  Parallel betweenness computation algorithms are proposed and implemented in a
graph database for power system contingency selection. Principles of the graph
database and graph computing are investigated for both node and edge
betweenness computation. Experiments on the 118-bus system and a real power
system show that speed-up can be achieved for both node and edge betweenness
computation while the speeding effect on the latter is more remarkable due to
the data retrieving advantages of the graph database on the power network data.
