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An experimental investigation of the thermal characteristic of the LED chip and the sensitivity of illumination with thermal substrate is discussed in this study. An optimum thermal diffusion area to the heat flux of LED system is also conducted. Results show that a red LED chip has lower electrical resistance, and therefore has lower power consumption than that of green and blue LED chips. Given these three colors of lighting LEDs, the red LED chip is more sensitive to the thermal environment. A red LED's lighting illumination is decreased almost 12% when the substrate temperature difference is increased to 25 °C. Under the same condition, an LED's illumination experiences only a 2 to 2.5% reduction for the green and blue LED chip.Thermal diffusion area results show a close correlation between thermal diffusion ratio and LED substrate temperature. If the upper limit LED substrate temperature is set at 50 °C and the thermal diffusion ratio approximates 72 cm 2

Radio frequency identification (RFID) technology has been widely used in electronic payment, security systems, and so on. This paper presents an adaptive RFID indoor location sensing system based on received signal strength indication (RSSI) method. A wireless network platform is integrated. A fuzzy neural network architecture is developed to adaptively tune the environmental parameter. The proposed method possesses the advantage of active readers and tags such that long-distance transmission is fulfilled. The positioning accuracy is significantly improved comparing to those used the traditional passive readers and tags. The number of readers and tags is also reduced.

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This paper presents a robust proportional-derivative (PD) based cerebellar model articulation controller (CMAC) for vertical take-off and landing flight control systems. It is known that PD control is a simple and effective control method. However, it does not ensure the robustness if it is used alone for uncertain systems. CMAC can be used for robust control. However, it requires training patterns for tuning some weighting factors. A novel CMAC incorporating with a PD controller design is proposed in this paper. Successful on-line training and recalling process of CMAC accompanying the PD controller was developed. The advantage of the proposed method is mainly the robust tracking performance against aerodynamic parametric variation and external wind gust. Even when the PD controller is not designed well, the CMAC is capable of doing a robust tracking control through on-line recalling and training procedures.