An approach to system specification defined by the Model-Driven Architecture (MDA) separates the specification of system functionality from the specification of the implementation of that functionality on a specific platform. To this end, the MDA proposes a framework for transforming a model into another model of the same system. The framework can also be used to transform a model into code for...

Novel trends in Web services technology challenge the assumptions made by current standards for process-based service composition. Most RESTful Web service APIs, which do not rely on the Web service description language (WSDL), cannot easily be composed using the BPEL language. In this paper we propose a lightweight BPEL extension to natively support the composition of RESTful Web services usin...

This paper introduces a formal metamodel for the specification of security policies for workflows in online service systems designed to be suitable for the modeling and analysis of complex business-related rules as well as traditional access control. A translation of the model into a colored Petri net is shown and an example of policy for an online banking system is described. By writing predic...

This paper presents a Petri net-based hierarchical architecture for multiple Unmanned Aerial Vehicle (UAV) simulations in order to facilitate rapid prototyping via visual modeling and analysis. Using high-level Colored Petri nets, we specify UAV control structure by a hierarchy of mission control net and task nets: the mission control net, built upon task nets, models the decision making proces...

Scientific Grid computing environments are increasingly adopting the Open Grid Services Architecture (OGSA), which is a service-oriented architecture for Grids. With the proliferation of OGSA, Grids effectively consist of a collection of Grid services, Web services with certain extensions providing additional support for state and life cycle management. Hence, the need arises for some means of ...