Seeing Complex System through Different Lenses: Impact of Decomposition Perspective on System Architecture Analysis

Abstract

Creating a representation of the base system architecture is one of the first and most critical steps for system development. Typically, the system architect would start by decomposing the existing or proposed system into smaller subsystems or modules. It is widely recognized that at the overall systems level a system can be viewed from different viewpoints. However, unlike often assumed, also when focusing on a single view, such as a systems view, the system decomposition can be done in many alternative ways thus resulting in a different base architecture every time. Depending on the system architect's perspective, representation of system can vary widely, having a profound impact on subsequent system architecture development. In this paper, quantitative analysis of system architecture representation, using a design structure matrix (DSM), and its effect on system modularity is presented. The analysis reveals that the results of the system analysis, namely modularity, are different for the same system, depending on the system architect's perspective. This work highlights the need for more structured approaches to system decomposition and system analysis based on that decomposition. C⃝ 2014 Wiley Periodicals, Inc. Syst Eng

A computational concept generation method for a modular vehicle fleet design

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Design structure matrix‐based modularization approach for complex systems with multiple design constraints

“…However, owing to the different preferences of various stakeholders and system design constraints, it is often extremely difficult to generate a system decomposition configuration that satisfies all the needs from stakeholders and the imposed constraints. In fact, it has been quantitatively demonstrated that the perspectives of stakeholders of the system can significantly change the final decomposition of the system …”

Entropy‐based system assessment metric for determining architecture's robustness to different stakeholder perspectives

“…The Department of Defense Architectural Framework (DoDAF) addresses this issue for weapons systems wherein the system architecture has been organized from systems, operational, and technical viewpoints . This idea was generalized and refined as three unique architectural decomposition perspectives: function, assembly, and maintenance‐based decompositions . The initial decomposition process is executed by designers and system architects on a functional basis, and the decomposition is extended to increase the level of granularity of the decompositions .…”

“…The initial decomposition process is executed by designers and system architects on a functional basis, and the decomposition is extended to increase the level of granularity of the decompositions . However, in complex systems, decomposing a product into its atomic constituents is highly impractical . To this end, the granularity of the system decomposition should be fine enough to differentiate viewpoints of various perspectives (e.g., assembly and maintenance), yet not too fine to be impractical .…”

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