Assessing Engineering Resilience for Systems with Multiple Performance Measures

Abstract

Recently, efforts to model and assess a system's resilience to disruptions due to environmental and adversarial threats have increased substantially. Researchers have investigated resilience in many disciplines, including sociology, psychology, computer networks, and engineering systems, to name a few. When assessing engineering system resilience, the resilience assessment typically considers a single performance measure, a disruption, a loss of performance, the time required to recover, or a combination of these elements. We define and use a resilient engineered system definition that separates system resilience into platform and mission resilience. Most complex systems have multiple performance measures; this research proposes using multiple objective decision analysis to assess system resilience for systems with multiple performance measures using two distinct methods. The first method quantifies platform resilience and includes resilience and other "ilities" directly in the value hierarchy, while the second method quantifies mission resilience and uses the "ilities" in the calculation of the expected mission performance for every performance measure in the value hierarchy. We illustrate the mission resilience method using a transportation systems-of-systems network with varying levels of resilience due to the level of connectivity and autonomy of the vehicles and platform resilience by using a notional military example. Our analysis found that it is necessary to quantify performance in context with specific mission(s) and scenario(s) under specific threat(s) and then use modeling and simulation to help determine the resilience of a system for a given set of conditions. The example demonstrates how incorporating system mission resilience can improve performance for some performance measures while negatively affecting others.

Set‐based design: The state‐of‐practice and research opportunities

“…Early Group A documents focused heavily on describing the SBD process and potential benefits, using Toyota's design and production process as the exemplar case study 2,3,25,26 . Later, the research focus transitioned from describing SBD to developing and applying methodologies, first against component and small system design problems, 4,11,38,44 and subsequently complex system design problems in various engineering fields 6,7,45,63,64 . As with Group A, we observe a similar trend toward complex system design in the Group B documents.…”

“…From this set, we identified and collected only refereed journal articles and conference papers, reducing the set to the 64 SBD specific documents considered in the final review. We refer to this set of documents as Group A throughout the remainder of this paper 2–65 . We provide the complete listing for all Group A documents in Table 1.…”

“…For example, the research describing the SBD enabled development of the ship‐to‐shore connector, amphibious combat vehicle, and the small surface combatant used quantitative tools, but the methodologies were largely qualitative in application 6,21,50 . On the other hand research published by Rapp et al in 2018 and Specking et al in 2019 provide typical examples of quantitative SBD methodologies 15,64 . Therefore, in assessing SBD's state‐of‐practice, we analyze the proportion of quantitative and qualitative methodologies.…”

Analyzing Mission Impact of Military Installations Microgrid for Resilience

“…Recent resilience analysis work within a military systems context has focused on breaking resilience up into multiple phases of a system design and operation process with associated terminologies to suit each phase of a system's life cycle [41,42] and across multiple methods of increasing resilience in a system [43]. Further, there have been arguments made to use resilience in analysis of alternatives for military systems [44] and from a mission engineering perspective [45]. Our proposed measure is similar to the value-oriented measure described by Ferris [46,47], except we provide a means to define value as mission impact, whereas Ferris presented a general framework.…”

The Need to Reconcile Concepts that Characterize Systems Facing Threats

“…Specking et al. (2019) relate resilience to “ilities” like reliability, availability, and maintainability that help the system achieve performance through accomplishing its designed tasks. Creaco, Franchini, and Todini (2016) found resilience to be part of an indirect measure of reliability.…”