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The relationship between China and Australia has maintained a trend of fluctuating development for a long period since the establishment of diplomatic ties. However, around 2017, Australia gradually adopted negative policies towards China, and the relationship between the two countries cooled down rapidly, with no obvious easing trend. Based on the Multiple Stream Framework, this paper attempts to use the China5G case to analyze the factors contributing to Australia's negative foreign policy toward China. The paper argues that the definition of problems by the top governmental officials and the urgency of the problem mutually determine whether the final resolution is negative or positive toward a country; that the complexity of domestic political party structure and electoral politics imply the preference for national policy; and that the lead of public opinion, as well as the government's political intention to maintain the rule of legality, are the key factors affecting the policy orientation. This analysis aims to better understand the deep connotation of the relationship between China and Australia and provides a thinking path for improving relations between the two countries. It also refers to analyzing the attitudes towards China's rise from other countries in the Asia-Pacific region.

This article is concerned with the neural network (NN)-based event-triggered control problem for discrete-time networked Markov jump systems with hybrid cyberattacks and unmeasured states. The event-triggered mechanism (ETM) is used to reduce the communication load, and a Luenberger observer is introduced to estimate the unmeasured states. Two kinds of cyberattacks, denial-of-service (DoS) attacks and deception attacks, are investigated due to the vulnerability of cyberlayer. For the sake of mitigating the impact of these two types of cyberattacks on system performance, the ETM under DoS jamming attacks is discussed first, and a new estimation of such mechanism is given. Then, the NN technique is applied to approximate the injected false information. Some sufficient conditions are derived to guarantee the boundedness of the closed-loop system, and the observer and controller gains are presented by solving a set of matrix inequalities. The effectiveness of the presented control method is demonstrated by a numerical example.

This article investigates event-triggered and self-triggered control problems for the Markov jump stochastic nonlinear systems subject to denial-of-service (DoS) attacks. When attacks prevent system devices from obtaining valid information over networks, a new switched model with unstable subsystems is constructed to characterize the effect of DoS attacks. On the basis of the switched model, a multiple Lyapunov function method is utilized and a set of sufficient conditions incorporating the event-triggering scheme (ETS) and restriction of DoS attacks are provided to preserve performance. In particular, considering that ETS based on mathematical expectation is difficult to be implemented on a practical platform, a self-triggering scheme (STS) without mathematical expectation is presented. Meanwhile, to avoid the Zeno behavior resulted from general exogenous disturbance, a positive lower bound is fixed in STS in advance. In addition, the exponent parameters are designed in STS to reduce triggering frequency. Based on the STS, the mean-square asymptotical stability and almost sure exponential stability are both discussed when the system is in the absence of exogenous disturbance. Finally, two examples are given to substantiate the effectiveness of the proposed method.

In this article, the event-triggered resilient L∞ control problem is concerned for the Markov jump systems in the presence of denial-of-service (DoS) jamming attacks. First, a fixed lower bound-based event-triggering scheme (ETS) is presented in order to avoid the Zeno problem caused by exogenous disturbance. Second, when DoS jamming attacks are involved, the transmitted data are blocked and the old control input is kept by using the zero-order holder (ZOH). On the basis of this process, the effect of DoS attacks on ETS is further discussed. Next, by utilizing the state-feedback controller and multiple Lyapunov functions method, some criteria incorporating the restriction of DoS jamming attacks are proposed to guarantee the L∞ control performance of the event-triggered Markov closed-loop jump system. In particular, the bounded transition rates rather than the exact ones are taken into account. That is appropriate for the practical environment in which transition rates of the Markov process are difficult to measure accurately. Correspondingly, some criteria are proposed to obtain state-feedback gains and event-triggering parameters simultaneously. Finally, we provide two examples to show the effectiveness of the proposed method.

This article investigates stabilization problems of networked event-triggered switched systems under multiasynchronous switching. Different from the existing asynchronous literature, a novel problem is considered in this article, i.e., the event-triggering scheme and controller both have independent switching delays relative to the system, which is called multiasynchronous switching. An adaptive event-triggering scheme with switching structure is utilized to achieve better adjustment in triggering frequency. A systematic framework for analyzing multiasynchronous switching stability and solving controller gains is established. Different Lyapunov functionals are employed, and new tight bound conditions on average dwell time are constructed. Besides, an active packet loss approach for handling packets disorder issues caused by large transmission delays is presented. Since the activation instants of the system, triggering scheme, and controller are mutually staggered with the data updating instants of the actuator, a novel analytical method aiming at the coupling effect is proposed. Finally, the validity of the adopted method in this article is demonstrated.

