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Yayımcı "Elsevier Science Bv" için Elektronik ve Haberleşme Mühendisliği Bölümü listeleme

Yayımcı "Elsevier Science Bv" için Elektronik ve Haberleşme Mühendisliği Bölümü listeleme

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  • A hybrid Maliuzhinets/PO method for diffraction problems by impedance wedges 
    Umul, Yusuf Ziya (Elsevier Science Bv, 2011-09-01)
    The solution of Maliuzhinets of the diffraction problem of waves by an impedance wedge is transformed into a physical optics integral. The resultant expression is suitable for the investigation of various diffraction ...
  • A new representation of the Kirchhoffs diffraction integral 
    Umul, Yusuf Ziya (Elsevier Science Bv, 2013-03-15)
    The diffraction integral of Kirchhoff is rearranged according to its integral boundaries. The new approach is based on the theory of the edge dislocation waves and provides a more correct field representation for the ...
  • A simple analytical EAM model for some bcc metals 
    Dursun, İbrahim H.; Güvenç, Ziya B.; Kasap, E. (Elsevier Science Bv, 2010-05)
    An analytical embedded atom method which can treat bcc transition metal iron has been developed. In this model, a new potential was presented and a modified term has been introduced to fit the negative Cauchy pressure P-C ...
  • Application of equivalent structure constant in scintillations and BER found for non-Kolmogorov spectrum 
    Baykal, Yahya; Gerçekçioğlu, Hamza (Elsevier Science Bv, 2014-01-01)
    The evaluation of system parameters in the non-Kolmogorov turbulent atmosphere involves the structure constant valid at the relevant non-Kolmogorov power law exponent. In some of the existing results, the comparisons of ...
  • Average transmittance in non-Kolmogorov turbulence 
    Ata, Yalçın; Baykal, Yahya; Gerçekçioğlu, Hamza (Elsevier Science Bv, 2013-09-15)
    Average transmittance in non-Kolmogorov turbulence is evaluated. Our recently published equivalent structure constant formulation is employed in our numerical evaluations. At the fixed propagation distance and wavelength, ...
  • BER of annular and flat-topped beams in non-Kolmogorov weak turbulence 
    Gerçekçioğlu, Hamza; Baykal, Yahya (Elsevier Science Bv, 2013-01-01)
    The average bit error rate (BER) of multi-Gaussian beams in non-Kolmogorov weak turbulence is examined. For each specific incidence of annular and flat-topped optical beam, a power law of non-Kolmogorov spectrum is found ...
  • BER of annular and flat-topped beams in strong turbulence 
    Gerçekçioğlu, Hamza; Baykal, Yahya (Elsevier Science Bv, 2013-07-01)
    The average bit error rate (< BER >) of annular and flat-topped beams are evaluated in strong turbulence. In this respect, our earlier results on the scintillation indices obtained by the unified Rytov method are employed ...
  • Boundary diffraction wave theory of resistive surfaces with edge discontinuities 
    Umul, Yusuf Ziya (Elsevier Science Bv, 2011-10-15)
    The line integral of the boundary diffraction wave theory is derived by considering the exact diffracted fields of a resistive half-plane. The line integral is generalized for arbitrary resistive surface with edge ...
  • Coherence length in non-Kolmogorov satellite links 
    Baykal, Yahya (Elsevier Science Bv, 2013-11-01)
    Behavior of the coherence length in non-Kolmogorov satellite links is investigated. Equivalent structure constants for non-Kolmogorov spectra are employed in order to make relevant comparisons for different non-Kolmogorov ...
  • Complex degree of coherence and power moments of cylindrical sinc Gaussian beam 
    Eyyuboğlu, Halil T. (Elsevier Science Bv, 2015-12-01)
    Complex degree of coherence and power moment aspects of cylindrical sinc Gaussian beam are investigated. To do this, we have used the random phase screen approach. It is seen that on the source plane, cylindrical sinc ...
  • Diffraction of waves by a perfectly conducting half-plane between two dielectric media 
    Umul, Yusuf Ziya (Elsevier Science Bv, 2014-01-01)
    The scattered fields by a perfectly conducting half-plane, located at the interface of two dielectric media, are investigated. The diffracted fields are defined with novel reflection and transmission coefficients that are ...
  • Diffraction of waves by a resistive half-plane 
    Umul, Yusuf Ziya (Elsevier Science Bv, 2014-07-15)
    The scattered waves by a resistive half-plane are investigated with defining reflection and transmission coefficients for the diffracted waves. The coefficients are determined according to suitable conditions that are ...
  • Effects of extremely strong turbulent medium on scintillations of partially coherent annular and flat-topped Gaussian beams 
    Öztan, Mehmet A.; Baykal, Yahya; Nakiboğlu, Cem (Elsevier Science Bv, 2012-03-15)
    Scintillation index of partially coherent annular and partially coherent flat-topped Gaussian beams propagating in horizontal links is found at the receiver origin when these beams propagate in extremely strong atmospheric ...
  • Fall detection using single-tree complex wavelet transform 
    Yazar, Ahmet; Keskin, Furkan; Töreyin, Behçet Uğur; Çetin, A. Enis (Elsevier Science Bv, 2013-11-01)
    The goal of Ambient Assisted Living (AAL) research is to improve the quality of life of the elderly and handicapped people and help them maintain an independent lifestyle with the use of sensors, signal processing and ...
  • Field correlations of annular beams in extremely strong turbulence 
    Baykal, Yahya; Cai, Yangjian; Ji, Xiaoling (Elsevier Science Bv, 2012-10-01)
    The field correlations of annular beams are formulated when the atmosphere assumes extremely strong turbulence. Thicker and larger ring sized annular beams are found to exhibit larger absolute field correlations. For the ...
  • Hypergeometric Gaussian beam and its propagation in turbulence 
    Eyyuboğlu, Halil T.; Cai, Yangjian (Elsevier Science Bv, 2012-10-01)
    We study propagation characteristics of hypergeometric Gaussian beam in turbulence. In this context, we formulate the receiver plane intensity using extended Huygens-Fresnel integral. From the graphical results, it is seen ...
  • Non-Kolmogorov spectrum scintillation aspects of dark hollow and flat topped beams 
    Eyyuboğlu, Halil T.; Cai, Yangjian (Elsevier Science Bv, 2012-03-15)
    The scintillation aspects of dark hollow (DH) and fiat topped (FT) beams propagating in the turbulent atmosphere containing the non-Kolmogorov power spectrum are investigated. It is found that low scintillations will occur ...
  • Performance analysis of M-ary pulse position modulation in strong oceanic turbulence 
    Gökçe, Muhsin Caner; Baykal, Yahya; Ata, Yalçın (Elsevier Science Bv, 2018-11-15)
    In this paper, we consider an underwater wireless optical communication (UWOC) system which consists of an M-ary pulse position modulated (PPM) Gaussian optical beam at the transmitter and an avalanche photodiode (APD) at ...
  • Physical optics theory for the scattering of waves by an impedance strip 
    Umul, Yusuf Ziya (Elsevier Science Bv, 2011-04-01)
    The physical optics integral of the scattered waves by an impedance strip is derived by using the modified theory of physical optics. The surface currents of the physical optics integral, which was introduced for the ...
  • Radius of curvature of Bessel and modified Bessel Gaussian beams 
    Eyyuboğlu, Halil T.; Ji, Xiaoling (Elsevier Science Bv, 2013-07-01)
    We analyze the radius of curvature of Bessel Gaussian (BG) and modified Bessel Gaussian (mBG) beams. The study is based on the results of analytic derivation as well as those of the random phase screen approach. Our results ...