When the Nile is in flood, it deposits a layer of mud on the fields.

尼罗河泛滥时，在田野上沉积下一层泥。

《新英汉大辞典》

How this works: in the back end, Dapper will be analyzing the fields that publishers identify and will apply a layer of semantic classification on top of them.

它是这样运作的：在后端，Dapper会分析发布者定义的领域，并在上面应用语义分类层。

youdao

Storing session state in the client using HTTP cookies or hidden form fields has significant security risks — it exposes a part of your application internals to the untrusted client layer.

在客户端用HTTP cookie或者隐藏表单字段存储会话状态有很大的安全风险——它将应用程序的一部分内部内容暴露给了非受信任的客户层。

youdao

The wide-ranging storm buried parts of the Midwest under more than a foot of snow, weakening as it moved east but still carpeting lawns and fields in a fresh layer of white.

WSJ: Storm blasts East with snow, cold; warmer Tuesday