Objective To quantify the acoustic density of atherosclerosis plaques with different echogenicity in carotid artery.
目的对人体颈动脉内不同回声强度的粥样硬化斑块进行声学密度定量。
With the concentration of the polymer solution increasing, acoustic velocity of the polymer solution decreases, and the polymer density decreases too, but the apparent viscosity increases.
随着聚合物溶液浓度的增加，其声传播速度减小，其密度值也逐渐减小，但其表观粘度值逐渐增大。
It is necessary to record the linear scale before and after log and the time difference curve in the acoustic variable density log.
摘要阐述了声波变密度测井时对其进行测前、测后线性刻度及记录时差曲线的必要性。
In acoustics, the product of velocity times density, also called acoustic impedance and symbolized by z.
声学中，速度与密度的乘积就是阻抗，也称为声阻抗或波阻抗，用符号Z表示。
It is necessary to record the linear scale before and after log and the time difference curve in the acoustic variable density log.
阐述了声波变密度测井时对其进行测前、测后线性刻度及记录时差曲线的必要性。
The status for acoustic variable density log in Daqing Oilfield is introduced including applied techniques and logging tool levels.
介绍了大庆油田声波变密度测井的现状、应用的技术和仪器的水平。
Methods The color and transparency of different concentration phantoms were observed. Properties including density, acoustic speed and acoustic attenuation of PAA gel phantom were measured.
方法观察模块浓度的不同所致颜色与透明度的变化，并对PAA模块的声学特性包括密度、声速及声衰减进行测量。
The results show that acoustic response feature of random vibration depends on the acoustic response function and the spectral density function of the stimulating load.
理论推导和实例结果表明，随机振动的声学响应特性取决于声学频率响应函数和激励谱密度函数。
The rock acoustic parameters in this paper include wave amplitude, spectral amplitude, spectral area, spectral density, wave velocity and attenuation coefficient etc.
这些岩石声学参数为波幅、谱幅、谱面积、谱密度、波速度、衰减系数等。
Mode conversion efficiency has been calculated as functions of acoustic frequency, interaction length, guiding layer thickness, and acoustic drive power density.
模式转换效率可化作声波频率、声光作用长度、波导厚度和声波功率密度的函数，并利用数值计算得出结果。
Acoustic velocities of tap water and polymer solution were studied using ultrasonic-pulse reflection method in the laboratory. Polymer density and apparent viscosity were measured.
采用脉冲反射法在实验室条件下对自来水和不同浓度聚合物溶液的声速进行了测量研究，经测量得到了聚合物溶液的密度、表观粘度。
Acoustic logging and density logging are the ripe and conventional techniques for gas finding.
声波、密度测井是成熟的常规找气方法技术。
It is suggested that the instability is excited in the low density plasma when the electron beam drift velocities exceed the ion acoustic speed.
不稳定性产生的可能机制是由于电子束穿过低密度本底等离子体的漂移速度超过离子声速而激发起来的。
FEM model for calculating energy density and acoustic energy is built based on work above.
划分。5在前面工作的基础上，建立了声能密度及声能的有限元计算模型。
Based on the suitable channel model, an implementation of quasi-cyclic low density parity check codes (QC-LDPC) for acoustic communication system in shallow water is demonstrated.
讨论了准循环低密度校验码(QC - LDPC)在浅海水声信道中的实现方案。
It is shown that the flow instability with high frequency belongs to acoustic oscillation and the flow instability with low frequency is density wave instability.
高频脉动属于声波型脉动，低频脉动属于密度波型脉动。
According to structural feature of typical geologic models in Shengli oilfield, the paper presented staggering mesh high-order difference forward simulation of density-variated acoustic equation.
根据胜利油田典型地质模型的构造特点，本文提出了变密度声波方程交错网格高阶差分正演方法。
Furthermore, the energy density spectrum for electromagnetic wave, Langmuir wave and ion acoustic wave are obtained and used to interpret spectra evolution with time.
研究了电磁波、朗缪尔波与离声波在相互作用中的能量密度谱随时间的演化；
In the course of acoustic-gravity wave (AGW) propagation, a coupling relation between the ozone density oscillations (ODO) and temperature fluctuations (TF) in the lower thermosphere is presented.
本文求出了声重波传播过程中，低热层臭氧含量振荡和温度场起伏间的耦合关系。
This paper also studied the influence of acoustic power density, temperature and other parameters on the ultrasonic cleaning through experiment.
通过比对实验分析了驻波和清洗介质的性质对清洗效果的影响。
This paper also studied the influence of acoustic power density, temperature and other parameters on the ultrasonic cleaning through experiment.
通过比对实验分析了驻波和清洗介质的性质对清洗效果的影响。
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