Arama Sonuçları

Listeleniyor 1 - 9 / 9
  • Yayın
    Harmonic function for which the second dilatation is ?-spiral
    (Springer International Publishing AG, 2012) Aydoğan, Seher Melike; Duman, Emel Yavuz; Polatoğlu, Yaşar; Kahramaner, Yasemin
    Let f = h + (g) over bar be a harmonic function in the unit disc . We will give some properties of f under the condition the second dilatation is alpha-spiral.
  • Yayın
    Some results on a starlike log-harmonic mapping of order alpha
    (Elsevier Science BV, 2014-01-15) Aydoğan, Seher Melike
    Let H(D) be the linear space of all analytic functions defined on the open unit disc D = z is an element of C : vertical bar z vertical bar < 1. A sense preserving log-harmonic mapping is the solution of the non-linear elliptic partial differential equation f(z) = w(z)f(z)(f(z)/f) where w(z) is an element of H (D) is the second dilatation off such that vertical bar w(z)vertical bar < 1 for all z is an element of D.A sense preserving log-harmonic mapping is a solution of the non-linear elliptic partial differential equation fz f((z) over bar)/(f) over bar = w(z).f(z)/f (0.1) where w(z) the second dilatation off and w(z) is an element of H(D), vertical bar w(z)vertical bar < 1 for every z is an element of D. It has been shown that if f is a non-vanishing log-harmonic mapping, then f can be expressed as f(z) = h(z)<(g(z))over bar> (0.2) where h(z) and g(z) are analytic in D with the normalization h(0) not equal 0, g(0) = 1. On the other hand if f vanishes at z = 0, but it is not identically zero, then f admits the following representation f(z) = z.z(2 beta)h(z)<(g(z))over bar> (0.3) where Re beta > -1/2, h(z) and g(z) are analytic in the open disc D with the normalization h(0) not equal 0, g(0) = 1 (Abdulhadi and Bshouty, 1988) [2], (Abdulhadi and Hengartner, 1996) [3].In the present paper, we will give the extent of the idea, which was introduced by Abdulhadi and Bshouty (1988) [2]. One of the interesting applications of this extent idea is an investigation of the subclass of log-harmonic mappings for starlike log-harmonic mappings of order alpha.
  • Yayın
    Some boundary Harnack principles with uniform constants
    (Springer Science and Business Media B.V., 2022-10) Barlow, Martin T.; Karlı, Deniz
    We prove two versions of a boundary Harnack principle in which the constants do not depend on the domain by using probabilistic methods.
  • Yayın
    Quasiconformal harmonic mappings related to Janowski alpha-spirallike functions
    (Amer Inst Physics, 2014) Aydoğan, Seher Melike; Polatoğlu, Yaşar
    Let f = h(z) + g(z) be a univalent sense-preserving harmonic mapping of the open unit disc D = {z/vertical bar z vertical bar < 1}. If f satisfies the condition vertical bar omega(z)vertical bar = vertical bar g'(z)/h'(z)vertical bar < k, 0 < k < 1 the f is called k-quasiconformal harmonic mapping in D. In the present paper we will give some properties of the class of k-quasiconformal mappings related to Janowski alpha-spirallike functions.
  • Yayın
    Subclass of m-quasiconformal harmonic functions in association with Janowski starlike functions
    (Elsevier Science Inc, 2018-02-15) Sakar, Fethiye Müge; Aydoğan, Seher Melike
    Let's take f(z) = h (z) + <(g(z))over bar> which is an univalent sense-preserving harmonic functions in open unit disc D = {z : vertical bar z vertical bar < 1}. If f (z) fulfills vertical bar w(z)vertical bar = |g'(z)/h'(z)vertical bar < m, where 0 <= m < 1, then f(z) is known m-quasiconformal harmonic function in the unit disc (Kalaj, 2010) [8]. This class is represented by S-H(m).The goal of this study is to introduce certain features of the solution for non- linear partial differential equation <(f)over bar>((z) over bar) = w(z)f(z) when vertical bar w(z)vertical bar < m, w(z) (sic) m(2)(b(1)-z)/m(2)-b(1)z, h(z) is an element of S*(A, B). In such case S*(A, B) is known to be the class for Janowski starlike functions. We will investigate growth theorems, distortion theorems, jacobian bounds and coefficient ineqaulities, convex combination and convolution properties for this subclass.
  • Yayın
    Notes on harmonic functions for which the second dilatation is α - spiral
    (Eudoxus Press, 2015-06) Aydoğan, Seher Melike
    In this study, we consider, f = h + (g) over bar harmonic functions in the unit disc D. By applying S. S. Miller and P. M. Mocanu result, we obtain a new subclass of harmonic functions, such as S-HPST*(alpha, beta) We introduce this new class as defined in the following form, S-HPST*(alpha, beta) = {f = h(z) + <(g(z))over bar>vertical bar f is an element of S-H, h(z) is an element of S* , Re (e(i alpha)g '(z)/h '(z)) > beta,vertical bar alpha vertical bar < pi/2,0 <= beta < (0.1), We also use subordination principle, study on distortion theorems, some numerical examples and coefficient inequalities of this class.
  • Yayın
    A certain class of starlike log-harmonic mappings
    (Elsevier Science BV, 2014-11) Aydoğan, Seher Melike; Polatoğlu, Yaşar
    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).
  • Yayın
    Harmonic mappings related to the m-fold starlike functions
    (Elsevier Science Inc, 2015-09-15) Aydoğan, Seher Melike; Polatoğlu, Yaşar; Kahramaner, Yasemin
    In the present paper we will give some properties of the subclass of harmonic mappings which is related to m-fold starlike functions in the open unit disc D = {z parallel to z vertical bar < 1}. Throughout this paper we restrict ourselves to the study of sense-preserving harmonic mappings. We also note that an elegant and complete treatment theory of the harmonic mapping is given in Durens monograph (Duren, 1983). The main aim of us to investigate some properties of the new class of us which represented as in the following form, S*H(m) = {f = h(z) + <(g(z))over bar>vertical bar f is an element of SH(m), g'(z)/h'(z) < b(1)p(z), h(z) is an element of S*(m), p(z) is an element of P-(m)}, where h(z) = z + Sigma(infinity)(n-1) a(mn+1)z(mn+1), g(z) = Sigma(infinity)(n-0) b(mn+1)z(mn+1), vertical bar b(1)vertical bar < 1.
  • Yayın
    Some remarks on uniform boundary Harnack principles
    (Cornell Univ, 2021-03-18) Barlow, Martin T.; Karlı, Deniz
    We prove two versions of a boundary Harnack principle in which the constants do not depend on the domain by using probabilistic methods.