变换元件

In the new expressions, the definition of fundamental magnifying factor for the 4 kinds of circuits is the same. They are easy to solve A in calculation, without considering the loading effect of feedback network any longer, and an unidirectional conversion can be made; meantime, they can directly describe the effect of every circuit component parameter on closed-loop voltage gain.

新关系式中4种电路基本放大倍数的定义相同，容易计算，不再需要考虑反馈网络的负载作用，而做单向化变换，并能直观描述各电路元件参数对闭环增益A的影响。

The left inverse perfect shuffle, right perfect shuffle and the right inverse perfect shuffle are discussed complementally based on some reports on left perfect shuffle in previous papers.

针对目前已经采用的实现左混洗变换方法的不足，提出了利用微光学衍射元件实现全混洗变换的方法。

This paper discusses a method, which can be used to approximately calculate the equivalent resistance and to approximately calculate the efficiency of different topologies. It could benefit a lot in designing DC-DC converters.

本文提出了一种近似计算等效电阻的方法，其原理是将变换器中各元件的损耗之和等效为输出电阻的损耗，可以简便计算变换器的效率，有助于选择合适的电路。

An immersible transducer is a hermetically sealed stainless steel container which contains a number of transducer elements. These transducers offer the major

浸水式变换器使用一个气密不锈钢容器，里面含有大量变换器元件。

C. Koraн, the formation of a composite filter requires such processes as equivalent network transformations and impedance-level transformations.

在利用所提出的影象参数最少电感元件带通滤波器各种半节来构成复合滤波器时，其复合过程一般比较复杂，通常要经过等效网络变换、阻抗水平变换等步骤才能合并，由于这种类型结构的元件系数计算公式形状较繁，所以更增加了应用时的不便。

The critical part of this sight is a holographic optical elements combined with a lensless Fourier transform hologram and a holographic beam transformer.

瞄准具的核心部件是由一块无透镜傅里叶变换位相全息图和一块全息光束变换器组成的全息光学元件。

With the development of semiconductor devices, the switching frequency of PWM converters becomes higher, which makes PWM converters (mainly high-frequency transformers, inductors and capacitors in converters) smaller, and this will benefit design and application of them. Whats more, higher switching frequency will reduce the audio-frequency noise and improve dynamic response of PWM converters.

随着半导体器件技术的不断发展，PWM变换器所能达到的开关工作频率越来越高，使得变换器(主要是变换器中的高频变压器、电感等磁性元件和电容)的体积和重量越来越小，这有利于PWM变换器的设计及推广应用。

A discussion is given on the possibility of the negative resistance component and its physical properties, set forth the relationship between the negative resistance component and negative impedance converter and applicatio

从变量约束关系出发分析了负阻元件存在的可能性及其物理性质，阐述了负阻元件与负阻抗变换器的关系及其应用。

Some circuits use resonant, quasi-resonant, and/or multi-resonant techniques. However, voltage or current stresses in these converters are higher and require the devices of higher VA rating. Some circuits use passive snubbers or active clamp techniques. However these converters become more complicate. Phase-shift ZVS technique has been used in bidirectional DC/DC converters since it can realize ZVS for all switches without auxiliary switches.

谐振、准谐振或多谐振技术方案，变换器的电压电流应力较高，变频控制增加了滤波器设计的难度；能量缓冲吸收电路或有源钳位电路方案，由于需要增加多个额外辅助元件，增加了变换器的复杂性；全桥相移技术方案，由于主电路无需增加额外元件，只需利用相移控制，即可实现软开关，因此引起关注。

However it can not be widely used in industry because of commutation problem, low voltage transformation ratio and complicated PWM method.

本文介绍了一种新型的矩阵变换器—稀疏矩阵变换器，它具有传统的矩阵变换器的优点：四象限运行；没有直流环节的储能元件和高质量的输入电流/输出电压波形。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。