In this work, we study scheduling in star data gathering networks with background communications. The worker nodes of the network hold datasets that have to be transferred directly to the base station. The communication speed of each link changes with time, due to other applications using the network, independently of the speeds of other links. Our goal is to gather all data within the minimum time. We show that while the preemptive version of this problem can be solved in polynomial time, the non-preemptive variant is strongly NP-hard. We propose for it an exact exponential algorithm based on dynamic programming, several polynomial time heuristics and local search algorithms. Theoretical performance guarantees and the existence of dominance relations between the heuristics are studied. The performance of the proposed algorithms is also tested in a series of computational experiments.

中文翻译：

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在具有后台通信的数据收集网络中进行调度

在这项工作中，我们研究了具有后台通信的星形数据收集网络中的调度。网络的工作节点持有必须直接传输到基站的数据集。由于使用网络的其他应用程序，每个链接的通信速度随时间变化，与其他链接的速度无关。我们的目标是在最短的时间内收集所有数据。我们表明，虽然这个问题的抢占式版本可以在多项式时间内解决，但非抢占式变体是强 NP-hard 的。我们为此提出了一种基于动态规划、多项式时间启发式算法和局部搜索算法的精确指数算法。研究了启发式算法之间的理论性能保证和优势关系的存在。