Content-Related Interval Queries on Object Histories

Abstract This paper initiates the investigation of "content-related" interval queries on object histories described by computation-tuple sequence schemes (CSS). Four primitive content-related interval queries, two variations for each of them, and two auxiliary interval queries are defined. The following problems are studied: (1) whether a query preserves CSS-describable sets, (2) whether a query preserves local-CSS describable sets, and (3) given a local-CSS describable set, whether a query returns a CSS-describable set.