General Meaning of the Methodology and the the system environment or the user requirements change.

4.1 General Meaning of the Methodology and the the system environment or the user requirements change.

Multi-agent systems are a fine tool to understand and manage

emergent phenomena, which are not welcomed – if not to say In the opinion of the author the following general evaluation of the

Results

feared of – in classical engineering, because they arise often un- methodology used and results obtained can be made and the con-

expectedly and are always hard to grasp and control. clusions listed below can be drawn:

Multi-agent systems are structured modular on principle, and Systems engineering is a well-established methodology to man-

can be constructed of individual modules or components. There- age complexity, the integration and application of multi-agent

fore it might be worthwhile, if there would be a possibility to systems as a tool for modeling and simulation of complex systems

exchange or trade prefabricated components to construct multi- even enhances this already very good methodology.

agent systems more easily, faster and cheaper by integrating work The sole application of analysis on its own is not enough, when

already done by others. But the realization of this idea depends we want to build new or optimize existing transportation net-

not least on common standards, which – at least as the author works, manufacturing processes and plants and other man made

knows at the moment – have to be established and agreed on, yet. constructs for industrial of commercial purposes. The analytic

With regard to more information on the construction and vali- thinking has to be accompanied if not to say led by design think-

dation of multi-agent systems in the present context, the reader is ing to successfully manage our factories and businesses. DeBono

referred to section 2.2 of this paper.

puts it this way: “You can analyze the past, but you have to design Not least, it should not be overlooked, that the proper commu- the future” [8]. Therefore the solitary application of multi-agent

nication and documentation of constructed models, the operating systems, which themselves mainly are tools for analysis, may be

principles of simulators used, as well as the results of the study not enough in many application cases.

and implementation phases of projects are important aspects for Mental models lead the way to formal and computer models.

the acceptance and successful application of multi-agent systems They are generated by vivid imagination and / or careful observa-

in industry and the further business world, too. tion of reality – an only ‘mechanical’ application of computer

models without deep understanding of the underlying reality and

4.3 Adaptivity of Logistics

its possibilities may be not enough to solve industrial and com- mercial problems.

Without getting involved deeper in the ramifications of adap- The ‘intelligent’ behavior of the whole (transportation) system

tivity—there are two basically different mind-sets of businesses may be seen as an emergent phenomenon arising from the coop-

and many flavors in between: the organization can be seen as an eration of the various agents, even if the individual agents are not

engineered machine or as a living organism (cf. [9], [17], [22])— very intelligent (cf. Brooks [5] and Ferber [11]). Basic examples

one can say that the ability to adapt to a business environment to illustrate this kind of phenomenon, which cannot be attributed

evolving at a ever faster pace is and will be an essential success to an individual component of the system alone, are e.g. the emer-

factor for survival and well-being of organizations. gent course of action of an individual transportation vehicle

This fact is valid not only for organizations as a whole, but is (which depends not only on its internal rule base, but develops out

passed on to its parts. Therefore it is necessary, that even the of the interaction with its environment, i.e. especially on the

transportation logistics of a manufacturing organization shows a course of action of the other transportation vehicles) and the ac-

high degree of adaptivity.

Object technology is an ideal foundation for building adaptive especially in the fields of parallel processing, intelligent agents business systems [22]. Because agent technology is based on

and multi-agent systems, and the industrial application of these object technology, this feature of object technology is transferred

technologies in the field of transportation logistics. to agent technology and multi-agent systems directly. And possi-

As already said and shown by a specific industrial application bly herein may lie the greatest advantage of agent technology and

example, intelligent objects and multi-agent systems are fine multi-agent systems in logistics: Software systems based on these

tools, which help in general to manage complexity and especially technologies may be considerable more adaptable compared to

to design and optimize the on-site transportation logistics of in- conventional monolithic software systems and therefore yield

dustrial manufacturing companies, e.g. engineering works and much more value for the user.

chemical factories. But the employment of multi-agent systems alone, which are mainly tools of analysis, is not sufficient, it has to be completed by a methodology for creative design of systems,

4.4 Work to be done

to find better ways of doing things.

As has been shown in section 4.2, the user friendliness is an Multi-agent systems will enable to construct and manage very important characteristic when constructing and using simulators

large and involved system models, which can nevertheless be an for industrial and commercial applications besides functionality.

approximation of actual by virtual reality of high quality. Through Parunak puts it this way: The tools used to develop systems for

this, for example they open up the possibility to model the logis- practical applications (i.e. running simulations for industrial use)

tics of the factories combined with the manufacturing processes must be packaged [19].

when required (Zeigler et al. have contributed to the underlying The multi-agent simulation system constructed and used by the

basic theory regarding this only recently [25]). This means there author, is at the moment based on textual operation. Even if it

will be tools, which can help to search for (and attain) global offers the complete functionality required at the moment, there are

optima of the whole factory, and to think another step further, some unfulfilled wishes regarding its ease of use.

even the whole supply chain.

