Dr. Călin-Ioan Gheorghiu
Ph.D. in Mathematics (1984, Bucharest University, Mathematics and Mechanics Faculty)
Senior researcher at Tiberiu Popoviciu Institute of Numerical Analysis
Professor at “Lucian Blaga” University, Sibiu (between 1999-2010)
Current research domains:
- Spectral methods (collocation, Galerkin, tau)
- Numerical analysis of dynamical systems
- Mathematical modeling of some physics-chemical hydrodynamical phenomena
Past research activity:
- Finite element and finite differences type methods
|Date and place of birth||September 27, 1950, Alba-Iulia, Romania|
Education and degrees
|1984||Ph.D. in Mathematics
Bucharest University, Faculty of Mathematics and Mechanics
Scientific advisor: Acad. Caius Iacob
Thesis: Finite Element Method in some Problems of Viscous Fluid Mechanics
|1973-1974||Master of Science in Fluid Mechanics
Babeş-Bolyai University, Faculty of Mathematics and Mechanics, Cluj-Napoca
Scientific advisor: Prof. Dr. I. Stan
Thesis: Numerical methods for establishing the concentration in flows involving chemical reactions over a rotating disk
|1969-1973||Bachelor Degree, Mathematics
Babeş-Bolyai University, Faculty of Mathematics and Mechanics, Cluj-Napoca
|1965-1969||“Horia Cloşca şi Crişan” High School, Alba-Iulia|
Further experiences and training
|September 2002||Computer Simulation of Surfaces and Interfaces, NATO ASI, Varna, Bulgaria|
|April 2001||Complexity from Microscopic to Macroscopic Scales; Coherence and Large Deviations, NATO Advances Study Institute, Geilo, Norway|
|Visiting researcher at Oxford University, OCIAM & Computing Laboratory (Soros Scholarship), UK|
|Microlocal Analysis and Spectral Theory, NATO Advanced Study Institute Course, Univ. Torino, Italy|
|September 1995||Control of Flow Instabilities and Unsteady Flows, International Centre for Mechanical Sciences (CISM) Udine, Italy|
|September 1990||Variational Methods in Mechanics, Szombathely, Hungary|
|September 1990||Mathematical Modeling of Industrial Processes, SASIAM, Tecnopolis-Bari, Italy|
|September 1987||Non-Smooth Mechanics and Applications, International Centre for Mechanical Sciences (CISM) Udine, Italy|
|September 1986||Finite and Boundary Element Techniques from Mathematical and Engineering Point of View, International Centre for Mechanical Sciences (CISM) Udine, Italy|
|2014-present||Senior Researcher (I) at “Tiberiu Popoviciu” Institute of Numerical Analysis (ICTP), Romanian Academy|
|1995-2013||Senior Researcher (II) at ICTP|
|1990-1995||Senior Researcher (III) at ICTP|
|1988-1990||mathematician, Babeş-Bolyai University, Faculty of Mathematics|
|1978-1988||mathematician, Technical University Cluj-Napoca, Department of Civil Engineering and Computing Center|
|1974-1978||hydrologist, Institute of Meteorology and Hydrology, Bucharest, Cluj Sector|
Courses in charge
|Feb. 08-Mar. 16 2010||Visiting professor at Abdus Salam School of Mathematical Sciences (ASSMS) , Lahore, Pakistan, Numerical methods for nonlinear dynamical systems; Numerical analysis; MATLAB|
|Jul. 01-Oct. 30 2008; Jul. 01- Sept. 20 2010||Visiting professor at African University of Science and Technology, Abuja, Nigeria, Numerical methods for nonlinear dynamical systems; Numerical analysis; Partial differential equations; MATLAB|
