Research On The Multi-Agent Task Allocation Mechanism Based On Extended Contract Net

Task allocation has become an important issue of the complex systems with the distributed,open,intelligent and social characteristic for the collection of operation. However,continuous changes of internal and external environment and dynamical changes of the capacity of members may give tasks allocation solving difficulty. Multi-Agent System(MAS) is to study how to make one or more entities complete complex or tedious tasks without guidance through mutual cooperation,coordination and consultation.The emergence of MAS brings a new way to solve such issues as above.Contract Net Protocol(CNP) is a classic coordination strategy of allocation of resources and tasks.The basic idea is to allocate tasks and complete the contractual relationship through the market mechanisms like "tendering-tender-awarding" with lower costs and higher qualities.Generally,the traditional contract net model does not place any limits on competitors,but the broadcast of task announcement tends to consume much communication load when the agents are excessive.On the other hand,Agent can deal with unrestricted access to any bid,which makes a lot of communication become unnecessary behavior.In order to reduce the costs,simplify Agent decision-making process and improve the efficiency of solving problem,this paper introduces several mind parameters,such as familiar,trust and active,to restrict the scope of tender by adopting the "acquaintance mechanism",sets buffer pool for each Agent to limit the number of bids and propoes the modified rules to evaluate the quality of tasks.Based on the improved contract net method,a multi-Agent task allocation strategy based on extended contract net is presented,which ensures a better negotiation quality,designs and implements the task allocation algorithm.Finally,on this basis of above,the task allocation mechanism of multi-Agent based on extended contract net is applied to the steel procurement management system,in the form of an instance,to achieve the issue of supplier selection.Task allocation of multi-Agent based on extended contract net has been covering MAS,organization theory and other fields.The research of further improvement and development is still to be done,which causes an increasing number of researchers for concern.