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This article is concerned with the stability and stabilisation of switched time-delay systems (STDSs) with exponential uncertainty. Based on the Hurwitz convex combination and the energy attenuation principle, an improved state-dependent switching strategy is proposed, which switches to the next modes to obey the minimum energy. This approach fully considers the system dynamic of subsystems, which is more general. Considering the complex switching and delay dynamics, a mode-dependent Lyapunov–Krasovskii functional (LKF) that contains a triple integral term is constructed. The generalised free-matrix-based integral inequality (GFMBII) is used to estimate the integral terms in the derivative of the LKF, and an improved delay-dependent stability criterion is established in the form of linear matrix inequalities (LMIs). Further, to guarantee the stability of the STDSs with a large time-varying delay, a controller that considers the time delay and the exponential uncertainty is designed. Under this controller, a less conservative delay-dependent robust stabilisation criterion for STDSs with exponential uncertainty is established. The validity of the proposed methods is validated by two numerical examples and an application in river pollution control. [ABSTRACT FROM AUTHOR]

The presence of oxygen inhibition effect in radical photopolymerization leads to incomplete curing in the surfaces and affects the final performance of cured material. In this work, the insensitivity of thiol-acrylate system to oxygen was introduced into the upconversion particles assisted near-infrared photopolymerization (UCAP) to overcome the oxygen inhibition effect of acrylate system. The effects of the UCPs concentration, the structure and content of thiol monomers on the oxygen inhibition degree were systematically studied by combining thiols with (meth) acrylate monomers. The ATR-FTIR were used to characterize the polymerization kinetics of monocomponent (meth) acrylate and thiol-acrylate systems in UCAP. The double bond conversion at different depths of the cured material was characterized by Confocal Raman Microscopy. The results show that in the mixed system of secondary mercaptan PE-1 and acrylate monomer EM2261 with 2. Owt% UCPs and 50%-SH molarity, the maximum double bond conversion of 82% was obtained on the surface and over 90% in the deep layer, the oxygen inhibition degree of the surface layer were effectively reduced. [ABSTRACT FROM AUTHOR]