無線感測網路因為其應用的廣泛性在近年來受到許多研究團隊的注意，其應用有：核子反應爐監測、災難現場監視控、工廠溫度監測等等。而在這些應用之中，最重要的問題就是極值監測。因此，設計一個節能的極值監控演算法便成為了我們的研究主題。在過去的研究證明了Hierarchy Adaptive Thresholds (HAT) 可以有效率的進行極值監測。HAT利用樹狀結構來過濾掉不可能成為極值的數值。更甚者，HAT還可以利用這個結構來過濾掉不必要的詢問封包(Query Packets)。然而，HAT雖然在極值監控有傑出的表現，它依然有許多可以被改進的空間。我們提出一個演算法不止可以像HAT一樣可以利用樹狀結構過濾掉不必要的封包，而且我們會依據過去的歷史資料來進行各個感測器的回報速率調節。除此之外，我們還利用分散回報的方式來減輕MAX node的父節點的流量負擔。更甚者，我們還利用適時的傳送調節速率的封包而不是隨時隨地都傳送調節速率的封包來降低我們所產生出來的額外能量消耗。根據我們的實驗指出，本篇論文所提出的演算法可以比HAT降低15%到19%左右的封包傳送。而因為這些減少傳送的封包所產生的錯誤也可以維持在1%之下。另外，我們也利用分散回報來降低MAX node所產生的龐大封包量。再者，我們還利用線性回歸以及CUSUM來判斷我們什麼時候該傳送調節速率的封包。利用這樣的方法，我們可以減少相對於隨時隨地傳送調節封包的方式大約60%到70%左右的額外能量消耗。

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