查询词典 frequency conversion

In this paper,the necessity of frequency tracking in ultrasonic cleaning equipmens is discussed.Based on introduction on the principle of the mian circuit of the ultrasonic power supply for cleaning equipmens and the principle of PLL,the output frequency of 74HC4046 is changed by a single chip measuring the phase difference between volage and current.The software of adaptive tracking technique with varied frequency steps is completed.

讨论了超声波清洗机中自动频率跟踪的必要性，在介绍超声波清洗机的主电路原理、PLL锁相环原理的基础上，利用单片机检测超声电源负载的电流、电压的相位差，从而改变74HC4046 的输出频率，完成了变步长频率跟踪软件设计。

As the same section is concerned, near the bottom the maximum value of frequency appear within 1mm of bubble size, towards the water face this value tend to decrease, yet the corresponding size turns to increase; in the same time, the frequency is concentrated near the bottom and deconcentrated near the water face; under the experiment condition, the maximum frequency of the total section approximately appear at 0.5mm size; mean bubble size access 0 at bottom and increase acceleratively towards water face where tend to be infinite; total number increase during developing of aeration, and become steady when reach wholly developed area; on the same section, the total number in unit time tend to increase at first and decrease then, along the water depth.

对于同一断面，靠近槽底的测点气泡个数分布最大值出现在气泡尺寸小于1mm的范围内，朝水面方向各测点气泡个数分布最大值呈减小趋势，而其对应尺寸则呈现变大趋势；在靠近槽底，个数分布表现得比较集中，而在水面附近气泡个数分布曲线表现得低而平缓；实验条件下，整个断面上的气泡个数分布的最大值大体上出现在尺寸为0.5mm的地方；气泡平均尺寸在槽底处接近于0而朝水面方向迅速增大，且越接近掺气水流的水面，增加速度越快，最终趋于无穷大；气泡总数在掺气发展区内是沿程增加的，当掺气水流发展到一定程度后气泡总数就基本保持不变了；在同一断面上，各测点单位时间内的气泡总数随高度呈现出先增加后减小的趋势。

Demodulates the FM modulated signal Y at the carrier frequency Fc. Y and Fc have sample frequency Fs. FREQDEV is the frequency deviation of the modulated signal.

Josephus 问题的解答。n个孩子围成圆圈，选任一个数m，从第一个孩子开始数，数到m停止，这个孩子离开，再从第一个开始数，直到剩下一个孩子。

The study about the flux and index of gamma-ray loud blazars show:(1)there is significant correlation between the luminosities in gamma-ray and VLBI radio energy band;(2)there are strong anticorrelarions among the observed indices of soft X-ray, hard X-ray and gamma-ray. For the FSRQs, the whole X-ray emission was contributed by synchrotron self-Compton emission, for the HBLs, the X-ray emission was dominated by synchrotron emission while the soft X-ray emission is dominated by synchrotron emission and the SSC emission dominate the hard X-ray energy band for LBLs;(3) there are strong radio-radio and radio-optical flux correlations for the quasar 3C 273. The higher frequency emission leads those in lower frequency. The multi-band complex indices strongly correlated with the high frequency flux which implies that the object is becoming bright when the energy spectrum is harden.

通过对γ噪Blazar天体的谱指数、流量的相关研究，发现（1）51个样本blazar的γ射线光度与VLBI光度之间存在显著相关；（2）软X、硬X以及γ波段的观测谱指数之间存在较强的反相关，对FSRQs，无论是硬X射线还是软X射线的辐射都是逆康普顿辐射的贡献，而对于HBLs来说，则是同步辐射的贡献，对LBLs，在软X射线波段以同步辐射贡献为主，在硬X射线能区以逆康普顿贡献为主；（3）3C 273的射电各个波段以及光学之间存在强相关，高频辐射一直领先低频辐射，3C 273的多波段复合谱指数和高频流量之间存在强的反相关，意味着当能谱变硬时对象变亮。

The FEM, whose process is very *** and is fit to deal with complex boundary condition, is used to simulate the frequency-domain IP. Studying the characters and laws of IP\'parameters under different measuring devices and undulate topography will provide scientific references and basis and reduce the multiplicities of interpretation. It is will be an attempt and exploration.Because of the frequency of the exciting currents is usually between 10-2～102 Hz, the vector A can be seen is not change with the time and the EM effect can be ignored in the low frequency.

