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Dr. Gizem Seyhan Öztepe
Department of Mathematics, Ankara University, Ankara, Turkey (Türkiye)
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Academic Career Length
18Years (2009-Present)
(Calculated once Scilit publication data is synced: current year − year of first publication + 1)
Representative Publications
View All Publications20 April 2010 in Mathematical Modelling and Analysis
Journal Article
HBHüseyin Bereketoglu
Hüseyin BereketogluGÖGizem Seyhan Öztepe
Gizem Seyhan ÖztepeAOAşar Ogun
Aşar Ogun
We prove the existence and uniqueness of the solutions of a class of first order nonhomogeneous advanced impulsive differential equations with piecewise constant arguments. We also study the conditions of periodicity, oscillation, nonoscillation and global asymptotic stability for some special cases.
6 February 2009 in Acta Applicandae Mathematicae
Journal Article
FKFatma Karakoc
Fatma KarakocHBHuseyin Bereketoglu
Huseyin BereketogluGÖGizem Seyhan Öztepe
Gizem Seyhan Öztepe11 March 2018 in Georgian Mathematical Journal
Journal Article
HBHuseyin Bereketoglu
Huseyin BereketogluFKFATMA KARAKOÇ
FATMA KARAKOÇGÖGizem Seyhan Öztepe
Gizem Seyhan Öztepe
Ioannis StavroulakisConsider the first-order linear differential equation with several non-monotone retarded arguments x ′ ( t ) + ∑ i = 1 m p i ( t ) x ( τ i ( t ) ) = 0 {x^{\prime}(t)+\sum_{i=1}^{m}p_{i}(t)x(\tau_{i}(t))=0} , t ≥ t 0 {t\geq t_{0}} , where the functions p i , τ i ∈ C ( [ t 0 , ∞ ) , ℝ + ) {p_{i},\tau_{i}\in C([t_{0},\infty),\mathbb{R}^{+})} , for every i = 1 , 2 , … , m {i=1,2,\ldots,m} , τ i ( t ) ≤ t {\tau_{i}(t)\leq t} for t ≥ t 0 {t\geq t_{0}} and lim t → ∞ τ i ( t ) = ∞ {\lim_{t\to\infty}\tau_{i}(t)=\infty} . New oscillation criteria which essentially improve the known results in the literature are established. An example illustrating the results is given.
1 January 2013 in Miskolc Mathematical Notes
Journal Article
HBHuseyin Bereketoglu
Huseyin BereketogluGÖGizem Seyhan Öztepe
Gizem Seyhan Öztepe20 December 2017 in Communications in Mathematics
Journal Article
GÖGizem Seyhan Öztepe
Gizem Seyhan ÖztepeFKFATMA KARAKOÇ
FATMA KARAKOÇHBHuseyin Bereketoglu
Huseyin BereketogluThis paper concerns with the existence of the solutions of a second order impulsive delay differential equation with a piecewise constant argument. Moreover, oscillation, nonoscillation and periodicity of the solutions are investigated.
1 January 2017 in Hacettepe Journal of Mathematics and Statistics
Journal Article
GÖGizem Seyhan Öztepe
Gizem Seyhan ÖztepeAbout Me
Gizem S.Oztepe received her B.S., M.S., and Ph.D. degrees in mathematics from Ankara University, Turkey, in 2005, 2009, and 2013, respectively. Between 2014 and 2015, she was a postdoctoral researcher in the Department of Mathematics at the University of Central Florida (UCF), Orlando, USA. She is currently an Associate Professor in the Department of Mathematics at Ankara University. Dr. Oztepe also serves as an Area Editor for the journal "Communications Faculty of Sciences University of Ankara Series A1 Mathematics and Statistics". She has been a member of the American Mathematical Society (AMS) since 2016 and the International Society of Difference Equations (ISDE) since 2023. Her research interests encompass differential equations with piecewise constant arguments, impulsive differential equations, difference equations, fractional differential equations, bifurcation theory, the qualitative behavior of dynamical systems.