The packaging system behind Ubuntu can use packages officially supported and maintained by Canonical, and from third-party sources.

ubuntu背后的打包系统可以使用由Canonical官方支持和维护或者来自第三方的数据包。

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Zettabyte file system: Read more about the fantastic ZFS, originally created by Sun and now maintained by Oracle.

Zettabyte文件系统：进一步了解奇异的ZFS，它最初是由Sun创建的，现在由Oracle维护。

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The BISAC system is maintained by the book Industry Study Group, which classifies books into 52 broad categories, each with additional levels of specificity.

BISAC分类体系是由图书工业研究小组(Book Industry Study Group)维护的，它把图书分为52大类，每一类下面又有进一步的细分。

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Central to this is the city's badly maintained road system used by more than half-a-million vehicles, many of them old, polluting and unreliable.

BBC: Nepal film stars teach traffic police politeness

Green stormwater management is a collection of approaches that is dispersed across public and private land, and not a single system residing underground and maintained by one agency.

FORBES: Smart Communities will Build Green Infrastructure

Customers are better off if just one system is built and maintained, as long as the company that runs the system is prohibited by regulators from using its monopoly power to drive up prices.

NPR: Tea Party Targeting Southern Co. Power Monopoly