Guest Open Lecture on Structural Analysis under Hybrid Uncertainties
Speaker: Dr. Alba Sofi, Associate Professor. Department of Architecture and Territory University “Mediterranea” of Reggio Calabria, Italy.
Date & Location: Tuesday July 9, 2024, 09.00 h. Senatssitzungssaal, Room 503 / Geschossbau I. It is possible to join via zoom. Please register here.
Abstract
The appropriate mathematical description and processing of uncertainties affecting model parameters and external excitations is critical to achieve an accurate and robust assessment of systems performance. Nowadays, uncertainty models are commonly cast within a generalized framework including probabilistic, non-probabilistic (interval model, fuzzy sets, etc.), and mixed or hybrid probabilistic/non-probabilistic approaches. This lecture focuses on the analysis of structural systems involving hybrid uncertainties, which result from a mixture of interval and probabilistic models. Depending on the sources of uncertainty and their mathematical description, three different cases are examined: i) structural parameters modeled as imprecise random variables characterized by a probability density function with interval basic parameters; ii) structural parameters described as interval variables and external excitation modeled as a stochastic process; iii) external excitation represented as an imprecise stochastic process characterized by a power spectral density function with interval parameters. In each case, efficient strategies able to decouple the propagation of interval and random uncertainties are presented. A two-level propagation of imprecise random variables is performed by applying a Response Surface approach. Structural safety assessment in the presence of stochastic excitation and interval (structural or spectral) parameters is efficiently carried out by interval extension of the classical first-passage problem. Based on the presented theoretitical and computational developments, the capability of hybrid uncertainty models to provide a unified treatment of epistemic and aleatory uncertainties in engineering problems is discussed.
About the speaker
Prof. Alba Sofi holds the position of Associate Professor of Mechanics of Solids and Structures at the University of Reggio Calabria, Italy. She obtained her Ph.D. degree in Structural Engineering from the University of Palermo, Italy. Following her doctoral studies, she continued her research as a Post-Doctoral Fellow at the University of Messina and later as a Research Assistant at the University of Reggio Calabria (Italy). Her international engagements include serving as a Visiting Fellow at Oxford University and at the University of New South Wales in Australia. Additionally, she held visiting professorships at Guangzhou University and Xidian University in China. Prof. Sofi actively contributes to the academic community through editorial roles. She serves as Managing Editor for the ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part B: Mechanical Engineering. Notably, she received the Editor’s Award for the best paper in 2020 in the ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part B: Mechanical Engineering. Her commitment to international collaboration is evident through her co-chairing of the 9th International Workshop on Reliable Engineering Computing (REC 2021). Additionally, she actively participates in various scientific commifees for international conferences. Prof. Sofi’s research interests encompass several areas, including stochastic dynamics, uncertainty quantification (UQ), computational mechanics, bridge-vehicle dynamic interaction, cable dynamics, fractional calculus, and non-local elasticity theory. With an extensive publication record (over 100 publications in peer-reviewed journals and conference proceedings) and involvement in research projects supported by the Italian Ministry of Universities and Research, she is widely recognized for her contributions to the field of mechanics of solids and structures.