2019-10-22T13:11:16Z http://www.kjm-math.org/?_action=export&rf=summon&issue=5580
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Stability Results for Neutral Integro-Differential Equations with Multiple Functional Delays Ernest Yankson Necessary and sufficient conditions for the zero solution of the nonlinear neutral integro-differential equation<br />begin{eqnarray*}<br />&&frac{d}{dt}Big(r(t)Big[x(t)+Q(t, x(t-g_1(t)),...,x(t-g_N(t)))Big]Big)\<br /> &&= -a(t)x(t)+ sum^{N}_{i=1}int^{t}_{t-g_i(t)}k_i(t,s)f_i(x(s))ds<br /> end{eqnarray*}<br /> to be asymptotically stable are obtained. In the process we invert the integro-differential equation and obtain an equivalent integral equation. The contraction mapping principle is used as the main mathematical tool for establishing the necessary and sufficient conditions. Stability integro-differential equation functional delay 2017 01 01 1 11 http://www.kjm-math.org/article_43831_2161050be631ca19a702fe6a0bd6d1c3.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Periodic Solutions for Third-Order Nonlinear Delay Differential Equations with Variable Coefficients Abdelouaheb Ardjouni Farid Nouioua Ahcene Djoudi In this paper, the following third-order nonlinear delay differential equation<br />with periodic coefficients%<br />begin{align*}<br />& x^{primeprimeprime}(t)+p(t)x^{primeprime}(t)+q(t)x^{prime<br />}(t)+r(t)x(t)\<br />& =fleft( t,xleft( tright) ,x(t-tau(t))right) +frac{d}{dt}gleft(<br />t,xleft( t-tauleft( tright) right) right) ,<br />end{align*}<br />is considered. By employing Green's function, Krasnoselskii's fixed point<br />theorem and the contraction mapping principle, we state and prove the<br />existence and uniqueness of periodic solutions to the third-order nonlinear<br />delay differential equation. fixed point periodic solutions third-order nonlinear delay differential equations 2017 01 01 12 21 http://www.kjm-math.org/article_44493_fca28ec0388a064bcfebffd47c16b12f.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Operators Reversing Orthogonality and Characterization of Inner Product Spaces Paweł Wójcik In this short paper we answer a question posed by Chmieliński in [Adv. Oper. Theory, 1 (2016), no. 1, 8-14].<br /> Namely, we prove that among normed spaces of dimension greater than two,<br />only inner product spaces admit nonzero linear operators which reverse the Birkhoff orthogonality. Birkhoff orthogonality orthogonality reversing mappings characterizations of inner product spaces 2017 01 01 22 24 http://www.kjm-math.org/article_44746_9f829bbb7fc2df9483fd2622f9084732.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Certain Properties of a Subclass of Univalent Functions With Finitely Many Fixed Coefficients S.Sunil Varma Thomas Rosy In this paper a new class of analytic, univalent and normalized functions with finitely many fixed coefficients is defined. Properties like coefficient condition, radii of starlikeness and convexity, extreme points and integral operators applied to functions in the class are investigated. Analytic function univalent function fixed coefficient Extreme point 2017 01 01 25 32 http://www.kjm-math.org/article_44920_245bef22255f8b0b38f19d4c0c83a25b.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 On Para-Sasakian Manifolds Satisfying Certain Curvature Conditions with Canonical Paracontact Connection Selcen Yüksel Perktaş In this article, the aim is to introduce a para-Sasakian manifold with a<br />canonical paracontact connection. It is shown that \$varphi\$-conharmonically flat,<br /> \$varphi \$-\$W_{2}\$ flat and \$varphi \$-pseudo projectively flat para-Sasakian manifolds with<br /> respect to canonical paracontact connection are all \$eta \$-Einstein<br />manifolds. Also, we prove that quasi-pseudo projectively flat<br />para-Sasakian manifolds are of constant scalar curvatures. Canonical connection paracontact metric structure normal structure 2017 01 01 33 43 http://www.kjm-math.org/article_45190_7d44a17d67db3000195bfd95cc73a650.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Approximation for a Summation-Integral Type Link Operators Arun Kajla The present article deals with the general family of summation-integral type operators. Here, we propose the Durrmeyer variant of the generalized <span>Lupaş</span> operators considered by Abel and Ivan (General Math. 15 (1) (2007) 21-34) and study local approximation, Voronovskaja type formula, global approximation, Lipchitz type space and weighted approximation results. Also, we discuss the rate of convergence for absolutely continuous functions having a derivative equivalent with a function of bounded variation. Global approximation Rate of convergence Modulus of continuity bounded variation 2017 01 01 44 60 http://www.kjm-math.org/article_45322_725917aec0e6b1c459fe81fc2e4d7411.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Ostrowski's Inequality for Functions whose First Derivatives are \$s\$-Preinvex in the Second Sense Badreddine Meftah In this paper, we establish some new Ostrowski type inequalities for<br />functions whose first derivatives are \$s\$-preinvex in the second sense. Ostrowski inequality midpoint inequality H"{o}lder inequality power mean inequality preinvex functions \$s\$-preinvex functions 2017 01 01 61 80 http://www.kjm-math.org/article_46863_69c7dd0b531fa53298dd16c90cd3a0f8.pdf
2017-01-01 10.22034
Khayyam Journal of Mathematics Khayyam J. Math. 2017 3 1 Proximal Point Algorithms for Numerical Reckoning Fixed Points of Hybrid-Type Multivalued Mappings in Hilbert Spaces Kritsada Lerkchaiyaphum Withun Phuengrattana In this paper, we propose a new iteration process to approximate<br />minimizers of proper convex and lower semi-continuous functions and<br />fixed points of \$lambda\$-hybrid multivalued mappings in Hilbert<br />spaces. We also provide an example to illustrate the convergence<br />behavior of the proposed iteration process and numerically compare<br />the convergence of the proposed iteration scheme with the existing<br />schemes. Proximal point algorithm hybrid multivalued mapping Ishikawa iteration S-iteration Hilbert spaces 2017 01 01 81 89 http://www.kjm-math.org/article_46951_9c228d2ed70ca44facd3ac48e7b8797e.pdf