From TRL to SRL: The Concept of System Readiness Levels
Sauser, B., D. Verma, J. Ramirez-Marquez, and R. Gove. 2006. "From TRL to SRL: The Concept of System Readiness Levels." Proceedings of the Conference on Systems Engineering Research (CSER), April 7-8, 2006, Los Angeles, CA, USA.
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In this paper the authors propose the concept of a system readiness level (SRL) index that is dynamically calculated by combining the current technology readiness level (TRL) scale with the concept of integration readiness level (IRL). The paper presents the foundations of the SRL and methodology for developing, validating, and verifying the operational use of the SRL index. The SRL model presented in the paper is the first step in a contingency model for systems engineering that is built on the fundamental theory of a system.