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This study is concerned with the stabilization analysis and controller design for networked systems with stochastic sampling and two‐channel deception attacks. First, we give a general matrix decomposition approach which is applicable to scenarios where the system matrix A$A$ contains complex‐value eigenvalues. Then, a discrete stochastic framework is established for a class of networked systems which considers the joint effects of sampling errors and two‐channel deception attacks. Utilizing the matrix decomposition approach introduced in this study, it becomes feasible to decouple the expectation operations for specific coupling matrices characterized by substantial nonlinearity and randomness. Based on this, a stabilization controller is constructed that ensures the exponential mean‐square stability of the resulting discrete stochastic system. Finally, three simulation examples are provided to validate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Event-triggered schemes are characterized in less communication traffic while maintaining the resulting controlled plant’s desired stability and performance criteria. In the presence of packet dropouts, this paper is concerned with the modeling and control problems for a class of discrete-time stochastic systems with event-triggered schemes. Two different mathematical analysis methods are proposed to model the packet loss when an event-triggered scheme is subject to packet loss. First, a stochastic distributed sequence satisfying the Bernoulli process is utilized to model the triggered packets transmitted in the communication networks. Considering the difference between time-triggered and event-triggered schemes, an equivalent model with a random sequence not satisfying a Bernoulli distribution process is also analyzed, which is not the same as some existing results in the literature. Then, the mean-square exponential stability of resulting augmented system is guaranteed and the prescribed ${H}_{\infty }$ performance level is achieved by solving resulting discrete ${P}$ -problem. Two examples with simulations are provided to validate the analytical results and demonstrate the effectiveness of the proposed co-design techniques. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the modeling and stabilization problems for a class of discrete-time stochastic networked systems (DSNSs) subject to successive packet losses. The system under consideration is transformed into a stochastic one with bounded stochastic delay. Considering that the stochastic delay is characterized by nonuniform distribution, a new equivalent model is then constructed that enables the DSNS’s controller design to benefit from knowing the probability characteristic of packet losses. Specially, to verify this feature, the probabilities of the delay can be explicitly obtained by utilizing the formula of total probability, which is critical to model transformation and analyze practical problems that exist in DSNSs. Based on the proposed model, sufficient conditions are established under which the globally mean-square asymptotic stability of resulting stochastic delay closed-loop system is guaranteed, and a delay-distribution-dependent design procedure is then proposed. A numerical example with simulation is provided to validate the analytical results and demonstrate the effectiveness of the design procedure. [ABSTRACT FROM AUTHOR]

This paper considers the sample-data-based consensus problem of multiagent systems with time-varying delay and packet losses. To distinguish the time delays caused by network-induced time-delay and packet losses, the switched system is utilized. A lower gain controller is designed based on the solution of a parametric algebraic Riccati equation. The Lyapunov stability theory is utilized to obtain the limitations on the frequency and the duration of packet losses which guarantees the consensus of multiagent systems. On the other hand, we theoretically prove that refined time-delay function can reduce the conservatism. A simulation example is given to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Doping with nitrogen atoms can improve the catalytic activity of activated carbon cathodes in electro-Fenton systems, but currently there is a lack of understanding of the catalytic mechanism, which limits the further development of high-performance activated carbon cathodes. Here, a multi-scale exploration was conducted using density functional theory and experimental methods to investigate the mechanism of different nitrogen doping types promoting the redox performance of activated carbon cathodes and the degradation of phenol. The density functional theory results indicate that the introduction of nitrogen atoms enhances the binding ability between carbon substrates and oxygen-containing substances, promotes the localization of surrounding electrons, and makes it easier for O 2 to bind with protons and catalyze the hydrogenation reaction of *OOH. Due to its weak binding ability with oxygen-containing substances, AC is difficult to form H 2 O 2 , resulting in a tendency towards the 4e−ORR pathway. The binding energy between graphite-N carbon substrate and pyridine-N carbon substrate with *OOH is closer to the volcano top, so graphite n and pyridine n can better promote the selectivity of activated carbon for 2e-ORR. In addition, the calculation results also indicate that pyrrole-N and graphite-N are more capable of catalyzing the reaction energy barrier between ·OH and phenol. Finally, the simulation results were used to guide the modification of nitrogen doped activated carbon and experimental verification was carried out. The degradation results of phenol confirmed the efficient synergistic effect between different types of nitrogen doping, and the NAC-800 electrode exhibited efficient and stable characteristics. This work provides a guiding strategy for further developing stable and highly selective activated carbon cathode materials. • Nitrogen doping improves the bonding ability between AC cathode and *OOH. • Graphene-N and pyridine-N increased the 2e-ORR selectivity of activated carbon. • Pyrrorole-N and graphite-N have catalytic effects on the degradation of phenol. • There are effective synergies between different types of nitrogen doping. • Nitrogen doping can promote the formation of H 2 O 2 and the degradation of phenol. [ABSTRACT FROM AUTHOR]

