01856nam a22001337a 4500082000800000100002700008245009300035264003500128300002500163500140500188650003601593700003601629856005701665 a621 a Ali, Muhammad Junaid  aOptimal Expansion of Interface Dynamics for Substructure Coupling /cMuhammad Junaid Ali aIslamabad :bIslamabad :c2025 a251p.bsoft copyc30 aThis thesis introduces a novel methodology for optimal interface expansion in dynamic substructuring, focusing on inaccessible and continuous interfaces. Unlike traditional approaches relying on modal parameters from Frequency Response Functions (FRFs), it employs a direct frequency-based method targeting interface Degrees of Freedom (DoFs), bypassing errors linked to modal identification. The System Equivalent Model Mixing (SEMM) technique is utilized to expand dynamics at the interface by integrating numerical and experimental models into a mixed model. Coherence is employed as a robust correlation metric, evaluating both phase and magnitude of FRFs. This research addresses optimal sensor placement (OSP) for effective expansion, testing nineteen stochastic metaheuristics categorized into swarm intelligence, surrogate algorithms, and physicsinspired methods to alleviate computational challenges of exhaustive searches. The Mountain Gazelle Optimizer (MGO) algorithm proved highly efficient for larger systems, while exhaustive search was effective for smaller cases. Validation involved cantilevered beam models and experimental setups, demonstrating strong correlation at interface DoFs. MGO proved to be 49 times faster than exhaustive search in identifying optimal sensor locations. The proposed methodology showcases practical applicability in achieving accurate dynamic expansions. aMS Mechanical Engineering  aSupervisor: Dr. Muhammad Safdar uhttp://10.250.8.41:8080/xmlui/handle/123456789/53336