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 时间-频率 的翻译结果: 查询用时：0.031秒
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 时间-频率
 time-frequency
 By displaying the change of signal energy on a two dimensional time-frequency images based on time-frequency analysis, a new mathematical morphology method to distinguish target from the nonlinear time-frequency curve is presented. 利用时频分析方法将相干积累时间内由于目标非均匀运动和射频干扰引起的信号能量变化显示于时间-频率二维图像上,并根据目标信号对应时频图像上非线性曲线的特点提出一种基于二值形态学的方法用于区分目标和干扰信号。 短句来源 Time-frequency analysis can analyze nonstationary signal including earthquake signal. 时频分析能对非平稳信号进行分析,并给出地震波信号能量的时间-频率分布。 短句来源 Transient Signal Detection Technology Based on Bilinear Time-Frequency Distribution 基于双线性时间-频率分布的瞬时信号探测技术 短句来源 A novel approach to detect abnormal transient vibration signal for complex mechanical system is presented,where alias-free exponential bilinear time-frequency transformation is adopted to avoid the frequency alias and information loss in the traditional bilinear distributions. Simultancously,the cross-terms are effectively deduced with higher time-frequency resolution,which is validated by a gearbox early fault detection. 针对复杂机械系统异常振动信号的检测,提出一种新的无混叠指数双线性时间-频率变换探测方法,新变换方法可以避免常用双线性变换中的频率混叠和信息丢失等问题,能够有效的抑制交叉项,具有较高的时频分辨率,给出新的双线性时-频变换的离散算法,通过仿真实验与齿轮箱早期故障检测,对新的时频变换的检测效果进行了验证。 短句来源 Hilbert spectrum is direct time-frequency energy distribution. The points on time-frequency grids described meaningful and actual distribution. 得到的Hilbert谱图以直接的变量(时间-频率)来表达刻画信号本身能量的分布,使能量分布真正地以时间-频率网格点的形式出现,得到有意义的各个时间-频率-能量点。 短句来源 更多
 time and frequency
 The Mixed Time and Frequency Decimation FFT Algorithm (MDFFT) proposed by K. 本文对K. Nakayama提出的时间-频率混合抽选FFT算法作了简化和深化,提出了树形分解FFT算法,其实数乘法次数与K. 短句来源 The scattering function is one of most important mathematical method describing time-frequency dispersion channel performance, which embodies a concentrated reflection of the dispersion characteristics of the mobile radio channel in time and frequency domain, and reflects the angle dispersion distributed performance of the channel to a certain extent. 散射函数是描述时间-频率色散信道特性的最重要的数学方法之一,它集中反映了信道在时域和频域的色散特征,并还在一定程度上反映出角度色散的分布情况。 短句来源 Future broadband wireless communication systems should be able to provide reliable high-data-rate transmissions at low cost in time and frequency selective wireless channel. 未来无线通信系统应能在时间-频率选择性衰落信道中以低成本提供可靠的高速数据传输服务。 短句来源 Aimed at all kinds of methods of time-frequency analysis currently,this paper emphasizes on introducing the HHT method ,which deeply depicts the relationship between time and frequency and gets the time-frequency-energy figure of the analysed signal using the integration of EMD and Hilbert transform. 针对当前各种时频分析方法，本文重点介绍了Hilbert-Huang变换法(HHT，Hilbert-HuangTransform)，它利用 经验模态分解(EMD，Empirical ModeDecomposition)法与Hilbert变换的结合，深入地刻画频率与时间之间的关系，得到信号的时间-频率-能量图。 短句来源 Wavelet analysis is a new mathematical method and has acquired wide application in the field due to its fine character of making analysis according to multiple resolutions in time and frequency domains. 小波分析是一种新的数学方法,根据其时间-频率等多分辨率分析的优良特性,在许多方面获得广泛应用。 更多
 “时间-频率”译为未确定词的双语例句
 Hilbert spectrum has an energy-frequency-time distribution of the signal. Hilbert谱是信号的时间-频率-能量分布。 短句来源 Time frequency energy have been used for speech detection in noisy environments. 以前提出的基于时间 -频率的能量参数利用频域的限带能量加上时域能量来进行噪声中的语音检测。 短句来源 The characteristics of the urban heat island(UHI) intensity in Shanghai were studied and calculated using wavelet transformation, based on per hour difference in temperatures in 2000 observed from Davis automatic stations installed at the Urban and Suburb of Shanghai. 取上海市区各站点的平均温度与近郊站点的温度之差作为衡量城市热岛强度的指标,利用上海市城区和郊区的6个Davis自动气象观测仪每小时观测的记录,对2000年的温差序列进行小波变换,分析上海市城市热岛强度时间-频率的多时间尺度的演变规律. 短句来源 Doubly Selective Fading Channel Estimation Based on Polynomial Interpolation in MIMO Systems 基于多项式内插的MIMO时间-频率双选择性信道的信道估计 短句来源 Chirplet transform(CT) is extension of short-time Fourier transforms(STFTs) and wavelet transforms. 线调频小波变换统一了短时Fourier变换和小波变换的时频分析,是信号的时间-频率-尺度变换,能根据信号的特点自适应生成新的时频窗口。 短句来源 更多