双频以及伪随机三频激电法以它特有的轻便、快捷、高效率等特点在有色金属矿躲勘探领域里获得了广泛的应用，运用有限单元法的推导过程简单、适合处理复杂几何外形等特点来对双频以及伪随机三频激电法进行正演数值模拟，分析和研究了激电参数在不同丈量装置、模型参数和起伏地形情况下的特点和规律，为后续的资料解释提供科学的依据和参考，为减少地球物理中的多解性做一些有益的探索和尝试。

At first, setting up the arith relation between the signal input and the signal output of the generalized multi-carrier system of the Discrete Fourier Test spread-spectrum; then setting equilibria parameters of the frequency field equilibria subcarrier of the generalized multi-carrier system of the DFT spread-spectrum according to channel frequency response, channel noise variance and equilibria method; then calculating average power of useful signal, interferential average power between signals as well as noise variance of the generalized multi-carrier system receiving terminal of the DFT spread-spectrum according to the arith relation as well as the frequency field equilibria parameter, and recomputing available signal information noise ratio, so as to calculate the available signal information noise ratio of the generalized multi-carrier transmission system accurately, the method for estimating the available signal information noise ratio can be used for link self-adapting transmission solution of the generalized multi-carrier system based on Discrete Fourier Test spread-spectrum and radio material management.

一种DFT扩频的广义多载波系统的SINR估计方法，其通过首先建立所述离散傅立叶变换扩频的广义多载波传输系统的信号输入输出之间的数学关系，然后根据信道频率响应、信道噪声方差和均衡方法，设定所述DFT扩频的广义多载波传输系统的频域均衡子载波的均衡系数，再根据所述数学关系及所述频域均衡系数分别计算所述DFT扩频的广义多载波传输系统接收端有用信号的平均功率、信号间干扰的平均功率以及噪声方差，再计算有效信干噪比，如此以实现对广义多载波传输系统的有效信干噪比的准确计算，该有效信干噪比估计方法可用于基于离散傅立叶变换扩频的广义多载波传输系统的链路自适应传输方案和无线资源管理方面。

On the basis of analyzing the oscillatory frequency of crystal oscillator , the general expression of the frequency deviation of crystal frequency modulation oscillator is de rived .

本文在分析晶体调频振荡器振荡频率的基础上，得出了晶体调频振荡器频偏的一般表示式，最佳负载条件下的频偏设计公式和调制级有电流串联负反馈时的频偏设计关系式。

Results indicated there were significant seasonal and spatial distribution characteristics. Drought occurred in high frequency at the stage of tasselling to silking and thereafter. Drought frequency obviously increased with backwards shift of growth stage. Light drought happened in higher frequency than medium and severe drought.

结果表明，湖南春玉米生长季节内干旱呈现明显的季节性和空间区域分布特征：干旱频率较高的时段主要在玉米抽雄－吐丝阶段及其后的生育阶段，且随生育期后移干旱频率明显增加，以轻旱程度为主。

The results show that, under each drip irrigation treatment before the tasselling stage of spring maize, the fluctuation of average soil water content and soil matric potential at different soil depthes are comparative low under high frequency drip irrigation treatment, and the HDI can hold stable soil water content. The drip irrigation can obviously delay the effect of air temperature on the soil temperature, which was influenced by irrigation process, soil water content and crop growth stages. In addition, the irrigation frequency affects the spring maize root distribution in the soil, and the HDI improves the probability of root distribution in upper soil(0~40 cm). The yield difference of spring maize for irrigation frequency treatments is not significant under the typical field irrigation model combined irrigation with precipitation.

试验结果表明：在春玉米抽雄期以前阶段实施的滴灌各处理中，高频滴灌下土壤平均含水率和不同深度处的土壤基质势波动幅度较小，高频滴灌下土壤水分能保持在一个比较稳定的范围；土壤温度受灌水过程、土壤含水率及作物生育阶段的影响较明显，滴灌能显著延迟气温对土壤温度的影响；灌水频率对春玉米根系分布存在一定影响，高频灌溉能显著促进春玉米根系在上层土壤(0～40 cm)中的分布；此外，在这种典型的灌溉和降雨相结合灌溉模式下，不同灌水频率下玉米产量差异不显著。

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目前，本公司电磁振动给料机、气锤、料位计、电磁阀及控制仪、螺旋给料机、皮带输送机、斗式提升机、除尘器、零速开关、接近开关、高频线圈、电磁振动器、振动料斗、振动控制器、打标记电磁铁、电源调节器、加热单元、加热头、高频电缆、高频变压器、点火变压器等产品已销往全国各地，得到了用户一致好评。

I'm not an actor. I'm a professor of paleontology.

我不是演员，我是古生物学教授

Spider Network Web site that is a very image of the name.

网络蜘蛛即Web Spider，是一个非常形象的名字。