|1999-2010||Professor at “L. Blaga” University, Sibiu, Numerical methods for dynamical systems; Differential equations|
|Aug. 01-Oct. 20 2005||Visiting professor at King Mongkut Institute of Technology, Ladkrabang, Bangkok, Thailand, Numerical methods for nonlinear dynamical systems; Numerical analysis|
|Feb. 21-Jul. 05 2005||Visiting professor at Nanjing University for Astronautics and Aeronautics, College of Sciences, Nanjing, China, Finite elements method; Numerical analysis|
|Jun. 01-Sept. 30 1999||Visiting professor at King Mongkut Institute of Technology, Ladkrabang, Bangkok, Thailand, Finite element and numerical modeling courses|
|1998-1999||Associate professor at Department of Mathematics, Technical University Cluj-Napoca , Mathematical analysis, Differential geometry|
|Jun. 01-Sept. 30 1997||Visiting professor at King Mongkut Institute of Technology, Ladkrabang, Bangkok, Thailand, Finite element and numerical analysis courses|
|1995-1996||Associate professor at Faculty of Mathematics and Computer Science, Babeş-Bolyai University, Numerical methods in hydrodynamics|
Selected Meetings and Symposia
- the annual meetings of Academic Days of Cluj and Conferences for Applied and Industrial Mathematics ROMAI (former Annual Colloquia of Fluid Mechanics and its Technical Applications)
- the meetings of GAMM (2), ECMI (1), ICM (1), Euromech Colloquia (2), ICIAM (1)
- The Eighth Congress of Romanian Mathematicians, 2015, Iaşi, Romania
Membership in professional societies
- Geselltschaft fur Angewandte Mathematik und Mechanik (GAMM), member
- European Cooperation in Science and Technology (COST), member
- European Mechanics Society (EUROMECH), member
- Romanian Society of Industrial and Applied Mathematics ROMAI-member, elected vice-president;
- European Consortium for Mathematics in Industry (ECMI), former member
- Society of the Romanian Mathematicians SSMR, member.
- 2-CEx06-11-96/19.09.2006-2008, MEC, Efficient numerical methods with applications on supercomputers (participant)
- 7037/2001/ , MEC, Numerical methods for dissipative dynamical systems (coordinator)
- 6100/13.10.2000, ANSTI, Numerical analysis of nonlinear parabolic dynamical systems (coordinator)
- 4122/1998-1999, MCT, Numerical methods for the qualitative study of some nonlinear dynamical systems (coordinator)
- GAR-29/1996, Numerical methods for the study of the eigenvalues of some bilocal problems. Applications in hydrodynamical stability and subcritical transition to turbulence (coordinator)
Other professional activities
- Reviewer for: Zentralblatt fur Mathematik, Acta Applicandae Mathematicae (The Netherlands), Studia Universitatis “Babeş-Bolyai” Math. (Cluj-Napoca, Romania)
- Scientific evaluator for Umm Al-Qura University Journal of Science-Medicine-Engineering and for Permanent Committee for Academic Promotion, King Abdulaziz University (Saudi Arabia)
- Scientific reviewer for some ISI journals: HFF, Microfluidics and Nanofluidics (MANO), Applied Mathematics and Computation, Advances in Computation, APNUM, JOEMS, British Journal of Mathematics & Computer Science, ASME Journal of Computational and Nonlinear Dynamics, etc.
