## Publications

### Journal Publications

- M. Krishnan,
**S. Gugercin,**and P. Tarazaga.*“A wavelet-based dynamic mode decomposition for modeling mechanical systems from partial observations*“, Submitted, 2021. Available as arXiv:2110.12990. - E. Qian, J. Tabeart, C. Beattie,
**S. Gugercin**. J. Jiang, P. Kramer, and A. Narayan.*“Model reduction of linear dynamical systems via balancing for Bayesian inference*“, 2021. Available as arXiv:2111.13246. - I. V. Gosea,
**S. Gugercin,**and C. Beattie.*“Data-driven balancing of linear dynamical systems*“, 2021. Accepted to appear in SIAM Journal on Scientific Computing. Available as arXiv:2104.01006. - I. V. Gosea and
**S. Gugercin**.*“Data-driven modeling of linear dynamical systems with quadratic output in the AAA framework*“, 2021. Available as arXiv:2102.13487. - M. Brennan, M. Embree, and
**S. Gugercin.**“*Contour integral methods for nonlinear eigenvalue problems: A systems theoretic approach”,*2020. Available as arXiv:2012.14979. - V.V.N.S. Malladi, M.I. Albakri, M, Krishnan,
**S. Gugercin**, P.A. Tarazaga. “*Estimating Experimental Dispersion Curves from Steady-State Frequency Response Measurements*“, Mechanical Systems and Signal Processing, Vol. 164, 108218, 2021.. Available as arXiv:2101.00155. - A. Carr, E. de Sturler, and
**S. Gugercin.**“Preconditioning parametrized linear systems”. SIAM Journal on Scientific Computing, Vol. 43, No. 3, pp. A2242–A2267, 2021. Available as arXiv:1601.05883. - S. Reiter, M. Embree, and
**S. Gugercin.**“*The balanced truncation bound is tight for SISO systems when the truncated system is state-space symmetric”,*2020. Available as arXiv:2011.07170. - P. Benner,
**S. Gugercin,**and S. Werner. “*Structure-preserving interpolation for model reduction of parametric bilinear systems*“. Automatica, Vol. 132, 109799, 2021. Available as arXiv:2007.11269 - B. Peherstorfer, Z. Drmac, and
**S. Gugercin**. “*Stability of discrete empirical interpolation**and gappy proper orthogonal decomposition with randomized and**deterministic sampling points*“. SIAM Journal on Scientific Computing, Vol. 42, No. 5, pp. A2837–A2864, 2020. - A. Carracedo Rodriguez and
**S. Gugercin**. “*The p-AAA algorithm for data driven modeling of parametric dynamical systems*“. Submitted, 2020. Available as arXiv:2003.06536 - S. Aslan, E. de Sturler, and
**S. Gugercin.**“*Randomization for the efficient computation of parametric reduced order models for inversion*“. 2020. Available as arXiv:2007.06027 - P. Benner,
**S. Gugercin,**and S. Werner. “*Structure-preserving interpolation of bilinear control systems.*” Accepted to appear in Advances in Computational Mathematics**47**, 43, 2021. Available as arXiv:2005.00795 - C.A. Beattie, Z. Drmac, and
**S. Gugercin**. “*Revisiting IRKA: Connections with pole placement and backward stability.*” Vietnam Journal of Mathematics, Vol. 48, pp. 963–985, 2020. Earlier draft version available as arXiv:1911.05804. - C.A. Beattie,
**S. Gugercin,**and V. Mehrmann. “*Structure-preserving Interpolatory Model Reduction for Port-Hamiltonian Differential-Algebraic Systems.*” Accepted to appear, 2020. Available as arXiv:1910.05674 - T. Breiten, C. Beattie, and
**S. Gugercin**. “*H2-gap model reduction for stabilizable and detectable systems.*” Accepted to appear, 2020. Available as arXiv:1909.13764 - C.A. Beattie,
**S. Gugercin**, and Z. Tomljanovic. “*Sampling-free parametric model reduction for structured systems.*“. Advances in Computational Mathematics, 46:83, 2020. View-only Sharedit Version. Earlier version as arXiv:1912.11382 - M.I. Albakri, V.V.N.S. Malladi,
**S. Gugercin**, P.A. Tarazaga. “*Estimating Dispersion Curves from Frequency Response Functions via Vector-Fitting.