Systems Engineering

In software engineering and even more in the more general discipline of systems engineering is every construction of a system embedded in an overall engineering process. For the discussion in this paper, a small subset of one of these standards is selected, namely the systems engineering handbook of INCOSE [64], ISO/IEC 1220-2005 [69], ISO/IEC 15288:2008 [70] as well as ISO/IEC 16326-2009 [71]. The text of this lecture follows these standards but gives a different emphasis. This text concentrates on the technical aspect of this process, and within this technical aspect on the implicit logic of the symbolic representation of the process (cf. [42], [43] and figure 2.1).

Figure 2.1: Minimal Elements of the Technical Systems Engineering Process

Summarizing the main points one has to state that in this text the following special emphasis is realized:

1. Phases: Four phases are assumed: P (problem introduction), R (requirements engineering), M (modeling a system function) and I (implementation). The bigger those projects are the sooner will these four phases iteratively/ cyclic be repeated several times. The whole process includes additionally meta dimension like verification (review of the formal correctness and plausibility of the formal system model according to specified requirements), validation (review of the correctness and plausibility of the final system, using the previously created specifications and feedback from the client (stakeholder).

2. Theory: Whatever will be designed by an engineering process, it must be described adequately by appropriate theoretical (formal / mathematical) models. This theoretical account must allow predictions and formal proofs.

3. Software: What ever will be presented at the end as a result, every type of system can be differentiated with regard to software and those components that are controlled by the software. Here, all these components are considered as 'interface' between the user and the software. Therefore, the software is logically considered the most crucial component (even if in individual cases may be very high practical knowledge about materials, material processing, material behavior, etc., can be necessary to enable the working of the system). The methodical development of software based on a suitable theory plays therefore a central role.

A more detailed description is given below.