Full CV

(Last updated: July 24, 2024)

 

  

 

TOBB Economics and Technology University,

Department of Mathematics

Söğütözü TR-06530, Ankara, Turkey

E-Mail: oduman@etu.edu.tr; okitayduman@gmail.com

Website: http://oduman.etu.edu.tr/

 

Education:

Academic Employment:

Research Areas:

Awards, Honors, and Grants:

Editorial:

Professional Memberships:

Refereeing:

Duties in Projects and Programs:

Thesis Supervised:

Administrative Duties in the University:

Duties in Conferences:

Courses Taught:

Invited Talks:

International/National Contributed Talks:

Citation Report (ISI Web of Science - Pablons):

Publications:

  1. O. Duman, B. Della Vecchia and E. Erkus-Duman, Kantorovich version of vector-valued Shepard operators, Axioms 13 (2024), Paper No. 181, 12 pp.

  2. O. Duman, Max-product Shepard operators based on multivariable Taylor polynomials, J. Comput. Appl. Math. 437 (2024), Paper No. 115456, 15 pp.

  3. O. Duman and B. Della Vecchia, Vector-valued Shepard processes: Approximation with summability, Axioms, 12 (2023), Paper No. 1124, 16 pp.

  4. C. Turan Yalçın and O. Duman, Regular integral transformations on time scales and generalized statistical convergence, Filomat 37 (2023), no. 12, 4017-4028.

  5. O. Duman and B. Della Vecchia, Approximation to integrable functions by modified complex Shepard operators, J. Math. Anal. Appl. 512 (2022), no. 2, Paper No. 126161, 13 pp.

  6. T. Y. Gökçer and O. Duman, Regular summability methods in the approximation by max-min operators, Fuzzy Sets Systems 426 (2022), 106-120.

  7. O. Duman and B. Della Vecchia, Complex Shepard operators and their summability, Results Math. 76 (2021), no. 4, Paper No. 214, 19 pp.

  8. M. E. Alemdar and O. Duman, General summability methods in the approximation by Bernstein-Chlodovsky operators, Numer. Funct. Anal. Optim. 42 (2021), no. 5, 497-509.

  9. İ. Aslan and O. Duman, Nonlinear approximation in n-dimension with the help of summability methods, Rev. R. Acad. Cienc. Exactas Fis. Nat. Ser. A Mat. RACSAM 115 (2021), no. 3, paper no. 105, 27 pp.

  10. O. Duman, Generalized Cesaro summability of Fourier series and its applications, Constr. Math. Anal. 4 (2021), no. 2, 135-144.

  11. İ. Aslan and O. Duman, Characterization of absolute and uniform continuity, Hacettepe J. Math. Stat. 49 (2020), no. 5, 1550-1565.

  12. O. Ocalan and O. Duman, Solutions to conjectures on a nonlinear recursive equation, Czechoslovak Math. J. 70 (2020), no. 3, 867-880.

  13. T. Y. Gökçer and O. Duman, Approximation by max-min operators: A general theory and its applications, Fuzzy Sets Systems, 394 (2020), 146-161.

  14. C. Turkun and O. Duman, Modified neural network operators and their convergence properties with summability methods, Rev. R. Acad. Cienc. Exactas Fis. Nat. Ser. A Mat. RACSAM 114 (2020), no. 3, paper no. 132, 18 pp.

  15. İ. Aslan and O. Duman, Approximation by nonlinear operators via summability process, Math. Nachr. 293 (2020), no. 3, 430-448.

  16. (Book chapter) O. Duman, Error estimation for approximate solutions of delay Volterra integral equations, in "Frontiers in Functional Equations and Analytic Inequalities", pp. 585-597, Springer Nature, Switzerland, 2019.

  17. İ. Aslan and O. Duman, Summability on Mellin-type nonlinear integral operators, Integral Transform. Spec. Funct. 30 (2019), no. 6, 492-511.

  18. O. Ocalan and O. Duman, On solutions of the recursive equations x_{n+1}=x_{n-1}^{p}/x_{n}^{p} (p>0) via Fibonacci-type sequences, Electron. J. Math. Anal. Appl. 7 (2019), no. 1, 102-115.

  19. C. Turan and O. Duman, Hardy-type Tauberian conditions on time scales, Mediterr. J. Math. 15 (2018), no. 5, Art. 198, 12 pp.

  20. C. Turan and O. Duman, Fundamental properties of statistical convergence and lacunary statistical convergence on time scales, Filomat, 31 (2017), no. 14, 4455-4467.

