Browsing Yönetim Bilişim Sistemleri Bölümü Koleksiyonu by Author "Dağ, Hasan"
Now showing items 1-20 of 38
-
Applications of Eigenvalue Counting and Inclusion Theorems in Model Order Reduction
Yetkin, E. Fatih; Dağ, Hasan (Springer-Verlag Berlin, 2010)We suggest a simple and an efficient iterative method based on both the Gerschgorin eigenvalue inclusion theorem and the deflation methods to compute a Reduced Order Model (ROM) to lower greatly the order of a given state ... -
Branch outage simulation based contingency screening by gravitational search algorithm
Ceylan, Oğuzhan; Özdemir, Aydoğan; Dağ, Hasan (Praise Worthy Prize Srl, 2012)Power systems contingency analysis is an important issue for electric power system operators. This paper performs branch outage simulation based contingency screening using a bounded network approach. Local constrained ... -
Branch outage solution using particle swarm optimization
Ceylan, Oğuzhan; Ozdemir, Aydogan; Dağ, Hasan (2008)For post outage MW line flows and voltage magnitude calculations most of the methods use linear methods because of their simplicity. Especially for reactive power flow calculations one can face high errors. In this paper ... -
Comparison of Cost-Free Computational Tools for Teaching Physics
Er, Neslihan Fatma; Dağ, Hasan (IEEE, 2010)It is widely accepted that it is quite difficult to engage today's students, from high schools to university, both in educational activities in class and "teaching" them physics due to their prejudices about the complexity ... -
Comparison of feature selection algorithms for medical data
Dağ, Hasan; Sayın, Kamran Emre; Yenidoğan, Işıl; Albayrak, Songül Varli; Acar, Can (IEEE, 2012)Data mining application areas widen day by day. Among those areas medical area has been receiving quite a big attention. However working with very large data sets with many attributes is hard. Experts in this field use ... -
Comparison of post outage bus voltage magnitudes estimated by harmony search and differential evolution methods
Ceylan, Oğuzhan; Özdemir, Aydoğan; Dağ, Hasan (2009)Contingency studies are indispensable tools of both the power system planning and operational studies. Real time implementation of operational problems makes necessary the use of high speed computational methods while ... -
Distributed Memory Parallel Transient Stability Analysis on a PC Cluster with Ethernet
Soykan, Gürkan; Flueck, Alexander J.; Dağ, Hasan (Praise Worthy Prize Srl, 2010)On-line transient stability analysis is a necessity for real-time power system control and security. Parallel processing is a natural technology for achieving real-time solution performance. This paper presents a ... -
Double branch outage modeling and simulation: Bounded network approach
Ceylan, Oğuzhan; Özdemir, Aydoğan; Dağ, Hasan (Elsevier Science, 2015)Energy management system operators perform regular outage simulations in order to ensure secure operation of power systems. AC power flow based outage simulations are not preferred because of insufficient computational ... -
AN EFFECTIVE ROCOMMENDER MODEL FOR E-COMMERCE PLATFORMS
Işık, Muhittin; Dağ, Hasan (2017)Sahte kullanıcı hesapları, veri tabalarındaki seyreklik problemlerinden dolayı özellikle yeteri kadar kullanıcı tarafından puanlanmamış ürünlerde tavsiye algoritmalarını kolaylıkla etkileyebilmektedirler. Genellikle bu ... -
Feature Extraction Based on Deep Learning for Some Traditional Machine Learning Methods
Çayır, Aykut; Yenidoğan, Işıl; Dağ, Hasan (Institute of Electrical and Electronics Engineers Inc., 2018)Deep learning is a subfield of machine learning and deep neural architectures can extract high level features automatically without handcraft feature engineering unlike traditional machine learning algorithms. In this ... -
A Generic Framework for Building Heterogeneous Simulations of Parallel and Distributed Computing Systems
Dursun, Taner; Dağ, Hasan (Springer Heidelberg, 2017)There have been many systems available for parallel and distributed computing (PDC) applications such as grids clusters super-computers clouds peer-to-peer and volunteer computing systems. High-performance computing (HPC) ... -
Gravitational search algorithm for post-outage bus voltage magnitude calculations
Ceylan, Oğuzhan; Ozdemir, Aydogan; Dağ, Hasan (2010)Branch outage problem is one of the key problems in power system security analysis. This paper solves branch outage problem using a bounded approach. Local constrained optimization problem in the bounded approach is solved ... -
Harmony search method based parallel contingency analysis
Ceylan, Oğuzhan; Dağ, Hasan; Ozdemir, Aydogan (2010)Power system security management is one of the key problems in power system analysis. Power system management center operators need to simulate contingencies as fast as possible and take the remedial actions in time. These ... -
HeteroSim: Heterogeneous simulation framework
Dursun, Taner; Dağ, Hasan (Association for Computing Machinery, 2009)In order to arrange heterogeneous simulation executions it would be useful to have simulation tools that enable easy and fast creation of simulation sessions employing real-time software components beside simulation codes. ... -
Heuristic Methods for Postoutage Voltage Magnitude Calculations
Ceylan, Oğuzhan; Özdemir, Aydogan; Dağ, Hasan (TUBITAK Scientific & Technical Research Council Turkey, 2016)Power systems play a significant role in every aspect of our daily lives. Hence their continuation without any interruption (or with the least duration of interruption due to faults or scheduled maintenances) is one of the ... -
The impact of text preprocessing on the prediction of review ratings
Işık, Muhittin; Dağ, Hasan (Tubitak, 2020)With the increase of e-commerce platforms and online applications, businessmen are looking to have a rating and review system through which they can easily reveal the feelings of customers related to their products and ... -
Implementation of a SDN (Software defined network)
Ergen, Mithat Sinan; Kutlan, Sarp; Dağ, Tamer; Dağ, Hasan (International Institute of Informatics and Systemics IIIS, 2014)Improving resource efficiency enhancing network security and achieving simpler network management have become the main goals for networking in the previous years. To accomplish these ideas an efficient routing traffic ... -
Konutların Günlük Elektrik Güç Tüketimi Tahmini İçin Uygun Model Seçimi
Çayır, Aykut; Dağ, Hasan (Fırat Üniv. Fen Bilimleri Enst., 2018)Zamana bağlı değişim gösteren olayların modellenmesi zorlu bir veri analizi problemidir. Bu olaylardan biri olan elektrik güç tüketiminde ise veriden mevsimsel etki ve tatil günleri gibi örüntülerin öğrenilerek bir ... -
Machine learning model to predict an adult learner's decision to continue ESOL course
Dahman, Mohammed R.; Dağ, Hasan (Springer, 2019)This study investigated the ability of the demographic and the affective variables to predict the adult learners' decision to continue ESOL courser. 278 adult learners, enrolled on ESOL course at FLS institution in Istanbul, ... -
A New Preconditioner Design Based on Spectral Division for Power Flow Analysis
Dağ, Hasan; Yetkin, E. Fatih; Manguoglu, Murat (Praise Worthy Prize Srl, 2011)Solution of large sparse linear systems is the most lime consuming part in many power system simulations. Direct solvers based on LU factorization although robust are known to have limited satiability on parallel platforms. ...