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The cutting temperature and cutting force are some of the main factors that influence the surface quality of carbon fiber-reinforced polymer (CFRP). However, few investigations have been done on cutting temperature because it is difficult to capture the dynamic response of the temperature measurement system. Degradation of resin will occur within the machined surface or surface layer as the temperature exceeds the glass-transition temperature of the resin matrix. In this research, the relationship between cutting parameters and cutting temperature, cutting force were developed by response surface methodology (RSM). The experiments were designed using the tool-workpiece thermocouple technique. Taking into consideration the effect of the glass-transition temperature, the influence of cutting force and cutting temperature on surface quality of CFRP was analyzed. Analysis results showed that Spindle speed is the key parameter which influenced the cutting temperature while feed rate is the key parameter which influenced the cutting force in milling of CFRP. When the cutting temperature exceeds the glass-transition temperature (T g ), the matrix cannot provide enough support to the fibers, and the machining quality of composite material is poor.

a b s t r a c tThe main purpose of this paper is to analyze the stability and error estimates of the local discontinuous Galerkin (LDG) methods coupled with implicit-explicit (IMEX) time discretization schemes, for solving one-dimensional convection-diffusion equations with a nonlinear convection. Both Runge-Kutta and multi-step IMEX methods are considered. By the aid of the energy method, we show that the IMEX LDG schemes are unconditionally stable for the nonlinear problems, in the sense that the time-step s is only required to be upper-bounded by a positive constant which depends on the flow velocity and the diffusion coefficient, but is independent of the mesh size h. We also give optimal error estimates for the IMEX LDG schemes, under the same temporal condition, if a monotone numerical flux is adopted for the convection. Numerical experiments are given to verify our main results.

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These data imply that isoflurane might induce caspase-3 activation by causing ER stress through RyRs, and dantrolene could attenuate the isoflurane-induced ER stress and caspase-3 activation. Further investigations of the potential neurotoxicity of isoflurane are needed.