在一個給定的區域如何去佈署感測器是一個重要的研究領域，因為它影響無線感測器網路的效能甚巨。傳統的演算法，把感測器網路區域均視為相等的重要性，很多的感測器佈署演算法都著重在如何用有限的感測器或是有限的預算去覆蓋到最大的感測區域面積。然而，在很多的應用裡，例如消防系統、軍防監視、輻射偵測、生化攻擊偵測等等，所監視的地方應隨著每個不同區域的重要性給予不同的優先權：愈重要的區域應該擁有愈高的權值與愈高的優先性。在這篇論文裡，我們提出權值區域感測器覆蓋問題的概念，感測器佈署不再是以覆蓋到最大的區域面積為考量，而是以覆蓋到最大的權值總和為目標。我們在論文裡證明了這個問題屬於NP-Complete，並提出一個接近最佳解的演算法。

The deployment of sensors on a given field is an important issue that affects wireless sensor networks. Traditionally, all areas of a sensor field are equivalent, and multiple deployment algorithms are used to maximize the area covered by a given number of sensors or a certain budget. However, in many applications, such as fire control system, battlefield surveillance, detection of nuclear, biological, or chemical (NBC) attack, and other things, the areas must be weighted based on priority of deployment: the more critical the area, the higher the weight and the higher the priority. In this thesis, we introduce the problem of the weighted sensor field, and determine the maximum weight of the coverage area by deploying a given number of sensors on a given weighted field. We prove that this problem is an NP-Complete problem. And propose an algorithm to find a near-optimal solution for the weighted field sensor covering problem.

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