查询词典 threshold frequency

After transverse Zeeman effect is introduced to reduce the mode coupling, the laser could produce two orthogonal linear polarized components with 5MHz beat frequency. The effect of the magnetic field's direction to generation of the dualfrequency and the polarization property of the laser is investigated Based on theoretical study and experimental investigation to the beat frequency tuning character, a novel method for stabilizing the laser beat frequency is brought forward.

现代机械工业的发展使得机床、三坐标测量机等的运行速度已提高至1m/s，为适应这种发展趋势，本文研究了高频差（5MHz）激光干涉仪的光源、稳频和外差信号的处理等基本问题，建立了测量速度可达1m/s的高测速激光干涉仪，并对其在加工中心主轴热漂移测量系统和加工中心误差实时测量系统中的应用进行了研究。

We add a frequency compensation loop in an all digital CDR. This frequency compensation technique compensate large frequency variation in spread spectrum data.

在一全数位化的时脉与资料回复电路中，加上另一回路，以补偿在展频技术下产生的较大的频率变动。

The divide of the degree of auditory injury is basis on the dB decrease of equal number about pure tone of speaking frequency - testing threshold of audibility through air.

近年来，由于听觉脑干诱发电位不受被检者主观意识、睡眠、药物的影响，因此作为客观听力检测方法在法医学鉴定中已广泛应用。

Phenological observation data of plant communities from 1982 to 1996 at 5 sites and a method for phenological cumulative frequency modeling were used to determine the beginning dates of local phenological seasons and their corresponding threshold values of normalized difference vegetation index in each year.

利用1982～1996年5个站点的植物群落物候观测数据和物候累积频率拟合法，划分各站逐年的植被物候季节，并确定各季节初日对应的当地归一化差值植被指数阈值。

For the multifractal method, there is still no standard being set up to determine the threshold anomaly of metallogenic prognosis by the soil elements. This paper presents a calculation method using the cumulative frequency of elemental contentsnumber of deposits. The anomaly area obtained by this method can well identify the most of known deposits. Meanwhile, by this method some blank abnormal areas which are worthwhile to do further anomaly inspection have been identified.

多维分形方法下土壤元素成矿预测的异常下限值确定尚无标准，文中采用元素含量矿床数目累积频率的计算方法，基于该方法提取的成矿异常区域较好地识别出了绝大多数已知矿床，同时识别出了值得作进一步异常查证的空白异常区域。

The simulated results indicate that the properties of the chaotic dynamic system are sensitive to the driven frequency. A threshold value of amplitude exists for the appearance of chaos phase. The system is insensitive to the dissipative magnetic force.

数值模拟结果表明：混沌实验摆系统动力学性质灵敏地依赖于策动频率值；系统策动振幅必须大于一定阈值是混沌相出现的必要条件；磁阻尼参数对系统混沌相动力学状态影响不明显。

In this paper, a novel synchronization acquisition approach using the early-late gate for FFH/BFSK system is proposed, and it is based on frequency-PN sequence double pattern. Analytical and numerical results show the following advantages: the decision of threshold is more simple and accurate, and it overcomes the unreliableness of one-hop data demodulation, the unreliableness is caused by the not-alignment hop window of transmitter and receiver.

摘要针对FFH/BFSK系统的同步难题，该文提出了一种基于频率和PN序列双图案的早迟门同步捕获方法，理论分析和仿真结果显示，该方法门限的选择更为简单、准确；克服了全跳解调时由于收发窗口未同步引起的解调不可靠性。

A 40Hz event related potentialdetecting system is introduced here. The system employs the elliptic—type filters which have excellent edge features to extract signals of narrow band frequency . It exploits the correlation—threshold method proposed by us to cancel the musc1e artifacts.

详细介绍了我们建立的一套 40 Hz ERP(4 0 Hz事件相关电位)信号检测系统，该系统使用边缘特性最好的椭圆窄带滤波器提取窄带信号，采用我们提出的相关域值法很好地剔除了肌电干扰，并在微机上实现了实验自动化和结果自动统计。

Induced eddy currents circulate, and if of sufficient amplitude and duration, can cause neuronal depolarization. Compared with other stimulations, MS is non-contact, non-invasive and no pain. It is these advantages that make it gaine much popularity in clinic within the last decade. On the other hand, there are still some problems technically, such as bad focusing of MS coil, low frequency, the power is too large for reaching MS threshold in existence MS instrument.This paper presents general guidelines for designing and constructing a magnetic stimulator.

磁刺激具有非接触、非侵入、无痛等优点，近十几年来，在临床的诊断和治疗中得到广泛的应用，但现有的磁刺激仪存在如磁线圈聚焦性差、重复频率低、达到刺激阈值所需要的功率消耗过大等问题。

For reducing boundary distortion area, the elevations of grid DEM are viewed as a discrete sequence under a generalized coordinate, so that the boundary problem of two-dimensional discrete wavelet transform is turned into the boundary problem of one-dimensional discrete wavelet transform, which not only greatly reduces the boundary distortion area, improves the precision of reconstructed DEM data near the boundary, but also decreases the number of zeros adding on the boundary for wavelet transform, and boosts the compression ratio. On the basis of analyzing the distribution characteristics of coefficients in low and high frequency bands, a mixed entropy coding plan is applied, and a high efficient quantizator called"self-adaptive hard threshold"is established, which is helpful for improving the precision of the reconstructed DEM data and for enhancing compression ratio.

为了减小小波变换山区格网DEM数据压缩中边界失真区域，将山区格网DEM高程值视为广义坐标下的离散随机序列，把二维离散小波变换中的边界问题转换为一维离散小波变换中的边界问题，不仅大大减少了小波变换边界失真区域，提高了重构DEM数据边界点的精度，而且减少了边界补零个数，提高了压缩比；通过对山区格网DEM数据小波变换低频区和高频区变换系数分布特点的分析，采取了霍夫曼—游程混合熵编码方案，设计了高效、低失真的"自适应硬阈值"量化器，即对低频区变换系数不进行量化，直接进行霍夫曼编码；对高频区变换系数则先用"自适应硬阈值"方法量化处理，再进行游程编码。

Who? I never heard of him, Paul said, before asking teammate James Posey if he had heard of him.

赛后，科比说，他一直都是一名非常出色的射手，今天他打得很棒。

When I joined the company, I rotated around the different sections.

我加入这个公司时，轮换过几个不同的部门。