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CE Home > People > Faculty Directory > Steven F. Wojtkiewicz
Steven F. Wojtkiewicz
Assistant Professor
Contact Information:
- Office: CivE 240
- Phone: (612)624-0063
- Fax: (612)626-7750
- E-mail: ykvich@umn.edu
Research Interests:
The ultimate goal of computational science and engineering is to provide model-based predictions that serve as surrogates for physical tests. In order to achieve this goal, one must have a measure of the model's predictive content, i.e., its validity. While the estimation of errors associated with the discretization of the partial differential equations governing a particular problem is a very active research field, the interpretation and estimation of errors associated with natural variability and limited data is, on the other hand, an emerging field. The uncertainty quantification field addresses these issues and is essential in the validation process. The core theme of my research is the modeling of uncertainty in computational science and engineering and its subsequent use in the analysis, design, control, and optimization of complex engineering systems.
Areas of recent research include:
- Stochastic modeling in the physical and natural sciences
- Computational mechanics and optimization
- Dynamics, control, and optimization of structural systems
- Vulnerability analysis of structural systems
Selected Publications:
M.S. Eldred, H.Agarwal, V.M. Perez, S.F. Wojtkiewicz, and J.E. Renaud. Investigation of Reliability Methods in DAKOTA/UQ. Structure and Infrastructure Engineering: Maintenance, Management, Life-Cycle Design and Performance, in press.
W.L. Oberkampf, J.C. Helton, C.A. Joslyn, S.F. Wojtkiewicz, and S. Ferson. 2004. Uncertainty in system response given uncertain parameters. Reliability Engineering and System Safety. 85(1-3): 11-19.
S.F. Wojtkiewicz and L. A. Bergman. 2001. A moment specification algorithm for control of nonlinear systems driven by Gaussian white noise. Nonlinear Dynamics, 24(1): 17-30.
S.F. Wojtkiewicz, M.S. Eldred, R.V. Field, Jr., A. Urbina, and J.R. Red-Horse. 2001. A toolkit for uncertainty quantification in large computational engineering models. In Proceedings of the 42nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Seattle, Wash., April 16-19.
S.F. Wojtkiewicz, E.A. Johnson, L.A. Bergman, M. Grigoriu, and B.F. Spencer, Jr. 1999. Response of stochastic dynamical systems driven by additive Gaussian and Poisson white noises: Numerical solution of the forward Kolmogorov-Feller equation. Computer Methods in Applied Mechanics and Engineering, 168(1-4): 73-89.
L.A. Bergman, B.F. Spencer, Jr., and S.F. Wojtkiewicz. 1997. A state-of-the-art report on computational stochastic mechanics. Probabilistic Engineering Mechanics, 12(4): 197-321.
E.A. Johnson, S.F. Wojtkiewicz, L.A. Bergman, and B.F. Spencer Jr. 1997. Observations with regard to massively parallel computation for Monte Carlo simulation of stochastic dynamical systems. International Journal of Non-linear Mechanics, 32(4): 721-734.
L.A. Bergman, B.F. Spencer Jr., S.F. Wojtkiewicz and E.A. Johnson. 1996. Robust numerical solution of the Fokker-Planck equation for second order dynamical systems under parametric and external white noise excitations. Fields Institute Communications, Nonlinear Dynamics and Stochastic Mechanics: 23-37.
S.F. Wojtkiewicz, B.F. Spencer, Jr., and L.A. Bergman. 1996. On the cumulant-neglect closure method in stochastic dynamics. International Journal of Non-linear Mechanics, 31(3): 657-684.
Education:
- Ph.D., 2000, Aeronautical and Astronautical Engineering/Computational Science and Engineering, University of Illinois at Urbana-Champaign
- M.S., 1994, Aeronautical and Astronautical Engineering, University of Illinois at Urbana- Champaign
- B.S. (Honors), 1993, University of Illinois at Urbana-Champaign
Experience:
- Research assistant professor, Department of Aerospace and Mechanical Engineering, University of Southern California, 2005
- Postdoctoral fellow, Department of Civil Engineering, Johns Hopkins University, 2004
- Senior technical staff, Structural Dynamics Research and Smart Systems Department, Sandia National Laboratories, 1999-2004
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