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This paper is concerned with the sampled-position states based consensus of networked multi-agent systems with second-order dynamics, where agents are connected through communication channels subject to time-varying communication delays. Note that consensus in such systems cannot be reached if using only the current sampled-position states. This paper investigates the positive effects of time-varying communication delays on the consensus. For two cases, where a directed graph has a fixed or switching topology, several sufficient conditions on consensus are derived by using a discretized Lyapunov-Krasovskii functional method. Based on the obtained conditions, suitable control protocols can be devised through tuning two parameters. Finally, simulation shows that consensus can be achieved using sampled-position states if the time-varying communication delays are within a certain time interval with its lower bound strictly greater than zero. [ABSTRACT FROM AUTHOR]

Abstract Neuronal state estimation of neural networks is a fundamental issue, aiming at estimating neuronal states from contaminated neural measurement outputs. Inspired by extensive applications of neural networks, neuronal state estimation has become a hot research topic in the last decade. This paper presents an overview of neuronal state estimation of neural networks with time-varying delays. First, two kinds of state estimators are analyzed, and their differences are uncovered. Second, recent developments of a Lyapunov–Krasovskii functional method for performance analysis of estimation error systems are surveyed deeply, and some existing methods to design suitable state estimators are summarized with insightful understanding. Third, brief analysis of event-triggered neuronal state estimations of delayed neural networks is made. Finally, some challenging issues that need to be addressed in the near future are listed and briefly discussed. [ABSTRACT FROM AUTHOR]

This paper is concerned with output feedback stabilization of a networked control system in the discrete-time domain. First, a logical zero-order-hold is introduced to select the newest data packets to drive the plant, with which network-induced delays and data packet dropouts can be expressed explicitly. Second, an auxiliary vector-valued function is introduced to establish a novel finite-sum inequality, which can provide a tighter bound than some existing ones for some finite-sum term. Third, this finite-sum inequality is employed to formulate a stability criterion for the closed-loop system under consideration. It is proven that the stability criterion is of less conservatism than some existing ones reported in the literature. Fourth, a cone-complementary-linearization-based algorithm is presented to design suitable output feedback controllers. Finally, three examples are given to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper is concerned with the resilient and secure remote monitoring of a cyber-physical system of a discrete time-varying state-space form against attacks. The specific statistical characteristic, magnitude, occurring place and time of the attack signals are not required during the monitor design and attack detection procedures. First, an optimal ellipsoidal state prediction and estimation method is delicately developed in such a way that the recursively computed prediction ellipsoid and estimate ellipsoid can both guarantee the containment of the true system state at each time step regardless of the unknown but bounded input signal. It is expected that the two ellipsoids can resist certain attacks as the calculated state prediction and state estimate are sets in state-space rather than single pointwise vectors, thus potentially enhancing the resilience of the remote monitoring system. Second, a set-based evaluation mechanism in combination with a remedy measure are proposed to provide timely detection of certain attacks. Furthermore, a numerically efficient algorithm is established to achieve resilience and attack detection of the remote monitoring system. Finally, it is shown through several case studies on a water supply distribution system that the proposed methods can provide quantitative analysis and evaluation of the potential consequences of various attacks on the remote monitoring system. [ABSTRACT FROM AUTHOR]