Now showing items 1-20 of 91

    • A Certain Class of Harmonic Mappings Related to Functions of Bounded Boundary Rotation 

      Polatoğlu, Yaşar; Yavuz Duman, Emel; Aydoğan, Melike (Eudoxus Press, Llc, 1424 Beaver Trail Drive, Cordova, Tn 38016 Usa, 2014-05)
      Let V(k) be the class of functions with bounded boundary rotation and let S-H be the class of sense-preserving harmonic mappings. In the present paper we investigate a certain class of harmonic mappings related to the ...
    • A certain class of starlike log-harmonic mappings 

      Aydoğan, Melike; Polatoğlu, Yaşar (Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2014-11)
      In this paper we investigate some properties of log-harmonic starlike mappings. For this aim we use the subordination principle or Lindelof Principle (Lewandowski (1961) [71). (C) 2014 Elsevier B.V. All rights reserved.
    • A Characterization for Convex Functions of Complex Order b 

      Polatoğlu, Yaşar (İstanbul University Science Faculty, 1997)
      The main purpose of this note is tö give a new characterization for convex functions of complex order b. It should be noticed that by giving specific values to b we obtain new characterizations of important subclasses of ...
    • A Coefficient Inequality for Convex Functions 

      Polatoğlu, Yaşar (İstanbul Kültür Üniversitesi Yayınları, 2002-04)
      Biz bu makalede ' A characterization for convex functions of complex order (Ist. Üniv. Fen Fak. Matematik Dergisi cilt 54 sayfa 175-170, 1997) adlı makalenin çok önemli bir neticesi olan katsayı eşitsizliğini veririz.
    • 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.
    • A study on the generalization of Janowski functions in the unit disc 

      Polatoğlu, Yaşar; Yavuz, Emel; Bolcal, Metin; Şen, A. (2006-01)
      Let › be the class of functions w(z), w(0) = 0, |w(z)| < 1 regular in the unit disc D = {z : |z| < 1}. For arbitrarily fixed numbers A 2 (¡1,1), B 2 (¡1,A), 0 • fi < 1 let P(A,B,fi) be the class of regular functions p(z) ...
    • An investigation of the certain class of multivalent harmonic mappings 

      Polatoğlu, Yaşar; Özkan Uçar, Hatice Esra; Aydoğan, Seher Melike (2016)
      The main purpose of the present paper is to investigate some properties of the certain class of sense-preserving p-valent harmonic mappings in the open unit disc D = {z is an element of C parallel to z vertical bar < 1}.
    • An investigation on a new class of harmonic mappings 

      Yavuz Duman, Emel; Polatoğlu, Yaşar; Kahramaner, Yasemin (Springer International Publishing Ag, Gewerbestrasse 11, Cham, Ch-6330, Switzerland, 2013)
      In the present paper, we give an extension of the idea which was introduced by Sakaguchi (J. Math. Soc. Jpn. 11:72-75, 1959), and we give some applications of this extended idea for the investigation of the class of harmonic ...
    • An investigation on a subclass of p-valently starlike functions in the unit disc 

      Polatoğlu, Yaşar; Bolcal, A.; Şen, A.; Yavuz, Emel (SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, ATATURK BULVARI NO 221, KAVAKLIDERE, TR-06100 ANKARA, TURKEY, 2007)
      Let A(p) denote the class of functions of the form f(z) = z(p) +a(p+1)z(p+1)+a(p+2)z(p+2) +... which are regular and p-valent in the open unit disc D = {z : vertical bar z vertical bar < 1}. Let M-p(alpha) be the subclass ...
    • An Investigation on the Janowski Convex Function of Complex Order 

      Polatoğlu, Yaşar; Bolcal, Metin (İstanbul Kültür Üniversitesi Yayınları, 2003-03)
      Bu makalede kompleks mertebeden Janowski konveks fonksiyonları için bazı neticeler veririz.
    • Analyzing the Chaotic Behaviour of the Harmonic Function of Henon-Heiles Potential 

      Bolcal, Ertuğrul Cem; Karakuş, Cahit; Polatoğlu, Yaşar (Springer-Verlag Berlin, Heidelberger Platz 3, D-14197 Berlin, Germany, 2012-05)
      In this work, the chaotic behaviour of Harmonic function of Henon-Heiles Hamiltonian system is computed and analyzed by using multi-dimensional Schwarzian derivative. Moreover, chaotic behaviour of the saddle points in ...
    • Application Of The Subordination Principle To The Harmonic Mappings Convex In One Direction With Shear Construction Method 

      Polatoğlu, Yaşar; Özkan, Hatice Esra; Yavuz Duman, Emel (Hindawi Publishing Corporation, 410 Park Avenue, 15Th Floor, #287 Pmb, New York, Ny 10022 Usa, 2010)
      Any harmonic function in the open unit disc D = {z vertical bar vertical bar z vertical bar < 1} can be written as a sum of an analytic and antianalytic functions f = h(z) + <(g(z))over bar>, where h(z) and g(z) are analytic ...
    • Bifurcations of Fibonacci generating functions 

      Özer, Mehmet; Cenys, Antanas; Polatoğlu, Yaşar; Hacıbekiroğlu, Gürsel; Akat, Ercüment; Valaristos, A.; Anagnostopoulos, A. N. (PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND, 2007-08)
      In this work the dynamic behaviour of the one-dimensional family of maps F-p,F-q(x) = 1/(1 - px - qx(2)) is examined, for specific values of the control parameters p and q. Lyapunov exponents and bifurcation diagrams are ...
    • Bounded Log-Harmonic Functions with Positive Real Part 

      Özkan Uçar, Hatice Esra; Polatoğlu, Yaşar (Academic Press inc Elsevier Science, 525 B St, Ste 1900, San Diego, Ca 92101-4495 USA, 2013-03-01)
      Let H(D) be the linear space of all analytic functions defined on the open unit disc D = {z vertical bar vertical bar z vertical bar < 1}, and let B be the set of all functions w(z) is an element of H(D) such that vertical ...
    • Certain subclasses of starlike and convex functions of complex order 

      Ravichandran, V.; Polatoğlu, Yaşar; Bolcal, Metin; Yemişci, Halime Arzu (2005)
      In the present investigation, we consider certain subclasses of starlike and convex functions of complex order, giving necessary and sufficient conditions for functions to belong to these classes.
    • Close-to-convex functions defined by fractional operator 

      Aydoğan, Seher Melike; Kahramaner, Yasemin; Polatoğlu, Yaşar (2013)
      Let S denote the class of functions f(z) = z + a2z2 + ... analytic and univalent in the open unit disc D = {z ∈ C||z| < 1}. Consider the subclass and S∗ of S, which are the classes of convex and starlike functions, ...
    • 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
    • Coefficient Inequality For Perturbed Harmonic Mappings 

      Polatoğlu, Yaşar; Çağlar, Mert; Yavuz Duman, Emel (Pergamon-Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford Ox5 1Gb, England, 2010-08)
      The aim of this work is to give the coefficient inequality for the perturbed harmonic mappings in the open unit disc D. (c) 2010 Elsevier Ltd. All rights reserved.