Continuous approximation models for rural transit network design

The purpose of this project is to discover new continuous approximation models for public transit network design, with a specific focus on rural areas where access to transit and coverage present significant challenges. Rural transit systems face unique constraints in connecting dispersed population centers while maintaining economic viability, which necessitates a modelling approach that addresses multiple competing objectives simultaneously. The continuous approximation paradigm is a quantitative method for solving logistics problems using a small set of parameters to model a complex system, which results in simple algebraic expressions that are easier to manage than (for example) large‐scale optimization models. As a further benefit, one often obtains insights from these simpler formulations that determine what affects the outcome most significantly. Although continuous approximation models have been used for over 60 years in logistics systems analysis, there has been very little research conducted on their application to problems in rural transit networks, likely due to their distinctive spatial characteristics and coverage requirements. Recent research demonstrates that limited flexibility yields disproportionate benefits in logistics systems. This project will combine tools from geospatial optimization, computational geometry, and geometric probability theory to formulate new models that will solve these problems. Furthermore, these models will identify which complementary infrastructure investments would most effectively increase transit availability and ridership in rural counties. The research outcomes include both theoretical advances in continuous approximation methodology and practical planning tools for rural transit agencies with limited computational resources.

• Record URL:
  • https://ncst.ucdavis.edu/project/continuous-approximation-models-rural-transit-network-design

Language

• English

Project

• Status: Active
• Funding: $100,000.00
• Contract Numbers:

  DOT 69A3552348319

  DOT 69A3552344814

• Sponsor Organizations:

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590

  National Center for Sustainable Transportation

  University of California, Davis
  Davis, CA  United States 
• Managing Organizations:

  National Center for Sustainable Transportation

  University of California, Davis
  Davis, CA  United States 

  University of California, Davis

  1 Shields Ave
  Davis, California  United States  95616

  University of Southern California, Los Angeles

  University Park Campus
  Los Angeles, CA  United States  90089
• Project Managers:

  Cliff, Sydney

• Performing Organizations:

  National Center for Sustainable Transportation

  University of California, Davis
  Davis, CA  United States 

  University of Southern California, Los Angeles

  University Park Campus
  Los Angeles, CA  United States  90089
• Principal Investigators:

  Carlsson, John

• Start Date: 20260401
• Expected Completion Date: 20270331
• Actual Completion Date: 0
• USDOT Program: University Transportation Centers

Subject/Index Terms

• TRT Terms: Network analysis; Public transit; Rural transit; Transportation planning
• Subject Areas: Planning and Forecasting; Public Transportation;

Filing Info

• Accession Number: 01985473
• Record Type: Research project
• Source Agency: National Center for Sustainable Transportation
• Contract Numbers: DOT 69A3552348319, DOT 69A3552344814
• Files: UTC, RIP
• Created Date: Apr 12 2026 11:45PM