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This paper studies the event‐triggered control of switched linear system with state‐dependent switching law. A dynamic term is introduced to the switching law to acclimatize the dynamic mode‐dependent event‐triggered controller. Besides, neither the switching law nor the controller needs continuous detection of the system states. Because of the event‐triggered and sampling behavior of the controller, asynchronous between the controller and the system modes are encountered. A new multiple Lyapunov functional is proposed to appropriately characterize the synchronous and asynchronous working modes of the system, and a sufficient exponential stability condition is obtained, which is applicable for the cases when some modes or all modes of the switched system are unstabilizable. Moreover, the event‐triggered control and switching law parameters are jointly designed using linear matrix inequalities. Numerical and comparison studies are offered to provide the validity and superiority of the result. [ABSTRACT FROM AUTHOR]

DC microgrid as a microscale power system has drawn growing attention for its various applications, which calls for good power quality, proper power sharing, and fast response property. However, the existing researches are not yet able to achieve the purpose in a predefined time. In this article, a new predefined-time secondary controller is proposed for DC microgrid to realize the objectives of both voltage regulation and current sharing among DGs within a predefined time. The controller is designed by employing a sign function and a $K^1$ function and by defining a new composite error, which does not need to sample the voltage of DC bus or the current of neighbors, but only the local current and voltage. The upper bound of the convergence time of both the voltage and current in the DC microgrid is just related to one parameter which can be predefined and is independent of initial error. The effectiveness of the proposed controller is verified by multiple simulations and experiments built on MATLAB/Simulink and a hardware-in-the-loop experimental platform. The conducted simulations and experiments include several typical scenarios together with a comparison, which illustrate the advantages of the proposed controller such as fast convergence rate and small overshoot. [ABSTRACT FROM AUTHOR]

This article studies the fault‐tolerant consensus issue of a class of nonlinear two‐time‐scale‐agent systems with heterogeneous sensor faults and external disturbances. First, the decentralized proportional integral (PI) observer for each agent is constructed to estimate the states and sensor faults simultaneously. Then, a distributed adaptive protocol based on the decentralized PI observer is designed to guarantee the consensus of the underlying systems. Some sufficient existence conditions are given in terms of linear matrix inequalities (LMIs) for the decentralized PI observer and the fault tolerant consensus protocol. Note that H∞$$ {H}_{\infty } $$ performance index is employed to attenuate the influence of sensor faults and disturbances on state estimation and the consensus of the underlying systems. Finally, the effectiveness and superiority of the proposed method are demonstrated by an application example and a numerical example. [ABSTRACT FROM AUTHOR]

This paper introduces a distributed compensation approach for the global optimization with separable objective functions and coupled constraints. By employing compensation variables, the global optimization problem can be solved without the information exchange of coupled constraints. The convergence analysis of the proposed algorithm is presented with the convergence condition through which a diminishing step-size with an upper bound can be determined. The convergence rate can be achieved at $O({lnT}/{\sqrt {T}})$. Moreover, the equilibrium of this algorithm is proved to converge at the optimal solution of the global optimization problem. The effectiveness and the practicability of the proposed algorithm is demonstrated by the parameter optimization problem in smart building. [ABSTRACT FROM AUTHOR]

This article investigates the current sharing and voltage regulation problem of a DC microgrid by a distributed supervisory control method. In the existing secondary control methods, current sharing feedback control loop and voltage regulation feedback control loop are linearly integrated to shift the droop equation. However, the linear combination of two loops may easily offset the control effect of each other, as the control dimension is less than the objective dimension. This fact motivates us to design a distributed supervisory secondary control (DSSC) scheme to achieve a more flexible configuring of each converter. The DSSC consists of two candidate controllers and a supervisor. The two controllers refer to current sharing configuring and DC bus voltage regulation respectively, and the supervisor is to orchestrate the switching between candidate controllers based on the system environment of DC microgrid. Under the proposed DSSC, each converter selects to configure the current sharing or regulates the DC bus voltage according to its need. Theoretical stability analysis is rigorously conducted. Finally, both simulation and experiment results are presented to demonstrate the effectiveness of DSSC. [ABSTRACT FROM AUTHOR]

