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Coordinating, Developing, and Delivering Highway Transportation Innovations

This report is an archived publication and may contain dated technical, contact, and link information
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Publication Number:  N/A    Date:  July 1998
Publication Date: July 1998


Twopas Model Improvements

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The proposal for the NCHRP 3-55(3) project "Capacity and Quality of Service of Two-Lane Highways" was submitted in May 1995 and the contract was awarded to MRI in the early fall of 1995. A working plan was submitted in October 1995 and work on the project began immediately.

The project was divided into eight major tasks with the first four tasks being designated as Phase I and the last four tasks being designated as Phase II. The eight major tasks were:

Task 1 Identify Capabilities and Deficiencies of Existing Methods
Task 2 Develop an Improved Conceptual Framework for Capacity and Level of
Service Analysis
Task 3 Select a Suitable Simulation Model and Identify Desirable Functional
Task 4 Prepare Interim Report
Task 5 Collect and Analyze Data
Task 6 Enhance, Calibrate, and Validate the Selected Simulation Model
Task 7 Develop Revised Capacity and Quality of Service Analysis Procedures for
Two-Lane Highways
Task 8 Prepare Final Report

This report deals with Task 6 "Enhance, Calibrate, and Validate the Selected Simulation Model". The objective is to report accomplishments on TWOPAS model code upgrading and documentation and to document all TWOPAS model improvements.