*” Mechanical Systems and Signal Processing, Vol. 140, 106597, 2020. - K. Sinani and
**S. Gugercin**. “*H_2(t_f) Optimality Conditions for a Finite-time Horizon*“. Automatica, Vol. 110, 2019. - B. Unger and
**S. Gugercin**. “*Kolmogorov n-widths for linear dynamical systems*“. Advances in Computational Mathematics, Vol. 45, pp. 2273–2286, 2019. - A. Grimm, C.A. Beattie, Z Drmac, and
**S. Gugercin**. “*Empirical least-squares fitting of parametrized dynamical systems*“. Submitted 2018. Available as arXiv:1808.05716. - P. Benner,
**S. Gugercin**, and K. Willcox. “*A Survey of Projection-Based Model Reduction Methods for Parametric Dynamical Systems.*” SIAM Review, Vol. 57, Issue: 4, pp. 483—531, 2015. - B. Peherstorfer,
**S. Gugercin**, and K. Willcox. “*Data-driven Reduced Model Construction with Time-domain Loewner Models.*” SIAM Journal on Scientific Computing, Vol. 39, Issue 5, pp. A2152—A2178, 2017. - V. Malladi, M. Albakri,
**S. Gugercin,**P. Tarazaga. “*Application of projection-based model reduction to finite-element plate models for two-dimensional traveling waves*.” Journal of Intelligent Material Systems and Structures, Vol 28, Issue 14, pp. 1886—1904, 2017 . - A. Carracedo Rodriguez,
**S. Gugercin**, and J. Borggaard. “*Interpolatory Model Reduction of Parameterized Bilinear Dynamical Systems*“. Advances in Computational Mathematics, pp. 1—30, 2018. - Z. Tomljanovic, C.A. Beattie, and
**S. Gugercin**. “*Damping optimization of parameter dependent mechanical systems by rational interpolation*“. Advances in Computational Mathematics, pp. 1—24, 2018. - P. Schulze, B. Unger, C. Beattie, and
**S Gugercin**.”*Data-driven Structured Realization*“. Linear Algebra and Its Applications, Volume 537, Issue 15, pp. 250—286, 2018. - P. Benner, P. Goyal, and
**S. Gugercin**. “*H*” SIAM Journal on Matrix Analysis and Applications, Vol. 39 No. 2, pp. 983—1032, 2018._{2}-Quasi-Optimal Model Order Reduction for Quadratic-Bilinear Control Systems. - C. Beattie,
**S. Gugercin**and V. Mehrmann. “ - M. O’Connell, M. Kilmer, E. de Sturler, and S. Gugercin. “Computing Reduced Order Models via Inner-Outer Krylov Recycling in Diffuse Optical Tomography”. SIAM Journal on Scientific Computing, Vol. 39, No. 2, pp. B272—B297, 2017.
- C. Magruder, C. Beattie,
**S. Gugercin.**“*Linear time-periodic dynamical systems: An H2 analysis and a model reduction framework.*” Mathematical and Computer Modelling of Dynamical Systems, pp. 1—24, 2017. - S. Chaturantabut, C. Beattie, and
**S. Gugercin**. “*Structure-preserving Model Reduction for Nonlinear Port-Hamiltonian Systems*“. SIAM Journal on Scientific Computing, Vol. 38, No. 5, pp. B837—B865, 2016. - Z. Drmac and
**S. Gugercin**. “*A New Selection Operator for the Discrete Empirical Interpolation Method — improved a priori error bound and extensions.*” SIAM Journal on Scientific Computing, Vol. 38, No. 2, pp. A631—A648, 2016. - B. Kramer and
**S. Gugercin**. ” The Eigensystem Realization Algorithm from Tangentially Interpolated Data”. Mathematical and Computer Modelling of Dynamical Systems, Vol. 22, Issue. 4, pp. 282—306, 2016. - Z. Drmac,
**S. Gugercin**and C.A. Beattie. “*Vector Fitting for Matrix-valued Rational Approximation.*” SIAM Journal on Scientific Computing, Vol. 37, Issue: 5, pp. A2151—S626, 2015. - Z. Drmac,
**S. Gugercin**and C.A. Beattie. “*Quadrature-Based Vector Fitting For Discretized H*” SIAM Journal on Scientific Computing, Vol. 37, Issue: 2, A625—A652, 2015._{2}Approximation. - G. Flagg and
**S. Gugercin**. “*Multipoint Volterra Series Interpolation and H*” SIAM Journal on Matrix Analysis and Applications, Vol. 36, Issue: 2, 549—579, 2015._{2}Optimal Model Reduction of Bilinear Systems. - E. de Sturler,
**S. Gugercin**, M. E. Kilmer, S. Chaturantabut, C. Beattie, and M. O’Connell. “*Nonlinear Parametric Inversion using Interpolatory Model Reduction.