频率

The paper studies UFLS with severaltimes accelerating shedding load function, analyzes dynamic frequencycharacteristic of power system during UFLS, derivesthe formula which is served as setting rate of frequency change for criterionof accelerating shedding load, and designs the logical diagram expressing UFLSoperation.

研究了同时依据频率和频率变化率两个变量，在每个频率定值处设置加速减载功能的低频减载方案。文中详细分析了低频减载过程中频率的动态特性，推导了作为加速减载判据的频率变化率整定值的计算公式。

In series capacitance,the low frequency is load resonance frequency.In parallel capacitance,the high frequency is load resonance frequency.

在串联电容时，负载谐振频率是两个频率中的较低的那个频率，而在并联电容时，负载谐振频率则是其中较高的那个频率。

In this chapter, three kinds of target recognition methods are performed, which are:①Target recognition method based on the description of polarization parameter plane. The echo polarization states of target are projected onto the polarization state plane described by the ellipticity ε and the tilt angle τ of the polarization ellipse, the change of parameter following ferquency becomes the chart. According to the changing trait of the chart, the multidimensional polarization feature space of target has been contructed. Furthermore, a series of polarization feature parameters used in designing the structure of target recognition device are extracted, and they are insensible to the posture of target.②Target recognition method based on the description of Poincare polarization sphere. The echo polarization states of target expressed by Stokes vector are projected onto the Poincare polarization sphere. The conception of polarization ferquency stability, which is used in describing the dynamic distribution characteristics of the target echo polarization states on Poincare polarization sphere, has been defined. A group of polarization feature parameters used in designing the structure of target recognition device are extracted, and they are insensible to the posture of target.③Target recognition method based on the description of frequency sensitivity. In accordance with the conception of the polarization state distance defined on Poincare polarization sphere, the frequency sensibility of the physical structure property of target has been investigated, the frequency distribution feature curves in PSD domain are obtained, and targets'features are extracted by means of the curve-fitting method with Least Square Criterion.

这章具体研究了基于三种极化散射特性描述的相应的目标识别方法：①基于极化参数平面描述的目标识别方法，将目标回波极化状态投影到以极化椭圆参数，即椭圆率角ε和倾角τ表征的极化状态平面上，参数随观测频率的变化就形成了图，根据图的变化特点构造了目标的多维极化特征空间，并提取了不敏感目标姿态变化的极化特征参数组来设计目标的识别器结构；②基于Poincare极化球面描述的目标识别方法，采用Stokes矢量表征目标回波的极化状态，并将其投影到描述极化状态的Poincare极化球面上，定义了极化频率稳定度的概念用以刻画目标回波极化状态在Poincare极化球面上的动态分布信息，提取了准方位不变性的目标极化特征，最后设计了目标的识别器结构；③基于频率敏感性描述的目标识别方法，通过在Poincare极化球面上所定义的极化状态距离的概念，研究的是复杂目标物理结构特性对探测信号频率的敏感程度问题，获得了在极化状态距离下的频率分布特性曲线，采用最小二乘估计曲线拟合方法，它既用于极化特征的降维，同时又直接将拟合参数作为目标的分类特征。

The minimum fluidization velocity has a minimum value when the frequency of sound waves is 120Hz and it will decrease as the sound pressure level increases. The degree of sound attenuation will increase while bed material is higher and the fluidization quality of fine particles will become poor and the minimum fluidization velocity will increase. Compared with TiO2, the SiO2 fine particles have a better quality of fluidization at the same fluidized conditions.The cluster/subcluster model and oscillators model are used to describe the fluidization characteristics of fine particles in a sound-assisted fluidized bed. The theoretical calculations show that the minimum fluidization velocity umf is decreased with the SPL increased at the same frequency of sound and the quality of fluidization is better.

论文还系统的考察了声压和频率对纳米SiO2和TiO2颗粒流化特性的影响，结果表明：在频率一定的情况下，声压越高，流化床中形成的聚团尺寸越小，最小流化速度越低，流化质量越好；当声压低于120dB时，声场对超细颗粒流化特性的影响减小，当声压大于130dB时，则能显著改善流化效果，使流化床内的颗粒聚团明显减小，最小流化速度明显降低，粉体带出减小；声压一定，频率为120Hz左右时，最小流化速度最低，此时流化床中形成的聚团尺寸最小，流化效果最好；超细颗粒达到较好的流化状态存在一个最佳频率范围，随着声压增高，这个频率范围将增大。

Result: Contrary to European and American people, I allele frequency of Han nationality is higher than that of D allele (P.05); II genotype frequency and DD genotype frequency are noticeably different from that of European and American people (P.01); No DD genotype appear in the excellent athletes, which is noticeably lower than that of control group and athlete group (P.05) and that of the excellent athletes reported in other countries; the frequency distribution of II genotype in Marathon is noticeably higher than that in 5km distance running(P.10); The changing of I allele Jl genotype IP ID genotype frequency indicates a stronger unary liner relation (r=0.9985) with the running distance lengthening(5ktru lOkrru Marathon).

结果显示：与欧美人群相反，汉族I等位基因频率高于D等位基因（P＜0.05）；汉族II型纯合子频率和DD型纯合子频率非常显著地区别于欧美人群（P＜0.01）；在优秀运动员中，DD型纯合子未出现一例，显著低于对照组和运动员（P＜0.05），也显著低于国外已报道的优秀运动员；马拉松项目II型频率分布显著高于5km（P＜0.10）；I等位基因、II基因型和ID基因型的频率变化伴随专项距离（5km、10km、马拉松）的增加呈现强相关的一元线性关系（r=0.9985）。

The method includes acquiring with the frequency meter the tested clock signal and measuring its frequency; sending the tested frequency value to the data acquisition and processing module for calculation and processing regularly; and processing the frequency data comprehensively in the data processing output module and displaying output figure and historical data.

所述的方法包括：首先，频率计采集待测时钟信号，并测试其频率值；然后，频率计定时将测试得到的待测时钟信号的频率值发送给数据采集处理模块进行计算处理；最后，数据输出处理模块对接收数据采集处理模块处理后的频率数据进行综合处理，并将获取的图形数据和历史数据显示输出。

Methods Basolateral amygdala slices of rats were prepared. Field excitatory post-synaptic potentials of BLA were recorded by stimulating the external capsule. Two TBS's were applied to induce LTP in BLA. Each TBS included a brief, high-frequency pulse train (5 pulses at 100 Hz) given at the theta-rhythm (5Hz) for 4 seconds. Experiments compare the effects of different intervals of two TBS's on the expression of LTP in BLA.

制备杏仁核脑片，刺激外囊记录BLA场电位，应用两串θ频率波刺激诱导LTP，每串θ频率波刺激为20个(频率5Hz)短时间高频串脉冲(5个脉冲，频率为100Hz)，通过改变两串θ频率波的刺激间隔，分析不同参数诱导的LTP是否存在差异，并在灌流的人工脑脊液中加入TPK抑制剂genistein，观察其对杏仁核LTP的影响。

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。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。