Diana Otrocol

Academic degree:

Ph.D. in Mathematics (2006)

Current position:

Scientific researcher III at Tiberiu Popoviciu Institute of Numerical Analysis

Domains of research:

  • Nonlinear operators and differential equations
  • Approximation techniques of the solutions of the delay differential equations
  • The study of convergence of iterations of positive and linear operators

(version of September 17, 2020)

Personal Data

Date and place of birth March 1975, Sibiu
Civil status Married
E-mail dotrocol[at]ictp.acad.ro, diana.otrocol[at]gmail.com

Education and degrees:

2006 Ph.D. in Numerical Analysis
Babeş-Bolyai University, Cluj-Napoca
Thesis: Contributions to the theory of Lotka-Voltera systems with retarted argument
Scientific advisor: prof. dr. Petru Blaga
2001-2002 Master Studies at Faculty of Mathematics and Computer Science, “Lucian Blaga” University, Sibiu;
1993-1997 Faculty of Mathematics and Computer Science, “Babeş-Bolyai” University, section Mathematics, Cluj-Napoca;
1989-1993 High-school “Gheorghe Lazăr”, Sibiu, section mathematics-physics;

Employment history:

2011 – present scientific researcher III at Tiberiu Popoviciu Institute of Numerical Analysis (ICTP), Romanian Academy
2008 – 2011 scientific researcher at ICTP
2006 – 2008 research assistant at ICTP
2002 – 2006 PhD student, Faculty of Mathematics and Computer Science, “Babeş-Bolyai” University, Cluj-Napoca, Romania
1997 – 2002 high school teacher

Teaching Experience

  • Seminars and laboratories taught at the ”Babeş-Bolyai” University Cluj-Napoca (differential equations and dynamical systems, numerical analysis, probabilities, statistics) 2002-2006.

Book

  • D. Otrocol, Lotka-Volterra Systems with delays, Editura Presa Universitara Clujeana, 2007 (in Romanian), ISBN 978-973-610-589-0.

Conferences and workshops:

