Research On Multi-Agent Cooperation Technology Based Contract Net Protocol

As an important researchful field of distributed artificial intelligence, Multi-Agent system is paying more and more an academe's attention, while cooperation is one of core problems of multi-Agent system research. The purpose of this dissertation is to improve classical Contract Net Protocol-one method of Agent cooperation. In the aspect of reducing system traffic and increasing speed of task execution, we do valuable discussion.This dissertation first introduces the concepts and technology, and mainly researches Multi-Agent cooperating way based Contract Net Protocol. Some shortcomings are found in Contract Net Protocol. In classical Contract Network Protocol, traffic load is higher and system efficiency is lower. Several parameters for mental state, such as trust degree, active degree, friend degree and signal degree, are introduced into Contract Net Protocol. By making full use of agent social attributes, dynamic combined choosing bids strategy is designed to reduce system traffic,and improves the efficiency of the system and the quality of the task. Threshold is set to limite the amount of bidding letters that agent receives. This refusing bids strategy is put forward to economizing system resource. Strategies above are applied to classical Contract Network Protocol, and then cooperation flow chart of improved Contract Network Protocol is pictured. Some experiments are made to simulate both classical Contract Net Protocol and improved Contract Net Protocol. And in the aspect of traffic and efficency, advantages of improved Contract Network Protocol are summarized by analyzing results of experiments.As an intelligent entity with sociality, Agent can have capability of communication. This paper analyzes parlance and semantics of KQML-a popular extensive communication language for Agent. In order to meet the needs of the Contract Network Protocol, we extend KQML's performatives and makes up performatives about task intercommunication. Besides, KQML's extension realizes the advanced, complicated and rotative cooperation on object and task among Agents. In the aspect of application, Agent cooperating way based improved Contract Net Protocol is...