查询词典 signal noise ratio

The results show that K-L transformation is an effective means to attenuate noise and improve signal noise ratio, and the effect of inhibition of the noise with K-L transformation is associated with the number of characteristic value.

结果表明，K-L变换可压制噪声提高信噪比，去噪的效果与所选取的特征值的个数有关。

To compare the image quality of the three sequences in two groups by One-Way ANOVA and T Test. The qualitative assessment standards include clarity, artifacts, signal uniformity, the conspicuity of enhanced vein and the observable grade of intrahepatic venous branchs. The quantitative assessment standards include SNR and CNR of intrahepatic portal vein and hepatic veins. Furthermore, the anatomy and variations of the intrahepatic portal vein and hepatic veins are statistical analysed.

通过方差分析和T检验分别对A、B组三个序列的图像质量进行比较，评定标准包括清晰度、伪影、信号均匀性、静脉强化程度及肝内静脉分支显示级数等定性指标和肝内门静脉、肝静脉的SNR(Signal-Noise Ratio，信噪比)及CNR(Contrast-Noise Ratio，对比度噪声比)等定量指标。

Meanwhile, the high master frequency band signal acquisition channel makes full use of the cymoscope sensitivity and hardware dynamic range, has larger analog signals front-located gain, thereby reinforcing the signal-noise ratio of the high master frequency band signal, and bringing along benefits for the later stage high resolutions seismic data process.

同时由于高主频频带信号采集电路充分利用了检波器的灵敏度和硬件动态范围，具有较大的模拟信号前置增益，使得高主频频带信号的信噪比得到增强，为后期高分辨率地震资料处理带来了较大益处。

Lecturing the technical requirements and constitution of light transmitter and receiver; the theory of noise of light receiver; analytic theories of signal/noise ratio and bit error rate for digital light receiver; technique of coding and decoding of line.

讲授光发送机和光接收机的组成及其技术要求；光接收机的噪声理论；数字光接收机的信噪比和误码率分析理论；线路编解码技术。

The results show that,all the three methods can effectively correct the frequency,the energy centrobaric correction has the lowest precision,and the ratio correction is the fastest and its precision is almost not affected by the change of signal-to-noise ratio.

标 签 信号处理激光多普勒测速仪离散频谱校正快速傅里叶变换 signal processing laser Doppler velocimeter discrete spectrum correction fast Fourier transform

The Raman scatter signal of carbon tetrachloromethane with this capillary/fiber optical was acquired, From this spectra, the scatter signal intensity and the signal/noise ratio were enhanced about 20 fold.

：本文提出了一种用于拉曼光谱研究的新型毛细管/双光纤传感器，对传感器构型和特性进行了研究，并将其用于四氯化碳样品的研究。

The design was optimized for maximum signal intensity by simulation and experiments. The size of focal spot in the micro-channel capillary was optimized. Fluorescence signal was enhanced 2～3 times when increasing the diameter of focal spot from 10μm to 50μm (full of the inner wall of capillary), through which the sensitivity and signal-noise ratio were also improved. A technique of using refractive matching liquid was presented. The fluorescence signals were boosted up and the signal collection efficiency was also meliorated when using this method.

通过理论分析和实验优化本系统的设计：优化聚焦于微通道中的激发光斑大小，增大聚焦到毛细管内径中的激发光斑尺寸，使光斑尺寸由最小的10μm增大到50μm，光电倍增管接收到的荧光信号提高了2-3倍，从而提高系统的信噪比和灵敏度；提出在聚焦物镜处加折射率匹配液的方法，加匹配液后的荧光信号得到了增强，因而提高了荧光收集效率和灵敏度。

After the cut-off frequency has been determined, the active noise-filtered system can be designed with several circuits to filter out those frequencies higher than the cut-off frequency and reserve the speech voice only. Besides, the music signals from the MP3 or a CD player can also be transmitted to the earplug system for increasing the signal noise ratio. The anxiety and tension of patients during treatments can, thus, be relaxed due to the euphonious music and toothaches of the patient might be further reduced.

本研究首先以离线的方式收集各类牙科噪音，然后将它传递到个人电脑，并使用CoolEdit及LabVIEW软体程式，分析出在牙科治疗过程中所产生之噪音的频率范围，最后透过各种比较，找出适当的截止频率，在截止频率(1KHz)被决定之后；针对该截止频率，使用主动式滤波的方式设计出相关的电路，组成主动式噪音率除系统，来滤除那些高於截止频率的噪音信号，只保留语音频率范围；此外透过mp3或cd player所播放出的音乐讯号，也可以同时被传递到耳塞系统来增加信号杂讯比，那麼当病人在治疗时，因为有这音乐可以使病人的焦虑跟紧张获得舒缓。

Methods 22 parients(35 ears)had been tested in three noises, including white noise,speech noiseand babble noise.BN was recorded when 8～12 persons were talking at same time.The monosyllabic phonetic balance word list was made by Shen Ye in 1983 and every list includs twenty-five words,Meantime ,the effect to speech discrimination score curve was tested in different signal to noise ratio.

目的 为了观察传导性聋患者在噪声竞争下言语清晰度曲线及不同噪声对清晰度曲线的不同影响；方法测试22名(35耳)传导性聋患者三种不同噪声竞争下测得的言语识别率结果，这三种噪声为①白噪声(white noise，WN)，②言语噪声(speech noise，SN)，③多人谈话声(babble noise，BN)，即由8～12人同时讲话录制而成，其频谱与言语长时平均频谱接近。

This thesis from the angle of signal detection, first theoretically gives out a RFOG closed signal detection design based on DSP. The signal detection system mainly includes related detection. signal conversion and the formation of feedback saw tooth. Related detection must guarantee signal synchronization sampling, and get the biggest signal noise ratio.

本文首先分析了谐振式光纤陀螺的基本原理和系统结构，并从信号检测的角度出发，从理论上给出了一个基于DSP实现的谐振式光纤陀螺的闭环信号检测方案，信号检测系统主要包括相关检测，信号的转换和反馈锯齿波的形成。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。