This article develops a novel decentralized periodic energy trading framework for a pelagic islanded microgrid. Compared with situations of the microgrid connecting directly to the main grid and of the short-periodic energy trading system, in this article, we tackle the following challenges: the limitation of energy resources, the two types of end users (i.e., strategic users and normal users), the high uncertainty of renewable energy generations (REGs), and the nonconvexity of optimization problem. To overcome these four obstacles unavoidably existing in practice, we propose the models of user satisfaction with the priority power supply for strategic users. Robust optimization approach is adopted to address the uncertainty associated with the REGs. A nonconvex optimization problem derived from the game-theoretic approach and backward induction is solved via designing a decentralized bilevel iterative algorithm, then a Stackelberg equilibrium strategy is obtained, where the aggregator maximizes its revenue and each user minimizes its energy cost. Simulation results are provided to show the effectiveness and benefits of the proposed periodic energy trading framework for pelagic islanded microgrids. [ABSTRACT FROM AUTHOR]

In this paper, the global robust output regulation problem of a class of uncertain nonlinear systems is investigated by the event-triggered adaptive control law for the case of unknown control direction. The Nussbaum-type function-based technique is proposed to tackle the presence of unknown control direction. Then, by applying the adaptive control technique and the internal model principle, a new event-triggered adaptive control method is proposed. With the proposed corresponding event-triggered mechanism, the output regulation of the nonlinear systems can be realized regardless of the unknown control direction, meanwhile the Zeno behavior can be excluded. Finally, a numerical example is presented to verify the effectiveness of the proposed control law. [ABSTRACT FROM AUTHOR]

Summary: The article proposes several fault‐tolerant control (FTC) laws for singularly perturbed systems (SPS) with actuator faults and disturbances. One of the main challenges in this context is that the fast‐slow decomposition is not available for actuator faults and disturbances. In view of this, some conditions for the asymptotic stability of the closed‐loop dynamics are investigated by amending the composite Lyapunov approach. On top of this, a closed‐form expression of the upper bound of singular perturbation parameter (SPP) is provided. Moreover, we design several SPP‐independent composite FTC laws, which can be applied when this parameter is unknown. Finally, the chattering phenomenon is eliminated by using the continuous approximation technique. We also emphasize that, for linear SPSs, the FTC design can be formulated as a set of linear matrix inequalities, while the SPP upper bound can be obtained by solving a convex optimization problem. Two numerical examples are given to illustrate the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

Summary: This article studies the exponential stability of continuous‐time switched positive systems consisting of unstable subsystems. Different from the existing results, both stabilizing and destabilizing switching behaviors act in the switching sequences. By employing multiple composite copositive Lyapunov functions, sufficient condition is derived to ensure the exponential stability of the system, which evaluates the ratio of stabilizing switching behaviors to compensate the state divergence caused by either unstable subsystems or destabilizing switching behaviors. Simulations demonstrate the effectiveness of the result. [ABSTRACT FROM AUTHOR]

The pelagic islands usually include resource islands and load islands with electricity and natural gas transactions among them. Since they are apart from the main land, the finiteness of energy resources results in crucial need of developing efficient energy management framework for the pelagic islanded microgrid clusters (PIMGCs). In this paper, we introduce a novel multi-energy management framework for a PIMGC, where the operators on resource islands sell energy resources, while the aggregators and users on load islands dispatch and consume energy resources, respectively. The multi-scale energy management strategy is proposed, where the operators determine their daily optimal energy supply in a distributed collaborative way by adopting the primal-dual subgradient method, each aggregator determines its daily optimal energy demand and hourly optimal energy usage, and each user determines its hourly optimal energy consumption. A hierarchical day-ahead distributed algorithm is proposed to obtain the Nash equilibrium strategy, where the operators minimize their aggregate operational cost, each aggregator maximizes its revenue and each user maximizes its payoff. Simulation results are provided to show the effectiveness and benefits of the proposed multi-energy management framework for the PIMGCs. • A pelagic islanded microgrid cluster multi-energy management framework is proposed. • A hierarchical multi-scale bidirectional interaction mechanism is designed. • A tri-level day-ahead distributed algorithm is proposed. • Simulation results show the effectiveness and benefits of the proposed framework. [ABSTRACT FROM AUTHOR]

