WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653
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Article Citation - WoS: 2Citation - Scopus: 9Predicting Financial Failure of the Turkish Banks(World Scientific Publ Co Pte Ltd, 2006) Doganay, M. Mete; Ceylan, Nildag Basak; Aktas, Ramazan; Akta, RamazanBanks are the most important financial institutions in Turkey because other financial institutions are not developed efficiently yet. Turkish banks experienced financial difficulties and a substantial amount of banks failed in the past. This event urged the government to initiate measures to prevent banks from getting into financial difficulties. As a result of these measures, Turkish banking system currently seems to be very attractive for the foreign investors willing to invest in this sector. One of the main concerns of the foreign investors is a possibility of a new banking crisis although it is very remote at this time. The purpose of this study is to develop early warning systems predicting the financial failure at least three years ahead of financial date. A number of multivariate statistical models such as multiple regression, discriminant analysis, logit, probit are used. We found that the most appropriate model is logit. The significant variables obtained from the models explain very well the causes of the bank failures. Our models can be used to assist interested parties to predict the probability of financial failure of Turkish banks.Article Citation - WoS: 2Citation - Scopus: 2The Hamilton-Jacobi Treatment of Front-Form Schwinger Model(World Scientific Publ Co Pte Ltd, 2002) Gulerz, Yurdahan; Baleanu, Dumitru; Güler, YurdahanThe Hamilton-Jacobi formalism was applied to quantize the front-form Schwinger model. The importance of the surface term is discussed in detail. The BRST-anti-BRST symmetry was analyzed within Hamilton-Jacobi formalism.Article Citation - WoS: 4Citation - Scopus: 4Phase Changes in Icosahedral 54-, 55-, 56-Atom Platinum Clusters(World Scientific Publ Co Pte Ltd, 2004) Güvenç, ZB; Kökten, H; Sebetci, AUsing the Voter and Chen version of an embedded-atom model, derived by fitting simultaneously to experimental data both the diatomic molecule and bulk platinum, we have studied the melting behavior of free, icosahedral, 54-, 55- and 56-atom platinum clusters in the molecular dynamics simulation technique. We present an atom-resolved analysis method that includes physical quantities such as the root-mean-square bond-length fluctuation and coordination number for individual atoms as functions of temperature. The effect of a central atom in the icosahedral structure to the melting process is discussed. The results show that the global minimum structures of the 54-, 55- and 56-atom Pt clusters do not melt at a specific temperature, rather, melting processes take place over a finite temperature range. The heat capacity peaks are not delta-functions, but instead remain finite. An ensemble of clusters in the melting region is a mixture of solid-like and liquid-like clusters.Article Citation - WoS: 3Citation - Scopus: 3Finite Size Scaling by Using Scaling Functions in Two-Dimensional Q=2 and 7 State Potts Models(World Scientific Publ Co Pte Ltd, 2001) Seferoglu, N; Aydin, M; Gündüç, Y; Demirtürk, SThe scaling behaviors of the percolation cumulant and the surface renormalization are studied on q = 2 and 7 state Potts models. The results show that the scaling functions can be safely used to determine infinite lattice transition points and the thermal and magnetic exponents indicating that these functions have very small correction to scaling contributions.Article Citation - WoS: 1Citation - Scopus: 1A New Approach To Dynamic Finite-Size Scaling(World Scientific Publ Co Pte Ltd, 2003) Gündüç, S; Aydin, M; Gündüç, Y; Dilaver, MIn this work we have considered the Taylor series expansion of the dynamic scaling relation of the magnetization with respect to small initial magnetization values in order to study the dynamic scaling behavior of two- and three-dimensional Ising models. We have used the literature values of the critical exponents and of the new dynamic exponent x(0) to observe the dynamic finite-size scaling behavior of the time evolution of the magnetization during early stages of the Monte Carlo simulation. For the three-dimensional Ising model we have also presented that this method opens the possibility of calculating z and x(0) separately. Our results show good