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Yayımcı "Elsevier Science" için Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu listeleme

Yayımcı "Elsevier Science" için Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu listeleme

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  • 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 ...
  • 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 ...
  • 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 ...
  • 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 ...
  • Strategy creation, decomposition and distribution in particle navigation 
    Beldek, Ulaş; Leblebicioğlu, Kemal (Elsevier Science, 2007-02-01)
    Strategy planning is crucial to control a group to achieve a number of tasks in a closed area full of obstacles. In this study, genetic programming has been used to evolve rule-based hierarchical structures to move the ...
  • The effect of impedance boundary conditions on the potential function of the boundary diffraction wave theory 
    Umul, Yusuf Ziya; Yalçın, Uğur (Elsevier Science, 2008-01-01)
    A novel potential function of the boundary diffraction wave theory is obtained for the impedance surfaces by the asymptotic reduction of the modified theory of physical integrals. The function is expressed in terms of the ...
  • The relation between the boundary diffraction wave theory and physical optics 
    Umul, Yusuf Ziya (Elsevier Science, 2008-10-01)
    The physical optics surface integral is asymptotically reduced to a line integral along the contour of the diffracting edge. It is shown that the resultant integral can be separated into two sub-integrals which represent ...
  • Thermodynamics of small platinum clusters 
    Sebetçi, Ali; Güvenç, Ziya B.; Kökten, Hatice (Elsevier Science, 2006-03)
    Using the Voter and Chen version of an embedded atom model, derived by fitting simultaneously to experimental data of both the diatomic molecule and bulk platinum, we have studied the melting behavior of free, small platinum ...