Countless device in our dailies lives use electricity. This number continues to increase as time passes by. To power these new devices we need ever more energy. The main source of electricity for the majority of devices is from a power grid. These massive physical networks can span across different countries and provide electricity for the majority of the world.
Source: https://en.wikipedia.org/wiki/File:HVDC_Europe.svg
For a graph of a power grid we can take the … to be nodes and the cables between them to be edges. We can also measure the electrical current through an edge as the weight of that edge. We can use graph flow methods to measure the importance of different edges, and asses whether the given infrastructure is enough to handle the load. Occasionally there can be blackouts, which can occur as the result of some edge between two nodes being removed. Larger blackout can occur as the result of cascading failures occurring after several edges fail. These failures can result in increased flow on several edges, which may lead to these edges failing as well increasing the size of the blackout.
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