Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu: Recent submissions

  • Diffraction of homogeneous and inhomogeneous plane waves by a planar junction between perfectly conducting and impedance half-planes 
    Umul, Yusuf Ziya (Optical Soc Amer, 2007-01)
    The problem of diffraction of homogeneous and inhomogeneous plane waves at the discontinuity formed by perfectly conducting and impedance half-planes is examined by the method of modified theory of physical optics (MTPO). ...
  • 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 ...
  • 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 ...
  • 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 ...
  • Scintillations of cos-Gaussian and annular beams 
    Eyyuboğlu, Halil T.; Baykal, Yahya (Optical Soc Amer, 2007-01)
    Based on the generalized beam formulation, we derive the scintillation index and selectively evaluate it for cos-Gaussian and annular beams propagating in weak atmospheric turbulence. Dependence of the scintillation index ...
  • Edge-dislocation waves in the diffraction process by an impedance half-plane 
    Umul, Yusuf Ziya (Optical Soc Amer, 2007-02)
    Edge-dislocation waves, created in the diffraction of plane waves by an impedance half-plane, are examined by the method of modified theory of physical optics. The integrals, obtained by a related technique, are decomposed ...
  • Molecular dynamics simulation of melting behaviour of small gold clusters: Au-N (N=12-14) 
    Yıldırım, Erdem Kamil; Atış, Murat; Güvenç, Ziya B. (IOP Publishing ltd, 2007-01)
    We have investigated the melting behaviour of AuN (N = 12 - 14) clusters by means of molecular dynamics simulation on the basis of the Voter - Chen version of the embedded-atom method. The melting behaviour of the clusters ...
  • Fast decodable turbo codes 
    Gazi, Orhan; Yılmaz, Ali Özgür (IEEE-Inst Electrical Electronics Engineers Inc, 2007-02)
    Decoding delay is an important consideration for the use of turbo codes in practical applications. We propose a new structure for turbo codes which is very suitable for parallel decoding. It is shown by union bound analysis ...
  • Zero state doped turbo equalizer 
    Gazi, Orhan; Yılmaz, Ali Özgür (IEEE-Inst Electrical Electronics Engineers Inc, 2007-02)
    Although iterative equalizers perform well at low signal to noise ratios, high latency is a major disadvantage for their use in practical communication systems. In this article we propose zero state doped turbo equalizers ...
  • Scintillation characteristics of cosh-Gaussian beams 
    Eyyuboğlu, Halil T.; Baykal, Yahya (Optical Soc Amer, 2007-03-01)
    By using the generalized beam formulation, the scintillation index is derived and evaluated for cosh-Gaussian beams in a turbulent atmosphere. Comparisons are made to cos-Gaussian and Gaussian beam scintillations. The ...
  • Hermite hyperbolic/sinusoidal Gaussian beams in ABCD systems 
    Eyyuboğlu, Halil T. (Elsevier GMBH, 2007)
    For a Hermite hyperbolic/sinusoidal Gaussian beam with focusing properties, passing through an arbitrarily shaped rectangular aperture on the source plane and an on-axis x-y asymmetric ABCD system, the receiver plane ...
  • 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 ...
  • Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beams in turbulent atmosphere 
    Eyyuboğlu, Halil T.; Baykal, Yahya (Optical Soc Amer, 2005-12)
    Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beam intensities in a turbulent atmosphere are investigated. The received intensity is formulated by applying the extended Huygens-Fresnel principle to generalized ...
  • 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 ...
  • Structures and melting of AgN (N = 7, 12–14) clusters 
    Atış, Murat; Aktaş, Hüseyin; Güvenç, Ziya B. (IOP Publishing ltd, 2005-12)
    We have studied the most stable structures of Ag-N (N = 7, 12, 13, 14) clusters and investigated their binding energies and melting behaviours using molecular dynamics and thermal quenching methods based on the Voter-Chen ...
  • Formulation of correlations for general-type beams in atmospheric turbulence 
    Baykal, Yahya (Optical Soc Amer, 2006-04)
    Log-amplitude and phase correlations of general-type beams are formulated in atmospheric turbulence. A general beam is described as the superposition of many sets of multimode contents, each mode being off-axis Hermite-Gaussian. ...
  • Molecular dynamics study of a thermal expansion coefficient: Ti bulk with an elastic minimum image method 
    Hundur, Yakup; Hippler, Rainer; Güvenç, Ziya B. (IOP Publishing LTD, 2006-05)
    Linear thermal expansion coefficient (TEC) of Ti bulk is investigated by means of molecular dynamics simulation. The elastic minimum image convention of periodic boundary conditions is introduced to allow the bulk to adjust ...
  • Flat topped beams and their characteristics in turbulent media 
    Eyyuboğlu, Halil T.; Arpalı, Çağlar; Baykal, Yahya (Optical Society of America, 2006-05)
    The source and receiver plane characteristics of flat topped (FT) beam propagating in turbulent atmosphere are investigated. To this end, source size, beam power and M(2) factor of source plane FT beam are derived. For a ...
  • Scintillation index of flat-topped Gaussian beams 
    Baykal, Yahya; Eyyuboğlu, Halil T. (Optical Soc Amer, 2006-01-01)
    The scintillation index is formulated for a flat-topped Gaussian beam source in atmospheric turbulence. The variations of the on-axis scintillations at the receiver plane are evaluated versus the link length, the size of ...
  • Effect of source spatial partial coherence on the angle-of-arrival fluctuations for free-space optics links 
    Baykal, Yahya; Eyyuboğlu, Halil T. (Spie-Int Soc Optical Engineering, 2006-05)
    The dependence of angle-of-arrival fluctuations on source coherence for free-space optics links in a turbulent atmosphere is examined. A monochromatic beam is taken, and the variation of the angle-of-arrival fluctuations ...