Dialog

Miryana Hristova
Commutational Properties of Powers of Operators of Mixed Type Increasing the Powers
JEL: C65, C69

Keywords: commutant of linear operator, minimal commutativity

Summary: The operators were considered in [11] with non-negative integers. Here they are considered with parameters in the space of the polynomials with complex coefficients or in the space of functions analytic in neighbourhoods of the origin. Power series description of the commutant of powers of is given and then the question about the minimal commutativity of H (in the sense of Raichinov [13]) is discussed.
Maya Lambovska
A Model for Performance Evaluation of Responsibility Centers in the Organization
JEL: M19, C65

Keywords: Evaluation, responsibility centers, budgetary control, fuzzy numbers, fuzzy logic

Summary: This article presents a model for performance evaluation of responsibility centers in the budgetary management process of the organization. The model is based on sophisticated instruments, including classical management tools and contemporary mathematical tools of theory of fuzzy logic and fuzzy subsets. The model is presented conceptually and methodologically (by algorithm for implementation). One possible application of the model is illustrated in four versions by an example for a cost center operating in uncertain and stable / dynamic environment.