09.26.25 Dr. Spilios D. Fassois – University of Patras
Time series based robust damage and fault diagnosis for engineering structures and systems under uncertainty
Date: September 26, 2025; Time: 2:30 PM Location: PWEB 175
Abstract: The problem of damage and fault diagnosis for structures and engineering systems operating under uncertainty is addressed via statistical time series based methods. A critical overview of the main principles, underlying assumptions, and available approaches is presented. The issue of robustness, arising from the need for counteracting the effects of uncertainty, including that due to varying Environmental and Operational Conditions (EOCs) and populations of similar structures and systems, is demonstrated. The main approaches for achieving robustness are presented, with emphasis on conceptual and practical simplicity, ease of use, operation with a low number of sensors and limited numbers of training signals, physical interpretability, and the achievement of high-performance even for early faults. The novel holistic Functional Model (FM) based method, within which the subproblems of damage/fault detection, precise localization, and level estimation may be seamlessly integrated, is then introduced and its various forms are discussed. Application case studies, pertaining to damage diagnosis for engineering structures and systems under uncertainty are presented, with diagnostic performance systematically assessed. The presentation concludes with remarks on the status of the technology and future perspectives.
Biographical Sketch: Spilios Fassois is Professor and Founding Director of the Stochastic Mechanical Systems and Automation (SMSA) Laboratory at the University of Patras, Greece. He previously served on the faculty of the University of Michigan – Ann Arbor. His research interests include stochastic mechanical and aeronautical systems, statistical time series methods, data-based modeling, diagnostics, Structural Health Monitoring, and Machine Learning with applications on structural, vehicular, aeronautical, and other engineering systems. He is the recipient of the 2023 `Evangelos Papanoutsos Excellence in Teaching Award’ at the University of Patras, the 1990 `Excellence in Teaching Award of the College of Engineering’ at the University of Michigan, and various other awards and distinctions. He is Editor-in-Chief for the Journal of Mechanical Systems and Signal Processing (MSSP), Board Member for additional international journals, and Scientific Committee member for numerous international conferences. He has given numerous Keynote and other invited presentations, has organized 5 Thematic Issues for esteemed international journals, and published over 320 articles in technical journals, conference proceedings, and encyclopedias, with his work being supported by industry and national/international funding agencies.
10.10.25 Dr. Sean Bradshaw – Pratt & Whitney
Powering the Future
Date: October 10, 2025; Time: 2:30 PM Location: PWEB 175
Abstract: Projected demand growth in the aviation sector over the next quarter century is driving the need for greater aircraft fuel efficiency and lower noise footprint. This presentation will provide a brief overview of Pratt & Whitney’s approach to powering the future of flight, including geared turbofans, hybrid-electric propulsion, technical evaluations of synthetic aviation fuels, and supporting industry collaborations through ASTM on rigorous standards that would enable the commercial use of 100% synthetic aviation fuels.
Biographical Sketch: Dr. Sean Bradshaw is a senior technical fellow at Pratt & Whitney, where his primary focus is the development of advanced propulsion technologies that will power the future of flight. Pratt & Whitney is a world leader in the design, manufacture, and service of aircraft engines and auxiliary power units. He also provides strategic and technical leadership to the aviation industry by serving as: the chair of the ASME Committee on Sustainability, an associate editor of the ASME Journal of Engineering for Gas Turbines and Power, a member of the ASME Heat Transfer Committee, and a member of the Aeronautics & Space Engineering Board of the National Academies of Sciences, Engineering, and Medicine. Sean earned a B.S., an M.S., and a Ph.D. in Aeronautics & Astronautics from the Massachusetts Institute of Technology.
10.24.25 Dr. Jaime C. Grunlan – Texas A&M University
Protective Nanocoatings from Polyelectrolytes: Flame Retardancy, Gas Barrier, and High Voltage Insulation
Date: October 24, 2025; Time: 2:30 PM Location: PWEB 175
Abstract: Layer-by-layer (LbL) assembly is a conformal coating technology capable of imparting a multiplicity of functionalities on nearly any type of surface in a relatively environmentally friendly way. At its core, LbL is a solution deposition technique in which layers of cationic and anionic materials (e.g. nanoparticles, polymers and even biological molecules) are built up via electrostatic attractions in an alternating fashion, while controlling process variables such as pH, coating time, and concentration. Here we are producing nanocomposite multilayers (50 – 1000 nm thick), having 10 – 96 wt% clay, that can be completely transparent, stop gas permeation, and impart extreme heat shielding to carbon fiber reinforced polymer composites. Similar multilayer coatings exhibit very high dielectric breakdown strength and good thermal conductivity, for protection of high voltage electronics. In an effort to impart flame retardant behavior to fabric using fewer processing steps, a water-soluble polyelectrolyte complex (PEC) was developed. This nanocoating is comprised of polyethylenimine and poly(sodium phosphate) and imparts self-extinguishing behavior to cotton fabric in just a single coating step. Adding a melamine solution to the coating procedure as a second step renders nylon-cotton blends self-extinguishing. A PEC of PEI and polyacrylic acid is able to achieve an oxygen transmission rate below 0.005 cm3/m2/day at 100%RH and a thickness of just 2 m. This is an all-polymer foil replacement technology. Examples of bio-based polyelectrolytes (e.g., chitosan and phytic acid), being used for these same applications, will be shown. These coating techniques can be deposited using roll-to-roll processing (e.g., flexographic printing, dip-coating, or spray-coating). Opportunities and challenges will be discussed. Our work in these areas has been highlighted in C&EN, ScienceNews, Nature, Smithsonian Magazine, Chemistry World and various scientific news outlets worldwide. For more information, please visit my website: https://grunlan-nanocomposites.com/
Biographical Sketch: Dr. Jaime Grunlan is the Leland T. Jordan ’29 Chair of Mechanical Engineering at Texas A&M University, where he has worked for more than 20 years. He holds joint appointments in the Department of Materials Science and Engineering and the Department of Chemistry. He is a world leader in organic thermoelectric materials, super gas barrier layers, and environmentally-benign, flame retardant nanocoatings. He holds 17 issued U.S. patents and several EU patents. He has published more than 230 journal papers, with more than 29,000 citations. His work has been highlighted in Smithsonian Magazine, Nature, and the New York Times. He is an Editor of the Journal of Materials Science and Progress in Organic Coatings, and Associate Editor of Green Materials. In 2018, Prof. Grunlan became a Fellow of the American Society of Mechanical Engineers (FASME) and was awarded a doctorate honoris causa (i.e. honorary doctorate) from the University of South Brittany (Lorient, France). In 2023, he became a Fellow of the American Chemical Society (FACS). In 2024, he became Fellow of the Polymer Chemistry (POLY) and Polymeric Materials: Science and Engineering (PMSE) Divisions of ACS. He also became a Fellow of the National Academy of Inventors (FNAI) in 2024.