lower layer

基本解释

The data manipulation services (in the lower layer) extract data from the physical repositories, and semantic services turn this data into information.
数据操作服务（在下方的层中）从物理存储库中提取数据，并且语义服务将该数据转换为信息。
This means that routers strip off the Ethernet header upon reception of a packet, and then add a new lower layer header—Ethernet or otherwise—when the packet is forwarded.
这意味着路由器在收到数据封包时就会去除以太网的数据头信息，加上低一层的数据头信息（以太网层或者其他层的），然后发送给下一方。
While NLTK comes with a number of corpora that have been pre-processed (often manually) to various degrees, conceptually each layer relies on the processing in the adjacent lower layer.
尽管 NLTK 附带了很多已经预处理（通常是手工地）到不同程度的全集，但是概念上每一层都是依赖于相邻的更低层次的处理。

If I looked within the skin, one of the lower layers of your skin, the connective tissue layer, you'd find many fibroblasts there and they're just waiting in a more rounded shape than this, just waiting to do their job.
如果观察皮肤,更深处的一层细胞,结缔组织层,就能看到许多成纤维细胞,它们平时形状接近圆形,时刻准备着去完成自己的任务
耶鲁公开课 - 生物医学工程探索课程节选

But fewer ozone-eaters in the lower atmosphere mean that the ozone layer should eventually heal itself, perhaps by 2050 or so.
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To change your view layer in Apple Maps you have to tap the lower right corner (helpfully curled over as if it were physical paper) to reveal quite small traffic, satellite and hybrid views among four other options.
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The third layer uses TLC memory for capacity storage at a much lower price per bit.
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