Books

Papers

  1. D. Otrocol, V. Ilea, A. Novac, Fixed point results for non-self operators R₊m-metric spaces, Fixed Point Theory, 26 (2025) no. 1, 177-188, https://doi.org/10.24193/fpt-ro.2025.1.10
  2. V. Ilea, D. Otrocol, Integral equation with maxima via fibre contraction principle, Journal Fixed Point Theory, 25 (2024) 2, pp. 601-610, http://doi.org/10.24193/fpt-ro.2024.2.10
  3. G. Motronea, D. Otrocol, I. Rasa, Perov’s theorem applied to systems of equations, Modern Mathematical Methods, 1 (2023) no. 1, pp. 22-29.
  4. A. Novac, D. Otrocol, D. Popa, On Ulam stability of a partial differential operator in Banach spaces, Mathematics, 11 (2023) no. 11, art. no. 2488, https://doi.org/10.3390/math11112488
  5. V. Ilea, A. Novac, D. Otrocol, R. Precup, Nonlinear alternatives of hybrid type for nonself vector-valued maps and application, Fixed Point Theory, 24 (2023) no. 1, 221-232, http://doi.org/10.24193/fpt-ro.2023.1.11
  6. V. Ilea, D. Otrocol, I.A. Rus, M.-A. Serban, Applications of fibre contraction principle to some classes of functional integral equations, Fixed Point Theory, 23 (2022) no. 1, 279-292, http://doi.org/10.24193/fpt-ro.2022.1.18
  7. V. Ilea, D. Otrocol, On a Volterra integral equation with delay, via w-distances, Mathematics 9 (2021), art. id. 2341, 8 pp., https://doi.org/10.3390/math9182341
  8. V. Ilea, D. Otrocol, Functional differential equations with maxima, via step by step contraction principle, Carpathian J. Math., 37 (2021) no. 2, pp. 195-202, DOI: 10.37193/CJM.2021.02.05
  9. A. Novac, D. Otrocol, D. Popa, Ulam stability of a linear difference equation in locally convex spaces, Results Math., 76, 33 (2021). https://doi.org/10.1007/s00025-021-01344-2
  10. A.M. Acu, A. Maduta, D. Otrocol, I. Raşa, Inequalities for information potentials and entropies, Mathematics 2020, 8(11), 2056; https://doi.org/10.3390/math8112056, IF: 1.747
  11. V. Ilea, A. Novac, D. Otrocol, R. Precup, Solutions with a prescribed interval of positivity for differential systems with nonlocal conditions, Appl. Math. Comput., 375 (2020), doi: 10.1016/j.amc.2020.125092
  12. V. Ilea, D. Otrocol, Existence and uniqueness of the solution for an integral equation with supremum, via w-distances, Symmetry 2020, 12, 1554, https://doi.org/10.3390/sym12091554
  13. V. Ilea, D. Otrocol, On the Burton method of progressive contractions for Volterra integral equations, Fixed Point Theory, 21 (2020) no. 2, 585-594.
  14. T. Cătinaș, D. Otrocol, Iterates of Cheney-Sharma type operators on a triangle with curved side, J. Comp. Anal. Appl., 28 (2020) no. 4,  pp. 737-744.
  15. A. Aral, D. Otrocol, I. Raşa, On approximation by some Bernstein–Kantorovich exponential-type polynomials, Periodica Mathematica Hungarica, 79 (2019) 2, pp. 236-254.
  16. A. Măduța, D. Otrocol, I. Rașa, Inequalities for indices of coincidence and entropies, Arxiv:1910.13491, 2019.
  17. D. Otrocol, Qualitative properties of solutions for mixed type functional-differential equations with maxima, Miskolc Mathematical Notes, 20 (2019) no. 2, pp. 1119-1128
  18. D. Otrocol, M.A. Serban, An efficient step method for a system of differential equations with delay, J. Appl. Anal. Comput. 8 (2018) no. 2, pp. 498-508.
  19. B.C. Dhage, D. Otrocol, Dhage iteration method for approximating solutions of nonlinear differential equations with maxima, Fixed Point Theory, 19 (2018) no. 2, pp. 545-556.
  20. V. Ilea, D. Otrocol, Some properties of solutions to a planar system of nonlinear differential equations, Studia Univ. Babes-Bolyai Math., 63 (2018) no. 2, pp. 225-234.
  21. D. Otrocol, V. Ilea, On the qualitative properties of functional integral equations with abstract Volterra operators, Res. Fixed Point Theory Appl., vol. 2018 (2018), Article ID 201813, 08
    pp.
  22. V.A. Ilea, D. Otrocol, An application of the Picard operator technique to functional integral equations, J. Nonlinear Convex Anal., 18 (2017) no. 3, pp. 405-413.
  23. D. Otrocol, Hybrid differential equations with maxima via Picard operators theory, Stud. Univ. Babes-Bolyai Math. 61 (2016), no. 4, 421-428.
  24. D. Otrocol, On the asymptotic equivalence of a differential system with maxima, Rend. Circ. Mat. Palermo, Ser. 2, 65 (2016) no 3, pp. 387-393.
  25. T. Catinas, D. Otrocol, I.A. Rus, The iterates of positive linear operators with the set of constant functions as the fixed point set, Carpathian J. Math., 32 (2016) no. 2, pp. 165-172.
  26. V. Ilea, D. Otrocol, I. A. Rus, Some properties of solutions of the homogeneous nonlinear second order differential equations, Mathematica, 57 (80) (2015), no 1-2, pp. 38-43
  27. D. Otrocol, V. Ilea, C. Revnic, Addendum to the paper “an iterative method for a functional-differential equation of second order with mixed type argument“, Fixed Point Theory, 14(2013) no. 2, 427-434, Fixed Point Theory, 16 (2015) no. 1, pp. 191-192.
  28. V.A. Ilea, D. Otrocol, Some properties of solutions of a functional-differential equation of second order with delay, The Scientific World Journal, Volume 2014 (2014), Article ID 878395
