Socionic Multi-Agent Systems Based on Reflexive Petri Nets and Theories of Social Self-Organisation

This contribution summarises the core results of the transdisciplinary ASKO project, part of the German DFG's programme Sozionik, which combines sociologists' and computer scientists' skills in order to create improved theories and models of artificial societies. Our research group has (a) formulated a social theory, which is able to explain fundamental mechanisms of self-organisation in both natural and artificial societies, (b) modelled this in a mathematical way using a visual formalism, and (c) developed a novel multi-agent system architecture which is conceptually coherent, recursively structured (hence non-eclectic) and based on our social theory. The article presents an outline of both a sociological middle-range theory of social self-organisation in educational institutions, its formal, Petri net based model, including a simulation of one of its main mechanisms, and the multi-agent system architecture SONAR. It describes how the theory was created by a re-analysis of some grand social theories, by grounding it empirically, and finally how the theory was evaluated by modelling its concepts and statements.Multi-Agents Systems, Petri Nets, Self-Organisation, Social Theories

Workshop on Modelling of Objects, Components, and Agents, Aarhus, Denmark, August 27-28, 2001

This booklet contains the proceedings of the workshop Modelling of Objects, Components, and Agents (MOCA'01), August 27-28, 2001. The workshop is organised by the CPN group at the Department of Computer Science, University of Aarhus, Denmark and the "Theoretical Foundations of Computer Science" Group at the University of Hamburg, Germany. The papers are also available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop01

Representing Conversations for Scalable Overhearing

Open distributed multi-agent systems are gaining interest in the academic community and in industry. In such open settings, agents are often coordinated using standardized agent conversation protocols. The representation of such protocols (for analysis, validation, monitoring, etc) is an important aspect of multi-agent applications. Recently, Petri nets have been shown to be an interesting approach to such representation, and radically different approaches using Petri nets have been proposed. However, their relative strengths and weaknesses have not been examined. Moreover, their scalability and suitability for different tasks have not been addressed. This paper addresses both these challenges. First, we analyze existing Petri net representations in terms of their scalability and appropriateness for overhearing, an important task in monitoring open multi-agent systems. Then, building on the insights gained, we introduce a novel representation using Colored Petri nets that explicitly represent legal joint conversation states and messages. This representation approach offers significant improvements in scalability and is particularly suitable for overhearing. Furthermore, we show that this new representation offers a comprehensive coverage of all conversation features of FIPA conversation standards. We also present a procedure for transforming AUML conversation protocol diagrams (a standard human-readable representation), to our Colored Petri net representation

Coloured Petri Nets - a Pragmatic Formal Method for Designing and Analysing Distributed Systems

The thesis consists of six individual papers, where the present paper contains the mandatory overview, while the remaining five papers are found separately from the overview. The five papers can roughly be divided into three areas of research, namely case studies, education, and extensions to the CPN method.The primary purpose of the PhD thesis is to study the pragmatics, practical aspects, and intuition of CP-nets viewed as a formal method for describing and reasoning about concurrent systems. The perspective of pragmatics is our leitmotif, but at the same time in the context of CP-nets it is a kind of hypothesis of this thesis. This overview paper summarises the research conducted as an investigation of the hypothesis in the three areas of case studies, education, and extensions.The provoking claim of pragmatics should not be underestimated. In the present overview of the thesis, the CPN method is compared with a representative selection of formal methods. The graphics and simplicity of semantics, yet generality and expressiveness of the language constructs, essentially makes CP-nets a viable and attractive alternative to other formal methods. Similar graphical formal methods, such as SDL and Statecharts, typically have significantly more complicated semantics, or are domain-specific languages.research conducted in this thesis, opens a new complex of problems. Firstly, to get wider acceptance of CP-nets in industry, it is important to identify fruitful areas for the effective introduction of the CPN method. Secondly, it would be useful to identify a few extensions to the CPN method inspired by specific domains for easier adaption in industry. Thirdly, which analysis methods do future systems make use of

A distributed knowledge-based approach to flexible automation : the contract-net framework

Includes bibliographical references (p. 26-29)

