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The problem of robust finite-horizon l2-l∞ filtering is investigated for a class of discrete-time Markovian jump systems under denial-of-service attacks. The considered dynamic model is more appropriate, on account of polyhedral feature of time-varying transition probabilities. Denial-of-service attack that may jam or compromise the measurement packets on communication channels is assumed as a Bernoulli distributed sequence. Based on stochastic Lyapunov function approach, sufficient criteria corresponding to the error system are established for designing a finite-horizon l2-l∞ filter in the light of linear matrix inequalities. In the end, three illustrative examples are worked out to substantiate the theoretical results. [ABSTRACT FROM AUTHOR]

Summary: In this article, the problem of robust finite‐time H∞ synchronization control is investigated for a class of uncertain discrete‐time master‐slave systems with Markovian switching parameters in the observer‐based case. Parameter uncertainties are assumed to be norm‐bounded, and the polyhedral character is utilized to describe the transition probabilities of nonhomogeneous Markov chain. By using stochastic Lyapunov function method and finite‐time analysis techniques, novel sufficient conditions that include the master‐slave parameters are obtained for designing an observer‐based finite‐time H∞ synchronization control law in terms of linear matrix inequalities. The effectiveness of the proposed theoretical scheme is finally demonstrated by some simulations. [ABSTRACT FROM AUTHOR]

An anatase TiO2 photoanode with a novel three-dimensional nest-like structure was prepared directly on a transparent conductive glass substrate through hydrothermal cycles by three times. First, an unidirectional banded structure film was prepared by a facile hydrothermal method. And then, with the time of hydrothermal cycle increased, part of nanobelts were ruptured into a lot of small polyhedrons, but they still maintained a trend of the previous connection, and some fine nanobelts were interweaved in small polyhedrons. Finally, we successfully prepared a film with a novel 3D nest-like structure, and it had all the characteristics of the hierarchitectures. It had better photoelectric properties than the film with fewer times of hydrothermal cycle. Its photoelectric conversion efficiency reached 3.81%, which is due to a large dye adsorption amount, rapid electronic transmission, and superior light scattering and more electrons transmission paths. An anatase TiO2 photoanode with nanobelt structure was directly prepared on the transparent conductive glass substrate through hydrothermal method, with the time of hydrothermal cycle increased, the novel three-dimensional nest-like structure was formed. Its photoelectric conversion efficiency reached 3.81%, which was due to a large dye adsorption amount, rapid electronic transmission, superior light scattering and more electron transmission paths. [ABSTRACT FROM AUTHOR]

The photovoltaic properties of nanoporous TiO2 films treated by different hydrochloric acid (HCl) concentrations were investigated in dye-sensitized solar cells (DSSCs). The nanostructure of the films was reformed, and the thickness decreased after the HCl hydrothermal treatment, which was observed by SEM analysis. It was found that the electron lifetime, band gap, recombination rate and TiO2 film electron injection efficiency had been changed by the processing when different analysis methods were employed to analyze the experimental results, including OCVD, UV-Vis and Mott–Schottky plots. In addition, the schematic for electron transfer and recombination was shown to discuss the process in clear detail. The performance of the DSSCs based on the different TiO2 films was measured by J–V curves and IPCE. When the TiO2 film was treated by 1 mol L−1 HCl at 180 °C for 3 h, the device had the optimum 7.77% photo-electric conversion performance and 16.04 mA cm−2Jsc. The results suggested that the reformed film nanostructure led to an optimized electron transportation pathway, and the decreased electron recombination and increased injection efficiency resulted in improved DSSCs. [ABSTRACT FROM AUTHOR]