Tudor-Corneliu IonescuProfessor Habil.
areas of expertise
- Systems Theory and Automatic Control
- Modeling
- Dynamic Systems
education
- PhD: Applied Mathematics, University of Groningen, The Netherlands, 2009
- Master: Systems Engineering and Automatic Control, University Politehnica of Bucharest, Romania, 2004
Dr. Tudor C. Ionescu was born in Bucharest, Romania, in 1980. He holds a master’s degree in Systems Engineering and Automatic Control from the University Politehnica of Bucharest (2004) and a PhD in Applied Mathematics from the University of Groningen, The Netherlands (2009). During his PhD, he conducted research visits at Supelec, Paris, France (2005 and 2007), and at Nagoya University, Japan (2008). He has served as an Associate Researcher at Imperial College London, UK (2009-2013), and at the University of Sheffield, UK (2013-2015). He was awarded the Dutch Science Foundation (NWO) Visitor’s Grant at the University of Groningen (2011 and 2015). Currently, Dr. Ionescu is an Associate Professor at the Department of Automatic Control and Systems Engineering, University Politehnica of Bucharest. He is also a part-time Senior Researcher at the “Gheorghe Mihoc – Caius Iacob” Institute of Mathematical Statistics and Applied Mathematics of the Romanian Academy, Bucharest. His research interests include nonlinear systems modeling and control, with a focus on model reduction techniques while preserving the physical structure and finite-dimensional approximation of systems with time delays or distributed parameters.
“The essence of science is independent thinking and a constant quest for understanding the unknown.”
Qualifications
• PhD in Applied Mathematics
• January 2005–September 2009. Awarded by the University of Groningen NL.
• Title of the thesis: Balanced Truncation for Dissipative and Symmetric Nonlinear Systems
• I have developed model approximation algorithms for nonlinear complex physical sys- tems based on nonlinear balanced truncation. The reduced order models obtained through these procedures preserve crucial properties of the complex model, required for analysis, simulation and control design.
• The results have been disseminated in two peer-reviewed journal papers, four peer- reviewed conference papers and two refereed book chapters.
• BSc. and MSc. in Systems and Control
• October 1999–June 2004 at the Politehnica University of Bucharest, Romania.
• Title of the MSc. thesis: Stability Analysis of Neutral Systems: a Delay- dependent Criterion
• Grade: 10 out of 10.
• I have analysed the application of LMI techniques for establishing delay-dependent stability criteria for neutral time-delay systems. I have obtained computational algo- rithms which determined the largest value of the delay for which the neutral system remains asymptotically stable.
• The results have been disseminated in two peer-reviewed conference papers.
Grants and awards
• ScaleFreeNet Exploratory Research National Grant
• September 2017 – present. ”Scale-free modeling and optimization techniques for control of complex networks” (ScaleFreeNet) exploratory research project, funded through the Romanian Executive Agency for Higher Education, Research, Develop- ment and Innovation Funding (UEFISCDI) grant PN-III-P4-ID-PCE-2016-0731, Con- tract No. 39/2017.
• Role: Co-I. In charge of efficient and reduced order modelling of the large-scale net- work systems for optimisation, simulation and distributed control.
• PI: Prof. Ion Necoara˘ , ACSE, UPB, Romania.
• I have contributed with several ideas and have written the large-scale model approx- imation part of the grant proposal. I have studied the submission procedure at the UEFISCDI and thoroughly followed the submission and the peer review procedure.
• Excellence in Research Grant
• September 2017 – present Excellence in Research Grant from UPB, GEX2017, Con- tract no. 16/25.09.2017.
• Role: PI. I have been awarded €5,000 for research by UPB.
• I have written the grant proposal, won and awarded the contract.
• Short Term Scientific Mission (STSM)
• September 2017 – October 2017 STSM37646 at the University of Groningen, the Netherlands.
• Role: PI. I have been awarded €2,500 for 30 days by The EU COST Action TD1307.
• I have written the grant proposal, won and awarded the contract.
• Travel Grant
• March 2015 – June 2015 at the University of Groningen, the Netherlands.
