WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653

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Now showing 1 - 10 of 215
  • Conference Object
    Covariance Features for Trajectory Analysis
    (Institute of Electrical and Electronics Engineers Inc., 2016) Karadeniz, T.; Maras, H.H.
    In this work, we aimed to demonstrate that covariance estimation methods can be used for trajectory classification. We have shown that, features obtained via shrunk covariance estimation are suitable for describing trajectories. We have arrived to the conclusion that, when compared to Dynamic Time Warping, the explained technique is faster and may yield more accurate results. © 2017 Elsevier B.V., All rights reserved.
  • Article
    Explicit Commutativity and Stability Theories for Second-Order Heun's LTVSs
    (World Scientific Publ Co Pte Ltd, 2025) Ibrahim, Salisu; Baleanu, Dumitru
    This paper derived and proved the simplex explicit commutativity theories and conditions for second-order linear time-varying systems (LTVSs) with both zero and nonzero initial conditions (ICs). We consider Heun's LTVS as a case study to verify the explicit commutative results, which were supported by simulation. Furthermore, we investigate the sensitivity of Heun's LTVS, the robustness of Heun's LTVS, the stability of Heun's LTVS, the effects due to disturbance on Heun's LTVS and the problem associated with commutativity of Heun's LTVS. These findings will tackle many problems related to the commutativity theory, the stability of LTVS, design and behavior of control systems, which have made an essential contribution and play a vital role in science and engineering. By considering a sinusoid of amplitude 5, bias -3 and frequency 7, with parameters c2,c1,c0 and an arbitrary choosing initial time (IT) t0 to be and also the initial states yA(0),yB(0),yA '(0),yB '(0), several quantitative results obtained by simulation show that the Heun's LTVSs AB and BA give the same output response, AB and BA are commutative under certain conditions and proved to be unstable numerically. Moreover, the quantitative results proved that the Heun's LTVSs AB and BA are very sensitive toward changes in ICs and parameters. Disturbance between the connections also affects the systems AB and BA, these give different responses as a result of tampering with the conditions, hence commutativity is not satisfied. Several examples have been given to support our fact explicitly and numerically. However, the explicit commutativity and stability for Heun's LTVS have not been in the literature yet, and this paper presents it for the first time. The results are well verified by simulation and treated with Wolfram Mathematica 11.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Fractional Vector Calculus in the Frame of a Generalized Caputo Fractional Derivative
    (Univ Politehnica Bucharest, Sci Bull, 2018) Jarad, Fahd; Gambo, Yusuf Ya'u; Baleanu, Dumitru; Jarad, Fahd; Baleanu, Dumitru; Abdeljawad, Thabet; Abdeljawad, Thabet; Matematik
    The authors in [1] recently introduced a new generalized fractional derivative on AC(y)(n)[a ,b] and C-y(n)[a, b], and defined their Caputo version. This derivative contains two parameters and reduces to the classical Caputo derivatives if one of these parameters tend to certain values. From here and after, by generalized Caputo fractional derivative, we refer to the Caputo version of the generalized fractional derivative. This paper studies the generalized Caputo fractional derivative and establishes the Fundamental Theorem of Fractional Calculus (FTFC) in the sense of this derivative. The fundamental results are used in establishing some vital theorems and then applied to vector calculus.
