2. Identify the four essential parts for the realization of FPU

For a technical system to achieve its UPF, it must have four essential parts which individually and collectively fulfill their role in its operation. These parts must be identified in the existing technical object, or associated for the first time in the case of a study of a technical object which does not yet exist, but whose UPF has already been defined.

You need to identify these four parts in the sense that they form a whole by virtue of their association, and that this association gives rise to the FPU. When this whole is fully defined, we no longer speak of a tool but of a "technical system", because the element studied no longer appears in isolation. It becomes an association of elements producing a function in addition to the simple addition of the respective functions of the parts. This association is referred to as a "system" effect.

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