DSpace Community: 2010
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Dense Subdifferentiability and Trustworthiness for Arbitrary Subdifferentials
http://hdl.handle.net/10525/2711
Title: Dense Subdifferentiability and Trustworthiness for Arbitrary Subdifferentials<br/><br/>Authors: Jules, Florence; Lassonde, Marc<br/><br/>Abstract: We show that the properties of dense subdifferentiability and of trustworthiness are equivalent for any subdifferential satisfying a small set of natural axioms. The proof relies on a remarkable property of the subdifferential of the inf-convolution of two (non necessarily convex) functions. We also show the equivalence of the dense subdifferentiability property with other basic properties of subdifferentials such as a weak* Lipschitz Separation property, a strong Compact Separation property and a Minimal property for the analytic approximate subdifferential of Ioffe.<br/><br/>Description: 2000 Mathematics Subject Classification: 49J52, 49J50, 58C20, 26B09.Plus-Minus Property as a Generalization of the Daugavet Property
http://hdl.handle.net/10525/2710
Title: Plus-Minus Property as a Generalization of the Daugavet Property<br/><br/>Authors: Shepelska, Varvara<br/><br/>Abstract: It was shown in [2] that the most natural equalities valid for every rank-one operator T in real Banach spaces lead either to the Daugavet equation ||I+T|| = 1 + ||T|| or to the equation ||I − T|| = ||I+T||. We study if the spaces where the latter condition is satisfied for every finite-rank operator inherit the properties of Daugavet spaces.<br/><br/>Description: 2000 Mathematics Subject Classification: Primary 46B20. Secondary 47A99, 46B42.Local Energy Decay in Even Dimensions for the Wave Equation with a Time-Periodic Non-Trapping Metric and Applications to Strichartz Estimates
http://hdl.handle.net/10525/2709
Title: Local Energy Decay in Even Dimensions for the Wave Equation with a Time-Periodic Non-Trapping Metric and Applications to Strichartz Estimates<br/><br/>Authors: Kian, Yavar<br/><br/>Abstract: We obtain local energy decay as well as global Strichartz estimates for the solutions u of the wave equation ∂t2 u-divx(a(t,x)∇xu) = 0, t ∈ R, x ∈ Rn, with time-periodic non-trapping metric a(t,x) equal to 1 outside a compact set with respect to x. We suppose that the cut-off resolvent Rχ(θ) = χ(U(T, 0)− e−iθ)−1χ, where U(T, 0) is the monodromy operator and T the period of a(t,x), admits an holomorphic continuation to {θ ∈ C : Im(θ) ≥ 0}, for n ≥ 3, odd, and to {θ ∈ C : Im(θ) ≥ 0, θ ≠ 2kπ − iμ, k ∈ Z, μ ≥ 0} for n ≥ 4, even, and for n ≥ 4 even Rχ(θ) is bounded in a neighborhood of θ = 0.<br/><br/>Description: 2000 Mathematics Subject Classification: 35B40, 35L15.Selections, Paracompactness and Compactness
http://hdl.handle.net/10525/2708
Title: Selections, Paracompactness and Compactness<br/><br/>Authors: Choban, Mitrofan M.; Mihaylova, Ekaterina P.; Nedev, Stoyan I.<br/><br/>Abstract: In the present paper the Lindelöf number and the degree of compactness of spaces and of the cozero-dimensional kernel of paracompact spaces are characterized in terms of selections of lower semi-continuous closed-valued mappings into complete metrizable (or discrete) spaces.<br/><br/>Description: 2000 Mathematics Subject Classification: 54C60, 54C65, 54D20, 54D30.On the Character of Growth of a Non-Contracting Semigroup
http://hdl.handle.net/10525/2707
Title: On the Character of Growth of a Non-Contracting Semigroup<br/><br/>Authors: Rozumenko, O. V.<br/><br/>Abstract: An estimation of the growth of a non-contracting semigroup Zt = exp(itA) where A is a non-dissipative operator with a two-dimensional imaginary component is given. Estimation is given in terms of the functional model in de Branges space.<br/><br/>Description: 2000 Mathematics Subject Classification: 47A45.Wave Operators for Defocusing Matrix Zakharov-Shabat Systems with Pnonvanishing at Infinity
http://hdl.handle.net/10525/2706
Title: Wave Operators for Defocusing Matrix Zakharov-Shabat Systems with Pnonvanishing at Infinity<br/><br/>Authors: Demontis, Francesco; der Mee, Cornelis van<br/><br/>Abstract: In this article we prove that the wave operators describing the direct scattering of the defocusing matrix Zakharov-Shabat system with potentials having distinct nonzero values with the same modulus at ± ∞ exist, are asymptotically complete, and lead to a unitary scattering operator. We also prove that the free Hamiltonian operator is absolutely continuous.<br/><br/>Description: 2000 Mathematics Subject Classification: Primary: 34L25; secondary: 47A40, 81Q10.Oscillation Criteria of Second-Order Quasi-Linear Neutral Delay Difference Equations
http://hdl.handle.net/10525/2705
Title: Oscillation Criteria of Second-Order Quasi-Linear Neutral Delay Difference Equations<br/><br/>Authors: Thandapani, E.; Pandian, S.; Revathi, T.<br/><br/>Abstract: The oscillatory and nonoscillatory behaviour of solutions of the second order quasi linear neutral delay difference equationΔ(an | Δ(xn+pnxn-τ)|α-1 Δ(xn+pnxn-τ) + qnf(xn-σ)g(Δxn) = 0where n ∈ N(n0), α > 0, τ, σ are fixed non negative integers, {an}, {pn}, {qn} are real sequences and f and g real valued continuous functions are studied. Our results generalize and improve some known results of neutral delay difference equations.<br/><br/>Description: 2000 Mathematics Subject Classification: 39A10.Units of F5kD10
