自动频率控制

Development of OA kneepad : The kneepad density-wave output can be controlled by 2Hz different frequencies to 300 Hz stimulation pulse component, the pulse width of 100 to 150 μ s between the positive and negative output symmetry to the stimulation pulse. The rechargeable mobile phone batteries ( 3.7V) were served as power supply and SCM as timer with automatic shutdown after 30 minutes.

OA护膝的研制：护膝输出的疏密波可控制由2～300Hz不同频率刺激脉冲组成，脉冲宽度在100～150μs 之间，输出正负向对称的刺激脉冲，采用可充电的手机电池(3.7V)供电，单片机定时，30min 自动关机。

Development of OA kneepad: Under the principle of＂treating cold syndrome with hot-natured drugs＂ and ＂treating blood stasis syndrome with promoting blood circulation and removing blood stasis drugs＂,PIC16F630 SCM was served as the core and mainly composed of four parts including the boost circuit, the output, single-chip microcomputer control, as well as electric soft membrane.

OA护膝的研制：根据中医"寒者热之"、"瘀者通之"的治则，以PIC16F630 单片机为核心，电路主要由升压、输出、单片机控制以及电热软膜4 部分组成，通过键盘设定单片机产生不同幅度和频率的动态变频疏密波进行治疗，30min 后单片机内部定时器中断，自动关机。

The pulsed controller, with micro-controller unit as the core, light emitting diodes and keyboard as the man-machine communication interface, has been designed and developed in combination with electronic technology, automation theory and MCU technology.

本文利用电子技术、自动控制理论及单片机技术，设计并制造了直流电焊机双丝脉冲控制器，以单片机为内核，数码管、键盘为人机界面，可以使焊接电压成为在一定恒压基础上，进行一定频率和幅值变化的脉冲电压。

This paper describes a piezoelectric drive circuit which can find the syntonic frequency of motor through scanning frequency region based on computer controlling.

提出了一种基于计算机控制的压电超声马达谐振频率自动搜寻系统。

The tester with DSP core could get excellent results by judging and adopting the different value of voltage and current, programmed amplifying and changing the frequency of sample.

系统以DSP为控制核心，可自动识别并适应不同的电压和电流等级，采用程控放大、变化采样频率以获得优化的阵列测试效果。

Based on mass-spring model, a method of automatic mode-selecting method is presented to solve the difficulties of selecting corresponding modes close to the excitation frequency, in adaptive perturbation for mistuned bladed disks.

摘要针对自适应摄动法在失谐叶盘受迫振动分析中，选择接近激振力频率的相应模态数目难于控制的问题，基于质量－弹簧模型，提出一种自动选择模态的方法。

This paper proposes an self-adaptive speed-accommodating control circuit,which can get the speed-error,and can test the change of frequency of feedback signals of the single phase ac tacho generator through self comparing and automatically corrects the speed.

文章介绍了通过自比较来检测录音机主导轴单相永磁交流测速发电机反馈信号的频率变化，从而获得速度误差，并自动校正转速的一种自适应速度调节控制电路。

Timing, modern communication, navigation and position, and computer auto-control all depend on precision time scale and accurate time synchronization.

精密计时、现代通信、导航定位和计算机自动控制等都离不开精密时间尺度和时间频率测量技术。

The governor is designed with model structure. Closed-loop start-up strategy is applied during running and it realizes three adjust mode-frequency, wicket gate and power.

调速器采用模块结构进行设计，在调节过程中实现了闭环开机控制策略，并可在频率调节、开度调节、功率调节三种调节模式之间自动或手动无扰动切换。

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％。