23 citations · 24 across the 2 of their papers we have counts for
5 papers
Kapranov rank vs. tropical rank
K. H. Kim, F. W. Roush
We show that determining Kapranov rank of tropical matrices is not only NP-hard over any infinite field but also if solving Diophantine equations over the rational numbers is undec…
Factorization of polynomials in one variable over the tropical semiring
Ki Hang Kim, Fred W. Roush
We show factorization of polynomials in one variable over the tropical semiring is in general NP-complete, either if all coefficients are finite, or if all are either 0 or infinity…
Decidability of the isomorphism problem for stationary AF-algebras and the associated ordered simple dimension groups
Ola Bratteli, Palle E. T. Jorgensen, Ki Hang Kim +1
The notion of isomorphism of stable AF-C*-algebras is considered in this paper in the case when the corresponding Bratteli diagram is stationary, i.e., is associated with a single…
The Williams Conjecture is false for irreducible subshifts
Ki Hang Kim, Fred W. Roush
We show the Williams Conjecture is false for irreducible shifts of finite type by examining relative sign-gyration numbers of conjugacies between shifts with no points of period on…
Non-stationarity of isomorphism between AF algebras defined by stationary Bratteli diagrams
Ola Bratteli, Palle E. T. Jorgensen, Ki Hang Kim +1
We first study situations where the stable AF-algebras defined by two square primitive nonsingular incidence matrices with nonnegative integer matrix elements are isomorphic even t…