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In order to eliminate the influence caused by the nonminimum phase characteristic of a common Boost DC／DC converter, Viswanathan K has proposed a novel tristate Boost DC／DC converter. For enhancing performance, the statespace averaging model of this converter was first presented in this paper. Due to the nonlinear nature in this model, an inputoutput feedback linearization technique was adopted, and a complete controllable linear system was obtained. Then a statefeedback control strategy was designed based on this linear system. Simulation results show that the proposed control strategy can assure constant output voltage in a wide range, so as to realize the stability of the system during large fluctuation of power supply and load disturbance. Good dynamic performance can also be achieved.

针对 Viswanathan K为消除普通BOOST DC／DC变换器的非最小相位特性而提出的三态Boost DC／DC变换器，为进一步提高这种电路拓扑的性能，在建立了变换器状态空间平均模型的基础上，针对其多变量、非线性特点，采用输入输出线性化将其转化为一个完全可控的线性系统，在此基础上应用现有成熟的线性控制策略进行了控制系统的设计，并且采用MATLAB进行仿真验证，结果表明：这种非线性控制策略可以确保输出电压在大范围内恒定可调，且即使存在大范围扰动(输入电压和负载变化均较大)的情况下，系统也可以确保稳定性和良好的动态性能。

A novel phase-shifted zero-voltage and zero-current switching PWM DC/DC full-bridge converter is presented in this thesis, which is based on the groundwork of summarization of the development of Power Electronics in recent years and lucubration in theoretical basis of modern high frequency soft switching power convert technique and analysis of operation principle, characteristic of the circuit and inherent drawbacks of the traditional phase-shifted zero-voltage switching PWM DC/DC full-bridge con...

本文在对近年来电力电子学科的发展高度综述和对现代高频软开关功率变换技术理论基础深入研究的基础上，对传统的移相控制ZVS PWM DC／DC全桥变换器的工作原理、电路特性、存在的缺点进行了分析，在此基础上提出了一种改进型的移相控制ZVZCS PWM DC／DC全桥变换器。

This paper analyzes the numerical control DC constant current source system design needs, expounded numerical-controlled DC constant current source of the hardware and software design principles, instructed the numerical-controlled DC constant current source circuit of the module function and design ideas, completed the numerical-controlled DC current source of all design, and the circuit is complete and procedures.

本文主要分析了数控直流恒流源系统的设计需求，阐述了数控直流恒流源的软硬件的设计原则，介绍了数控直流恒流源各模块电路的功能及设计思路，完成了数控直流恒流源系统的全部设计，给出了完整的电路图和程序。

In the proposed device to remedy the defect that overhigh withstand voltage of thyristors used in converter are needed due to the overhigh DC link voltage, a method to control DC link voltage is put forward, that is, a special control logic for full-controllable switching elements is designed to make them equivalent to half-controllable switching elements which are naturally turned on and turned off by triggering, then connecting such a half-controllable switching element in series with DC link the defect of overhigh DC link voltage is effectively solved.

为了克服该装置直流母线电压过高，因而对逆变器开关管耐压要求过高的缺点，提出一种对直流母线电压进行控制的方法。对全控型开关器件设计一种特殊的控制逻辑，使其等效为一个自然导通、触发关断的半控型开关器件，将该半控型开关串联在直流母线上，有效解决了直流母线电压过高的问题。

These topologies, combining advantages of single switch and dual switch forward DC/DC converters, are obtained by applying several classical reset schemes to dual switch forward DC/DC converter.

这一系列变换电路是将单管正激变换电路的几种典型的复位方式应用到双管正激变换电路中得到的。

So analyzing the phenomenon of unstable action and subharmonic of DC/DC converter from the angle of linear theory and definiteness theory can not meet the increasing requirement of control performance of DC/DC converter.

因此，仅仅从线性论和确定论角度去分析DC／DC变换器中的不稳定及次谐波现象已不能满足对DC／DC变换器控制性能日益提高的要求。

The appearance of brushless DC motor brought the development of EPS a new opportunity. BLDCM does not only possess almost all the advantages of a DC motor, but also has a series unique advantage. The way of taking the place of DC motor by a permanent magnet coreless brushless DC motor gives a totally new method for the development of EPS in the future.

无刷直流电机的出现为电动助力转向的发展带来了新的机遇，它不仅具有几乎直流电机的全部优点，同时还具有一系列无可比拟的优势，特别是采用无铁心永磁无刷直流电机代替普通直流电机，不失为今后电动助力转向发展的一种全新思路。

Lipopolysaccharide was added to induce the ES-DC maturation.The matured ES-DC was harvested 24 hours later to identifying with morphology and transmission electron microscopy.The phenotype of matured ES-DC was analyzed by flow cytometry and compared with the immatured ES-DC.

用磷酸脂多糖促进DC的成熟，收获细胞后观察细胞形态及摄片并做扫描电镜检查，分析细胞表型并与不成熟DC细胞表型做对比，异体淋巴细胞增殖实验行功能检测。

Result The cultured DC from mouse bone marrow displayed the typical morphological characteristics of DC. Immature DC, which had high expression in CD11c and low expression in MHCⅡ and CD86, could phagocytize antigen. Mature DC, which had high expression in CD11c, MHCⅡ and CD86, could stimulate allogenic mixed lymphocyte proliferation.

未成熟DC的细胞表型为CD11c、MHCⅡ、CD86，具有极强的抗原吞噬能力；未成熟DC经LPS刺激培养后可转变为成熟DC，细胞表型为CD11c、MHCⅡ、CD86，可显著刺激同种异体混合淋巴细胞增殖。

Considering the switch of the DC control mode, a new load margin solution is presental that is to solve the maximum load incremental under each DC control mode separately and add them together. The method is characterized by its convenience of considering varialle constraints of DC system and adjustment of DC operation mode.

交直流系统直流控制方式会发生调整，提出分段求解负荷裕度的方法，即分别用内点法求解系统不同直流控制方式的最大负荷增量再求和，该方法能方便考虑直流变量约束及运行方式的调整。

Vishnu entered a dark fourth dimensional dream that did not support his field or continued life.

毗瑟挐进入了一个第四密度的黑暗梦想，那里并不支持他的能量场或继续生命。

Leaders and decision-making persons use it to collect the data, including the information of unit work, handing in fee, oweing fee, prepaying fee,changing and afterpaying and account transfering of joining-insurance employee, and account paying of all kinds of insurances from hospitalization insurance institutions.The collected data is picked up, organized, switched and showed to user.

该子系统主要面向各级领导、决策分析人员；从各个医疗保险经办机构和定点医疗机构采集数据，包括在各个医疗保险经办机构处理的单位办公信息，单位缴费、欠费、预缴费信息，参保职工变更信息，参保职工增减变动信息，参保职工补缴信息，参保职工帐户划拨信息：包括各定点医疗机构处理的各险种帐户支出信息，各险种的统筹金支付信息等；将采集的数据提取，组织和转换，然后展示给用户。