University of Porto Shell

UPShell (University of Porto Shell) is a tool for generating multi-agent systems suitable for industrial applications.
UPShell may be used to generate specific Intelligent Systems, but its main purpose is to transform a set of these generated Intelligent Systems together with other knowledge based systems, into a community of cooperative agents. The Shell guides the user through menus to allow him to install the community of agents. The user only has to select the agents (from the available ones) and the machines on which each agent should run. When lauching the agents, UPShell builds on the top of each knowledge based system another module - the Cooperation Layer - which controls the activity of the knowledge based system and the cooperation with the rest of the community. Each knowledge based system together with its cooperation layer constitutes an agent of the community. All the agents of the community run "simultaneously", as two separated UNIX processes per agent, one for the knowledge based system and another for the cooperation layer. Each cooperation layer of an agent can communicate to any other cooperation layer, and also to its knowledge based system through a mechanism of message passing implemented using UDP UNIX sockets. When the agents are launched in the respective machines, default values for sockets are provided, and communications are tested, so that the user does not need to care about them. The knowledge based systems may be either built-in by UPShell or pre-existing ones, in which case, it is necessary to build up their self models interactively with UPShell.

When UPShell is launching the agents, based on the self models of each knowledge based system, it creates for each agent a model of all its acquaintances (only about systems and items in which it is interested).
The cooperation layer of each agent uses an internal blackboard to access all information needed to make appropriate decisions about internal activity (problem solving) as well as external activity (cooperation and communication). Here, the blackboard paradigm is not used as a communication and cooperation framework among different agents, but only for internal purposes.

This work has been developed in the framework of the Esprit II Project (P-2256) ARCHON - ARchitecture for Cooperative Heterogeneous ON-line Systems.

Mail: Faculdade de Engenharia, Rua dos Bragas, 4099 PORTO codex, PORTUGAL
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Last Updated: 24/02/96