PSI - Issue 80

Sadjad Naderi et al. / Procedia Structural Integrity 80 (2026) 77–92 Sadjad Naderi et al. / Structural Integrity Procedia 00 (2025) 000–000

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We propose that three networks should be integrated as cognitive and operational components: physical assets, digital modules, and humans operating at multiple system levels . This approach aligns with emerging Human-Cyber Physical Systems (HCPS) frameworks (Khamaisi et al. 2025; Zhou et al. 2019), which recognise humans as integral system components with distinct capabilities and decision-making processes. In the aerospace structural health monitoring context, this encompasses designers and analysts at the design level (interpreting DT outputs for design modifications and model validation), maintenance engineers at the operational level (executing DT-informed inspection schedules and providing damage state feedback), and pilots (modifying flight parameters based on structural health status and reporting anomalous behaviour). HCPS integration enables bidirectional information flow and distributed decision-making across system levels. Acknowledgements The authors acknowledge funding from the AVATAR project through the European Climate, Infrastructure and Environment Executive Agency (CINEA) under Grant Agreement No. 101096073, and from United Kingdom Research and Innovation (UKRI) under the UK Government's Horizon Europe Guarantee scheme through Grant Agreement No. 10065739. References Chia, Joelle WY, Wim JC Verhagen, Jose M Silva, and Ivan S Cole. 2024. "A review and outlook of airframe digital twins for structural prognostics and health management in the aviation industry." Journal of Manufacturing Systems 77:398-417. Fierro, Gian Piero Malfense, and Michele Meo. 2015. "Residual fatigue life estimation using a nonlinear ultrasound modulation method." Smart Materials and Structures 24 (2):025040. Khamaisi, Riccardo Karim, Margherita Peruzzini, Roberto Raffaeli, Giancarlo Mangia, and Marcello Pellicciari. 2025. "Designing adaptive human cyber-physical systems to improve industrial tasks: a methodological approach." The International Journal of Advanced Manufacturing Technology 136 (9):4067-4082. Lim, Hyung Jin, and Hoon Sohn. 2019. "Online fatigue crack prognosis using nonlinear ultrasonic modulation." Structural Health Monitoring 18 (5-6):1889-1902. Morse, Llewellyn, Zahra Sharif Khodaei, and MH Aliabadi. 2019. "A multi-fidelity modelling approach to the statistical inference of the equivalent initial flaw size distribution for multiple-site damage." International Journal of Fatigue 120:329-341. Murphy, Kevin Patrick. 2002. Dynamic bayesian networks: representation, inference and learning : University of California, Berkeley. Pan, Yuhang, Zahra Sharif Khodaei, and Ferri MH Aliabadi. 2025. "In-service fatigue crack monitoring through baseline-free automated detection and physics-informed neural network quantification." NDT & E International 153:103360. Paris, Paul, and Fazil Erdogan. 1963. "A critical analysis of crack propagation laws." Journal of basic engineering 85 (4):528-533. Ray, Asok, and Sekhar Tangirala. 2002. "Stochastic modeling of fatigue crack dynamics for on-line failure prognostics." IEEE Transactions on Control Systems Technology 4 (4):443-451. Sherstinsky, Alex. 2020. "Fundamentals of recurrent neural network (RNN) and long short-term memory (LSTM) network." Physica D: Nonlinear Phenomena 404:132306. Sisson, William, Pranav Karve, and Sankaran Mahadevan. 2022. "Digital twin for component health-and stress-aware rotorcraft flight control." Structural and Multidisciplinary Optimization 65 (11):318. Thelen, Adam, Xiaoge Zhang, Olga Fink, Yan Lu, Sayan Ghosh, Byeng D Youn, Michael D Todd, Sankaran Mahadevan, Chao Hu, and Zhen Hu. 2023. "A comprehensive review of digital twin—part 2: roles of uncertainty quantification and optimization, a battery digital twin, and perspectives." Structural and multidisciplinary optimization 66 (1):1. Tuegel, Eric J, Anthony R Ingraffea, Thomas G Eason, and S Michael Spottswood. 2011. "Reengineering aircraft structural life prediction using a digital twin." International Journal of Aerospace Engineering 2011 (1):154798. Wang, Jie. 2023. "An intuitive tutorial to Gaussian process regression." Computing in Science & Engineering 25 (4):4-11. Zhou, Ji, Yanhong Zhou, Baicun Wang, and Jiyuan Zang. 2019. "Human–cyber–physical systems (HCPSs) in the context of new-generation intelligent manufacturing." Engineering 5 (4):624-636.