• Role: Co-I. I have been awarded €6,000 for four months by The Netherlands Organ- isation for Scientific Research (NWO).
• PI: Dr. Orest V. Iftime, Associate Professor at the Faculty of Economics and Business, University of Groningen.
• I have contributed with several ideas and have written the grant proposal. I have mastered the submission procedure at the NWO and I have thoroughly followed and responded to the peer review procedure.
• Travel Grant
• April 2011 – August 2011 at the University of Groningen, the Netherlands.
• Role: Co-I. I have been awarded €6,000 for four months by The Netherlands Organisation for Scientific Research (NWO).
• PI: Dr. Orest V. Iftime, Faculty of Economics and Business, University of Groningen.
• I have contributed with several ideas and have written two sections of the grant proposal. I have studied the submission procedure at the NWO and I have thoroughly followed the submission and the peer review procedure.
• Other grant applications
• January 2017: – Young Research Teams grant application to the National Executive Unit for Funding Higher Education, Research and Innovation (UEFISCDI) of the National Education Department of the Romanian Government. potential duration: two years. Budget awarded if won: €100.000.
• September 2014 – Marie Curie European Individual Fellowship application for a 24 month re- search job at the University of Groningen, the Netherlands within the Horizon2020 Funding Pro- gramme. The title of the proposed research is ”Model order reduction for infinite-dimensional port-Hamiltonian systems”. Funding body: The European Commission.
• December 2008 – Rubicon Grant early career stage application for two year research visit to the Dept. of Mechanical Engineering, University of Nagoya, Japan. Funding body: The Netherlands Organisation for Scientific Research (NWO).
• February 2009 – JSPS Fellowship early career stage two year fellowship application. Fellowship to take place at the University of Nagoya, Japan. Funding body: Japan Society for Promotion of Science (JSPS).
• March 2014 – Royal Society International Exchange Scheme travel grant application – pend- ing review. Research visit to take place at the Dept. of Economics, Econometrics & Finance, University of Groningen, the Netherlands. Funding body: The Royal Society, UK.
Networking
• Research Visits
• April – July 2011 research visit at Dr. Orest Iftime, in the Dept. of Economics, Econo- metrics & Finance, University of Groningen, the Netherlands.
• March – June 2008 research visit at Prof. Kenji Fujimoto, in the Dept. of Mechanical Engineering, Nagoya University, Japan.
• March – May 2007 research visit at Prof. Romeo Ortega, in the Laboratoire de Sig- naux et Systemes, Supelec, France.
Evidence of esteem
• Invited Talks
• July 2011: Invited talk at the 7th Congress of Romanian Mathematicians, Bras¸ov, Romania. Title: ”Moment matching for finite and infinite dimensional systems”.
• May 2011: Invited talk at the Systems Theory Seminar of the Faculty of Mathemat- ics and Natural Sciences, University of Groningen, the Netherlands. Title: ”Moment matching for linear and nonlinear systems”.
• July 2010: Mini-course (1 lecture) at the the European Consortium fr Mathematics in Industry Conference, Wuppertal, Germany. Title: ”Model reduction for nonlinear systems – overview of nonlinear balancing and moment matching”.
• April 2008: Colloquium at the Department of Mechanical Science and Engineering, Nagoya University, Japan. Title: ”Balancing for Passive Systems”.
• January 2008: Invited speaker at the Numerical Mathematics Working Party (NWNP), NXP Semiconductors, Eindhoven, the Netherlands. Title: ”Balancing for Nonlinear Passive Systems”.
• May 2007: Short course (2 lectures) at the Laboratoire de Signaux et Syste`mes, Supe´lec, France. Title: ”Model reduction based on balancing”.
Membership of professional bodies
• November 2007 – present: IEEE Member.
Publications
• Disseminated in the journal and conference papers described in the attached file Tudor C. Ionescu – List of publications.
Top publications
Journal papers – refereed
1. T. C. Ionescu, O.V. Iftime and I. Necoara. Model reduction with pole-zero placement and high order moment matching. Automatica, 132, https://doi.org/10.1016/j.automatica.2021.110140.
