解決感測覆蓋問題是在無線感測網路(WSNs)領域裡相當重要的問題之ㄧ。當感測節點被隨機佈置在監測範圍裡，通常在這區域裡會產生一些覆蓋空洞(coverage hole)。或著，由於一些感測節點的耗進或一些事件的發生而導致在一個完全被覆蓋住的監測區域裡產生了一些覆蓋空洞(coverage hole)。舉例而言，在戰場裡一些炸彈的爆炸。為了維持任何兩個感測節點間的覆蓋區域(coverage area)及連接性(connectivity)，一些感測節點應該根據一些規則去重新覆蓋已存在的覆蓋空洞。在這篇論文中，我們提出了稱為混合虛擬力演算法(Hybrid Virtual Force Algorithm, HVFA)，進而利用一些感測節點去移動(mobility)及放大能量階級(increasing power level)而重新覆蓋已存在的覆蓋空洞。在HVFA中，我們根據吸引力及排斥力進而訂出了一些規則去決定一些邊界感測節點（boundary node）去運行移動、以及另一部份的邊界感測節點去放大能量階級，進而去重新覆蓋原有的覆蓋空洞。

Solving sensing coverage problem is one of the important issues in wireless sensor networks (WSNs). Usually there are some coverage holes when the sensor nodes are randomly deployed in the monitoring area. Or, a fully covered monitoring area may be created some holes by some of sensor nodes were died or some events happened. For example, the bombs explored in the battleground. In order to maintain the coverage area and connectivity between any pair of sensor nodes, some of sensors nodes should recover the coverage holes based on some rules. In this paper, we proposed a algorithm is called Hybrid Virtual Force Algorithm (HVFA) to recover the coverage holes using some of sensor nodes operate mobility or increasing power level. In HVFA, we made some rules to decide some of boundary sensor nodes to operate mobility, and some part of them to increase power level for recovering the coverage holes based on attractive force and repulsive force.

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