Aksoy, Ümit
Loading...
Name Variants
U., Aksoy
A., Umit
Ü., Aksoy
Aksoy,U.
Aksoy,Umit
Aksoy, Umit
Umit, Aksoy
U.,Aksoy
Ü.,Aksoy
Ümit Aksoy
A.,Umit
Aksoy U.
Aksoy, Ümit
Aksoy,Ü.
Ümit, Aksoy
A., Ümit
A.,Ümit
Aksoy, U.
Aksoy, Ue.
Aksoy, Ue
A., Umit
Ü., Aksoy
Aksoy,U.
Aksoy,Umit
Aksoy, Umit
Umit, Aksoy
U.,Aksoy
Ü.,Aksoy
Ümit Aksoy
A.,Umit
Aksoy U.
Aksoy, Ümit
Aksoy,Ü.
Ümit, Aksoy
A., Ümit
A.,Ümit
Aksoy, U.
Aksoy, Ue.
Aksoy, Ue
Job Title
Profesör Doktor
Email Address
umit.aksoy@atilim.edu.tr
Main Affiliation
Mathematics
Status
Website
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Scholarly Output
40
Articles
31
Citation Count
445
Supervised Theses
2
40 results
Scholarly Output Search Results
Now showing 1 - 10 of 40
Article Citation - WoS: 0Citation - Scopus: 0Dirichlet-Type Problems for n-poisson Equation in Clifford Analysis(Taylor & Francis Ltd, 2022) Aksoy, Umit; Celebi, A. Okay; MathematicsIterated Dirichlet problem, also called as Riquier or Navier problem, and polyharmonic Dirichlet problem are studied for n-Poisson equation in Clifford analysis using iterated polyharmonic Green function and polyharmonic Green-Almansi type function appropriate for the boundary conditions of the problems.Article Citation - WoS: 23Citation - Scopus: 30Fixed Point Theorems in Complete Modular Metric Spaces and an Application To Anti-Periodic Boundary Value Problems(Univ Nis, Fac Sci Math, 2017) Aksoy, Umit; Karapinar, Erdal; Erhan, Inci M.; MathematicsIn this paper existence and uniqueness of fixed points for a general class of contractive and nonexpansive mappings on modular metric spaces is discussed. As an application of the theoretical results, the existence of a solution of anti-periodic boundary value problems for nonlinear first order differential equations of Caratheodory's type is considered in the framework of modular metric spaces.Article Neumann problem for generalized n-Poisson equation(Journal of Mathematical Analysis and Applications, 2009) Aksoy, Ümit; Çelebi, Okay; MathematicsUsing a hierarchy of integral operators having higher-order Neumann functions and their derivatives as kernels, the Neumann problem for a 2nth order linear partial complex differential equation is discussed. The solvability of the problem is obtained.Article A Hierarchy of Singular Integral Operators for Mixed Boundary Value Problems(2011) Aksoy, Ümit; Çelebi, Okay; MathematicsA class of integral operators having a hierarchy of polyharmonic kernels is introduced and some properties are derived. Iterated mixed boundary value problems for complex model equations and linear elliptic complex partial differential equations are discussed in the unit disc of the complex plane.Article Weak Ψ -Contractions on Partially Ordered Metric Spaces and Applications To Boundary Value Problems(2015) Aksoy, Ümit; MathematicsRecent developments in fixed point theory have been encouraged by the applicability of the results in the area of boundary value problems for differential and integral equations. Especially in the last few years, a lot of publications in fixed point theory have presented results directly related to specific initial or boundary value problems. These problems include not only ordinary and partial differential equations, but also fractional differential equations.Article Norm Estimates of a Class of Calderon–zygmund Type Strongly Singular Integral Operators(Integral Transforms and Special Functions, 2007) Aksoy, Ümit; Çelebi, Okay; MathematicsIn this article, we prove the Lp boundedness of a class of Calderon–Zygmund type strongly singular operators. In particular, we give an estimate for the L2 norm of these operators in the unit disc of the complex plane.Article Citation - WoS: 1Citation - Scopus: 2Optimal Limit Order Book Trading Strategies With Stochastic Volatility in the Underlying Asset(Springer, 2023) Aydogan, Burcu; Ugur, Omur; Aksoy, Umit; MathematicsIn quantitative finance, there have been numerous new aspects and developments related with the stochastic control and optimization problems which handle the controlled variables of performing the behavior of a dynamical system to achieve certain objectives. In this paper, we address the optimal trading strategies via price impact models using Heston stochastic volatility framework including jump processes either in price or in volatility of the price dynamics with the aim of maximizing expected return of the trader by controlling the inventories. Two types of utility functions are considered: quadratic and exponential. In both cases, the remaining inventories of the market maker are charged with a liquidation cost. In order to achieve the optimal quotes, we control the inventory risk and follow the influence of each parameter in the model to the best bid and ask prices. We show that the risk metrics including profit and loss distribution (PnL), standard deviation and Sharpe ratio play important roles for the trader to make decisions on the strategies. We apply finite differences and linear interpolation as well as extrapolation techniques to obtain a solution of the nonlinear Hamilton-Jacobi-Bellman (HJB) equation. Moreover, we consider different cases on the modeling to carry out the numerical simulations.Article Citation - WoS: 45Citation - Scopus: 47F-Contraction Mappings on Metric-Like Spaces in Connection With Integral Equations on Time Scales(Springer-verlag Italia Srl, 2020) Agarwal, Ravi P.; Aksoy, Umit; Karapinar, Erdal; Erhan, Inci M.; MathematicsIn this paper we investigate the existence and uniqueness of fixed points of certain (phi,F)-type contractions in the frame of metric-like spaces. As an application of the theorem we consider the existence and uniqueness of solutions of nonlinear Fredholm integral equations of the second kind on time scales. We also present a particular example which demonstrates our theoretical results.Article Citation - WoS: 1Citation - Scopus: 2Fixed Point Theorems for Mappings With a Contractive Iterate at a Point in Modular Metric Spaces(House Book Science-casa Cartii Stiinta, 2022) Karapinar, Erdal; Aksoy, Umit; Fulga, Andreea; Erhan, Inci M.; MathematicsIn this manuscript, we introduce two new types of contraction, namely, w-contraction and strong Sehgal w-contraction, in the framework of modular metric spaces. We indicate that under certain assumptions, such mappings possess a unique fixed point. For the sake of completeness, we consider examples and an application to matrix equations.Article Citation - WoS: 118Citation - Scopus: 126Uniqueness of Solution for Higher-Order Nonlinear Fractional Differential Equations With Multi-Point and Integral Boundary Conditions(Springer-verlag Italia Srl, 2021) Sevinik-Adiguzel, Rezan; Aksoy, Umit; Karapinar, Erdal; Erhan, Inci M.; MathematicsThis study is devoted to the development of alternative conditions for existence and uniqueness of nonlinear fractional differential equations of higher-order with integral and multi-point boundary conditions. It uses a novel approach of employing a fixed point theorem based on contractive iterates of the integral operator for the corresponding fixed point problem. We start with developing an existence-uniqueness theorem for self-mappings with contractive iterate in a b-metric-like space. Then, we obtain the unique solvability of the problem under suitable conditions by utilizing an appropriate b-metric-like space.
