Arama Sonuçları

Listeleniyor 1 - 3 / 3
  • Yayın
    Reductions of topologically massive gravity I: Hamiltonian analysis of second order degenerate Lagrangians
    (Amer Inst Physics, 2018-01) Uçgun, Filiz Çağatay; Esen, Oğul; Gümral, Hasan
    We present Skinner-Rusk and Hamiltonian formalisms of second order degenerate Clement and Sarioglu-Tekin Lagrangians. The Dirac-Bergmann constraint algorithm is employed to obtain Hamiltonian realizations of Lagrangian theories. The Gotay-Nester-Hinds algorithm is used to investigate Skinner-Rusk formalisms of these systems.
  • Yayın
    Cryptanalysis of Fridrich's chaotic image encryption
    (World Scientific Publishing, 2010-05) Solak, Ercan; Çokal, Cahit; Yıldız, Olcay Taner; Bıyıkoğlu, Türker
    We cryptanalyze Fridrich's chaotic image encryption algorithm. We show that the algebraic weaknesses of the algorithm make it vulnerable against chosen-ciphertext attacks. We propose an attack that reveals the secret permutation that is used to shuffle the pixels of a round input. We demonstrate the effectiveness of our attack with examples and simulation results. We also show that our proposed attack can be generalized to other well-known chaotic image encryption algorithms.
  • Yayın
    Lagrangian dynamics on matched pairs
    (Elsevier Science BV, 2017-01) Sütlü, Serkan Selçuk; Esen, Oğul
    Given a matched pair of Lie groups, we show that the tangent bundle of the matched pair group is isomorphic to the matched pair of the tangent groups. We thus obtain the Euler–Lagrange equations on the trivialized matched pair of tangent groups, as well as the Euler–Poincaré equations on the matched pair of Lie algebras. We show explicitly how these equations cover those of the semi-direct product theory. In particular, we study the trivialized, and the reduced Lagrangian dynamics on the group SL(2,C).