This paper is concerned with H control problem for discrete-time Takagi-Sugeno (T-S) fuzzy Markov jump systems with event-triggering scheme (ETS) and denial-of-service (DoS) attacks. Aperiodic DoS characterized by duration and frequency is introduced. In the light of DoS attacks and event-triggered fuzzy controller, the switched fuzzy Markov jump closed-loop system is established. Particularly, in order to address the issue of mismatched behavior between membership functions of fuzzy system and fuzzy controller, a novel ETS consisting of membership functions is developed. Then with the help of multiple Lyapunov function method and iterative technique, some sufficient conditions are provided to ensure the H performance of the resulting closed-loop system. Subsequently, the explicit parameter design of controller and ETS are provided. Finally, an example is employed to verify the validity of the proposed theoretical method.

The problem of time-varying reliable H ∞ filtering for a class of discrete-time semi-Markov jump systems (S-MJSs) over a lossy network is considered in this paper. The communication channels between the system and the filter are supposed to be unreliable, which lead to the existences of randomly occurring sensor nonlinearities and imperfect transmission. Based on the semi-Markov kernel (SMK) method and stochastic analysis technique, some mode-dependent sufficient conditions are derived and time-varying reliable filters are designed, which guarantee that the filtering error system is σ -error mean square stable with an H ∞ performance index. Two numerical examples are given to show the usefulness of proposed filter design method.

This paper investigates the event-triggered H ∞ control problem for network-based Markov jump systems subject to denial-of-service (DoS) attacks. In order to reduce the amount of signal transmission, the event-triggering scheme (ETS) is adopted between sensor and controller. Due to DoS attacks invalidating data over networks, a new switched time-delay Markov jump model with unstable subsystems is developed based on state feedback controller. Then with the help of piecewise Lyapunov-Krasovskii functional method, a set of sufficient conditions incorporating constraints of DoS attacks are provided, which guarantees that the resulting switched time-delay Markov jump system is stochastically stable with a certain H ∞ performance. Subsequently, we present criterions to obtain the parameters of state feedback gain and ETS. Finally, an example is provided to show the effectiveness of the proposed method.

This paper studies the problem of event-triggered and self-triggered $\boldsymbol {H}_{\boldsymbol {\infty }}$ controls for uncertain switched linear systems with exogenous disturbances whose magnitude is bounded by the system state’s norm. With the proposed schemes, the control task is carried out only when the triggering condition is met. That leads to changing and adaptive interexecution intervals and can further reduce the system resource costs to a certain extent. Moreover, to ensure the $\boldsymbol {H}_{\boldsymbol {\infty }}$ control performance of the event-triggered switched system, a proof which makes certain that the occurrence of Zeno problem can be prevented is first provided. Then, by adopting the average dwell time method, a set of sufficient conditions for $\boldsymbol {H}_{\boldsymbol {\infty }}$ performance analysis is developed. Subsequently, the codesign of controller gains and event-triggering schemes is provided. On the basis of the event-triggered control, a solution to the self-triggered control problem is then presented. It can only utilize the current sampled data to predict the next triggered instant. Finally, in order to test the effectiveness of the proposed methods, numerical simulations are performed.

In this article, the event-triggered resilient L

In the construction of smart city, this paper proposes a new waterlogging measurement mode: multiple small sensors are used as waterlogging information collection terminals, LoRa technology forms a wide area information network, STM32 series microcontroller and LoRa technology feed back the waterlogging terminal information to the information processing terminals. Digital mapping technology to get an intuitive map of waterlogging conditions, Through digital map technology, intuitive waterlogging map can be obtained, and the water level of each point can be networked to serve waterlogging prevention and control in smart cities in a more specific and accurate way.

In this paper, the sampled-data resilient H ∞ control problem is concerned for networked stochastic systems with multiple attacks. Multiple attacks consisting of denial-of-service (DoS) attacks and random deception attacks are first described. Then on the basis of these attacks, a new switched stochastic time-delay closed-loop system is proposed under sampled-data and full state feedback controller. By utilizing piecewise Lyapunov-Krasovskii functional analysis theory, some new criterions are derived to guarantee the mean-square asymptotical stability with an H ∞ performance of the resulting closed-loop system. The explicit expression of controller gain is subsequently presented. Finally, two examples are given to show the feasibility of the developed control approach.

In this paper, an event-triggering scheme is implemented in uncertain switched linear systems with time-varying delays and exogenous disturbance. Instead of standard periodically time-triggered, sampled-data control systems, the event-triggered control systems sample data only when an event, typically defined as some performance error exceeding a tolerant bound, occurs. Specifically, considering the disturbance existing in the system, the event-triggered robust H∞ control problem is studied. In order to guarantee the robust H∞ performance, the event-triggered full state feedback control, multiple Lyapunov functions method and state-dependent switching law are utilised to construct sufficient conditions in terms of linear matrix inequalities. In particular, since the event-triggered signals and switching signals may interlace with each other, the influence from them on the analysis of robust H∞ performance is clarified. Subsequently, sufficient design conditions of the sub-controllers’ gains are fu...

