Person: YALÇIN TOKGÖZ, SİBEL
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YALÇIN TOKGÖZ
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SİBEL
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Publication Close-to-convexity of q -bessel-wright functions(Mdpi, 2022-09-01) Din, Muhey U.; Raza, Mohsan; Xin, Qin; Yalçın, Sibel; Malik, Sarfraz Nawaz; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-0243-8263; AAE-9745-2020In this paper, we aim to find sufficient conditions for the close-to-convexity of q-Bessel-Wright functions with respect to starlike functions, such as z/1-z, z/1-z(2), and - log(1 - z) are in the open unit disc. Some consequences related to our main results are also included.Publication Coefficient estimates for certain subclasses of analytic functions defined by new operator(Amer Inst Physics, 2021-01-01) Cakalli, H; Kocinac, LDR; Ashyralyev, A; Harte, R; Dik, M; Canak, I; Kandemir, HS; Tez, M; Gurtug, O; Savas, E; Akay, KU; Ucgun, FC; Uyaver, S; Ashyralyyev, C; Sezer, SA; Turkoglu, AD; Onvural, OR; Sahin, H; Bayram, Hasan; BAYRAM, HASAN; Yalcin, Sibel; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; Cakalli, H; Kocinac, LDR; Ashyralyev, A; Harte, R; Dik, M; Canak, I; Kandemir, HS; Tez, M; Gurtug, O; Savas, E; Akay, KU; Ucgun, FC; Uyaver, S; Ashyralyyev, C; Sezer, SA; Turkoglu, AD; Onvural, OR; Sahin, H; 0000-0001-8106-6834; 0000-0002-0243-8263; B-1379-2014; AAE-9745-2020In this paper, we investigate certain subclasses of analytic functions defined by generalized differential operators involving binomial series. Also, we obtain coefficient estimates involving of the nonhomogeneous Cauchy-Euler differential equation of order r.Publication A subclass of bi-univalent functions based on the faber polynomial expansions and the fibonacci numbers(Mdpi, 2019-02-01) Altınkaya, Şahsene; Yalçın, Sibel; Çakmak, Serkan; ALTINKAYA, ŞAHSENE; YALÇIN TOKGÖZ, SİBEL; Çakmak, Serkan; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-7950-8450; 0000-0002-0243-8263; 0000-0003-0368-7672; AAE-9745-2020; ABC-6175-2020; GZG-2072-2022; AAA-8330-2021In this investigation, by using the Komatu integral operator, we introduce the new class ( pound eta,rho)(Sigma,t)((rho) over tilde of bi-univalent functions based on the rule of subordination. Moreover, we use the Faber polynomial expansions and Fibonacci numbers to derive bounds for the general coefficient vertical bar a(n)vertical bar of the bi-univalent function class.Publication Some properties associated to a certain class of starlike functions(Walter, 2019-12-01) Masih, Vali Soltani; Ebadian, Ali; Yalçın, Sibel; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-0243-8263; AAE-9745-2020; ABC-6175-2020Let A denote the family of analytic functions f with f(0) = f'(0) - 1 = 0, in the open unit disk Delta. We consider a classS-cs(*)(alpha) := {f is an element of A : (zf'(z)/f(z) -1) (sic) z/1+(alpha-1)z-alpha z(2) , z is an element of Delta},where 0 <= alpha <= 1/2, and (sic) is the subordination relation. The methods and techniques of geometric function theory are used to get characteristics of the functions in this class. Further, the sharp inequality for the logarithmic coefficients gamma(n) of f is an element of S-cs(*)(alpha):Sigma(infinity)(n=1) vertical bar gamma n vertical bar(2) <= 1/4(1+alpha)(2) (pi(2)/6 - 2Li(2) (-alpha)+Li-2 (alpha(2))),where Li-2 denotes the dilogarithm function are investigated.Publication The (p, q)-chebyshev polynomial bounds of a general bi-univalent function class(Springer, 2020-07-01) Altinkaya, Sahsene; ALTINKAYA, ŞAHSENE; Yalcin, Sibel; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; 0000-0002-7950-8450; 0000-0002-0243-8263; AAA-8330-2021; AAE-9745-2020In the present paper, we will define the bi-univalent function class S.,mu S ( p, q) related to the ( p, q)-Chebyshev polynomials. Then we will derive the ( p, q)-Chebyshev polynomial bounds for the initial coefficients and determine Fekete-Szego functional for f. S.,mu S ( p, q).Publication Some applications of generalized srivastava-attiya operator to the bi-concave functions(Univ Miskolc Inst Math, 2020-01-01) Altınkaya, Şahsene; Yalçın, Sibel; ALTINKAYA, ŞAHSENE; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-7950-8450; 0000-0002-0243-8263; AAE-9745-2020; AAA-8330-2021In this present investigation, we are concerned with the class Omega C-m,k(Sigma;mu,b)0(alpha) of bi-concave functions defined by using the generalized Srivastava-Attiya operator. Moreover, we derive some coefficient inequalities for functions in this class.Publication On a new class of analytic functions related to fractional calculus(Publ House Bulgarian Acad Sci, 2020-01-01) Owa, Shigeyoshi; Altınkaya, Şahsene; ALTINKAYA, ŞAHSENE; Yalçın, Sibel; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; 0000-0002-7950-8450; 0000-0002-0243-8263; AAA-8330-2021; AAE-9745-2020Let A be the class of analytic functions f with f(0) = 0 and f'(0) = 1 in the open unit disk U. Applying the fractional derivative D-z(lambda) f of order lambda for f is an element of A, a new subclass A(alpha, beta; lambda) of A with 0 <= alpha < 1, beta > 1 and 0 <= lambda < 1 is considered. The object of the present paper is to discuss some interesting properties of this class of functions.Publication The fekete-szego problem for a general class of bi-univalent functions satisfying subordinate conditions(Univ Maragheh, 2017-12-01) Altınkaya, Şahsene; Yalçın, Sibel; ALTINKAYA, ŞAHSENE; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-0243-8263; AAE-9745-2020; AAA-8330-2021In this work, we obtain the Fekete-Szego inequalities for the class P-Sigma (lambda, phi) of bi-univalent functions. The results presented in this paper improve the recent work of Prema and Keerthi [11].Publication Second hankel determinant for a general subclass of bi-univalent functions(Inst Applied Mathematics, 2016-01-01) Altınkaya, Şahsene; Yalçın, Sibel; ALTINKAYA, ŞAHSENE; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-7950-8450; 0000-0002-0243-8263; ABC-6175-2020; AAE-9745-2020; AAA-8330-2021Making use of the Hankel determinant, in this work, we consider a general subclass of bi-univalent functions. Moreover, we investigate the bounds of initial coefficients of this class.Publication Third hankel determinant and zalcman functional for a class of starlike functions with respect to symmetric points related with sine function(Int Scientific Research Publications, 2022-01-01) Khan, Muhammad Ghaffar; Ahmad, Bakhtiar; Murugusundaramoorthy, Gangadharan; Mashwani, Wali Khan; Yalçın, Sibel; Shaba, Timilehin Gideon; Salleh, Zabidin; YALÇIN TOKGÖZ, SİBEL; Fen Edebiyat Fakültesi; Matematik Bölümü; 0000-0002-0243-8263; AAE-9745-2020In this article we define a class of starlike functions with respect to symmetric points in the domain of sine function. Also, we investigate coefficients bounds and upper bounds for the third order Hankel determinant for this defined class. We also evaluate the Zalcman functiona vertical bar a2/3 - a(5)vertical bar. Specializing the parameters, we improve Zalcman functional for the class of starlike functions.