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Publication Embargo Close-to-convex functions defined by fractional operator(2013) Aydoğan, Seher Melike; Kahramaner, Yasemin; POLATOĞLU, YAŞAR; 35549; 8366; 199370Let S denote the class of functions f(z) = z + a2z2 + ... analytic and univalent in the open unit disc D = {z ∈ CPublication Embargo A Characterization for Convex Functions of Complex Order b(İstanbul University Science Faculty, 1997) POLATOĞLU, YAŞAR; 199370The 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 convex functions of complex order b.Publication Embargo On generalized Janowski starlike logharmonic(2011) Mohd, Maisarah Haji; Darus, Maslina; Yavuz Duman, Emel; POLATOĞLU, YAŞAR; 199370; 111202In 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 Janowski starlike defined by subordination. Further we obtain the bound for the functional h(z)/g(z) for f in this class.Publication Embargo The radius of starlikeness of the certain classes of p-valent functions defined by multiplier transformations(Springer International Publishing, 2008-12) Acu, Mugur; YAVUZ, EMEL; POLATOĞLU, YAŞAR; 199370; 111202The aim of this paper is to give the radius of starlikeness of the certain classes of Open image in new window-valent functions defined by multiplier transformations. The results are obtained by using techniques of Robertson (1953,1963) which was used by Bernardi (1970), Libera (1971), Livingstone (1966), and Goel (1972).Publication Embargo Multivalued starlike functions of complex order(2008) Çağlar, Mert; Owa, Shigeyoshi; YAVUZ, EMEL; POLATOĞLU, YAŞAR; 199370; 111202Let 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 ∈ CPublication Embargo Lambda-fractional properties of generalized Janowski functions in the unit disc(2008) Çağlar, Mert; YAVUZ, EMEL; POLATOĞLU, YAŞAR; 108339; 108339; 111202For analytic function f(z) = z + a2z 2 + · · · in the open unit disc D, a new fractional operator Dλf(z) is defined. Applying this fractional operator Dλf(z) and the principle of subordination, we give new proofs for some classical results concerning the class S ∗ λ (A, B, α) of functions f(z).Publication Embargo Growth and distortion theorems for multivalent Janowski close-to-convex harmonic functions with shear construction method(Scientific Technical Research Council Turkey-Tubitak, Ataturk Bulvarı No 221, Kavaklıdere, Tr-06100 Ankara, Turkey, 2013) Yavuz Duman, Emel; Ozkan, Hatice Esra; POLATOĞLU, YAŞAR; 199370; 111202In this paper we introduce the class of m-valent 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.Publication Embargo Schwarzian Derivative Revisited(İstanbul Kültür Üniversitesi Yayınları, 2006-12) Çağlar, Mert; Demirer, R. Murat; POLATOĞLU, YAŞAR; TR199370The Boolean-algebraic structure of the so-called Schwarzian derivative is investigated. A sufficient condition for a function of several variables to behave chaotically, which concerns its associated Schwarzian derivative, is also given.Publication Embargo Two points-distortion theorems for multivalued starlike functions(2008) Owa, Shigeyoshi; Nakamura, Yayoi; YAVUZ, EMEL; POLATOĞLU, YAŞAR; 199370; 111202Let A be the class of 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, the fractional operator Dλf(z) is defined. Further, a new subclass S∗ λ of A is considered using the fractional operator Dλf(z). The object of the present paper is to consider some properties of f(z) in the class S∗ λ.Publication Embargo On Janowski starlike functions(Springer International Publishing Ag, Gewerbestrasse 11, Cham, Ch-6330, Switzerland, 2007) Çağlar, Mert; Şen, A.; Owa, Shigeyoshi; YAVUZ, EMEL; POLATOĞLU, YAŞAR; 108339; 199370; 111202For 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) consisting of f(z) associated with Janowski function is defined. The objective of the present paper is to discuss some interesting properties of the class F-lambda(*)(A, B). Copyright (c) 2007.