In this paper, we study the k $k$ -prize-collecting coverage problem by using aligned disks. Suppose U $U$ is a set of users, L $L$ is a horizontal line on the plane, and S $S$ is a set of points on the line L $L$ , w...
详细信息
In this paper, we study the k $k$ -prize-collecting coverage problem by using aligned disks. Suppose U $U$ is a set of users, L $L$ is a horizontal line on the plane, and S $S$ is a set of points on the line L $L$ , where each user corresponds to a coordinate point, with an associated profit and an uncovered penalty. The problem is to select a set D ′ $\mathcal {D}^{\prime }$ of disks whose centers are all in S $S$ such that the total profit of the users covered by D ′ $\mathcal {D}^{\prime }$ is at least k $k$ , and the objective value, which consists of the total cost of the disks in D ′ $\mathcal {D}^{\prime }$ plus the total penalty of the uncovered users in U ∖ U ( D ′ ) $U\setminus U(\mathcal {D}^{\prime })$ , is minimized, where the cost of disk D $D$ is r ( D ) α $r(D)^{\alpha }$ , α ≥ 1 $\alpha \ge 1$ is an attenuation factor, r ( D ) $r(D)$ is the radius of disk D $D$ , and k $k$ is a given profit bound. We first prove that this problem is N P $NP$ -hard even when all users are located on line L $L$ , α = 1 $\alpha =1$ and the penalty of each user is 0. We present a pseudo-polynomial-time algorithm. Finally, we present a fully polynomial time approximation scheme for the problem.
暂无评论