For example there should be added a graphical user interface But the greatest advantage of multi-agent systems may be seen and component library, to make it easier for the user, to transfer

in their inherent adaptivity, which gives them a great advantage mental models into running computer models. It would be very

compared to the conventional monolithic systems when there is a comfortable to have a scanner combined with an interpreter to

fast evolving business environment.

read in the layout of the factory documented usually by existing To close with high expectations: Multi-agent systems and its maps or blueprints. In addition, an animation of the resulting

neighboring fields will probably help us to even better understand dynamics of the transportation process would be advantageous, to

the logic and organization principles underlying complex living make it easier for the user to understand the dynamics of the

beings, like individual biological organisms, organizations or system generated by the simulator and to present the system be-

whole societies (cf. Miller [17], Kelly [15]). It is to be hoped, that havior to his clients.

the relating bio-logical knowledge will merge with our The existence of the features given in section 4.2 are a prereq-

techno-logical know-how, so that we will be able to make our uisite, if the simulator should serve as a stand-alone system ap-

technical processes and socio-technical systems even more inte- plied by an user of a chemical company or engineering works

grated with itself and into the greater whole for the benefit of himself. De Geus sees this requirement, i.e. that managers of

everyone.

industrial companies are able to operate and ‘play’ with a simula- tor by themselves, to be very important for the methodology of

ACKNOWLEDGMENTS

modeling and computer simulation to be accepted along a wide front [9].

Even if the present paper has been written by only one author, the Besides, if necessary, there should be an enhancement of the

underlying project was influenced and supported by other people, individual agents, for example an extension regarding their rule

to whom I want to express my gratitude. base, to be able to test other, modified or refined operating poli-

First of all, I want to thank Mr. Michael Klussmann, Director cies. Another direction, which could be followed, is to extend the

of Operations of the “Chemische Fabrik Dr. Weigert”, Hamburg. present off-line use of the simulator into an on-line application for

His acute observations of his on-site transportation logistics and the purpose of on-line optimization and control of on-site transpor-

astute foreseeing of the regarding optimization potential gave rise tation processes (by control is meant above all a decision support

to the project. He supported our work with all his strength and for the drivers of the transport vehicles).

was always an excellent interlocutor. It was a pleasure to work for Not least, there is the possibility of developing other industrial

and with him.

and commercial applications based on the experience gained in Next, I want to thank Prof. Joachim Fischer and Dr. Klaus the construction and use of individual agents and multi-agent

Ahrens of Humboldt University, Berlin. By their book they gave systems, leading especially to the fields of supply chain manage-

me an excellent introduction to object-oriented event-based simu- ment and automation of trade, i.e. business-to-business e-

lation and opened up the world of discrete-event system simula- commerce.

tion and parallel processing for me. Especially, without the use of their simulation ‘kernel’ [12], this project would not have been possible.

Furthermore, I’d like to thank Dr. Reinhard Bachmann, De- To summarize and give the prospects in the opinion of the author:

4.5 Résumé

partment of Technology Assessment, Technical University of This paper and the underlying project strive to make a contribu-

Hamburg-Harburg. He drew my attention to the ideas of multi- tion in forging links between current findings of computer science,

agent systems, mechanisms of interaction between individual agent systems, mechanisms of interaction between individual

Distributed Artificial Intelligence. Cambridge, MA: MIT Press, 1999.

arising from the dynamics of complex systems.

[24] Zeigler, Bernard P.: Theory of Modeling and Simulation. Wiley, 1976.

As well, I want to thank Prof. Bernhard Lang, Professor for

[25] Zeigler, Bernard P., Herbert Praehofer and Tag Gon Kim: Theory of

Digital Multimedia Systems at the University of Applied Sciences

Modeling and Simulation: Integrating Discrete Event and Continuous Complex Dynamic Systems. 2 nd compl. rev. ed. San Diego, CA: Aca-

of Osnabrueck, Germany. In many discussions he has been a critic

demic Press, 2000.

of my work and source of good ideas especially concerning object- oriented modeling and programming and parallel processing on standalone computers and distributed networks.

Last, but not least, many thanks to my wife Hannelore for her patience and support when working the many hours acquiring and advancing the theoretical foundations of the project, which under- lie this paper.

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Negotiation Models for Agent Technologies in Logistics

RUN AND A. B

ORTIOLI A. P -S TAUDACHER :