The horizontal separation between the limits of instrument (in clouds) flight airspace and those of the airways, air corridors and other airspace shall not be less than 10 kilometres.

仪表（云中）飞行空域的边界距离航路、空中走廊以及其他空域的边界，均不得小于10公里。

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Within our system of horizontal federalism and separation of powers at the federal (and, separately, the state) level, courts do not have the power to enforce their judgments in the trenches.

FORBES: When Technology Disrupts Enforcement of Judicial Decisions

It's this separation of layers and horizontal flow of current that gives OLET its efficiency and it's believed that it could not only be used for (next) next-generation displays but also for on-chip optical interconnects.

ENGADGET: Organic Light Emitting Transistors might make us forget all about OLED