Egon Verharen

Meeting the Deadline: On the Formal Specification of Temporal Deontic Constraints

In this paper, we describe a temporal deontic logic that facilitates reasoning about obligations and deadlines. The logic is an extension of deontic dynamic logic, in which only immediate obligations can be specified. In our extension, we can also specify that an obligation starts at a certain time or event, that it must be done immediately, as soon as possible, before a deadline, or periodically. A practical application area are intelligent agents that must be able to reason about their agendas.

Implementation of a Cooperative Agent Architecture Based on the Language-Action Perspective

In this paper the architecture and implementation of Cooperative Information Agents (CIA) is described. Taking a language-action perspective to the design of CIAs allows for the specification of obligations and authorizations, and results in the separation of tasks (things the agent must do) and contracts (mutually agreed commitments to the course of communication). The architecture describes the functional components of a CIA: task manager (responsible for managing the agenda), contract manager (managing and negotiating contracts), communication manager (responsible for all external communication), and service execution manager (managing the execution of actions). The prototype agents show how a formal logical theory for communicating agents can be used as a sound basis for an actual implementation.

Dynamic business models as a basis for interoperable transaction design

Abstract Recent database research has given much attention to the specification of “flexible” transactions that can be used in interoperable systems. Starting from a quite different angle, Business Process Modelling has approached the area of communication modelling as well. The Language/Action perspective describes business processes by means of speech acts and commitments. These can be formalized by means of extended deontic logic. We argue that this logic provides the right concepts for specifying flexible transactions. To impose a modular structure on the specification, we make a distinction between the transaction level, the task level, and the contract. Extended deontic logic also offers the operators (communicative actions) by means of which one business process can be transformed into another. When these operators are provided to the subjects, business processes need no longer be seen as fixed once, but can become the subject of continuous negotiation and adaptation.

A Language/Action Perspective on cooperative information agents

Abstract The communication between different autonomous Information and Communication Systems requires a certain amount of intelligence of each system. One way of supporting this intelligence and autonomy is by means of Cooperative Information Agents (CIA). We show that basing the information contents of these agents on linguistic concepts and furthermore modelling the communications between the agents using the Language/Action Perspective provides for a natural and sound setting for these CIAs. In addition, we describe an agent architecture and agent language particularly suited for implementing communication systems.

Cooperative Information Agents and Communication

Research in Information Systems has switched its focus from data to communication. Communication between different autonomous ISs requires a certain amount of intelligence of each system. The system should be able to know which queries it can/may handle and also be able to negotiate about the information that it will give. In short, these systems evolve into what is called Cooperative Information Agents (CIA). We describe an architecture for these CIAs in which the relations of a CIA with other CIAs are handled on two levels. The messages themselves are handled by the communication manager. The communication manager can also negotiate a contract with other CIAs. The contracts (which may include communication or transaction protocols) between agents are handled by the contract manager of the CIA responsible for the contract. The messages between the agents are modeled using speech act theory which provides for a rich and flexible communication. In addition, we describe a lexicon in which the conceptual meaning of the terms of communication can be defined. Together, these levels provide an integrated and rich semantics for the communication between CIAs. These can be interorganizational, as in EDI applications, or intraorganizational, as in Workflow Management.

Interoperable Transactions in Business Models: A Structured Approach

Recent database research has given much attention to the specification of “flexible” transactions that can be used in interoperable systems. Starting from a quite different angle, Business Process Modelling has approached the area of communication modelling as well (the Language/Action perspective). The main goal of this paper is to provide some useful structuring mechanisms for interoperable transactions based on the Language/Action perspective. The paper thus tries to build a bridge between two rather separated worlds: the research on interoperable transactions on the one hand, and the research on business process models on the other. Extended deontic logic provides the material for this bridge. To better structure the specification, a distinction is proposed between the transaction level, the task level, and the contract.

Integrated Semantics for Information and Communication Systems

Traditionally, Data Semantics has dealt with the static and dynamic integrity rules of database systems. The database system was supposed to integrate different viewpoints on the Universe of Discourse of the organization. Nowadays, databases are often decentralized and its integrating function has been taken over by the network. Examples of new applications are EDI, Workflow Management and collaborative computing. To account for this evolution, we use the term Information and Communication System instead of Information System, and we argue that Data Semantics should move its focus to the semantics of communication (business proces models). We present a formal language based on Dynamic Logic in which the semantics of objects, actions, but also speech acts can be described. In addition, we describe a lexicon in which the conceptual meaning of the terms of communication can be defined. Together, these models provide an integrated semantics for Information and Communication systems.