查询词典 radio frequency

This invention utilizes multiplier frequency of picture frequency to reduce the interference between picture frequency, to recognise the warp of the inverter switch frequency and to ensure this warp.

本发明利用图像频率的倍增频率，一方面减少与图像频率间的干扰，另一方面识别反相器开关频率的偏差，并保障其偏差。

Frequency Regulation Frequency regulation is a measure that states the difference between no-load and full-load frequency as a percentage of full-load frequency.

频率调整率频率调整率是指空载和满载之间频率的差别与满载频率的百分比。

The oscillation performance of jet, as oscillation frequency, is the essential data for designing the fluidic device, which is also the key factor that influence the coupling effect of fluidic device and receiving tube. This paper does experiment on the oscillation availability and frequency of feedback jet-oscillation gas wave refrigeration. As a conclusion, the jet oscillates only in a certain range of geometrical sizes and operating conditions. Under the condition of high pressure ratio, the frequency of the jet"s oscillation is only affected by the feedback tube"s length and chamber remarkably. Under the condition of low pressure ratio, the frequency descends with rise of the pressure ratio.

本文将跨音速正反馈射流振荡器与接受管耦合，对耦合后的射流振荡气波制冷机的可振性、振荡频率以及它们的影响因素作了实验研究，得出如下结论：射流只在一定的操作条件和几何结构尺寸范围内才能稳定振荡；射流的振荡频率在较高压比下只受反馈管长和反馈管容腔大小的显著影响，在小压比下随压比的增大而增加；其它结构尺寸和操作条件只影响可振性。

DG1000 operates direct figure to synthesize science and technology, the random that can output an user to be defined oneself is undee, have rich input output, and frequency meter of high accuracy, broad frequency band, frequency limits 100MHz arrives 200MHz, frequency resolution achieves 6 / second.

DG1000操作间接数字分解科技，可输出用户自界说的任意波形，领有丰硕的输入输出，以及高精度、宽频带频率计，频率规模100MHz到200MHz，频率分辨率达到6位/秒。

In this paper, on the basis of the description of the pile-driving process and the dynamic analysis of the pile and the HSPD, the relationship between the frequency and the pile-driving force has been established under the conditions of the pile strength and the HSDP working requirements. The frequency character of the ZYB200B HSPD system has been analyzed quantitatively in the vibrancy pile-driving process, therefore the frequency range and the best available frequency have been obtained.

本文首先通过对压桩过程的描述和桩与液压静力沉桩机的力学分析，确立了液压振动压桩在桩的强度条件下和液压静力沉桩机工作要求下的压桩频率与压桩力幅值之间的关系；定量分析振动压桩时系统的频率特性，得出了ZYB200B型液压静力沉桩机振动压桩时压桩频率的取值范围和系统能得到的最佳频率值。

A novel quasi-constant frequency hysteresis PWM control approach is presented in this paper. Frequency feedback is introduced in hysteresis current control to stabilize switching frequency. Comparing with the common used constant frequency current mode control, the new approach has better stability, faster transient and higher precision, as well as elimination of sub-harmonic oscillation.

摘 要：本文提出了一种新的准固定频率滞环PWM电流控制方法，该方法在滞环电流控制的基础上，引入频率反馈控制，使开关频率基本固定，解决了目前广泛使用的固定频率电流控制方法具有的次谐波振荡的问题，并且具有稳定性好、相应速度快、控制精度高的优点。

On the basis of the characteristics of line boundary, this paper analyzes the different features of internal and external faults. The difference is that the ratio of high frequency to low frequency components in case of one external fault is less than that in case of the same internal fault, in which high frequency is in the band of line trap and low frequency is within 1~10kHz.

在线路边界频率特性的分析基础上，深入地分析了区内外故障时的特征差异：就某一类故障而言，区外故障时反行波中高频分量与(1~10kHz内的)低频分量的比值显著小于区内故障时的比值。

This experiment counts based on the direct digital frequencysynthesis the basic principle, fully II and hardware LT - IV testedthe box using ALtera Corporation's FPGA chip FLEX10 in softwareMaxplus in the platform to complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the Oscilloscope , completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

帮忙翻译一下，谢谢本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

This experiment counts based on the direct digital oscilloscope frequencysynthesis the basic principle, fully II and hardware LT - IV testedthe box using ALtera Corporation's FPGA chip FLEX10 in softwareMaxplus in the platform to complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the oscilloscope, completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital oscilloscope tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

帮忙翻译一下，谢谢本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

To complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the oscilloscope, completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

Listen,point and check your answers.

听，指出并且检查你的答案。

Warming needle is one of effective treatment methods for knee arthralgia aggravated by cold,and it is simple,safety,so it should be developed in clinical acupuncture and moxibustion extensively.

但以本院科针灸门诊在2005年1月—2006年6月期间共收治膝痛患者100余例，经过临床的诊断后，其中施以温针治疗的48例，疗效显著，报道如下。1临床资料本组病例48