This paper investigates the event-triggered L ∞ control for network-based switched linear systems with transmission delay. Necessary samplings of the feedback signal are determined by the improved periodic sampling based event-triggering schemes with extra design parameters, which can further reduce redundant signal transmissions and updates. Moreover, under the state feedback control, a time-delay closed-loop switched system is developed. Particularly, in the developing process an active packet loss technique is given to fully deal with the relationship between the network transmission delay and sampling period. Then by utilizing the piecewise Lyapunov functional method and average dwell time technique, sufficient conditions in terms of linear matrix inequalities (LMIs) are constructed to render the time-delay closed-loop switched system globally uniformly ultimately bounded (GUUB) and having an L ∞ performance. In addition, since the event-triggered instants and switching instants both exist in the system and may stagger with each other, their coupling effect on the stability analysis is clarified. Subsequently, the conditions for finding the parameters of state feedback gains and improved event-triggering schemes are presented. An example is provided to show the effectiveness of the proposed method.

This paper studies the guaranteed cost state-feedback control for uncertain switched linear systems with an event-triggering strategy. With the proposed event-triggering strategy, the system state can be sampled and updated only when a defined error exceeds a given threshold, which is very different from the traditional periodic sampling. More specifically, first, sufficient conditions for the stability and guaranteed cost performance of the resulting event-triggered switched closed-loop system are derived by utilizing the average dwell time method and linear matrix inequalities (LMIs) technique. A certain upper bound of the guaranteed cost against the system uncertainties is obtained. Subsequently, another set of sufficient conditions are presented for solving the event-triggered guaranteed cost state-feedback controllers. Furthermore, the Zeno behavior is discussed by presenting a positive lower bound estimation on the inter-execution intervals. Finally, numerical simulations are provided to demonstrate the effectiveness of the proposed approach.

This paper studies the event-triggered H ∞ control of switched linear systems with time delay. In the framework of state feedback control, an event-triggering strategy is adopted to replace the traditional periodic sampling strategy. By utilizing such strategy, the state is sampled and transmitted if and only if the defined event-triggering condition is satisfied. Specifically, first, sufficient analysis conditions for the stabilization of switched closed-loop system with time delay are developed by using multiple Lyapunov functions approach and linear matrix inequalities (LMIs) technique. Consequently, sufficient design conditions for solving the event-triggered controllers' parameters are presented. Then, to avoid continuously sampling/triggering, Zeno behavior is discussed. Finally, numerical simulations verify the effectiveness of the proposed method.

This paper concerns the stabilization of switched linear systems with an event-triggered control strategy. Different from the traditional sampled-data control systems whose controller updates signals periodically, the presented event-triggering scheme samples signals according to the current system performance, and its event-triggered condition depends on the error between the present state and the latest sampled and transmitted state. With the proposed event-triggering scheme, multiple Lyapunov functions method and linear matrix inequality (LMI) technique are adopted to design the stabilizing controllers, and the corresponding sufficient conditions are obtained to guarantee the asymptotic stability of the resulted event-triggered, switched closed-loop system. Moreover, a lower bound estimation on the inter-execution intervals is given to avoid Zeno behavior. Numerical simulations are provided to show the effectiveness of the approach.

Undoubtedly, Peer-to-Peer (P2P) technology is an effectively method for delivering streaming media content over the Internet. However, current P2P stream systems also suffer many problems, such as huge bandwidth consumption, less effective in heterogeneous environment, etc. Scalable video coding (SVC), as an extension of H.264/AVC standard, has attracted many researchers for its flexible scalability and adaptability to the heterogeneous network. Network coding, an innovation of the field of information theory, is proved to be valuable in P2P application. In this paper, we propose two different network coding schemes (multi-layer network coding and infra-layer network coding), combining with SVC technology to solve the above problems. Simulation result shows system gain significant improvement by employing network coding, especially by infra-layer network coding.

Lead sulfide quantum dots (QDs) were prepared by liquid phase method. The particle size can be controlled by changing the concentration of reactants and surfactant and the size of the QDs varies from 7[Formula: see text]nm to 20[Formula: see text]nm, which results in the change of the optical properties and the band gap of the particles. The optical band gap of lead sulfide QDs increased drastically with the decrease of the diameter of the sample QDs.

Undoubtedly, peer-to-Peer (P2P) technology is an effectively method for delivering streaming media content over the internet. However, current P2P stream systems also suffer many problems, such as huge bandwidth consumption, less effective in heterogeneous environment, protection of important data, etc. Scalable video coding (SVC), as an extension of H.264/AVC standard, has attracted many researchers for its flexible scalability and adaptability to the heterogeneous network. Network coding, an innovation of the field of information theory, is proved to be valuable in P2P application. In this paper, we propose two different network coding schemes (multi-layer network coding and intra-layer network coding), combining with scalable video coding technology to solve the above problems. Simulation result shows system gains a significant improvement by employing network coding, especially by intra-layer network coding.