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分析了五种模拟电感器 ,阐明了各自的特点及其适应的场合 ,提出了改进模拟电感器性能的具体措施 . 相似文献
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中国的现代设计似乎处在一种语境的缺失中,而本文从对传统图形内在精神的解读、变革后的再生以及中国现代设计的困境出发进行思考,并力图从传统图形中去解说现代设计所缺失的生动境域。 相似文献
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A novel topology of the current-source grid-connected inverter is proposed based on the immittance converter theory. A control strategy of sine-sine pulse width modulation (PWM) is studied. Compared with the traditional current-source inverter, the power frequency inductors and power frequency transformer are replaced with high frequency inductors and a high frequency transformer. Thus, the proposed inverter has advantages of small volume, low cost, low total harmonic distortion (THD), low power losses, high power factor (PF) and simple control. Furthermore, grid voltage cannot influence output current of the grid-connected inverter and the current-source inverter with a high PF that approaches one has been realized. Finally, validity of the theory analysis and feasibility of the control scheme are shown by simulation and experimental results. 相似文献
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<正>初中物理教学大纲中指出:“要培养学生的观察能力,实验能力,思维能力,分析和解决问题的能力”。可见,物理教学要重视能力的培养,而思维能力的培养是各种能力培养的核心,在物理教学中应如何培养学生的思维能力呢?我作了如下的尝试: 相似文献