For transport, power grids and buildings to become more efficient, there must be rules on how, for instance, refrigerators should talk to electricity meters, and thermostats to heating systems.

要让交通、电网和建筑更加高效，必须制定规则，规定如何，比如，让冰箱和恒温器更节能。

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This flow may either be conditional or unconditional; that is, there may be rules that specify conditions that must be met in order for the next activity in the process to be executed.

这个流向可能是有条件的也可能是无条件的；也即，可能有一些指定条件的规则，要执行流程中的下一个活动必须满足这些规则。

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For example, if there is a use case to make a room booking, there must also be computation rules to determine the room charges.

例如，如果有一个用例是进行一个房间预订，也必须有一个计算规则来确定房间费用。

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The promise of America is one immigration policy for all who seek to enter our shores, whether they come from Mexico, Haiti or Canada, there must be one set of rules for everybody.

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There are also intricate rules on how an animal must be slaughtered to produce kosher meat.

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There must be automated systems to identify fraud by the retailer based on basic rules before it sends doubtful transactions to a third party.

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