Akademik Çıktılar

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Citation - Scopus: 7
On the solution of a parabolic PDE involving a gas flow through a semi-infinite porous medium
(Amsterdam, 22) Pop, Daniel N.; Vrinceanu, N.; Al-Omari, S.; Ouerfelli, N.; Baleanu, D.; Nisar, K. S.; 56389; Matematik
Taking as start point the parabolic partial differential equation with the respective initial and boundary conditions, the present research focuses onto the flow of a sample of waste-water derived from a standard/conventional dyeing process. In terms of a highly prioritized concern, meaning environment decontamination and protection, in order to remove the dyes from the waste waters, photocatalyses like ZnO or TiO2 nanoparticles were formulated, due to their high surface energy which makes them extremely reactive and attractive. According to the basics of ideal fluid, the key point is the gas flow through an ideal porous pipe consisting of nanoparticles bound one to each other, forming a porous matrix/pipe. The modeling of the gas flow through a porous media is quite valuable because of its importance in investigating the gas-solid processes. The present study is a valid contribution to the existing literature, by developing a nonstandard line method for the partial differential equation, in order to obtain a numerical solution of unsteady flow of gas through nano porous medium. Hence, the physical problem is modeled by a highly nonlinear ordinary differential equation detailed on a semi-finite domain and represents a guidance for several questions originating in the gas flow theory. The findings of this study offered a facile approach to improve an attractive issue related to materials science/chemistry, like synthesis of ZnO or TiO2 nanoparticles forming an ideal nano porous pipe with efficiency in industrial waste waters decontamination.
Citation - Scopus: 3
The confined system approximation for solving non-separable potentials in three dimensions
(1998) Taşeli, H.; Eid, R.
The Hubert space L2(ℝ3), to which the wavefunction of the three-dimensional Schrödinger equation belongs, has been replaced by L2(Ω), where Ω is a bounded region. The energy spectrum of the usual unbounded system is then determined by showing that the Dirichlet and Neumann problems in L2(Ω) generate upper and lower bounds, respectively, to the eigenvalues required. Highly accurate numerical results for the quartic and sextic oscillators are presented for a wide range of the coupling constants.
Citation - WoS: 0
A Petri Net-based inference network for design automation under nondeterminism applied to mechatronic systems
(Pergamon Press Ltd, 1998) Erden, Z; Erkmen, AM; Erden, A
This paper introduces the completed part of an ongoing research, in which a Petri Net-based design inference network is developed for the representation and analysis of the functions and their interrelationships through information flow for the conceptual design stage of mechatronic systems in order to facilitate design automation. The theoretical framework behind the network is based on transition of Hybrid Automata into Petri Nets and application of this framework is introduced by a mechatronic design example.
Citation - WoS: 2
Citation - Scopus: 3
Higher order finite element solution of the one-dimensional Schrodinger equation
(John Wiley & Sons inc, 1999) Eid, R; Eid, R
The one-dimensional Schrodinger equation has been examined by means of the confined system defined on a finite interval. The eigenvalues of the resulting bounded problem subject to the Dirichlet boundary conditions are calculated accurately to 20 significant figures using higher order shape functions in the usual isoparametric finite element method. Numerical results are given for an arbitrary polynomial potential of degree M. (C) 1999 John Wiley & Sons, Inc.
Citation - WoS: 7
Citation - Scopus: 5
Hamilton-Jacobi quantization of the finite-dimensional systems with constraints
(Editrice Compositori Bologna, 1999) Baleanu, D; Güler, Y; 56389; Matematik
The Hamiltonian treatment of constrained systems in Guler's formalism leads us to the total differential equations in many variables. These equations are integrable if the corresponding system of partial differential equations is a Jacobi system. The main aim of this paper is to investigate the quantization of the finite-dimensional systems with constraints using the canonical formalism introduced by Guler. This approach is applied for two systems with constraints and the results are in agreement with those obtained by Dirac's canonical quatization method and path integral quantization method.
Citation - WoS: 9
Quantization of Floreanini-Jackiw chiral harmonic oscillator
(Editrice Compositori Bologna, 1999) Baleanu, D; Güler, Y; 56389; Matematik
The Floreanini-Jackiw formulation for the chiral quantum mechanical system oscillator is a model of constrained theory with only second-class constraints in Dirac's classification. The covariant quantization needs an infinite number of auxiliary variables and a Wess-Zumino term. In this paper we investigate the path integral quatization of this model using Guler's canonical formalism. All variables are gauge variables in Guler's formalism. Siegel's action is obtained using Hamilton-Jacobi formulation of the systems with constraints.
