Now showing items 1-18 of 18

    • Digital computation of the fractional Fourier transform 

      Haldun M. Özaktaş; Arıkan, Orhan; Kutay, M. A.; Bozdağı, G. (Institute of Electrical and Electronics Engineers, 1996-09)
      An algorithm for efficient and accurate computation of the fractional Fourier transform is given. For signals with time-bandwidth product N, the presented algorithm computes the fractional transform in O(NlogN) time. A ...
    • Effects of linear filter on stability and performance of human-in-the-loop model reference adaptive control architectures 

      Yousefi, Ehsan; Demir, Didem Fatma; Sipahi, R.; Yücelen, T.; Yıldız, Yıldıray (ASME, 2017)
      Model reference adaptive control (MRAC) can effectively handle various challenges of the real world control problems including exogenous disturbances, system uncertainties, and degraded modes of operations. In human-in-the-loop ...
    • EFIE and MFIE, why the difference? 

      Chew W.C.; Davis, C. P.; Warnick, K. F.; Nie, Z. P.; Hu, J.; Yan, S.; Gürel, Levent (IEEE, 2008-07)
      EFIE (electric field integral equation) suffers from internal resonance, and the remedy is to use MFIE (magnetic field integral equation) to come up with a CFIE (combined field integral equation) to remove the internal ...
    • The Fractional Fourier transform and harmonic oscillation 

      Kutay, M. A.; Haldun M. Özaktaş (Springer, 2002)
      The ath-order fractional Fourier transform is a generalization of the ordinary Fourier transform such that the zeroth-order fractional Fourier transform operation is equal to the identity operation and the first-order ...
    • Improving the accuracy of the MFIE with the choice of basis functions 

      Ergül, Özgür; Gürel, Levent (IEEE, 2004-06)
      The accuracy of the magnetic-field integral equation (MFIE) for the Method of Moments (MOM) and fast-multiple-method (FMM) solutions of the electromagnetic scattering problems modeled by abitrary planar triangulations is ...
    • Interpolating between periodicity and discreteness through the fractional Fourier transform 

      Özaktaş, H. M.; Sümbül, U. (IEEE, 2006)
      Periodicity and discreteness are Fourier duals in the same sense as operators such as coordinate multiplication and differentiation, and translation and phase shift. The fractional Fourier transform allows interpolation ...
    • Morphological subband decomposition structure using GF(N) arithmetic 

      Gürcan, Metin Nafi; Çetin, A. Enis; Gerek, Ömer, N. (IEEE, 1996-09)
      Linear filter banks with critical subsampling and perfect reconstruction (PR) property have received much interest and found numerous applications in signal and image processing. Recently, nonlinear filter bank structures ...
    • New characterizations of ℓ1 solutions to overdetermined systems of linear equations 

      Madsen, K.; Nielsen H. B.; Pınar, M. Ç. (Elsevier, 1994)
      New characterizations of the ℓ1 solutions to overdetermined system of linear equations are given. The first is a polyhedral characterization of the solution set in terms of a special sign vector using a simple property of ...
    • Object-oriented query language facilitating construction of new objects 

      Alhajj, R.; Arkun, M. E. (Elsevier, 1993)
      In object-oriented database systems, messages can be used to manipulate the database; however, a query language is still a required component of any kind of database system. In the paper, we describe a query language for ...
    • On the analyticity of functions approximated by their q-Bernstein polynomials when q > 1 

      Ostrovskii I.; Ostrovska, S. (2010)
      Since in the case q > 1 the q-Bernstein polynomials Bn,q are not positive linear operators on C[0, 1], the investigation of their convergence properties for q > 1 turns out to be much harder than the one for 0 < ...
    • On the classification of Darboux integrable chains 

      Habibullin, I.; Zheltukhina, N.; Pekcan, A. (American Institute of Physics, 2008)
      We study differential-difference equation (d/dx) t (n+1,x) =f (t (n,x),t (n+1,x), (d/dx) t (n,x)) with unknown t (n,x) depending on continuous and discrete variables x and n. Equation of such kind is called Darboux integrable, ...
    • Proper orthogonal decomposition for reduced order modeling: 2D heat flow 

      Efe, M. Ö.; Özbay, Hitay (IEEE, 2003-06)
      Modeling issues of infinite dimensional systems is studied in this paper. Although the modeling problem has been solved to some extent, use of decomposition techniques still pose several difficulties. A prime one of this ...
    • Quantum stereographic projection and the homographic oscillator 

      Hakioǧlu T.; Arik, M. (American Physical Society, 1996)
      The quantum deformation created by the stenographic mapping from S2 to C is studied. It is shown that the resulting algebra is locally isomorphic to su(2) and is an unconventional deformation of which the undeformed limit ...
    • Query model for object-oriented databases 

      Alhajj, Reda; Arkun, M. Erol (IEEE, 1993-04)
      A query language should be a part of any database system. While the relational model has a well defined underlying query model, the object-oriented database systems have been criticized for not having such a query model. ...
    • Radar cross-section study of cylindrical cavity-backed apertures with outer or inner material coating: the case of E-polarization 

      Çolak, D.; Nosich, A. I.; Altintaş, A. (IEEE, 1993)
      A dual-series-based solution is obtained for the scattering of an E-polarized plane wave from a cavity-backed aperture which is formed by a slitted infinite circular cylinder coated with absorbing material. The material ...
    • Signal recovery from partial fractional fourier transform information 

      Çetin, A. Enis; Özaktaş, H.; Özaktaş, Haldun M. (IEEE, 2004)
      The fractional Fourier transform has found many applications in signal and image processing and optics. An iterative algorithm for signal recovery from partial fractional Fourier transform information is presented. The ...
    • Teager energy based feature parameters for robust speech recognition in car noise 

      Jabloun, F.; Çetin, A. Enis (IEEE, Piscataway, NJ, United States, 1999)
      In this paper, a new set of speech feature parameters based on multirate signal processing and the Teager Energy Operator is developed. The speech signal is first divided into nonuniform subbands in mel-scale using a ...
    • Vortex lattice of a Bose-Einstein condensate in a rotating anisotropic trap 

      Oktel, M. Ö. (American Physical Society, 2004)
      The behavior of Bose-Einstein condensates (BEC) with a vortex lattice in a rotating anisotropic trap was studied. The single-particle wave functions for a rotating anisotropy trap were found by exactly diagonalizing the ...