负反馈

The results indicate: 1 closed- loop gain and open-loop gain to meet basic relationship; 2 the stability of feedback is enhanced and output resistance increased. Furthermore, the result of open-loop and closed-loop gain of theoretical calculation is consistent with simulation which is applied by EWB software, which confirmed elementary conclusions and relationships in negative-feedback amplifier quantitatively.

结果表明：闭环增益与开环增益满足基本关系式；引入负反馈后稳定性得以提高，输出电阻增大；同时使用EWB对开环与闭环增益也进行了仿真分析，结果与理论计算一致，从而定量地验证了负反馈放大电路中的结论与关系。

The cutoff frequency is 264 MHz. OTA (Operational Transconductance Amplifier) is realized in pseudo differential topology to maximize the linearity of the filter. Architecture of transconductance enhanced source degeneration is adopted for the VGA to control the gain, together with a source degeneration capacitance to widen the bandwidth.

滤波器采用5阶Chebyshev近似、GC biquad结构，转折频率为264 MHz，OTA采用伪差分结构以提高滤波器的线性度；VGA采用跨导增强型源级负反馈结构来控制增益，并加入源级负反馈电容进行高频补偿以拓展带宽。

In short,the paper illustrates the feasibility of block diagram simulation analysis in negative feedback amplifier circuit.

本文利用EWB软件，采用方框图分析法，对由运放构建的电压负反馈放大电路进行了仿真分析，同时将仿真结果与理论计算加以比较，结果显示两者一致，验证了负反馈放大电路中的基本关系式。1仿真分析1.1电路组成负反馈放大

The producer that application LabIEW has carried on fictitiously the signal and fictitious oscilloscope design ,Moreoer deepen to comprehend the negatie feedback toto the action that the improement amplifier performance respect is taked by means of the test ,Research tension series negatie feedback along with the negatie feedback electric circuit performance index quiz means .

运用LabIEW进行了虚拟信号发生器和虚拟示波器的设计，并且通过实验加深理解负反馈对改善放大器性能方面所起的作用，研究电压串联负反馈以及负反馈电路性能指标的测试方法。

The voltage gan input resistance and output resistance is three parameters of amplifier.

常用的负反馈放大器的计算方法有深度负反馈估算法和方框图法。

Aimming at the fuel control requirement of micro-turbojet,the automobile's electric fuel pump with adaptable improvement is chosen as fuel-feed system.The performance of fuel pump and the technical difficulty of flux control as the speed of pump doesn't be measured are analyzed.Using Philips 83C552 MCU as the main control chip,the system adopts voltage negative feedback combined current compensation instead of rotation speed negative feedback and a PWM convertor to design the flux closed loop control system.

针对微型涡喷发动机的燃油控制要求，选用汽车用电动油泵进行适应性改进作为供油执行装置，详细分析了电动油泵的特性及泵转速无法测量情况下流量控制的技术难点，并以83C552单片机为核心，采用电压负反馈加电流补偿代替转速负反馈、电机通过PWM驱动的方法设计电动油泵流量闭环控制系统。

Resultantly, the individual warm/cold events in ENSO cycle appear to be partially locked to the annual cycle, and also exhibit obvious irregularity both in amplitude and in lasting time.

本文第四章研制设计了一包含海洋表面边界层和大气辐合反馈过程的热带太平洋海气耦合异常模式，进而利用该模式对ENSO循环进行了较为真实的模拟，通过对模式ENSO循环的演变特征及其形成机制的细致分析，建立了-ENSO循环的非线性分析模式，并提出了ENSO循环形成的一种更为客观的理论，指出：1）和观测事实类似，模式ENSO循环确实涉及了三种主要时间尺度过程即LF、QB和AC，其中LF为3-4年主周期振荡，QB占总方差10～20%；2）ENSO循环的正反馈机制是不稳定海气相互作用过程，且这一不稳定过程的发展在暖态中明显强于冷态；3）ENSO循环的负反馈机制在冷暖态中表现不同，在冷态消亡过程中，这种负反馈过程主要表现为西边界反射产生的时滞效应，但在暖态消亡过程中不存在类似的时滞效应，其负反馈过程主要表现为在海气耦合不稳定充分发展时伴随的赤道两侧冷水上翻过程的加强以及非线性过程的衰减作用抑制了不稳定的发展并最终使得系统回复至冷态；4）ENSO循环的3-4年主周期振荡是一非线性系统的自激振荡现象，其形成是线性系统的本征模即准两年振荡通过非线性机制产生的周期加倍所致，其中&单向性&大气辐合反馈加热过程对其形成至关重要；5）虽然年循环过程对ENSO循环形成没有本质影响，但它可明显影响ENSO循环的具体振幅和位相，使得ENSO对季节循环有明显的&锁相&特征，并且也使得ENSO循环在振幅大小和时间长短方面呈现出明显的不规则性。

By locking laser frequency to atomic absorption spectrum through current negative feedback and locking microwave frequency to electromagnetic induced transparency resonance peak through voltage negative feedback, it is realized to lock the clock frequency of this laboratorial desktop experimental CPT frequency standard.

通过采用电流负反馈将激光频率锁定在原子对激光的吸收峰上，电压负反馈将微波频率锁定在电磁感应透明共振峰上，用该物理系统实现了闭环锁定的实验室桌面CPT频标实验系统。

By locking laser frequency to atomic absorption spectrum through current negative feedback and locking microwave frequency to electromagnetic induced transparency resonance peak through voltage negative feedback respectively, the locking of the clock frequency of this laboratorial desktop experimental CPT frequency standard is realized.

介绍了相干布居囚禁原子频标的小型、低功耗物理系统，并应用它开展实现了CPT原子频标的激光锁定、微波锁定方案的实验室研究。通过采用电流负反馈将激光频率锁定在原子对激光的吸收峰上，电压负反馈将微波频率锁定在电磁感应透明共振峰上，用该物理系统实现了闭环锁定的实验室桌面CPT频标实验系统。

Compared the voltage negative feedback wire-feeding speed regulation system supported by current positive feedback with the rotational speed negative feedback regulation system, the equivalent condition of the two systems is obtained. Then, a wire-feeding speed regulation circuit for the CO_2 welding machine is designed based on TL494 chip, which has the self-protective function under the condition of current overloading.

通过对电压负反馈配合电流正反馈的送丝调速系统与转速负反馈调速系统的比较，得出了这两种调速系统的等效条件，并采用电压负反馈配合电流正反馈技术，设计了一种以TL494为核心的具有过电流截止保护功能的CO_2焊机送丝调速电路。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。