我想查看译文中含有：的双语例句

 time-frequency
 We present two-sided singular value estimates for a class of convolution-product operators related to time-frequency localization. The Balian-Low theorem (BLT) is a key result in time-frequency analysis, originally stated by Balian and, independently, by Low, as: If a Gabor system $\{e^{2\pi imbt} \, g(t-na)\}_{m,n \in \mbox{\bf Z}}$ Gabor Time-Frequency Lattices and the Wexler-Raz Identity Gabor time-frequency lattices are sets of functions of the form $g_{m \alpha , n \beta} (t) =e^{-2 \pi i \alpha m t}g(t-n \beta)$ generated from a given function $g(t)$ by discrete translations in time and frequency. High-Order Orthonormal Scaling Functions and Wavelets Give Poor Time-Frequency Localization 更多
 time and frequency
 Gabor time-frequency lattices are sets of functions of the form $g_{m \alpha , n \beta} (t) =e^{-2 \pi i \alpha m t}g(t-n \beta)$ generated from a given function $g(t)$ by discrete translations in time and frequency. We present an explicit, straightforward construction of smooth integrable functions with prescribed gaps around the origin in both time and frequency domain. From the analysis of the electric field structure the conclusion is drawn that the bulk of the AKR power is carried by the signal component fast variable in time and frequency (flickering component). The spectrometer provides the programming of time and frequency parameters of pulse sequences and allows phase-sensitive detection of echo signals with their subsequent representation in digital form. Experimental data are presented on time and frequency dependences of the reverberation level for bistatic transmission and reception at low acoustic frequencies. 更多
 The equipment is aimed at manipulating five sectionalizing posts and provided with both, telecontrol and telesignaling. Time-frequency system is employed for the channel. Telesignaling from the five sectionalizing posts works continually and automatically in cyclic order. Self-checking duel information codes are adopted for each operation, in which the direct code is being compared with its inverse counterpart. The logic design is suitable for use, the circuitry is simple, and the equipment is reliable and easy... The equipment is aimed at manipulating five sectionalizing posts and provided with both, telecontrol and telesignaling. Time-frequency system is employed for the channel. Telesignaling from the five sectionalizing posts works continually and automatically in cyclic order. Self-checking duel information codes are adopted for each operation, in which the direct code is being compared with its inverse counterpart. The logic design is suitable for use, the circuitry is simple, and the equipment is reliable and easy in maintenance. 本文介绍了一套用于电气化铁道分区亭的电子装置。它是1对5的分散集中式系统,遥控与遥信综合于同一系统中。通道采用时间-频率划分。各被控站遥信为经常自动循环传送方式,信息码采用二次传送,正反码校核。逻辑设计合理,电路简单,工作可靠,维修方便。 126 lateral geniculate neurones were examined on unanaesthetized immobili-zed cats.The temporal frequency tuning curves of single neurones were measuredby stimulating the cat's eye with a sinusoidally modulated light spot,generated ona CRT and presented to each neurone's receptive field center or its surround.Theaverage discharging rate was used as an index to judge the sensitivity to different mo-dulating frequencies.By comparing the mean impulse rates responding to modula-ted light stimulations(modulated discharge... 