  21. O. G. Atlihan, M. Unver and O. Duman, Korovkin theorems on weighted spaces: revisited, Periodica Math. Hungar. 75 (2017), no. 2, 201-209.

  22. O. Duman, Singular approximation in polydiscs by summability process, Positivity 20 (2016), no. 3, 663-676.

  23. (Book chapter) T. Y. Gökçer and O. Duman, Summation process by max-product operators, in "Computational Analysis", pp. 59-67, Springer Proceedings in Mathematics & Statistics, Springer, New York, 2016.

  24. (Edited-book) G.A. Anastassiou and O. Duman (eds.), Computational Analysis, Springer Proceedings in Mathematics & Statistics, Springer, New York, 2016, 3396 p. ISBN 978-3-319-28441-5.

  25. İ. Aslan and O. Duman, Summability process on the Baskakov-type approximation, Periodica Math. Hungar. 72 (2016), no. 2, 186-199.

  26. (Book chapter) O. Duman, Nonlinear approximation: q-Bernstein operators of max-product kind, in "Intelligent Mathematics II: Applied Mathematics and Approximation Theory", pp. 33-56, Advances in Intelligent Systems and Computing, Vol. 441, Springer, Heidelberg, 2016.

  27. (Edited-book) G.A. Anastassiou and O. Duman (eds.), Intelligent Mathematics II: Applied Mathematics and Approximation Theory, Advances in Intelligent Systems and Computing, Vol. 441, Springer, Heidelberg, 2016, 502 p. ISBN 978-3-319-30322-2.

  28. M. A. Özarslan and O. Duman, Smoothness properties of modified Bernstein-Kantorovich operators, Numer. Funct. Anal. Optim. 37 (2016), no. 1, 92-105.

  29. N. Küçük and O. Duman, Summability methods in weighted approximation to derivatives of functions, Serdica Math. J. 41 (2015), 355-368.

  30. O. Duman, Summability process by Mastroianni operators and their generalizations, Mediterr. J. Math. 12 (2015), 21-35.

  31. O. Duman, Nonlinear Bernstein-type operators providing a better error estimation, Miskolc. Math. Notes 15 (2014), no. 2, 393-400.

  32. O. Duman, Summability process by singular operators, Publ. Math. Debrecen 85 (2014) 373-386.

  33. (Edited-book) G.A. Anastassiou and O. Duman (eds.), Advances in Applied Mathematics and Approximation Theory, Springer Proceedings in Mathematics & Statistics, Vol. 41, Springer, New York, 2013, 486 pp. ISBN: 978-1-4614-6393-1.

  34. C. Turan and O. Duman, Convergence methods on time scales, AIP Conf. Proc. 1558 (2013) 1120-1123.

  35. (Book chapter) C. Turan and O. Duman, Statistical convergence on time scales and its characterizations, n "Advances in Applied Mathematics and Approximation Theory", pp. 57-71, Springer Proc. Math. Stat., vol. 41, Springer, New York, 2013.

  36. A. A. Ergür and O. Duman, Generalization of statistical Korovkin theorems, J. Appl. Math. 2013, Article ID 187530, 5 pp.

  37. Z. Ünal, M. A. Özarslan and O. Duman, Approximation properties of real and complex Post-Widder operators based on q-integers, Miskolc. Math. Notes 13 (2012) 581-603.

  38. O. Duman and M. Kester, Statistical approximation by double Poisson-Cauchy singular integral operators, Results Math. 62 (2012) 53-65.

  39. A. D. Gadjiev, O. Duman and A. M. Ghorbanalizadeh, Ideal convergence of k-positive linear operators, J. Funct. Spaces Appl. 2012, Article ID 178316, 12 pp.

  40. (Monograph-book) G.A. Anastassiou and O. Duman, Towards Intelligent Modeling: Statistical Approximation Theory, Intelligent Systems Reference Library, Vol. 14, Springer, Berlin, 2011, 234 pp. ISBN: 978-3-642-19825-0.

  41. O. Duman and E. Erkuş-Duman, Statistical Korovkin-type theory for matrix-valued functions, Studia Sci. Math. Hungar. 48 (2011) 489-508.

  42. H. Aktuğlu, M. A. Özarslan and O. Duman, Matrix summability methods on the approximation of multivatiate q-MKZ operators, Bull. Malaysian Math. Sci. Soc. 34 (2011) 465-474.

  43. A. Aral and O. Duman, A Voronovskaya-type formula for SMK operators via statistical convergence, Math. Slovaca 61 (2011) 235-244.

  44. M. Burgin and O. Duman, Approximations by linear operators in spaces of fuzzy continuous functions, Positivity 15 (2011) 57-72.

