# Institute annual report 2019

## Human resources:

The Numerical Analysis and Approximation Theory workgroup:

- Dr. Emil
**Cătinaş**(workgroup coordinator) - Prof. Dr. Ion
**Păvăloiu**(from January to March 2019) - Prof. Dr. Octavian
**Agratini** - Dr. Diana
**Otrocol** - Dr. Flavius
**Pătrulescu** - Mihai
**Nechita** - Imre
**Boros** - Cristian-Daniel
**Alecsa**

The Numerical Modeling workgroup:

- Dr. Călin-Ioan
**Gheorghiu**(workgroup coordinator) - Dr. Nicolae
**Suciu** - Dr. Maria
**Crăciun**

## PhD advisors

- Dr. rer. nat. habil. Nicolae
**Suciu**supervises PhD theses.

He has recently supervised the thesis*Filtered density functions for uncertainty assessment of transport in groundwater*, by Lennart Schüler, defended on September 8, 2016, at Jena University, Germany; the thesis received the distinction*Magna Cum Laudae*. - Prof. dr. Ion
**Păvăloiu**has supervised in the past 8 PhD theses at North University of Baia-Mare and at Babeş-Bolyai University. - Prof. dr. Octavian
**Agratini**, who supervises PhD theses at Babes-Bolyai University.

## Books published in 2019

## Papers published in 2019 in JCR/ISI indexed journals:

**Survey papers**

- E. Cătinaş,
*A survey on the high convergence orders and computational convergence orders of sequences*, Appl. Math. Comput., 343 (2019) 1-20. (2018 SRI 0.97, IF 3.092)

**Papers** - E. Burman,
__M. Nechita__, L. Oksanen,*Unique continuation for the Helmholtz equation using stabilized finite element methods*, J. Math. Pures Appl. 129 (2019), pp. 1-22. (SRI 3.7, IF 1.961,)

(rem.: M. Nechita is a PhD student at UCL, London) - V. Moisoiu, A. Socaciu, A. Stefancu, S.D. Iancu,
__I. Boros, C. Alecsa__, C. Rachieriu, A.R. Chiorean, D. Eniu, N. Leopold, C. Socaciu, D. Eniu,*Breast cancer diagnosis by surface-enhanced Raman scattering (SERS) of urine*, Appl. Sci. (2019), 9(4), 806; (SRI 0.93, IF 2.217) - A. Aral,
__D. Otrocol__, I. Raşa,*On approximation by some Bernstein–Kantorovich exponential-type polynomials*, Period. Math. Hung. (2019) 79: 236. (SRI 0.51, IF 0.664) __D. Alecsa__,*Common fixed points for Presic operators via simulation functions*, J. Nonlin. Conv. Analysis, 20 (2019) no. 3, 363-377. (SRI 0.35, IF 0.595) ISSN 1345-4773__M. Crăciun__, T. Harko,*Constraining Bose-Einstein condensate dark matter models with the galaxy rotation curves of the SPARC sample*, Romanian Astronomical Journal, 29 (2019) no.2, 101-118.- V. Moisoiu, A. Stefancu, S. D. Iancu, T. Moisoiu, L. Loga, L. Dican, C. D. Alecsa, I. Boros, A. Jurj, D. Dima, C. Bagacean, R. Tetean, E. Burzo, C. Tomuleasa, F. Elec, N. Leopold,
*SERS assessment of the cancer-specific methylation pattern of genomic DNA: towards the detection of acute myeloid leukemia in patients undergoing hematopoietic stem cell transplantation*, Anal. Bioanal. Chem. 411 (2019) no. 29, pp. 7907–7913. (doi: 10.1007/s00216-019-02213-2) - D. Alecsa, Approximating fixed points for nonlinear generalized mappings using Ishikawa iteration, Rendiconti del Circolo Matematico di Palermo, Series 2,
**68**(2019), 163-191. - C.D. Alecsa,
*Sequences of contractions on cone metric spaces over Banach algebras and applications to nonlinear systems of equations and systems of differential equations*, International J. Nonlin. Anal. Appl., 10 (2019) 2, pp. 227-254, DOI: 10.22075/ijnaa.2019.18884.2040 - D. Otrocol,
*Qualitative properties of solutions for mixed type functional-differential equations with maxima*, Miskolc Mathematical Notes, 20 (2019) no. 2, pp. 1119-1128.