Software Agent Architecture for Managing Inter-Organizational Collaborations

The growing importance of cooperation among organizations, as a result of globalization, current market opportunities and technological advances, encourages organizations to dynamically establish inter-organizational collaborations. These collaborations are carried out by executing collaborative business processes among the organizations. In this work we propose an agent-based software architecture for managing inter-organizational collaborations. Two types of agents are provided: the Collaboration Administrator Agent and the Process Administrator Agent. The former allows organizations setting up collaborations. The latter allows organizations executing collaborative business processes. A Colored Petri Net model specifying the role, which an organization fulfills in a collaborative process, is used to carry out the behavior of the Process Administrator Agent that represents the organization. Planning and execution of the actions of the Process Administrator Agents are driven by a Colored Petri Net machine embedded to them. Thus, Process Administrator Agents do not require to have defined at design-time the protocols they can support. In addition, we propose a model-driven development method for generating Colored Petri Net models from a collaborative process model defined as interaction protocol. Finally, an implementation of the agent-based software architecture and methods based on model-driven development are presented.La creciente importancia de la cooperación entre las organizaciones, como consecuencia de la globalización, las oportunidades actuales de mercado y los avances tecnológicos, alienta a las organizaciones a establecer en forma dinámica colaboraciones inter-organizacionales. Estas colaboraciones se llevan a cabo mediante la ejecución de procesos de negocio colaborativos entre las organizaciones. En este trabajo de investigación se propone una arquitectura basada en agentes de software para la gestión de colaboraciones inter-organizacionales. La arquitectura provee dos tipos de agentes: el Agente Administrador de Colaboraciones y el Agente Administrador de Proceso. El primer agente permite a las organizaciones a establecer colaboraciones. El segundo agente habilita a las organizaciones ejecutar procesos de negocio colaborativos. El rol que una organización desempeña en un proceso colaborativo es especificado mediante un modelo de redes de Petri coloreadas. Este modelo es usado para dirigir el comportamiento del Agente Administrador de Proceso, el cual representa a una organización. La ejecución de los planes y las acciones del Agente Administrador de Proceso son dirigidas mediante una máquina de redes de Petri coloreadas embebida en el agente. Entonces, los Agentes Administrador de Proceso no requieren tener definido en tiempo de diseño los protocolos que dan soporte a su comportamiento. Adicionalmente, se propone un método basado en el desarrollo dirigido por modelos para la generación en forma automática de modelos de redes de Petri coloreadas a partir de un modelo de procesos de negocio colaborativo definido como protocolo de interacción. Finalmente, la implementación de la arquitectura y los métodos basados en el desarrollo dirigido por modelos son presentados.Fil: Tello Leal, Edgar. Universidad Autónoma de Tamaulipas; MéxicoFil: Chiotti, Omar Juan Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo y Diseño (i); ArgentinaFil: Villarreal, Pablo David. Universidad Tecnologica Nacional. Facultad Regional Santa Fe. Centro de Investigacion y Desarrollo de Ingenieria En Sistemas de Informacion; Argentin

Proceedings of International Workshop "Global Computing: Programming Environments, Languages, Security and Analysis of Systems"

According to the IST/ FET proactive initiative on GLOBAL COMPUTING, the goal is to obtain techniques (models, frameworks, methods, algorithms) for constructing systems that are flexible, dependable, secure, robust and efficient. The dominant concerns are not those of representing and manipulating data efficiently but rather those of handling the co-ordination and interaction, security, reliability, robustness, failure modes, and control of risk of the entities in the system and the overall design, description and performance of the system itself. Completely different paradigms of computer science may have to be developed to tackle these issues effectively. The research should concentrate on systems having the following characteristics: • The systems are composed of autonomous computational entities where activity is not centrally controlled, either because global control is impossible or impractical, or because the entities are created or controlled by different owners. • The computational entities are mobile, due to the movement of the physical platforms or by movement of the entity from one platform to another. • The configuration varies over time. For instance, the system is open to the introduction of new computational entities and likewise their deletion. The behaviour of the entities may vary over time. • The systems operate with incomplete information about the environment. For instance, information becomes rapidly out of date and mobility requires information about the environment to be discovered. The ultimate goal of the research action is to provide a solid scientific foundation for the design of such systems, and to lay the groundwork for achieving effective principles for building and analysing such systems. This workshop covers the aspects related to languages and programming environments as well as analysis of systems and resources involving 9 projects (AGILE , DART, DEGAS , MIKADO, MRG, MYTHS, PEPITO, PROFUNDIS, SECURE) out of the 13 founded under the initiative. After an year from the start of the projects, the goal of the workshop is to fix the state of the art on the topics covered by the two clusters related to programming environments and analysis of systems as well as to devise strategies and new ideas to profitably continue the research effort towards the overall objective of the initiative. We acknowledge the Dipartimento di Informatica and Tlc of the University of Trento, the Comune di Rovereto, the project DEGAS for partially funding the event and the Events and Meetings Office of the University of Trento for the valuable collaboration