  45. M. A. Özarslan, O. Duman and N. I. Mahmudov, Local approximation properties of modified Baskakov operators, Results Math. 59 (2011) 1-11.

  46. G. A. Anastassiou and O. Duman, Statistical Lp-convergence of double smooth Picard singular integral operators, J. Comput. Anal. Appl. 13 (2011) 167-187.

  47. O. Duman and M. A. Özarslan, Global approximation results for modified Szasz-Mirakjan operators, Taiwanese J. Math. 15 (2011) 75-86.

  48. G. A. Anastassiou and O. Duman, Statistical approximation by double complex Gauss-Weierstrass integral operators, Appl. Math. Lett. 24 (2011) 438-443.

  49. E. Erkuş-Duman and O. Duman, Statistical approximation properties of high order operators constructed with the Chan-Chyan-Srivastava polynomials, Appl. Math. Comput. 218 (2011) 1927-1933.

  50. M. Burgin and O. Duman, Approximate fuzzy continuity of functions, Internat. J. Fuzzy Syst. Appl. 1 (2011) 37-46.

  51. O. Duman, Statistical fuzzy approximation to fuzzy differentiable functions by fuzzy linear operators, Hacettepe J. Math. Stat. 39 (2010) 497-514.

  52. M. A. Özarslan and O. Duman, Local approximation behavior of modified SMK operators, Miskolc Math. Notes 11 (2010) 87-99.

  53. O. Duman,  Statistical convergence of max-product approximating operators, Turkish J. Math. 34 (2010) 501-514.

  54. F. Dirik, O. Duman and K. Demirci, Approximation in statistical sense to B-continuous functions by positive linear operators, Studia Sci. Math. Hungar. 47 (2010) 289-298.

  55. M. A. Özarslan and O. Duman, Global approximation properties of modified SMK operators, Filomat 24 (2010) 47-61.

  56. S. Karakuş, K. Demirci and O. Duman, Statistical approximation by positive linear operators on modular spaces, Positivity 14 (2010) 312-334.

  57. G. A. Anastassiou and O. Duman, Statistical convergence of double complex Picard integral operators, Appl. Math. Lett. 23 (2010) 852-858.

  58. M. A. Özarslan, O. Duman and C. Kaanoğlu, Rates of convergence of certain King-type operators for functions with derivative of bounded variation, Math. Comput. Modelling 52 (2010) 334-345.

  59. G. A. Anastassiou and O. Duman, Statistical Korovkin theory for multivariate stochastic processes,  Stoch. Anal. Appl. 28 (2010) 648-661.

  60. O. Duman, Fuzzy approximation based on statistical rates, Publ. Math. Debrecen 76 (2010) 453-463.

  61. G. A. Anastassiou and O. Duman, Statistical Lp approximation by double Gauss-Weierstrass singular integral operators, Comput. Math. Appl. 59 (2010) 1985-1999.

  62. O. Duman, M. A. Özarslan and E. Erkuş-Duman, Rates of ideal convergence for approximation operators, Mediterr. J. Math. 7 (2010) 111-121.

  63. O. Duman and M. Gürcan, Some characterizations on statistical convergence of expected values of random variables, J. Math. Anal. 1 (2010) 1-8.

  64. G. A. Anastassiou and O. Duman, Uniform approximation in statistical sense by double Gauss-Weierstrass singular integral operators, Nonlinear Funct. Anal. Appl. 15 (2010) 487-502.

  65. V. Gupta and O. Duman, Bernstein-Durrmeyer type operators preserving linear functions, Mat. Vesnik 62 (2010) 259-264.

  66. G. A. Anastassiou and O. Duman, Fractional trigonometric Korovkin theory in statistical sense, Serdica Math. J. 36 (2010) 121-136.

  67. M. Bohner and O. Duman, Opial-type inequalities for diamond-alpha derivatives and integrals on time scales, Differ. Equ. Dyn. Syst. 18 (2010) 229-237.

  68. G. A. Anastassiou and O. Duman, Statistical approximation by double Picard singular integral operators, Studia Univ. Babes-Bolyai Math. 55 (2010), 3-20.

  69. M. Burgin and O. Duman, Fuzzy approximate continuity, J. Intell. Fuzzy Systems 20 (2009) 225-233.

  70. O. Duman, Strong versions of the theorems of Weierstrass, Montel and Hurwitz, Hacettepe J. Math. Stat. 38 (2009) 153-159.

  71. F. Dirik, O. Duman and K. Demirci, Statistical approximation to Bögel-type continuous and periodic functions, Cent. Eur. J. Math. 7 (2009) 539-549.