Citation - Scopus: 5
Structural forms and energies of Nin, n = 12-14, clusters
(1999) Güvenç, Ziya B.; Jellınek, Julius; Güvenç, Dilek
Equilibrium structural forms of the $Ni_n$, n=12-14, clusters, as defined by an embedded-atom potential, are obtained using molecular dynamics and thermal quenching simulations. The isomers (locally stable geometric forms) are distinguished from those stationary structures that correspond to saddle points of the potential energy surface. Isomer statistics are obtained using a large number of initial quenching configurations generated along high-energy trajectories (the energies are high enough to "melt" the clusters). Probabilities of sampling the basins of attraction of the different isomers are computed and the spectra of their energies are analyzed.
Citation - WoS: 0
Citation - Scopus: 0
Lax tensors and separable coordinates in (2+1) dimensions
(inst Physics Acad Sci Czech Republic, 2000) Baleanu, D; Baskal, S; 56389; Matematik
We study the Lax tensors of the separable coordinates in (2+1) dimensions. The Lax tensors of the dual manifolds are investigated.
Citation - WoS: 10
Citation - Scopus: 6
Geometrization of the Lax pair tensors
(World Scientific Publ Co Pte Ltd, 2000) Baleanu, D; Baskal, S; 56389; Matematik
The tensorial form of the Lax pair equations are given in a compact and geometrically transparent form in the presence of Cartan's torsion tensor. Three-dimensional space-times admitting Lax tensors are analyzed in detail. Solutions to Lax tensor equations include interesting examples as separable coordinates and the Toda lattice.
Citation - WoS: 16
A general treatment of singular Lagrangians with linear velocities
(Editrice Compositori Bologna, 2000) Baleanu, D; Güler, Y; 56389; Matematik
The Hamilton-Jacobi treatment of singular systems with linear velocities is investigated. Since the rank of Hessian matrix is zero, all the generalized coordinates are independent parameters. Integrability conditions reduce the degrees of freedom. Path integral quantization is analyzed.
Citation - WoS: 12
Citation - Scopus: 14
Reactions of small Ni clusters with a diatomic molecule: MD simulation of D(2)+Ni(n) (n=7-10) systems
(Elsevier Science Bv, 2000) Durmus, P; Böyükata, M; Özçelik, S; Güvenç, ZB; Jellinek, J
The kinetics of the reactions of nickel clusters with a deuterium molecule are studied, Dissociative chemisorption probabilities of the D(2) molecule on the small Ni(n) (n=7-10) clusters are computed by a quasi-classical molecular dynamics computer simulation technique. Structures of the clusters are obtained by an embedded-atom potential, and the interaction between the D(2) and Ni(n) is modelled by an LEPS (London-Eyring-Polanyi-Sato) function (energy surface). This analysis includes the chemisorption probabilities as functions of the impact parameter and of the relative translational energy of the D(2). The corresponding reactive cross-sections for the ground state of the molecule are calculated as functions of the collision energy and the size of the cluster. The role of the size of the clusters is examined. An indirect mechanism to the reaction, which involves formation of molecular adsorption as precursors to dissociative adsorption in the low collision energy region (less than 0.1eV), is observed. Results are discussed by comparing with the other similar theoretical and experimental studies. (C) 2000 Elsevier Science B.V. All rights reserved.
Citation - WoS: 4
On the construction of the phase space of a singular system
(Editrice Compositori Bologna, 2000) Baleanu, D; Güler, Y; 56389; Matematik
In this work we present a method for obtaining the true degrees of freedom for the singular systems using the canonical transformations in the Hamilton-Jacobi formalism. The validity of our proposal has been tested by two examples of singular Lagrangians and the results are in agreement with those obtained by other methods.
Citation - WoS: 8
Citation - Scopus: 7
Sputtering yield and dynamical analysis of Ni(100) surface: A comparison of four different Ar-surface interaction potentials
(Elsevier Science Bv, 2000) Güvenç, ZB; Hundur, Y; Hippler, R
The sputtering process of the Ar + Ni(100) collision system is investigated by means of constant energy molecular dynamics simulations. The Ni(100) is mimicked by an embedded-atom potential, and the interaction between the projectile and the surface is modelled by using four different screened Coulomb type potentials. The Ni atom emission from the lattice is analysed over the range of 10-40 eV collision energy. The maximum penetration depths of Ar, probability distributions of kinetic energy of the reflected Ar, and energy of the Ar and sputtered Ni atoms in the same collision events are evaluated as functions of the impact energy and sputtering time. Further, angular distributions of the scattered Ar are obtained. The calculated sputtering yields are compared with the available theoretical and experimental data. (C) 2000 Elsevier Science B.V. All rights reserved.
