Education 2000: Massachusetts Institute of Technology, Masters of Science, Civil Engineering/ Geotechnical, GPA 4.64/5.00 1997: University of Massachusetts Lowell, BSE, Civil Engineering, GPA 3.64/4.00 Work Experience 2000 - 2006: Leading Geotechnical Firm inNew York, NY, Structural engineer: Involved in design of bridge foundations, cut and cover or rock mined tunnels, deep excavations, finite element simulations, piers and bulkheads, pile foundations, and field inspection. Presented internal presentations for finite element simulations, lateral pile capacity methods. 1998 -2000: Massachusetts Institute of Technology, Cambridge MA, Graduate research assistant: Researched and summarized the performance of nearly 30 slurry wall supported excavations in the United States. 1994 -1998: Centers for Learning, University of Massachusetts Lowell, Tutor: Hired by the University as a professional tutor. Assisted students and organized exam reviews for more than 15 subjects in science, math, and engineering 1998 - Summer: City Hall of Trikala, Greece, Surveyor: Performed surveying and road layout duties. 1997 - Summer: Public Power Corporation of Greece, Mesohora Hydroelectric Project, Engineer in Training: Representative Project & Design Experience Excavations: 300 Madison Avenue, NY, Newtown Creek, NY, Paerdegat Basin, NY, Times Square, NY, (also see slurry walls), Harbor at Hastings, NY, 53rd Street & Lexington Avenue NY. Marine: Bulkhead at Newtown Creek, NY, Port Elizabeth, NJ, Hudson River Piers. Piling: Drilled minipiles: DOMAC MA, Peerless Importers NY, Metro North NY, MA, 7 World Trade Center, NY, Driven Piles: JFK Air Train, NY, Maher Terminals, NJ, Newport Office Center Evaluation. Slope Stability: Newtown Creek, NY, Chevron-Texaco site, NJ, Maher Terminals, NJ. Slurry Walls: Boston, MA: 500 Boylston, 75 State Street, Beth Israel Deaconess Hospital, Dana Farber Tower (Smith Laboratories), Flagship Wharf, Millennium Place, One Memorial Drive, Post Office Square Garage, State Transportation Bldg. Chicago, IL: Amoco Standard Oil, AT&T Corporate Center, Guest Quarters Hotel, Northwester University Memorial parking garage, Museum of Science and Industry parking garage, Prudential Two, Water Tower. Idaho: Boise 11th Avenue Underpass. New York: World Trade Center Recovery, Goldman Sachs Project Phoenix, Con Edison sites. San Francisco, CA: Yerba Buena Tower Washington, DC: Petworth Subway Station, World Bank Bldg, Washington Convention Center. Tunneling: Atlantic Brigantine Cut and Cover Tunnel, NJ, No. 7 Line Extension, NY, Passageway expansion at No.7 line and Lexington Avenue intersection, Grove Street Station, NJ. Computer and Software Skills Plaxis Finite Element Software, Slope-W, GRL-WEAP pile drivability, RISA-2D and 3D - structural analysis, STAAD, AutoCAD, LPILE - lateral pile analysis for single piles, GROUP - lateral pile group analysis, Dynapile - dynamic pile analysis, PCA-Col, MS-Word, MS-Excel, Excellent user of PowerPoint, Primavera, Visual Basic 6, Visual Basic.Net (Software development), Developed Software: Deep Excavation Engineering Program D.E.E.P. Copyright 2001, Trench-1.0 for stability analysis of slurry filled trenches and panels Copyright 2003, Steel-Connect for design of steel connections Copyright 2003, Steel-Beam 1.0 for evaluation of steel beams under combined stress loading. Additional Educational Experience Technology and Policy Program, Sloan School of Management Courses: Managerial decision making, International management, Project Management. Associations American Society of Civil Engineers, Chi Epsilon - Civil Engineering Honor Society, Tau Beta Pi - Engineering Honor Society.

