Eleni Chatzi

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Eleni Chatzi
DSC06784-Edit crop Nlue.jpg
Chatzi in 2024
Alma mater National Technical University of Athens
Occupation Civil Engineer
Known forChair of Structural Mechanics and Monitoring at the Institute of Structural Engineering, ETH Zurich

Eleni Chatzi (born 18 November 1981) is a Greek civil engineer, researcher, and a professor and Chair of Structural Mechanics and Monitoring at the Department of Civil, Environmental and Geomatic Engineering of the Swiss Federal Institute of Technology in Zurich. [1]

Contents

Education

Chatzi obtained her diploma and master's degree MSc in Civil Engineering with honors from the Department of Civil Engineering at the National Technical University of Athens (NTUA). In 2010 she obtained her PhD Degree with distinction from the Department of Civil Engineering & Engineering Mechanics at Columbia University.

Work

In 2010 Chatzi was hired as the youngest assistant professor at ETH Zurich. She was promoted to an associate professor in 2017 [2] [3] and a full professor in 2024. [4] Chatzi works in the domains of Scientific and Physics-Enhanced Machine Learning, building data-driven decision-support tools for structures, infrastructures and engineered systems at-large. Her research follows a hybrid modeling approach, coupling physics-based simulation tools with data stemming from monitoring observations [5] [6] [7] [8] for supporting operators and engineers in the management of their assets. [9] She is an expert in the field of Structural Health Monitoring, with applications extending across a range of systems including civil, mechanical and aerospace structures and components. She has delivered a number of works on the state/parameter [10] [11] [12] state/input [13] [14] and state/input/parameter identification of dynamical systems, [15] relying on novel Bayesian filtering formulations. [16] [17] On the hybrid modeling front, Chatzi's work involves a set of approaches for reducing physics-based simulations, drawing from structural mechanics of complex phenomena (plasticity/nonlinear dynamics/fracture), so that these may be fused with data - possibly on the fly, as data is attained. [18] [19] This includes work on computational hysteretic multiscale schemes, [20] [21] [22] schemes for increasing accuracy and stability in fracture simulations, [23] [24] [25] [26] substructuring schemes [27] [28] as well as Model Order Reduction schemes with parametric dependencies. [29] Chatzi has delivered an array of works on efficient dynamic system metamodels that incorporate uncertainties by employing stochastic and machine learning schemes for the purpose of virtualization/digital twinning, [30] [31] online monitoring and control.

Chatzi further serves as an editor for international journals in the domains of Dynamics and Structural Health Monitoring, including the Journal of Sound and Vibration, Structure & Infrastructure Engineering, the Journal of Structural Engineering, Mechanical Systems and Signal Processing, the Journal of Engineering Mechanics, as well as the Sections on Structural Sensing and Computational Methods in Structural Engineering of Frontiers in Built Environment. From 2016-2021, she served as coordinator of the joint ETH Zürich & University of Zurich PhD Programme in Computational Science. Her work on use of monitoring toward self-aware infrastructures has been honored with the Walter L. Huber Civil Engineering research Prize, awarded by the American Society of Civil Engineering. She is further recipient of the 2020 EASD Junior Research Prize in the area of Computational Structural Dynamics, awarded by the European Association of Structural Dynamics (EASD), the 2023 J.M. Ko Award for excellence in Structural Engineering, and the recipient of the 2024 SHM Person of the Year award, selected by the editors of Structural Health Monitoring: An International Journal.