  29. D. Otrocol, V.A. Ilea, Qualitative properties of functional differential equation, Electron. J. Qual. Theory Differ. Equ., 2014, No. 47, 1-8.
  30. D. Otrocol, Systems of functional-differential equations with maxima, of mixed type, Electron. J. Qual. Theory Differ. Equ., 2014, No. 5, 1-9.
  31. T. Cătinaş, D. Otrocol, Iterates of multivariate Cheney-Sharma operators, Journal of Computational Analysis and Applications,15 (2013) no. 7, 1240-1246.
  32. D. Otrocol, V.A. Ilea, Ulam stability for a delay differential equation, Central European Journal of Mathematics, 11 (2013) no. 7, 1296-1303.
  33. D. Otrocol, V.A. Ilea, C. Revnic, An iterative method for a functional-differential equation of second order with mixed type argument, Fixed Point Theory, 14 (2013), no.2, 427-434.
  34. T. Cătinaş, D. Otrocol, Iterates of Bernstein type operators on a square with one curved side via contraction principle, Fixed Point Theory, vol. 14 (2013) no.1, 97-106.
  35. D. Otrocol, Properties of the solutions of a system of differential equations with maxima, via weakly Picard operator theory, Communications in Applied Analysis, 17 (2013), no.1, 99-108.
  36. V. Ilea, D. Otrocol, M.-A. Şerban, D. Trif, Integro-differential equation with two time lags, Fixed Point Theory, 13 (2012), no. 1, pp. 85-97.
  37. V.A. Ilea, D. Otrocol, On a D.V. Ionescu’s problem for functional-differential equations of second order, Proceedings of the 10th IC-FPTA, July 9-18, 2012, Cluj-Napoca, Romania, pp. 131–142.
  38. V.A. Ilea, D. Otrocol, Integro-differential equation with two times modifications, Carpathian J. Math., 27 (2011) no. 2, pp. 209-216.
  39. D. Otrocol, Ulam stabilities of differential equation with abstract Volterra operator in a Banach space, Nonlinear Functional Analysis and Applications, 15, 2010, no. 4, pp. 613-619 (pdf file here).
  40. D. Otrocol, V. Ilea C. Revnic, An iterative method for a functional-differential equation with mixed type argument, Fixed Point Theory, vol. 11 (2010) no. 2, 327-336 (pdf file also here).
  41. V.Ilea, D.Otrocol, On a D.V. Ionescu’s problem for functional-differential equations, Fixed Point Theory, 10 (2009) no. 1, pp. 125-140.
  42. D. Otrocol, I.A. Rus, Functional-differential equations with “maxima” via weakly Picard operators theory, Bull. Math. Soc. Sci. Math. Roumanie, 51(99) 2008, no. 3, 253-261.
  43. D. Otrocol, Abstract Volterra operators, Carpathian J. Math. 24 (2008) no. 3, 370-377.
  44. D. Otrocol, I.A. Rus, Functional-differential equations with maxima of mixed type, Fixed Point Theory 9 (2008), no. 1, 207-220 (pdf file here).
  45. D. Otrocol, A differential equation with delay from biology, J. Appl. Math. & Informatics, 26 (2008) nos. 5-6, pp. 1037–1048.
  46. Ş. M. Şoltuz, D. Otrocol, Classical results via Mann-Ishikawa iteration, Rev. Anal. Numér. Théor. Approx., 36 (2007), no. 2, 195-199 (pdf file also here).
  47. Ş. M. Şoltuz, D. Otrocol, The convergence of Mann iteration with delay, Mathematical Sciences Research, 2007, Vol. 11, no. 3, pp. 390-393 (pdf file here).
  48. D. Otrocol, Differentiability with respect to delays for a Lotka-Volterra system, Creative Math. and Inf., 2007, Vol. 16, pp. 36-41 (tech. rep. here).
  49. D. Otrocol, Smooth dependence on paramters for a differential equation with delay from population dynamics,  2007 International Conference on Engineering and Mathematics, Bilbao, July 9-11, 2007, pp. 3-10.
  50. D. Otrocol, Data dependence of the fixed points set for a Lotka-Volterra system, Proceedings of the International Conference on Numerical Analysis and Approximation Theory, Cluj-Napoca, Romania, July 5-8, 331-336, 2006 (pdf file here).
  51. D. Otrocol, Differentiability with respect to a parameter for a Lotka-Volterra system with delays, via step method, Rev. Anal. Numér. Théor. Approx., 35 (2006), no. 1, 83-86 (pdf file here).
  52. D. Otrocol, Iterative functional-differential system with retarded argument, Rev. Anal. Numér. Théor. Approx., 35 (2006), no. 2, 147-160 (pdf file alsohere).
  53. D. Otrocol, Numerical solutions of Lotka-Volterra system with delay by spline functions of even degree, Studia Univ. Babeş-Bolyai, Mathematica, Vol 51, no. 4, 167-180, 2006 (pdf file here).
  54. D. Otrocol, Data dependence for the solution of a Lotka-Volterra system with two delays, Mathematica, Tome 48(71), No. 1 (2006), 61-68.
  55. D. Otrocol, Smooth dependence on parameters for some Lotka-Volterra system with delays, Analele Universităţii din Timişoara, Seria Matematică-Informatică, Vol. XLIII, fasc. 1, 2005, 109-114 (pdf file also here).
  56. D. Otrocol, A numerical method approximating the solution of a Lotka-Volterra system with two delays, Studia Univ. Babeş-Bolyai, Mathematica, Vol L. No.1, 2005, 99-110(pdf file here).
  57. D. Otrocol, Lotka-Volterra system with two delays, via weakly Picard operators, Nonlinear Analysis Forum, 10 (2), pp. 193-199, 2005 (pdf file here).