Abstract
With development of Internet and technology, the traditional market has become an electronic market, and the value of trading has become more than a traditional market. The SME e-commerce has been grown rapidly, and more businesses have used the e-commerce for selling and buying goods or services. Consequently, most of the plastic e-marketplaces only allow the large companies to search the product and then contact the other large companies by email or phone. The e-marketplace needs an automated or intelligent agent in order to automated purchasing consortium among the SMEs. The consortium agents allow SMEs to make purchasing consortium by exchanging electronic messages in a multi-agent system. In addition, most of the e-marketplace does not support the purchasing consortium. This paper implements an automated purchasing consortium by applying Modified Knapsack Problem Algorithm, and by eliminating the broker agent in the consortium. Also, the efficiency of the simulated system in the plastic market is demonstrated by a series of simulations in which the result is Modified knapsack Algorithm Consortium and Exactly Consortium.