Awards

Related Research Articles

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References

  1. D-BAUG, Annual Report 2017 (PDF). Zurich: Department of Civil, Environmental and Geomatic Engineering, ETH Zurich. 2017. p. 10-11.
  2. "Department of Civil, Environmental and Geomatic Engineering Annual Report, page 3" (PDF). Archived (PDF) from the original on 6 October 2018.
  3. Anna M. Garry: Inspiring Conversations with Women Professors. Academic Press, 2019, Pages i-iii
  4. "Six professors appointed". ethz.ch. 12 July 2024. Retrieved 25 July 2024.
  5. Klis, Roman; Chatzi, Eleni (24 June 2016). "Vibration Monitoring via Spectro-Temporal Compressive Sensing for Wireless Sensor Networks". Structure and Infrastructure Engineering. 13 (1): 195–209. doi:10.1080/15732479.2016.1198395. S2CID   113423520.
  6. Harmanci, Yunus; Gülan, Utku; Holzner, Markus; Chatzi, Eleni (11 March 2019). "A Novel Approach for 3D-Structural Identification through Video Recording: Magnified Tracking". Sensors. 19 (5): 1229. Bibcode:2019Senso..19.1229H. doi: 10.3390/s19051229 . PMC   6427300 . PMID   30862051.
  7. An, Yonghui; Chatzi, Eleni; Sim, Sung-Han (17 July 2019). "Recent Progress and Future Trends on Damage Identification Methods for Bridge Structures". Structural Control and Health Monitoring. 26 (10). doi: 10.1002/stc.2416 . S2CID   199090262.
  8. Martín-Sanz, Henar; Tatsis, Konstantinos; Dertimanis, Vasileios; Avendaño-Valencia, Luis David; Brühwiler, Eugen; Chatzi, Eleni (3 September 2019). "Monitoring of the UHPFRC strengthened Chillon viaduct under environmental and operational variability". Structure and Infrastructure Engineering. 16 (1): 138–168. doi:10.1080/15732479.2019.1650079. S2CID   203124775.
  9. Schöbi, Roland; Chatzi, Eleni (14 September 2015). "Maintenance planning using continuous-state partially observable Markov decision processes and non-linear action models". Structure and Infrastructure Engineering. 12 (8): 977–994. doi:10.1080/15732479.2015.1076485. S2CID   112606529.
  10. Chatzi, Eleni; Smyth, Andrew (8 December 2008). "The unscented Kalman filter and particle filter methods for nonlinear structural system identification with non-collocated heterogeneous sensing". Structural Control and Health Monitoring. 16 (1): 99–123. doi: 10.1002/stc.290 . S2CID   111057907.
  11. Chatzi, Eleni; Smyth, Andrew; Masri, Sami (1 September 2010). "Experimental application of on-line parametric identification for nonlinear hysteretic systems with model uncertainty". Journal of Structural Safety. 32 (5): 326–337. doi:10.1016/j.strusafe.2010.03.008.
  12. Chatzi, Eleni; Smyth, Andrew (26 September 2014). "Nonlinear System Identification: Particle-Based Methods". Encyclopedia of Earthquake Engineering. pp. 1–18. doi:10.1007/978-3-642-36197-5_79-1. ISBN   978-3-642-36197-5.{{cite book}}: |journal= ignored (help)
  13. Eftekhar-Azam, Saeed; Chatzi, Eleni; Papadimitriou, Costas (1 August 2015). "A dual Kalman filter approach for state estimation via output-only acceleration measurements". Mechanical Systems and Signal Processing. 60–61: 866–886. Bibcode:2015MSSP...60..866E. doi:10.1016/j.ymssp.2015.02.001.
  14. Eftekhar-Azam, Saeed; Chatzi, Eleni; Papadimitriou, Costas; Smyth, Andrew (31 December 2015). "Experimental validation of Kalman-type filters for online and real-time state and input estimation". Journal of Vibration and Control. 23 (15): 2494–2519. doi:10.1177/1077546315617672. S2CID   123607573.
  15. Dertimanis, Vasileios; Chatzi, Eleni; Eftekhar-Azam, Saeed; Papadimitriou, Costas (1 July 2019). "Input-state-parameter estimation of structural systems from limited output information". Mechanical Systems and Signal Processing. 126: 711–746. Bibcode:2019MSSP..126..711D. doi:10.1016/j.ymssp.2019.02.040. S2CID   127933077.
  16. Chatzi, Eleni; Smyth, Andrew (27 September 2012). "Particle filter scheme with mutation for the estimation of time-invariant parameters in structural health monitoring applications". Structural Control and Health Monitoring. 20 (7): 1081–1095. doi: 10.1002/stc.1520 . S2CID   109880910.
  17. Chatzis, Manolis; Chatzi, Eleni (19 October 2017). "A Discontinuous Unscented Kalman Filter for Non-Smooth Dynamic Problems". Frontiers in Built Environment. 3. doi: 10.3389/fbuil.2017.00056 . hdl: 20.500.11850/237574 . S2CID   38951377.
  18. Lai, Zhilu; Mylonas, Charilaos; Nagarajaiah, Satish; Chatzi, Eleni (15 September 2021). "Structural identification with physics-informed neural ordinary differential equations". Journal of Sound and Vibration. 508: 116196. Bibcode:2021JSV...50816196L. doi:10.1016/j.jsv.2021.116196. hdl: 20.500.11850/488395 .
