Browsing by Subject "Stochastic processes"

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    3-D motion estimation and wireframe adaptation including photometric effects for model-based coding of facial image sequences
    (IEEE, 1994-06) Bozdağı, G.; Tekalp, A. M.; Onural, L.
    We propose a novel formulation where 3-D global and local motion estimation and the adaptation of a generic wireframe model to a particular speaker are considered simultaneously within an optical flow based framework including the photometric effects of the motion. We use a flexible wireframe model whose local structure is characterized by the normal vectors of the patches which are related to the coordinates of the nodes. Geometrical constraints that describe the propagation of the movement of the nodes are introduced, which are then efficiently utilized to reduce the number of independent structure parameters. A stochastic relaxation algorithm has been used to determine optimum global motion estimates and the parameters describing the structure of the wireframe model. Results with both simulated and real facial image sequences are provided.
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    On stability of interval matrices
    (Institute of Electrical and Electronics Engineers, 1994-02) Sezer, M. E.; Siljak, D. D.
    New sufficient, and sometimes necessary and sufficient conditions, are obtained for Schur- and Hurwitz-stability of interval matrices by relying on the concept of connective stability and M-matrices. The necessity part is broadened to include interval matrices with mixed signs of the off-diagonal elements, provided the sign patterns follow that of the Morishima matrix. The obtained results are extended to cover convex combinations of interval matrices.
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    Optimal channel switching for average capacity maximization
    (IEEE, 2014-05) Sezer, Ahmet Dündar; Gezici, Sinan; İnaltekin, H.
    Optimal channel switching is proposed for average capacity maximization in the presence of average and peak power constraints. A necessary and sufficient condition is derived in order to determine when the proposed optimal channel switching approach can or cannot outperform the optimal single channel approach, which performs no channel switching. Also, it is stated that the optimal channel switching solution can be realized by channel switching between at most two different channels. In addition, a low-complexity optimization problem is derived in order to obtain the optimal channel switching solution. Numerical examples are provided to exemplify the derived theoretical results. © 2014 IEEE.
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    Rassal matematiğin Türkiye'deki öncü ismi: Ahmet Hayri Körezlioğlu
    (Bilkent University, 2020) Aydın, Uğur; İleri, Ahmet; Keleş, Ahmet Abdullah; Dağlı, Oğuzhan; Yalvaç, Bahadır
    Matematik dalında Avrupa'nın en iyi üniversitelerinde, olasılık teorisinde döneminin en önde gelen isimlerinin talebesi olarak lisans ve lisansüstü eğitimini tamamladıktan sonra bir akademisyen olarak hayatına devam eden Hayri Körezlioğlu, uluslararası düzeyde saygın bir akademik kariyere sahip olmanın yanı sıra, rassal analize dair çalışmaların Türkiye'de sistemli bir hâl almasına da önayak olması dolayısıyla son yarım asrın en önemli Türk matematikçileri arasında yer almaktadır. Bu makalede, Körezlioğlu'nun eğitim ve çalışma hayatı ile birlikte Türkiye'deki birtakım girişimleri incelenerek kendisinin Türk matematiğine katkıları ele alınacaktır.