“…For future study, researchers are encouraged to apply the basic principles of LDA ⁄ into incremental and/or hierarchical approaches [26] in order to handle partially observable and dynamic environments in real-time; mobile threat sources, mobile targets and dynamic gates, more realistic threat source attacks being among the properties of such environments. Moreover, utilization of non-uniform grid abstractions instead of uniform ones is also highly encouraged, since such improvement are expected to shrink the search space, and contribute to the performance of the algorithm drastically.…”
“…For future study, researchers are encouraged to apply the basic principles of LDA ⁄ into incremental and/or hierarchical approaches [26] in order to handle partially observable and dynamic environments in real-time; mobile threat sources, mobile targets and dynamic gates, more realistic threat source attacks being among the properties of such environments. Moreover, utilization of non-uniform grid abstractions instead of uniform ones is also highly encouraged, since such improvement are expected to shrink the search space, and contribute to the performance of the algorithm drastically.…”
“…Heuristic search is a general problem solving method applicable to a wide range of tasks [1], [3], [6], [7], [20]. Its efficiency depends on the quality of the heuristic evaluation function.…”
In this paper we analyze the existing defects of hierarchical and nonhierarchical path finding algorithm respectively in detail and present a hierarchical path finding algorithm based on the heuristic directing search approach which is used for promoting the nodes of lower level to higher level in the road network. The improved heuristic-hierarchical path finding algorithm was tested on road network of Xi'an city with a two-level hierarchy. The experimental results show that the heuristic based hierarchical path finding algorithm has been found to be over 25 times faster than the Dijkstra's algorithm and the ratio of the highest level road obtained by heuristic based hierarchical path finding algorithm is twice as much as the Dijkstra's algorithm. This means that the hierarchical path finding algorithm is suitable for the status of long-distance between origin and destination (O-D). We also propose a novel yet simple path finding strategy based on a threshold, that is, if the distance of O-D is less than the threshold which was obtained by means of statistical analysis the nonhierarchical path finding algorithm will be used, otherwise we use hierarchical path finding algorithm to find a near-optimal or satisfactory path in city road network. The testing results of Xi'an city road network show that the roads which were found out using this new path finding strategy are easy to be adopted by drivers.
“…In an attempt to combine quadtree technique and graphs, Autere (2002) created multiresolution maps, replacing the multisize grids of quadtrees by a graph representation. Two types of edges were used, one connecting neighbouring key places at the same resolution and another connecting configurations of different resolutions.…”
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.