Статии в списания

  1. S. Harizanov, I. Lirkov, S. Margenov, Rational Approximations in Robust Preconditioning of Multiphysics Problems, Mathematics, 10 (5) (2022), 780, https://doi.org/10.3390/math10050780
  2. S. Harizanov, N. Kosturski, I. Lirkov, S. Margenov, Y Vutov, Reduced Multiplicative (BURA-MR) and Additive (BURA-AR) Best Uniform Rational Approximation Methods and Algorithms for Fractional Elliptic Equations, Fractal and Fractional, 5 (3) (2021),61, https://doi.org/10.3390/fractalfract5030061
  3. S. Harizanov, N. Kosturski, S. Margenov, Y. Vutov, Neumann fractional diffusion problems: BURA solution methods and algorithms, Mathematics and Computers in Simulation, 189 (2021), 85-98, https://doi.org/10.1016/j.matcom.2020.07.018
  4. S. Harizanov, R. Lazarov, S. Margenov, P. Marinov, J. Pasciak, Analysis of numerical methods for spectral fractional elliptic equations based on the best uniform rational approximation, Journal of Computational Physics (2020), https://doi.org/10.1016/j.jcp.2020.109285
  5. S. Harizanov, R. Lazarov, S. Margenov, A survey on numerical methods for spectral space-fractional diffusion problems, Fractional Calculus and Applied Analysis, 23(6) (2020),1605-1646, https://doi.org/10.1515/fca-2020-0080
  6. S. Harizanov, R. Lazarov, S. Margenov, P. Marinov, Numerical solution of fractional diffusion–reaction problems based on BURA, Computers & Mathematics with Applications 80 (2) (2020), 316-331, https://doi.org/10.1016/j.camwa.2019.07.002
  7. S. Harizanov, R. Lazarov, S. Margenov, P. Marinov, J. Pasciak, Analysis of numerical methods for spectral fractional elliptic equations based on the best uniform rational approximation, Journal of Computational Physics (2020), https://doi.org/10.1016/j.jcp.2020.109285
  8. R. Čiegis, V. Starikovičius, S. Margenov, R. Kriauzienė, Scalability analysis of different parallel solvers for 3D fractional power diffusion problems, Concurrency and Computation: Practice and Experience 31 (19)(2019), e5163
  9. S. Harizanov, R. Lazarov, S. Margenov, P. Marinov, Numerical solution of fractional diffusion–reaction problems based on BURA, Computers & Mathematics with Applications (2019), https://doi.org/10.1016/j.camwa.2019.07.002
  10. S. Harizanov, R. Lazarov, S. Margenov, P. Marinov, Y. Vutov, Numerical Linear Algebra with Applications 25 (5) (2018), e2167
  11. R. Čiegis, V. Starikovičius, S. Margenov, R. Kriauzienė, Parallel solvers for fractional power diffusion problems, Concurrency and Computation: Practice and Experience 29 (24) (2017), e4216
  12. R. Blaheta, I. Georgiev, K. Georgiev, O. Jakl, R. Kohut, S. Margenov, J. Starý, High Performance Computing Applications, Cybernetics and Information Technologies 17 (5) (2017), 5-16
  13. V. Kyovtorov, I. Georgiev, S. Margenov, D. Stoychev, F. Oliveri, D Tarchi, New antenna design approach – 3D polymer printing and metalization: experimental test at 14–18 GHz, AEU - International Journal of Electronics and Communications 73 (2017), 119-128
  14. S. Stoykov, S. Margenov, Numerical methods and parallel algorithms for computation of periodic responses of plates, Journal of Computational and Applied Mathematics 310 (2017), 200-212
  15. S. Harizanov, S. Margenov, P. Marinov, Y. Vutov, Volume constrained 2-phase segmentation method utilizing a linear system solver based on the best uniform polynomial approximation of x^{−1/2}, Journal of Computational and Applied Mathematics 310 (2017), 115-128
