For an arbitrary triadic relation '''L''' ⊂ '''O''' × '''S''' × '''I''', whether it is a sign relation or not, there are six ''[[binary relation|dyadic relation]]s'' that can be obtained by ''[[projection (set theory)|projecting]]'' '''L''' on one of the planes of the '''OSI'''-space '''O''' × '''S''' × '''I'''. The six dyadic projections of a triadic relation '''L''' are defined and notated as follows:
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For an arbitrary triadic relation '''L''' ⊆ '''O''' × '''S''' × '''I''', whether it is a sign relation or not, there are six ''[[binary relation|dyadic relation]]s'' that can be obtained by ''[[projection (set theory)|projecting]]'' '''L''' on one of the planes of the '''OSI'''-space '''O''' × '''S''' × '''I'''. The six dyadic projections of a triadic relation '''L''' are defined and notated as follows: