  When implementing the DSmT, a difficulty may arise from the possible huge
dimension of hyperpower sets, which are indeed free structures. However, it is
possible to reduce the dimension of these structures by involving logical
constraints. In this chapter, the logical constraints will be related to a
predefined order over the logical propositions. The use of such orders and
their resulting logical constraints will ensure a great reduction of the model
complexity. Such results will be applied to the definition of continuous DSm
models. In particular, a simplified description of the continuous impreciseness
is considered, based on impreciseness intervals of the sensors. From this
viewpoint, it is possible to manage the contradictions between continuous
sensors in a DSmT manner, while the complexity of the model stays handlable.
