Browsing School of Biological, Physical, Mathematics & Actuarial Sciences by Author "Okelo, Bernad N."

Now showing items 1-6 of 6

    • Certain properties of normaloid operators 

      Mogotu, P.O.; Kerongo, J.; Obogi, R. K.; Okelo, Bernad N. (JOOUST, 6/24/2015)
      In this paper we establish new conditions for contractivity of normaloid operators. We employ some results for contractivity due to Furuta, Nakomoto, Arandelovic and Dragomir. A particular generalization is also given.

    • Norm estimates for convexoid operators 

      Onyango, Cecil; Oleche, Paul; Okelo, Bernad N. (JOOUST, 6/24/2015)
      Hilbert space operators are important in formulation of principles of quantum mechanics and also in other fields of applied sciences. These operators include normal operators, hyponormal operators, normaloid operators, ...

    • Norms and numerical radii inequalities for (  ,  ) - normal transaloid operators 

      Nyaluke, Wesley K.; Okelo, Bernad N.; Ongati, Naftali O. (JOOUST, 6/24/2015)
      The studies on Hilbert spaces for the last decade has been of great interest to many mathematicians and researchers, especially on operator inequalities related to operator norms and numerical radii for a family of bounded ...

    • Norms of derivation associated with idempotents and unitary operators 

      Moses, Ouma O.; Ongati, Naftali O.; Okelo, Bernad N. (6/24/2015)
      The study of operators has continued to attract the attention of many researchers. Of special interest are the calculations of norms of these operators. Johnson Stampfli wrote a paper on the norms of derivation on algebra ...

    • On norm preserving conditions for local automorphisms of commutative banach algebras 

      Kangogo, Willy; Okelo, Bernad N.; Ongati, Naftali O. (JOOUST, 6/24/2015)
      The history of commutative algebra first appeared in 1890 by David Hilbert which was then followed by Banach spaces in 1924 since localization reduces many problems of geometric special case into commutative algebra problems ...

    • On numerical radius attainability for normal self-adjoint operators 

      Omaoro, Sabasi; Okelo, Bernad N. (JOOUST, 6/24/2015)
      The numerical range and numerical radius are very useful in studying linear operators acting on Hilbert spaces. The operators include normal, hyponormal, normaloid, transaloid, self-adjoint, subnormal, compact and unitary. ...