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In the present paper, taking into account recent conractive technique, which is called F-contraction, we provide some new fixed point results for multivalued mapping on some kind of complete quasi metric spaces.
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 heavily advanced statistical analysis. The use of data mining techniques is fairly new. This paper compares three feature selection algorithms on medical data sets and comments on...
Power system simulations, most of the time, require solution of a large sparse linear system. Traditional methods, such as LU decomposition based direct methods, are not suitable for parallelization in general. Thus, Krylov subspace based iterative methods (i.e. Conjugate Gradient, Generalized Minimal Residuals (GMRES)) can be used as very good alternatives compared to direct methods. On the other...
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 contingency analyses comprise of the outages of the branches, transformers and other power system components. This paper solves branch outage problem using a bounded approach. Harmony...
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 requiring reasonable accuracies. On the other hand, accuracy of the results and the speed of calculation depend on branch outage modeling as well as solution algorithm used. This paper...
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 outages are within the acceptable limits, the system is called secure. In this paper we solve the contingency problem using a recently developed local constrained optimization based...
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 for rational Krylov methods. These methods require huge memory and computational power especially in large scale simulations. Therefore, these methods are fairly suitable for parallel...
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 of physics. The difficulty in capturing students' attention in class for a long time also plays a role in less effective teaching during learning activities. Research shows that...
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 costs of hardware and advanced package programs and techniques encourage researchers to apply parallel programming to the problems that are either too much time consuming or impossible...
Contingency studies such as branch outage and generator outage are among important studies of energy management centers operations. Branch outage modeling, on the other hand, is one of the basic steps of post-outage state estimation of an electrical power system. Real time implementation of the problem brings the necessity of using high speed methods while providing a reasonable accuracy. This paper...
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, we use a minimization method that minimizes the errors resulting from the linear system model implementation. We solve the optimization problem, using particle swarm optimization...
A new solution methodology for the constant matrix, decoupled power flow problem is presented in this paper. The proposed method uses the conjugate gradient method instead of the traditional direct solution of Ax = b for updating the power flow variables. The conjugate gradient method is accelerated with an approximate inverse matrix preconditioner obtained from a linear combination of matrix-valued...
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