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The MBSE Process: Inputs and Outputs

Systems Engineering Process

System Specs &  Custom Reports

Expertise

Source Documents

The systems engineering process needs to support top‐down, middle‐out, and reverse engineering approaches to system  specification and design. System Design Model

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Model Essential Characteristics

A system is a whole that cannot be divided into independent parts without  losing its essential characteristics as a whole. It follows from this definition that, a system’s essential defining properties are  the product of the interactions of its parts, not the actions of the parts  considered separately. Therefore, when a system is taken apart, or its parts are considered  independently of each other, the system loses its essential properties.

Furthermore, when performance of each part taken separately is improved,  the performance of the system as a whole may not be, and usually isn’t.

‐‐Russell Ackoff

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