Hyunsun Lee

Statistical data analysis; Stochastic branching process in wireless ad-hoc network; Sound generation mechanism for aircraft engine nozzle; Homogenization for heterogeneous composites; Rayleigh-Taylor instabilities

Postdoctoral Fellowship, Mathematics, Florida State University

Postdoctoral Fellowship, Center for Simulation of Advanced Rockets, University of Illinois at Urbana-Champaign

Ph.D., Applied Mathematics and Statistics, Stony Brook University

B.S., M.S., Mathematics, Yonsei University, Seoul, South Korea

Completion, Foreign Language Institute, Yonsei University, Seoul, South Korea

Dr. Lee’s research interest is focused on mathematical modeling and data analysis in practical problems, broadly encompassed in Statistics, Computer Science, Solid Mechanics, Acoustics and Fluid Dynamics. In her current research, she developed pre- and self-diagnostic models for a syndrome using machine learning techniques with her students. The other ongoing topic in Computer Science is to develop an optimized routing algorithm for wireless ad-hoc networks based on a stochastic branching process that is often used to assess the early stage of an infectious disease outbreak. She also has interdisciplinary research experience in other engineering fields throughout her career. In Acoustics, the source of aircraft noise in turbulent flow region near the nozzle tip was identified by investigating the underlying physics of sound generation mechanism. The sound source term of Lighthill's equation was decomposed into sub-terms and the sub-terms were correlated to the far-field sound to identify the sound source. It possibly brings a better understanding of noise control devices when the study is applied to different nozzle configurations. In the topic of Solid Mechanics, a classical theory, Hashin-Shtrikman variational principle, and its reformulations were applied to various heterogeneous particulate composites, such as rocket propellants, granular media etc. Optimized statistical tools were developed to capture more precise morphological information of the materials, based on the images that were from either computer simulation or micro-tomography. In Fluid Dynamics, Rayleigh-Taylor instability which occurs when a dense, heavy fluid is accelerated by a light fluid by gravity, penetrating into the other, followed by the development of a complex mixing layer, was studied for her dissertation. Closure models of averaged interfacial quantities were proposed and validated based on direct numerical simulations (DNS).

• Machine-aided self-diagnostic prediction models for polycystic ovary syndrome: observational study (Angela Zigarelli, Ziyang Jia and Hyunsun Lee, Journal of Medical Internet Research Formative Research, 2022)
• A stochastic process based routing algorithm for wireless ad hoc networks (Hyunsun Lee, Yi Zhu, Donald Wapenski, Xi Wang, Qiong Zhang, Paoarao Palacharla, and Tadashi Ikeuchi, IEEE ICNC, 2019)
• Stochastic and spatio-temporal analysis of the Middle East Respiratory Syndrome outbreak in South Korea, 2015 (Hyunsun Lee, Infectious Disease Modelling, volume 4, pp. 227-238, 2019)
• Identification of jet noise source based on high-fidelity numerical simulation of a round jet flow (Hyunsun Lee, Ali Uzun and Yousuff M. Hussaini, International Journal of Aeroacoustics, volume 16. issue 1-2, pp. 78-96, 2017)
• Computing overall elastic constants of polydisperse particulate composites from micro-tomographic data (Hyunsun Lee, Andrew S. Gillman and Karel Matous, Journal of the Mechanics and Physics of Solids, volume 59 (9), 2011)
• Three-dimensional reconstruction of statistically optimal unit cells of polydisperse particulate composites from microtomography (Hyunsun Lee, Mark Brandyberry, Andrew Tudor and Karel Matous, Physical Review E, 2009)
• On validation of turbulent mixing simulations for Rayleigh-Taylor instability (Hyunsun Lee, Hyeon- seong Jin, Yan Yu and James Glimm, Physics of Fluids, volume 20, issue 1, 2008)