Catálogo de publicaciones - libros

One of the main challenges for the successful application of agent-based systems in mobile and embedded devices is enabling application developers to reconcile the needs of the user to the capabilities and limitations of agents in the context of environments with changing and often limited resources. In this paper we present an attempt to move towards a solution through a framework for defining and reasoning about agents in a manner that is modular and reconfigurable at run-time. Departing from the theoretical basis afforded by the SMART framework, we extend it to enable the definition of fully re-configurable component-based agent architectures. The guiding principle of this approach is an architecturally-neutral model that supports a separation between the description, behaviour and structure of an agent.

The agent-oriented approach has been successfully applied to the solution of complex problems in dynamic open environments. However, to extend its use to mainstream computing and industrial environments, appropriate software tools are needed. Arguably, software methodologies form the most important type of these software tools. Although several agent-oriented methodologies have been proposed to date, none of them is mature enough to be used in industrial environments. In particular, they typically don’t include catalogues of patterns that are necessary for addressing issues of reuse and speed of development. Two possible approaches to overcome such weaknesses in current agent-oriented methodologies are: to propose new methodologies, or to enhance existing ones. In this paper, the latter approach is taken, offering an enhancement of the Gaia methodology to include a catalogue, specifically concerned with a set of organisational patterns. Each of these patterns contains the description of a structure that can be used to model the organisation of agents in specific applications. The use of these patterns helps to reduce development time and promotes reusability of design models.

In the paper we study the dynamics of roles played by agents in multiagent systems. We capture role dynamics in terms of four operations performed by agents: ‘enactment’, ‘deactment’, ‘activate’, and ‘deactivate’. The use of these operations is motivated, in particular for open systems. A formal semantics for these operations is provided. This formalization is aimed at serving as a basis for implementation of role dynamics in an agent programming language such as 3APL.

Agents show considerable promise as a new paradigm for software development. However for wider adoption and deployment of agent technology, powerful design and development tools are needed. Such tools should empower software developers to cater agent solutions more efficiently and at a lower cost for their customers with rapidly changing requirements and differing application specifications.

In this paper, an agent orchestration platform that allows the developers to design a complete agent-based scenario through graphical user interfaces is presented. The scenario produced by the platform is a rule based system in contrast to the existing systems where agents are coded through a programming language. In this way, the platform provides a higher level of abstraction to agent development making it easier to adapt to rapidly changing user requirements or differing software specifications. The system is highly transportable and interoperable.

The platform helps to design a multi-agent system either from scratch, or by adapting existing distributed systems to multi agent systems. It contains tools that handle the agent system design both at the macro level, that is, defining the interaction between agents and at the micro level which deals with internal design of agents.

Agent behaviour is modeled as a workflow of basic agent behaviour building blocks (such as receiving a message, invoking an application, making a decision or sending a message) by considering the data and control dependencies among them, and a graphical user interface is provided to construct agent behaviours. The platform allows agent templates to be constructed from previously defined behaviours. Finally through a Scenario Design Tool, a multi-agent system is designed by specifying associations among agents. The scenario is stored in a knowledge base by using the Agent Behaviour Representation Language (ABRL) which is developed for this purpose. Finally to be able to demonstrate the execution of the system on a concrete agent platform, we mapped the ABRL rules to JESS and executed the system on JADE.

Multiagent organizations provide a powerful way for developing multiagent systems. This paper presents a methodology for designing organizations based on formal specification of requirements for organizational behavior and requirements refinement related to organizational structure. The approach allows parts of an organization to be designed in parallel and later be put together to satisfy the broader requirements of the organization. Using this approach, organizational building blocks can be formally specified, appropriately indexed and stored in an organization design library. The library structure is supported by software tools and allows designers with varying levels of expertise to benefit from it by accommodating queries at different abstraction levels and by providing support for query reformulation.