![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/ans.png)
Despre noi
Grupul de cercetare se reuneşte săptămânal – marţi de la 14 la 16 în sala “e” a clădirii Mathematica.
Şedinţele au caracter de informare şi documentare relativ la direcţiile de cercetare promovate de colectiv.
Bilunar au loc expuneri plenare.
Direcţii de cercetare:
- teoria aproximării
- metode numerice
- procese liniare de aproximare
- procese aleatoare
- ecuaţii stohastice
- calcul paralel
- matematici financiare
In primul semestru al anului universitar 2021-2022 activitatile se desfasoara exclusiv online.
Colectivul
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/agratini.jpg)
Prof. Dr. Agratini Octavian
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/catinas.jpg)
Conf. Dr. Habil. Cӑtinaş Teodora
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/chiorean.jpg)
Conf. Dr. Chiorean Ioana
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/lisei.jpg)
Conf. Dr. Habil. Lisei Hannelore
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/micula.jpg)
Conf. Dr. Habil. Micula Sanda
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/roscaalin-150x133.jpg)
Conf. Dr. Roșca Alin Vasile
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/rosca.jpg)
Conf. Dr. Roșca Natalia
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/roth.jpg)
Conf. Dr. Róth Ágoston
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/soos.jpg)
Conf. Dr. Soós Anna
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/trimbitas.jpg)
Conf. Dr. Trîmbițaș Radu
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/radu.jpg)
Lect. Dr. Radu Voichița-Adriana
![](https://math.ubbcluj.ro/~ans/wp-content/uploads/2017/11/somogyi.jpg)
Lect. Dr. Somogyi Ildikó
Doctoranzi:
- Malina Andra
- Sutu Madalina
La seminarii participă toți
STUDENȚII DOCTORANZI
care elaborează lucrarea în domeniul de cercetare al grupului.
Seminarii de cercetare
Anul universitar 2020-2021, semestrul I
- 13 octombrie
Vizualizare cu restictii impuse folosind operatorul de interpolare Shepard-Bernoulli (conf. univ. habil. Teodora Cătinaș)
- 3 noiembrie
- 24 noiembrie
Asupra unei metode iterative de rezolvare a ecuatiilor neliniare (invitat: cercet. pr. Emil Cătinaș, Inst. de Calcul T. Popoviciu, Acad. Romana)
- 8 decembrie
Asupra unor metode numerice iterative pentru ecuatii integrale Fredholm cu nucleu singular (conf. univ. habil. Sanda Micula)
- 12 ianuarie
- Punctul de stagnare a unui nanofluid peste o placa nealiniata ce se dilata/contracta cu viteza de alunecare de ordin doi (conf. univ. Natalia Rosca)
Articole notabile
Articole notabile ale membrilor colectivului, aparute incepand cu anul universitar 2017-2018:
- Agratini, O., Aral, A., Approximation of some classes of functions by Landau type operators, RESULTS IN MATHEMATICS, Vol. 76, Article 12, 2021, 15 pages. Doi.org/10.1007/s00025-020-01319-9. [cuartila 2]
- Agratini, O., Approximation properties of a family of integral type operators, POSITIVITY, Vol. 25, Issue 1, 2021, 97 – 108. Doi.org/10.1007/s11117-020-00752-y [cuartila 2]
- Agratini, O., Gal, Sorin G., On Landau-type approximation operators, MEDITERRANEAN JOURNAL OF MATHEMATICS, Vol. 18, Issue 2, Article 64, 2021, 15 pages. Doi.org/10.1007/s00009-021-01712-w [cuartila 2]
- Ágoston Róth, Simple and weighted cyclic proximity curves and surfaces, Computer-Aided Design, Vol. 137 (2021), Article 103043, 28 pages. https://doi.org/10.1016/j.cad.2021.103043 [cuartila 1]
- B.E. Breckner, H. Lisei, Gh.I. Simon, Optimal control results for a class of stochastic Schrodinger equations, Applied Mathematics and Computation 407 (2021), Article Number: 126310. [cuartila 1]
- Noeiaghdam, S., Micula, S., A Novel Method for Solving Second Kind Volterra Integral Equations with Discontinuous Kernel, MATHEMATICS, Vol. 9(17), 2172, 2021, doi: 3390/math9172172 [cuartila 1]