Citation - Scopus: 9
Hamilton-Jacobi treatment of fields with constraints
(Editrice Compositori s.r.l., 2000) Baleanu, D.; Güler, Y.; 56389; Matematik
In this paper Güler's formalism for the systems with finite degrees of freedom is applied to the field theories with constraints. The integrability conditions are investigated and the path integral quantization is performed using the action given by Hamilton-Jacobi formulation. Proca's model is investigated in details.
Citation - WoS: 3
Citation - Scopus: 2
Symmetries of NUT-Kerr-Newman dual metrics
(Soc Italiana Fisica, 2001) Baleanu, D; 56389; Matematik
The symmetries of NUT-Kerr-Newman (NUT-KN) dual metrics are analysed. The NUT-Kerr-Newman dual spinning space is constructed in the presence of torsion.
Citation - WoS: 0
Citation - Scopus: 0
An approach to noise reduction in human skin admittance measurements
(Ieee, 2001) Kondakci, S; Kondakci, S; 102350; Bilgisayar Mühendisliği
This paper presents the development of a signal averaging algorithm for recovering excitation responses contaminated by overwhelming amount of various types of interference in skin admittance measurements. The algorithm is designed to eliminate Gaussian-distributed noise by use of a recursive approach. The process of recovering low magnitude voltage responses from highly noise-contaminated waveforms is a CPU-intensive task. In real-time measurements, iterative reconstruction algorithm is inefficient and time consuming when slow varying input waveforms are present. To increase the quality of the reconstruction a considerably large number of recursions is required. Increasing the number of recursions is appropriate for batch processing of measurement data. However, the algorithm considers measurements in real-time, whereas required quality of signal reconstruction should be kept independent from the number of recursions.
Citation - WoS: 42
Citation - Scopus: 47
Nonnormal regression. II. Symmetric distributions
(Taylor & Francis inc, 2001) Tiku, ML; Islam, MQ; Selçuk, AS
Salient features of a family of short-tailed symmetric distributions, introduced recently by Tiku and Vaughan [1], are enunciated. Assuming the error distribution to be one of this family, the methodology of modified likelihood is used to derive MML estimators of parameters in a linear regression model. The estimators are shown to be efficient, and robust to inliers. This paper is essentially the first to achieve robustness to infers. The methodology is extended to long-tailed symmetric distributions and the resulting estimators are shown to be efficient, and robust to outliers. This paper should be read in conjunction with Islam et al. [2] who develop modified likelihood methodology for skew distributions in the context of linear regression.
Citation - WoS: 14
Citation - Scopus: 14
The hamilton-jacobi treatment of supersymmetric quantum mechanics
(World Scientific Publ Co Pte Ltd, 2001) Baleanu, D; Güler, Y; 56389; Matematik
We study the Hamilton-Jacobi quantization of supersymmetric quantum mechanics. The equations of motion of the Grassmann variables are obtained from the integrability conditions. The results are in agreement with those obtained by Dirac's procedure.
Citation - WoS: 57
Citation - Scopus: 67
Spectrophotometric multicomponent analysis of a mixture of metamizol, acetaminophen and caffeine in pharmaceutical formulations by two chemometric techniques
(Pergamon-elsevier Science Ltd, 2001) Dinç, E; Baleanu, D; Onur, F; 56389; Matematik
Inverse least squares (ILS) and factor-based (principal component analysis (PCA)) techniques were proposed for the spectrophotometric multicomponent analysis of a ternary mixture consisting of metamizol, acetaminophen and caffeine, without prior separation. In these chemometric techniques, the measurements of the absorbance values were realized in the spectral range from 225 to 285 nm in the intervals of Delta lambda = 5 nm at the 13 wavelengths in the zero-order spectra of the different ternary mixtures of these active ingredients in 0.1 M HCl. The prepared calibrations of both techniques using the absorbance data and concentration matrix data sets were used to predict the concentration of the unknown concentrations of metamizol acetaminophen and caffeine in their ternary mixture. The 'MAPLE V' software was used for the numerical calculations, Mean recoveries and relative standard deviations for ILS and PCA techniques were found to be 99.8 and 1.68%, 99.9 and 1,66% for caffeine, 99.8 and 1.84%, 100.4 and 2.85% for metamizol, and 99.7 and 1.04%, 99.6 and 1.34/ for acetaminophen, respectively, for the first and second techniques. The techniques were successfully applied to two pharmaceutical formulations marketed in Turkey and results were compared with a new high-performance liquid chromatography method. (C) 2001 Elsevier Science B.V. All rights reserved.
Citation - WoS: 0
Citation - Scopus: 0
Hamilton-Jacobi quantization of constrained systems
(inst Physics Acad Sci Czech Republic, 2001) Baleanu, D; Güler, Y; 56389; Matematik
The path integral quantization of contrained systems is analysed using Hamilton-Jacobi formalism. The integrability conditions are investigated and the results are in agreement with those obtained by Dirac's method.

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