This paper investigates the stability problem of a single-bus DC microgrid with mixed grid-forming/grid-feeding converters and the constant impedance, constant current, and constant power (ZIP) loads. Considering the different output properties of grid-forming and grid-feeding converters, distributed secondary controllers with mixed V–I droop and I–V droop controllers are designed to achieve accurate bidirectional current sharing and voltage regulation. As few converters have access to the information of the common bus, an observer is designed for each local controller to estimate the bus voltage. Then, the observer state is used to generate voltage correction term in the feedback loop, which gets potential faster regulation compared with the existing approaches that use pinning gains. Based on the rank-one perturbation analysis, a stability criterion of DC microgrid is given for the case of ZI load, where global voltage regulation and current sharing are guaranteed. Then, the stability criterion is extended to the case of ZIP load, where local stability of the DC microgrid is guaranteed. Both numerical examples and experimental tests are given to verify the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the robust consensus problem of fractional-order multi-agent systems with input saturation and external disturbances is studied under a directed fixed topology. It’s the first time to consider the fractional-order agent subject to input saturation. When there exist input saturation and external disturbances simultaneously, by means of the Mittag–Leffler stability theorem and low gain feedback technique, a control protocol is presented to guarantee the robust consensus can be achieved. Moreover, as a special case, the leader-following consensus can be achieved when there only exists input saturation. Finally, the results are verified by several simulation examples. [ABSTRACT FROM AUTHOR]

This paper investigates the output formation-containment problem of interacted heterogeneous linear systems, where each heterogeneous system, whether the leader or the follower, has different dimensions and dynamics. Different from existing literature, discrete-time communication manner is deployed to reduce the communication consumption. By the impulsive control method, a distributed hybrid active controller is designed using the discrete-time information of neighbors. It achieves the output formation-containment of heterogeneous systems if two related conditions are satisfied, namely, local linear matrix inequalities (LMIs) and a bounded constraint on the average interacted interval. Moreover, the controller parameter design is further simplified by replacing the LMI condition with a Hurwitz condition, which can be easily guaranteed by solving a Riccati equation. Finally, a numerical example is provided to demonstrate the effectiveness of the theoretical result. [ABSTRACT FROM AUTHOR]

A class of persistent monitoring problems in one‐dimensional space with the aid of multi‐agent systems, which is formulated as an optimisation problem of minimising a novel performance metric is studied. The concept of the monitoring index is introduced in the performance metric to describe the importance of different targets in the space due to the requirements of the monitoring task. Based on a given class of moving trajectories, an optimal control approach is used to minimise the performance metric of monitoring space. After some model transformation, the infinitesimal perturbation analysis method is used to design the gradient‐based algorithm, aiming to find the optimal trajectories, where the monitoring index exhibits the effect on the monitoring time for different targets. Numerical simulations are represented to demonstrate the performance of the algorithm and reveal the effectiveness of the monitoring index. [ABSTRACT FROM AUTHOR]

As reported in the existing literature, wing attractors are confined to 1D -wing attractors, 2D -grid wing attractors. In this paper, we break this limitation and generate 3D -grid multi-wing chaotic attractors (GMWCAs). The 3D GMWCAs are produced via the following three steps: (1) applying rotation transformation to a double-wing Lorenz-like system to ensure that its saddle-focus equilibria with index 2 are located on the plane ; (2) extending the wing attractors of the transformed Lorenz-like system along the -axis to have mirror symmetry; (3) introducing stair switching functions to increase the number of saddle-focus equilibria with index 2 along the -axis and -axis. Furthermore, some basic dynamical properties of the 3D chaotic system, including equilibria, symmetry, dissipativity, Lyapunov exponents and bifurcation diagram, are investigated and a module-based unified circuit diagram is designed. The effectiveness of this approach is confirmed by both numerical simulations and electrical circuit experiment. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study the distributed optimization problem for continuous-time multi-agent systems with the existence and the interference of external disturbance, therein each agent is described as double-integrator dynamic. To reject the exogenous disturbance, the distributed algorithm is proposed for each agent based on the internal model principle. The proposed algorithm only utilizes the position information of each agent from its neighbors subject to the undirected graph, which can reduce communication costs and energy consumptions in applications. Moreover, the algorithm only needs the cost functions of the agent itself, which can greatly protect the privacy of other agents. The optimal solution of the problem is thus obtained with the design of Lyapunov function and the help of convex analysis, LaSallel’s Invariance Principle. Finally, two numerical simulation examples and the comparison of proposed algorithm with other previous research are presented to illustrate the persuasive effectiveness of the theoretical result. [ABSTRACT FROM AUTHOR]

