Actual background, necessity and significance of this study are explained.

说明本研究工作的实际背景、必要性和重要意义。

youdao

So the actual background error covariance is the key to success of data assimilation technique.

本文主要目的是建立具有实际运行能力的集合卡尔曼滤波资料同化系统。

youdao

In short, it's simpler and more accurate to use divs with actual text, and then drop in a background image for the div.

简而言之，使用带有实际文本的div会更加简单和准确，然后可以为div添加一个背景图像。

youdao

Please continue your reporting on the economy, but leave analysis on race to those with actual expertise and background in such matters.

ECONOMIST: On our endorsement of Barack Obama

When a player purchases a game, PS4 downloads just a fraction of the data so gamers can start playing immediately, and the rest is downloaded in the background during actual gameplay.

ENGADGET: Sony unveils its next game console, the PlayStation 4, arriving in holiday 2013

Although the Senate has rejected an attempt to block debate on expanded background checks for gun sales, leaders say debate over the actual bill could last weeks.

WSJ: Ten Things to Know Today