条码是一种特殊的代码。条码是“一组规则排列的条、空及其对应字符组成的标记，用以表示一定的信息”。我国规定商品条码结构的国家标准是______。

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An Intranet is(71)the application of Internet technology within an internal or closed user group．Internets are company(72)and do not have a(73)connection to the Internet．Used properly an Internet is highly effective corporate tool，capable of regularly(74)information to empower the workforce with the information needed to perform. their roles．Used in this way，Internet represent a step towards the(75)office．

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在UML提供的图中，可以采用(30)对逻辑数据厍的建模；(31)用于接口、类和协作的行为建模，并强调对象行为的事件顺序；(32)用于系统的功能建模，并强调对象之间的控制流。

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