  16. S. Stoykov, E. Manoach, S. Margenov, An efficient 3D numerical beam model based on cross sectional analysis and Ritz approximations, ZAMM Zeitschrift fur Angewandte Mathematik und Mechanik 96(7)(2016), 791-812
  17. J. Kraus, R. Lazarov, M. Lymbery, S. Margenov, L. Zikatanov, Preconditioning heterogeneous h(div) problems by additive Schur complement approximation and applications, SIAM Journal on Scientific Computing 38(2) (2016), A875-A898
  18. S. Stoykov, S. Margenov, Scalable parallel implementation of shooting method for large-scale dynamical systems. Application to bridge components, Journal of Computational and Applied Mathematics 293 (2015), 223-231
  19. R.F. Sviercoski, P. Popov, S. Margenov, An analytical coarse grid operator applied to a multiscale multigrid method, Journal of Computational and Applied Mathematics, Vol. 287 (15) (2015), 207-219
  20. M. Mihajlovic, L. A. Bongo, R. Ciegis, N. Frasheri, D. Kimoski, P. Kropf, S. Margenov, M. Neytcheva, T. Rauber, G. Runger, R. Trobec, R. Wuyts, R. Wyrzykowski, J. Gong, Applications for ultrascale computing, Supercomputing frontiers and innovations, Vol.2 (1) (2015). 19-48
  21.  J. Kraus, M. Lymbery, S. Margenov, Robust Multilevel Methods for Quadratic Finite Element Anisotropic Elliptic Problems, Numer. Linear Algebra Appl., Vol. 21 (3) (2014) ISSN 1099-1506, 375-398
  22. Kraus, J., Lymbery, M., and Margenov, S. Auxiliary space multigrid method based on additive Schur complement approximation, Numer. Linear Algebra Appl. (2014) DOI: 10.1002/nla.1959
  23. S. Stoykov, S. Margenov, Nonlinear Vibrations of 3D Laminated Composite Beams, Mathematical Problems in Engineering (2014) Article ID 892782, DOI: 10.1155/2014/892782
  24. I. Georgiev, S. Margenov, Semi-coarsening AMLI preconditioning of anisotropic trilinear FEM, 2014, 67, Systems, Computers and Mathematics with Applications, 67 (2014)        doi:10.1016/j.camwa.2014.07.030, 2103–2111
  25. S. Stoykov, S. Margenov, Numerical computation of periodic responses of nonlinear large-scale systems by shooting method, Computers & Mathematics with Applications, 67 (2014) doi:10.1016/j.camwa.2014.07.030,  2257-2267
  26. J. Kraus, M. Lymbery, S. Margenov, Robust Multilevel Methods for Quadratic Finite Element Anisotropic Elliptic Problems, Numerical Linear Algebra With Applications (2013), DOI: 10.1002/nla.1876
  27. Y. Efendiev, J. Galvis, R. Lazarov, S. Margenov, J. Ren, Robust Two-level Domain Decomposition Preconditioners for High-contrast Anisotropic Flows in Multiscale Media, Comput. Methods Appl. Math, Volume 12, Issue 4 (2012), 415-436
  28. Lymbery, M., Margenov, S.: Robust Semi-Coarsening Multilevel Preconditioning of Biquadratic FEM Systems, Cent. Eur. J. Math. 10(1) (2012), 357-369, DOI: 10.2478/s11533-011-0082-3, IF: 0.581
  29. P. Boyanova, I. Georgiev, S. Margenov, and L. Zikatanov, Multilevel preconditioning of graph-Laplacians: Polynomial approximation of the pivot blocks inverses, Math. Comp. Simulation (2012), http://dx.doi.org/10.1016/j.matcom.2012.06.009, IF: 0.738
  30. P. Boyanova, S. Margenov, Robust Multilevel Methods for Elliptic and Parabolic Problems, chapter in: O. Axelsson, J. Karatson, Efficient Preconditioning Methods for Elliptic Partial Differential Equations, Bentham Science Publishers (2011), eISBN 978-1-60805-291-2, 3-22
