Onur Tolga Sehitoglu

@metu.edu.tr

Computer Engineering Department
Middle East Technical University

Onur Tolga Sehitoglu

RESEARCH INTERESTS

evolutionary computation, systems security, programming languages
7

Scopus Publications

188

Scholar Citations

7

Scholar h-index

6

Scholar i10-index

Scopus Publications

  • Programming with Python for Engineers
    Sinan Kalkan, Onur T. Şehitoğlu, Göktürk Üçoluk
    Programming with Python for Engineers, 2024
  • Short-term trend prediction in financial time series data
    Mustafa Onur Özorhan, İsmail Hakkı Toroslu, Onur Tolga Şehitoğlu
    Knowledge and Information Systems, 2019
    This paper presents a method to predict short-term trends in financial time series data found in the foreign exchange market. Trends in the Forex market appear with similar chart patterns. We approach the chart patterns in the financial markets from a discovery of motifs in a time series perspective. Our method uses a modified Zigzag technical indicator to segment the data and discover motifs, expectation maximization to cluster the motifs and support vector machines to classify the motifs and predict accurate trading parameters for the identified motifs. The available input data are adapted to each trading time frame with a sliding window. The accuracy of the prediction models is tested across several different currency pairs, spanning 5 years of historical data from 2010 to 2015. The experimental results suggest that using the Zigzag technical indicator to discover motifs that identify short-term trends in financial data results in a high prediction accuracy and trade profits.
  • A strength-biased prediction model for forecasting exchange rates using support vector machines and genetic algorithms
    Mustafa Onur Özorhan, İsmail Hakkı Toroslu, Onur Tolga Şehitoğlu
    Soft Computing, 2017
    This paper addresses problem of predicting direction and magnitude of movement of currency pairs in the foreign exchange market. The study uses Support Vector Machine with a novel approach for input data and trading strategy. The input data contain technical indicators generated from currency price data (i.e., open, high, low and close prices) and representation of these technical indicators as trend deterministic signals. The input data are also dynamically adapted to each trading day with genetic algorithm. The study incorporates a currency strength-biased trading strategy which selects the best pair to trade from the available set of currencies and is an improvement over the previous work. The accuracy of the prediction models are tested across several different sets of technical indicators and currency pair sets, spanning 5 years of historical data from 2010 to 2015. The experimental results suggest that using trend deterministic technical indicator signals mixed with raw data improves overall performance and dynamically adapting the input data to each trading period results in increased profits. Results also show that using a strength-biased trading strategy among a set of currency pair increases the overall prediction accuracy and profits of the models.
  • Three-dimensional structural topology optimization of aerial vehicles under aerodynamic loads
    Erdal Oktay, Hasan U. Akay, Onur T. Sehitoglu
    Computers and Fluids, 2014
    A previously developed density distribution-based structural topology optimization algorithm coupled with a Computational Fluid Dynamics (CFD) solver for aerodynamic force predictions is extended to solve large-scale problems to reveal inner structural details of a wing wholly rather than some specific regions. Resorting to an iterative conjugate gradient algorithm for the solution of the structural equilibrium equations needed at each step of the topology optimizations allowed the solution of larger size problems, which could not be handled previously with a direct equation solver. Both the topology optimization and CFD codes are parallelized to obtain faster solutions. Because of the complexity of the computed aerodynamic loads, a case study involving optimization of the inner structure of the wing of an unmanned aerial vehicle (UAV) led to topologies, which could not be obtained by intuition alone. Post-processing features specifically tailored for visualizing computed topologies proved to be good design tools in the hands of designers for identifying complex structural components.
  • SEMbySEM in action: Domain name registry service through a semantic middleware
    Echallenges E 2010 Conference, 2010
  • A pattern classification approach for boosting with genetic algorithms
    Ismet Yalabik, Fatos T. Yarman-Vural, Gokturk Ucoluk, Onur Tolga Sehitoglu
    22nd International Symposium on Computer and Information Sciences Iscis 2007 Proceedings, 2007
    Ensemble learning is a multiple-classifier machine learning approach which produces collections and ensembles statistical classifiers to build up more accurate classifier than the individual classifiers. Bagging, boosting and voting methods are the basic examples of ensemble learning. In this study, a novel boosting technique targeting to solve partial problems of AdaBoost, a well-known boosting algorithm, is proposed. The proposed system finds an elegant way of boosting a bunch of classifiers successively to form a "better classifier" than each ensembled classifiers. AdaBoost algorithm employs a greedy search over hypothesis space to find a ";good"; suboptimal solution. On the hand, the system proposed employs an evolutionary search with genetic algorithms instead of greedy search. Empirical results show that classification with boosted evolutionary computing outperforms the classical AdaBoost in equivalent experimental environments.
  • Gene level concurrency in genetic algorithms
    Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics, 2003

