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This paper focuses on the leader-following consensus control problem of stochastic multi-agent systems with hysteresis inputs and nonlinear dynamics. A leader-following consensus scheme is presented for stochastic multi-agent systems directions under directed graphs, which can achieve predefined synchronisation error bounds. By mainly activating an auxiliary robust control component for pulling back the transient escaped from the neural active region, a multi-switching robust neuro adaptive controller in the neural approximation domain, which can achieve globally uniformly ultimately bounded tracking stability of multi-agent systems recently. A specific Nussbaum-type function is introduced to solve the problem of unknown control directions. Using a dynamic surface control technique, distributed consensus controllers are developed to guarantee that the outputs of all followers synchronise with that of the leader with prescribed performance. Based on Lyapunov stability theory, it is proved that all signals in closed-loop systems are uniformly ultimately bounded and all the follower agents can keep consensus with the leader. Two simulation examples are provided to illustrate the effectiveness and advantage of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) images are inevitably contaminated by speckle noise due to its coherent imaging mechanism. Speckle noise obscures the intrinsic radar cross section (RCS) information in SAR images. This article proposes a novel deep neural network architecture specifically designed for despeckling purpose. It uses a convolutional neural network to extract image features and reconstruct a discrete RCS probability density function (PDF). It is trained by a hybrid loss function which measures the distance between the actual SAR image intensity PDF and the estimated one which is derived from convolution between the reconstructed RCS PDF and prior speckle PDF. The network can be trained by either purely simulated image patches or real SAR images. Experiment results on both simulated SAR images and real NASA/JPL AIRSAR images are used to test the performance, and the results show the efficacy of the proposed despeckling neural network compared with three state-of-the-art filters. [ABSTRACT FROM AUTHOR]

This paper addresses an observer-based consensus problem for leader-following control of a class of linear multi-agent systems (MASs) under a directed communication topology via event-triggered approaches. State observers are employed to tackle the scenario wherein inner information of the follower agents are not available for measurement. And then, an observer-based distributed leader-following control scheme is developed on the basis of event-triggered mechanisms. Further, to avoid continuous measurement information monitor, we present a technical approach for generation of the combinational information from their own neighbouring agents only at triggered instants. In theory, the stability of the resulting closed-loop system is rigorously investigated, and it is proven that all signals in the closed-loop system are bounded and Zeno behaviour is also excluded. Finally, simulation examples are presented for illustration of the theoretical claims. [ABSTRACT FROM AUTHOR]

Considering interconnections among subsystems, we propose an adaptive neural tracking control scheme for a class of multiple-input-multiple-output (MIMO) non-affine pure-feedback time-delay nonlinear systems with input saturation. Neural networks (NNs) are employed to approximate unknown functions in the design procedure, and the separation technology is introduced here to tackle the problem induced from unknown time-delay items. The adaptive neural tracking control scheme is constructed by combining Lyapunov–Krasovskii functionals, NNs, the auxiliary system, the implicit function theory and the mean value theorem along with the dynamic surface control technique. Also, it is proven that the strategy guarantees tracking errors converge to a small neighbourhood around the origin by appropriate choice of design parameters and all signals in the closed-loop system uniformly ultimately bounded. Numerical simulation results are presented to demonstrate the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

This paper investigates the distributed adaptive event-triggered consensus control for a class of nonlinear agents. Each agent is subject to input saturation. Two kinds of distributed event-triggered control scheme are introduced, one is continuous-time-based event-triggered scheme and the other is sampled-data-based event-triggered scheme. Compared with the traditional event-triggered schemes in the existing literatures, the parameters of the event-triggered schemes in this paper are adaptively adjusted by using some event-error-dependent adaptive laws. The problem of simultaneously deriving the controller gain matrix and the event-triggering parameter matrix, and tackling the saturation nonlinearity is cast into standard linear matrix inequalities problem. A convincing simulation example is given to demonstrate the theoretical results. [ABSTRACT FROM AUTHOR]

In this note, the distributed event-triggered cooperative attitude control of multiple rigid bodies with leader–follower architecture is investigated, where both the cases of static and dynamic leaders are all considered. Two distributed triggering procedures are first introduced for the followers and leaders, and then the distributed cooperative controllers are designed under the proposed triggering schemes. Under the designed controllers with the event-triggered strategies, it is shown that the orientations of followers converge to the convex hull formed by the desired leaders’ orientations with zero angular velocities. Moreover, the communication pressure in network is reduced and the energy of each agent is saved. Simulation results show the effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]

