1. Bus GPS processing
Route shapes learned from vehicle traces, on-map snapping with an along-route Kalman filter, and diversion detection with an evidence-based lifecycle. Measured on 38 days of the BODS SIRI-VM feed.
London Live technical notes
How london.pengrubin.com is built, written for people who work with the data. Hongwei Peng.
2. Tube position inference
In preparation: how train positions are inferred from arrival countdowns and how feed noise is handled.
3. Backend and running cost
In preparation: architecture, per-upstream budgets, memory and egress, and how each was reduced.