查询词典 difference frequency

The Complex Frequency Image Method which estimates the positions of poles by the positions of maximums of the negative second order derivative in complex plane is presented, and on its basis the Complex Frequency Trap Method is given.

提出了由复平面上负二阶导数的极大值的位置来估计极点位置的复频图象法，并在它的基础上给出了复频陷波法。

The preliminary chromatogram data were resolved with Mallat algorithm of wavelet analysis theory. This method that resetting the high frequency signals, reconstructing low frequency and then correcting the background signals in the original signal was to avoid the data skewness with negative digital points after background correction and achieve the baseline correction; according to the study and analysis of simulated data including curve background and real data of the needle-plate and free metal partials insulation defects, the method is effective; the best wavelet function of the background correction is Db5 and the best resolution times of the background correction is 8 for chromatogram data of SF_6 decomposition products, based on the calculation with different wavelet functions and resolution times.

在初步获取的气相色谱数据基础上，运用小波分析技术中的Mallat算法对色谱数据进行小波分解，采取将高频信号置零，重构低频背景信号，再用原始信号扣除背景信号的方法，并对背景信号进行纵向平移以避免扣除后出现负数据点造成色谱峰失真的题目及达到色谱图基线校正的目的；通过对含曲线背景信号的模拟色谱数据和针-板、自由金属微粒缺陷下的真实数据的计算研究表明，该方法的应用是有效的；并通过对不用小波函数和不同分解次数的背景扣除计算，确定了SF_6气体放电分解组分色谱背景扣除所选用的最佳小波函数为Db5小波和最佳分解次数为8次。

After analyzed RFID and NFC technology, they are considered as radio frequency communication and listed up some examples of other radio frequency.

本文在分析射频识别和近场通信的基础上，指出它们同属射频通信，而且列举了射频通信的其他技术。

Berause of the fact that when image resolution is reduced, the image high-frequency characteristics are distorted and the image low-frequency characteristics are held, this method has noiseproof feature and large-scale weak edge detection property.

由于低分辨率采样下图像高频特征失真较大，而低频特征失真较小的原因，这一算法能很好地抑制图像噪声，有效地提取出图像中大尺度弱边缘。

Objective To assess the value of high frequency ultrasound in early finding and diagnosing carciˉnoma of thyroid in health screening.Methods To apply high frequency Ultrasound generally to examine thyroid in health screening.To register age and sex and sonography point of tumor of doubtful carcinoma of thyroid case.To apˉply more CDFI technique to construe its blood stream character.To based record of health.To based responses system for certain case and to callback.

目的 探讨高频超声在健康体检中对甲状腺癌的早期发现及诊断价值方法在健康体检中，应用彩超的高频线阵探头常规检查甲状腺，记录可疑甲状腺癌病例的年龄、性别，肿块的声像图特点，进步应用CDFI技术分析其血流特征，建立健康档案，对经手术病理证实的病例建立随访制度，定期复查。

Results The frequency of CD70+CD4+ lymphocytes was 14.55%± 5.49% in normal control group, 85.25%± 14.08% in active SLE group, 77.65%± 18.77% in nonactive SLE group, and 81.54%± 8.71% in methylation-inhibited group. Compared with the normal control group, a significant increase was observed in both the frequency of CD70+CD4+ lymphocytes （all P 0.01） and the expression of CD70 expression （all P 0.05） in other three groups.

结果 正常人外周血CD4+CD70+ T淋巴细胞阳性率为14.55%± 5.49%，活动期、非活动期SLE分别为85.25%± 14.08%和77.65%± 18.77%，甲基化抑制组为81.54%± 8.71%，与正常人对照组相比，活动期、非活动期SLE患者和甲基化抑制组CD70+CD4+ T淋巴细胞阳性率均明显升高（P 0.01），其外周血T淋巴细胞CD70 mRNA表达水平亦明显增加（P 0.05）；SLE患者外周血CD70+CD4+ T淋巴细胞阳性率与SLE疾病活动度呈显著正相关（r = 0.72，P 0.05）。

The frequency of this synthesizer can be changed from 405700.0000Hz to 405799.9999Hz with a minimum step frequency of 1 ×10-4Hz. The measured results show that nonharmonic interrelated spurious output of the synthesizer is less than -85dB.

该综合器的非谐波相关的寄生输出小于-85dB，频率的短期稳定度是2.07×10~(-11)/0.1s、2.48×10~(-12)/1s、2.88×10~(-13)/10s；当温度由20℃变至40℃时，综合器相位漂移Δφ=28.8°；当电源电压为+16V～+19V或+5V～+6V时，综合器输出相位不变。

The multiple nonlinear trend of autocorrelation function is presented for similarity search of high frequency financial data, and experiments about trend prediction of high frequency financial data have been done.

提取多元时间序列的自相关函数的多重非线性特征，以此来建立金融高频数据的相似性查找方法，并就金融高频数据的趋势预测展开具体的应用研究。

Chapter 5 indicates that multi-scale time-frequency analysis such as wavelet and EMD could offer more information of HRV than traditional linear analysis ways in time domain and frequency domain, which is a research trend with those nonlinear ways.

第五章将从研究方法上指出以小波分析和EMD为代表的多尺度时频分析可以比通常的HRV时频分析方法揭示更多的信息，和非线性动力学分析一起成为HRV分析的发展方向。

Considering the low effective of GARCH model for high frequency data,the nonparametric method is adopted to estimate the value at risk of high frequency data.

文章在GARCH模型对高频数据低效的情况下，从非参数的角度给出风险价值一个相合估计量，这个估计量不依赖于总体分布。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。