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Yayımcı "Elsevier Science" için Mühendislik Fakültesi listeleme

Yayımcı "Elsevier Science" için Mühendislik Fakültesi listeleme

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  • A density functional study of bare and hydrogenated platinum clusters 
    Sebetçi, Ali (Elsevier Science, 2006-12-11)
    We perform density functional theory calculations using Gaussian atomic-orbital methods within the generalized gradient approximation for the exchange and correlation to study the interactions in the bare and hydrogenated ...
  • A new quadrature routine for improper and oscillatory integrals 
    Sermutlu, Emre; Eyyuboğlu, Halil T. (Elsevier Science, 2007-01-01)
    In MATLAB environment, a new quadrature routine based on Gaussian quadrature rule has been developed. Its performance is evaluated for improper integrals, rapidly oscillating functions and other types of functions requiring ...
  • An investigation of hydrogen bonded neutral B4Hn (n=1-11) and anionic B4H11(-1) clusters: Density functional study 
    Böyükata, Mustafa; Özdoğan, Cem; Güvenç, Ziya B. (Elsevier Science, 2007-03-28)
    In this study, detailed analysis of the structural stability of hydrogen bonded four-atom boron clusters within the framework of density functional theory (DFT) is presented. Effects of the number of hydrogen atoms on the ...
  • Arbitrary laser beam propagation in free space 
    Arpalı, Çağlar; Baykal, Yahya; Nakiboğlu, Cem (Elsevier Science, 2009-08-15)
    The propagation of arbitrary laser beams in free space is examined. For this purpose, starting with an incident field of arbitrary field distribution, the intensity at the receiver plane is formulated via Huygens Fresnel ...
  • Compositional Dependence of Raman-Active Mode Frequencies and Line Widths in Tlıns2xse2(1-X) Mixed Crystals 
    Güler, I.; Gasanly, N. M.; Korkmaz, F. (Elsevier Science, 2014-11-01)
    The Raman spectra of mixed crystals TlInS2xSe2(1-x) have been investigated in the composition range of 0.25 <= x <= 0.75 and in the high-frequency region of 250-350 cm(-1) at room temperature. It was observed that Raman-active ...
  • Convergence of general beams into Gaussian intensity profiles after propagation in turbulent atmosphere 
    Eyyuboğlu, Halil T.; Baykal, Yahya; Sermutlu, Emre (Elsevier Science, 2006-09)
    It is shown that a general shaped laser beam will eventually approach a Gaussian average intensity profile after propagation in turbulent atmosphere. In our formulation, source field at the exit plane of the laser is taken ...
  • Diffraction of plane waves by a black wedge 
    Umul, Yusuf Ziya (Elsevier Science, 2010-02)
    The scattering of plane waves by a black wedge is examined. Two methods are considered for the solution of the problem. A closed-form series solution is derived by performing the technique of the separation of variables ...
  • Effects of adopting inflation targeting regimes on inflation variability 
    Berument, Hakan; Yüksel, Ebru (Elsevier Science, 2007-02-15)
    This paper investigates whether inflation-targeting programs have altered the pattern of inflation and its variability for five developed countries and four emerging economies implementing inflation-targeting programs. A ...
  • Estimating parameters of a multiple aoutoregressive model by the modified maximum likelihood method 
    Türker Bayrak, Özlem; Dener Akkaya, Ayşen (Elsevier Science, 2010-02)
    Abstract: We consider a multiple autoregressive model with non-normal error distributions, the latter being more prevalent in practice than the usually assumed normal distribution. Since the maximum likelihood equations ...
  • General formulation of the edge-diffracted paraxial waves 
    Umul, Yusuf Ziya (Elsevier Science, 2009-09)
    A general formula for edge-diffracted paraxial waves is derived in terms of the Fourier integral transform. It is observed that the scattered paraxial wave can be divided into components of the geometrical optics and ...
  • Generalized beams in ABCDGH systems 
    Eyyuboğlu, Halil T.; Baykal, Yahya (Elsevier Science, 2007-04-01)
    For a generalized beam at the source plane passing through co-located aperture and a propagation path consisting of an off-axis x-y asymmetric ABCDGH system, the receiver plane irradiance expression is derived using the ...
  • Minimization of scintillation index against displacement parameters 
    Eyyuboğlu, Halil T.; Gerçekçioğlu, Hamza; Baykal, Yahya (Elsevier Science, 2008-09-01)
    For sinusoidal beams, minimization of scintillation index is carried out against the displacements parameters. It is found-that x-y asymmetric cosh-Gaussian beam fulfills the requirements of such optimum beam. Our minimization ...
  • Molecular dynamics of thermal vibration effects: Ar + Ni(100) collision system 
    Hundur, Yakup; Güvenç, Büşra; Hippler, Rainer (Elsevier Science, 2010-04)
    In this work constant energy molecular dynamics simulations are achieved for investigating sputtering process of Ar + Ni(1 0 0) collision system. The Ni crystal is imitated by an embedded-atom potential, whereas the ...
  • MTPO based potential function of the boundary diffraction wave theory 
    Umul, Yusuf Ziya (Elsevier Science, 2008-09)
    A novel potential function is introduced by using the modified theory of physical optics integrals for a perfectly conducting half-plane. The function is valid for arbitrary aspects of observation. The line integration of ...
  • Off-axis-Gaussian beam intensity in random medium 
    Baykal, Yahya; Eyyuboğlu, Halil T. (Elsevier Science, 2007-01-01)
    The receiver intensity profile of an off-axis-Gaussian beam travelling in random medium is formulated. By examining the related exponential terms of this intensity expression, the rules governing the receiver plane ...
  • Parallel wavelet-based clustering algorithm on GPUs using CUDA 
    Yıldırım, Ahmet Artu; Özdoğan, Cem (Elsevier Science, 2011)
    There has been a substantial interest in scientific and engineering computing community to speed up the CPU-intensive tasks on graphical processing units (GPUs) with the development of many-core GPUs as having very large ...
  • Paraxial propagation of a partially coherent flattened Gaussian beam through apertured ABCD optical systems 
    Cai, Yangjian; Xiang, Lü; Eyyuboğlu, Halil T.; Baykal, Yahya (Elsevier Science, 2008-06-15)
    By expanding the hard aperture function into a finite sum of complex Gaussian functions, some approximate analytical formulae for the cross-spectral density of a partially coherent flattened Gaussian beam (FGB) propagating ...
  • Propagation characteristics of higher-order annular Gaussian beams in atmospheric turbulence 
    Eyyuboğlu, Halil T.; Altay Arpalı, Serap; Baykal, Yahya (Elsevier Science, 2006-02-15)
    The propagation characteristics of higher-order annular Gaussian (HOAG) beams in turbulence are investigated. From a HOAG source plane excitation, the average intensity of the receiver plane is developed analytically. This ...
  • Propagation of various dark hollow beams through an optical system in turbulent atmosphere 
    Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya (Elsevier Science, 2010-10)
    The propagation of a dark hollow beam (DHB) of circular, elliptical or rectangular symmetry through aligned and misaligned ABCD optical systems in turbulent atmosphere is investigated. Analytical propagation formulae for ...
  • Propagation properties of anomalous hollow beams in a turbulent atmosphere 
    Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya (Elsevier Science, 2008-11-01)
    Propagation of circular and elliptical anomalous hollow beams in a turbulent atmosphere is investigated in detail. Based on the extended Huygens-Fresnel integral, analytical formulae for the average irradiance of circular ...