the class of all classes. we consider a class as a unary relation, true for all its instance
a minute-in-time is an integer in the interval 0-5
(apply f (arg1....argn)) is the same as(f arg1...argn)
the class of defined relations. we assume fixed arit
a predicate to test whether a number is greater than anothe
a calendar date is a time point in which month, day and year havebeen specified but hour, minute and second have not
the same as holds, but takes only one argument, a sentence whose truthvalue is to be checked
suo: physical quantities are distinguished from numbers by thefact that the former are associated with a dimension of measurement.
an interval is defined by two time points or a duration.classes of intervals, e.g., a day, can be defined by specifying onlya duration. a time interval has no gaps
a tuple, say <t1 t2 t3> is an element of function f iff(= (apply f ti t2) t3) is satisfied
a year-in-time must be an integer and integer can be a year-in-tim
returns the last element of a list. if ?list is emptythen :nothing is returned
a second-in-time is a real number greater or equal to 0, less than 6
a time position is either a time interval or a time point.any time position is relative to a time zone
this is the top-level concept in the akt reference ontolog
a day-in-time is an integer in the interval 1-3
this is the basic set constructor to create a set by enumerating its elements.for instance, (setof 1 2) denotes the set {1 2}.we represent such a set as a list whose first item is :set
the duration between two time points.no operational definition is given here, only a spec
a month-in-time is an integer in the interval 1-1
a hour-in-time is an integer in the interval 0-2
like in cyc, this is something which has a temporal extent