Optimal transit service atop ring-radial and grid street networks: A continuum approximation design method and comparisons

摘要

Two continuum approximation (CA) optimization models are formulated to design city-wide transit systems at minimum cost. Transit routes are assumed to lie atop a city's street network. Model 1 assumes that the city streets are laid out in ring-radial fashion. Model 2 assumes that the city streets form a grid. Both models can furnish hybrid designs, which exhibit intersecting routes in a city's central (downtown) district and only radial branching routes in the periphery. Model 1 allows the service frequency and the route spacing at a location to vany arbitrarily with the location's distance from the center. Model 2 also allows such variation but in the periphery only.