This paper addresses the modulus consensus in a network of singularly perturbed systems, all of which own multi-time scales characteristics. The interactions among the agents are collaborative and antagonistic interactions, and it can been modelled by a signed directed graph. Also, the effect of time-varying delay has been taken into account when modelling the agent dynamics. Based on singularly perturbed decomposition method, Kronecker product technique and the comparison principle, several sufficient conditions are presented under which networked singularly perturbed time-varying delay systems with collaborative and antagonistic interactions achieve modulus consensus. Moreover, the upper bound of singular perturbation parameter is deduced explicitly. Two simulation examples are presented to illustrate the validity of the proposed results. [ABSTRACT FROM PUBLISHER]

In this study, the distributed optimisation problem is investigated by using the framework of second‐order multi‐agent systems (MASs) over a directed communication topology. A distributed algorithm is proposed for the MASs to seek the solution of the optimisation problem. The proposed algorithm contains two layers, the cooperative compensator and the local optimiser, where the former layer is to compensate the cooperative errors and the latter will lead the agents to the optimal solution. In the algorithm, each agent only uses the position information from its neighbours in the presence of delay. By utilising the Lyapunov–Krasovskii functional, delay‐dependent conditions are derived for the slowly‐varying and fast‐varying delays, respectively, to guarantee the algorithm converges to the optimal solution. Furthermore, a criterion on solving the optimisation problem through the MASs with discrete‐time communication is also proposed directly from the result of the fast‐varying delay. Finally, a numerical simulation example is presented to illustrate the persuasive effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the distributed hierarchical control design is investigated for cooperations of heterogeneous linear systems subjected to the switching networks, where each subgraph of switching networks is allowed to be disconnected. Each heterogeneous system contains uncontrollable states and evolves in different dimension with different dynamics. The hierarchical control framework proposed in this paper consists of distributed hierarchical controllers, which contain the upper-layers dealing with the communication topologies and the lower-layers dealing with the heterogeneity of the systems. Under the framework, the cooperation problem of heterogeneous linear systems is decoupled into a cooperation problem of homogeneous virtual systems in the upper-layer and tracking problems of each single systems in the lower-layer. These two layers are designed based on the optimal control method and the output regulation method, respectively. Under the hierarchical control framework, the leader-following consensus of heterogeneous linear systems is achieved and the result is extended to the formation control problem. Finally, numerical examples are provided to demonstrate the effectiveness of the theoretical results. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study investigates the adaptive fuzzy fault‐tolerant control (FTC) problem for a class of non‐linear multi‐input multi‐output systems with interconnections among subsystems and external unknown disturbance. The introduced multiple coupling terms have unknown non‐linear forms relying on the system outputs and the corresponding subsystems, which cause that the system is no longer pure‐feedback. Moreover, the considered actuator failures have a lock‐in‐place type and a type of loss of effectiveness. To solve the problem of actuator faults, compensative adaptive laws are constructed by taking advantages of the global fuzzy approximation property and a novel backstepping design procedure. According to the Lyapunov stability theorem, it is shown that all the signals in the closed‐loop system are bounded and the outputs can converge to a giving compact set. In addition, simulation examples are presented to validate the effectiveness of the proposed adaptive fuzzy FTC protocol. Compared with previous researches on non‐linear systems with unknown coupling terms, the proposed adaptive fuzzy FTC approach is more general, which may provide promising prospects of implementing in practical industrial systems. [ABSTRACT FROM AUTHOR]

