Cosmin G. Petra is a computer scientist in the Center for Applied Scientific Computing at Lawrence Livermore National Laboratory. Cosmin's work focuses on high-performance computing algorithms and C/C++ solvers for mathematical optimization with emphasis on applications in complex energy systems.

Prior to joining the Center for Applied Scientific Computing, Cosmin was with Argonne National Laboratory as a computational mathematician and, prior to that, hold software engineer/numerical analyst positions in IT industry. Cosmin obtained an M.S. and a Ph.D. in Applied Mathematics from the University of Maryland, Baltimore County, in 2006 and 2009, respectively.

- 2016-present -
*Computer Scientist/Computational Mathematician*, Center for Applied Scientific Computing, Lawrence Livermore National Laboratory. - 2015-2020 -
*Adjunct Asst. Professor*, School of Natural Sciencies, University of California, Merced. - 2012-2016 -
*Asst. Computational Mathematician*, MCS Division, Argonne National Laboratory. - 2009-2012 -
*Postdoctoral Appointee*, MCS Division, Argonne National Laboratory.

- 2006-2009 Ph.D. in Applied Mathematics - University of Maryland, Baltimore County, Baltimore, Maryland
- 2005-2006 M.S. in Applied Mathematics - University of Maryland, Baltimore County, Baltimore, Maryland
- 1998-2002 B.S. in Mathematics and Computer Science - Universitatea Babes-Bolyai, Cluj-Napoca, Romania

- First place in Division 1, 2, 3, and 4 of the ARPA-E GridOptimization Competition Challenge 1 (team/project name gollnlp) 2018-2020
- COAP 2013 Best Paper Prize
- DOE Incite Award 2012-2013, 24 million core hours
- 2013 COIN-OR INFORMS Cup
- Honorable mention - COAP 2011 Best Paper Prize

- Scalable algorithms for optimization, control, and design under uncertainty
- High-performance computing algorithms for mathematical optimization at extreme scale
- Scientific computing and extreme-scale computing
- Power grid optimization of real-world large-scale power systems

- Scalable algorithms for optimization, optimal control, and optimal design
- HPC optimization solver for continuous optimization - HiOp
- Optimization solvers for stochastic optimization - PIPS
- Optimization of power grid systems, mainly, solving real-world AC optimal power flows with contigency analysis

