Cilt:68 Sayı:02 (2019)

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https://dspace.ankara.edu.tr/handle/20.500.12575/75722

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Browsing Cilt:68 Sayı:02 (2019) by Title

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    [1,2]-Complementary connected domination number of graphs-III
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Mahadevan, G.; Renuka, K.; Other; Other
    A set S⊆V(G) in a graph G is said to be [1,2]-complementary connected dominating set if for every vertex v∈V-S, 1≤|N(v)∩S|≤2 and is connected. The minimum cardinality of [1,2]-complementary connected dominating set is called [1,2]-complementary connected domination number and is denoted by γ_{[1,2]cc}(G). In this paper, we investigate 3-regular graphs on twelve vertices for which γ_{[1,2]cc}(G)=χ(G)=3.
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    A mathematical model of Hepatitis B transmission in Turkey
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Gölgeli, Meltem; Other; Other
    Hepatitis B infection is one of the serious viral infections that is treating the global health. Turkey has an intermediate endemicity for hepatitis B. In this study, a classical SIR model for hepatitis B virus (HBV) transmission is proposed and analyzed. Based on the available data of Republic of Turkey Ministry of Health, associated parameters are estimated and the fitted model is shown by appropriate simulations. The basic reproductive number is obtained by using the estimated parameters. Finally, we discuss the sensitivity of parameters and the effect of changes of parameters in the spread of disease.
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    A new result for weighted arithmetic mean summability factors of infinite series involving almost increasing sequences
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Yıldız, Şebnem; Other; Other
    In this paper, a known theorem dealing with weighted mean summability methods of non-decreasing sequences has been generalized for |A,p_{n};δ|_{k} summability factors of almost increasing sequences. Also, some new results have been obtained concerning |N,p_{n}|_{k}, |N,p_{n};δ|_{k} and |C,1;δ|_{k} summability factors.
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    A new subclass of uniformly spirallike functions with fixed coefficients
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Balachandar, Geetha; Other; Other
    In this paper a new subclass of uniformly spirallike functions is defined and several properties like coefficient estimate, closure theorems, distortion theorems, radii of starlikeness and convexity are studied.
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    A note on dominator chromatic number of line graph and jump graph of some graphs
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Kalaivani, R.; Vijayalakshmi, D.; Other; Other
    A dominator coloring is a coloring of the vertices of a graph such that every vertex is either alone in its color class or adjacent to all vertices of at least one other color class. In this paper, we obtain the dominator chromatic number for the Line graph of some graphs, Central graph of Line graph of Star graph and Central graph of Line graph of Double Star graph. And also we obtain the dominator chromatic number for J(S_{n}),J(C_{n}) and J(K_{1,n,n,n}) respectively.
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    A note on harmonic maps of statistical manifolds
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Şimşir, Fatma Muazzez; Other; Other
    We show an existence and uniqueness result for a class of maps from a flat statistical manifold into a Riemannian manifold in a given homotopy class when the target Riemannian manifold is of negative sectional curvature under a global topological non-triviality condition. We also show that due to dualistic structure of the domain manifold the result is still valid in dual coordinates.
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    A numerical solution study on singularly perturbed convection-diffusion nonlocal boundary problem
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Arslan, Derya; Çakır, Musa; Other; Other
    This important numerical method is given for the numerical solution of singularly perturbed convection-diffusion nonlocal boundary value problem. First, the behavior of the exact solution is analyzed, which is needed for analysis of the numerical solution in later sections. Next, uniformly convergent finite difference scheme on a Shishkin mesh is established, which is based on the method of integral identities with the use exponential basis functions and interpolating quadrature rules with weight and remainder term in integral form. It is shown that the method is first order accurate expect for a logarithmic factor, in the discrete maximum norm. Finally, the numerical results are presented in table and graphs, and these results reveal the validity of the theoretical results of our method.
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    A simulation study of the Bayes estimator for parameters in Weibull distribution
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Babacan, Esin Köksal; Kaya, Samet; İstatistik; Fen Fakültesi
    The Weibull distribution is one of the most popular distributions in analyzing the lifetime data. In this study, we consider the Bayes estimators of the scale and shape parameters of Weibull distribution under the assumptions of gamma priors and squared error loss function. While computing the Bayes estimates for a Weibull distribution, the continuous conjugate joint prior distribution of the shape and scale parameters does not exist and the closed form expressions of the Bayes estimators cannot be obtained. In this study first we will consider the Bayesian inference of the scale parameter under the assumption that the shape parameter is known. We will assume that the scale parameter has a gamma prior. Under these assumptions Bayes estimate can be obtained in explicit form. When both the parameters are unknown, the Bayes estimates cannot be obtained in closed form. In this case, we will assume that the scale parameter has the gamma prior, and the shape parameter also has the gamma prior and they are independently distributed. We will use the Lindley approximation to obtain the approximate Bayes estimators. Under these assumptions, we will compute approximate Bayes estimators and compare with the maximum likelihood estimators by Monte Carlo simulations.
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    Algebraic structure of square matrices over residuated lattices
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Saeid, Arsham Borumand; Eslami, E.; Balaei, S.; Other; Other
    In this paper, we introduce the algebra Mnn(L) of square matrices over residuated lattice L. The operations are induced by the corresponding operations of L. It is shown that the defined algebra behaves like a residuated lattice, but there are some slight differences. The properties of this algebra with respect to special residuated lattices are investigated. The notions of filter and ideal together with their roles are specified.