In this paper, the input-to-state stability (ISS) problem of switched linear system with unstabilizable modes is investigated under denial-of-service (DoS) attacks and external disturbance. In contrast to earlier results which consider only stabilizable modes and usually impose certain constraints on the switching behavior and the DoS attacks, the switched system with unstabilizable modes is studied and a flexible description is proposed to specify the unstabilizable modes. Besides, a more general situation is considered that it allows switching during the active period of DoS attack and the attacks can take place arbitrarily independent of switching. Thus, it leads to a better description of switched system under DoS attacks and a more general result. Moreover, under the sampling scheme and DoS attacks, the asynchronous problem arises. Despite these added complications, a sufficient condition concerning DoS attacks frequency and duration is derived to ensure the ISS of the system under DoS attacks, and the result reveals the trade-off between the average time proportion of unstabilizable modes and the resilience of the system against DoS attacks. Finally, a numerical example and a comparative study are given to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this letter, a class of complex dynamical networks with additive stochastic time-varying delays is investigated. Two kinds of delays in complex dynamical networks are taken into consideration, one is called the nodes-induced delay in this paper, and the other is the network-induced delay. Both of the delays are assumed to obey different stochastic distributions. By utilising a novel Lyapunov–Krasovskii functional and stochastic analysis techniques, a sufficient criterion is obtained in the form of linear matrix inequalities to ensure the synchronisation of the complex dynamical networks. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]

This paper addresses the robust reliable guaranteed cost control problem of positive interval systems with multiple time delays and actuator failure for a given quadratic cost function. Through constructing a Lyapunov–Krasovskii functional, a sufficient condition for the existence of robust reliable guaranteed cost controllers is established such that the closed-loop system is positive and asymptotically stable, and the cost function is guaranteed to be no more than a certain upper bound. Based on the linear matrix inequality method, a criterion for the design of robust reliable guaranteed cost controllers is derived which can tolerate all admissible uncertainties as well as actuator failure. Moreover, a convex optimisation problem with linear matrix inequality constraints is formulated to design the optimal robust reliable guaranteed cost controller which minimises the upper bound of the closed-loop system cost. A numerical example is given to show the effectiveness of the proposed methods. [ABSTRACT FROM PUBLISHER]

This paper addresses the multistability problem of discrete-time delayed Cohen–Grossberg neural networks (DDCGNNs) with second-order synaptic connectivity. For the neural networks with nondecreasing saturated activation functions possessing 2 corner points, based on the partition space method and reduction ad absurdum, several sufficient conditions are derived to ensure that n -neuron second-order DDCGNNs can have 2 n locally exponentially stable equilibrium points. Then, the analyses are extended to nondecreasing saturated activation functions with 2 r corner points and some sufficient conditions are given to guarantee that the n -neuron DDCGNNs can have ( r + 1 ) n locally exponentially stable equilibrium points. Moreover, some conditions are obtained to ensure the existence of locally exponentially stable equilibrium point in a predesigned region. Finally, three examples are carried out to show the effectiveness of the proposed criteria. [ABSTRACT FROM AUTHOR]

This paper has investigated the impact of the incident titanium ion energy on the surface structure formation mechanism and the film properties during the amorphous TiO 2 thin film deposition process with the molecular dynamics simulation method. The results show that the increase of film density and the reduction of the surface roughness happen when the energy of incident titanium ions is increased. It is also found that the film growth mode is the Volmer-Weber (island) growth mode under the influence of the surface potential. The effect of surface potential is more significant if the incident ions energy becomes smaller. That will make the Volmer-Weber (island) growth mode promoted and the surface roughness of the deposited films become larger. Conversely, the Volmer-Weber growth mode is inhibited when the incident ion energy is higher. It will be conducive to the formation of more smooth film surface. [ABSTRACT FROM AUTHOR]

The paper studies the structural, thermo- and electronic properties of the silanone group (SG, oxygen double-bond) as bulk defect of amorphous SiO 2 (a-SiO 2 ), whose supercell consists of 108 atoms, and the molecular dynamics and first principle calculations are used. The results theoretically prove the existence and good thermo-stability of SG as bulk defect in a-SiO 2 . Besides, the electronic density of states (DOS) and orbital-resolved partial DOS (PDOS) are studied as well. The results show that new electronic state distribution in the band gap of a-SiO 2 is found, as well as reduced width of the band gap, which are produced by the SG defect. [ABSTRACT FROM AUTHOR]

This study investigates the consensus problem of second‐order multi‐agent systems (MASs) via impulsive control using position‐only information with communication delays. The communication delays between any two distinct agents are different which can be larger than one impulsive period. A distributed impulsive consensus protocol is designed, in which only the delayed sampled relative positions to neighbours and the relative position to the last sampling state are utilised. By introducing some virtual subgraphs and performing three steps of model transformation, the consensus problem of original continuous‐time system is converted to the stability problem of a discrete‐time expanded error system. Some necessary and sufficient criteria are derived to grantee the dynamic average‐consensus of the MAS. Furthermore, a special case, that is, the delays less than one impulsive period, is discussed, and the bounds of impulsive periods for the dynamic average‐consensus are obtained in explicit expressions for both the undirected and directed communication graphs, respectively. Two numerical simulation examples are given to illustrate the effectiveness of theoretical results. [ABSTRACT FROM AUTHOR]

