Arama Sonuçları

Listeleniyor 1 - 10 / 12
  • Yayın
    Strategies for the evolution of sex
    (American Institute of Physics Inc., 2001-12) Tüzel, Erkan; Sevim, Volkan; Erzan, Ayşe
    The maintenance of a macroscopic sexual population is addressed. As a scenario, the mechanism of random conversion to sex, in the presence of a constant rate of mutation is examined. This scenario is very closely related to "coevolution of cell senescence and diploid sexual reproduction in unicellular organisms." In this work, a "senescence clock" ticks off a finite lifetime for each bit string. Sexual reproduction resets the senescence of clock; unless this happens after a number of generations of cloning, the offspring stop dividing and die.
  • Yayın
    Neural network steering control algorithm for autonomous ground vehicles having signal time delay
    (SAGE Publications Ltd, 2024-03) Dinçmen, Erkin
    An adaptive neural network–based steering control algorithm is proposed for yaw rate tracking of autonomous ground vehicles with in-vehicle signal time delay. The control system consists of two neural networks: the observer neural network and the controller neural network. The observer neural network adapts itself to the system dynamics during the training phase. Once trained, the observer neural network cooperates with the controller neural network, which constantly adapts itself during the control task. In this way, an adaptive and intelligent control structure is proposed. Through simulation studies, it has been shown that while a proportional-integral-derivative type steering controller fails to perform its control task in case of steering signal delay, the proposed control algorithm manages to adapt itself according to the control problem and achieves reference yaw rate tracking. The robustness of the control algorithm according to the signal delay magnitude has been demonstrated by simulation studies. A rigorous Lyapunov stability analysis of the control algorithm is also presented.
  • Yayın
    The relationship between marital satisfaction and depression: The mediation effect of housewife burn
    (Wiley, 2023-12) Ulusoy, Ayşe Nehir; Karaköse, Selin
    [No abstract available]
  • Yayın
    The impact of expectations on the co-integration relationship between the stock and REIT markets
    (Inderscience Publishers, 2022-06-29) Ümit, Erol; Yüksel, Aydın; Yüksel, Aslı; Öztürk, Hakkı
    This paper examines if expectations have a significant impact on the co-integration relationship between stock and real estate investment trust markets. We use two widely followed expectation indicators which are the US yield spread and the expected US stock market volatility (VIX) to test this hypothesis. The US yield spread is decomposed into two components which are the expected short-term interest rate (EF) and a variable term premium (TP) using Hamilton-Kim algorithm. A dataset covering ten developed markets is used. Using co-integration score analysis our findings indicate that expected US short-term interest rates and expected US stock market volatility have a statistically significant and positive impact on the global co-integrations of different countries. This effect is especially valid in the post-global financial crisis period. The expectation-based indicators EF and VIX, however, do not seem to have a significant impact on co-integration at regional and local levels.
  • Yayın
    Optimisation of pedestrian detection system using FPGA-CPU hybrid implementation for vehicle industry
    (Inderscience Enterprises Ltd., 2019) Özcan, Ahmet Remzi; Tavşanoǧlu, Ahmet Vedat
    Improved image processing and developing technologies are rapidly expanding the application areas of image processing systems. In recent years, pedestrian detection systems have become one of the major safety technologies used in the automotive industry. This paper presents an optimised real-time pedestrian detection system using an FPGA-CPU based hybrid design. The histograms of oriented gradients (HOG) algorithm, which is extensively used for feature extraction in pedestrian detection applications, was implemented on a low-end FPGA. In the study, the original HOG descriptors are designed in low complexity without sacrificing performance. The obtained features were classified on a low-power single board computer with support vector machine (SVM). Tests with the INRIA pedestrian database show that the proposed model has high potential for use as a real-time low-cost pedestrian detection system in practice.
  • Yayın
    A mean field model near the NAC point in liquid crystals
    (Physical Soc Republic China, 2002-10) Enginer, Yücel; Salihoğlu, Selami; Yurtseven, Hamit
    In this study we obtain the phase line equations for the nematic-smectic A (NA), smectic A-smectic C (AC) and nematic-smectic C (NC) transitions using a mean field model. We fit these phase line equations to the experimental phase diagram near the Nenatic-smectic A-smectic C (NAC) point. Our calculated phase diagram agrees well with the experimental.
  • Yayın
    On extensions, Lie-Poisson systems, and dissipation
    (Heldermann Verlag, 2022-07-06) Esen, Oğul; Özcan, Gökhan; Sütlü, Serkan
    Lie-Poisson systems on the dual spaces of unified products are studied. Having been equipped with a twisted 2-cocycle term, the extending structure framework allows not only to study the dynamics on 2-cocycle extensions, but also to (de)couple mutually interacting Lie-Poisson systems. On the other hand, symmetric brackets; such as the double bracket, the Cartan-Killing bracket, the Casimir dissipation bracket, and the Hamilton dissipation bracket are worked out in detail. Accordingly, the collective motion of two mutually interacting irreversible dynamics, as well as the mutually interacting metriplectic flows, are obtained. The theoretical results are illustrated in three examples. As an infinite-dimensional physical model, decompositions of the BBGKY hierarchy are presented. As for the finite-dimensional examples, the coupling of two Heisenberg algebras, and the coupling of two copies of 3D dynamics are studied.
  • Yayın
    Discrete dynamical systems over double cross-product Lie groupoids
    (World Scientific, 2021-03) Esen, Oğul; Sütlü, Serkan
    Discrete Euler-Lagrange equations are studied over double cross product Lie groupoids. As such, a geometric framework for the local analysis of a discrete dynamical system is established. The arguments are elucidated on the local discrete dynamics of a gauge groupoid. The discrete Elroy's beanie is studied as a physical example.
  • Yayın
    Immunological response of frog (Rana ridibunda) skin exposed to continuous dark
    (Wiley-Blackwell Publishing, 2009-07) Şengezer İnceli, Meliha; Sancar Baş, Serap; Kımıran Erdem, Ayten; Kaptan, Engin; Arslan Aydoğdu, Elif Özlem; İnceli, Ahmet Levent
    [No abstract available]
  • Yayın
    Exact solution of perturbed Kdv equation with variable dissipation coefficient
    (Ministry Communicatios & High Technologies Republic Azerbaijan, 2017) Demiray, Hilmi
    In the present work we study the integrability condition for a variable coefficient Korteweg-deVries(KdV) equation. For that purpose, we first introduce some proper transformations for dependent and independent variables in such a way that the variable coefficient KdV equation reduces to the perturbed KdV equation with variable dissipation coefficient. Then, we apply the homogeneous balance (HB) method to this perturbed KdV equation to examine the integrability condition for this equation. The analysis reveals that if the dissipation coefficient function has a special structure the variable coefficient KdV equation is integrable. The progressive wave solution of evolution equation shows that the solution is unbounded and the wave amplitude decreases with time, which is to be expected from physical considerations.