The article investigates theH∞filtering problem for a class of discrete-time networked systems with random measurement losses and delays. Markov chain is used here to model measurement losses and delays in a unified framework. Based on the mode-dependent Lyapunov function approach, the necessary and sufficient conditions are derived to guarantee the exponential stability with a prescribedH∞disturbance attenuation performance for the filtering error system. By using a novel design scheme, the explicit expressions of mode dependent filter parameters are given in the form of linear matrix inequalities (LMIs) which can be readily solved by using the LMI TOOLBOX in MATLAB. At last, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]

A new delay fraction technique is proposed to investigate the H ∞ control of uncertain systems with time delay in state or input. First, the variation interval of the time-varying delay is divided into several subintervals with equal length. By checking the variation of derivative of the Lyapunov functional in every subinterval, some new criteria on H ∞ performance analysis of the systems are derived in terms of the convexity properties of a matrix inequality and some other new analysis techniques. Then, criteria for the H ∞ control design are presented, which are concluded from the H ∞ performance analysis results. As applications of the derived results, H ∞ performance analysis and H ∞ control design are carried out for some systems, including two numerical systems, linearised truck trailer system and traffic network system. Discussions show that, the proposed method is effective for these systems and much less conservativeness appears than those given in the existing references. [ABSTRACT FROM PUBLISHER]

The article discusses various papers presented within the issue, including "Dynamics of gossip-like information dissemination in complex computer networks," by Nekovee and Moreno and "Dealing with network complexity in real-time networked control," by Tian and Levy.

This paper is concerned with the global robust asymptotical stability for a class of cellular neural networks with time-varying delays and parameter uncertainties. By using the Lyapunov-Krasovskii functional method and employing the convexity of the matrix equation, some new stability criteria are derived, which are expressed by a set of linear matrix inequalities. To show the effectiveness and less conservatism of our method, two numerical examples are presented finally. [ABSTRACT FROM AUTHOR]

A variety of fluorinated compounds of β-amino ketones could be obtained in good to excellent yields at room temperature through a three-component Mannich reaction of aldehydes, anilines, and acetones catalyzed by iodine. [ABSTRACT FROM AUTHOR]

2‐Acylimino‐3‐aryl‐3 H ‐thiazoline derivatives could be generated in excellent yields through three‐component condensations of aroylisothiocyanates, primary amines, and ω‐haloacetophenone under solvent‐free microwave irradiation. [ABSTRACT FROM AUTHOR]

Cholesterol crystals participate in cholesterol nucleation; however, the role of cholesterol crystals in gallstone development is unknown. Mucin secretion contributes to increased size of gallstones. Cholesterol crystals activate inflammasomes and participate in many sterile inflammation related human diseases. We investigated the role of cholesterol crystals and mucins in sterile inflammation and gallstone enlargement. We found that expression of mucin 5AC (MUC5AC), NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) and interleukin-1b (IL-1b) was increased significantly in tissues adjacent to gallstones. Experiments in vitro showed that cholesterol crystals promote MUC5AC secretion; they also increase expression of NLRP3, NLR family CARD domain-containing 4 (NLRC4), apoptosis-associated speck-like protein containing caspase recruitment domain (ASC), and cleaved caspase-1 in biliary epithelial cells. Inhibition of Inflammasomes by NLRP3, ASC or caspase-1 small interfering RNAs reduced MUC5AC secretion. Also, the IL-1 receptor antagonist, IL1RA, and caspase-1 inhibitor, Ac-YVAD, both inhibited MUC5AC secretion induced by cholesterol crystals. We found that inflammasome activation participates in cholesterol crystal induced mucin secretion and gallstone development. [ABSTRACT FROM AUTHOR]

For distributed energy resources (DERs) in islanded microgrid (MG), to improve the control effect on the output voltages and frequency from droop control, a novel distributed control strategy is proposed in this article based on the concept of cyber physical system (CPS). The novel control structure is consisted by the cyber and the physical layers. In the cyber layer: firstly, the communication structures of overall microgrid and single DER are constructed; then, based on the communication structures, the influence of time-delay (delay) and packet loss (loss) on consensus control is analyzed in this article; And then, an event-triggered mechanism combined with adapt virtual leader-following consensus control (AVLFCC) and predictive compensation is proposed in this layer. It is used to solve the problem of time-varying delay and loss rate in the process of consensus control. In the physical layer: firstly, the droop control is used as the primary control on the output voltages and frequency of DERs; then, a novel secondary control method is proposed by using the event-triggered mechanism. And finally, the simulation results confirm the effectiveness of the novel distributed control strategy under communication problems (delay and loss) and during plug-and-play operation. [ABSTRACT FROM AUTHOR]