  31. M. Lymbery,S. Margenov, Robust Semi-Coarsening Multilevel Preconditioning of Biquadratic FEM Systems, Cent. Eur. J. Math. (2011), DOI 10.2478/s11533-011-0082-3
  32. P. Boyanova, S. Margenov, M. Neytcheva, Robust AMLI Methods for Time-dependent FEM Systems, J. Comp. Appl. Math. (2010), 380-390, IF: 1.138
  33. P. Boyanova, S. Margenov, On Multilevel Iterative Methods for Navier-Stokes Problems, Journal of Theoretical and Applied Mechanics, vol. 40, No. 1, vol. 40 (2010), 51-60
  34. S. Margenov, N. Kosturski, MIC(0) preconditioning of 3D FEM problems on unstructured grids: conforming and non-conforming elements, Journal of Computational and Applied  Mathematics, 226 (2009), 288-297, IF: 1.138
  35. I. Georgiev, J. Kraus, S. Margenov, J. Schicho, Loacally optimized MIC(0) preconditioning of Rannacher-Turek FEM systems, Applied Numerical Mathematics, 59 (2009), 2402 - 2415
  36. J. Kraus, S. Margenov and J. Synka, On  the multilevel preconditioning of Crouzeix-Raviart elliptic problems Numerical Linear Algebra with Applications, 15 (2008), 395-416
  37. P. Arbenz, S. Margenov, Y. Vutov, Parallel MIC(0) preconditioning of 3D elliptic problems discretized by Rannacher-Turek finite elements, Computers and Mathematics with Applications, 55 (10) (2008), 2197-2211
  38. I. Georgiev, J. Kraus,  S. Margenov, Multilevel preconditioning of rotated bilinear non-conforming FEM problems, Computers and Mathematics with Applications, 55 (10) (2008), 2280-2294
  39. W. Kuranowski, M. Ganzha, M. Gawinecki, M. Paprzycki, I. Lirkov, S. Margenov, Forming and managing agent teams acting as resource brokers in the Grid-preliminary considerations, International Journal of Computational Intelligence Research, 4 (1) (2008), 9-16
  40. I. Georgiev, J. Kraus, S. Margenov, Multilevel algoritms for Rannacher-Turek finite element approximation of 3D elliptic problems, Computing, 82(2008), 217-239
  41. S. Margenov, Y. Vutov,  Preconditioning of Voxel FEM Elliptic Systems, TASK, Quaterly, 11, No 1-2 (2007), 117-128
  42. R.D. Lazarov, S.D. Margenov, CBS constants for multilevel splitting of graph-Laplacian and application to preconditioning of discontinuous Galerkin systems, Journal of Complexity, 23 (2007), 498-515
  43. S. Margenov, P. Minev, On a MIC(0) preconditioning of non-conforming mixed FEM elliptic problems, Mathematics and Computers in Simulation, 76 (2007), 149-154
  44. I. Georgiev, S. Margenov, Element preconditioning technique for rotated bilinear FEM elliptic systems, Mathematica Balkanica, Vol. 20 (2006), 39-48
  45. I. Georgiev, J. Kraus,  S. Margenov, Two-level algorithms for Rannacher-Turek FEM, Problems in Programming, Sc. J., 2-3 (2006), 694-700
  46. O. Axelsson, L. Laayouni, S. Margenov, Robust multilevel preconditionersfor second order elliptic equations and systems of equations, Mathematica Balkanica, Vol. 19 (2005), 321-348
  47. R. Blaheta, S. Margenov, M.Neytcheva, Robust optimal multilevel preconditioners for non-conforming finite element systems, Numerical Linear Algebra with Applications, 12 (2005), 495-514
  48. G. Bencheva, S. Margenov, Performance analysis of parallel MIC(0)preconditioning of rotated bilinear nonconforming FEM systems, Mathematica Balkanica, Vol. 17 (3-4) (2003), 319-335
  49. R. Blaheta, S. Margenov, M.Neytcheva, Uniform estimate of the constant in the strengthened CBS inequality for anisotropic non-conforming FEM systems, Numerical Linear Algebra with Applications, Vol. 11 (4) (2004), 309-326