2. I. Necoara and T. C. Ionescu. H2 Model Reduction of Linear Network Systems by Mo- ment Matching and Optimization. IEEE Transactions on Automatic Control, ISSN 0018-9286, 65(12):5328-5335 2020.
3. T. C. Ionescu. Two-sided time-domain moment matching for linear systems. IEEE Transactions on Automatic Control, ISSN 0018-9286, 61(9):2632-2637, 2016.
4. T. C. Ionescu and A. Astolfi. Nonlinear moment matching based model order reduction. IEEE Transactions on Automatic Control, ISSN 0018-9286, 61(10):2837-2847, 2016.
5. T. C. Ionescu, A. Astolfi and P. Colaneri. Families of moment matching based, low order approximations for linear systems. Systems & Control Letters, 64: 47–56, 2014.
6. T. C. Ionescu and A. Astolfi. Families of moment matching based, structure preserving ap- proximations for linear port Hamiltonian systems. Automatica, 49(8):2424–2434, 2013.
7. T. C. Ionescu, K. Fujimoto and J. M. A. Scherpen. Singular value analysis of nonlinear sym- metric systems. IEEE Transactions on Automatic Control, 56(9):2073–2086, 2011.
8. T. C. Ionescu, K. Fujimoto and J. M. A. Scherpen. Dissipativity preserving balancing for nonlinear systems – a Hankel operator approach. Systems & Control Letters, 59:180–194, 2010.
Books and chapters Journal papers – submitted
• T. C. Ionescu, O. V. Iftime and I. Necoara. Model reduction with pole-zero placement and matching of derivatives. Automatica, submitted March 2020.
• I. Necoara and T. C. Ionescu. OPTIMAL H2 MOMENT MATCHING-BASED MODEL REDUC- TION FOR LINEAR SYSTEMS BY (NON)CONVEX OPTIMIZATION. International Journal of
Nonlinear and Robust Control, submitted 2020.
Journal papers – in preparation
• X. Cheng, T. C. Ionescu and M. Patrascu. Time-Domain Moment Matching for Second-Order Systems. In preparation, 2020.
• T. C. Ionescu and C. Oara. Moment matching based closed-loop reduction to achieve stabili- sation and asymptotic performance. In preparation, 2020.
• T. C. Ionescu, G. C. Flutur and J. M. A. Scherpen. Families of time-domain momentmatching- based models for descriptor systems. In preparation, 2020.
• T. C. Ionescu, A. Astolfi and R. Barbulescu. Nonlinear moment matching-based model order reduction with preservation of physical properties. In preparation, 2020.
• T. C. Ionescu and O. V. Iftime. Moment matching for infinite-dimensional systems. In prepara- tion, 2015.
Conference papers – refereed
1. R. Barbulescu, G. Ciuprina, T. C. Ionescu, D. Ioan, and L. M. Silveira. Efficient model reduction of myelinated compartments as port-Hamiltonian systems. Proc. Scientific Computing in Electrical Engineering, to appear 2020.
2. T. C. Ionescu, O. V. Iftime and I. Necoara. Optimal time-domain moment matching with partial placement of poles and zeros. Proc. European Control Conference, pp. 1769-1774, 2020, DOI: 10.23919/ECC51009.2020.9143783.
3. T. C. Ionescu, O. V. Iftime and Q.-C. Zhong. Model reduction by moment matching: case study of a FIR system. Proc. European Control Conference, pp. 2319–2324, 2019.
4. I. Necoara and T. C. Ionescu. Parameter selection for best H2 moment matching-based model approximation through gradient optimization. Proc. European Control Conference, pp. 2301– 2306, 2019.
5. T. C. Ionescu and O. V. Iftime. A moment matching approach for systems of delayed differential equations. Proc. European Control Conference, pp. 2605–2610, 2018.
6. T. C. Ionescu and I. Necoara˘ . A scalable moment matching-based model reduction technique of linear networks. Proc. of the 20th IFAC World Congress, 2017.
7. P. Schulze, T. C. Ionescu and J. M. A. Scherpen. Families of moment matching-based reduced order models for linear descriptor systems. Proc. of European Control Conf., pages 1964-1969, 2016.
