無線感測網路近年來廣泛應用於生態環境監控，提供一個密集的時間與空間上的監測，此為傳統監控生態方式所不及的。因為感測節點能量上的限制，如何有效節能的將感測資料傳送到基地台，延長感測網路的網路生存期間是相關研究努力的目標。

　　本研究提出一個新的叢集演算法，透過兩階段叢集首的選擇方式達到叢集首在時間和空間上的均衡分佈，以達到延長網路生存時間。在給予第一階段與第二階段排除範圍的叢集架構下，使單一回合中叢集首得以空間上均勻分佈，以及利用四種狀態分類可使感測節點在時間上均勻擔任叢集首，並且限定每回合叢集首蒐集叢集內資料回傳給基地台次數是固定的，讓各叢集首節點在穩定狀態所消耗的能量不會相差太多，如此必定能達到更佳的節能效果。

　　In recent years, wireless sensor networks are extensively employed in the environment monitoring. It provides intensive environment monitoring in temporal and spatial respects, while the traditional environment monitoring can not afford it. Due to the limited energy in sensor nodes, it is of researching goal that the life time of sensor networks is prolonged by transmitting the sensed data to the base station in energy-saving way.

　　We propose a new clustering algorithm which has cluster-heads be distributed evenly in temporal and spatial respects by two-phase cluster-head selection mechanism. With the restriction of the first-phase and the second-phase exclude distances, in each round, cluster-head can be distributed evenly in spatial respect. By classifying all the sensor nodes into four classes, all sensor nodes can become cluster-heads evenly in temporal respect. Furthermore, the number of transmissions of sensed data from cluster heads to the base station in each round is fixed to five, resulting in consuming almost the same energy for each cluster-heads in the steady state. Thus, our algorithm can save the energy significantly.

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