**Note: paper by Catinas was published in 2018, but with coordinates for 2019.**

## Papers published in other journals/preprints:

__Agratini__,*Shift λ – invariant operators*, Constructive Mathematical Analysis, 2 (2019) 3, 103-108. DOI http://doi/org/10.33205/cma.544094__Agratini__,*From uniform to statistical convergence of binomial-type operators*, In: Advances In Summability And Approximation Theory, 169 – 179, (Eds. S. A. Mohiuddine, T. Acar), Springer, Singapore, 2018. ISBN: 978-981-13-3076-6, DOI https://doi.org/10.1007/978-981-13-3077-3_10- T. Catinas,
__D. Otrocol__,*Iterates of Cheney-Sharma type operators on a triangle with curved side*, J. Comput. Anal. Appl., 28 2020 no. 4, 737-744. __D. Alecsa, I. Boros, T. Pinta__,*New optimization algorithms for neural network training using operator splitting techniques*, Arxiv 1904.12952, https://arxiv.org/pdf/1904.12952.pdf (preprint)- Maduta,
__D. Otrocol__, I. Rasa,*Inequalities for indices of coincidence and entropies*, arXiv: 1910.1349 (preprint)

## Papers accepted in other journals:

__D. Alecsa__, A. Petrusel,*Some variants of Ciric’s multi-valued contraction principle*, Annals of West University of Timisoara – Mathematics and Computer Science, 2019.

Papers published online in 2019 in JCR (ISI) papers, with doi codes

- O. Pătrulescu, T. Groşan, I. Pop, Natural convection from a vertical plate embedded in a non-Darcy bidisperse porous medium, ASME-Journal of Heat Transfer (2019), DOI: https://doi.org/10.1115/1.4045067. (ISSN: 0022-1481). IF: 1.479. (rem: paper published in 2019, with coordinates in 2020)
- C.-D. Alecsa, S.C. László, A. Viorel, A gradient-type algorithm with backward inertial steps associated to a nonconvex minimization problem, Numer. Algor., https://doi.org/10.1007/s11075-019-00765-z
- C.I. Gheorghiu, Spectral Collocation Based on Quasi-Classical Orthogonal Polynomials Applied to Solve a Singular BVP from Hydrodynamics, AIP Publishing, (accepted, to appear)

## Prizes

C.D. Alecsa, *Diploma Academiei Romane privind rezultate remarcabile cu privire la teoria si programarea metodelor numerice*, May 14 2019. (Romanian Academy Diploma for: remarkable results regarding theory and practice of numerical methods)

## Members of Editorial Boards

- Studia UBB Math.: O. Agratini
- J. Numer. Anal. Approx. Theory: E. Catinas, O. Agratini, D. Otrocol, M. Nechita, I. Boros
- ROMAI Journal: N. Suciu, C.I. Gheorghiu
- Mathematica (Cluj): O. Agratini
- Open Journal of Discrete Mathematics: O. Agratini
- J. Science and Arts: O. Agratini

## Conferences organized

Symposium:* Numerical Analysis, Approximation and Modeling*, Cluj-Napoca, April 16, 2019.

