Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article On the Determination of the Quadratic Pencil of the Sturm-Liouville Operator With an Impulse(Pleiades Publishing Ltd, 2025) Khalili, Y.; Baleanu, D.In this work, an inverse problem for the quadratic pencil of the Sturm-Liouville operator with an impulse in the finite interval is considered. It is shown that some information on eigenfunctions at some internal point \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$b\in\left(\frac{1}{2},1\right)$$\end{document} and parts of two spectra uniquely determine the potential functions and all parameters in the boundary conditions. Moreover we prove that the potential functions on the whole interval and the parameters in the boundary conditions can be established from one spectrum and the potentials prescribed on \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left(\frac{1}{2},1\right)$$\end{document}.Article Explicit Commutativity and Stability Theories for Second-Order Heun's LTVSs(World Scientific Publ Co Pte Ltd, 2025) Ibrahim, Salisu; Baleanu, DumitruThis 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: 4Citation - Scopus: 4Fractional 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; MatematikThe 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.Article Citation - WoS: 16Citation - Scopus: 16Comparative 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; MatematikA 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: 3Citation - Scopus: 5Block Size Analysis for Discrete Wavelet Watermarking and Embedding a Vector Image as a Watermark(Zarka Private Univ, 2019) Sever, Hayri; Sever, Hayri; Senol, Ahmet; Elbasi, Ersin; Bilgisayar MühendisliğiAs telecommunication and computer technologies proliferate, most data are stored and transferred in digital format. Content owners, therefore, are searching for new technologies to protect copyrighted products in digital form. Image watermarking emerged as a technique for protecting image copyrights. Early studies on image watermarking used the pixel domain whereas modern watermarking methods convert a pixel based image to another domain and embed a watermark in the transform domain. This study aims to use, Block Discrete Wavelet Transform (BDWT) as the transform domain for embedding and extracting watermarks. This study consists of 2 parts. The first part investigates the effect of dividing an image into non overlapping blocks and transforming each image block to a DWT domain, independently. Then, effect of block size on watermark success and, how it is related to block size, are analyzed. The second part investigates embedding a vector image logo as a watermark. Vector images consist of geometric objects such as lines, circles and splines. Unlike pixel-based images, vector images do not lose quality due to scaling. Vector watermarks deteriorate very easily if the watermarked image is processed, such as compression or filtering. Special care must be taken when the embedded watermark is a vector image, such as adjusting the watermark strength or distributing the watermark data into the image. The relative importance of watermark data must be taken into account. To the best of our knowledge this study is the first to use a vector image as a watermark embedded in a host image.Article Citation - WoS: 8Citation - Scopus: 6Does Adr Listing Affect the Dynamics of Volatility in Emerging Markets(Charles Univ-prague, 2010) Umutlu, Mehmet; Umutlu, Mehmet; Altay-Salih, Aslihan; Akdeniz, Levent; İşletmeThis paper analyzes the time-series variation in the return volatility of non-US stocks from emerging markets that are cross-listed on US exchanges. Unlike previous studies in the cross-listing literature, return volatility is modeled using conditional heteroscedaslicity models. We find that firms' exposure to risks such as local and global market betas remain unchanged after cross-listing. Moreover, we do not identify notable changes in the dynamics of the volatility of cross-listed stocks after cross-listing except for leverage effects. We further show that the mean level of conditional variance is not affected after cross-listing. Thus, our results provide counter-evidence to the belief that foreign investor participation drives volatility upward.Article Citation - WoS: 1Citation - Scopus: 1Student Participation in Bologna Process: a Case Study From Turkey(Fac Teacher Education, 2014) Kahraman, Zerrin Ezgi; Kahraman, Z. Ezgi; Sakarya, Arif Orçun; Sakarya, A. Orcun; Orçun Sakarya, A.; Şehir ve Bölge Planlama; İşletmeBologna Process studies in Cankaya University's Interior Architecture Department (INAR), Turkey have been initiated in 2008. The goal of this study is to explore students' perceptions about the new programme outcomes framed with the Turkish Higher Education Qualifications Framework and to provide a set of guidelines for the Bologna Process to be implemented. A questionnaire including semi-structured questions is conducted in the data collection process. Content analysis method is used in order to examine students' perceptual outcomes. The findings of the study display that students' perceptions underline the importance of the acquisition of knowledge, skills and competences in social, economic and managerial dimensions of the professional life. Results also reveal the need of students for the acquisition and use of communicative, collaborative and interdisciplinary aspects of the profession and their expectations on both theoretical and practical contents of INAR courses. Furthermore, this study which mainly followed a student-cantered approach concluded that it is also possible to generalize new programme outcomes through the active participation of students.Article Citation - WoS: 3Citation - Scopus: 5Exact 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; MatematikMany 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: 4Citation - Scopus: 5One-Dimension Continuous Wavelet Resolution for the Simultaneous Analysis of Binary Mixture of Benazepril and Hydrochlorothiazide in Tablets Using Spectrophotometric Absorbance Data(Editura Academiei Romane, 2004) Dinç, E; Baleanu, Dumitru; Baleanu, D; MatematikOne-dimensional continuous wavelets transform (CWT) followed by a zero-crossing technique were applied to the quantitative resolution of a binary mixture of benazepril (BE) and hydrochlorothiazide (HCT) in two commercial tablet formulations. UV-spectra in the range of 210.1-300.0 nm, were recorded and transferred as vectors having 900 components into MATLAB 6.5. The analyzed signals corresponding to the above vectors were subjected to three CWT families, namely, Mexican (MEX), Haar (HA) and Daubechies3 (DAUB3) wavelets. For these three families a detailed analysis procedure was performed and we retained only those parameters creating many zero-crossing points for transformed signals. At locations where the wavelet transform of one component vanishes, the value of the mixture's transformed signal is due only to the other component. This allows rapid approximate determination of the concentrations. The above three wavelet bases provided reliable results of the analysis of the mixtures containing BE and HCT in two pharmaceutical tablet formulations.Article Citation - WoS: 6Citation - Scopus: 7Illicit Material Detection Using Dual-Energy X-Ray Images(Zarka Private Univ, 2016) Hassanpour, Reza; Hassanpour, Reza; Yazılım MühendisliğiDual energy X-ray inspection systems are widely used in security and controlling systems. The performance of these systems however, degrades with the poor performance of human operators. Computer vision based systems are of vital importance in improving the detection rate of illicit materials, while keeping false alarms at a reasonably low level. In this study, a novel method is proposed for detecting material overlapping and reconstructing multiple images by alleviating these overlaps. Evaluation tests were conducted on images taken from luggage inspection X-ray screening devices used in shopping centres. The experimental results indicate that the reconstructed images are much easier to inspect by human operators than the unprocessed original images.