無線感測器常常被放置在不易到達的區域且去收集所需的環境參數，無線感測器被放置在不友善的環境中，透過多點跳耀(multihop)的方式將感測器所感測的資料回傳至基地台，為了減少傳送資料量，資料的聚集和融合技術，被廣泛的使用在無線感測器網路中，同時降低感測器能源的消耗，隨著感測資料的收集，感測器能源將會耗盡且有可能因為外在環境的影響使得感測器發生故障，造成網路不連通而有可能形成一群感測器並無法和觀測點(sink)連通，使得感測資料無法回傳至觀測點，造成感測資料流失，所得的查詢結果也會因為回傳的感測資料不完全而影響查詢的正確性。
目前很多相關研究者著重於發展增進無線感測網路效能的方法。但對於感測資料的流失則較少被討論到。在本論文中我們提出無線感測網路中發生網路斷裂時的暫存策略，當一群感測器發生網路不連通時，則選擇合適的感測器去暫存聚集資料並等待網路連通後將資料回傳，利用此策略可以降低感測資料的流失。

Wireless sensors are often placed in unattended area for collecting interesting data which will be delivered later through the multi-hop wireless network.In wireless sensor network, data aggregation and data fusion are very effective to reduce the amount of transmission which saves the energy of sensor nodes.When sensors continue to collect sensor data, the energy of sensor might exhaust and sensor might be a fault because of other external factors. There may exist some network broken. In this situation, some sensed data may be lost due to the network broken.
Recently, many researchers focus on developing many methods to improve the efficiency of wireless networks; however the issue of data lost is seldom discussed. In this paper, we propose the temporal storage method in which existed network broken in wireless sensor network. When sensor network is temporally not working, the sensor will start to store aggregation data temporally until sensor network rework and sensor will deliver aggregation data to base station finally. Using our method will reduce data lost greatly.

第一章 緒論 5`
1.1前言 5
1.2無線感測網路環境 7
1.3研究動機 10
1.4論文架構 12
第二章 相關研究 13
2.1 13
2.1.1無線感測網路 13
2.1.2 感測器硬體構造及功能 14
2.2路由協定 20
2.3容錯機制 25
2.4資料中心暫存 31
第三章 研究方法 35
3.1 問題描述 35
3.1.1問題背景 35
3.1.2問題想法 40
3.2無線感測器網路環境 43
3.3方法架構 46
3.4 快取子節點 50
3.5選取暫存節點 52
3.6選取聚集節點 62
3.7重選暫存點與回傳機制 65
第四章 實驗結果與分析 67
4.1軟硬體環境 67
4.2參數設定 68
4.3衡量指標 70
4.4結果分析 70
第五章 結論與未來發展 79
5.1 結論 79
5.2 未來發展 79

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