Robert C. Kremer

A multi-resolution collaborative architecture for web-centric global manufacturing

We propose a recursive multi-resolution collaborative architecture (MRCA), based on multi-agent coordination mechanisms as a solid foundation for the development of web-centric cooperative applications in global manufacturing. The architecture consists of three layers: a low-level internetworking communication-support layer; a coordination layer ‐ managing inter-agent cooperation through intelligent conversation/communication mechanisms; and an agent layer consisting of five categories of agents: interface, collaboration, knowledge management, application and resource agents. From a functional perspective, two distinctive hierarchies shape the multi-dimensionality of this architecture: a vertical hierarchy of agents and a horizontal hierarchical communication‐coordination platform. The versatility of the proposed architecture (which supports practically any kind of collaborative application) and its recursive replication at all levels of resolution within the collaborative application are illustrated on a supply-chain example. ” 2000 Elsevier Science Inc. All rights reserved.

A Schema-Based Approach to Specifying Conversation Policies

This paper proposes a schema-based specification method for conversation policies in multi-agent systems. Conversation schemata are modeled through investigating conversational interactions among agents to exchange information. Information to be exchanged in a conversation interaction is specified through a set of “conversation topics”. Schemata are conversational patterns implementing this information exchanged and detailed by conversation acts. Colored Petri Nets are used as a specification and verification tool for conversation schemata at the design stage. Examples in agent-based manufacturing systems are used to illustrate the concepts and method proposed.

A collaborative agent-based infrastructure for Internet-enabled collaborative enterprises

The Internet has evolved very rapidly from an information space to a market space over the past few years. There is a tendency towards implementing real-world agent-based applications based on the Internet. This paper presents some results of our recent research work towards an infrastructure for Internet-enabled collaborative agent systems. The infrastructure and the related supporting services, components, prototypes and mechanisms are initially proposed and developed for Internet-enabled collaborative agent systems in all kinds of application areas, but they are primarily targeted for implementing Internet-enabled collaborative enterprises or supply chain management systems. The general collaborative agent system architecture with the basic communication and cooperation services, domain independent components, prototypes and mechanisms are described. The benefits of implementing Internet-enabled collaborative enterprises with the proposed infrastructure are discussed. A case study on multi-plant production planning is presented. Some important implementation issues are discussed.

A principled modular approach to construct flexible conversation protocols

Building conversation protocols has traditionally been an art more than a science, as their construction is often guided by designers’ intuition rather than by a principled approach. In this paper we present a model for building conversation protocols using inference principles that allow the computational specification and verification of message sequencing and turn-taking. This model, which is based on the negotiation of social commitments, results in highly flexible protocols that support agent heterogeneity while abiding by software engineering practices. We exemplify the specification of protocols using the contract net protocol, a common interaction protocol from the multiagent literature.

To Commit or Not to Commit: Modeling Agent Conversations for Action

Conversations are sequences of messages exchanged among interacting agents. For conversations to be meaningful, agents ought to follow commonly known specifications limiting the types of messages that can be exchanged at any point in the conversation. These specifications are usually implemented using conversation policies (which are rules of inference) or conversation protocols (which are predefined conversation templates). In this article we present a semantic model for specifying conversations using conversation policies. This model is based on the principles that the negotiation and uptake of shared social commitments entail the adoption of obligations to action, which indicate the actions that agents have agreed to perform. In the same way, obligations are retracted based on the negotiation to discharge their corresponding shared social commitments. Based on these principles, conversations are specified as interaction specifications that model the ideal sequencing of agent participations negotiating the execution of actions in a joint activity. These specifications not only specify the adoption and discharge of shared commitments and obligations during an activity, but also indicate the commitments and obligations that are required (as preconditions) or that outlive a joint activity (as postconditions). We model the Contract Net Protocol as an example of the specification of conversations in a joint activity.

Groupware concept mapping techniques

Concept maps have been used in education, policy studies and the philosophy of science to provide a visual representation of knowledge structures and argument forms. They provide a complementary alternative to natural language as a means of communicating knowledge. In many disciplines various forms of concept map are already used as formal knowledge representation systems, for example: semantic networks in artificial intelligence, bond graphs in mechanical and electrical engineering, Petri nets in communications, and category graphs in mathematics. This paper describes the design and application of a groupware concept mapping tool designed to support the knowledge processes of geographically dispersed communities.

A Pragmatic Approach to Build Conversation Protocols Using Social Commitments

We present a model to build conversation protocols aiming at the execution of actions. Our contention is that protocols can be explained as an orderly sequence of messages for adopting and discharging action-entailing social commitments. This model explicitly indicates the messages that are allowed (sequencing) and the agent that is expected to issue the next message (turn-taking) in all conversational states, thus defining state properties upon which the construction and verification of protocols can be based.

Bringing Coherence to Agent Conversations

In this paper, we present a social model for software agent conversations for action based on social commitments and their negotiation. We depart from the premises that conversations are cornerstone to support autonomous and heterogeneous agents, and that conversational coherence can be supported through public definitions of speech act and compositional semantics. We specify a unified social model for conversations in which speech act semantics is an emergent product of identity, conversational use, and potential consequences, and where conversational composition is guided by rules of conversational use and their application to the state of conversation instances. Lastly, we show the effectiveness of this novel approach by formally describing the evolution of a simple conversation for action.

Experiments with distance learning in software engineering graduate courses

This article reports on our experience to date with these two distance graduate courses in software engineering. We experimented with several technological tools to facilitate computer mediated communication: WebCT, electronic mail, a list server, and NetMeeting. We briefly discuss the methods used to evaluate the distance learning environments experienced by the graduate students, and make recommendations for future research and educational practice in distance learning environments.

Mapping visual to textual knowledge representation

In this paper, graphical representations for knowledge structures in the design method DESIRE for component-based design of knowledge and multi-agent systems are presented, together with a graphical editor based on the Constraint Graph environment. Moreover, a translator is described which translates these graphical representations to textual representations in DESIRE. The strength of the combined environment is a powerful-yet easy-to-use-framework to support the development of knowledge-based and multi-agent systems. Finally, a mapping is presented from DESIRE to Conceptual Graphs. This provides a unifying perspective on the knowledge representation format of DESIRE and allows the use of conceptual graph tools to specify and maintain the knowledge representation part of a DESIRE specification.