Fuzzy Multiple Criteria Workflow Robustness and Resiliency Modeling with Petri Nets

The increasing complexity and tight coupling between people and computer systems in military operations has led to improved efficiency, as well as greater vulnerability due to system failure. Careful management of workflow systems can minimize operational vulnerability in command and control. Tavana et al. (2011) developed a workflow management framework capable of both modeling structure and providing a wide range of quantitative analysis with high-level Petri nets (PNs). The framework is based on a sustainability index that captures the concepts of self-protecting and self-healing systems. This index uses crisp numerical values to measure the robustness and resiliency of the system. However, the observed values of data in real-world military operations are often imprecise or vague. These inexact data can be represented by fuzzy numbers to reflect the decision makers’ intuition and subjective judgments. In this paper, the authors extend this model to a fuzzy framework by proposing a new fuzzy workflow modeling system with PNs. The new model plots the fuzzy robustness and resiliency measures in a Cartesian coordinate system and derives an overall fuzzy sustainability index for the system based on the theory of displaced ideals. The proposed model also considers multiple criteria to produce this fuzzy index.