Conceptually, the entire business from first customer contact, through completion of the work and payment of the bill, represents a single, macro-level unit of work, with a lifetime of days to weeks.

从概念上讲，从第一次顾客联系到完成工作和帐单支付的整个业务表示单个宏观层次的工作单元，并具有数天到数周不等的生命周期。

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The first level consists of the performance object, which is a unit that can model a physical device or abstract component in a system.

第一级包括性能对象，它是可以为物理设备建模，或者抽象系统中组件的单元。

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The author has put forward a theory while describing the first level, which thinks that the personality of the unit is a kind of "individual liability".

在第一个层次中提出了单位人格由财产和职位构成理论，认为单位犯罪刑事责任是一种“个人责任”；

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It was only a matter of time before the hydrogen reached a level where it would detonate, and one after another, the first unit, then the third unit, and finally the second unit, suffered hydrogen explosions that blew off the steel panels and left the top of the reactor building exposed.

FORBES: Explainer: What Caused The Incident At Fukushima-Daiichi