Fakülteler by Institution Author "Dağ, Hasan"
Now showing items 1-20 of 29
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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 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 ... -
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 its solution using differential evolution method
Ceylan, Oğuzhan; Ozdemir, Aydogan; Dağ, Hasan (2011)Power system operators need to check the system security by contingency analysis which requires power flow solutions repeatedly. AC power flow is computationally slow even for a moderately sized system. Thus fast and ... -
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 ... -
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 ... -
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 ... -
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. ... -
On the selection of ınterpolation points for rational Krylov Methods
Yetkin, E. Fatih; Dağ, Hasan (Springer-Verlag Berlin, 2012)We suggest a simple and an efficient way of selecting a suitable set of interpolation points for the well-known rational Krylov based model order reduction techniques. To do this some sampling points from the frequency ... -
On-Line Transient Stability Assessment Using Matlab Parallel Programming Environment
Soykan, Gürkan; Dağ, Hasan (IEEE, 2010)Transient Stability Assessment (TSA) is the major part of Dynamic Security Assessment (DSA) in an electric power system. On-line TSA has gained more importance for power system security in last two decades. The decreasing ... -
Parallel Contingency Analysis Using Differential Evolution Based Solution For Branch Outage Problem
Ceylan, Oğuzhan; Dağ, Hasan; Özdemir, Aydoğan (IEEE, 2010)Contingency analysis is one of the most fundamental work an electricity management center operator has to perform regularly. If both bus voltage magnitudes and reactive power flowing on the branches during any type of ... -
Parallel Implementation Of Iterative Rational Krylov Methods For Model Order Reduction
Yetkin, E. Fatih; Dağ, Hasan (IEEE, 2010)Model order reduction (MOR) techniques are getting more important in large scale computational tasks like large scale electronic circuit simulations. In this paper we present some experimental work on multiprocessor systems ... -
Parallel implementation of iterative rational Krylov methods for model order reduction
Yetkin, Emrullah Fatih; Dağ, Hasan (IEEE, 2009)Model order reduction (MOR) techniques are getting more important in large scale computational tasks like large scale electronic circuit simulations. In this paper we present some experimental work on multiprocessor systems ... -
Parallel-in-space implementation of transient stability analysis on a Linux cluster with infiniband
Soykan, Gürkan; Flueck, Alexander J.; Dağ, Hasan (IEEE, 2012)On-line transient stability analysis is an inevitable way to provide real time power system security and control. Parallel computing is one of the most viable ways to perform on-line transient stability analysis. This paper ...