查询词典 direct

The thesis first probably explains BrushLess Direct Current Motor, and discusses the related control methods, explains the background and Meaning of back electromotive force which is used in the thesis.

本文首先对无刷直流电机进行了概述，并对其相关控制方法进行了讨论，说明本文所采用反电动势法的背景和意义；接着论述了无刷直流电机基本组成环节、基本工作原理、运行特性和传递函数，然后是详述本文研究的重点：基于反电动势法的MATLAB调速系统的仿真以及基于反电动势法的DSP控制系统的实现。

In order to eliminate direct current drift and saturation problems of pure integrator for back electromotive force,an improved programmable low-pass filter rotor flux estimator was proposed to replace the pure integrator.

为了有效抑制反电动势积分环节所存在的直流偏移和积分饱和问题，采用一个截止频率可根据输出频率进行自调整的低通滤波器来代替传统电压模型磁链观测器中的反电动势积分环节。

When a rotating voltage vector is injected to the motor at standstill, there is a microinching when the voltage phase is line to the direct axis of the motor. Then the current will decrease due to the back electromotive force. The initial mover position is identified by this change.

电压相位和电机直轴重合时，产生的电磁推力超过负载阻力，电机有一微动，由于反电势的作用电流就会降低，通过检测电流矢量的变化来估计动子的初始位置。

The thesis first probably explains BrushLess Direct Current Motor, and discusses the related control methods, explains the background and Meaning of back electromotive force which is used in the thesis.Then the thesis expounds the basic component parts,the basic running principle,the running characteristic and transfer function of the BLDCM.And then the thesis detailedly dissertates its research pivot: the simulation of BLDCM system in MATLAB based on the method of Back-EMF and the control system of Digital Signal Processor based on the method of Back-EMF.

本文首先对无刷直流电机进行了概述，并对其相关控制方法进行了讨论，说明本文所采用反电动势法的背景和意义；接着论述了无刷直流电机基本组成环节、基本工作原理、运行特性和传递函数，然后是详述本文研究的重点：基于反电动势法的MATLAB调速系统的仿真以及基于反电动势法的DSP控制系统的实现。

A novel method was proposed for the direct determination of biomarkers,such as n-alkanes,terpanes and steranes in crude oil by GC/MS coupling with backflush cutting technique and micro-fluidic splitter.

研究了一种反吹切割微流控装置气质联用技术直接分析原油中的正构烷烃类、萜烷类、甾烷类生物标志物的新分析方法。

Secondly, the direct demodulation detection system of 8mm wave band 32-channel on the background of millimeter-wave focal plane imaging is built, according to millimeter-wave passive detection theory, at the same time, the principle experiment is carried out, and the basic theory of millimeter-wave detection are confirmed.

其次，根据被动毫米波探测理论搭建了以毫米波焦平面成像为应用背景的8mm波段32通道直接检波式探测系统，并进行了原理性实验，验证了被动毫米波探测的基本理论。

Gun used to direct attention to timely cease-fire (shortcut "Backspace").

用直射炮时要注意适时停火(快捷键"Backspace")。

objective comparison of 120 example cervical wecretion directly smear and culture.methods one sterile swab directly smear;gram stain;bacterioscopy, others swabs inoculate chocolate plate;blood plate;shaborose plate;culturing 24 hours then identification.results ng and bv directly smear isolates rate higher than culture;butfung culture isolate rate higher than direct smear to bacterioscopy.conclusion cervical wecretion directly smear to bacterioscapy has rapidly and simply diagnostic value

摘 要］目的：比较120例妇科宫颈分泌物直接涂片镜检与培养结果的分析。方法：宫颈分泌物直接涂片、革兰染色、显微镜检与宫颈分泌物接种于巧克力板、血平板、沙氏板进行培养和鉴定。结果：对分泌物中的致病菌而言，g-双球菌和阴道加德纳菌的直接涂片镜检阳性率较培养高；霉菌的培养阳性率较直接涂片镜检率高。结论：妇科宫颈分泌物直接涂片镜检具有快速、直观、简便的诊断价值。

In recent years, high voltage direct current system is rapidly developed, but harmonic pollution is produced and becomes badly, harmonic measurement by true is the precondition and sticking point of restraining harmonic.

近些年来，高压直流输电得到了快速的发展，电网的谐波污染也日趋严重，实时、准确地测量谐波电流信号是有效抑制谐波电流的前提与关键。

The value of the area is direct proportional to the number of baffler and the parameter of free area ratio, but it increases exponentially with the diameter of the column and the pulsed amplitude.

峰面积值与脉冲萃取柱的板数和板开孔率参数成正比，与柱径和脉冲振幅成指数关系。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。