bottom layer

基本解释

If you had to build one subsystem at a time, such an architecture would force you to build the bottom layer subsystems first, and then go higher and higher up.
如果你必须要在一个时间内构建一个子系统，这样的体系架构将迫使你首先构建底层的子系统，然后构建越来越上层的子系统。
Straw, chaff, animal hair, and quartz were part of the mixture that protected and strengthened the clay material, as did ropes attached to wooden pegs at the bottom layer.
为了保护和强化陶泥，混合物中添加了稻草、谷壳、动物毛发和石英，底层还用绳子与木桩相连。
It is best to think of the top layer as the component broker layer, as the flow logic in this layer is brokering the components in the bottom layer to deliver overall application functionality.
最好是把上层看作组件代理层，因为这一层中的流逻辑负责代理底层中的组件以提供整个应用程序的功能。

The bottom layer has hundreds or thousands of tiny intersecting liquid-handling channels, each about the width of a human hair (100 microns).
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