Project Summary Approximating Network Design Problems on Directed and Undirected Graphs
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چکیده
Network design on directed graphs are problems that require to select a minimum cost directed subgraph of a given edge-weighted directed graph, under some constraints. One of the main goals of this proposal is to understand some of the most fundamental network design problems on directed graphs whose exact approximability status remains unclear for a very long time. Directed graphs appear frequently, when modeling the problem by an undirected graph is not enough (see, for example, [71]). Applications for which the graphs arising are naturally directed include questions related to the web graph (c.f., [68]), social networks graphs (c.f., [72]), dynamic graphs in artificial intelligence (c.f. [25]), and more.
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