Those produce a large number of faint reflections in what's called as: a smooth of echo.

这些（松针并不茂密的松树）能产生大量微弱的反射，我们称之为“平滑回声”。

youdao

Meterials and Methods: Reviewing the ultrasonic data of 76 cases with spleen mass proved by operation and pathology. The size, number, border, interior echo of the lesions were analysed.

材料和方法：回顾性分析76例脾脏肿块患者的超声检查资料，分析脾脏肿块的大小、数目、边界、内部回声等多种超声表现。

youdao

Automatic recognition of target number is realized through processing of target echo, and some practical results is given at end of this article.

通过对目标回波的处理，实现了目标架数的自动识别。最后给出了它们在实际应用中的结果。

youdao

Boston resident Sheryl Johnson had concerns which might echo why UKIP gained such a large number of votes.

BBC: UKIP: The view from Lincolnshire

The baby boomlet or baby boom echo group born between 1988 and 1995 have flooded colleges with demand for a limited number of spots.

FORBES: College Costs Out Of Control