The main layers of the application are a database, a persistence framework, a database access object, and user interface (UI) controller and view layers.

应用程序的主要层是数据库、持久性框架、数据库访问对象和用户界面(UI)控制器及视图层。

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A UNIX operating system has many layers, and the layers that the tools examining its object files expose are close to the hardware.

UNIX操作系统具有许多层次，那些通过工具查看目标文件所公开的层次，非常接近底层硬件。

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On the other hand, the object domain model also has its limit, particularly in SOA environments, where flexibility and solutions spanning multiple layers and systems are of Paramount importance.

另一方面，对象领域模型还有自己的局限，特别在SOA环境中更是如此；在SOA环境中，跨越多个层次和系统的灵活性和解决方案是最为重要的。

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Printing in 3D involves sending a design file to a printer that then forms a solid version of that object by slowly building it up in layers of plastic.

BBC: Nokia backs 3D printing for mobile phone cases

There are obviously some very able and very serious people in the business, but they are forced to use the procedures appropriate to this kind of market in which the ultimate object, better health, is concealed under a dozen layers of advertising, chicanery and what-not.

FORBES: How To Solve The Health Care Crisis