- J. J. Brust, S. Leyffer, C. G. Petra,
*Compact Representations of Structured BFGS Matrices,*SIAM Journal on Optimization, submitted, 2020. - J. J. Brust, R. F. Marcia, C. G. Petra,
*Computationally Efficient Decompositions of Oblique Projection Matrices,*SIAM Journal on Matrix Analysis and Applications, in review, 2020. - E. M. Constantinescu, N. Petra, J. Bessac, C. G. Petra,
*Statistical Treatment of Inverse Problems Constrained by Differential Equations-Based Models with Stochastic Terms,*accepted to SIAM Journal on Uncertainty Quantification, 2019. - C. G. Petra, M. Salazar De Troya, N. Petra, Y. Choi, G. M. Oxberry, and D. Tortorelli,
*A quasi-Newton interior-point method for optimization in Hilbert spaces*, submitted, 2019. - C. G. Petra, N. Chiang, M. Anitescu,
*A structured quasi-Newton algorithm for optimizing with incomplete Hessian information*, SIAM Journal on Optimization, Volume 29, Issue 2, 2019. DOI - J. J. Brust, R. F. Marcia, C. G. Petra,
*Large-scale quasi-Newton trust-region methods with low dimensional linear equality constraints*, Journal of Computational Optimization and Applications, Volume 74, Issue 3, 2019. DOI - K. Kim, C. G. Petra, V. M. Zavala,
*An asynchronous bundle-trust-region method for dual decomposition of stochastic mixed-integer programming*, SIAM Journal on Optimization, Volume 29, Issue 1, 2019. DOI - C. G. Petra, F. Potra,
*A Homogeneous Model for Monotone Mixed Horizontal Linear Complementarity Problems*, Journal of Computational Optimization and Applications, Volume 72, Issue 1, pages 241-267, 2019. DOI - V. Rao, K. Kim, M. Schanen, D. A. Maldonado, C. G. Petra, and M. Anitescu,
*A Multiperiod Optimization-Based Metric of Grid Resilience,*Proceedings of the 2019 IEEE PES General Meeting, 2019. - C. G. Petra,
*A memory-distributed quasi-Newton solver for nonlinear programming problems with a small number of general constraints*, Journal of Parallel and Distributed Computing, Volume 133, pages 337-348, 2019. DOI - M. Schanen, F. Gilbert, C. G. Petra, M. Anitescu,
*Towards multiperiod AC-based contingency constrained optimal power flow at large scale*, “Proceedings to the 20th Power Systems Computation Conference”, 2018. DOI - C. G. Petra, F. Qiang, M. Lubin, J. Huchette,
*On efficient Hessian computation using the edge pushing algorithm in Julia*, Optimization Methods and Software, Volume 33(4-6), pages 1010-1029, 2018. DOI - N. Petra, C. G. Petra, Z. Zhang, E. M. Constantinescu, and M. Anitescu,
*A Bayesian Approach for Parameter Estimation with Uncertainty for Dynamic Power Systems*, IEEE Transactions on Power Systems, Volume 32(4), pages 2735 - 2743, 2017. DOI. - C. G. Petra, V. M. Zavala, E. N. Ruiz, M. Anitescu,
*A high-performance computing framework for analyzing the economic impacts of wind correlation*, Electric Power Systems Research, Volume 141, pages 372-380, 2016. DOI. - J. Huchette, M. Lubin, C. G. Petra,
*Parallel algebraic modeling for stochastic optimization.*The First Workshop for High Performance Technical Computing in Dynamic Languages (HPTCDL), Supercomputing 2014. DOI. - C. G. Petra, O. Schenk, M. Anitescu.
*Real-time Stochastic Optimization of Complex Energy Systems on High Performance Computers.*Computing in Science & Engineering (CiSE) 16(5), pages 32-42. DOI. - N. Chiang, C. G. Petra, V. M. Zavala,
*Structured Nonconvex Optimization of Large-Scale Energy Systems Using PIPS-NLP.*18th IEEE Power Systems Computations Conference, 2014. - C. G. Petra, Olaf Schenk, Miles Lubin, Klaus Gaertner.
*An augmented incomplete factorization approach for computing the Schur complement in stochastic optimization.*SIAM J. Sci. Comput., 36-2, pages C139-C162, 2014. DOI - M. Lubin, K. Martin, C.G. Petra, and Burhaneddin Sandikic.
*On parallelizing dual decomposition in stochastic integer programming.*Operations Research Letters 41(3), pages 252-258, 2013. DOI - M. Lubin, C. G. Petra, M. Anitescu, and V. Zavala.
*Scalable Stochastic Optimization of Complex Energy Systems.*In Proceedings of 2011 International Conference for High Performance Computing, Networking, Storage and Analysis (SC '11), pages 64:1-64:10. DOI - M. Lubin, J. A. J. Hall, C. G. Petra, and M. Anitescu.
*Parallel distributed-memory simplex for large-scale stochastic LP problems.*, Computational Optimization and Applications 55(3), pages 571-596, 2013.**Coin-OR INFORMS 2013 Cup winner**+**2013 COAP Best Paper.**DOI - M. Lubin, C. G. Petra, M. Anitescu.
*On the parallel solution of dense saddle-point linear systems arising in stochastic programming.*Optimization Methods and Software, Volume 27, Number 4-5, Pages 845-864, 2012. - C. G. Petra, M. Anitescu.
*A preconditioning technique for Schur complement systems arising in stochastic optimization.*Computational Optimization and Applications, Pages 315-344, Volume 52, Issue 2, 2012. - A. Draganescu, C. G. Petra.
*Multigrid preconditioning of linear systems for interior point methods applied to a class of bound-constrained control problems.*SIAM Journal on Numerical Analysis, Volume 50, Number 1, Pages 328-353, 2012. - S. Al-Homidan, M. M. Alshahrani, C. G. Petra, F. A. Potra.
*Minimal Condition Number for Positive Definite Hankel Matrices using Semidefinite Programming.*Linear Algebra and Its Applications, Volume 433, Issue 6, Pages 1101-1109, November 2010. - F. Gurtuna, C. G. Petra, F. A. Potra, O. Schevchenko, A. Vancea.
*Corrector-Predictor Methods for sufficient linear complementarity problems.*Computational Optimization and Applications, Volume 48, Issue 3, Pages 453-485, April 2011.**COAP Best Paper 2011 - Honorable mention.** - C. G. Petra, B. Gavrea, M. Anitescu, F. A. Potra.
*A computational study on the use of an optimization based method in the simulation of large multi-body systems*. Optimization Methods and Software, Volume 24, Issue 6, Pages 871-894, 2009.

- C. G. Petra, "
*HiOp - User manual",*Tech Report LLNL-SM-743591, 2018, Lawrence Livermore National Laboratory. - M. Anitescu, C. G. Petra.
*Higher-Order Confidence Intervals for Stochastic Programming using Bootstrapping,*2012, Tech Report ANL/MCS-P1964-1011. Argonne National Laboratory. - R. Serban, C. G. Petra.
*User Documentation for IDAS v1.0.0*, 2008, Report UCRL-SM-234051, Lawrence Livermore National Laboratory.

*SC-ACOPF using nonlinear non-convex optimization and high-performance computing,*INFORMS Annual Meeting (2019), ARPA-E GridOptimization Outreach Event (2020)*Parallel Structured Quasi-Newton Methods for Material Design*, SIAM Conference on Optimization (2017), SIAM Student Chapter, UC Davis (2017)*Optimization and Design of Complex Engineering Systems using High-Performance Computing*, SIAM-CSE (2017).*Scalable stochastic optimization of complex energy systems on high-performance computers*, Zuse Institut Berlin (2016)*Modelling and solving SC-ACOPF problems in parallel*, FERC Technical Conference on Increasing Market and Planning Efficiency through Improved Software (2016)*Optimization-based parameter estimation of dynamic power grid systems*, SIAM UQ (2016).*Scalable optimization of complex energy systems using high-performance computing*, Joint Mathematics Meeting, SIAM Parallel Processing (2016)*Parallel algebraic modelling for stochastic optimization in Julia*, Platform for Advanced Scientific Computing Conference (2015)*On the role of wind correlation in the economic dispatch of power grid systems*, SIAM CSE (2015)

This document is released under LLNL IM Release Number LLNL-WEB-403310.