Rendezvous problem of nonholonomic unicycles has been considered in this paper and nonlinear distributed controllers based on backstepping are constructed to guarantee the consensus of both position and direction simultaneously. Cascaded theory of nonlinear system is utilised to reduce the rendezvous problem of nonholonomic unicycles to consensus problem of moving direction and consensus problem of position, respectively. The uncontrollable challenge of position system after consensus of moving direction has been successfully removed through dilated coordinate transformation. Then, a modified backstepping methodology based on the coupling structure of position system is derived to guarantee the consensus of each unicycle's position. In the end, not only consensus of position but also consensus of direction has been realised for multiple nonholonomic unicycles using the controllers proposed in this paper. Simulation results using Matlab illustrate the effectiveness of the results of this paper. [ABSTRACT FROM AUTHOR]

Context: Non-alcoholic fatty liver disease (NAFLD), the most common chronic liver disease, can develop into metabolic associated fatty liver disease (MAFLD). Gypenosides (GP), the main phytochemical component of Gynostemma pentaphylla (Thunb.) Makino (Cucurbitaceae), have been applied for treatment of metabolic diseases. Objective: We investigate how GP modulate MAFLD-related hepatic steatosis and intestinal barrier injury. Materials and methods: In cell experiments, Caco-2 cells were treated with GP (150 or 200 lmol/L, 24 h), following lipopolysaccharide (LPS) exposure (10 lg/mL, 24 h) to mimic MAFLD in vitro. In in vivo experiments, control, model and modelþGP groups were set. High fructose diet/high fat (HFD/HF)-fed (12 weeks) MAFLD rats received GP treatment (300mg/kg, 6 weeks), followed by intra-peritoneal glucose tolerance test and histopathological examination of rat liver and intestinal mucosa using haematoxylin-eosin staining. Results: GP at 200 lM significantly reversed LPS-induced decreases in transepithelial electrical resistance (TER) value (25%), protein expression of occludin (two fold) and ZO-1 (four fold), and the ratio of p-AMPK to AMPK (five fold), while partially repressing LPS-induced leakage of FD4 (50%) and LPS-induced increases in the Toll-like receptor 4 (TLR4) level (50%) and the ratio of p-p65 to p65 (55%). Compared with the model rats, rats with GP treatment presented a reduction in gain of weight and glucose tolerance. In addition, GP alleviated HFD/HF-induced histopathological abnormalities in rat liver and intestinal mucosa. Conclusions: GP attenuates hepatic steatosis and intestinal barrier injury in MAFLD rats via the AMPK and TLR4/nuclear factor kappa B (NF-jB) pathways, providing a potential treatment for MAFLD patients. [ABSTRACT FROM AUTHOR]

This article focuses on multi-agent system based hierarchical energy management strategies for maximum economic and environmental benefits for microgrids. First, a two-level multi-agent based energy management system is constructed, which consists of an upper-level EMA in the view of whole system, multiple lower-level unit agents in a distributed manner, and their interactions based on communication. Second, in the upper-level agent, the energy management strategies are mainly designed by constructing multi-objective functions and by using a particle swarm optimization method based on hybrid probabilistic forecasting of renewable energy sources and loads. Third, in lower-level renewable energy source and load agents, the forecasting approach regarding renewable energy sources and loasd is mainly researched by means of the ensemble empirical mode decomposition combined with sparse Bayesian learning, called the hybrid probabilistic forecast approach. Moreover, in lower-level schedulable generation unit agents, local control strategies are also presented to regulate the output power to satisfy the reference power that is set by the upper-level agent. Finally, the validity of the proposed multi-agent based energy management strategies is demonstrated by means of simulation results. [ABSTRACT FROM AUTHOR]

This paper deals with the problem ofH∞filtering for discrete-time systems with stochastic missing measurements. A new missing measurement model is developed by decomposing the interval of the missing rate into several segments. The probability of the missing rate in each subsegment is governed by its corresponding random variables. We aim to design a linear full-order filter such that the estimation error converges to zero exponentially in the mean square with a less conservatism while the disturbance rejection attenuation is constrained to a given level by means of anH∞performance index. Based on Lyapunov theory, the reliable filter parameters are characterised in terms of the feasibility of a set of linear matrix inequalities. Finally, a numerical example is provided to demonstrate the effectiveness and applicability of the proposed design approach. [ABSTRACT FROM AUTHOR]