  72. O. Duman and H. Merdan, Stability analysis of continuous population model involving predation and Allee effect, Chaos Solitons Fractals 41 (2009) 1218-1222.

  73. M. A. Özarslan and O. Duman, Approximation theorems by Meyer-König and Zeller type operators, Chaos Solitons Fractals 41 (2009) 451-456.

  74. O. Duman, M. A. Özarslan and B. Della Vecchia, Modified Szasz-Mirakjan-Kantorovich operators preserving linear functions, Turkish J. Math. 33 (2009) 151-158.

  75. C. Çelik and O. Duman, Allee effect in a discrete-time predator-prey system, Chaos Solitons Fractals 40 (2009) 1956-1962.

  76. H. Merdan and O. Duman, On the stability analysis of a general discrete-time population model involving predation and Allee effects, Chaos Solitons Fractals 40 (2009) 1169-1175.

  77. G. A. Anastassiou and O. Duman, High order statistical fuzzy Korovkin theory, Stoch. Anal. Appl. 27 (2009) 543-554

  78. H. Merdan, O. Duman, Ö. Akın and C. Çelik, Allee effects on population dynamics in continuous (overlapping) case, Chaos Solitons Fractals 39 (2009) 1994-2001.

  79. G. A. Anastassiou, O. Duman and E. Erkuş-Duman, Statistical approximation for stochastic processes, Stoch. Anal. Appl. 27 (2009) 460-474.

  80. G. A. Anastassiou and O. Duman, Statistical weighted approximation to derivatives of functions by linear operator, J. Comput. Anal. Appl. 11 (2009) 20-30.

  81. Ö. Ocalan and O. Duman, Oscillation analysis of neutral difference equations with delays, Chaos Solitons Fractals 39 (2009) 261-270.

  82. G. A. Anastassiou and O. Duman, On relaxing the positivity condition of linear operators in statistical Korovkin-type approximations, J. Comput. Anal. Appl. 11 (2009) 7-19

  83. G. A. Anastassiou and O. Duman, Fractional Korovkin theory based on statistical convergence, Serdica Mathematical Journal 35 (2009) 381-396

  84. M. A. Özarslan and O. Duman, A new approach in obtaining a better estimation in approximation by positive linear operators, Commun. Fac. Sci. Univ. Ank. Sér. A1 Math. Stat. 58 (2009) 17-22.

  85. G. A. Anastassiou and O. Duman, Statistical approximation to periodic functions by a general class of linear operators, J. Concr. Appl. Math. 7 (2009) 200-207.

  86. M. Burgin and O. Duman,  Properties of fuzzy statistical limits, J. Intell. Fuzzy Systems 19 (2008) 385-392.

  87. M. A. Özarslan and O. Duman, Approximation properties of Poisson integrals for orthogonal expansions, Taiwanese J. Math. 12 (2008) 1147-1163.

  88. M. A. Özarslan, O. Duman and H. M. Srivastava, Statistical approximation results for Kantorovich-type operators involving some special functions, Math. Comput. Modelling 48 (2008) 388-401.

  89. O. Duman, A-Statistical convergence of sequences of convolution operators, Taiwanese J. Math. 12 (2008) 523-536.

  90. M. Burgin and O. Duman, Statistical fuzzy convergence, Internat. J. Uncertain. Fuzziness Knowledge-Based Systems 16 (2008) 879-902.

  91. O. Duman and C. Orhan, Rates of A-statistical convergence of operators in the space of locally integrable functions, Appl. Math. Lett. 21 (2008) 431-435.

  92. C. Çelik, H. Merdan, O. Duman and Ö. Akın, Allee effects on population dynamics with delay, Chaos Solitons Fractals 37 (2008) 65-74.

  93. E. Erkuş-Duman and O. Duman, Integral-type generalizations of operators obtained from certain multivariate polynomials, Calcolo 45 (2008) 53-67.

  94. M. A. Özarslan and O. Duman, Local approximation results for Szasz-Mirakjan type operators, Arch. Math. (Basel) 90 (2008) 144-149.

  95. O. Duman and G. A. Anastassiou, On statistical fuzzy trigonometric Korovkin theory, J. Comput. Anal. Appl. 10 (2008) 333-344.

  96. G. A. Anastassiou and O. Duman, A Baskakov type generalization of statistical Korovkin theory, J. Math. Anal. Appl. 340 (2008) 476-486.

  97. O. Duman, M. A. Özarslan and H. Aktuğlu, Better error estimation for Szasz-Mirakjan-Beta operators, J. Comput. Anal. Appl. 10 (2008) 53-59.

