This example visualizes a network of experts and their associated strategic technology topics (STPs) using an interactive force-directed graph. Users can toggle between a bubble chart and a network view with a button, and drag nodes to explore connections. The visualization employs `d3.forceSimulation` with charge, center, and collision forces to position nodes, while a zoom behavior allows panning and scaling. Node colors are assigned via a `d3.scaleOrdinal`, and the data originates from a nested JSON hierarchy processed with `d3.hierarchy`.