Phase change material (PCM) can effectively reduce temperature fluctuations in greenhouses and increase crop yields. Plastic greenhouses are a major form of facility agriculture in southern China, and there are no walls in it. Therefore, how to combine plastic greenhouses with PCM has become research hotspot. A new type of high absorption latent heat storage plate (LHSP) was proposed. That is to lay PCM plates on the north side of the plastic greenhouse vertically. To enhance solar energy utilization and reduce heat loss, solar high absorption and thermal insulation layer were respectively placed on the sunny side and shady side. Two greenhouses were constructed and LHSP was placed in one greenhouse as Case 1. After that, a solar high absorption film and thermal insulation layer were attached to the sunny side and the shady side as Case 2 and Case 3. The average air temperature of two greenhouses and the thermal performance of LHSP were compared under three cases. Results showed that, in Case 1, the LHSP can raise the average air temperature inside the greenhouse by 1.8–2.9 °C during the night. in Case 2 and 3, the average air temperature had a stable improvement of 1.6–2.2 °C and 1.8–2.1 °C respectively at night. Besides, in Case 2, the heat storage of LHSP on sunny side had increased by 26.2%. In Case 3, the total average heat loss of LHSP was reduced by 21.5% and the average heat release from sunny side had risen by up to 39.7%. The high absorption latent heat storage plate showed excellent thermal performance. [ABSTRACT FROM AUTHOR]

The use of the electro-Fenton process to continuously generate H 2 O 2 and efficiently degrade organic pollutants is considered a promising technology. The ratio of generation of H 2 O 2 is usually regarded as the critical step; however, how the H 2 O 2 is utilized is also of particular importance. Herein, activated carbon was activated at different temperatures and used to explore the effect of nitrogen doping on the production and utilization of H 2 O 2 in the electro-Fenton-based degradation of organic pollutants. The experimental results indicate that nitrogen-doped activated carbon simultaneously promotes the generation and utilization of H 2 O 2 , which is attributed to the regulation of the competition between phenol and O 2 adsorption by the doped nitrogen. Nitrogen doping not only improves 2e−ORR selectivity but also aggregates phenol near the cathode to balance the concentrations of phenol and ·OH. Density functional theory (DFT) calculations further confirmed that pyrrole-N as a dopant promoted the adsorption of phenol, while pyridine-N was more favorable for O 2 adsorption. The unique balance of nitrogen types possessed by modified activated carbon NAC-750 permits the efficient synergistic generation and utilization of H 2 O 2 in a balanced manner during the degradation of phenol. This work provides a new direction for the rational nitrogen-doping modification of activated carbon for the electro-Fenton-based degradation of organic pollutants. [Display omitted] • The adsorption of phenol affects the adsorption of O 2 and the generation of H 2 O 2. • Graphite-N is the main site for the competitive adsorption of phenol and O 2. • Competition can be effectively regulated by regulating nitrogen doping types. • Reasonable nitrogen doping can promote the generation and utilization of H 2 O 2. [ABSTRACT FROM AUTHOR]