Abstract Emergency medical service (EMS) systems provide medical care to pre-hospital patients who need rapid response and transport. This paper proposes a modeling approach for joint relocation and districting strategies in EMS systems. This combined approach aims to increase the efficiency of EMS systems. We extend the nested-compliance model (which provides a relocation policy) to consider an upper bound on relocation time by partitioning the whole region into smaller sub-areas (districts). We analyze the decision regarding how to partition the service area into smaller sub-areas in which each sub-area operates independently under separate relocation strategies. Once the district solution is determined, a Tabu search is used to allocate stations and zones to districts and the optimal nested-compliance model solution is applied to each sub-area. The objective is to maximize the overall realized expected coverage. The performance of the combined relocation and districting policies are compared to a static policy (non-relocation and non-district) based on the adjusted maximum expected covering location problem (AMEXCLP) in a simulated system using real-world data. The numerical results show the benefits of our model over the AMEXCLP based on average realized coverage and the fraction of covered calls responded to by the first closest ambulance in the dispatching rank list.

中文翻译：

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使用 EMS 系统的嵌套合规模型进行联合搬迁和分区

摘要 紧急医疗服务 (EMS) 系统为需要快速反应和运输的院前患者提供医疗服务。本文提出了 EMS 系统中联合搬迁和分区策略的建模方法。这种组合方法旨在提高 EMS 系统的效率。我们扩展了嵌套合规模型（它提供了重定位策略），通过将整个区域划分为更小的子区域（区）来考虑重定位时间的上限。我们分析了关于如何将服务区划分为更小的子区域的决策，其中每个子区域在不同的搬迁策略下独立运作。一旦确定了地区解决方案，就使用禁忌搜索将站点和区域分配给地区，并将最优嵌套合规模型解决方案应用于每个子区域。目标是使总体实现的预期覆盖率最大化。在使用真实世界数据的模拟系统中，基于调整后的最大预期覆盖位置问题 (AMEXCLP)，将组合搬迁和分区策略的性能与静态策略（非搬迁和非区域）进行比较。数值结果显示了我们的模型优于 AMEXCLP，基于平均实现的覆盖范围和调度排名列表中第一个最近的救护车响应的覆盖呼叫的比例。