Job Responsibilities Project design, customer training, customer support, workshop instructor, programming, manuals - technical documentation,verification examples performance, marketing materials. Education 2004-2009: Aristotle University, Thessaloniki, Dipl. in Engineering, Civil Engineering (Structural) Work Experience 2009-2010: Military service, engineering July 2010 – present: Deep Excavation Llc, engineering 2012: Participation to the research program of Aristotle University of Thessaloniki, Greece - software development of a new concrete member design program. Representative Project & Design Experience - Braced excavation design for elevator shaft, MI: Design of deep excavation – supporting soldier pile walls - Braced excavation design for Los Angeles metro stations, CA: La Brea Station, Fairfax Station - Soil nailing wall design, Apple headquarters, CA: Design of soil nailing wall - Design of helical pile foundations for container home project, TX: Analyzed and designed the helical pile foundations - Design of helical pile foundations for Corocora electricity towers project, Colombia: Analyzed and designed a helical pile foundation system for supporting the electricity towers - Design of helical pile foundations in La Bocana, Colombia: Analyzed and designed the helical pile foundations - Design of helical pile foundations, OH: Analyzed and designed the helical pile foundations - Design of helical pile foundations for Florida Tanks project, FL: Analyzed and designed the helical pile foundations Software development projects: - Development assistance in the software program DeepXcav-DeepEX at Deep Excavation LLC. Programming, document preparation, technical support, marketing materials. - Co-development of the software program RCsolver, with Dimitrios Konstantakos (P.E. New York, Deep Excavation LLC) and Anastasios Sextos (PhD, assistant professor at A.U.TH.). Computer and Software Skills Professional user of Windows (98, XP, 7, 8, 10), Microsoft Office (Word, Excel, Power Point), AutoCAD, Fortran, Visual Basic 6, Visual Basic.NET (programming), ANSIS, SAP Nonlinear, RISA, DeepXcav- DeepEX, HelixPile, DeepFND, SnailPlus, RCsolver. PC Certification: Certified by Aristotle University of Thessaloniki. Publications - Diploma Thesis: “Software development for the design of concrete members according to Greek and European Standards” - ''Advantages and limitations of ultimate limit state design methods for braced excavations'', ASCE Conf. Proc. doi:10.1061/41128(384)82, Earth Retention Conference 3, Bellevue, Seattle, WA, August 1-4, 2010, secondary author.

Education 1997-2001 INTERNATIONAL UNIVERSITY OF FINANCE, bachelor with honors, 2001-2002 AMERICAN UNIVERSITY OF WASHINGTON, distance-learning course ''Implementation of computer technologies for international trade'', independent research ''International trade and environment'' 1999-2002 Japan center, Japanese language 2001-2002 National Aviation University, Master ''Accounting & Audit'', master degree with honors, master paper '' Accounting&Audit of foreign trade operations'' 2002-2005 Post graduate studies at the National Aviation University, research degree in ''Transport & Communication Economy'', ''Economical aspects of Air Traffic Management'' Working Experience 2008 — 2010 Deatrade Servic es , sales&marketing director, construction, real estate, specialized financial services 2005 – 2008 Computer World & Games , sales&business development director, development & sales of different software products worldwide 2004 – 2005 Information Technologies Center ITC , financial manager 2002 – 2004 Export-import company GITAS , marketing manager 2000 – 2002, State Tax Administration project manager of launch of automated tax software by the Government of the Netherlands 1998 – 2000 KM INFORM , marketing manager Hobbies Foreign languages, ancient history studies, communication, reading, golf, traveling

Education 2018: Aristotle University of Thessaloniki, Phd, Civil Engineering 2012: Aristotle University of Thessaloniki, Dipl. in Engineering, Civil Engineering Work experience 2016-Present: Lead software Engineer, Deep Excavation LLC, associated with the following projects: (a)Leading the development of the FEM Biot consolidation and FEM dynamic analysis module for the DeepEx software (b) Leading the development of the soil-foundation-bridge system analysis and design module of the software deepFND (c) Responsible for the development of a complete FEM engine (DeepFEM), performing inelastic FEM analysis (d) Responsible for the Development of an automated meshing module and a decision-making inference engine capable of automatically creating geotechnical FEM models in the software DeepEX. (e) Expansion of the DeepFND capabilities to the analysis and design of pile-group foundation systems. (f) Expansion of the Deepfnd software capabilities to the quasi static analysis of nonhelical piles through the development of inelastic concrete and timber pile modeling and design options. 