In this paper we discuss the exploration of a model checker’s counterexample trace using model-based debugging techniques. We show that a diagnosis model obtained from a single counterexample run in an event-driven simulation is not appropriate for localizing a failures real cause in general. Notably, modeling VHDL’s event and process semantics as originally defined hampers the integration of t...

In this paper we tackle the problem of designing and implementing a framework for programming service coordination policies. In particular, we illustrate the design and the prototype implementation of Java Signal Core Layer (JSCL), a coordination middleware for services based on the event notification paradigm. We formally motivate the design choices of the JSCL middleware by exploiting a varia...

Traditional visual servoing systems have been widely studied in the last years. These systems control the position of the camera attached to the robot end-effector guiding it from any position to the desired one. These controllers can be improved by using the event-based control paradigm. The system proposed in this paper is based on the idea of activating the visual controller only when someth...

The lack of formal semantics of traditional approaches to business process modeling negatively affects the integration and sharing of models. The approaches that provide a semantics often do not discuss the ontological foundation of the assumed primitives hindering the intelligibility of the models. We propose an ontological founded modeling framework in which synchronic properties and relation...

As computing systems get larger in capability a good thing they also get larger in ways less desirable: cost, volume, power requirements and so on. Further, as the datastructures necessary to support large computations grow physically, the proportion of wallclock time spent communicating increases dramatically at the expense of the time spent calculating. This state of affairs is currently unac...

Implementation architectures of today are based on the modularisation of software into objects, components, web services, (intelligent) agents, ... with communication and coordination between components being based on peer-topeer communication (a client-component requests a service from a servercomponent). Because this binary and uni-directional form of communication implies substantial restric...

A new domain-independent knowledge-based inference structure is presented, specific to the task of abstracting higher-level concepts from time-stamped data. The framework includes a model of time, parameters, events, and contexts. A formal specification of a domainÕs temporal-abstraction knowledge supports acquisition, maintenance, reuse, and sharing of that knowledge. The knowledge-based tempo...

This paper presents RAMSES, a framework for easily specifying agent-based discrete event models entailing both environment and agent entities. RAMSES offers parallel execution capabilities based on speculative event processing and an innovative software reversibility technique that copes with state restore in case the run slides along a nonconsistent speculative path. Reversibility in RAMSES re...

estimation of parameters of a hydrologic model is undertaken using a procedure called “calibration” in order to obtain predictions as close as possible to observed values. this study aimed to use the particle swarm optimization (pso) algorithm for automatic calibration of the hec-hms hydrologic model, which includes a library of different event-based models for simulating the rainfall-runoff pr...