126 lateral geniculate neurones were examined on unanaesthetized immobili-zed cats.The temporal frequency tuning curves of single neurones were measuredby stimulating the cat's eye with a sinusoidally modulated light spot,generated ona CRT and presented to each neurone's receptive field center or its surround.Theaverage discharging rate was used as an index to judge the sensitivity to different mo-dulating frequencies.By comparing the mean impulse rates responding to modula-ted light stimulations(modulated discharge rate)with those responding to unmodulatedlight(unmodulated discharge rate),two opposite effects were observed.The majorityof the cells(93.7)% showed modulation-excitatory curves in which the modulateddischarge rates were higher than the unmodulated ones.A minority of the cells(6.3%)showed modulation-inhibitory curves in which the modulated dischargerates were lower than the unmodulated ones.The modulation-excitatory curvescould further be grouped into two subtypes,the“band-pass filters”and the“low-pass filters”.Similarly,the modulation-inhibitory curves could also be dividedinto two subtypes,the“band-rejection filters”and the“low-rejection filters”.Onboth sides of the temporal frequency tuning curve subsidiary sidebands oppositein direction to the main part of the curves could often be seen,i.e.inhibitorysidebands flanking the modunation-excitatory tuning curve and excitatorysidebands flanking the modulation-inhibitory tuning curve.Most of the tuningcurves have only one peak.of the 110 curves measured the peak loci show anormal distribution which centered at 7 Hz.The tuning curves due to stimulationof different locations of the periphery were almost the same.But the tuningproperties of the receptive field centers were different from those of the periphe-ries either in shape or in band-width. 用示波器产生亮度受正弦波调制的小光点刺激清醒猫外膝体神经元的感受野,以不同调制频率下神经元放电的平均频率为指标,分析了126个细胞感受野中心的时间频率调谐特性,主要结果如下。(1)大多数(93.7%)细胞呈调制-兴奋型反应,即刺激光的时间调制在一定频率范围内使放电频率增加;少数(6.3%)细胞呈调制-抑制型反应,即在一定频率范围内,时间调制使放电减少。(2)根据调谐曲线的形状和通带宽度,调制-兴奋型反应包括带通滤波器和低通滤波器两种类型,其110个调谐曲线的峰值分布接近正态曲线,多数细胞对7Hz 的调谐最敏感。调制一抑制型反应包括带除滤波器和低除滤波器两类。(3)调制-兴奋型曲线的通带旁边较當出现抑制性侧带,调制-抑制型曲线出现兴奋性侧带。(4)感受野中心区与外周区的时间频率调谐曲线的带宽和形状有所不同。 This paper makes to model and predict the measured data in Variant Sample Time of Hydrogen, Cesium and Rubidium atomic clocks, mainly according to the principle of ARIMA models of time series analysis method with the Bias function theory of noise Variance of measuring statistics of atomic time/frequency and method of spline functions. Some preliminary useful predicting models and conclusions obtained in variant noise process have pretical sense in optimal predictions and monitoring of the behaviour of atomic... This paper makes to model and predict the measured data in Variant Sample Time of Hydrogen, Cesium and Rubidium atomic clocks, mainly according to the principle of ARIMA models of time series analysis method with the Bias function theory of noise Variance of measuring statistics of atomic time/frequency and method of spline functions. Some preliminary useful predicting models and conclusions obtained in variant noise process have pretical sense in optimal predictions and monitoring of the behaviour of atomic time/frequency and in developing new optimal filting control method to improve the performances of atomic clocks. 本文主要根据时间序列分析方法的ARIMA(autoregressive integraled moving averge)模型原理[1-6],结合原子时间频率测量统计学的噪声方差偏函数理论[7-9],以及适当采用样条函数方法[10],对氢,铯、铷等原子钟不同取样时间的测量数据进行建模和预报。对于不同噪声过程,初步得到了一些有用的预报模型和结论,这对于原子时间频率性能的最佳预报和监测(如跳相和跳频)以及研究新的最佳滤波控制方法以提高原子钟的性能指标都有实际意义。 << 更多相关文摘
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