- “Simion Stoilow” award of Romanian Academy, for the monograph Finite Element Method and Applications, Romanian Academy Publishing House, Bucharest, 1987 (with T. Petrila)
- Operating systems: Windows
- Programming languages: MATLAB, Fortran, Scientific Word (Latex), Power Point
- English, French, Russian
- J. Rodriguez-Lopez, R. Precup, C.-I. Gheorghiu, On the localization and numerical computation of positive radial solutions for φ-Laplace equations in the annulus, Electronic Journal of Qualitative Theory of Differential Equations, 2022, no. 47, pp. 1-22, doi.org/10.14232/ejqtde.2022.1.47
- C.-I. Gheorghiu, Chebfun solutions to a class of 1D singular and nonlinear boundary value problems, Computation, 10 (2022) no. 7, art. id. 116, http://doi.org/10.3390/computation10070116
- C.I. Gheorghiu, Accurate spectral collocation computations of high order eigenvalues for singular Schrödinger equations-revisited, Symmetry, 13 (2021) 5, https://doi.org/10.3390/sym13050761
- C.I. Gheorghiu, Accurate spectral collocation solutions to 2nd-order Sturm–Liouville problems, Symmetry, 13 (2021) 3, 385, doi: 10.3390/sym13030385
- C. I. Gheorghiu, Accurate spectral collocation computation of high order eigenvalues for singular Schrödinger equations, Computation, 9 (2021) 2, 19 pp. https://doi.org/10.3390/computation9010002
- C. I. Gheorghiu, Accurate spectral collocation solutions to some Bratu’s type Boundary Value Problems, arXiv:2011.13212
- C. I. Gheorghiu, Spectral collocation solutions to second order singular Sturm-Liouville eigenproblems, Symmetry, 13 (2021) 3, doi: 10.3390/sym13030385
- C.I. Gheorghiu, Spectral collocation based on quasi-classical orthogonal polynomials applied to solve a singular BVP from hydrodynamics, AIP Conference Proceedings 2293, 100004 (2020); https://doi.org/10.1063/5.0026783
- C.I. Gheorghiu, B. Zinsou, Analytic vs. numerical solutions to a Sturm-Liouville transmission eigenproblem, J. Numer. Anal. Approx. Theory, 48 (2019) no. 2, 159-174.
- C.I. Gheorghiu, Spectral collocation solutions to a class of pseudo-parabolic equations, G. Nikolov et al. (Eds.): NMA 2018, LNCS 11189, pp. 1–8, 2019. doi: 10.1007/978-3-030-10692-8_20
- C.I. Gheorghiu, On the numerical treatment of the eigenparameter dependent boundary conditions, Numerical Algorithms, 77 (2018) no. 1, pp 77–93, DOI: 10.1007/s11075-017-0305-1
- C.I. Gheorghiu, Stable spectral collocation solutions to Cauchy problems for nonlinear dispersive wave equations, Proceedings of the 4th Conference of Mathematical Society of Moldova (CMSM4), 2017, pp. 277-280. ISBN 978-9975-71-915-5
- J.P. Boyd, C.I. Gheorghiu, All roots spectral methods: Constraints, floating point arithmetic and root exclusion, Applied Mathematics Letters 67 (2017) 28–32 DOI: 10.1016/j.aml.2016.11.015 (IF 2016: 2.233)
- C.I. Gheorghiu, Spectral collocation solutions to systems of boundary layer type, Numer. Algor., 73 (2016) no. 1, pp 1–14, doi: 10.1007/s11075-015-0083-6
- C.I. Gheorghiu, Stable spectral collocation solutions to a class of Benjamin Bona Mahony initial value problems. Appl. Math. Comp., 273 (2016) 1090-1099. (Impact factor 2014: 1.551)
- B. Plestenjak, C.I. Gheorghiu, M.E. Hochstenbach, Spectral collocation for multiparameter eigenvalue problems arising from separable boundary value problems. J. Comput. Phys. 298 (2015) 595-601. (Impact factor 2014: 2.434)
- C.I. Gheorghiu, Pseudospectral solutions to some singular nonlinear BVPs. Applications in nonlinear mechanics. Numer. Algor., 68 (2015) 1-14. (Impact factor 2013: 1.042)
- C.I. Gheorghiu, Laguerre collocation solutions vs. analytic results for singular semilinear BVPs on the half line, ROMAI J., 11 (2015), pp. 69-87.
- C.I. Gheorghiu, C. Morosanu, Accurate spectral solutions to a phase-field transition system, ROMAI J., 10 (2014) 2, 1-11.
