standard sea level

The level of the ocean's surface, especially the level halfway between mean high and low tide, used as a standard in reckoning land elevation or sea depths.

海洋表面的水位，尤其是在平均高水位和低水位之间的平均位置的水位，用作计算陆地海拔和海水深度的标准。

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Kuang-Chi's helium balloon is 40 meters in diameter, and will float up to 100 kilometers above sea level, above the flight routes used by commercial airlines. It will relay WiFi signals to mobile phones and computers, circumventing standard, ground-based wireless services offered by telecom companies.

光启的氦气气球直径为40米，升空高度将超过客机的飞行高度，达到100千米。不同于电信公司向手机和电脑提供地面无线信号，信号将从气球中发射。

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The generally accepted standard is1020 watts per square meter at sea level.

普遍接受的标准1020在海平面每平方米瓦。

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