In this paper, an event-triggered adaptive approximately optimal tracking control approach is proposed for a class of non-affine nonlinear single-input single-output (SISO) systems via output feedback. With the help of fuzzy logic systems (FLSs), a fuzzy state observer is designed for the estimation of internal states by approximating unknown nonlinear functions, where a low-pass filter (LPF) is added for the algebraic loop problem. Then, the output feedback control approach, in the backstepping framework and the event-triggered mechanism, is presented. It contains the adaptive backstepping control and the approximately optimal control via adaptive dynamic programming (ADP) technology, and the computation cost and transmission load are reduced while guaranteeing that the performance index of the system is approximately minimised. Finally, two simulation examples are provided to verify the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

2-Amino-4-aryl-4 H -pyran derivatives could be prepared rapidly and smoothly in good to excellent yields by the microwave-assisted liquid-phase strategy of multicomponent synthesis on polyethylene glycol. [ABSTRACT FROM AUTHOR]

This paper focuses on multi-agent-system-based bi-level bidding strategy of microgrid to make all power producers participate in electricity allocation as rational agents under electricity market transaction. Firstly, the multi-agent-system-based bidding system is constructed as bi-level MAS. Then, the bidding model is formulated as a bi-level optimization problem, which makes the best of renewable energy source, and subjects it to the object of obtaining maximum profits for all power producers. According to this model, electricity market is divided into two subsidiary markets, which involve the upper and the lower electricity market. The lower electricity market is composed of microgrids, which ally together in the upper electricity market to offset their shortages compared to traditional power producers, such as efficient market influence, the reliability of the energy supplying. Additionally, game theory is introduced for modeling and Nash equilibrium as the solution of bidding optimization problem is found through a series of iterative process based on the bi-level MAS. Finally, both the upper market and the lower market are illustrated in the case studies and corresponding proper conclusions are received. [ABSTRACT FROM AUTHOR]

Triodontophorusspp. parasitizes the large intestine of equine, causing strongylid diseases. The present study assessed genetic variation in five gene regions within and betweenTriodontophorus brevicaudaandTriodontophorus nipponicusfrom Heilongjiang Province and the Inner Mongolia Autonomous region. The five gene markers were three mitochondrial (mt) genes, cytochromecoxidase subunit I (cox1), NADH dehydrogenase subunit 5 (nad5), cytochromeb(cytb); and two ribosomal RNA genes, the internal transcribed spacer 1 (ITS1) and the internal transcribed spacer 2 (ITS2). Partial (p) sequences ofcox1,nad5,cytb and the complete ITS rDNA region were PCR amplified from individual nematodes, and the amplicons were subjected to sequencing in both directions. The size of the three mt genes is identical in both species: 761 bp (pcox1), 505 bp (pnad5) and 562 bp (pcytb); the length of the two ribosomal genes is different: 376 bp and 370 bp (ITS1), and 333 bp and 322 bp (ITS2), respectively. Intraspecific variation betweenT. brevicaudaandT. nipponicuswas 0–1.5% and 0–1.1% for pcox1, 0–2.0% and 0–2.0% for pnad5, 0–1.4% and 0–2.2% for pcytb, 0–0.8% and 0–1.1% for ITS1 and 0–0.9% and 0–2.2% for ITS2. Interspecific variation within the nematodes was 13.5–14.3% for pcox1, 15.5–18.7% for pnad5, 16.7–18.6% for pcytb, 11.5–13.1% for ITS1 and 16.0–18.4% for ITS2. Phylogenetic analyses based on the combined mt gene sequences, as well as with the ITS sequences, show each species forming a monophyletic group of individuals. However, samples of different species from the same geographical origin did not always cluster together. These results provide valuable information for further studies of systematics and population genetics of the genusTriodontophorus. [ABSTRACT FROM PUBLISHER]

For the load frequency control (LFC) of the interconnected power system, a two-level coordinated control frame based on multi-agent system is proposed to improve the frequency control performance of the power system. In the control frame, the upper-level agent, in a centralized manner, coordinates the lower-level LFC agents to deal with the conflict between narrowing the area control error and stabilizing the system frequency. The lower-level LFC agents, in the distributed cooperative manner, realize the mutual power support among the neighboring areas to guarantee the frequency stability in an emergency. To verify the validity of the proposed method, the numerical simulations are performed on the three-area interconnected power systems. [ABSTRACT FROM AUTHOR]