enhance the fairness algorithm, is used to approximately identify and punish non-response flows. In this paper a new algorithm, S-CHOKe, which enhances the fairness of the CHOKe algorithm, not only replace the CHOKe hit with sampling CHOKe hit to improve the effectiveness of CHOKe hit, but also use Queue hit to adaptively determine the number of packet loss so to moderately punish non-response flows. Simulation results show that S-CHOKe, which is able to adapt to changes in flow quantity, is effective and fair.

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