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This paper mainly focuses on cones whose basis is a maximum h -scattered linear set. We start by investigating the intersection numbers of such cones with respect to the hyperplanes. Then we analyze two constructions of point sets with few intersection numbers with respect to the hyperplanes. In particular, the second one extends the construction of translation KM-arcs in projective spaces, having as part at infinity a cone with basis a maximum h -scattered linear set. As an instance of the second construction we obtain cylinders with a hyperoval as basis, which we call hypercylinders , for which we are able to provide a stability result. The main motivation for these problems is related to the connections with both Hamming and rank distance codes. Indeed, we are able to construct codes with few weights and to provide a stability result for the codes associated with hypercylinders. [ABSTRACT FROM AUTHOR]

The units of the chain ring R a = F p m [ u ] 〈 u a 〉 = F p m + u F p m + ⋯ + u a − 1 F p m are partitioned into a distinct types. It is shown that for any unit Λ of Type k , a unit λ of Type k ∗ can be constructed, such that the class of λ -constacyclic of length p s of Type k ∗ codes is one-to-one correspondent to the class of Λ -constacyclic codes of the same length of Type k via a ring isomorphism. The units of R a of the form Λ = Λ 0 + u Λ 1 + ⋯ + u a − 1 Λ a − 1 , where Λ 0 , Λ 1 , … , Λ a − 1 ∈ F p m , Λ 0 ≠ 0 , Λ 1 ≠ 0 , are considered in detail. The structure, duals, Hamming and homogeneous distances of Λ -constacyclic codes of length p s over R a are established. It is shown that self-dual Λ -constacyclic codes of length p s over R a exist if and only if a is even, and in such case, it is unique. Among other results, we discuss some conditions when a code is both α - and β -constacyclic over R a for different units α , β . [ABSTRACT FROM AUTHOR]