This paper addresses the stability problem of switched positive linear systems with stable and unstable subsystems. Based on a multiple linear copositive Lyapunov function, and by using the average dwell time approach, some sufficient stability criteria of global uniform exponential stability are established in both the continuous-time and the discrete-time cases, respectively. Finally, some numerical examples are given to show the effectiveness of the proposed results. [ABSTRACT FROM PUBLISHER]

In this study, the consensus problem for a class of second‐order multi‐agent systems (MASs) with Markovian characterisations is investigated. The stochastic switching topology and the random communication delay are dominated by two mutually independent Markov chains. The communication delay exists in the switching signal as well as the position information exchanges in the authors' work. A novel consensus protocol is presented without using the neighbours' velocity information. By performing three steps of model transformation and introducing a mapping for the two independent Markov chains, the original system is converted into an expanded analogous error system with two Markovian jumping parameters. A necessary and sufficient criterion for the mean square consensus of the Markovian jump second‐order MASs with random communication delay is derived. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the theoretical result. [ABSTRACT FROM AUTHOR]

In this paper, the formation tracking problem for the second-order multi-agent system with and without input delay are investigated, respectively. The objective is to design the formation tracking algorithm such that a certain follower follows the trajectory of the leader while also maintains a certain desired geometric formation with other agents simultaneously. The impulsive algorithms are designed by using only the relative position information of the neighbors for both the cases with and without the input delay. By using properties of the Laplacian matrix and combining the stability theory of impulsive systems, necessary and sufficient conditions are derived to achieve the formation tracking of the second-order multi-agent system with and without the input delay, respectively. The numerical examples are given to illustrate the effectiveness of our theoretical results. [ABSTRACT FROM AUTHOR]

This study addresses the problem of exponential stability for a class of impulsive positive systems with mixed time‐varying delays. A delayed impulsive positive system model is introduced for the first time and a necessary and sufficient condition guaranteeing the positivity of this kind of system is proposed. By using a copositive Lyapunov–Krasovskii functional and the average impulsive interval method, a sufficient criterion of global exponential stability for delayed impulsive positive systems is established in terms of linear programming problems. A numerical example is given to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper presents models for both the continuous-time and discrete-time directed complex dynamical networks (CDNs) with random packet loss, respectively. The packet loss may take place in the communication between every two neighbor nodes. The exponential mean-square stability and the exponential mean-square synchronization for both the continuous-time and discrete-time CDNs with random packet loss are investigated, respectively, by defining the packet loss probability matrix. In addition, two special cases, the CDN with synchronous packet loss and the CDN with node-dependent packet loss, are discussed. Numerical examples are provided for illustrations. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, we used a phage display technique to screen differentially expressed proteins from zebrafish post-gastrula embryos. With a subtractive screening approach, 6 types of single-chain Fv fragments (scFvs) were screened out from an scFv antibody phage display library by biopanning against zebrafish embryonic homogenate. Four scFv fragments (scFv1, scFv3, scFv4 and scFv6) showed significantly stronger binding to the tailbud embryos than to the 30%-epiboly embryos. A T7 phage display cDNA library was constructed from zebrafish tailbud embryos and used to identify the antigens potentially recognized by scFv1, which showed the highest frequency and strongest binding against the tailbud embryos. We acquired 4 candidate epitopes using scFv1 and the corresponding genes showed significantly higher expression levels at tailbud stage than at 30%-epiboly. The most potent epitope of scFv1 was the clone scFv1-2, which showed strong homology to zebrafish myristoylated alanine-rich C-kinase substrate b (Marcksb). Western blot analysis confirmed the high expression of marcksb in the post-gastrula embryos, and the endogenous expression of Marcksb was interfered by injection of scFv1. Zebrafish marcksb showed dynamic expression patterns during embryonic development. Knockdown of marcksb strongly affected gastrulation movements. Moreover, we revealed that zebrafish marcksb is required for cell membrane protrusion and F-actin alignment. Thus, our study uncovered 4 types of scFvs binding to zebrafish post-gastrula embryos, and the epitope of scFv1 was found to be required for normal gastrulation of zebrafish. To our knowledge, this was the first attempt to combine phage display technique with the embryonic and developmental study of vertebrates, and we were able to identify zebrafish marcksb that was required for gastrulation. [Copyright &y& Elsevier]

