We start with a combinatorial definition of I-sign types which are a generalization of the sign types indexed by the root system of type A_l (I is contained in N finite). Then we study the set D_p~I of I-sign types associated to the partial orders on I. We establish a 1-1 correspondence between D_p~([n]) and a certain set of polyhedral cones in a euclidean space by which we get a geometric distinction of the sign types in D_p~([n]) from the other [n]-sign types. We give a graph-theoretical criterion for an S_n-orbit O of D_p~([n]) to contain a dast and show that O contains at most one dast. Finally, we show the admirability of a poset associated to a dast.
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