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Yayın tarihi için Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu listeleme

Yayın tarihi için Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu listeleme

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  • Simplified uniform theory of diffraction 
    Umul, Yusuf Ziya (Optical Soc Amer, 2005-07-01)
    Simple exponential functions that approach zero for reflection and shadow boundaries are considered to cancel the infinite values of diffraction coefficients at these regions. This method is applied to a wedge diffraction ...
  • Hermite-cosine-Gaussian laser beam and its propagation characteristics in turbulent atmosphere 
    Eyyuboğlu, Halil T. (Optical Soc Amer, 2005-08)
    Hermite-cosine-Gaussian (HcosG) laser beams are studied. The source plane intensity of the HcosG beam is introduced and its dependence on the source parameters is examined. By application of the Fresnel diffraction integral, ...
  • Diffraction by a black half plane: Modified theory of physical optics approach 
    Umul, Yusuf Ziya (Optical Soc Amer, 2005-09-19)
    The scattered fields from a black half plane which absorbs all the incoming electromagnetic energy are evaluated by defining a new modified theory of physical optics surface current. This current eliminates the reflected ...
  • Equivalent functions for the Fresnel integral 
    Umul, Yusuf Ziya (Optical Soc Amer, 2005-10-17)
    Fresnel integral is modeled with three equivalent functions. The first function is derived by considering the sum of the first term of the Fresnel integral's asymptotic expansion {(F) over cap (x)} and an exponential ...
  • 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 ...
  • 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 ...
  • Beams with arbitrary field profiles in turbulence - art. no. 652209 
    Baykal, Yahya (Spie-Int Soc Optical Engineering, 2006)
    Characteristics of optical beam incidences that have arbitrary field profiles are examined when they propagate in the turbulent atmosphere. Arbitrary source field profile is introduced by decomposing the source into ...
  • Intensity fluctuations for source arrays in turbulent atmosphere - art. no. 630308 
    Baykal, Yahya (Spie-Int Soc Optical Engineering, 2006)
    Intensity fluctuations are formulated for source arrays in weakly turbulent horizontal atmospheric links. Source array is composed of point sources separated by variable distances in the transverse source directions. Formula ...
  • Strategy creation, decomposition and distribution in particle navigation 
    Beldek, Ulaş; Leblebicioğlu, Kemal (Elsevier, 2006)
    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 ...
  • 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 ...
  • Modified theory of the physical-optics approach to the impedance wedge problem 
    Umul, Yusuf Ziya (Optical Soc Amer, 2006-02-01)
    The problem of a wedge with equal face impedances is examined with a modified theory of physical optics. The surface integral is constructed by use of the impedance boundary condition. The aperture equivalent current is ...
  • 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 ...
  • Higher order annular Gaussian laser beam propagation in free space (vol 45, art no 038002, 2006) 
    Eyyuboğlu, Halil T.; Yenice, Y. E.; Baykal, Yahya (Spie-Int Soc Optical Engineering, 2006-03)
    Propagation of higher order annular Gaussian (HOAG) laser beams in free space is examined. HOAG beams are defined as the difference of two Hermite-Gaussian (HG) beams; thus, they can be produced by subtracting a smaller ...
  • 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 ...
  • 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 ...
  • 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 ...
  • 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 ...
  • Modified Theory of Physical Optics Solution of Impedance Half Plane Problem 
    Umul, Yusuf Ziya (IEEE-Inst Electrical Electronics Engineers Inc, 2006-07)
    The scattering of electric polarized plane waves from an impedance half plane problem is examined by the method of modified theory of physical optics (MTPO). Two integrals, consisting of incident and reflected scattered ...
  • Turbo product codes based on convolutional codes 
    Gazi, Orhan; Yılmaz, Ali Özgür (Electronics Telecommunications Research Inst, 2006-08)
    In this article, we introduce a new class of product codesbased on convolutional codes, called convolutional product codes. The structure of product codes enables parallel decoding, which can significantly increase decoder ...