基于时空棱柱的人员搜寻范围优化

在人员搜寻过程中,地理信息技术的应用能帮助缩小搜寻的空间范围、合理分配搜救资源,从而提高搜救效率、节约时间和资金投入。本文首先探讨了户外搜救过程中,地理信息技术在协助划定搜寻的空间范围和分配应急资源方面的应用;在此基础上,将时间作为连续变化的因素进行分析,以时间地理学对人员搜寻的时空范围进行优化;利用时空棱柱工具表达失踪对象和搜救资源各自的时空约束,继而确定他们各自随着时间变化的潜在活动范围;通过求解搜救资源和失踪对象的时空交集,来确定每个搜救资源最优的搜寻范围的外边界;通过将各资源的最优搜索范围的外边界进行综合分析,来求解在多个资源协作情况下的最小搜寻范围和各资源对应的搜索起点,实现对搜救资源的合理分配;最后,在ArcGIS平台上对该方法进行了实现和模拟。搜救案例展示该方法划定的人员搜寻范围在空间上更小,时间上更为精确,有助于分配救援资源和提高搜救效率。

The Optimization of the Search Area in a Search and Rescue Process based on GIS

Nowadays, people are more likely to participate in outdoor activities which results in the increase of people’s missing. In the process of search and rescue, the application of geographic information technology is able to help the search team to narrow the search area and allocate the search resources. As a result, GIS’ application improves the efficiency and saves time and cost. This paper firstly discussed the role of GIS in determining the search area and allocating the search resources in the search and rescue process. Then, based on time-geography tools, this paper optimized the search process on considering that time is a continuous variable. Space-time prism, which is one of the most important tools in time-geography theory, was used to express the spatio-temporal constraints of missing person as well as the search teams. The missing person can only be found in places where both the rescue team and missing person can reach at the same time. The aim of an optimization for the research and rescue process is to find the right place where both the missing person and the search team can arrive at the same time. In the spatio-temporal environment, this kind of place is the intersection of both sides’ space-time prisms. So, the search team only needs to search people in the intersection time and space of the prisms. In this way, the search area was narrowed and the time period was identified more precisely. When other search teams joins in the search process, the final search area is obtained after the intersection of every resource’s search area is calculated. At the same time, the search boundary for each resource is also obtained. Each resource can take actions according to its search boundary. This paper used ArcGIS software platform to achieve the optimization process. A search and rescue process using simulated data was presented afterwards. Compared with traditional buffer analysis method, the search area calculated from this method is smaller and the search time is more precise. This method can be used in combination with other methods to improve the efficiency, save cost, as well as allocate the research resources in a search and rescue process.