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To solve the problem of joint speed and strength of electricity controlled flexible clutch system (DMT) in the buses, the paper proposed a control method of pulse width modulation (PWM) based on the Freescale of 16-bit MC9S12XEP100 microcontroller. Designed the DMT control circuit and used the PID control of exciting current. The test results show that PWM control solved the rapid joint lead to overshoot,...
A novel model for activation energy calculation derived from the Arrhenius Equation is presented in this paper. Firstly, value assignment method is adopted to prove that the calculation error of model 1 is 13%, and the calculation error of model 2 is 1.57% while the calculation error is only 0.29% by using the novel model. The result testifies the higher precision of the new model. Secondly, the stability...
With the development of manufacturing technology and process level, the reliability of DC/DC converter becomes higher and higher, which is a big challenge to the reliability evaluation of DC/DC converter. In this paper, to solve the problem, DC/DC converter is studied by the test of constant electrical stress and temperature ramp stress method (CETRM). With CETRM, time and cost of the test are efficiently...
Fundamentals of current conduction of the AlGaN/GaN HEMTs have been studied under the temperature ranging from 26°C to 250°C. It's found that the maximum drain-source current (IDS) decreases with rising temperature, and the temperature dependent of IDS has a negative coefficient of −0.31 mA/mm · °C. This deterioration mainly cause by decreasing in mobility. And a rise in temperature is accompanied...
Aiming at determining the optical reconstruction rank of singular value matrix in SVD filter, a new method based on noise singular values clustering is proposed in this paper. Variable forward standard deviation (F-Std) has been defined and the mutation point in F-Std is used to separate signal singular values from noise singular values. Experiments have been simulated by some noisy signals using...
Locating the head wave of ultrasonic echo accurately is the basis of measuring the thickness of sediment in drilling hole precisely. This paper presents a method to locate the echo head wave by local signal-to-noise ratio (L-SNR). The original signal is filtered by a parameters constrained Gabor filter and transformed into frequency domain by windowed Fourier transform firstly, and then the L-SNR...
Study EEG signal is an approach to understand the relationship between neurons electron activities and animal's physiological and psychological state. A wireless EEG signal collector is designed in this paper. The collector contains microelectrodes set, front circuit, low-pass filter circuit, data collecting and transmitting circuit, and power supply circuit. When the two microelectrodes are pushed...
A novel method, which enables rapid determination of lifetime for semiconductor devices, is presented based on progressive-stress accelerated degradation test. Through two steps of acceleration: firstly, using process-stress accelerated test to accelerate the parameter degradation; secondly, using the data of 1~5% degradation to extrapolate the data of 10~50% degradation, this method shortens the...
Ever-increasing DC/DC power density and peak temperature challenge its reliability and performance. Thermal simulation and analysis play a significant role in development of new generation of DC/DC package design. This paper presents an accurate and fast approach to simulate the thermal distribution of a DC/DC module. The thermal distribution is simulated with ANSYS, and verified by infrared thermal...
Anti-virus experiment in vitro is a common way to screen and identify antiviral drugs. Most of the cells in the experiments are wall-adherent. Segmenting, recognizing and counting this wall-adherent cells in micrograph successfully can cut down the time and cost of the experiment. It is much difficult to segment this kind of image because of the wall-adherent cells characteristics. In this paper,...
Anti-virus experiment in vitro is a common way to screen and identify antiviral drugs. Most of the cell lines in anti-virus experiments are wall-adherent. The segmentation, recognition and counting this wall-adherent cells in micrograph successfully can cut down the time and cost of the experiment. Because of the wall-adherent cells characteristics, to segment this kind of image is much difficult...
Quadrature decode technology is widely used in high accurate motor monitoring. But by now, the commercial quadrature decoder is not ideal because of its complex structure, high price, unchangeable counter and output interface. In this paper, a method is presented to optimize the quadrature encode signal according to its property, the modules to filter, quadruplicate and distinguish direction and the...
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