8. T. C. Ionescu and O. V. Iftime. On moment matching of transfer functions and their derivatives. Proc. of European Control Conf., pages 2104-2109, 2015.
9. T. C. Ionescu and A. Astolfi. Moment matching based controller reduction for linear systems. Proc. of 52nd IEEE Conf. on Decision and Control, 2013.
10. T. C. Ionescu and A. Astolfi. Moment matching for nonlinear port Hamiltonian and gradient systems. Proc. of 9th IFAC Symposium on Nonlinear Control Systems, 2013.
11. O. V. Iftime and T. C. Ionescu. On an approximation with prescribed zeros of SISO abstract boundary control systems. Proc. of European Control Conference, 2013.
12. T. C. Ionescu and A. Astolfi. Families of reduced order models that achieve nonlinear moment matching. Proc. of the American Control Conference, 2013.
13. T. C. Ionescu, J. M. A. Scherpen, O. V. Iftime and A. Astolfi. Balancing as a moment match- ing problem. Proc. 20th International Symposium on Mathematical Theory of Networks and Systems.
14. T. C. Ionescu and O. V. Iftime. Moment matching with prescribed poles and zeros for infinite- dimensional systems. Proc. American Control Conference, Montreal, Canada, 2012.
15. T. C. Ionescu and A. Astolfi. Moment matching for linear systems – overview and new results. Proc. 11th IFAC World Congress, 2010.
16. T. C. Ionescu and A. Astolfi. On moment matching with preservation of passivity and stability. In Proc. 49th IEEE Conference on Decision and Control, 2010.
17. T. C. Ionescu, K. Fujimoto and J. M. A. Scherpen. Positive and bounded real balancing for nonlinear systems – a controllability and observability function approach. In Proc. 48th IEEE Conf. on Decision and Control, pages 4310–4315, 2009.
18. T. C. Ionescu, K. Fujimoto and J. M. A. Scherpen. The cross operator and the singular value analysis for nonlinear symmetric systems. In Proc. European Control Conference ECC09, pages 1565–1570, 2009.
19. T. C. Ionescu and J. M. A. Scherpen. Passivity preserving model order reduction for the SMIB. In Proc. 47th IEEE Conf. on Decision and Control, pages 4879 – 4884, 2008.
20. T. C. Ionescu and J. M. A. Scherpen. Nonlinear cross Gramians and gradient systems. In
Proc. 46th IEEE Conf. on Decision and Control, pages 3745 – 3750, 2007.
Other papers – Book chapters, refereed
1. A. Dumitrache, F. Frunzulica˘ and T. C. Ionescu. Mathematical Modelling and Numerical Inves- tigations on the Coanda Effect. In J. Awrejcewicz and P. Hagedorn, editors, Nonlinearity, Bifur- cation and Chaos – Theory and Applications, ISBN 978-953-51-0816-0, DOI: 10.5772/50403, 2012.
2. T. C. Ionescu and J. M. A. Scherpen. Nonlinear cross Gramians. In A. Korytowski, K. Malanowski,
W. Mitkowski, and M. Szymkat, editors, System Modeling and Optimization, volume 312 of IFIP Advances in Information and Communication Technology, pages 293–306. Springer, 2009.
3. T. C. Ionescu and R. S¸ tefan. Stability analysis of neutral systems: a delay-dependent criterion. to appear in Topics in Time-Delay Systems: Analysis, Algorithms and Control, Springer series Lecture Notes in Control and Information Sciences, 2008.
4. T. C. Ionescu and J. M. A. Scherpen. Positive real balancing for nonlinear systems. In
G. Ciuprina and D. Ioan, editors, Scientific Computing in Electrical Engineering, volume 11 of
ECMI, pages 153–160. Springer, 2007.
1. T. C. Ionescu and R. S¸ tefan. A comparison method for the stability analysis of neutral systems. In J.-J. Loiseau, S.-I. Niculescu, V. Ra˘ svan, and D. Selis¸teanu, editors, Re´union ECO-NET Dynamique – Interconnexions – Environnement, pages 68–73. Editura Universitaria Craiova, Romania, 2007.