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In this paper, we study the stability of symmetric periodic solutions of the comb-drive finger actuator model. First, on the basis of the relationship between the potential and the period as a function of the energy, we derive the properties of the period of the solution of the corresponding autonomous system (the parameter $\delta$ of input voltage $V_\delta(t)$ is equal to zero) in the prescribed energy range. Then, using these properties and the stability criteria of symmetric periodic solutions of the time-periodic Newtonian equation, we analytically prove the linear stability/instability of the symmetric $(m,p)$-periodic solutions which emanated from nonconstant periodic solutions of the corresponding autonomous system when the parameter $\delta$ is small., Comment: 15pages, 1 figures

We report a highly transparent bipolar resistive random access memory device fabricated by radio frequency magnetron sputtering based on Zr0.5Hf0.5O2 films with an amorphous semiconducting In–Ga–Zn–O films as electrode. The fabricated device gets a high average transmittance of 87.1% in the visible region. We examine the conduction mechanism and calculated the Schottky barrier height at room temperature according to the $I$ – $V$ characteristics. The relaxation behavior of the resistance transients indicates that the oxygen vacancies in the films play an important role in the resistive switching (RS) behaviors. In addition, we demonstrated the schematic energy band diagram to illustrate the RS mechanism.

This paper studies on the sensorless rotating speed detection methods for the single-phase AC series-excited (SACS) motor. The method to solve this problem based on STFT is worked out, and the experiments show that, the results with high precision can be obtained within 15 seconds. The comparison between the methods using STFT and wavelet is also given out. The comparison shows that the method using STFT is better than that using wavelet both in calculation time and precision.

This paper analyzes the disadvantages of the testing system for the single-phase AC series-excited motor (SACSM) and points out the necessity of the study on the no-coupling motor testing system. Then, this paper studies on one of the basic problems of the no-coupling testing system, that is, the sensorless speed detection during the motor testing. The method to solve this problem based on STFT (short time Fourier transformation) is worked out, and the experiments show that, the results with high precision can be obtained within 15 seconds. The comparison between the methods using STFT and wavelet is also given out. The comparison shows that the method using STFT is better than that using wavelet both in calculation time and precision.

We reported that the resistive switching of Ag/In-Ga-Zn-O/Pt cells exhibited self-rectifying performance at low-resistance state (LRS). The self-rectifying behavior with reliability was dynamic at elevated temperature from 303 to 393 K. The Schottky barrier originated from the interface between Ag electrode and In-Ga-Zn-O films, identified by replacing Ag electrode with Cu and Ti metals. The reverse current at 1.2 V of LRS is strongly suppressed and more than three orders of magnitude lower than the forward current. The Schottky barrier height was calculated as approximately 0.32 eV, and the electron injection process and resistive switching mechanism were discussed.