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    Algorithmic approach of cordial labeling on Cartesian product between balanced bipartite graph and path
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Ghosy, Sumonta; Pal, Anita; Other; Other
    Cordial labeling is one of the useful labeling in the realm of graph labeling. For the graph G=(V,E) vertex set V is label by {0,1}, where labeling of edge set E calculated by absolute difference between the end vertices labeling with the restriction that number of vertices label by 0 and number of vertices label by 1, their absolute difference not exceeding 1. If similar restriction will follow for edge also then the labeling technique is known as cordial labeling and the graph which admits cordial labeling is known as cordial graph. In this paper we want to apply cordial labeling on a complex graph structure which we obtained by Cartesian product between complete bipartite graph(Balanced bipartite graph) K_{n,n} and path P_{r}. We also propose three algorithm to label the above said graph by cordial labeling. We have analyse the time complexity of each algorithm and which is super-linear.
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    (alpha,m1,m2)-convexity and some inequalities of Hermite-Hadamard type
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Kadakal, Huriye; Other; Other
    In this paper, we introduce a new class of extended (alpha;m1;m2)-convex functions. Some algebraic properties of these class functions have been investigated. Some new Hermite-Hadamard type inequalities are derived. Results represent signicant refinement and improvement of the previous results. Also, the author establish a new integral identity and, by this identity, Hölder's and power mean inequality, discover some new Hermite-Hadamard type inequalities for functions whose first derivatives are (alpha;m1;m2)-convex. Our results are new and coincide with the previous results in special cases.
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    An almost orthosymmetric bilinear map
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Yılmaz, Ruşen; Other; Other
    In this paper, as a generalization of the concept of pseudo-almost f-algebra, we define a new concept of almost orthosymmetric bilinear map on a vector lattice and prove that the Arens triadjoint of a positive almost orthosymmetric bilinear map is positive almost orthosymmetric.This also extends results on the order bidual of pseudo-almost f-algebras.
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    Approximately gamma-rings in proximal relator spaces
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Uçkun, Mustafa; Other; Other
    This article introduces approximately gamma-rings, approximately gamma- ideals and approximately gamma-rings of all descriptive approximately cosets by considering new operations on the set of all descriptive approximately cosets. Afterwards, some properties of approximately gamma-rings and gamma-ideals were given.
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    Approximation by Nörlund and Riesz means in weighted Lebesgue space with variable exponent
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Testici, Ahmet; Other; Other
    We investigate the approximation properties of Nörlund and Riesz means of trigonometric Fourier series are investigated in the subset of weighted Lebesgue space with variable exponent.
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    Approximation properties of Bernstein-Kantorovich type operators of two variables
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Karahan, Döne; İzgi, Aydın; Other; Other
    In this study, the generalized Bernstein-Kantorovich type operators are introduced and some approximation properties of these operators are studied in the space of continuous functions of two variables on a compact set . The convergence rate of these operators are obtained by means of the modulus of continuity. The Voronovskaya type theorem is given and some differential properties of these operators are proved.
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    Approximation properties of modified q-Bernstein-Kantorovich operators
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Acu, Ana Maria; Agrawal, Purshottam; Kumar, Dharmendra; Other; Other
    In the present paper we define a q-analogue of the modified Bernstein-Kantorovich operators introduced by Ozarslan and Duman (Numer. Funct. Anal. Optim. 37:92-105,2016). We establish the shape preserving properties of these operators e.g. monotonicity and convexity and study the rate of convergence by means of Lipschitz class and Peetre's K-functional and degree of approximation with the aid of a smoothing process e.g Steklov mean. Further, we introduce the bivariate case of modified q-Bernstein-Kantorovich operators and study the degree of approximation in terms of the partial and total modulus of continuity and Peetre's K-functional. Finally, we introduce the associated GBS (Generalized Boolean Sum) operators and investigate the approximation of the Bogel continuous and Bogel differentiable functions by using the mixed modulus of smoothness and Lipschitz class.
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    Automatic structure for generalized Bruck-Reilly ∗-extension of a monoid
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Karpuz, Eylem Güzel; Other; Other
    In the present paper, we study the automaticity of generalized Bruck-Reilly ∗-extension of a monoid. Under some certain situations, we prove that the automaticity of the monoid implies the automaticity of the generalized Bruck-Reilly ∗-extension of this monoid.
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    Baues cofibration for quadratic modules of Lie algebras
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Yılmaz, Koray; Yılmaz, Elis Soylu; Other; Other
    In this paper; free quadratic modules and totally free ojects in the category of quadratic modules consructed over Lie algebras. We use the free quadratic modules of Lie algebras to show that the category quadratic module of lie algebras is a cofibration category by means of Baues.
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    C-class functions on some coupled fixed point theorems in partially ordered S-metric spaces
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Gupta, Vishal; Ansari, Arslan Hojat; Mani, Naveen; Other; Other
    In this paper, we prove fixed point results employing mixed weakly monotone maps, C-class functions and altering distance function in the framework of S-metric space. Here, integral application has additionally been given.
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    C^{∗}-algebra-valued rectangular b-metric spaces and some fixed point theorems
    (Ankara Üniversitesi Fen Fakültesi, 2019-08-01) Kalpana, G.; Tasneem, Z. Sumaiya; Other; Other
    The concept of C^{∗}-algebra-valued rectangular b-metric spaces is introduced as a generalization of C^{∗}-algebra-valued b-metric spaces. An analogue of Banach contraction principle and Kannan's fixed point theorem is proved in this space. As applications, existence and uniqueness results for a type of operator equation is given.