The Knowledge Acquisition and Representation Language (KARL) combines a description of a knowledge-based system (kbs) at the conceptual level (a so-called model of expertise ) with a description at a formal and executable level. It is a specification language which allows the precise and unique description of a kbs independently from implementational details. In the paper, KARL is mainly discus...

We prove that certain Gibbs measures on subshifts of finite type are nonsingular and ergodic for certain countable equivalence relations, including the orbit relation of the adic transformation (the same as equality after a permutation of finitely many coordinates). The relations we consider are defined by cocycles taking values in groups, including some nonabelian ones. This generalizes (half ...

We review previous solutions of problem nr. 10769 posed by Christian Blatter A 1988 paper by C. D. Godsil and J. Zaks [1] states the following result, which is the solution of problem nr. 10769: “Let G be the graph with the points of the unit sphere in three dimensions as its vertices, and two vertices adjacent if and only if they are orthogonal as unit vectors (i.e., their spherical distance i...

*Alfred Wegener Institute for Polar and Marine Research, Telegrafenberg A43, D-14473 Potsdam, Germany {State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan Nanxincun 20, 100093 Beijing, China {Department of Plant Ecology and Natural Conservation, Institute of Biochemistry and Biology, University of Potsdam, Maulbeerallee 2, D-1...