*” SIAM Journal on Scientific Computing, Vol. 37, Issue: 3, B495—B517, 2015. - T. Breiten, C. Beattie, and
**S. Gugercin**. “*Near-optimal Frequency-weighted Interpolatory Model Reduction.*” Systems and Control Letters. Vol. 78, pp. 8—18. **S. Gugercin**, T. Stykel, and S. Wyatt. “*Model Reduction of Descriptor Systems by Interpolatory Projections Methods.”*SIAM Journal on Scientific Computing, Vol. 35, Iss. 5, pp. B1010—B1033, 2013.- G. Flagg and
**S. Gugercin**. “*On the ADI method for the Sylvester Equation and the optimal-H*Applied Numerical Mathematics, Vol. 64, pp. 50—58, 2013._{2}points.” - B. Anic, C.A. Beattie,
**S. Gugercin**and A.C. Antoulas.*“Interpolatory Weighted-H*.” Automatica, Vol. 49, Iss. 5, pp. 1275—1280, 2013._{2}Model Reduction - G. Flagg, C.A. Beattie and
**S. Gugercin**,*“Convergence of the Iterative Rational Krylov Algorithm*“, Systems and Control Letters, Volume: 61, Issue: 6, pp. 688—691, 2012. - G. Flagg, C.A. Beattie and
**S. Gugercin**. “*Interpolatory H-infinity Model Reduction*,” Systems and Control Letters, Vol. 62, Iss. 7, pp. 567—574, 2013. - K. Ahuja, E. de Sturler, R. Chang and
**S. Gugercin**, ”*Recycling BiCG with an Application to Model Reduction”*, SIAM Journal on Scientific Computing, Vol. 34, Issue: 4, pp. A1925—A949, 2012. **S. Gugercin**, R. V. Polyuga, C.A. Beattie and A. van der Schaft,*“Structure-preserving tangential-interpolation based model reduction of port-Hamiltonian Systems*.” Automatica, Vol. 48, Issue: 9, pp. 1963—1974, 2012.- C.A. Beattie,
**S. Gugercin**, and S. Wyatt,*“Inexact Solves in Interpolatory Model Reduction”.*Linear Algebra and its Applications, Vol. 436, Issue: 8, pp. 2916—2943, 2012. - C.A. Beattie, Z. Drmac, and
**S. Gugercin**,*A note on shifted Hessenberg systems and frequency response computation,*ACM Transaction on Mathematical Software, Vol 38, No. 2, 2011. - U. Baur, C.A. Beattie, P. Benner and
**S. Gugercin**,*“Interpolatory Projection Methods for Parameterized Model Reduction”*. SIAM Journal on Scientific Computing, Vol. 33, Issue: 5, pp. 2489—2518, 2011. - C.A. Beattie and
**S. Gugercin**,*“Interpolatory Projection Methods for Structure-preserving Model Reduction”.*Systems and Control Letters, Vol. 58, Issue: 3, pp: 225—232, 2009. **S. Gugercin**, A.C. Antoulas and C.A. Beattie,*“H*SIAM Journal on Matrix Analysis and Applications Vol. 30, Issue: 2, pp. 609—638, (2008)._{2}model reduction for large-scale linear dynamical systems”.**S. Gugercin**, “*An iterative SVD-Krylov based algorithm for model reduction of large-scale dynamical systems*“, Linear Algebra and its Applications Vol. 428 No: 8—9 pp. 1964-1986 (2008).**S. Gugercin**and K. Willcox,*“Krylov projection framework for Fourier model reduction*“, Automatica Vol. 44 No:1 pp. 209—215 (2008) .**S. Gugercin**and A.C. Antoulas. “*Model reduction of large-scale systems by least squares*“, Linear Algebra and its Applications, Special Issue on Order Reduction of Large-Scale Systems, Vol. Vol: 415 No:2-3, pp. 290—321 (2006).**S. Gugercin**and A.C. Antoulas.*A survey of model reduction by balanced truncation and some new results.*International Journal of Control, Vol: 77 No: 8, pp. 748—766 (2004) (Copyright Taylor & Francis, 2004)**S. Gugercin**, A.C. Antoulas, and H.P. Zhang. “*An approach to identification for robust control*“, IEEE Transactions on Automatic Control, Vol. 48 No: 6 pp. 1109—1115 (2003).**S. Gugercin**, D.C. Sorensen, and A.C. Antoulas. “*A modified low-rank Smith method for large-scale Lyapunov Equations*“, Numerical Algorithms, Vol. 32, No: 1, pp. 27—55, (2003)- A.C. Antoulas, D.C. Sorensen, and
**S. Gugercin**.*A survey of model reduction methods for large-scale systems*. Structured Matrices in Operator Theory, Numerical Analysis, Control, Signal and Image Processing, Contemporary Mathematics, AMS publications, 280: 193—219, 2001. (Copyright AMS, 2001)

### Books / Book Chapters

- A.C. Antoulas, C.A. Beattie, and