- Micula, S., Groşan, T., Pop, I., Natural convection in a porous square cavity filled with a nanofluid: A numerical study using spline functions, JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, 2021, doi: 10.1007/s10973-021-11001-z [cuartila 1]
- Micula, S., Numerical Solution of Two-Dimensional Fredholm–VolterraIntegral Equations of the Second Kind, SYMMETRY, Vol. 13(8), 1326, 2021, 1-12, doi: 10.3390/sym13081326 [cuartila 2]
- Noeiaghdam, S., Micula, S., Nieto, J. J., A Novel Technique to Control the Accuracy of a Nonlinear Fractional Order Model of COVID-19: Application of the CESTAC Method and the CADNA Library, MATHEMATICS, Vol. 9(12), 1231, 2021, doi: 10.3390/math9121321 [cuartila 1]
- Micula, S., Pop, I., Free convection inside a porous square cavity with convective boundary condition using spline functions, BOUNDARY VALUE PROBLEMS, Vol. 2021(1), 57, 2021, 1 – 13, doi:10.1186/s13661-021-01533-6 [cuartila 1]
- Noeiaghdam, S., Micula, S., Dynamical Strategy to Control the Accuracy of the Nonlinear Bio-Mathematical Model of Malaria Infection, MATHEMATICS, Vol. 9(9), 1031, 2021, doi: 10.3390/math9091031 [cuartila 1]
- Micula, S., Pop, I., Numerical results for the classical free convection flow problem in a square porous cavity using spline functions, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 31(3), 753-765, 2021 (online July 2020), doi: 10.1108/HFF-03-2020-0159 [cuartila 1]
- Micula, S., A Numerical Method for Weakly Singular Nonlinear Volterra Integral Equations of the Second Kind, SYMMETRY, Vol. 12(11), 1862, 2020, doi:10.3390/sym12111862 [cuartila 2]
- Natalia C. Roșca, Alin V Roșca, Ioan Pop, Axisymmetric flow of hybrid nanofluid due to a permeable non-linearly stretching/shrinking sheet with radiation effect, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 31 (2021), No. 7, pp. 2330-2346. [cuartila 1]
- Natalia C. Roşca, Alin V Roşca, Amin Jafarimoghaddam, Ioan Pop, Cross flow and heat transfer past a permeable stretching/shrinking sheet in a hybrid nanofluid, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 31 (2021), No. 4, pp. 1295-1319. [cuartila 1]
- Natalia C Roșca, Alin V Roșca, Ioan Pop, Mixed convection flow of a hybrid nanofluid past a vertical wedge with thermal radiation effect, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, 2021, DOI: https://doi.org/10.1108/HFF-03-2021-0155. [cuartila 1]
- N.S. Khashi’ie, N.M. Arifin, Natalia C. Roşca, Alin V. Roşca, Ioan Pop, Three-dimensional flow of radiative hybrid nanofluid past a permeable stretching/shrinking sheet with homogeneous-heterogeneous reaction, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, 2021, DOI: https://doi.org/10.1108/HFF-01-2021-0017. [cuartila 1]
- E.H. Aly, Alin V. Roşca, Natalia C. Roşca, Ioan Pop, Convective Heat Transfer of a Hybrid Nanofluid over a Nonlinearly Stretching Surface with Radiation Effect, MATHEMATICS, Vol. 9 (2021), no. 18, Article Number 2220, 2021, DOI; https://doi.org/10.3390/math9182220. [cuartila 1]
- Natalia C. Roşca, Ioan Pop, Hybrid Nanofluids Flows Determined by a Permeable Power-Law Stretching/Shrinking Sheet Modulated by Orthogonal Surface Shear, ENTROPY, Vol. 23 (2021), no. 7, Article Number 813, DOI: https://doi.org/10.3390/e23070813. [cuartila 2]
- T. Cătinaş, Nielson interpolation operators on an arbitrary triangle with one curved side, BIT Numerical Mathematics, 61 (2021), no. 3, pp. 757–770; doi: 10.1007/s10543-021-00842-7 [cuartila 1]
- Alin V. Roşca, Natalia C. Roşca, Ioan Pop, Mixed convection stagnation point flow of a hybrid nanofluid past a vertical flat plate with a second order velocity model, Vol. 31 (2021), no. 1, pp. 75 – 91, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW [cuartila 1]
