1,681 research outputs found
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)
Working Notes from the 1992 AAAI Spring Symposium on Practical Approaches to Scheduling and Planning
The symposium presented issues involved in the development of scheduling systems that can deal with resource and time limitations. To qualify, a system must be implemented and tested to some degree on non-trivial problems (ideally, on real-world problems). However, a system need not be fully deployed to qualify. Systems that schedule actions in terms of metric time constraints typically represent and reason about an external numeric clock or calendar and can be contrasted with those systems that represent time purely symbolically. The following topics are discussed: integrating planning and scheduling; integrating symbolic goals and numerical utilities; managing uncertainty; incremental rescheduling; managing limited computation time; anytime scheduling and planning algorithms, systems; dependency analysis and schedule reuse; management of schedule and plan execution; and incorporation of discrete event techniques
Context-based modelling of information demand: approaches from information logistics and decision support
Readily available information is a crucial basis for making decisions, solving problems, or performing knowledge intensive work. Providing such information meeting the needs of a user has to be based on an accurate, purpose-oriented and up-to-date representation of the demand in question. The paper is devoted to a study of different context-based models of user demand. The selected approaches from the fields of information logistics and decision support are based on enterprise models and objectoriented constraint networks (OOCN). Combining these approaches will allow for an orchestrated use of enterprise models and OOCN for decision support. Discussion and integration of these approaches is illustrated using an example enterprise model, a related information demand context and a corresponding decision support context
Automated Service Composition Using AI Planning and Beyond
Automated Service Composition is one of the ``grand challenges'' in the area of Service-Oriented Computing. Mike Papazoglou was not only one of the first researchers who identified the importance of the problem, but was also one of the first proposers of formulating it as an AI planning problem. Unfortunately, classical planning algorithms were not sufficient and a number of extensions were needed, e.g., to support extended (rich) goal languages to capture the user intentions, to plan under uncertainty caused by the non-deterministic nature of services; issues that where formulated (and, partially addressed) by Mike, being one of his key contributions to the service community
- …