RECENT SCHOLAR PUBLICATIONS

  • Representation of Data
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 35-53 , 2024
    2024
  • File Handling
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 173-195 , 2024
    2024
  • Programming and Programming Languages
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 19-33 , 2024
    2024
  • An Application: Solving a Simple Regression Problem
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 263-275 , 2024
    2024
  • Scientific and Engineering Libraries
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 221-248 , 2024
    2024
  • A Gentle Introduction to Object-Oriented Programming
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 147-171 , 2024
    2024
  • Dive into Python
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 55-94 , 2024
    2024
  • Computing and Computers
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 1-18 , 2024
    2024
  • Error Handling and Debugging
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 197-219 , 2024
    2024
  • An Application: Approximation and Optimization
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 249-262 , 2024
    2024
  • Conditional and Repetitive Execution
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 95-118 , 2024
    2024
  • Programming with Python for Engineers
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Springer , 2024
    2024
    Citations: 1
  • Onur Tolga Şehitoğlu
    OT Şehitoğlu
    2020
  • Short-term trend prediction in financial time series data
    MO Özorhan, İH Toroslu, OT Şehitoğlu
    Knowledge and Information Systems 61 (1), 397-429 , 2019
    2019
    Citations: 32
  • A parallel aerostructural shape optimization platform for airplane wings
    E Oktay, A Arpacı, O Sehitoglu, HU Akay
    null , 2019
    2019
    Citations: 1
  • A strength-biased prediction model for forecasting exchange rates using support vector machines and genetic algorithms
    MO Özorhan, İH Toroslu, OT Şehitoğlu
    Soft Computing 21 (22), 6653-6671 , 2017
    2017
    Citations: 43
  • Three-dimensional structural topology optimization of aerial vehicles under aerodynamic loads
    E Oktay, HU Akay, OT Sehitoglu
    Computers & Fluids 92, 225-232 , 2014
    2014
    Citations: 39
  • CEng 536 ADVANCED UNIX Fall 2011 Syllabus
    OT Sehitoglu
    2011
  • SEMbySEM in action: Domain name registry service through a semantic middleware
    AA Sınacı, OT Şehitoğlu, MT Yondem, G Fidan, I Tatli
    2010
  • Programming Language Concepts
    OT Şehitoğlu
    2010

MOST CITED SCHOLAR PUBLICATIONS

  • A strength-biased prediction model for forecasting exchange rates using support vector machines and genetic algorithms
    MO Özorhan, İH Toroslu, OT Şehitoğlu
    Soft Computing 21 (22), 6653-6671 , 2017
    2017
    Citations: 43
  • Three-dimensional structural topology optimization of aerial vehicles under aerodynamic loads
    E Oktay, HU Akay, OT Sehitoglu
    Computers & Fluids 92, 225-232 , 2014
    2014
    Citations: 39
  • Short-term trend prediction in financial time series data
    MO Özorhan, İH Toroslu, OT Şehitoğlu
    Knowledge and Information Systems 61 (1), 397-429 , 2019
    2019
    Citations: 32
  • A building block favoring reordering method for gene positions in genetic algorithms
    OT Sehitoglu, G Ucoluk
    Proceedings of the Genetic and Evolutionary Computation Conference, 571-575 , 2001
    2001
    Citations: 19
  • An outline of Turkish syntax
    E Göçmen, OT Sehitoglu, C Bozsahin
    Ms. Department of Computer Engineering, 1-36 , 1995
    1995
    Citations: 15
  • A pattern classification approach for boosting with genetic algorithms
    I Yalabik, FT Yarman-Vural, G Ucoluk, OT Sehitoglu
    2007 22nd international symposium on computer and information sciences, 1-6 , 2007
    2007
    Citations: 12
  • Lexical rules and lexical organization: Productivity in the lexicon
    OT Sehitoglu, C Bozsahin
    Breadth and Depth of Semantic Lexicons, 39-57 , 1999
    1999
    Citations: 8
  • A sign-based phrase structure grammar for Turkish
    OT Sehitoglu
    arXiv preprint cmp-lg/9608016 , 1996
    1996
    Citations: 6
  • A sign-based phrase structure grammer for Turkish.
    OT Şehitoğlu
    Middle East Technical University , 1996
    1996
    Citations: 6
  • Gene level concurrency in genetic algorithms
    OT Şehitoğlu, G Üçoluk
    International Symposium on Computer and Information Sciences, 976-983 , 2003
    2003
    Citations: 3
  • Gene Reordering and Concurrency in Genetic Algorithms
    OT Sehitoglu
    PhD thesis, Computer Engineering Dept, METU, Ankara , 2002
    2002
    Citations: 2
  • Programming with Python for Engineers
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Springer , 2024
    2024
    Citations: 1
  • A parallel aerostructural shape optimization platform for airplane wings
    E Oktay, A Arpacı, O Sehitoglu, HU Akay
    null , 2019
    2019
    Citations: 1
  • Morphological productivity in the lexicon
    OT Sehitoglu, C Bozsahin
    Breadth and Depth of Semantic Lexicons , 1996
    1996
    Citations: 1
  • Representation of Data
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 35-53 , 2024
    2024
  • File Handling
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 173-195 , 2024
    2024
  • Programming and Programming Languages
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 19-33 , 2024
    2024
  • An Application: Solving a Simple Regression Problem
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 263-275 , 2024
    2024
  • Scientific and Engineering Libraries
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 221-248 , 2024
    2024
  • A Gentle Introduction to Object-Oriented Programming
    S Kalkan, OT Şehitoğlu, G Üçoluk
    Programming with Python for Engineers, 147-171 , 2024
    2024