agreement with the literature values. Measurements done on lattices with different sizes seem to give very good scaling.Article Citation - WoS: 7Citation - Scopus: 7Structure and Dynamical Properties of Aun, N=12-14 Clusters: Molecular Dynamics Simulation(World Scientific Publ Co Pte Ltd, 2005) Yildirim, EK; Atis, M; Güvenç, ZBUsing molecular dynamics and thermal quenching methods on the basis of Voter-Chen version of the embedded-atom method, we have studied the melting behavior of Au-N (N = 12, 13, 14) clusters. This behavior is described in terms of overall and atom resolved root-mean-square bond-length fluctuations, specific-heat, short- and long-time average coordination numbers of each atom and short-time average temperatures of the clusters. The isomer sampling probabilities are obtained from the thermal quenching of the molten clusters, and their energy-spectrum widths are investigated. Phase change of a cluster takes place with the collective and simultaneous motion of all the atoms.Article Citation - WoS: 18Citation - Scopus: 19Reaction Dynamics of Nin (N=19 and 20) With D2: Dependence on Cluster Size, Temperature and Initial Rovibrational States of the Molecule(World Scientific Publ Co Pte Ltd, 2005) Böyükata, M; Güvenç, ZB; Özçelik, S; Durmus, P; Jellinek, JThe Ni(n)(n = 19, 20) + D2(v, j) collision systems have been studied to investigate the dependence of cluster reactivity on the cluster temperature and the initial rovibrational states of the molecule using quasiclassical molecular dynamics simulations. The clusters are described by an embedded atom potential, whereas the interaction between the molecule and the cluster is modeled by a LEPS (London-Eyring-Polani-Sato) potential energy function. Reaction (dissociative adsorption) cross-sections are computed as functions of the collision energy for different initial rovibrational states of the molecule and for different temperatures of the clusters. Rovibrational, temperature and size-dependent rate constants are also presented, and the results are compared with earlier studies. Initial vibrational excitation of the molecule increases the reaction cross-section more efficiently than the initial rotational excitation. The reaction cross-sections strongly depend on the collision energies below 0.1 eV.Article Citation - WoS: 18Citation - Scopus: 21Multi-Hamilton Quantization of O(3) Nonlinear Sigma Model(World Scientific Publ Co Pte Ltd, 2001) Baleanu, D; Güler, WThe O(3) nonlinear sigma model is investigated using multi-Hamilton-Jacobi formalism. The integrability conditions are investigated and the results are in agreement with those obtained by Dirac's method. By choosing an adequate extension of phase space we describe the transformed system by a set of three Hamilton-Jacobi equations and calculate the corresponding action.Article Citation - WoS: 3Citation - Scopus: 3Parallelization of a Molecular Dynamics Simulation of an Ion-Surface Collision(World Scientific Publ Co Pte Ltd, 2005) Özdogan, C; Güvenç, ZB; Atis, MParallel molecular dynamics simulation study of the ion-surface collision system is reported. A sequential molecular dynamics simulation program is converted into a parallel code utilizing the concept of parallel virtual machine (PVM). An effective and favorable algorithm is developed. Our parallelization of the algorithm shows that it is more efficient because of the optimal pair listing, linear scaling, and constant behavior of the internode communications. The code is tested in a distributed memory system consisting of a cluster of eight PCs that run under Linux (Debian 2.4.20 kernel). Our results on the collision system are discussed based on the speed up, efficiency and the system size. Furthermore, the code is used for a full simulation of the Ar-Ni(100) collision system and calculated physical quantities are presented.Article Citation - WoS: 6Citation - Scopus: 4Symmetries of the Dual Metrics(World Scientific Publ Co Pte Ltd, 2002) Baleanu, DIn this paper the symmetries of the dual manifold are investigated. We found the conditions when the manifold and its dual admit the same Killing vectors and Killing-Yano tensors. The dual conformal Killing vectors and dual conformal Killing-Yano tensors were investigated. In the case of an Einstein's metric g(munu) the corresponding equations for its dual were found. The examples of Kerr-Newman geometry and the separable coordinates in 1 + 1 dimensions axe analyzed in details.