4 papers
Closure Semantics for Weak Modal Logics: Completeness and Representations
Yuki Nishimura
Weak modal logics can be obtained by restricting the axioms and inference rules governing the modal operator. At the extreme, one may consider the least modal logic, in which no sp…
Enumeration of Bases in Matroid with Exponentially Large Ground Set
Yuki Nishimura, Kazuya Haraguchi
When we deal with a matroid , we usually assume that it is implicitly given by means of the independence (IND) oracle. Time complexity of many existi…
Terminating Hybrid Tableaus for Ordered Models
Yuki Nishimura
Hybrid logic extends modal logic with special propositions called nominals, each of which is true at only one state in a model. This enables us to describe some properties of binar…
Complete and Terminating Tableau Calculus for Undirected Graph
Yuki Nishimura, Tsubasa Takagi
Hybrid logic is a modal logic with additional operators specifying nominals and is highly expressive. For example, there is no formula corresponding to the irreflexivity of Kripke…