**S. Gugercin**.*Interpolatory Methods for Model Reduction.*Computational Science and Engineering 21, SIAM, Philadelphia, 2020. - A. Castagnotto, C.A. Beattie, and
**S. Gugercin**.*Interpolatory methods for H∞ model reduction of multi-input/multi-output systems.*In: Benner P., Ohlberger M., Patera A., Rozza G., Urban K. (eds) Model Reduction of Parametrized Systems. MS&A (Modeling, Simulation and Applications), vol 17, pp. 349—365, Springer, Cham, 2017. - J.T. Borggaard and
**S. Gugercin**. Model Reduction for DAEs with an Application to Flow Control. Active Flow and Combustion Control 2014, R. King editors, Springer-Verlag, Notes on Numerical Fluid Mechanics and Multidisciplinary Design, Vol. 127, (ISBN 978-3-319-11966-3), pp. 381—396, 2015. - C.A. Beattie and
**S. Gugercin**. Model Reduction by Rational Interpolation. In P. Benner, A. Cohen, M. Ohlberger, and K. Willcox (eds.), Model Reduction and Approximation: Theory and Algorithms, pp. 297—334, SIAM, Philadelphia, PA, 2017. - A.C. Antoulas, C.A. Beattie and
**S. Gugercin**. Interpolatory model reduction of large-scale dynamical systems.*Efficient Modeling and Control of Large-Scale Systems,*J. Mohammadpour and K. Grigoriadis editors, Springer-Verlag, ISBN 978-1-4419-5756-6, Publication date: Feb. 2010. (Copyright Springer, 2009) **S. Gugercin**and J.-R. Li. Smith-type methods for balanced truncation of large-sparse systems.*Dimension Reduction of Large-scale Systems,*P. Benner, G.H. Golub, V.L. Mehrman and D.C. Sorensen editors, Springer-Verlag, Lecture Notes in Computational Science and Engineering, Vol. 45 (ISBN 3-540-24545-6), Berlin/Heidelberg, 2005. (Copyright Springer, 2005)

### Refereed Conference Proceedings

- S. W. R. Werner, I. V. Gosea,
**S. Gugercin,**and B. Unger.*“Structured vector fitting framework for mechanical systems.*” Submitted, 2021. Available as arXiv:2110.09220 - I. V. Gosea,
**S. Gugercin,**and B. Unger.*“Parametric model reduction via rational interpolation along parameters.*” Accepted to appear in IEEE Conference on Decision and Control, 2021. Available as arXiv:2104.01016. - B. Safaee and
**S. Gugercin**.*“Data-driven modeling of power networks.*” Accepted to appear in IEEE Conference on Decision an Control, 2021. Available as arXiv:2104.06478. - B. Safaee and
**S. Gugercin.**“Structure-preserving model reduction of parametric power networks.” Accepted to appear in the Proceedings of the 2021 American Control Conference Submitted, 2021. Available as arXiv:2102.05179. - I. V. Gosea and
**S. Gugercin**. “The AAA Framework for Modeling Linear Dynamical Systems with Quadratic Output.” Extended Abstract, 21st IFAC World Congress (IFAC 2020). Available as arXiv:2005.10316. - K. Sinani,
**S. Gugercin**, and C. Beattie. ” A Structure-preserving Model Reduction Algorithm for Dynamical Systems with Nonlinear Frequency Dependence” . Proceedings of the 6th IFAC Symposium on System Structure and Control SSSC 2016. Available as IFAC-PapersOnLine, Volume 49, Issue 9, 2016, Pages 56-61. - I. Pontes Duff,
**S. Gugercin**, C. Beattie, C. Poussot-Vassal, C. Seren. “H_{2}-optimality conditions for reduced time-delay systems of dimension one”. Proceedings of the 13th IFAC Workshop on Time Delay Systems TDS, 2016. Available as IFAC-PapersOnLine Volume 49, Issue 10, 2016, Pages 7–12. - J. Borggaard, S. Gugercin, and Lizette Zietsman. Feedback Stabilization of Fluids Using Interpolatory and POD Reduced-Order Models for Control and Compensator Design Accepted to appear in Proceedings of the 55th IEEE Conference on Decision and Control, 2016.
