查询词典 frequency

Based MUSIC method, a new approach for estimating instantaneous frequency of linearity frequency modulating signals and simulations are carried out. The results prove this approach has higher precision and better antinoise.

基于MUSIC方法原理，本文提出了一种估计线性调频信号瞬时频率的新方法，并进行了详细仿真，指出该方法具有较高的精度与较好的抗噪性。

The results show that injection locking synchronization is realized when injection rate is large enough. In the injection locking regime, similarity index is larger for external modulation than that for direct modulation. If injection rate keeps unchanged, synchronization is little affected by modulation index, but it is affected by modulation frequency. Since outputs of the master laser are antiphase for direct modulation and external modulation, the fluctuations of similarity index with modulation frequency for the two lasers are contrary.

研究结果表明：当注入强度足够大时，系统实现注入锁定同步，外部调制的相似指数大于内部调制；注入强度恒定时，同步品质几乎不受调制指数的影响，而受调制频率的影响；由于内部、外部调制引起主激光器的输出反相，两种调制方式下同步品质随调制频率的变化趋势也相反。

The receptance characteristics of track system has been predicted with the three dimensional track for high frequency vibration, with this model, the structure parameters of track system affect onreceptance have been discussed. The results show that the stiffness of ballast, sleeper mass, and stiffness of railpad are the main factors affecting on resonance and antiresonance under second resonance frequency.

利用轨道系统高频振动模型预测了各种参数对轨道系统导纳特性的影响，结果表明：道床刚度、轨枕质量和轨枕垫刚度是影响轨道系统第二阶共振频率以下共振和反共振的主要因素，随道床刚度增加，或轨枕质量减小，或轨枕垫刚度增加，第一、二阶共振和第一阶反共振频率增加，道床阻尼、轨枕垫阻尼主要影响第一、二阶共振和第一阶反共振振幅，阻尼越大，共振峰值和反共振谷值越平缓。

And children diet frequency, father educational background and age, mother age, family income all cause apparent difference on children diet frequency.

而幼儿饮食频率方面，父亲教育程度与年龄、母亲年龄、家庭收入皆对幼儿饮食频率有显著差异。

The results indicate that the thermal conductivity of Si3N4 thin film increases with the temperature;under high frequency stage the frequency has apparent effect on the thermal con...

测试结果表明：Si3N4薄膜的热导率随温度的升高而增大；高频段下，热导率受频率影响大，误差大；在低频段下薄膜热导率与频率变化基本无关；基于电子与声子的局部热平衡运输方程假设，S i3N4薄膜的热导率具有极度非平衡性；通过比较电阻、热导率与温度的关系可以看出加热器的尺寸大小会影响薄膜的热导率，最佳加热器的宽度选用20μm左右。

Because of the rapid development of the wireless communication technology, the design and research of the integrated circuits in the related field has gained more and more attention in recent years. And with the advance of the IC process technology, the cutoff frequency of MOS devices can reach several giga herz or more. It is a trend that CMOS process will replace the III-V compound process such as gallium arsenide or silicon bipolar process which were dominant in the fields of radio frequency and microwave.

近年来，由于无线通信技术的飞速发展，相关领域的集成电路的设计研究也受到越来越多的关注；同时由于工艺技术的不断进步，MOS器件的特征频率也可以达到几个GHz或更高的水平，原来在射频、微波领域占主导地位的三五族化合物半导体工艺如砷化镓及硅双极型工艺也有逐渐被CMOS工艺所取代的趋势。

X-Digital system company-- the Blackfin processor that ADI firm used in the compositive satellite receiver that a broadcast transmits systematic manufacturer to contain FM modulator in its. X-Digital system company uses Blackfin processor, offerred a kind of such products, promise satellitic operation business to convey digital frequency to still do not have the market that open far-- much resident is unit , for example hotel and apartment building. The satellitic receiver of X-Digital company changes digital satellite signal into the FM imitate signal that can be identified by receiver of consumptive assonance frequency.

X-Digital 系统公司--一家广播传输系统制造商在其带有FM调制器的集成卫星领受器中采用了ADI公司的Blackfin措置器。X-Digital系统公司采用Blackfin措置器，供给了如许一种产物，答应卫星运营商将数字音频传送到远远还没有翻开的市场--多住户单元，例如酒店和公寓大楼。X-Digital公司的卫星领受器将数字卫星信号转换成可被尺度的生产类音频领受器识此外FM模拟信号。

The results show that more modalities can be excited from asymmetric system and that there is little difference between the power flow spectra of rigid raft system and flexible raft system in middle and low bands of frequency, but there is considerable difference at high frequency.

研究结果表明，非对称系统能激励出更多的模态；在中低频段弹性浮筏系统和刚性浮筏系统的功率谱没有很大的区别，但是在高频段差别则很明显，浮筏的弹性模态起着主要作用；减小隔振器的刚度并适当增加隔振器阻尼不仅可以降低传递到基础的功率谱，同时还可以抑制共振减小冲击。

Though comparing Canny operator and center B spline dyadic wavelet, the following conclusion is proven in this dissertation: a Center B spline function has tight support and Canny operator hasn't. b Center B spline function asymptotic convergence to Gaussian function and the derivative of Center B spline function asymptotic convergence to Canny operator. c The derivative of fourth order center spline B function is more suitable as a optimal edge detector than Canny operator. d Center B spline function can balance the smoothing and approximation of original data, and the fourth center B spline function is the only optimal solution of two order smoothing problem. e The error between the valve of time-frequency uncertainty of the fourth center B spline function and the lower bound of time-frequency uncertainty does not exceed 0.143% of the lower bound. f The derivative of center spline B function can construct a stability dyadic wavelet and can give a fast algorithm for multiscale edge detection, but Canny operator can do neither.

作者给出了Canny算子与中心B样条二进小波严格的比较证明，得出如下结论：a中心B样条函数具有紧支集，Canny算子不具有紧支集。b中心B样条函数的极限收敛于高斯函数，中心B样条函数的导数收敛于Canny算子。c四阶中心B样条函数的导数比Canny算子更接近最佳边缘检测滤波器。d中心B样条函数比高斯函数更能兼顾对原函数平滑和逼近的折中要求，并且四阶中心B样条函数是二阶逼近问题的唯一最优解。e四阶中心B样条函数的时频测不准关系值与时频测不准关系下界的逼近误差不超过0.143％。f中心B样条函数的导数可以构成稳定的二进小波，存在快速的多尺度算法；而Canny算子不构成稳定的二进小波，无法给出快速的多尺度算法。

In this, and in the several other views, the line array loudspeaker may radiate over the full audible frequency range, or may radiate over a limited frequency range, typically the high audible frequencies.

在该视图和另外几个视图中，线性阵列扬声器可以辐射整个可听频率范围或可以辐射有限频率范围，通常为可听高频。

If you were not , and OS X just booted normally, have no fear.

如果你没有，和OS X刚刚启动通常，没有恐惧。

I only want to preserve our all .

我只想保存好我们的一切