Abstract :
The key notion for modelling calendar systems as well as many periodic events, for example the seasons, is the notion of a partitioning of the real numbers. A partitioning of R splits the time axis into a finite or infinite sequence of intervals. Basic time units like seconds, minutes, hours, days, weeks, months, years etc. can all be represented by finite partitionings of R. There are a lot of other temporal notions which can be modelled as partitions either: the seasons, the ecclesiastical calendars, financial years, semesters at universities, the sequence of sunrises and sunsets, the sequence of the tides, the sequence of school holidays etc. In this paper, a formalization of periodic temporal notions by means of partitionings R is presented.
Keywords :
knowledge representation; sequences; temporal reasoning; time management; calendar systems; ecclesiastical calendars; finite partitionings; finite sequence; infinite sequence; labelled partitionings; periodic events; periodic temporal notions; school holidays sequence; seasons; sunrises sequence; sunsets sequence; tides sequence; Algebra; Books; Calendars; Educational institutions; Partitioning algorithms; Prototypes; Specification languages; System testing; Tides;