Electronic markets, dispute resolution and negotiation protocols are three types of application domains that can be viewed as open agent societies. Key characteristics of such societies are agent heterogeneity, conflicting individual goals and unpredictable behavior. Members of such societies may fail to, or even choose not to, conform to the norms governing their interactions. It has been argued that systems of this type should have a formal, declarative, verifiable, and meaningful semantics. We present a theoretical and computational framework being developed for the executable specification of open agent societies. We adopt an external perspective and view societies as instances of normative systems. In this article, we demonstrate how the framework can be applied to specifying and executing a contract-net protocol. The specification is formalized in two action languages, the C + language and the Event Calculus, and executed using respective software implementations, the Causal Calculator and the Society Visualizer. We evaluate our executable specification in the light of the presented case study, discussing the strengths and weaknesses of the employed action languages for the specification of open agent societies.

E-markets and negotiation protocols are two types of application domains that can be viewed as open computational societies. Key characteristics of such societies are agent heterogeneity, conflicting individual goals and limited trust. The risk that members of such societies will not conform to specifications imposes the need for a framework that will facilitate the designers to determine to what extent it is desirable to deploy their agents in such societies. We address this need by presenting a formal framework for specifying, animating, and ultimately reasoning about and verifying the properties of open computational systems. We view computational systems from an external perspective, aiming to account for the institutional and social aspects of these systems. We identify the key concepts and illustrate how they are used by formalising an example employing the contract net protocol. The framework and associated logical inferences have been implemented as a software platform that provides automated animation of the global states of an open system (society) during its execution. Simulations have demonstrated that the implementation of the framework establishes a foundation for a rich, formal representation of open computational societies.

We present a system for online monitoring of maritime activity over streaming positions from numerous vessels sailing at sea. It employs an online tracking module for detecting important changes in the evolving trajectory of each vessel across time, and thus can incrementally retain concise, yet reliable summaries of its recent movement. In addition, thanks to its complex event recognition module, this system can also offer instant notification to marine authorities regarding emergency situations, such as risk of collisions, suspicious moves in protected zones, or package picking at open sea. Not only did our extensive tests validate the performance, efficiency, and robustness of the system against scalable volumes of real-world and synthetically enlarged datasets, but its deployment against online feeds from vessels has also confirmed its capabilities for effective, real-time maritime surveillance.