查询词典 frequency response

This steady-state sinusoidal response is called the frequency response of the system.

这 个稳态正弦响应称为系统的频响应。

The advantages of linear, and distortion of small (uniform electric field than the magnetic field), good transient response, good high frequency response.

优点是线性好、失真小，瞬态响应好，高频响应好。

The array consisted of 8 piezoelectric crystal sensors, each coated with an adsorptive material with unselective, but different response characteristics. The frequency shift data obtained from the array as the response to mixed vapour of common organic solvents of small molecular size were treated by using stepwise discrimination analysis, and five coatings that provided the maximum level of analyte discriminating ability were selected. The array constructed from these solvents was applied to recognizing alcoholic hydroxyl, carbonyl from other organic functional groups. The principal component analysis was applied to the original and autoscalled data. The two-dimensional display of the data showed well-defined clusters for solvents containing different functional groups separated from each other. The array was applied to identifying spirits and beverages.

该阵列由八个压电晶体传感器组成，每个传感器涂以具有广谱响应性能的不同吸附活性材料，阵列对常见小分子有机溶剂混合蒸气的响应频移数据采用逐步判别分析处理，选出五个供信能力最佳的判别变量，以此构成的阵列用于小分子有机溶剂混合蒸气中醇羟基、羰基与其它官能团的识别，并采用主成分分析法降维投影，在二维空间含相同官能团的物质聚为一类；阵列可用于酒类、软饮料的识别。

The influence of structural damping coefficients on the peak value of the response of the vibration generator was investigated to determine the damping parameter according to the calculations of frequency response on the vibration generator.

通过对仿真模型进行频率响应计算，研究了阻尼对振动台响应峰值的影响情况，确定了各阻尼系数的取值。

The study of spatial configuration and characteristics of pulsed-wire velocity probe shows that: the yaw-and pitch-response characteristics have a good behavior due to the asymmetrical arrangement of the prongs. Because the amplitude of sensor wire response signal changes with the flow velocity, the differentiated signal is selected to trigger a voltage comparator. The pulsing frequency is restricted to about 100Hz to allow the wire to cool between pulses. The first velocity probe with big acceptance cone has been developed in China, and the way of measuring the Reynolds normal and shear stress and application have been given in this dissertation.

对脉冲热线空间速度探针的空间结构及特性的分析表明：三根长支架平行且安置于同一平面的探针结构可以获得大的测量角和好的测量性能；由于传感丝的响应信号幅值随流速变化较大，故应采用微分法进行信号处理；对于5μm的传感丝由于散热时间基本不变，约为10ms，故脉冲发射的最高频率为100Hz；本文在国内首次研制成功了一种大测量窗的脉冲热线空间速度探针，并给出了测量雷诺应力的方法和实例。

By time-varying filtering, we realize the signal selectivity and interference suppression, especially for the signals with time-varying power spectrum. It is shown herein that conventional eigenstructure based methods are lower dimensional special case of the time-frequency subspace fitting method. The closed-form array response estimation algorithms for blind source separation in wireless communication is also developed in the dissertation by exploiting the data structure of second-order statistics of the array output in the presence of multipath. The proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array utilized here can be of arbitrary geometry and even uncalibrated. Since the closed-form solution is obtained, no misconvergency may occur and large amount of computation can be saved. The equivalent feed model and corresponding optimization designation are proposed to realize the downlink multi-user selective transmission. By coherent and non-coherent superposition of the electromagnetical field, multiple beams can be formed using a single array, so that each co-channel user signal is transmitted in each beam and will not interfered with each other. The proposed system scheme implements the digital beamforming and the channel allocation in the base band, therefore is suitable for the utilization of the radio software technology. The feasibility and effectiveness of the proposed model are proved by the RF experiment.

在窄带条件下，GSC－SSF方法还可以提高阵列的虚拟孔径，从而提高估计的性能；可以证明，Cyclic DOA 和SC-SSF方法可看作该方法的特例或近似； 3、提出了二维GSC－SSF方法和宽带谱相关DOA矩阵方法，利用信号的循环平稳特性解决了宽带条件下二维 DOA 估计问题，并具有阵元数少、计算量较小的特点； 4、提出了时频子空间拟合和宽带时频DOA估计算法，将联合时频分析的理论和方法引入到阵列信号的空间谱估计研究中，利用时变滤波实现信号选择性测向和干扰抑制，特别适合于谱时变信号；可以证明传统特征结构法可看作是时频子空间拟合方法的特例； 5、提出了多用户环境下阵列响应的估计方法——CARE方法，该方法对信号结构和传播参数（主要是散射源分布与角度散布）的约束较少，适用于各种几何结构的阵列甚至未校准的阵列，能够直接得到阵列响应的闭式解，因此计算量小、稳健性好，不存在收敛问题； 6、提出了针对多用户下行选择性发送的阵列等效激励模型、优化设计方法及其系统实现方案，通过空间场的相干叠加与非相干叠加使得单一阵列能够形成多个波束，并保证各波束内的用户信号各不相同且相互干扰最小；其系统方案具有在基带实现数字波束成形、信道分配并便于软件无线电实现的特点，其有效性已得到外场实测数据的证实。

To realize high positioning precision and rapic response, this paper provides a variable parameter filter technique to filt positioning noise and high frequency noise meanwhile keeping rapid speed response, this technique has lower filter stiffness and damp paremeter in static state and bigger stiffness and damp paremeter in movement state using variable parameter technique, accordingly to solve the contradictions of positioning noise and positioning speed.

为实现系统高精度定位和快速响应，本文提出了采用宏定位变参数滤波技术滤除宏定位系统高频噪声，同时保持系统高响应速度。

It features the high sensitivity of a condenser microphone, yet exhibits the smoother frequency response and excellent transient response of a ribbon microphone.

R102铝带麦克风专为当今广播电视录音设计，它不仅具有电容麦克风的高灵敏度以及平滑的频率响应，又有比电容式麦克风更快的速度响应，速度响应为麦克风中的首选。

The numerical analysis results show that displacement response is periodic and synchronized with excited input current. The influence of linear magnetostriction coefficient, amplitude and frequency of excited current on the displacement response is investigated.

计算结果表明位移响应是周期的，并与电流变化同步还分析了材料的线性磁致伸缩系数及电流峰值和频率对输出位移的影响。

This paper makes use of PID control, Fuzzy- PID control based on single parameter these two control strategies to simulate the systems model. Compared with common vehicle, the results of simulation show that the vehicle equipped with the electromagnetic power steering system has better yaw velocity frequency response characteristic under condition with step input of steering wheel, so it has more betterhandling stability; Compared with PID control strategy, the results show that the Fuzzy-PID control strategy has the advantages, such as response fast, stabilize itself quickly and less over-altitude.

本文使用了PID、单参数自整定Fuzzy-PID两种控制策略对系统模型进行控制，仿真结果表明：相对于普通汽车，装有电磁式助力转向系统的汽车在方向盘转角阶跃输入的情况下，汽车横摆角速度频率响应特性更好，因此具有更好的操纵稳定性；而相对于采用PID控制，采用单参数自整定Fuzzy-PID控制又可以使系统响应更迅速、超调量更小、稳定更快。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。