two-way attenuation

Atmospheric attenuation of scene contrast is studied theoretically on the basis of radiometric principles, and the relationships between the measured maximal detection range for a target and visibility distance under two possible conditions are obtained.

根据辐射度学原理，从理论上研究景物对比度在大气传输中的衰减，得到了在两种可能的条件下所测得的目标最大探测距离与能见距离的关系。

互联网摘选

Evaluating the density of cancellous bone using quantitative ultrasound, it's a theory developed for more than ten years in the field of Ultrasonic Diagnosis Technic, broadband ultrasound attenuation ( BUA) and speed of sound ( SOS) are two pivotal parameters of the QUS diagnosis.

在超声诊断技术领域，定量超声骨密度检测理论已发展了十余年，宽带超声衰减（BUA）和超声声速（SOS）是用定量超声（QUS）进行骨质疏松症诊断的最重要的两项参数。

互联网摘选

The paper proposes and analyzes two turbo coded error control schemes to improve performance of optical wireless communication with long burst error by scintillation and attenuation.

在无线光通信系统中，光强闪烁和大气衰减等因素将使通信系统产生长突发误码，结合Turbo码，建议并分析了两种差错控制方案中时间参数的特性。

互联网摘选

The co-existence of Biot dissipation mechanism and thermal relaxation mechanism results in the appearance of two attenuation peaks in the attenuation curve of the saturated rock, i.e., the Biot peak and the thermal relaxation peak.

Biot耗散机制和热弛豫机制的共同存在使得饱和岩石的衰减曲线出现两个衰减峰，即Biot峰和热弛豫峰。

互联网摘选

Two sharp attenuation poles can be located close to either side of the desired pass-band to improve the frequency selectivity.

两个衰减极点分别产生在靠近通带的两边，提高了通带频率的选择性。

互联网摘选