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  Instead of extending the SINE platform to include the new extensions to the SiFA paradigm and the negotiation capabilities, COSINE was built from scratch using a slightly different approach. The reason for this was mainly due to time limitations. Developing the wine glass designer using CLIPS directly rather than the SINE platform was a simpler task than modifying the SINE code.

SINE used COOL (CLIPS Object-Oriented Language) to define a class hierarchy of agents, design objects, points of view, and targets. This enabled inheriting common features of classes when defining objects. For example, when defining a selector agent, the data and procedures common to all selectors was simply inherited.

COSINE uses only the rule based portion of CLIPS and does not have any classes and objects. While making the system simpler in terms of understandability, this does not allow for inheritance. Although all agents have similar rules, there is no way of inheriting the common code. Many rules are repeated in all agents with minor modification. This is a major drawback.

An advantage of the simplicity of COSINE is that it is easy to spot rule patterns that occur in all agents of the same type. These similar patterns allow for the building of a knowledge acquisition tool so that designers of agents do not need to write rules, but enter the knowledge using a graphical user interface. The knowledge acquisition tool generates rules automatically. Although such a tool has not been built yet, it is part of the ongoing research on SiFA based systems.

Sample rules from COSINE can be found in Appendix A and sample outputs can be found in Appendix B.

Ilan Berker
Thu Apr 27 16:25:38 EDT 1995