TRB’s Transportation Research Record: Journal of the Transportation Research Board, No. 2130 includes 18 papers that explore passenger car equivalents based on capacity variability, user perceptions of signalized intersection level of service—prediction based on fuzzy neural networks, estimating freeway work zone capacity, level of service of freeway weaving segments, and capacity of freeway weaving segments.

This issue of the TRR also examines left-turn delay estimation, left-turning vehicles at a two-way stop-controlled intersection, U-turn capacity at unsignalized median openings, assessing quality of progression on signalized urban streets, peak flow variations, capacity of turbo roundabouts, effect of phase countdown timers on queue discharge characteristics, Taiwan's Shea-San Tunnel capacity, delay pattern estimation for signalized intersections, performance measures for truck level of service, capacities of unsignalized intersections, simulation of work zone capacity values, and model-based estimation of arterial link travel times.