The canonical module of a Cox ring

In this paper, we shall describe the graded canonical module of a Noetherian multi-section ring of a normal projective variety. In particular, in the case of the Cox ring, we prove that the graded canonical module is a graded free module of rank one with the shift of degree $K_X$. We shall give two kinds of proofs. The first one utilizes the equivariant twisted inverse functor developed by the first author. The second proof is down-to-earth, that avoids the twisted inverse functor.Comment: 19 pages, corrected minor errors and updated the reference

Strategy-Proof and Anonymous Rule in Queueing Problems: A Relationship between Equity and Efficiency

In this paper, we consider a relationship between equity and efficiency in queueing problems. We show that under strategy-proofness, anonymity in welfare implies queue-efficiency. Furthermore, we also give a characterization of the equally distributed pairwise pivotal rule, as the only rule that satisfies strategy-proofness, anonymity in welfare and budget-balance.Queueing Problems, Strategy-Proofness, Anonymity in welfare, Efficiency