- Jafarimoghaddam, Natalia C. Roşca, Alin V. Roşca, Ioan Pop, The universal Blasius problem: New results by Duan–Rach Adomian Decomposition Method with Jafarimoghaddam contraction mapping theorem and numerical solutions, Vol. 187 (2021), no. 9, pp. 60 – 76, MATHEMATICS AND COMPUTERS IN SIMULATION [cuartila 2]
- Jafarimoghaddam, M. Turkyilmazoglu, Alin V. Roşca, Ioan Pop, Complete theory of the elastic wall jet: A new flow geometry with revisited two-phase nanofluids, Vol. 86 (2021), pp. 25– 36, EUROPEAN JOURNAL OF MECHANICS B-FLUIDS [cuartila 2]
- Ghalambaz, Natalia C. Roşca, Alin V. Roşca, Ioan Pop, Mixed convection and stability analysis of stagnation-point boundary layer flow and heat transfer of hybrid nanofluids over a vertical plate, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 30 (2020), no. 7, pp. 3737 – 3754. [cuartila 1]
- M. Birou, C.V. Muraru, V.A. Radu, Convergence of Certain Baskakov Operators of Integral Type, Symmetry, Vol. 13(9), 2021, 1747. https://doi.org/10.3390/sym13091747 [cuartila 2]
- A.M. Acu, M. Dancs, V.A. Radu, Representations for the inverses of certain operators, Communications on Pure and Applied Analysis, 19(8) (2020), 4097-4109. [cuartila 2]
- Agratini, O., Properties of discrete non-multiplicative operators, ANALYSIS AND MATHEMATICAL PHYSICS, Vol. 9, Issue 1, 2019, 131 – 141. [cuartila 1]
- S. Micula, On some iterative numerical methods for mixed Volterra-Fredholm integral equations, Symmetry, Vol. 11(10), 1200, 2019, 1-10, doi:10.3390/sym11101200 [cuartila 2]
- M. Acu, O. Dogru, C.V. Muraru, V.A. Radu, Approximation Properties of Certain Bernstein–Stancu Type Operators, Journal of Mathematical Inequalities, 13 (3) (2019), 687-702. [cuartila 2]
- M. Acu, T. Acar, C.V. Muraru, V.A. Radu, Some approximation properties by a class of bivariate operators, Mathematical Methods in the Applied Sciences, 42 (2019), 1-15, https://doi.org/10.1002/mma.5515 [cuartila 2]
- M. Acu, T. Acar, V.A. Radu, Approximation by modified $U^{\rho}_n$ operators, Revista de la Real Academia de Cientias Exactas Fisicas Y Naturales Serie A-Matematicas (RACSAM), 113 (3) (2019), 2715-2729, s13398-019-00655-y. [cuartila 1]
- Roşca, N.C., Roşca, A.V., Pop, I., Unsteady separated stagnation point flow and heat transfer past a stretching/shrinking sheet in a copper-water nanofluid, International Journal of Numerical Methods for Heat and Fluid Flow, Vol. 29, Issue 8, pp. 2588-2605, 2019 [cuartila 2].
- Roşca, A.V., Roşca, N.C., Pop, I., Stagnation point flow of a nanofluid past a non-aligned stretching/shrinking sheet with a second order slip velocity, International Journal of Numerical Methods for Heat and Fluid Flow, Vol. 29, Issue 2, pp. 738-762, 2019 [cuartila 2].
- Agratini, O., Approximation with arbitrary order by certain linear positive operators, POSITIVITY, Vol. 22, Issue 5, 2018, 1241 – 1254. [cuartila 2]
- Abel, U., Agratini, O., Păltănea, R., A complete asymptotic expansion for the quasi- interpolants of Gauss-Weierstrass operators, MEDITERRANEAN JOURNAL OF MATHEMATICS, Vol. 15, Issue 4, 2018, Article 156, 10 pages. [cuartila 1]
- Micula, S., An iterative numerical method for fractional integral equations of the second kind, J. Comput. Appl. Math., Vol. 339, 2018, 124-133, doi:10.1016/j.cam.2017.12.006. [cuartila 1]
- Micula, S., Cattani, C., On a numerical method based on wavelets for Fredholm-Hammerstein integral equations of the second kind, Math. Method. Appl. Sci., Vol. 41(18), 2018. 9103-9115, doi:10.1002/mma.4952. [cuartila 2]
- Sheremet, M.A., Roşca, N.C., Roşca, A.V., Pop, I., Mixed convection heat transfer in a square porous cavity filled with a nanofluid with suction/injection effect, Computers & Mathematics with Applications, Vol. 76, Issues 11–12, pp. 2665-2677, 2018 .
