Recently, Abdulla and Čerāns (1998) outlined an extensive and involved proof of the decidability of simulation preorder for one-counter nets. In this note, we present a short, complete proof based on simple colourings of the plane.1 1This paper was written during a visit by the first author to Uppsala University supported by a grant from the STINT Fellowship Programme. He is also partially supp...

We consider the problem of simulation preorder/equivalence between in nitestate processes and nite-state ones. We prove that simulation preorder (in both directions) and simulation equivalence are intractable between all major classes of in nite-state systems and nite-state ones. This result is obtained by showing that the problem whether a BPA (or BPP) process simulates a nite-state one is PSP...

Variants of the must testing approach have been successfully applied in Service Oriented Computing for analysing the compliance between (contracts exposed by) clients and servers or, more generally, between two peers. It has however been argued that multiparty scenarios call for more permissive notions of compliance because partners usually do not have full coordination capabilities. We propose...

We consider the problem of simulation preorder/equivalence between infinite-state processes and finite-state ones. We prove that simulation preorder (in both directions) and simulation equivalence are intractable between all major classes of infinite-state systems and finite-state ones. This result is obtained by showing that the problem whether a BPA (or BPP) process simulates a finitestate on...

Recently, Aceto, Fokkink & Ingólfsdóttir proposed an algorithm to turn any sound and ground-complete axiomatisation of any preorder listed in the linear time – branching time spectrum at least as coarse as the ready simulation preorder, into a sound and ground-complete axiomatisation of the corresponding equivalence—its kernel. Moreover, if the former axiomatisation is ω-complete, so is the lat...

This paper considers a weak simulation preorder for Markov chains that allows for stuttering. Despite the second-order quantification in its definition, we present a polynomial-time algorithm to compute the weak simulation preorder of a finite Markov chain.  2003 Elsevier B.V. All rights reserved.

We consider the problem of simulation preorder/equivalence between innnite-state processes and nite-state ones. We prove that simulation preorder (in both directions) and simulation equivalence are intractable between all major classes of innnite-state systems and nite-state ones. This result is obtained by showing that the problem whether a BPA (or BPP) process simulates a nite-state one is PS...

We characterize the existence of a nonnegative, sublinear and continuous order-preserving function for a not necessarily complete preorder on a real convex cone in an arbitrary topological real vector space. As a corollary of the main result, we present necessary and sufficient conditions for the existence of such an order-preserving function for a complete preorder.