查询词典 frequency modulation

Reservoir bed is distinguished by providing the information about resistivity of formations using Electromagnetic Propagated Resistivity Logging method with several mega-hertz operation frequency. The information of dielectric constant of invaded zone is provided using Ultrahigh-frequency Electromagnetic Wave Logging method with above 200 mega-hertz operation frequency, which has no enough radial investigation depth but has a good vertical resolution.

几兆赫兹电磁波传播电阻率测井通过提取地层电阻率的信息来判别油层，以SPPRRYSUN公司源频率为2MHz的EWR-3D测井仪为代表。200 MHz以上的超高频电磁波传播测井具有很高的垂向分辨率，但探测深度太浅，基本上只能反映侵入带介电常数的信息，SCHLUMBERGER公司已推出源频率为1 。1GHz的EPT测井仪。

According to the mine shaft tunnel to the microwave frequency band in the certain degree to the channel characteristic, the radio frequency selects the microwave frequency band 433MHz to make the carrier, enables the wireless signal to carry on the effective dissemination in the line of sight distance, has the transmission stability to be good, external interference small merit.

根据井下隧道对微波频段在一定程度上相当于通道的特点，射频选用微波频段的433MHz做载波，使无线信号能够在视线距离内的进行有效传播，具有传输稳定性好，受外界干扰小的优点。

By parameter(tower total height, shell thickness, meridional curvature) analysis of cooling-tower natural frequency, we find that, the basic natural frequency of cooling tower is sensitive to the top meridional curvature, an approximate formula is proposed based on the parameters, which can estimate the basic natural frequency of cooling tower.

通过对冷却塔自振频率的参数分析，如塔体整高、塔壳厚度、子午线曲率等，发现基础频率对上部子午线曲率较为敏感，并给出了用于估算大型双曲冷却塔基础频率的三参数公式。

This paper introduced the parameter frequency response method,developed ship rolling frequency response function equipped with two U-tube anti-rolling tanks with different natural frequencies,analyzed the tank parameters relative to rolling frequency response amplitude,and researched the effect of tank parameters on the ship rolling amplitude.

本文给出了参数频率响应法，推导了装备两个具有不同固有频率的被动式U型减摇水舱的船舶横摇频率响应函数，分析了影响船舶横摇频率响应幅值的水舱参数，通过仿真详细研究了水舱参数对船舶横摇减摇的影响。

Type DPT250D variable-frequency speeding blister packing machine uses Taiwan Taida frequency converter. The frequency is as twice as other same machines and is applicable for different specs of tablets, sugar-coat pills, capsules, CAP, and abnormal tablets and granules.

DPT250D变频调速泡罩包装机，采用台湾台达变频调速、是同类机型效率的一倍，适用各种不同规格的素片、糖衣片、胶囊、胶丸及异形片粒状等药品。

Adjust the pressure of the impact system steplessly, the strike energy of the hammer will also shift steplessly. When the pressure is higher, the strike energy is higher. When the pressure is lower, the strike energy is lower. Adjust the oil flow of supply pump steplessly, the strike frequency will also shift steplessly. When the flow is more, the strike frequency is higher. When the flow is less, the strike frequency is lower.

从而可通过无级调节控制冲击系统的压力，无级调节控制冲击器的冲击能，压力高时冲击能大，压力低时冲击能小；通过无级调节控制油泵供给冲击系统的流量，无级调节控制冲击器的冲击频率，流量大时冲击频率高，流量小时冲击频率低。

Based on the research on the theory and technology of dual-PWM variable frequency AC motor control, a design of dual-PWM variable frequency AC motor control system which has factor control loop rectifier and slip frequency speed regulator is proposed.

本文在总结和研究当前双PWM变频调速基础理论和常见技术的基础上，设计并研究了一种基于DSP的整流侧功率因数闭环、逆变侧转差频率控制的双PWM异步电机变频调速系统。

Keyboard function set through waveform type,frequency,amplitude,duty cycle,and other parameters of a signal to the microprocessor 89C51 control,MAX038 generated by the various signals,In this process,four-channel signal through D/A converters have simulated voltage and current,It transported up through the analog signal amplification,it enters the frequency MAX038 coarse-IIN,fine-tuning FADJ end,the duty cycle control-DADJ. In its COSC port received a three relays and oscillation frequency capacitance as a choice.

通过键盘设定函数波形种类、频率、幅度、占空比等参数的一个信号进入单片机89C51控制，由MAX038产生各种波形信号，在此过程中信号通过四通道D/A转换器产生模拟电压和电流，它再通过运放将模拟的信号放大，它进入MAX038的频率粗调端IIN、微调端FADJ、占空比控制端DADJ、在它的COSC端口接一个继电器和三个振荡电容作为频率选择。

In this paper, based on the frequency-domain processing model of the multi-polarization, low frequency UWB SAR system, with the consideration of the low frequency UWB electromagnetic scattering characteristics of the calibrators, the polarimetric calibration method is proposed.

该文基于多极化低频UWB SAR频域处理模型，考虑了极化校准中定标体的低频超宽带电磁散射特性的问题，给出了极化校准方法。

The three-dimensional models are successfully imported to ADAMS software through the special interface MECH/PRO, and then the virtual prototype models are founded by toolbox of ADAMS to apply forces and constraints to the parts of the models. The dynamic simulation of the multi-rigid-body rifle model is carried out under the condition of the single shoot by the low firing frequency, high firing frequency and superhigh firing frequency when the rifle model is fixed on the ground, then the dynamic simulation of the multi-rigid-body man-weapon system is operated under the conditions of single and repeating shoots.

通过Pro／E和ADAMS的接口MECH／PRO将三维实体模型顺利导入ADAMS中，并对高频点射步枪和人枪系统施加约束和力，建立高频点射步枪和人枪系统的虚拟样机模型，并且对高频点射步枪及人枪系统进行了较为系统的多刚体系统动力学分析和研究，分别对高频点射步枪固定状态下次高频、高频和超高频点射过程进行了多刚体系统动力学的仿真，在此基础上对高频点射步枪人枪系统点射和连发进行了仿真。

I can not negligent, he should do what?

我不能不在意了，他要做什么呢？

It is very dangerous to swim in the river alone.

一个人到河里游泳是很危险的。