- C.A. Beattie, Z. Drmac,
**S. Gugercin**. “Quadrature-Based IRKA Fitting for optimal H2 approximation.”Proceedings of 8th Vienna International Conferenceon Mathematical Modelling – MATHMOD 2015, available as IFAC-PapersOnLine, Volume 48, Issue 1, Pages 5-6, 2015. - J. Borggaard,
**S. Gugercin**, and L. Zietsman. “Compensators via H2-based Model Reduction and Proper Orthogonal Decomposition” Proceedings of 19th IFAC World Congress, 2014. - C.A. Beattie, and
**S. Gugercin**. Realization-independent H2-approximation.*Proceedings of the 51st IEEE Conference on Decision and Control*, Maui, HI, USA, December 2012. (Copyright IEEE, 2012) - D. Kim, J. Braun, J. Borggaard, E. Cliff,
**S. Gugercin**. Coupled CFD/Building Envelope Model for the Purdue Living Lab.*Proceeding of the 2012 High Performance Buildings Conference at Purdue*, West Lafayette, IN, USA, July 2012. - J. Borggaard, E. Cliff and
**S. Gugercin**. Model reduction for indoor-air behavior in control design for energy-efficient Buildings.*Proceedings of the 2012 American Control Conference*, Montreal, Canada, June 2012. - C.A. Beattie, and
**S. Gugercin**. Structure-preserving model reduction of nonlinear port-Hamiltonian systems.*Proceedings of the 50th IEEE Conference on Decision and Control*, pp. 6564-6569, Orlando, FA, USA, 2011. - C.A. Beattie and
**S. Gugercin**. Weighted model reduction via interpolation.*Proceedings of the 18th IFAC World Congress*, pp. 12757-12760, Milano, Italy, August 28- September 2, 2011. - C. Magruder, C.A. Beattie, and
**S. Gugercin**. Rational Krylov methods for optimal L2 model reduction.*Proceedings of the 49th IEEE Conference on Decision and Control*, pp. 6797-6802, Atlanta, GA, USA, December 2010. (Copyright IEEE, 2010) - G. Flagg, S. Gugercin and C.A. Beattie. An interpolation-based approach to H∞ model reduction of dynamical systems.
