They allow a visual reference to the scenario.

它们允许这个场景有一个视觉参考。

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Combine images and text to create a visual reference board.

用图像和文字两相结合，创造一个可视化的提示板。

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Indicator light provides quick visual reference of a tripped condition.

指示灯能够快速跳闸条件的视觉参考。

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The Civil Aviation Authority said helicopters in London have only limited radar help and fly mostly using visual reference points on the ground.

CNN: London helicopter crash prompts safety questions

Comprised of a surface pattern of triangles-like those in the main theater, but made in this case out of 1, 067 thin aluminum panels, mounted on the support structure with open joints-the light-blue facade looks razor-sharp but creates the impression of a super-light floating skin dematerialized against the sky: another visual reference in the architecture to the infinite thinness of the moving image.

ENGADGET: Museum of The Moving Image plans multi-million dollar updates with HD, 3D

While not everyone has been able to get their hands on Blu-ray movies yet, many are reporting a surprisingly poor visual display from former DVD reference star The Fifth Element.

ENGADGET: Pre-release Blu-ray impressions roundup HD