Although the numerous advantages of polymer optical fiber (POF) sensors have been applied in different fields, the measurement consistency and sensitivity of POF evanescent wave (EW) sensors are still affected by its thermal stability and water absorption. Therefore, we perform a study to demonstrate the mechanism of the effect of heat treatments on physical and optical properties of POF EW sensors. We investigate the surface morphology, composition, refractive index, geometry, and weight of the fiber-sensing region subjected to water and vacuum heat treatments. We examine the spectral transmission and transmitted light intensity of POF sensors. We present a theoretical investigation of the effect of heat treatments on the sensitivity of POF EW sensors. The performance of the prepared sensor is evaluated using glucose and Chlorella pyrenoidosa analytes. We discovered that the spectral transmission and transmitted light intensity of the fibers shows little effect of vacuum heat treatments. In particular, the sensors, which subject to vacuum heat treatment at 110 °C for 3 h, exhibit temperature-independent measuring consistency and high sensitivity in glucose solutions in the temperature range 15-60 °C and also show high sensitivity in Chlorella pyrenoidosa solutions.

According to the coupling characteristic of propulsion system and impact system of hydraulic rock drill, deduced the calculation formula of optimal axial thrust for the propulsion system of hydraulic rock drill. On the basics of the calculation formula before, the paper constructed compound driven propulsion system of hydraulic rock drill based on electro-hydraulic proportional pressure-reducing valve and high speed on-off valve, and established its dynamics model. Finally, the paper considered optimal axial thrust as the goal, and adopted the fuzzy PID control strategy to realize on-line, intelligent control to axial thrust of the propulsion system of hydraulic rock drill. Through mathematical modelling and simulation study show that fuzzy PID control method has its advantages as the fast response follow by target, high control precision, and small fluctuation, and provided theory reference and technology method for intelligent control of the propulsion system of hydraulic rock drill.

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As the obtained data in many practical applications tend to be uncertain or inaccurate, the conventional modeling methods characterized by the deterministic model for this type of data have become undesirable. Taking linear programming, the T-S fuzzy model and some ideas from 1-norm minimization into consideration, a novel method identifying interval fuzzy model (INFUMO) consisted of the upper and lower T-S fuzzy model (referred to as f U and f L ) has been studied in this paper. In order to solve the INFUMO, optimization problems based on minimizing 1-norm with respect to the approximation error corresponding to f U and f L are constructed. Finally, the optimization problems are solved by the linear programming and INFUMO is thus constructed. To demonstrate its effectiveness, the proposed method is applied to identify the interval T-S model of static and dynamic nonlinear model with noise. The proposed method can not only deal with uncertain data to be usually modeled as the deterministic model, but also has better robustness.