Web Services: A Process Algebra Approach

It is now well-admitted that formal methods are helpful for many issues raised in the Web service area. In this paper we present a framework for the design and verification of WSs using process algebras and their tools. We define a two-way mapping between abstract specifications written using these calculi and executable Web services written in BPEL4WS. Several choices are available: design and correct errors in BPEL4WS, using process algebra verification tools, or design and correct in process algebra and automatically obtaining the corresponding BPEL4WS code. The approaches can be combined. Process algebra are not useful only for temporal logic verification: we remark the use of simulation/bisimulation both for verification and for the hierarchical refinement design method. It is worth noting that our approach allows the use of any process algebra depending on the needs of the user at different levels (expressiveness, existence of reasoning tools, user expertise)

Additive Focus Adverbs in Canonical Word Orders. A Corpus-based Study of It. anche, Fr. aussi and E. also in Written News

The goal of this paper is to offer a cross-linguistic analysis of the most commonly occurring additive focus adverbs used in Italian, French and English – namely anche, aussi and also – on the basis of a corpus of written texts. The corpus used in this paper consists of comparable online news in Italian, French and English amounting to approximately 750000 words. In line with previous findings, our results show that there are important quantitative and qualitative differences between It. anche, Fr. aussi and E. also. These items differ not only in their overall frequency of use but also in the specific syntactic configurations in which they occur when they associate with the Subject of a canonical sentence. These differences are partly enhanced by the fact that this paper concentrates on a non-prototypical configuration, i. e. on the cases in which the canonical Subject coincides with a new entity while the Predicate is maintained