Frances M. T. Brazier

DESIRE: Modelling Multi-Agent Systems in a Compositional Formal Framework

This paper discusses an example of the application of a high-level modelling framework which supports both the specification and implementation of a systems conceptual design. This framework, DESIRE (framework for DEsign and Specification of Interacting REasoning components), explicitly models the knowledge, interaction, and coordination of complex tasks and reasoning capabilities in agent systems. For the application domain addressed in this paper, an operational multi-agent system which manages an electricity transportation network for a Spanish electricity utility, a comprehensible specification is presented.

Principles of component-based design of intelligent agents

Compositional multi-agent system design is a methodological perspective on multi-agent system design based on the software engineering principles process and knowledge abstraction, compositionality, reuse, specification and verification. This paper addresses these principles from a generic perspective in the context of the compositional development method DESIRE. An overview is given of reusable generic models (design patterns) for different types of agents, problem solving methods and tasks, and reasoning patterns. Examples of supporting tools are described.

Supporting internet-scale multi-agent systems

The Internet provides a large-scale environment for (intelligent) software agents. Agents are autonomous (mobile) processes, capable of communication with other agents, interaction with the world, and adaptation to changes in their environment. Current approaches to support agents are not geared for large-scale settings. The near future holds thousands of agents, hosts, messages, and migratory movements of agents. These large-scale aspects require a new approach to facilitate the development of agent applications and support. AgentScape is a scalable agent-based distributed system, described in this paper, that aims at tackling these aspects.

Scalable middleware environment for agent-based internet applications

The AgentScape middleware is designed to support deployment of agent-based applications on Internet-scale distributed systems. With the design of AgentScape, three dimensions of scalability are considered: size of distributed system, geographical distance between resources, and number of administrative domains. This paper reports on the AgentScape design requirements and decisions, its architecture, and its components.

A method for decentralized clustering in large multi-agent systems

This paper examines a method of clustering within a fully decentralized multi-agent system. Our goal is to group agents with similar objectives or data, as is done in traditional clustering. However, we add the additional constraint that agents must remain in place on a network, instead of first being collected into a centralized database. To do this we connect agents in a random network and have them search in a peer-to-peer fashion for other similar agents. We thus aim to tackle the basic clustering problem on an Internet scale and create a method by which agents themselves can be grouped, forming coalitions. In order to investigate the feasibility of a decentralized approach, this paper presents a number of simulation experiments involving agents representing two-dimensional points. A comparison between our methods clustering ability and that of the k-means clustering algorithm is presented. Generated data sets containing 2,500 to 160,000 points (agents) grouped in 25 to 1,600 clusters are examined. Results show that our decentralized agent method produces a better clustering than the centralized k-means algorithm, quickly placing 95% to 99% of points correctly. The the time required to find a clustering depends on the quality of solution required; a fairly good solution is quickly converged on, and then slowly improved. Overall, our experiments indicate that the time to find a particular quality of solution increases less than linearly with the number of agents.

Agents and Service-Oriented Computing for Autonomic Computing: A Research Agenda

Autonomic computing is the solution proposed to cope with the complexity of todays computing environments. Self-management, an important element of autonomic computing, is also characteristic of single and multiagent systems, as well as systems based on service-oriented architectures. Combining these technologies can be profitable for all - in particular, for the development of autonomic computing systems.

ON FORMAL SPECIFICATION OF DESIGN TASKS

In the development of a design system, a formal specification can play an important role providing a precise description of both the static and the dynamic aspects of the system. Static aspects not only include domain knowledge about properties of design objects and relations between these properties, but also domain knowledge about requirements of design objects and relations between these requirements. Dynamic aspects include strategic knowledge about steps undertaken in the design process. In this paper, a logical framework for design tasks is presented which incorporates the notion of a meta-level architecture to explicitly represent declarative knowledge on the dynamics of reasoning processes. Based on this logical framework a generic task model of design is presented, describing the essential structure of the design task, in which the dynamic modification of design object descriptions and requirements is explicitly defined.

A multi-agent system performing one-to-many negotiation for load balancing of electricity use

Abstract Emerging technologies allowing two-way communication between utility companies and their customers are changing the rules of the energy market. Deregulation makes it even more demanding for utility companies to create new business processes for the mutual benefit of the companies and their customers. Dynamic load management of the power grid is essential to make better and more cost-effective use of electricity production capabilities, and to increase customer satisfaction. In this paper, methods from agent technology and knowledge technology have been used to analyse, design, and implement a component-based multi-agent system capable of negotiation for load management. The proof-of-concept prototype system NALM (negotiating agents for load management) developed shows how under certain assumptions peaks in power load can be reduced effectively based on a negotiation process.

Composing Web Services Using an Agent Factory

Web service composition can provide a value-chain between customers and suppliers. The increasing number of services, and thus possible combinations, demands the development of dynamic and automatic techniques for their composition. Current commercial solutions are limited and are primarily static and manual. Automation requires reasoning about (semantic descriptions of) the services. This paper describes our initial work which brings together agents, Web service and semantic Web technology. Our knowledge-based software engineering approach to the design of agents, known as the Agent Factory, is applied to the composition of Web services. Using semantic descriptions of Web services written in DAML-S, the design process in our Agent Factory derives a Web service configuration. This paper also includes some observations regarding our experiences with DAML-S, UDDI and WSDL for this purpose.

Formalization of a Cooperation Model Based on Joint Intentions

A cooperation model based on joint intentions introduced by Jennings is formalised within the modelling framework DESIRE for compositional multi-agent systems. By formalising the model in the DESIRE framework operationalisation and reusability of the model are obtained, as DESIRE specifications are executable and easily reusable.