Now showing items 1-20 of 22

    • A note on certain analytic functions 

      Nunokawa, M.; Owa, Shigeyoshi; Polatoğlu, Yaşar (International Short Joint Research Workshop, Study on Calculus Operators in Univalent Function Theory, 2007, Research Institute for Mathematical Sciences, Kyoto University (RIMS), Kyoto, Japan, 2007)
    • A Remark on multivalently convex and starlike functions 

      Nunokawa, Mamoru; Owa, Shigeyoshi; Polatoğlu, Yaşar; Yavuz Duman, Emel (2007-01)
      Applying the result for certain analytic functions due to M. Nunokawa [Proc. Japan Acad. 68A, 152–153 (1992; Zbl 0773.30020)], some properties for multivalently convex and starlike functions ar discussed.
    • Coefficient inequalities for classes of uniformly starlike and convex functions 

      Owa, Shigeyoshi; Polatoğlu, Yaşar; Yavuz, Emel (2006-01)
      In view of classes of uniformly starlike and convex functions in the open unit discUwhich was considered by S. Shams, S.R. Kulkarni and J.M. Jahangiri, some coefficient in-equalities for functions are discussed
    • Multivalued p-valent starlike functions 

      Çağlar, M.; Polatoğlu, Yaşar; Şen, A.; Yavuz, Emel; Owa, Shigeyoshi (2007)
    • Multivalued starlike functions of complex order 

      Polatoğlu, Yaşar; Çağlar, Mert; Owa, Shigeyoshi; Yavuz, Emel; Şen, Arzu (2008)
      Let Aα be the class of functions f(z) = z α (z + a2z 2 + · · ·) which are analytic in the open unit disc U. For f(z) ∈ Aα using the fractional calculus, a subclass S ∗ α (1−b) which is the class of starlike functions ...
    • Multivalued starlike functions of complex order 

      Polatoğlu, Yaşar; Yavuz, Emel; Çağlar, Mert; Owa, Shigeyoshi (2008)
      Let S ∗ λ (1−b)(b 6= 0, complex) denote the class of functions f(z) = z+a2z 2+· · · analytic in the open unit disc D = {z ∈ C||z| < 1} which satisfy for z = reiθ ∈ D, f(z) z 6= 0 and Re · 1 + 1 b µ z (Dλ f ...
    • New characterization of the class of starlike functions 

      Yavuz, Emel; Polatoğlu, Yaşar; Owa, Shigeyoshi (The Korean Mathematical Society, 2008)
      For analytic functions f(z) in the open unit disc D, an operator Nα(f(z)) relating with starlike functions is introduced. The object of the present paper is to discuss some properties of the operator Nα(f(z)).
    • New subclasses of certain analytic functions 

      Owa, Shigeyoshi; Polatoğlu, Yaşar; Yavuz Duman, Emel; Aydoğan, S. M. (2010)
      For certain analytic functions fiz) in the open unit disk U, two subclasses 7ia,S;g) and Q(a,(5;g) associated with some analytic function g{z). Some interesting sufficient conditions for fiz) to be in ^(Q,^;^ ) and ...
    • Notes on certain analytic functions 

      Yavuz, Emel; Owa, Shigeyoshi (SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, ATATURK BULVARI NO 221, KAVAKLIDERE, TR-06100 ANKARA, TURKEY, 2019)
      Let A(n) be the class of functions f(z) = a(n)z(n) + a(n+1)z(n+1) +...(n is an element of N), which are analytic in the open unit disk U, where a(n) not equal 0. For f(z) is an element of A(n), Miller and Mocanu ...
    • Notes on Certain Harmonic Starlike Mappings 

      Yavuz Duman, Emel; Owa, Shigeyoshi (9th International Symposium on Geometric Function Theory and Applications, GFTA, 2014)
    • Notes on Starlike log-Harmonic Functions of Order alpha 