SUMMARY In this paper, a complex switched network (CSN) with parametric uncertainties and two types of time-varying delays is presented. The CSN contains switching behaviors on both its nodes and the network topology. Different from those CSNs studied in the literatures, the switching mode dominating the nodes systems is independent with that dominating the network topology. The two types of time-varying delays are the system delay in the node and the coupling delay between nodes and they have different values. The inherent synchronization properties of the CSN were investigated not subject to any controllers, and sufficient conditions for the global robust exponential synchronizations are obtained by defining a piecewise Lyapunov-Krasovskii function. Both the case with known derivative of delays and the case with unknown or nonexistent derivative of delays are investigated. Two special cases, i.e. the network without coupling delay and the network without switching behaviors and coupling delay, are studied. Illustrated examples are presented to show the effectiveness of the proposed methods. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, synchronization of continuous dynamical networks with discrete-time communications is studied. Though the dynamical behavior of each node is continuous-time, the communications between every two different nodes are discrete-time, i.e., they are active only at some discrete time instants. Moreover, the communication intervals between every two communication instants can be uncertain and variable. By choosing a piecewise Lyapunov–Krasovskii functional to govern the characteristics of the discrete communication instants and by utilizing a convex combination technique, a synchronization criterion is derived in terms of linear matrix inequalities with an upper bound for the communication intervals obtained. The results extend and improve upon earlier work. Simulation results show the effectiveness of the proposed communication scheme. Some relationships between the allowable upper bound of communication intervals and the coupling strength of the network are illustrated through simulations on a fully connected network, a star-like network, and a nearest neighbor network. [ABSTRACT FROM PUBLISHER]

Abstract: This paper presents a general impulsively-coupled complex switched network (ICCSN) model with parametric uncertainties and multiple Time-varying Delays in both the linear and nonlinear terms. The model is more general than those in the literature in that it contains switching behaviors on nodes and impulsive effects in the whole topology. Robust synchronization of ICCSNs with parametric uncertainties and time-varying delays is investigated. Based on the Lyapunov stability theory, delay-independent synchronization conditions for ICCSNs with uncertainties and delays are obtained. In addition, we consider five special synchronization cases: ICCSNs with delays in both the linear and nonlinear terms, ICCSNs with parametric uncertainties and delays either in the linear or in the nonlinear term, ICCSNs without switching behaviors but with parametric uncertainties and delays, and impulsively-switched-coupled complex switched network with uncertainties and delays. A systematic-design procedure is presented, and a numerical example is carried out to demonstrate the effectiveness of the proposed synchronization strategy. A comparative study of the maximum impulsive intervals for synchronization is presented for all special cases. [Copyright &y& Elsevier]

Abstract: In this paper, the synchronization of complex dynamical networks (CDNs) under ‘successful’ but recoverable attacks is studied by utilizing the framework of switching systems. ‘Successful’ attacks refer to a class of attacks that break a network into a group of isolated clusters. Recoverable attacks refer to a class of attacks that the network can recover from after a period of time. To facilitate the investigation of the synchronization of a CDN under ‘successful’ but recoverable attacks, the attack frequency and the average recovering time are introduced. By using a piecewise Lyapunov function, the upper bounds of the attack frequency and the average recovering time are obtained to ensure that the whole network can achieve global synchronization under attacks. [Copyright &y& Elsevier]

Impulsive synchronization of chaotic systems is an attractive topic and a number of interesting results have been obtained in recent years. However, all of these results on impulsive synchronization need to employ full states of the system to achieve the desired objectives. In this paper, impulsive synchronization that needs only part of system states is studied for a class of nonlinear system. Typical chaotic systems, such as Lorenz system, Chen's system, and a 4D hyperchaotic system, are taken as examples. A new scheme is proposed to select the impulsive intervals. After some theoretical analysis, simulation results show the effectiveness of the proposed synchronization scheme. [ABSTRACT FROM AUTHOR]