和声学

Acoustics - Reference zero for the calibration of audiometric equipment - Part 1 : reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones .

声学。测听设备校准用参照区。第1部分：纯音和耳挂式耳机的参考等效阈声压级

High-Resolution Bathymetric SideScan Sonar is a kind of acoustic equipment which can be applied on the high-resolution seabed terrain and physiognomy surveying.

中文摘要高分辨率测深侧扫声纳是一种能够探测高分辨率海底地形和地貌的声学设备。

Due to their special network structures and larger specific surface area, the carbonized aerogel is widely used in the field of mechanics, acoustics, electricity, calorifics and optics.

由于其独特的网络结构和高比表面积，使得碳气凝胶在力学、声学、电学、热学以及光学等领域都有潜在的应用价值。

After esterification by BTCA Acoustic properties of picea sitchensis Carr.andChamaecyparis Iawsoniana ParI were changed,(treated/untreated ratio):Loss tangentdecreased 10～2424% in the tangential ofpicea sitchensis Carr,9～17% and 10～22% in thetangential and radial directions of Chamaecyparis Iawsoniana ParI.,respectively.Specificdynamic Young's modulesand acoustic radiation coefficient of two wood changedunremarkably,in the tangential direction with increment of ASE.Specific dynamic Young'smodulesincreased 3～9% in the radial direction.tgδ/E of decreased 9～27% intangential of picea sitchensis Carr,7～14% and 10～26% in the tangential and radial directions ofChamaecyparis Iawsoniana ParI.,respectively.

BTCA酯化处理西特克云杉和美国扁柏木材的声学性能发生了变化，处理材与未处理材比值，损耗角正切tgδ：西特克云杉纵向下降10～24％，美国扁柏下降纵向9～17％，径向10～22％；比动态弹性模量E/ρ：两种树种的纵向变化均不明显，随着ASE上升变化不规则，美国扁柏径向上升3～9％；声辐射阻尼的变化类似于比动态弹性模量E/ρ的变化；tgδ/E：西特克云杉纵向下降9～27％，美国扁柏下降纵向7～14％，径向10～26％。

Because of the existence of natural detecting blind area o f general radar on detecting flying object flying in veryˉ low altitude, it is so essential to put forward a suspended bomb t heory which would make use of sound wave's characˉ teristic parameters as its wavelength and spectrum to get the obje ct's direction and position, and to discuss its orientaˉ tion method and embattle model.

由于现有的常规雷达探测超低空飞行的来袭兵器有其固有的盲区，作为雷达的必要补充，利用声音的大小、频谱等特征能够反映声源的方位等特征参数的特性，提出了一种被动声学探测悬浮弹理论，并对其定位算法和布阵模式进行探讨，目的是防御拦截低空超声速巡航导弹。

Therefor, the limits to explain isolatedly the individual process of light emission in microlaser only through cavity quantum electrodynamics effect can be avoided by the connecting the cavity quantum acoustics effect and the cavity quantum electrodynamics effect and dealing with the emission problems in microlaser from the overall point of view.

因此将&腔量子电动力学效应&和&腔量子声学效应&结合起来，从全局的观点处理微激光器中的发光问题，避免了单用&腔量子电动力学效应&孤立地解释微激光器中发光分过程所导致的局限性。

Objective To evaluate the effect of multimodality MR imaging and myocardial contrast echocardiography in determination of myocardial perfusion and decision of myocardial viability.

目的评价MR多技术扫描和心肌声学造影在检测心肌灌注、判断心肌存活中的作用。

Yann Tambour has previously made music as the founder and orchestrator of Encre, a project which made use of samples, guitars electric and acoustic as well as other live instruments and his own unmistakable voice.

在21世纪初通过一次个人命名专辑的机会，他的实力在法国音乐风景中显现出来，专辑主题是&墨&计划-一个非凡，独特且不妥协的天地；忧郁但经常情感细腻；样品编辑器；电声乐器；吉他；声学和电的；还有低声细语般演唱的交锋与会面。

An adaptive conjugate gradient algorithm based on subband decompsition structure was proposed for acoustic echo cancellation in communication systems.

针对通信系统中的声学回声干扰问题，研究了一种快速收敛和有效的自适应回声抵消算法。

The advent of the acoustic Doppler current profiler made possible the development of a discharge-measurement system capable of more accurately measuring unsteady or tidally affected flow.

随着ADCP(Acoustic Doppler Current Profilers)声学多普勒流速剖面仪的出现，使得更准确的测量不稳定流和受潮汐影响的流量测验系统成为可能。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。