**Rem.:** with the participation of Prof. C. Cartis (Univ. of Oxford).

## Conferences attended by the members of the Institute

**International conferences**

__Suciu__,*Global random walk solutions for flow in porous media*(poster), EGU General Assembly 2015, Vienna, April, 7–12, 2019, https://meetingorganizer.copernicus.org/EGU2019/posters/30957__Suciu__,*Global random walk solutions for flow in porous media*(prezentare orala), European Numerical Mathematics and Advanced Applications Conference 2019, 30th sep – 4th okt 2019, Egmond aan Zee, The Netherlands, https://www.enumath2019.eu/program/day/4?man_id=536- Harko,
__M. Crăciun__, S. Liang, Testing the Bose-Einstein dark matter model with galactic rotation curves from the SPARC sample, 2019 International Mini Workshop on Composite Higgs, Dark Matter, Neutrinos, New Physics, Gauge-Higgs Unification and Related Topics, Sun Yat-sen University (SYSU), Guangzhou, China, 21-24 November 2019. - I. Gheorghiu,
*Finite element solutions to a Sturm-Liouville transmission eigenproblem*, 90th Annual Meeting of the International Association of Applied Mathematics and Mechanics, 18 – 22 February 2019 University of Vienna, Vienna, Austria. - I. Gheorghiu,
*Spectral Collocation Based on Quasi-Classical Orthogonal Polynomials Applied to Solve a Singular BVP from Hydrodynamics*, ICNAAM 2019, Rhodes, Greece - T. Grosan, I. Pop, F.O. Patrulescu,
*Transfer Phenomena in Non-Darcy Bidisperse Porous Media*, 15th International Conference on Fluid Mechanics (FLUIDS ’19), Athens, Greece, December 8-10, 2019 http://www.wseas.org/multimedia/conferences/2019/Athens-A/Program.pdf - Otrocol (joint work with Adela Novac and Dorian Popa),
*Ulam stability of a linear difference equation in locally convex spaces*, International Conference on Approximation Theory and Its Applications, Alexandru Lupas, 10-13 October, 2019, Sibiu, Romania, http://conferences.ulbsibiu.ro/icata __Agratini__,*Non-Newtonian Calculus and Approximation Theory*, The International Conference on Approximation Theory and its Applications, Sibiu, 10-13 October 2019. (joint work with Harun Karsli)- Otrocol (joint work with Ioan Rasa),
*Functional equations and entropies*, The Eighteenth International Conference on Functional Equations and Inequalities (18 ICFEI), Bedlewo, Poland, June 9 – 15, 2019, https://icfei.up.krakow.pl/

National conferences

__Agratini__,*Approximation processes with flexible nodes*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__I. Gheorghiu__,*Spectral collocation methods based on quasi-classical orthogonal polynomials. Some numerical experiments*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__Pătrulescu, C.D. Alecsa, N. Suciu__,*Numerical solutions (finite element method, finite difference) for a flow problem in aquifers*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__Boros__,*Spectral methods with arbitrary precision for differential problems. Application to a flow problem in heterogeneous aquifers*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__Crăciun__, T. Harko,*About the fitting of a dark matter model on the galactic rotation curves data*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__-C. Anisiu__,*Families of curves and compatible potentials*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__Păvăloiu, E. Cătinaș__,*On the convergence of some iterative methods for nonlinear equations in R*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019__D. Alecsa__,*A gradient type algorithm with backward inertial steps for a nonconvex minimization*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019- Novac,
__D. Otrocol__, D. Popa,*On Ulam stability of a linear difference equation in locally convex spaces*, Numerical Analysis, Approximation and Modeling, Academic Days, Cluj-Napoca, April 16 2019 __Crăciun__, T. Harko,*Galactic rotation curves in Bose-Einstein Condensate dark matter models, Recent developments in astronomy, astrophysics, space and planetary sciences*, Recent developments in astronomy, astrophysics, space and planetary sciences, International Conference, 27-29 May 2019, Cluj-Napoca- Pop,
__M. Crăciun__, V. Turcu,*Detection of a low level period variability in the pulsating star SZ Lyncis*, Recent developments in astronomy, astrophysics, space and planetary sciences, International Conference, 27-29 May 2019, Cluj-Napoca __I. Gheorghiu__*, Two Open Problems Concerning Quasi-Periodic Eigenproblems*, CAIM 2019, Universitatea Valahia, Târgovişte.__I. Gheorghiu__*, On the utility of non-classical orthogonal Polynomials. Boundary value and eigenvalue problems,*ICATA 2019, Universitatea Lucian Blaga, Sibiu.

Others:

- International grant SU 415/4-1 (https://gepris.dfg.de/gepris/projekt/405338726) obtained by dr. rer. habil. N. Suciu from (Deutschefourschungs Gmemeindschaft), for the project
*“Integrated global random walk model for reactive transport in groundwater adapted to measurement spatio-temporal scales”*(01.10.2018-30.09.2021), in progress at Erlangen-Nuernberg University.