- C.I. Gheorghiu, On the accuracy of pseudospectral differentiation. ROMAI J., 10 (2014) 1, 55-62.
- C.I. Gheorghiu, Laguerre collocation solutions to boundary layer type problems. Numer. Algor., 64 (2013) 385-401. (Impact factor 2012: 1.042)
- C.I. Gheorghiu, J. Rommes, Application of the Jacobi-Davidson method to accurate analysis of singular linear hydrodynamic stability problems. Int. J. Numer. Meth. Fluids, 71 (2013) 358-369. (Impact factor 2012: 1.293)
- C.I. Gheorghiu, M.E. Hochstenbach, B. Plestenjak, J. Rommes, Spectral collocation solutions to multiparameter Mathieu’s system, Appl. Math. Comput., 218 (2012) 11990-12000. (Impact factor 2011: 1.317)
- I.F. Dragomirescu, C.I. Gheorghiu, Analytical and numerical solutions to an electrohydrodynamic stability problem. Appl. Math. Comput., 216 (2010) 3718-3727. (Impact Factor 2009: 1.124)
- C.I. Gheorghiu, F.-I. Dragomirescu, Spectral methods in linear stability. Applications in thermal convection with variable gravity field, Appl. Numer. Math., 59 (2009) 1290-1302. (Impact Factor 2009: 1.207)
- C.I. Gheorghiu, Accurate numerical solutions to stationary free surface problems from capillarity, Phys. Part. Nuclei Lett., 5 (2008), 286-289.
- C.I. Gheorghiu, A.C. Mureşan, On the long time energy conservation by high order geometric integrators, PADEU, 19 (2007), 213-219.
- C.I. Gheorghiu, A.C. Mureşan, On the accuracy of Stoermer/Verlet method as the numerical integrator of the n-body problem – Application to solar system, Rom. Astron. J., 16 (2006) 93-102.
- C.I. Gheorghiu, Nonlinear deterministic dynamics with applications, Preprint King Mongkut’s Institute of Technology, Ladkrabang, Bangkok, Thailand, 53 pp., Octomber, 2005.
- C.I. Gheorghiu, On spectral properties of Chebyshev-type methods. Dimensions vs. structure, Studia Univ. Babeş-Bolyai Math. Cluj-Napoca, L (2005) 61-66.
- C.I. Gheorghiu, On the scalar measure of non-normality of matrices – dimension vs. structure, General Mathematics, 11 (2003) nos. 1–2, 21–32.
- C.I. Gheorghiu, On some one-step implicit methods as dynamical systems, Rev. Anal. Numér. Théor. Approx., 32 (2003) 171-175.
- C.I. Gheorghiu, A. Mureşan, On the significance of integral properties of orbits in some superlinear fixed-period problems, Seminar on Fixed Point Theory, Cluj-Napoca, 3 (2002) 223-230.
- C.I. Gheorghiu, D. Trif, Direct and indirect approximations to positive solution for a nonlinear reaction-diffusion problem. Part I. Direct (variational) approximation, Rev. Anal. Numér. Théor. Approx. 31 (2002) 61-70.
- C.I. Gheorghiu, D. Trif, Direct and indirect approximations to positive solution for a nonlinear reaction-diffusion problem. Part II. Indirect approximation, Rev. Anal. Numér. Théor. Approx. 31 (2002) 171-178.
- C.I. Gheorghiu, E. Borşa, On the flow of a viscous thin layer on an inclined solid plane driven by a constant surface tension gradient, Rev. Anal. Numér. Théor. Approx. 30 (2001) 127-134.
- C.I. Gheorghiu, D. Trif, On the bifurcation and variational approximation of the positive solution of a nonlinear reaction-diffusion problem, Studia Univ. Babeş-Bolyai Math., XLV (2000) 29-37.