  19. Agathos, Konstantinos; Tatsis, Konstantinos; Nicoli, Sergio; Bordas, Stéphane; Chatzi, Eleni (1 April 2021). "Crack detection in Mindlin-Reissner Plates under dynamic loads based on fusion of data and models". Computers and Structures. 246: 106475. doi:10.1016/j.compstruc.2020.106475. S2CID   233529394.
  20. Triantafyllou, Savvas P.; Chatzi, Eleni N. (2015). "Towards a Multiscale Scheme for Nonlinear Dynamic Analysis of Masonry Structures with Damage". Seismic Assessment, Behavior and Retrofit of Heritage Buildings and Monuments. Computational Methods in Applied Sciences. Vol. 37. pp. 165–198. doi:10.1007/978-3-319-16130-3_7. ISBN   978-3-319-16129-7.
  21. Triantafyllou, Savvas P.; Chatzi, Eleni N. (September 2014). "A hysteretic multiscale formulation for nonlinear dynamic analysis of composite materials". Computational Mechanics. 54 (3): 763–787. Bibcode:2014CompM..54..763T. doi: 10.1007/s00466-014-1032-2 . hdl: 20.500.11850/88666 .
  22. Egger, Adrian; Triantafyllou, Savvas; Chatzi, Eleni (June 2019). "A scaled boundary multiscale approach to crack propagation". Proceedings of the 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures. doi:10.21012/FC10.233540. S2CID   197577410.
  23. Agathos, Konstantinos; Ventura, Giulio; Chatzi, Eleni; Bordas, Stéphane P. A. (13 January 2018). "Stable 3D XFEM/vector level sets for non-planar 3D crack propagation and comparison of enrichment schemes: Stable 3D XFEM/vector-level sets for nonplanar 3D crack propagation and comparison of enrichment schemes". International Journal for Numerical Methods in Engineering. 113 (2): 252–276. doi:10.1002/nme.5611. S2CID   125478080.
  24. Egger, Adrian W.; Chatzi, Eleni N.; Triantafyllou, Savvas P. (October 2017). "An enhanced scaled boundary finite element method for linear elastic fracture". Archive of Applied Mechanics. 87 (10): 1667–1706. Bibcode:2017AAM....87.1667E. doi:10.1007/s00419-017-1280-7. S2CID   126052740.
  25. Agathos, Konstantinos; Chatzi, Eleni; Bordas, Stéphane P.A. (July 2016). "Stable 3D extended finite elements with higher order enrichment for accurate non planar fracture". Computer Methods in Applied Mechanics and Engineering. 306: 19–46. Bibcode:2016CMAME.306...19A. doi:10.1016/j.cma.2016.03.023.
  26. Agathos, Konstantinos; Chatzi, Eleni; Bordas, Stéphane P. A.; Talaslidis, Demosthenes (2 March 2016). "A well-conditioned and optimally convergent XFEM for 3D linear elastic fracture: XFEM WITH GLOBAL ENRICHMENT". International Journal for Numerical Methods in Engineering. 105 (9): 643–677. doi:10.1002/nme.4982. S2CID   120955771.
  27. Tatsis, Konstantinos; Dertimanis, Vasilis; Abdallah, Imad; Chatzi, Eleni (2017). "A substructure approach for fatigue assessment on wind turbine support structures using output-only measurements". Procedia Engineering. 199: 1044–1049. doi:10.1016/j.proeng.2017.09.285. hdl: 20.500.11850/227958 .
  28. Tatsis, Konstantinos.E.; Dertimanis, Vasils K.; Papadimitriou, Costas; Lourens, Eliz-Mari; Chatzi, Eleni N. (March 2021). "A general substructure-based framework for input-state estimation using limited output measurements". Mechanical Systems and Signal Processing. 150: 107223. Bibcode:2021MSSP..15007223T. doi:10.1016/j.ymssp.2020.107223. hdl: 20.500.11850/442907 . S2CID   224969018.
  29. Agathos, Konstantinos; Vlachas, Konstantinos; Garland, Anthony; Chatzi, Eleni (30 May 2024). "Accelerating structural dynamics simulations with localised phenomena through matrix compression and projection-based model order reduction". International Journal for Numerical Methods in Engineering. 125 (10). Bibcode:2024IJNME.125E7445A. doi:10.1002/nme.7445. hdl: 20.500.11850/660095 . ISSN   0029-5981.
  30. Simpson, Thomas; Dervilis, Nikolaos; Chatzi, Eleni (October 2021). "Machine Learning Approach to Model Order Reduction of Nonlinear Systems via Autoencoder and LSTM Networks". Journal of Engineering Mechanics. 147 (10). arXiv: 2109.11213 . doi:10.1061/(ASCE)EM.1943-7889.0001971. ISSN   0733-9399.
  31. Vettori, S.; Di Lorenzo, E.; Peeters, B.; Chatzi, E. (May 2024). "Assessment of alternative covariance functions for joint input-state estimation via Gaussian Process latent force models in structural dynamics". Mechanical Systems and Signal Processing. 213: 111303. arXiv: 2306.16302 . Bibcode:2024MSSP..21311303V. doi:10.1016/j.ymssp.2024.111303.
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