Large Graphs: Fast Cost Update and Query Algorithms. Application for Emergency Vehicles
This chapter presents a method that can be used to solve the shortest path problem in large graphs, together with arc cost updates. Our approach uses a contracted graph, which is obtained from the important nodes of the original graph. Every non-important vertex has one or more assigned important nodes as references. A reference node will help us to quickly find the arcs to be updated. The advantage of our method is that we can quickly update the contracted graph, so it can be safely used for future queries. An application of these algorithms can be used by emergency vehicles.
KeywordsShortest path problem Contracted graph Reference node Emergency vehicle
This work was supported by the Bilateral Cooperation Research Project between Bulgaria-Romania (2010–2012) entitled “Electronic Health Records for the Next Generation Medical Decision Support in Romanian and Bulgarian National Healthcare Systems”, NextGenElectroMedSupport.
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