Now showing items 1-20 of 27

    • Approximate computation of DFT without performing any multiplications: application to radar signal processing 

      Arslan, Musa Tunç; Bozkurt, Alican; Sevimli, Rasim Akın; Akbaş, Cem Emre; Çetin, A. Enis (IEEE, 2014)
      In many radar problems it is not necessary to compute the ambiguity function in a perfect manner. In this article a new multiplication free algorithm for approximate computation of the ambiguity function is introduced. All ...
    • Automatic multimedia cross-modal correlation discovery 

      Pan, J.-Y.; Yang, H.-J.; Faloutsos, C.; Duygulu, Pınar (ACM, 2004-08)
      Given an image (or video clip, or audio song), how do we automatically assign keywords to it? The general problem is to find correlations across the media in a collection of multimedia objects like video clips, with colors, ...
    • Automatic Ranking of Retrieval Systems in Imperfect Environments 

      Nuray, Rabia; Can, Fazlı (ACM, 2003-07-08)
      The empirical investigation of the effectiveness of information retrieval (IR) systems requires a test collection, a set of query topics, and a set of relevance judgments made by human assessors for each query. Previous ...
    • Aviation risk perception: a comparison between experts and novices 

      Thomson, M. E.; Önkal D.; Avcioǧlu, A.; Goodwin, P. (Wiley-Blackwell Publishing, 2004)
      This article describes an exploratory investigation of the risk perceptions of experts and novices in relation to helicopter operations, under conditions where the participants are matched on various characteristics ...
    • Bound electron pairs in strongly correlated models of high-temperature superconductivity 

      Boyaci, H.; Kulik, I. O. (Natsional'na Akademiya Nauk Ukrainy, 1998)
      The ground-state energy of two electrons on a ring is calculated for the one-dimensional Hubbard model with positive and negative on-site interaction and for the contraction model with additive and multiplicative interaction ...
    • Carcinoma cell line discrimination in microscopic images using unbalanced wavelets 

      Keskin, Furkan; Suhre, Alexander; Erşahin, Tüli,; Çetin Atalay, Rengül; Çetin, A. Enis (IEEE, 2012-03)
      Cancer cell lines are widely used for research purposes in laboratories all over the world. In this paper, we present a novel method for cancer cell line image classification, which is very costly by conventional methods. ...
    • Chiral single-wall gold nanotubes 

      Senger, R. T.; Dag, S.; Çıracı, Salim (American Physical Society, 2004)
      The formation of freestanding and tip-suspended chiral-wall (n,m) nanotubes, which were composed of helical atomic strands, from gold atoms was investigated using first-principles calculations, where (n,m) notation defines ...
    • Computationally efficient wavelet affine invariant functions for shape recognition 

      Bala, E.; Çetin, A. Enis (IEEE, 2004)
      An affine invariant function for object recognition is constructed from wavelet coefficients of the object boundary. In previous works, undecimated dyadic wavelet transform was used to construct affine invariant functions. ...
    • Correlation tracking based on wavelet domain information 

      İpek, H. L.; Yılmaz, İ.; Yardımcı, Y. C.; Çetin, A. Enis (SPIE, 2004)
      Tracking moving objects in video can be carried out by correlating a template containing object pixels with pixels of the current frame. This approach may produce erroneous results under noise. We determine a set of ...
    • Dynamical correlations in Coulomb drag effect 

      Tanatar, Bilal; Davoudi, B.; Hu, B.Y.-K. (Elsevier, 2003)
      Motivated by recent Coulomb drag experiments in pairs of low-density two-dimensional (2D) electron gases, we investigate the influence of correlation effects on the interlayer drag rate as a function of temperature. We use ...
    • El yazısı belgelerde kelime tabanlı arama 

      Can, Ethem F.; Duygulu, Pınar (IEEE, 2008-04)
      Bu çalışmada el yazısı belgelerde arama yapabilmek için yeni yöntemler önerilmiştir. Bu çalışmadaki en temel varsayım ve yola çıkış noktası; her bir kelimenin resim gibi ele alınabileceği ve dolayısıyla resim arama teknikleri ...
    • Electronic structure, insulator-metal transition and superconductivity in K-ET2X salts 

      Ivanov V.A.; Ugolkova, E.A.; Zhuravlev, M.Ye.; Hakioǧlu, T. (1998)
      The electronic structure and superconductivity of layered organic materials based on the bis(ethylenedithio)tetrathiafulvalene molecule (BEDT-TTF, hereafter ET) with essential intra-ET correlations of electrons are analysed. ...
    • Existence of a metallic phase in a 1D Holstein-Hubbard model at half filling 

      Krishna, P. M.; Chatterjee, A. (Elsevier B.V., 2007)
      The one-dimensional half-filled Holstein-Hubbard model is studied using a series of canonical transformations including phonon coherence effect that partly depends on the electron density and is partly independent and also ...
    • Fast insect damage detection in wheat kernels using transmittance images 

      Çataltepe, Z.; Pearson, T.; Cetin, A. Enis (IEEE, 2004-07)
      We used transmittance images and different learning algorithms to classify insect damaged and un-damaged wheat kernels. Using the histogram of the pixels of the wheat images as the feature, and the linear model as the ...
    • Fast processing techniques for accurate ultrasonic range measurements 

      Barshan, B. (Institute of Physics Publishing, 2000)
      Four methods of range measurement for airborne ultrasonic systems - namely simple thresholding, curve-fitting, sliding-window, and correlation detection - are compared on the basis of bias error, standard deviation, total ...
    • Feedback-labelling synergies in judgmental stock price forecasting 

      Goodwin, P.; Önkal-Atay, D.; Thomson, M. E.; Pollock, A. C.; Macaulay, A. (Elsevier, 2004)
      Research has suggested that outcome feedback is less effective than other forms of feedback in promoting learning by users of decision support systems. However, if circumstances can be identified where the effectiveness ...
    • Many-body effects in the Coulomb drag between low density electron layers 

      Yurtsever, A.; Moldoveanu, V.; Tanatar, Bilal (Elsevier Science, 2003)
      Recent Coulomb drag experiments in low-density double-layer electron systems have the power of distinguishing various many-body formulations of the effective interactions. In this work we theoretically study the correlation ...
    • Markov modulated periodic arrival process offered to an ATM multiplexer 

      Akar, Nail; Arıkan, Erdal (IEEE, 1993-11-12)
      When a superposition of on/off sources is offered to a deterministic server, a particular queueing system arises whose analysis has a significant role in ATM based networks. Periodic cell generation during active times is ...
    • The off-resonant aspects of decoherence and a critique of the two-level approximation 

      Savran, K.; Hakioǧlu T.; Mese, E.; Sevinçli, H. (IOP Institute of Physics, 2006)
      Conditions in favour of a realistic multilevelled description of a decohering quantum system are examined. In this regard the first crucial observation is that the thermal effects, contrary to the conventional belief, play ...
    • Plasmon dispersion and damping in double-layer electron systems 

      Davoudi, B.; Tanatar, Bilal (Elsevier Science Ltd, Exeter, United Kingdom, 2000)
      We use dynamical local-field corrections to study the plasmon dispersion and damping in double-layer electron systems. The wave vector and frequency-dependent local-fields describing the exchange-correlation effects are ...