使用行動代理人在網際網路中收集資料時，我們需要將行動代理人由一個單一的源頭派送到網際網路上大量的資料源以收集資料。由於行動代理人系統通常是在網路應用層上運作而無法知道網路的實際架構；再加上網際網路的連線狀況並不穩定且無法有效預測，這使得有效率地派送行動代理人成了一項具有挑戰性的工作。我們之前的研究已顯示出在不同的網路狀況下應使用不同的行動代理人派送排程，才能減少完成工作的時間，以達到更好的效率。
在這篇論文中，我們以居間中心性發展出一相似度指標，藉以判別行動代理人派送排程的大致架構。有了相似度指標，就可針對當時的網路狀況選擇較適合的派送排程；亦可避免在網路狀況欠佳時，因為選擇了不適合的派送排程，使得行動代理人無法完成所有指派的工作。本論文亦證明了相似度指標的適用性與相關特性。

Abstract

Mobile agents are dispatched from a single host to a many different data sources spread over the Internet. Mobile agents systems normally operate at application layer and just have no knowledge about underlying network topology. Moreover, the connection of Internet is variable and unpredictable all the time. These reasons make dispatching mobile agents efficiently a challenging task. Research has demonstrated that different mobile agents dispatching schedules should be chosen at different situations in order to minimize the time tasks completed and upgrade efficiency.
In this paper, a Betweenness-centrality based approach, called Similarity Index, is proposed to distinguish the silhouette of mobile agents dispatching schedules. With Similarity Index, seemly dispatching schedules could be selected according to the internet situations at the time. Similarity Index can also prevent all the schedules are failed because we select too similar schedules when internet situations at that time are poor. Suitability and properties of Similarity Index are also confirmed in this paper.

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