      Aydoğan, Seher Melike; Yavuz Duman, Emel; Owa, Shigeyoshi (2013)
      For log-harmonic functions f(z) = zh(z)g(z) in the open unit disk U, two subclasses H∗ LH(α) and G∗ LH (α) of S∗ LH(α) consisting of all starlike log-harmonic functions of order α (0 ≤ α < 1) are considered. The object ...
    • On Janowski starlike functions 

      Çağlar, Mert; Polatoğlu, Yaşar; Şen, A.; Yavuz, Emel; Owa, Shigeyoshi (Springer International Publishing Ag, Gewerbestrasse 11, Cham, Ch-6330, Switzerland, 2007)
      For analytic functions f(z) in the open unit disc U with f(0) = 0 and f'(0) = 1, applying the fractional calculus for f(z), a new fractional operator D-lambda f(z) is introduced. Further, a new subclass F-lambda(*)(A, B) ...
    • On lambda-fractional convex functions 

      Polatoğlu, Yaşar; Yavuz, Emel; Owa, Shigeyoshi (2007)
    • On some alpha-convex functions 

      Owa, Shigeyoshi; Polatoğlu, Yaşar; Yavuz, Emel; Acu, Mugur; Al-Oboudi, Fatima; Darus, Maslina (2008-06)
      In this paper, we define a general class of α-convex functions, denoted by MLβ,α(q), with respect to a convex domain D (q(z) ∈ Hu(U), q(0) = 1 , q(U) = D) contained in the right half plane by using the linear operator ...
    • On the improvement of Mocanu's conditions 

      Nunokawa, M.; Owa, Shigeyoshi; Cho, N. E.; Sokół, J.; Yavuz Duman, Emel (Springer International Publishing, 2013-12)
      We estimate |Arg{p(z)}| for functions of the form p(z)=1+a1z+a2z2+a3z3+⋯ in the unit disc D={z:|z|<1} under several assumptions. By using Nunokawa’s lemma, we improve a few of Mocanu’s results obtained by differential ...
    • Partial sums of certain univalent functions 

      Hayami, Toshio; Kuroki, Kazuo; Yavuz Duman, Emel; Owa, Shigeyoshi (2012)
      The partial sums f3(z) of some extermal functions for various classes S∗, K and R of starlike functions, convex functions and functions with positive real part in the open unit disk U, respectively, are discussed. In ...
    • Properties of functions concerned with Caratheodory functions 

      Nunokawa, Mamoru; Yavuz Duman, Emel; Owa, Shigeyoshi (2013)
      Let Pn denote the class of analytic functions p(z) of the form p(z) = 1+ cnzn + cn+1zn+1 + ... in the open unit disc U. Applying the result by S. S. Miller and P. T. Mocanu (J. Math. Anal. Appl. 65 (1978), 289–305), ...
    • Reciprocal Classes Of P-Valently Spirallike And P-Valently Robertson Functions 

      Polatoğlu, Yaşar; Uyanık, Neslihan; Owa, Shigeyoshi; Shiraishi, Hitoshi (Springer International Publishing Ag, Gewerbestrasse 11, Cham, Ch-6330, Switzerland, 2011)
      For p-valently spirallike and p-valently Robertson functions in the open unit disk U, reciprocal classes S-p(alpha, beta), and C-p(alpha, beta) are introduced. The object of the present paper is to discuss some interesting ...
    • Some Properties Of Analytic Functions Relating To The Miller And Mocanu Result 

      Yavuz Duman, Emel; Nunokawa, Mamoru; Owa, Shigeyoshi; Aydoğan, Melike (Pergamon-Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford Ox5 1Gb, England, 2011-03)
      Let P(alpha) be the class of analytic functions p(z) in the open unit disc U with p(0) = 1 and |arg p(z)| < pi/2 alpha (z is an element of U) for some real alpha > 0. The object of the present paper is to discuss some ...
    • Some properties of certain analytic functions 

      Owa, Shigeyoshi; Yavuz Duman, Emel (2012)
      Applying the subordinations for analytic functions f(z) normalized by f(0) = 0 and f 0 (0) = 1 in the open unit disk U, some properties of f(z) are discussed.