Борислав Радков Драганов

Борислав Радков Драганов

Доцент
Доктор
Имейл: 
bdraganov(at)fmi.uni-sofia.bg
Телефон: 
02/8161-766
Кабинет: 
ФМИ-211
Приемно време: 

сряда 15 – 17; петък 15 –17
или по предварителна уговорка

Образование и научни степени

  • 2004: доктор, СУ "Св. Кл. Охридски", ФМИ
  • 1998: магистър специалност математика, СУ "Св. Кл. Охридски", ФМИ
  • 1993: Първа английска езикова гимназия, гр. София

Научни интереси

  • Теория на апроксимациите
  • Функционален анализ
  • Хармоничен анализ

Преподавателска дейност

  • Математически анализ на функции на една променлива, спец. Физика, Квантова и космическа теоретична физика, Физика и математика
  • Математически анализ на функции на много променливи, спец. Физика, Квантова и космическа теоретична физика, Физика и математика
  • Theory of Extremal Problems/Теория на екстремалните задачи
  • Теория на мярката и интеграла (интеграл на Лебег)

Списък с публикации

  1. A new modulus of smoothness for trigonometric polynomial approximation, East J. Approx. 8 (2002), 4, 465-499 (pdf).
  2. A new modulus of smoothness for trigonometric polynomial approximation,  Constructive Theory of Functions, Varna, 2002. Proc. Ed. B. Bojanov, Darba, Sofia, 2003, 245-250 (pdf).
  3. The trigonometric analogue of the Taylor's formula and its application, Annuaire Univ. Sofia Fac. Math. Inform.  96 (2004), 141-154 (pdf).
  4. (with Kamen G. Ivanov) A new characterization of weighted Peetre K-functionals, Constr. Approx. 21 (2005), 113-148 (pdf, original publication available at Springer http://www.springerlink.com/).
  5. (with Kamen G. Ivanov) A Characterization of Weighted Lp Approximations by the Gamma and the Post-Widder Operators, Proc. intern. conf. "Constructive Theory of Functions, Varna 2005'', Ed. B. Bojanov, Marin Drinov Academic Publishing House, Sofia, 2006, 80-87 (pdf).
  6. (with Kamen G. Ivanov) Characterizations of Weighted K-Functionals and Their Application, Proc. intern. conf. "Constructive Theory of Functions, Varna 2005'', Ed. B. Bojanov, Marin Drinov Academic Publishing House, Sofia, 2006, 88-97 (pdf).
  7. (with Kamen G. Ivanov) A new characterization of weighted Peetre K-functionals (II), Serdica Math. J. 33 (2007), 59-124 (pdf).
  8. (with Kamen G. Ivanov) A characterization of weighted approximations by the Post-Widder and the Gamma operators, J. Approx. Theory 146 (2007), 3-27 (preprintoriginal publication available at Elsevier).
  9. (with Kamen G. Ivanov) Equivalence between K-functionals based on continuous linear transforms, Serdica Math. J. 33 (2007), 475-494 (pdf).
  10. Simultaneous approximation of functions by Fejér-type operators in a generalized Hölder norm, East J. Approx. 14 (2008), 439-449 (pdf).
  11. Exact estimates of the rate of approximation of convolution operators, J. Approx. Theory 162 (2010), 952-979 (preprint, original publication available at Elsevier).
  12. (with Kamen G. Ivanov) A Characterization of Weighted Approximations by the Post-Widder and the Gamma Operators (II), J. Approx. Theory 162 (2010), 1805-1851 (preprint, original publication available at Elsevier).
  13. On the approximation by convolution operators in homogeneous Banach spaces of periodic functions, Math. Balkanica 25 (2011), 39-59 (pdf).
  14. (with Parvan E. Parvanov) On estimating the rate of best trigonometric approximation by a modulus of smoothness, Acta Math. Hungar. 131 (2011),  360-379 (pdf, original publication available at Springer http://www.springerlink.com/).
  15. Estimating the rate of best trigonometric approximation in homogeneous Banach spaces by moduli of smoothness, Proc. intern. conf. "Constructive Theory of Functions", Sozopol 2010: In Memory of Borislav Bojanov, Eds. G. Nikolov and R. Uluchev, Marin Drinov Academic Publishing House, Sofia, 2012, 80-92 (pdf).
  16. An improved Jackson inequality for best trigonometric approximation, Ukr. Mat. Zhurn.  65 (2013), 1219-1226 and Ukrainian Math. J. 65 (2014), 1354-1362 (pdf, the final publication is available at link.springer.com); a preprint: A sharp Jackson inequality for best trigonometric approximation, CRM Preprint Series 1101, 2012 (available at CRM http://www.crm.cat).

  17. Upper estimates of the approximation rate of combinations of iterates of the Bernstein operator, Annuaire Univ. Sofia Fac. Math. Inform. 101 (2013), 95-104 (pdf).
  18. (with Kamen G. Ivanov)A generalized modulus of smoothness, Proc. Amer. Math. Soc. 142 (2014), 1577-1590.  
  19. On simultaneous approximation by iterated Boolean sums of Bernstein operators, Results Math. 66 (2014), 21-41 (read-only pdf at Springer Nature SharedIt, pdf, the final publication is available at link.springer.com). 
  20. (with Kamen G. Ivanov)Natural weights for uniform approximation by the Szasz-Mirakjan operator,  Proc. intern. conf. "Constructive Theory of Functions", Sozopol 2013: Dedicated to Blagovest Sendov and to the memory of Vasil Popov, Eds. Kamen Ivanov, Geno Nikolov and Rumen Uluchev, Prof. Marin Drinov Academic Publishing House, Sofia, 2014, 57-82 (pdf).
  21. On the approximation by convolution operators in homogeneous Banach spaces on R^d, Math. Balkanica 28 (2014), 9-36 (pdf)
  22. Strong estimates of the weighted simultaneous approximation by the Bernstein and Kantorovich operators and their iterated Boolean sums, J. Approx. Theory  200 (2015), 92–135.