http://hdl.handle.net/10525/2704
Title: Units of F5kD10<br/><br/>Authors: Gildea, Joe<br/><br/>Abstract: The Structure of the Unit Group of the Group Algebra of the group D10 over any field of characteristic 5 is established in terms of split extensions of cyclic groups.<br/><br/>Description: 2000 Mathematics Subject Classification: 20C05, 16U60, 16S84, 15A33.Warped Product CR-Submanifolds in Lorentzian para Sasakian Manifolds
http://hdl.handle.net/10525/2703
Title: Warped Product CR-Submanifolds in Lorentzian para Sasakian Manifolds<br/><br/>Authors: Uddin, Siraj<br/><br/>Abstract: Many research articles have recently appeared exploring existence or non existence of warped product submanifolds in known spaces (cf. [2, 5, 8]). The objective of the present paper is to study the existence or non-existence of contact CR-warped products in the setting of LP-Sasakian manifolds.<br/><br/>Description: 2000 Mathematics Subject Classification: 53C15, 53C40, 53C42.Low Volatility Options and Numerical Diffusion of Finite Difference Schemes
http://hdl.handle.net/10525/2702
Title: Low Volatility Options and Numerical Diffusion of Finite Difference Schemes<br/><br/>Authors: Milev, Mariyan; Tagliani, Aldo<br/><br/>Abstract: In this paper we explore the numerical diffusion introduced by two nonstandard finite difference schemes applied to the Black-Scholes partial differential equation for pricing discontinuous payoff and low volatility options. Discontinuities in the initial conditions require applying nonstandard non-oscillating finite difference schemes such as the exponentially fitted finite difference schemes suggested by D. Duffy and the Crank-Nicolson variant scheme of Milev-Tagliani. We present a short survey of these two schemes, investigate the origin of the respective artificial numerical diffusion and demonstrate how it could be diminished.<br/><br/>Description: 2000 Mathematics Subject Classification: 65M06, 65M12.New Coefficient Conditions for Functions Starlike with Respect to Symmetric Points
http://hdl.handle.net/10525/2701
Title: New Coefficient Conditions for Functions Starlike with Respect to Symmetric Points<br/><br/>Authors: Aghalary, R.; Ebadian, A.<br/><br/>Abstract: We consider some familiar subclasses of functions starlike with respect to symmetric points and obtain sufficient conditions for these classes in terms of their Taylor coefficient. This leads to obtain several new examples of these subclasses.<br/><br/>Description: 2000 Mathematics Subject Classification: Primary 30C45, secondary 30C80.Normal and Normally Outer Automorphisms of Free Metabelian Nilpotent Lie Algebras
http://hdl.handle.net/10525/2700
Title: Normal and Normally Outer Automorphisms of Free Metabelian Nilpotent Lie Algebras<br/><br/>Authors: Fιndιk, Şehmus<br/><br/>Abstract: Let Lm,c be the free m-generated metabelian nilpotent of class c Lie algebra over a field of characteristic 0. An automorphism φ of Lm,c is called normal if φ(I) = I for every ideal I of the algebra Lm,c. Such automorphisms form a normal subgroup N(Lm,c) of Aut (Lm,c) containing the group of inner automorphisms. We describe the group of normal automorphisms of Lm,c and the quotient group of Aut (Lm,c) modulo N(Lm,c).<br/><br/>Description: 2000 Mathematics Subject Classification: 17B01, 17B30, 17B40.More lr saturated L∞ spaces
http://hdl.handle.net/10525/2699
Title: More lr saturated L∞ spaces<br/><br/>Authors: Gasparis, I.; Papadiamantis, M. K.; Zisimopoulou, D. Z.<br/><br/>Abstract: Given r ∈ (1, ∞), we construct a new L∞ separable Banach space which is lr saturated.<br/><br/>Description: 2000 Mathematics Subject Classification: 05D10, 46B03.Totally Umbilical Pseudo-Slant Submanifolds of a Nearly Cosymplectic Manifold
http://hdl.handle.net/10525/2698
Title: Totally Umbilical Pseudo-Slant Submanifolds of a Nearly Cosymplectic Manifold<br/><br/>Authors: Khan, M. A.; Uddin, Siraj; Singh, Khushwant<br/><br/>Abstract: In the present note we study totally umbilical pseudo-slant submanifolds of a nearly cosymplectic manifold. We have obtained a classification theorem for totally umbilical pseudo-slant submanifolds of a nearly cosymplectic manifold.<br/><br/>Description: 2000 Mathematics Subject Classification: 53C40, 53B25.Fractional Trigonometric Korovkin Theory in Statistical Sense
http://hdl.handle.net/10525/2697
Title: Fractional Trigonometric Korovkin Theory in Statistical Sense<br/><br/>Authors: Anastassiou, George A.; Duman, Oktay<br/><br/>Abstract: In the present paper, we improve the classical trigonometric Korovkin theory by using the concept of statistical convergence from the summability theory and also by considering the fractional derivatives of functions. We also show that our new results are more applicable than the classical ones.<br/><br/>Description: 2000 Mathematics Subject Classification: 41A25, 41A36.Weitzenböck Derivations and Classical Invariant Theory: I. Poincaré Series
http://hdl.handle.net/10525/2696
Title: Weitzenböck Derivations and Classical Invariant Theory: I. Poincaré Series<br/><br/>Authors: Bedratyuk, Leonid<br/><br/>Abstract: By using classical invariant theory approach, formulas for computation of the Poincaré series of the kernel of linear locally nilpotent derivations are found.<br/><br/>Description: 2000 Mathematics Subject Classification: 13N15, 13A50, 16W25.