- Borrelli, A., Giantesio, G., Patria, Roşca, N.C.,Roşca, A.V., Pop, I., Influence of temperature and magnetic field on the oblique stagnation-point flow for a nanofluid past a vertical stretching/shrinking sheet, International Journal of Numerical Methods for Heat and Fluid Flow, Vol. 28, Issue 12, pp. 2874-2894, 2018 [cuartila 2].
- Pop, I., Roşca, N.C.,Roşca, A.V., MHD stagnation-point flow and heat transfer of a nanofluid over a stretching/shrinking sheet with melting, convective heat transfer and second-order slip, International Journal of Numerical Methods for Heat and Fluid Flow, Vol. 28, Issue 9, pp. 2089-2110, 2018 [cuartila 2]
- Lisei H., Varga Cs., Vas O., Localization method for the solutions of nonhomogeneous operator equations, Applied Mathematics and Computation 329, 64–83 (2018) [cuartila 1]
- Sheremet, M.A., Roşca, A.V., Pop, I., The influence of thermal radiation on unsteady free convection in inclined enclosures filled by a nanofluid with sinusoidal boundary conditions, International Journal of Numerical Methods for Heat and Fluid Flow, Vol. 28, Issue 8, pp. 1738-1753, 2018 [cuartila 2]
- Agratini, O., Aral, A., Deniz, E., On two classes of approximation processes of integral type, POSITIVITY, Vol. 21, Issue 3, 2017, 1189 – 1199. [cuartila 2]
- Cătinaş, T., Extension of some particular interpolation operators to a triangle with one curved side, Applied Mathematics and Computation 315 (2017) 286-297. [cuartila 1]
- Micula, S., On some iterative numerical methods for a Volterra functional integral equation of the second kind, J.Fixed Point Theory Appl., Vol. 19, 2017, 1815–1824, doi:10.1007/s11784-016-0336-6. [cuartila 2]
- Giantesio, G., Verna, A., Roşca, N.C., Roşca, A.V., Pop, I., MHD mixed convection oblique stagnation-point flow on a vertical plate, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 27, no. 12, pp. 2744 – 2767, 2017; [cuartila 2]
- Roşca, N.C., Roşca, A. V., Merkin, J., Pop, I., Mixed convection flow, heat transfer, species concentration near the stagnation point on a vertical flat plate with Stefan coupled blowing, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 27, no. 1, pp. 77 – 103, 2017; [cuartila 2]
- Borrelli, A., Giantesio, G., Patria, M.C., Roşca, N.C., Roşca, A.V., Pop, I., Buoyancy effects on the 3D MHD stagnation-point flow of a Newtonian fluid, COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION, Vol. 43, pp. 1-13, 2017;
- Roşca, N.C., Pop, I., A numerical study of the axisymmetric rotational stagnation point flow impinging radially a permeable stretching/shrinking surface in a nanofluid, INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW, Vol. 27, no. 11, pp. 2415 – 2432, 2017. [cuartila 2]
- Roşca, N.C., Pop, I., Axisymmetric rotational stagnation point flow impinging radially a permeable stretching/shrinking surface in a nanofluid using Tiwari and Das model, SCIENTIFIC REPORTS, Vol. 7, 40299, pp. 1-11, 2017.
- Juhász, I., Róth, A., Adjusting the energies of curves defined by control points, Computer-Aided Design, 107 : 77 – 88, https://doi.org/10.1016/j.cad.2018.09.003; [cuartila 1]
- Róth, A., Algorithm 992: An OpenGL- and C++-based function library for curve and surface modeling in a large class of extended Chebyshev spaces, ACM Transactions on Mathematical Software, Vol. 45, No. 1, Article 13, https://doi.org/10.1145/3284979;