BSCTC:传感网的基于切向约束的B样条等值线查询算法

BSCTC:a contour query algorithm based on B-spline curves with tangent constraints for wireless sensor networks

针对目前传感网的等值线查询方法需要返回较多代表节点,代表节点选取的计算复杂度高且等值线还原结果不理想的情况,提出了一种基于切向约束(TC)的B条等值线(BSC)查询算法,简称BSCTC。该算法基于切向约束的2次B样条插值原理,首先选出等值线中的代表节点并传输代表节点信息给Sink,然后在Sink端对返回的代表节点进行分段还原,形成等值线。理论分析表明:BSCTC算法返回的代表节点期望数只是网络等值线节点数的39%,代表节点选取的计算复杂度为0(n)(n为等值线节点个数)。实验结果表明:与目前最好的DABC算法相比,BSCTC算法返回的代表节点数减少了53%,而且可形成更精确的等值线。

Considering that existing contour query approaches for wireless sensor networks suffer from heavy transmission due to the large number of representative nodes, large computational overheads and low recovery accuracy, this paper proposes a new contour query algorithm based on B-spline curves with tangent constraints, named the BSCTC algorithm for short. The BSCTS algorithm firstly elects some representative nodes in contours and sends relative information of them to the Sink according to the interpolation principle for secondary B-spline curves with tangent con- straint, and then the Sink recovers contours according to the information of representative nodes. The theoretical analysis shows that the expectation of the representative nodes returned by the BSCTC algorithm is only 39% of the number of the nodes in contours of sensor networks, and the complexity of representative node selection is O （n）. The experimental results show that when using the BSCTC algorithm, the number of the returned representative nodes can be reduced by 53% compared with the state-of-the-art DABC algorithm, and the more accurate contour map can be formed.