  We introduce a temporal model for reasoning on disjunctive metric constraints
on intervals and time points in temporal contexts. This temporal model is
composed of a labeled temporal algebra and its reasoning algorithms. The
labeled temporal algebra defines labeled disjunctive metric point-based
constraints, where each disjunct in each input disjunctive constraint is
univocally associated to a label. Reasoning algorithms manage labeled
constraints, associated label lists, and sets of mutually inconsistent
disjuncts. These algorithms guarantee consistency and obtain a minimal network.
Additionally, constraints can be organized in a hierarchy of alternative
temporal contexts. Therefore, we can reason on context-dependent disjunctive
metric constraints on intervals and points. Moreover, the model is able to
represent non-binary constraints, such that logical dependencies on disjuncts
in constraints can be handled. The computational cost of reasoning algorithms
is exponential in accordance with the underlying problem complexity, although
some improvements are proposed.
