环境决定了开发，操作，策略和其他影响系统的设置和条件。[IEEE 1471]。
The environment, or context, determines the setting and circumstances of developmental, operational, political, and other influences upon that system. [IEEE 1471]
在这个定义中，你可以设置数据的类型和限制条件。
In this definition, you could set the types and the constraints on the data.
通过在数据计数器上设置过滤器和条件，很容易设置提醒。
It is easy to set up alerts by setting filters and qualifications on a data counter.
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