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Thermochromic VO 2 thin films are fabricated by using high power impulse magnetron sputtering at room temperature. In order to increase the crystallinity and transparency of VO 2 thin films, a barrier layer of TiO 2 is deposited on the glass substrate. Then TiO 2 /VO 2 stacks are post-annealed at a temperature of 500 °C for 3 min. The transmittance properties as functions of TiO 2 and VO 2 thicknesses are discussed. The effects of TiO 2 thickness on the strain state of ( 011) and ( 211) planes of monoclinic phase are studied. The laminated film shows satisfactory optical properties with an excellent solar regulation efficiency (ΔT sol = 10.2%) and an acceptable luminous transmittance (T lum = 41.1%) in a low-temperature state. Good endurance property is demonstrated using a thermal stress cycle of 25 °C/85 °C for 100 times.

Thermochromic VO2 thin films are fabricated by using high power impulse magnetron sputtering. The effect of the duty cycle with different on/off time ratios on the thermochromic properties is investigated. Though the transmittance increases with decreasing duty cycle, a moderate duty cycle is suggested. It is found that V2O3 crystallinities appear at a low duty cycle, while the inter-diffusion between TiO2 and VO2 layers becomes worse at a high duty cycle. In this study, the VO2/TiO2/glass stacked structures reach a solar regulation efficiency (ΔTsol = 9.5%) and an applicable luminous transmittance (Tlum = 43.1%) in a low-temperature state under the duty cycle of 2.5%. The crystalline behavior of the monoclinic phase shown in the x-ray diffraction pattern is further examined by a high resolution transmission electron microscope. The changes in binding energies of V 2p and O 1s orbits are compared throughout the films. The thermochromic properties as a function of TiO2 thickness are also discussed.

This paper proposes an adaptive fuzzy controller to balance a constructed two-wheeled vehicle at upright position. The dynamical model of the vehicle-LEGO Mindstorms NXT is first established. Based on the model developed, an adaptive fuzzy controller is then illustrated. Adaptation laws are derived from the Lyapunov stability analysis, so that the system tracking performance and the error convergence can be assured in the closed-loop control system. Finally, we apply the PD (Proportional Derivative) controller and the proposed controller to balance the two-wheeled vehicle to compare the system performance.

In this study,MFIS (Metal/Ferroelectric/Insulator/Semiconductor) capacitors whose structure is Al/BFO+Nb/HfO2/p-Si are investigatedby using Taguchi Method. The effects of leakage current, memory window, and signal-to-noise ratio (S/N ratio) are discussed by different process conditions. As a result, the leakage current and memory window indicate the better performance on th same process condition. The better conditions of this MFIS capacitoroccur in rapid thermal annealing (RTA) at 700°C, 5W direct current (DC) power of Nb sputtering and 15 of argon-to-oxygen ratio for laekage current and memory window.Oxygen vacancies were reduced bydoping niobium (Nb) that Nb ions replace ferrum (Fe) ions with RTA at 700°C. The more Nb dopesthe more Nb ions replace Fe ions. Butthe excessive Nb induces to increase the leakage current and reduce the memory widow.