無線感測網路是藉著連通每一個有能力去收集、處理和儲存環境資訊並透過無線通信溝通的感測器所形成。這些特性允許無線感測網路被使用在一個寬廣範圍應用。在很多的應用裡，例如環境監控、軍防監視、輻射偵測、生化攻擊偵測等等，重要區域和一般區域必須被適當地區分開來，如果要偵測區域很大或是提供的預算無法去蓋滿整個偵測區域的話，監控重要區域遠比一般區域是更實際和有效率。在本論
文中，研究使用最少感測器來建構蓋滿重要區塊無線感測網路，稱為覆蓋重要區塊(CRITICAL-GRID COVERAGE)。由於覆蓋重要區塊是NP-Complete的問題，所以為了覆蓋重要區塊提出了四個演算法。根據實驗顯示本論文所提出的演算法針對覆蓋重要區塊有較好的解決方法。

Wireless sensor networks are formed by connected sensors that each have the ability to collect, process, and store environmental information as well as communicate with others via inter-sensor wireless communication. These characteristics allow wireless sensor networks to be used in a wide range of applications. In many applications,
such as environmental monitoring, battlefield surveillance, nuclear, biological, and chemical (NBC) attack detection, and so on, critical areas and common areas must be distinguished adequately, and it is more practical and efficient to monitor critical areas rather than common areas if the sensor field is large, or the available budget
cannot provide enough sensors to fully cover the entire sensor field. In this thesis, the problem of deploying the minimum sensors on grid points to construct a wireless
sensor network fully covering critical grids, termed CRITICAL-GRID COVERAGE, is studied. Since CRITICAL-GRID COVERAGE is NP-Complete [16], four heuristics for CRITICAL-GRID COVERAGE are proposed. Simulations show that STBCGCA
the proposed algorithm provides a good solution for CRITICAL-GRID COVERAGE.

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