無線感測網路，是由感測元件與無線通訊元件搭配的裝置所組合成的網路，適合佈建在大範圍或惡劣環境中，用於蒐集裝置周邊的環境資訊，並透過無線網路，定期回報資訊給基地，由於環境的關係，裝置在佈建後通常難以得到後續的電力補充，在這樣的情況下，每個裝置的存活時間將變成有限，這樣的情況下，如何最大化整體網路的存活時間便成為重要的課題。
本篇論文的目的在於探討如何在多重資料匯集樹中尋找共同的重度負載節點，使得我們找到的共同的重度負載節點能符合定義。

The wireless sensing network is a network composed of devices with sensing components and wireless communication components. It is suitable for deployment in a wide range or harsh environment, and is used to collect environmental information around the device and through the wireless network. Regularly return information to the base. Due to the environmental relationship, it is often difficult to obtain subsequent power supplements after the installation. In this case, the life time of each device will become limited. In this case, how to maximize the life time of the network has become an important issue.
The purpose of this paper is to explore how to find common heavily load nodes for multiple data aggregation trees, so that the common heavily load nodes we find can conform to the definition.

目錄
1 Introduction 4
2 Sensor Network Model 5
3 Find Same Rset Problem 8
3.1 Definition of Normalized load 8
3.2 Definition of R 9
4 Algorithms 10
4.1 Definition of improvement 12
4.2 Classification of Nodes 12
4.3 Base Algorithm 13
4.4 Post-Processing Algorithm 15
4.5 Random Initial Tree Algorithm 16
5 Simulation 18
5.1 Performance of Post-Processing Algorithm 20
5.2 Impact of Density 21
5.3 Impact of Node Number 23
5.4 Performance of repeat different random methods 26
6 Conclusion 29
References 30

References
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