- E. Borşa, C.I. Gheorghiu, On the Marangoni flow on an inclined plane, Bul. Inst. Politehnic din Iaşi, Supliment Mecanica Fluidelor, XLVI(L) (2000) 61-64.
- E. Borşa. C. I. Gheorghiu, On the Marangoni and gravity flow in an inclined channel of an arbitrary section, Rev. Roum. Sci Techn.-Mec. Appl., 45 (2000) 255-264.
- C.I. Gheorghiu, A unified treatment of boundary layer and lubrication approximations in viscous fluid mechanics, Rev. Anal. Numér. Théor. Approx., 29 (2000) 135-138.
- C.I. Gheorghiu, D. Trif, The numerical approximation to positive solution for some reaction-diffusion problems, PU.M.A., 11 (2000) no. 2, 243-253.
- C.I. Gheorghiu, The solution to problem 97-8 by Ph. Korman, SIAM Rev., 39 (1997), SIAM Rev., 40 (1998) 382-385.
- C.I. Gheorghiu, Al. Tămăşan, On the bifurcation of the null solutions of some boundary value problems, An. St. Univ. Ovidius Constanta, Seria Matematica, 5 (1997), 59-64.
- E. Chifu, E. Gavrila, M. Sălăjan, C.I. Gheorghiu, Surface mobility of surfactant solutions, XVII. Determination of Marangoni rate of flow in simulated zero gravity conditions, J. Roum. Colloid Surface Chem. Assoc., 2 (1997), pp. 25-29.
- I.S. Pop, C.I. Gheorghiu, A Chebyshev-Galerkin method for fourth order problems, Proceedings of ICAOR (International Conference on Approximation and Optimization – Romania), Cluj-Napoca, July-August 1996, vol. II, pp. 217-220.
- C.I. Gheorghiu, On the behavior of a thin liquid layer flowing due to gravity and a surface tension gradient, I. Mathematical aspects, Studia Univ. Babeş-Bolyai Math., XLI (1996) 47-54.
- C.I. Gheorghiu, Comment on ”Numerical analysis for the effect of surfactants on a circular liquid lens I”, Rev. Roum. Sci. Techn. – Mec. Appl., 41 (1996) nos. 5-6, p. 493.
- C.I. Gheorghiu, T. Petrila, On the motion of a drop due to a surface tension gradient, Proceedings of ICAOR (International Conference on Approximation and Optimization – Romania), 1996, vol. II, pp. 117-118.
- C.I. Gheorghiu, I.S. Pop, A modified Chebyshev-tau method for a hydrodynamic stability problem, Proceedings of ICAOR (International Conference on Approximation, Optimization – Romania), 1996, vol. II, pp. 119-126.
- C. I. Gheorghiu, S.I. Pop, On the Chebyshev-tau approximation for some singularly perturbed two point boundary value problems – Numerical experiments, Rev. Anal. Numér. Théor. Approx. 24 (1995) 117-124.
- C.I. Gheorghiu, Al. Tămăşan, On the existence and uniqueness of positive solutions of some mildly nonlinear elliptic boundary value problems, Rev. Anal. Numér. Théor. Approx. 24(1995) 125-129.
- E. Chifu, C.I. Gheorghiu, M. Sălăjan, E. Gavrila, Marangoni and gravity flows in thin liquid layers, ITEC 1995, International Thermal Energy Congress, Morocco, June 5-8, 1995, published by E. Bilgen, A. Mir, T.H. Nguyen, P. Vasseur, Eds, vol.II, Ecole Polytechnique de Montreal, 1995, pp. 832-837.
- C.I. Gheorghiu, M. Kohr-Ile, An integral formulation for some slow viscous flows with free surfaces, Mathematica, 36 (59) (1994), pp. 43-54.
- E. Chifu, E. Gavrila, M. Sălăjan, C.I. Gheorghiu, Surface mobility of surfactant solutions. XVI. Involvement of the fluid viscosities in the Marangoni flow – some aspects, Studia Univ. Babeş-Bolyai Chemia XXXIX (1994), pp. 159-166.
