On differences of self-adjoint semigroups

Generalized Adjoint Semigroups of a Ring

In this paper, we introduce generalized adjoint semigroups (GA-semigroups) of a ring R. We construct generalized adjoint semigroups on a ring R by means of bitranslations of R. It is shown that GA-semigroups of a π-regular ring are π-regular. As an application we deduce that in any ring, idempotents can be lifted modulo π-regular ideals. GA-semigroups containing idempotents are described in ter...

Adjoint and self - adjoint differential operators on graphs ∗

A differential operator on a directed graph with weighted edges is characterized as a system of ordinary differential operators. A class of local operators is introduced to clarify which operators should be considered as defined on the graph. When the edge lengths have a positive lower bound, all local self-adjoint extensions of the minimal symmetric operator may be classified by boundary condi...

On Families of Self Adjoint Operators

On the computation of spectra and pseudospectra of self-adjoint and non-self-adjoint Schrödinger operators

We consider the long standing open question on whether one can actually compute spectra and pseudospectra of arbitrary (possibly non-self-adjoint) Schrödinger operators.We conclude that the answer is affirmative for “almost all” such operators, meaning that the operators must satisfy rather weak conditions such as the spectrum cannot be empty nor the whole plane. We include algorithms for the g...

an investigation of the impact of self monitoring on langauge teachers motivational practice and its effect on learners motivation

the central purpose of this study was to conduct a case study about the role of self monitoring in teacher’s use of motivational strategies. furthermore it focused on how these strategies affected students’ motivational behavior. although many studies have been done to investigate teachers’ motivational strategies use (cheng & d?rnyei, 2007; d?rnyei & csizer, 1998; green, 2001, guilloteaux & d?...