Now showing items 3860-3879 of 5630

    • On Joint Essential Numerical Ranges 

      CYPRIAN, Omukhwaya Sakwa (Maseno University, 2013)
      The concept of numerical range on a Hilbert space was first introduced by O. Toeplitz in 1918 for matrices. This notion was independently ex tended by G. Lumer and F. Bauer in the sixties on finite dimensional Banach ...
    • On necessary Conditions for scalars 

      DO Adicka, W Mukuna, PO Oleche (Hikari Ltd, 2014)
      In this paper, we give a characterization of scalar operators. In particular we show that a densely defined closed linear operator H acting on a reflexive Banach space X is scalar if it is of (0, 1) type R and f (H)≤ f∞ ...
    • On Noncrossing and Plane Tree-Like Structures 

      Isaac Owino Okoth (Communications in Advanced Mathematical Sciences, 2021)
      Mathematical trees are connected graphs without cycles, loops and multiple edges. Various trees such as Cayley trees, plane trees, binary trees, d-ary trees, noncrossing trees among others have been studied extensively. ...
    • On norms of a derivation 

      BONYO, Job Otieno (Maseno university, 2010)
      The study of derivations still remains an area of interest to mathematicians today. Of special attention has been the study of norms of inner derivations. Most of the work in this area is based on Stampfli's result of ...
    • On norms of elementary operators 

      NYAARE , Benard Okelo (2009)
      The study of elementary operators has been of great interest to many mathematicians for the past two decades. Of special interest has been to determine the norms of these operators. The norm problem for elementary operators ...
    • On Numerical and Centre Values Range 

      John O Agure, Paul O Oleche (Int. Journal of Math, 2010)
      This paper follows [1] in the quantitative study of Numerical Ranges introduced by Stampfli [9]. In particular, we consider a family of mutually orthogonal projections and investigate how a numerical range can be related ...
    • On Numerical Range of Multiplication Operator 

      Odero Adhiambo Beatrice, JO Agure, FO Nyamwala (International Journal of Mathematical Analysis, 2019)
      Let H be an in nite dimensional complex Hilbert space and A;B 2 B(H) where B(H) is the C -algebra of all bounded linear operators on H. Let MAB : B(H) ! B(H) be a multiplication operator induced by A and B de- ned ...
    • On Regular Prime Graphs of Solvable Groups 

      Donnie Munyao Kasyoki, Paul Odhiambo Oleche (Hikari Ltd, 2016)
      Let G be a finite solvable group and∆(G) be the prime vertex graph on cd (G). We show that if∆(G) is noncomplete and regular, then G is the direct product of groups with disconnected graphs of 2 vertices.
    • On Schwarz norms 

      OKWANY, Isaac Odhiambo (Maseno University, 2015)
      Abstract Investigation of the properties of the numerical radius by Berger and Stampfli showed that indeed numerical radius norm is a Schwarz norm. Later on James P.Williams determined a family of distinct Schwarz norms ...
    • On shifted Fibonacci sequences and Their polynomials 

      ODUOL, Fidel Ochieng (Maseno University, 2020)
      Fibonacci sequences and their polynomials have been generalized mainly by two ways: by maintaining the recurrence relation and varying the initial conditions and by varying the recurrence relation and maintaining the ...
    • ON SINGULAR CAUCHY PROBLEM OF EULER-POISSON DARBOUX EQUATION 

      CC Wanjala Iyaya, WA Manyonge, Joseph Esekon (2012)
      We solve the singular Cauchy problem of Euler-Poisson-Darboux equation. The Riemann function, a solution corresponding to the adjoint equation is calculated and it enables us to evaluate any solution at a point by the ...
    • On some properties of generalized Fibonacci polynomials 

      Fidel Oduol (Open Journal of Discrete Applied Mathematics, 2020)
      Fibonacci polynomials have been generalized mainly by two ways: by maintaining the recurrence relation and varying the initial conditions and by varying the recurrence relation and maintaining the initial conditions. In ...
    • On The Algebraic Numerical Range of the Basic Elementary Operator and Norm of a Generalized Derivation 

      OBIERO, Beatrice Adhiambo (Maseno University, 2020)
      An elementary operator is a bounded linear map defined on the set of bounded linear operators acting on an infinite dimensional complex Hilbert space H. Various forms of elementary operators have been studied in the past ...
    • On the convexity of Stampfli's numerical range 

      JO Agure (Cambridge University Press, 1996-02)
      This paper investigates a certain type of numerical range introduced by Stampfli. In particular, we investigate the convexity of this set of elements of operators on Hilbert spaces and its relationship to the algebra ...
    • On the design and functionality of a solar chimney, Solar pressure-staged wind tunnel electric power Generating plant and an integrating sphere Calorimeter. I . I \ 

      OCHIENG, Reccab (Maseno University, 2009)
      The design and application of solar chimney and solar pressure-staged wind tunnel electric power generating plants involve the understanding of parameters which affect their operations and utilization. The size and ...
    • On the Essential Numerical Range 

      OWEGO, Dancun Okeso (Maseno University, 2013)
      The convexity. closure and compactness of the numerical range among other properties constitute a considerable literature in operator theory. The properties of the essential numerical range and how they are related to ...
    • On the Generalized Reid Inequality and the Numerical Radii 

      JO Bonyo, DO Adicka, JO Agure (Applied Mathematical Sciences, 2011)
      In this paper, we extend the generalized Reid inequality to include the numerical radii for the product of two Hilbert space operators. Mathematics Subject Classification: 47A12, 47A30, 47A63
    • On the maximal numerical range of elementary operators 

      Flora Mati Runji, John Ogonji Agure, Fredrick Oluoch Nyamwala (Academic Publications, Ltd., 2017-02)
      The notion of the numerical range has been generalized in different directions. One such direction, is the maximal numerical range introduced by Stampfli (1970) to derive an identity for the norm of a derivation on L(H). ...
    • On the Norm of a Generalized Derivation 

      Odero Adhiambo Beatrice, J. O. Agure,F. O. Nyamwala (HIKARI Ltd, 2019)
      Let H be an infinite dimensional complex Hilbert space and B(H) the algebra of all bounded linear operators on H. For two bounded operators A, B ∈ B(H), the map δAB : B(H) → B(H) is a generalized inner derivation operator ...
    • On the norm of elementary operator 

      Denis Njue Kingangi, John Ogoji Agure, Fredrick Oluoch Nyamwala (Scientific Research Publishing, 2014-07-07)
      The norm of an elementary operator has been studied by many mathematicians. Varied results have been established especially on the lower bound of this norm. Here, we attempt the same problem for finite dimensional operators.