- C.I. Gheorghiu, Z. Kasa, I. Stan, Effects of surfactants on an undeformable drop initially at rest, Studia Univ. Babeş-Bolyai Math., XXXVIII (1993) 113-126.
- C.I. Gheorghiu, On the competition between Marangoni and gravity forces to determinate the surface profiles of a liquid flow on an inclined plane open to air, Preprint nr. 2, 1989, Research Seminar on Mechanics, ”Babeş-Bolyai” Univ. Cluj-Napoca, Faculty of Mathematics and Physics, pp. 47-52.
- C.I. Gheorghiu, On a linear singularly perturbed two point boundary value problem, Preprint nr. 1, 1989, Seminar on Functional Analysis and Numerical Methods, “Babeş-Bolyai” Univ. Cluj-Napoca, Faculty of Mathematics and Physics.
- C.I. Gheorghiu, On the use of Green’s formula for solution of the Navier-Stokes equation, Adv. Water Reources, 14 (1991) 113-117.
- C.I. Gheorghiu, FEM and/or BEM for numerical simulation of Marangoni flow, Eng. Anal. Bound. Elem., 5 (1988) 195-197 (former Eng. Anal.)
- C.I. Gheorghiu, E. Chifu, Surface mobility of surfactant solutions XII, Remarks concerning the Marangoni flow through an inclined surface canal, Rev. Roumaine Chim., 32 (1987) nos. 9-10, pp. 945-951.
- E. Chifu, C.I. Gheorghiu, I. Stan, Some remarks concerning the Marangoni flow on an inclined plane, Proceedings of the VI-th International Tagung über Grenzflächenaktive Stoffe, 1985, Akad. Verlag, Berlin, 1987, pp. 211-217.
- E. Culea, C.I. Gheorghiu, Al. Nicula, Electrical Conductivity of Vitreous 75% V2O5-25%(As2O3-B203), Physica Status Solidi (a), 96 (1986) no. 1, pp. K85-K88.
- E. Chifu, I. Albu, C.I. Gheorghiu, E. Gavrila, M. Sălăjan, M. Tomoaia-Cotisel, Marangoni flow -induced by temperature gradients- against gravity forces, Rev. Roumaine Chim. 31 (1986) no. 1, 105-112.
- E. Chifu, C.I. Gheorghiu, I. Stan, Surface mobility of surfactant solutions. XI Numerical analysis for the Marangoni and the gravity flow in a thin liquid layer of triangular section, Rev. Roumaine Chim., 29 (1984) no. 1, pp. 31-42.
- C.I. Gheorghiu, Finite element methods for the general quasi harmonic equation, Preprint nr. 1, 1982, Seminar of Numerical Approximation Method in Hydrodynamics and Heat Transfer, ”Babeş-Bolyai” Univ. Cluj-Napoca, Faculty of Mathematics.
- I. Stan, C.I. Gheorghiu, Numerical methods for the flows with chemical reactions over a rotating disk, Studia Univ. Babeş-Bolyai Math., 25 (1980) no. 4, 24-31 (in Romanian).
- L. Ilie, C.I. Gheorghiu, Numerical simulation of rain-runoff process within the Zalău drainage, at the Sărmăşag gauging point, Hidrotehnica, 24 (1979) no. 7, 157-160 (in Romanian).
- I. Stan, C.I. Gheorghiu, The shooting method in establishment of concentration profiles in diffusive boundary layer, St. Cerc. Mec. Apl., 37 (1978) no. 3, 353-360. (in Romanian)
- I. Stan, C.I. Gheorghiu, Numerical methods in establishment of concentration profile for the flows with chemical reactions over rotating disk, Studia Univ. Babeş-Bolyai Math., 22 (1977) no. 1, 73-77 (in Romanian).
version of December 4, 2022.