We are pleased to publish a special issue of Networks that contains a selection of high-quality papers presented at two conferences held in 2019: INOC 2019 (Avignon, France) and EURO 2019 (Dublin, Ireland). The articles in this June 2021 issue provide the following contributions:
• complexity results and specialized algorithms for the minimum color-degree perfect b-matching problem on edge-colored graphs,
• optimization of the expansion plan of a mobile telecommunication company, taking into account the realization of various technologies,
• complexity results and approximation algorithms for "scheduling by edge reversal" to optimize concurrency of a distributed system,
• solution approaches for semi-stable routing in software-defined networks in order to enhance network reconfiguration,
• complexity analysis of an undirected two-commodity integral flow problem, certain disjoint path problems, and the strict terminal connection problem,
• exact and approximate solution approaches for the densest subgraph problem, especially for very large instances,
• analysis and algorithms for the weighted target set selection problem, a fundamental viral marketing problem in social networks.
We trust that the readership of INFORMS will find these articles to be of interest. Two of these papers are published Open Access.
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Douglas Shier
Bruce Golden
Editors-in-Chief, Networks
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