  50. I. Georgiev, S. Margenov, DD-MIC(0) preconditioning of rotated trilinear FEM elasticity systems, Journal of Computer Assisted Mechanics and Engineering Sciences, 11(2004), 197-209
  51. O. Axelsson, S. Margenov, On multilevel preconditioners which are optimal with respect to both problem and discretization parameters, Computational Methods in Applied Mathematics, Vol. 3 (1) (2003),6-22
  52. G. Bencheva, S. Margenov, Parallel incomplete factorization  preconditioning of rotated linear FEM systems, Journal of Computational and Applied Mechanics, V.4(2) (2003), 105-117
  53. Tz. Kolev, S. Margenov, Two-level preconditioning of pure displacement non-conforming FEM systems}, Numerical Linear Algebra with Applications, 6 (1999), 533-555
  54. A. Georgiev, S. Margenov, M. Neytcheva, Multilevel algorithms for 3D simulation of nonlinear elasticity problems, Mathematics and Computers in Simulation, 50 (1999), 175-182
  55. S. Margenov, Semicoarsening AMLI algorithms for elasticity problems, Numerical Linear Algebra with Applications, 5 (1998), 347-362
  56. I. Lirkov, S. Margenov, L. Zikatanov, Circulant block-factorization preconditioning of anisotropic problems,  Computing, Vol. 58(3) (1997), 245-258
  57. T. Chan, S. Margenov, P. Vassilevski, Performance of block-ILU factorization preconditioners based on block-size reduction for 2D elasticity systems, SIAM J. Sci. Comp., 18 (1997), 1355-1366
  58. R. Ewing, S. Margenov, P. Vassilevski, Preconditioning the biharmonic equation by multilevel iterations,  Mathematika Balcanica, Vol.10(1996), 121-132
  59. S. Margenov, J. Maubach, Optimal algebraic multilevel preconditioning for local refinement along a line, Numerical Linear Algebra with Applications, Vol.2, No.4 (1995), 317-334
  60. R.E. Ewing, O.P. Iliev, S.D. Margenov, P.S. Vassilevski, Numerical study of three multilevel preconditioners for solving 2D Navier-Stokes equations, Comput. Methods Appl. Mech. Engrg., 121 (1995), 177-186
  61. S. Margenov, Upper bound of the constant in the strengthened C.B.S. inequality for FEM 2D elasticity equations, Numerical Linear Algebra with Applications, Vol. 1(1) (1994), 65-74
  62. I. Lirkov, S. Margenov, P.S. Vassilevski, Circulant block-factorization preconditioners for elliptic problems, Computing, Vol.53(1) (1994), 59-74
  63. S. Margenov, P.S. Vassilevski, Algebraic multilevel preconditioning of anisotropic elliptic problems, SIAM J. Sci. Comp., V.15(5) (1994), 1026-1037
  64. K. Georgiev, S. Margenov, On domain decomposition preconditioning of plane elasticity problems, Mathematica  Balkanica, Vol. 6 (2) (1992), 173-181
  65. K. Georgiev, S. Margenov, On  the  domain  decomposition  methods for elliptic problems with discontinueses  coefficients, Numerical Algorithms, Vol. 12 (1992), 281-292
  66. V. Eijkhout, S. Margenov, Preconditioned iterative solution of spline finite element systems, Mathematica Balkanica, Vol.4 (1990), 350-367
  67. N. Grozev, S. Margenov, Automatic  static  solution  of  curvilinear shell bridge structures, Roads, Vol. 8, Sofia (1983), 16-18 (in Bulgarian)
  68. S. Margenov, An application of parabolic and cubic splines to solution of mixed boundary value problems of fourth order on a rectangle, Serdica, Vol. 7, Sofia (1981), 211-216 (in Russian)
  69. N. Grozev, S. Margenov, An application of parabolic  splines  to  static solution of curvilinear bridge plates, Roads, Vol. 3, Sofia (1980), 8-10 (in Bulgarian)