查询词典 noise-power-ratio

ABSTRACT:The half-power bandwidth method is the commonly used method at home and abroad, the authors discover that factors, such as the sampling frequency, the frequency resolution, the ratio of the sampling frequency to the signal frequency, the analyzed width and the damping ratio, make the estimated damping ratio fluctuate vastly. Mostly the result is incredible except for some conditions, the error is sometime amazing, which is not acceptable.

半功率带宽法是国内外常用的测试阻尼的方法，笔者发现半功率带宽法由于受到信号处理中的①采样频率SF②频率分辨率△f③采样频率与信号频率之比K ④采样分析的长度T和⑤阻尼比D的大小等因素的影响使得测得的阻尼比值波动很大，除少数状态是可信的外，多数状态是不稳定的，有时误差惊人，得到的测试数据不能使用，易导致错误的结论。

The volume ratio of furaldehyde to acetic anhydride is 1∶2; the mole ratio of furaldehyde with anhydrous potassium carbonate is 1.00∶0.54. The best phase transfer catalyst is PEG1000, the mass ratio of PEG1000 with furaldehyde is 4.3%, the reaction time is 11 min, the reaction power of microwave is 260 W. The yield ofα-furanacrylicacid is up to 72.3% under these reaction conditions.

研究结果表明：在微波辐射功率为260 W、微波反应时间为11 min、以聚乙二醇1 000(PEG1000)为相转移催化剂，糠醛与乙酐的体积比为1∶2，糠醛与无水碳酸钾的量比为1.00∶0.55时，α-呋喃丙烯酸的产率为72.3%。

The comparison of the three noise values indicated that while the product of pulse width and angular frequency is larger than 1, the pulse width jitter would contribute considerable power to the total noise power spectrum, which is consistent well with the theoretical analysis.

比较三个噪声值表明了：在脉冲宽度角频率积Tω＞1的情况下，脉冲宽度抖动对总噪声量有较大贡献，脉冲宽度抖动不可忽略。

Then, both the stationary and non-stationary random response of hysteretic system with cubic rigidity and sticky damp were deduced and calculated. In the research of colored white noise, the filter for shaping the power spectral density was designed and the random state response of enlarged vector was gotten. With this, the experimental power spectral curve was changed into colored white noise and the random response could be easily calculated.

对平稳白噪声，给出了平稳响应的求解方法并对平稳状态下的模型参数对响应的影响进行了比较与分析；在有色白噪声的研究里，通过有色白噪声的扩阶方法和构造成型滤波器来计算有色白噪声的响应，从而解决一类工程实际振动问题的仿真模拟。

This burst waveform has benefits compared to a continuous wave emission in that the laser peak power can be very high for measuring long distances, yet the average power can be kept low for eye safety. And more, the pre-amplified optical receiver possessing temperature compensation and feedback resistance noise compensation is designed which is based on the noise spectrum density theory of silicon avalanche-photodiode.

同时根据硅雪崩光电二极管噪声谱密度理论，设计了具有温度补偿和反馈电阻噪声补偿的激光测距仪前放接收模块，详细分析了背景光，反向高压和反馈电阻对于Si-APD接收性能的影响。

Introduced the structure arrangent,refitting vehicle,decreasing noise and ventilation,heat emittion,etc of 90kW microbus for low-noise mobile electric power station and supplied some technical basis for this type electric power station s research and production in future.

介绍了90kW面包车型低噪声移动电站的结构布置、车辆改装、降噪及通风散热等，为今后该类型电站的研制和生产提供了一定的技术依据。

However, for the nonperiodic signal buried in high power noise, conventional method are usually not so effective as in the case with lower power noise.

然而，对于淹没于高功率噪声中的非振荡信号，传统的抑制噪声方法是无效的。

While increasing a woofer design's Xmax, at some point the woofer stops being a reproducer of music, and starts being a power tool of noise making. These "power tools" are more suitable for home theater where the typical sound being reproduced is noise anyway. But for music, forget it.

当增加低音喇叭的冲程时，它作为重现音乐一些特点被限制了，而开始变成制造噪音的强大工具，这对于家庭影院倒市是蛮适合的-那些声音中到处都是噪声，但是如果要听音乐-忘了它吧。

A methodology of noise-like key generation is presented. Chaotic process of tentmap function is used as a deterministic generation of noise-like key, image storage and retrieval are completed in a algebraic form. A mathematics model of noise-like chaotic coding memory is constructed, meanwhile the basic mechanism of circulant convolution and circulant correlation in image information storage and retrieval are demonstrated.

在详细阐明数字序列和字母序列的1-D映射函数设计方法的基础上，利用构造出的1-D映射的稳定周期环和不稳定极限环完成了存储和联想记忆功能，为了识别有关的输入信息，提出了映射函数直接控制的方法；在此基础上，提出了一种1-D映射型混沌神经网络模型，该网络本身不当作一个"黑箱"处理，网络的参数值由网络中实现的映射函数来确定，该网络模型具有联想记忆、容错性、模式识别和奇异滤波等一系列智能信息处理的基本功能。

In digitizing analogue signals, the digital signal is corrupted by the noise due to the inherent noise of the sampler and the quantizing noise.

在这两个过程中，由于采样器固有噪声和采样脉冲抖动噪声以及量化噪声等因素的影响，采用量化后的数字信号中含百噪声。

Liapunov—Schmidt method is one of the most important method in the bifurcation theory.

Liapunov—Schmidt方法是分叉理论的最重要方法之一。

Be courteous -- even when people are most discourteous to you .

要有礼貌──即使当別人对你最不礼貌的时候。