2018: Research associate in the RSSB project T1073-2 “Development of a Methodology to Determine Loading Regimes for Track Designers”(investigation of dynamic load amplification on subsoil-track systems due to high speed railway) 2014-2015: Teaching Assistant, Aristotle University of Thessaloniki ("Programming techniques and use of advanced software for Structural Engineering” and “Applied Informatics for Civil Engineers”) 2014-2015: Research Associate - A.U.Th Research committee (research project 138609). 2013-2014: Research Associate -University of Toronto, (EXCHANGE-SSI-7th framework Marie Curie research project), Development of a robust substructuring methodology in the time domain with unconditionally stable behavior for soil-bridge dynamic systems. 2012-2013: Civil Engineer – ELKAT EPE , supervision duties on multiple projects on the construction and repair of Bucket wheel excavator moving equipment,participation in the redesign process of a steel footbridge due to settlement issues observed , tasks in the preparation of financial offers for project competitions. Associations Member of the American society of Civil Engineers ,Geo-Institute of ASCE, technical Chamber of Greece (T.E.E ), Hellenic Society of Earthquake Engineering reviewer at the following Scientific journals: Bulletin of Earthquake Engineering , Structures, International Journal of Sustainable Materials and Structural Systems Computer and Software Skills Programming in Python, C, C++, C#, Visual Basic, Matlab Expert knowledge of the following software suites: SAP2000, CSiBridge, OpenSees, Plaxis,AutoCAD, Microsoft Office Suite Publications Lesgidis, N., Kwon, O. and Sextos, A. (2015), A time-domain seismic SSI analysis method for inelastic bridge structures through the use of a frequency-dependent lumped parameter model. Earthquake Engineering and Structural Dynamics Lesgidis, N., Sextos, A. and Kwon, O. (2017), Influence of frequency-dependent soil–structure interaction on the fragility of R/C bridges. Earthquake Engineering and Structural Dynamics, Stefanidou S., Sextos A., Kotsoglou A., Lesgidis N., Kappos A. (2017), Soil-structure interaction effects in analysis of seismic fragility of bridges using an intensity-based ground motion selection procedure. Engineering Structures Lesgidis, N., Sextos, A. and Kwon, O. (2018), A frequency- and intensity-dependent macroelement for reduced order seismic analysis of soil-structure interacting systems, Earthquake Engineering and Structural Dynamics Lesgidis, N., Sextos. A, Moschen L., Gutierrez J., Pistone E. (2020), A rigorous modeling method for high speed railway through optimization-based model order reduction, Transportation Geotechnics Sextos, A., Lesgidis, N. (2013), Bridge-Wizard: Expert system for finite element modeling and post-processing of bridge structures. 4th ECCOMMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, Kos Island, Greece, 12-14 June 2013. Lesgidis, N., Sextos, A. and Kwon, O. (2015), Influence of the soil-foundation frequency-dependent behavior on the seismic performance of overpass bridges, Fifteenth International Conference on Civil, Structural and Environmental Engineering Computing Lesgidis, N., Sextos, A. and Kwon, O. (2017), Expansion of the lumped parameter method to nonlinear, soil-structure interacting dynamic systems by means of a multi-objective optimization algorithm, 6th ECCOMMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering Lesgidis, N., Sextos, A. and Kwon, O. (2018), A frequency and intensity dependent Lumped parameter model for considering SSI effects on seismic bridge design and assessment, Eleventh U.S. National Conference on Earthquake Engineering, Los Angeles, California Moschen L., Pichler D., Lesgidis N., Sextos, A. Lane,J. (2019), Which Load Model Do You Use for Rail Track Design? , Railway Engineering 2019, Edinburgh Lesgidis, N., Sextos, A. and Kwon, O. (2019), A reduced order approach for the simulation of vehicle induced ground-borne vibration, 7th ECCOMMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering Lesgidis, N., Sextos, A. and Moschen L. (2019), Model order reduction for holistic SSI modeling in earthquake and railway engineering applications, Engineering Mechanics Institute Conference 2019, Los Angeles, California