Browsing by Author "Yavuz Duman, Emel"
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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, 201405)Let V(k) be the class of functions with bounded boundary rotation and let SH be the class of sensepreserving harmonic mappings. In the present paper we investigate a certain class of harmonic mappings related to the ... 
A Remark on multivalently convex and starlike functions
Nunokawa, Mamoru; Owa, Shigeyoshi; Polatoğlu, Yaşar; Yavuz Duman, Emel (200701)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. 
An investigation on a new class of harmonic mappings
Yavuz Duman, Emel; Polatoğlu, Yaşar; Kahramaner, Yasemin (Springer International Publishing Ag, Gewerbestrasse 11, Cham, Ch6330, Switzerland, 2013)In the present paper, we give an extension of the idea which was introduced by Sakaguchi (J. Math. Soc. Jpn. 11:7275, 1959), and we give some applications of this extended idea for the investigation of the class of harmonic ... 
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 ... 
Application of the subordination principle to the multivalent harmonic mappings with shear construction method
Polatoğlu, Yaşar; Yavuz Duman, Emel; Özkan, H. Esra (201106)The harmonic function in the open unit disc D = (z is an element of C vertical bar z vertical bar < 1} can be written as a sum of an analytic and an antianalytic function. f = h(z) + g(z), where h(z) and g(z) are analytic ... 
Coefficient Inequality For Perturbed Harmonic Mappings
Polatoğlu, Yaşar; Çağlar, Mert; Yavuz Duman, Emel (PergamonElsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford Ox5 1Gb, England, 201008)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. 
Distortion estimate and radius of starlikeness for generalized pvalent closetostar functions
Özkan, H. Esra; Yavuz Duman, Emel (HIKARI, 2013)Let A(p, n), n ≥ 1, p ≥ 1 be the class of all analytic functions in the open unit disc D = {z z < 1} of the form f(z) = zp + anp+1znp+1 + anp+2znp+2 + ··· . Let g(z) be an element of A(p, n) such that g(z) satisfies ... 
Distortion properties of perturbed mvalent Janowski Starlike logharmonic functions
Polatoğlu, Yaşar; Özkan, H. Esra; Yavuz Duman, Emel (International Conference on Theory and Applications of Mathematics and Informatics, ICTAMI, 2009) 
Growth and distortion theorems for multivalent Janowski closetoconvex harmonic functions with shear construction method
Polatoğlu, Yaşar; Yavuz Duman, Emel; Ozkan, Hatice Esra (Scientific Technical Research Council TurkeyTubitak, Ataturk Bulvarı No 221, Kavaklıdere, Tr06100 Ankara, Turkey, 2013)In this paper we introduce the class of mvalent Janowski close to convex harmonic functions. Growth and distortion theorems are obtained for this class. Our study is based on the harmonic shear methods for harmonic functions. 
Growth theorems for perturbated starlike logharmonic mappings of complex order
Polatoğlu, Yaşar; Yavuz Duman, Emel; Özkan, H. Esra (2009)Let H(D) be the linear space of all analytic functions defined on the open unit disc D = {z ∈ C : z < 1}. A sensepreserving logharmonic mapping is the solution of the nonlinear elliptic partial differential equation ... 
Harmonic mappings for which second dilatation is Janowski functions
Yavuz Duman, Emel; Polatoğlu, Yaşar; Kahramaner, Yasemin; Darus, Maslina (2013)In the present paper we extend the fundamental property that if h(z) and g(z) are regular functions in the open unit disc D with the properties h(0) = g(0) = 0, h maps D onto manysheeted region which is starlike with ... 
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 Harmonic Starlike Mappings
Yavuz Duman, Emel; Owa, Shigeyoshi (9th International Symposium on Geometric Function Theory and Applications, GFTA, 2014) 
Notes on Starlike logHarmonic Functions of Order alpha
Aydoğan, Seher Melike; Yavuz Duman, Emel; Owa, Shigeyoshi (2013)For logharmonic 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 logharmonic functions of order α (0 ≤ α < 1) are considered. The object ... 
On a subclass of harmonic mappings
Yavuz Duman, Emel; Kahramaner, Yasemin; Polatoğlu, Yaşar (2013)In the present paper we extent the fundamental property that if h(z) and g(z) are regular functions in the open unit disc D with the properties h(0) = g(0) = 0, h(z) maps D onto λspiral region and Ren e iλ ... 
On generalized Janowski starlike logharmonic
Mohd, Maisarah Haji; Darus, Maslina; Polatoğlu, Yaşar; Yavuz Duman, Emel (2011)In this paper, we consider univalent logharmonic mappings of the form f(z) = zh(z)g(z) defined on the open unit disc with the normalization condition g(0) = 1 and h(0) 6= 0. We investigate the class of generalized ... 
On subclass of multivalent closetoconvex harmonic functions
Polatoğlu, Yaşar; Yavuz Duman, Emel; Özkan, H. Esra (2009) 
On the improvement of Mocanu's conditions
Nunokawa, M.; Owa, Shigeyoshi; Cho, N. E.; Sokół, J.; Yavuz Duman, Emel (Springer International Publishing, 201312)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), ...