  • Editorial
    From the Guest Editors Contemporary Modelling Methods in Heat, Mass, and Fluid Flow Special Collection of Articles
    (Vinca inst Nuclear Sci, 2017) Hristov, Jordan; Baleanu, Dumitru; Baleanu, Dumitru; Atangana, Abdon; Matematik
  • Article
    Citation - WoS: 16
    Citation - Scopus: 16
    Comparative Application of Wavelet Approaches To Absorption and Ratio Spectra for the Simultaneous Determination of Diminazene Aceturate and Phenazone in Veterinary Granules for Injection
    (Govi-verlag Pharmazeutischer verlag Gmbh, 2005) Dinç, E; Baleanu, Dumitru; Kanbur, M; Baleanu, D; Matematik
    A comparison of two wavelet approaches, Daubechies and reverse Biorthogonal, is described for the quantitative resolution of a binary mixture of diminazene aceturate (DIMA) and phenazone (PHE) in veterinary granules for injection without any chemical separation. These two approaches were specified as db4 (a = 180) and rbior3.7 (a = 125) respectively, after testing the signal analysis parameters for the overlapping absorption spectra and ratio spectra. In the first step db4 (a = 180) was applied to the original absorbance data vector of DIMA and PHE. In the second step rbio3.7 (a = 125) was applied to the ratio spectra data vectors of DIMA using the divisor PHE. The same approach was also subjected to the ratio spectra of PHE using the divisor DIMA. The db4 (a = 180) and rbior3.7 (a = 125) calibration graphs were constructed using the transformation values obtained in the wavelet domain. In the method validation, the wavelet calibration functions were tested using synthetic mixtures and the standard addition technique. The simultaneous quantitative analysis of DIMA and PHE in the commercial veterinary preparation was achieved by the elaborated methods. The assay results were compared with each other and good agreement was observed.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 5
    Exact Analytical Solutions for Nonlinear Systems of Conformable Partial Differential Equations Via an Analytical Approach
    (Univ Politehnica Bucharest, Sci Bull, 2022) Thabet, Hayman; Baleanu, Dumitru; Kendre, Subhash; Baleanu, Dumitru; Peters, James; Matematik
    Many numerical and analytical methods have been developed for solving Partial Differential Equations (PDEs) and conformable PDEs, most of which provide approximate solutions. Exact solutions, however, are vitally important in the proper understanding of the qualitative features of the concerned phenomena and processes. This paper introduces an effective analytical approach for solving nonlinear systems of conformable space-time PDEs. Moreover, the convergence theorem and error analysis of the proposed method are also shown. An essential benefit of this paper is that it yields exact analytical solutions for some nonlinear dynamical systems of conformable space-time PDEs. The Graphical representations of solutions are shown to confirm the accuracy and efficiency of the suggested method.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 2
    Motion of a Spherical Particle in a Rotating Parabola Using Fractional Lagrangian
    (Univ Politehnica Bucharest, Sci Bull, 2017) Baleanu, D.; Baleanu, Dumitru; Asad, J. H.; Alipour, M.; Blaszczyk, T.; Matematik
    In this work, the fractional Lagrangian of a particle moving in a rotating parabola is used to obtain the fractional Euler- Lagrange equations of motion where derivatives within it are given in Caputo fractional derivative. The obtained fractional Euler- Lagrange equations are solved numerically by applying the Bernstein operational matrices with Tau method. The results obtained are very good and when the order of derivative closes to 1, they are in good agreement with those obtained in Ref. [10] using Multi step- Differential Transformation Method (Ms-DTM).
  • Editorial
    Contemporary Modelling Methods in Heat, Mass, and Fluid Flow - Second Part
    (Vinca inst Nuclear Sci, 2017) Hristov, Jordan; Baleanu, Dumitru; Baleanu, Dumitru; Atangana, Abdon; Matematik
  • Article
    Citation - WoS: 11
    Numerical and Bifurcations Analysis for Multi Order Fractional Model of Hiv Infection of Cd4+t-cells
    (Univ Politehnica Bucharest, Sci Bull, 2016) Alipour, Mohsen; Baleanu, Dumitru; Arshad, Sadia; Baleanu, Dumitru; Matematik
    In this paper, we solve the dynamical system of HIV infection of CD4(+) T cells within the multi-order fractional derivatives. The Bernstein operational matrices in arbitrary interval [a,b] are applied to obtain the approximate analytical solution of the model. In this way, the fractional differential equations are reduced to an algebraic easily solvable system. The obtained solutions are accurate and the method is very efficient and simple in implementation. With the help of bifurcation analysis, we acquired the critical value of viral death rate, that is, if viral death rate is greater than the critical value then level of virus particles starts to decline and thus free virus will eventually eliminate and patient is cured. Further, we found the threshold for viral infection rate analytically, which assures the stability of uninfected equilibrium and virus will ultimately eradicate.
  • Article
    Design of a Novel Converter Between Li-Ion Battery and Supercapacitor To Feed Synthetic Aperture Radar Loads for Satellite Applications
    (int Journal Renewable Energy Research, 2020) Tulay, Gencer; İskender, İres; Iskender, Ires; Elektrik-Elektronik Mühendisliği
    For satellite applications the active duty life of a satellite depends mainly on the battery lifespan. The charging or discharging current has an important role in useful life of batteries. For this purpose, the converters used in power supplies including batteries should be accurately designed such that the large current of batteries can be prevented. The power converter proposed in this paper is used to transfer energy from battery to supercapacitor when SAR (Synthetic Aperture Radar) load is active. Accordingly, the lifespan of battery and hence the lifespan of satellite will be extended. Parallel to preventing the large discharging current of batteries the proposed converter has another important property such that it is able to vary the input voltage without having any stability problems. The operating performance of the converter that is composed of Weinberg and Buck converters is analyzed using PSpice software and the results of simulations are verified through experiments. The results show that how well the converter operates satisfying the conditions required for satellite applications.