声学

Many methods exist for NDE ranging from acoustics to optical.

方法存在许多濒死体验到从声学光学。

In order to detect the nonlinear determinism, the method of surrogate is employed. The null hypothesis that a real system response is from a stationary Gaussian linear process distorted by an invertible, static, nonlinear measurement function is made and tested.

采用替代数据法对实际房间声学系统的非线性确定性进行检测，假设实际系统响应是由平稳高斯随机过程经可逆、静态的非线性函数变换而得到，然后对该假设进行检验。

This paper presents a quantificational evaluation to a specified high standard odeum via measuring on some main acoustic parameters.

通过对一个演出规格较高的音乐厅主要声学客观参数的测试，给出了该音乐厅定量的音质评价。

In order to know interval velocity in layered acoustic medium,re- locity analysis is made using wave field continuation and fuzzy decision theories.

为了获得层状声学介质的层速度参数，文中依据波场延拓理论和模糊决策理论改进了速度分析。

Based on this, a new WENO difference scheme which based on Dispersion-Relation-Preserving relation is developed, and representative test cases with this scheme for computational aeroacoustics problems has been implemented and compared in order to test capability of wave capturing; In addition, WENO schemes generally do not converge at high order in the presence of contact discontinuity of Euler equations, so a conservative front tracking technique coupling WENO schemes and Level Set method to simulate the translating density profile is presented here, and numerical simulation with this technique for representative test case has been implemented and results show the desired accuracy.

本文研究了高阶精度加权基本无振荡格式及其在双曲守恒律方程中的应用，在此基础上作了两个方面的工作：一是针对高频声波问题构造出一种基于保色散关系的WENO有限差分格式，并对计算气动声学问题的代表性算例进行了大量数值实验，比较了该格式捕捉波数的能力；另外，针对高阶WENO格式在处理Euler方程的接触间断时精度有所降低的问题，研究了利用界面追踪技术Level Set方法和高阶激波捕捉WENO格式相结合的一种守恒追踪方法，并且给出有代表性的密度滑移面问题的算例，得到一致高阶精度的数值模拟结果。

of A Dissertation on Chinese Traditinal Music Theory Chinese Dong Xiao Flute Music Culture: A Study Based on previous studies (particularly the findings and methods derived from archaeology, ethnology, the study of temperament, organology and acoustics), this dissertation endeavours to conduct a thorough and systematic investigation of the music culture surrounding the Chinese end-blown flute dongxiao.

中国洞箫音乐文化研究本文在以往学者研究成果的基础上，借鉴与本课题有关的考古学、民俗学、律学、乐器学、声学之成果与研究方法，对中国洞萧。。。

The results showed that the acoustic structures of non-passerine, sub-oscine passerine and oscine passerine\'s songs have significant differences.

结果表明，非鸣禽、亚鸣禽及鸣禽叫声的声学结构具有很大的差异性。

It gives up the unreasonable spherical hypothesis which is out of accord with the reality.

考察了不同壁面、空泡离壁面的距离和空泡的气体含量对空泡演化及辐射噪声的影响，该方法将边界元方法得到的空泡演化情况与声学方程在特殊情况下的解结合起来，放弃理论分析上不合理的球形假设，并考虑了边界的影响，这样更符合实际的空化现象，得到了与实验相一致的结论。

However, in practice, it is preferable that the acoustic drivers overlap in a top view.

但是，在实际中，优选的是在俯视图中声学驱动器重叠。

The worst type of room shape is a perfect cube - say, ten feet long, ten feet wide, and ten feet high - because all three dimensions are the same and all three dimensions resonate at the same frequency.

对于声学效果来说，最差的房间形状是完美的立方体——举例说就是长宽高都是10英尺，因为长宽高三个方向的距离都相等，所以三个方向上的共振频率都相同。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新