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This article addresses the hybrid H ∞ filtering problem for continuous-time uncertain linear impulsive switched systems with the asynchronous switching. Unlike most work about filtering problems, this article ponders multiple state impulsive jumps in the whole switched systems. In other words, the state impulsive jumps take place in subsystem switching instants as well as in filter switching instants, which add challenges to the H ∞ filtering problem considered in this article. In the filter design, one has to take account of the asynchronous switching, which hints that the switching of the subsystem and its corresponding filter does not occur concurrently. The average dwell time approach is applied to design the switching rule. This article focuses on the design of the hybrid H ∞ filter that can keep the filtering error systems globally uniformly asymptotically stable with H ∞ performance index. By constructing Lyapunov-like functions that allow the increment during the asynchronous period and in the state jump instants, sufficient conditions for the expected hybrid H ∞ filter are obtained in the form of linear matrix inequalities. At last, an example is offered to demonstrate the applications of the acquired theorems. [ABSTRACT FROM AUTHOR]

Hydrogen production through seawater electrolysis faces several challenges, one of which involves the development of electrocatalysts with high catalytic performance. Here, surface amorphization and morphology engineering are combined to design a novel electrocatalyst for highly‐efficient hydrogen evolution reaction (HER). The surface‐amorphized MoO2/Ni3(PO4)2 microcolumns supported on nickel foam (SA‐MoO2/Ni3(PO4)2/NF) display remarkable performance with low overpotentials of 34 and 46 mV at a current density of 10 mA cm−2 in 1 m KOH and alkaline seawater, respectively. In addition, the alkaline electrolysis cell (AEC) integrated with SA‐MoO2/Ni3(PO4)2/NF as the cathode and Ni foam as the anode achieves a current density of 100 mA cm−2 at 1.87 V in 6 m KOH seawater at 60 °C, superior to that of industrial NiMo electrode as cathode (2.05 V). DFT calculations demonstrate that the surface amorphous layer (MoOx) improves the hydrogen adsorption energy of sample and reduces the energy barrier of water dissociation. It is found that substantial improvement in catalytic performance stems from the synergistic effect between surface amorphization and unique microcolumn morphology. These findings may provide insights into combining surface amorphization and morphology engineering strategies to enhance catalytic performance and pave the way for the development of highly efficient seawater HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Summary: This article investigates the quantized H∞$$ {H}_{\infty } $$ dynamical output feedback (DOF) control problem for uncertain impulsive switched systems (ISSs) with multiple state impulsive jumps, where the static quantization strategy is applied to quantize the control input to improve the signal transmission capacity of ISSs. First, to correspond the abrupt changes for states of ISSs at switching moments, the controller states are also allowed to jump besides the system state jumps of ISSs, which increases the universality of the impulsive behavior in ISSs. Second, the multiple Lyapunov functions approach and the average dwell time switching strategy are applied to derive the sufficient conditions that guarantee the stability and weighted H∞$$ {H}_{\infty } $$ performance of the closed‐loop uncertain ISSs. The desired hybrid controllers comprising of DOF controllers for every subsystem and controller state update rules at switching instants can be constructed by solving a set of linear matrix inequalities. Finally, a numerical example is provided to verify the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]

The article discusses the signs and patterns on China's efforts to open up its economy to the world, particularly the implementation of its Belt and Road Initiative (BRI). Also cited are the changing objective of China for its BRI, the alleged efforts by the U.S. to contain China's development and their impacts on China's national security, and BRI's alleged goal to promote peace, development, and win-win global cooperation.