*Proceedings of the 49th IEEE Conference on Decision and Control*, pp. 6791-6796, Atlanta, GA, USA, December 2010. (Copyright IEEE, 2010) - C.A. Beattie and
**S. Gugercin**. A trust region method for optimal H2 model reduction.*Proceedings of the Joint 48th IEEE Conference on Decision and Control, and 28th Chinese Control Conference*, pp. 5370-5375, Shanghai, P.R. China, December 2009. (Copyright IEEE, 2009) **S. Gugercin**, R. Polyuga, C.A. Beattie and, A. van der Schaft. Interpolation-based H2 model reduction for port-Hamiltonian systems.*Proceedings of the Joint 48th IEEE Conference on Decision and Control, and 28th Chinese Control Conference*, pp. 5362-5369, Shanghai, P.R. China, December 2009. (Copyright IEEE, 2009)- C.A. Beattie and
**S. Gugercin**. Interpolation theory for structure-preserving model reduction.*Proceedings of the 47th IEEE Conference on Decision and Control*, pp. 4204-4208, Cancun, Mexico, December 2008. (Copyright IEEE, 2008) - C.A. Beattie and
**S. Gugercin**. Krylov-based minimization for optimal*H*2*model reduction.**Proceedings of the 46th IEEE Conference on Decision and Control,*2007. (Copyright IEEE, 2007) **S. Gugercin**, A. C. Antoulas and Christopher A. Beattie. A rational Krylov Iteration for Optimal*H*2 Model Reduction.*Proceedings of the 17th International Symposium on Mathematical Theory of Networks and Systems*, pp. 1665-1667, July 2006.- C.A. Beattie and
**S. Gugercin**. Inexact solves in Krylov-based model reduction.*Proceedings of the 45th IEEE Conference on Decision and Control,*pp. 3405-3411, December 2006. (Copyright IEEE, 2006) - C.A. Beattie, J. Borggaard,
**S. Gugercin**and T. Iliescu. A domain decomposition approach to POD.*Proceedings of the 45th IEEE Conference on Decision and Control,*pp. 6750-6756, December 2006. (Copyright IEEE, 2006) - C.A. Beattie and
**S. Gugercin**. Krylov-based model reduction of second-order systems with proportional damping.*Proceedings of the 44th IEEE Conference on Decision and Control,*pp. 2278-2283, December 2005. (Copyright IEEE, 2005) **S. Gugercin**. An iterative SVD-Krylov based method for model reduction of large-scale dynamical systems.*Proceedings of the 44th IEEE Conference on Decision and Control*, pp. 5905-5910, December 2005. (Copyright IEEE, 2005)**S. Gugercin**, A.C. Antoulas, C.A. Beattie, and E. Gildin. Krylov-based controller reduction for large-scale systems.*Proceedings of the 43rd**IEEE Conference on Decision and Control*, Vol. 3, pp. 3074-3077, December 2004. (Copyright IEEE, 2004)- C.A. Beattie,
**S. Gugercin**, A.C. Antoulas and E. Gildin. Controller reduction by Krylov projection methods.*Proceedings of the 16th International Symposium on Mathematical Theory of Networks and Systems*, July 2004. **S. Gugercin**and A.C. Antoulas. An*H*2 error expression for the Lanczos procedure.*Proceedings of**the 42nd IEEE Conference on Decision and Control*, Vol. 2, 1869-1872, December 2003. (Copyright IEEE, 2003)**S. Gugercin**and A.C. Antoulas. A time-limited balanced reduction method.*Proceeding*s of*the 42nd IEEE Conference on Decision and Control*, Vol. 5, pp. 5250-5253, December 2003. (Copyright IEEE, 2003)**S. Gugercin**and A.C. Antoulas. A survey of balancing methods for model reduction.*Proceedings of European Control Conference 2003,*Cambridge, UK,September 2003.- A.C. Antoulas and
**S. Gugercin**. A new approach to model reduction which preserves stability and passivity.*Proceedings of the 41st IEEE Conference on Decision and Control*, Vol. 3, pp. 2544-2545, Las Vegas, Nevada, December 2002. (Copyright IEEE, 2002) **S. Gugercin**, A.C. Antoulas, N. Bedrossian. Approximation of International Space Station 1R and 12A Models.*Proceedings of the 40th IEEE Conference on Decision and Control*, Vol. 3, pp. 1515-1516, Orlando, Florida, December 2001. (Copyright IEEE, 2001)**S. Gugercin**and A.C. Antoulas. A comparative study of 7 algorithms for model reduction.*Proceedings of the 39th IEEE Conference on Decision and Control*, Vol. 3, pp. 2367-2372, Sydney, Australia, December 2000. (Copyright IEEE, 2000)**S. Gugercin**and A.C. Antoulas. On consistency and model validation for systems with parameter uncertainty.*Proceedings of SYSID2000*, Santa Barbara, California, June 2000. (Copyright IFAC, 2000)**S. Gugercin**and A.C. Antoulas. On the assignment of eigenvalues in LTI systems.*Proceedings of the 38th IEEE Conference on Decision and Control*, Vol. 1, pp. 486, Phoenix, Arizona, December 1999. (Copyright IEEE, 1999)