  98. S. Karakuş, K. Demirci and O. Duman, Equi-statistical convergence of positive linear operators, J. Math. Anal. Appl. 339 (2008) 1065-1072.

  99. G. A. Anastassiou and O. Duman, Statistical fuzzy approximation by fuzzy positive linear operators, Comput. Math. Appl. 55 (2008) 573-580.

  100. S. Karakus, K. Demirci and O. Duman, Statistical convergence on intuitionistic fuzzy normed spaces, Chaos Solitons Fractals 35 (2008) 763-769.

  101. O. Duman and M.A. Özarslan, Szasz-Mirakjan type operators providing a better error estimation, Appl. Math. Lett. 20 (2007) 1184-1188.

  102. B. Della Vecchia and O. Duman, Weighted approximation by Meyer-König and Zeller type operators, Studia Sci. Math. Hungar. 44 (2007) 445-467.

  103. M. A. Özarslan and O. Duman, MKZ type operators providing a better estimation on [1/2,1), Canadian Math. Bull. 50 (2007) 434-439.

  104. O. Duman, Regular matrix transformations and rates of convergence of positive linear operators, Calcolo 44 (2007) 159-165.

  105. O. Duman, Korovkin type approximation theorems via I-convergence, Czechoslovak Math. J. 57 (2007) 367-375.

  106. O. Duman, Higher order generalization of positive linear operators defined by a class of Borel measures, Turkish J. Math. 31 (2007) 333-339.

  107. O. Duman and E. Erkuş, Approximation of continuous periodic functions via statistical convergence, Comput. Math. Appl. 52 (2006) 967-974.

  108. E. Erkuş, O. Duman and H. M. Srivastava, Statistical approximation of certain positive linear operators constructed by means of the Chan-Chyan-Srivastava polynomials, Appl. Math. Comput. 182 (2006) 213-222.

  109. O. Duman, E. Erkuş and V. Gupta, Statistical rates on the multivariate approximation theory, Math. Comput. Modelling 44 (2006) 763-770.

  110. O. Duman, Statistical approximation theorems by k-positive linear operators, Arch. Math. (Basel) 86 (2006) 569-576.

  111. O. Duman, M. A. Özarslan and O. Doğru, On integral type generalizations of positive linear operators, Studia Math. 174 (2006) 1-12.

  112. O. Doğru and O. Duman, Statistical approximation of Meyer König and Zeller operators based on q-integers,  Publ. Math. Debrecen 68 (2006) 199-214.

  113. E. Erkuş and O. Duman, A Korovkin type approximation theorem in statistical sense, Studia Sci. Math. Hungar. 43 (2006) 285-294.

  114. O. Duman and C. Orhan, An abstract version of the Korovkin approximation theorem, Publ. Math. Debrecen 69 (2006) 33-46.

  115. M. A. Özarslan, O. Duman and O. Doğru, A-Statistical convergence for a class of positive linear operators, Rev. Anal. Numér. Théor. Approx. 35 (2006) 161-172.

  116. E. Erkuş and O. Duman, A-statistical extension of the Korovkin type approximation theorem, Proc. Indian Acad. Sci. Math. Sci. 115 (2005) 499-508.

  117. M. A. Özarslan, O. Duman and O. Doğru, Rates of A-statistical convergence of approximating operators, Calcolo 42 (2005) 93-104.

  118. O. Duman and C. Orhan, Rates of A-statistical convergence of positive linear operators, Appl. Math. Lett. 18 (2005) 1339-1344.

  119. O. Duman, The effects of matrix summability methods on bounds of function sequences, Appl. Math. Lett. 17 (2004) 1221-1229.

  120. O. Duman and C. Orhan,  Statistical approximation by positive linear operators, Studia Math. 161 (2004) 187-197.

  121. O. Duman and C. Orhan, Mu-Statistically convergent function sequences, Czechoslovak Math. J. 54 (2004) 413-422.

  122. O. Duman and C. Orhan, Statistical approximation in the space of locally integrable function,  Publ. Math. Debrecen 63 (2003) 133-144.

  123. O. Duman, M. K. Khan and C. Orhan, A-statistical convergence of approximatig operators, Math. Inequal. Appl. 6 (2003) 689-699.

  124. O. Doğru, O. Duman and C. Orhan, Statistical approximation by generalized Meyer-König and Zeller type operators, Studia Sci. Math. Hungar. 40 (2003) 359-371.

  125. O. Duman, Statistical approximation for periodic functions, Demonstratio Math. 36 (2003) 873-878.