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From page 158... ... 160 Mathematical and Procedural References Method for Synthesizing a Distribution of Consistent Path-Dependent Origin– Destination Travel Times from the Known Distribution of Link Traffic Counts Problem This method is suggested for the generation of origin– destination (O-D) travel time distribution for the base year, which is needed for calculating travel time reliability measures. Read the entire page →
From page 159... ... 161 When forming the network scenarios from link count distributions, two main principles should be followed: • The observed distribution of traffic counts for each link should be preserved across the network scenarios. This can be easily achieved by constructing scenarios as combinations of permutations of the numbered counts 1, 2, . Read the entire page →
From page 160... ... 162 In the program formulation, this measure is squared (because independence is violated by both positive and negative correlations) , weighted by the demand, and summed over all pairs of O-D cells. Read the entire page →
From page 161... ... 163 introduced in Chapter 4 and applied to the New York Regional Best Practice Network. The basic model assumptions were stated in Chapter 4 within the Integrated Model Framework to Evaluate Pricing and Reliability section. Read the entire page →
From page 162... ... 164 problem, under a given road pricing scheme, to obtain a timevarying route flow vector satisfying the MDUE conditions. Based on the aforementioned NCP formulation (Equations A.19–A.22) Read the entire page →
From page 163... ... 165 Therefore, a projected gradient-based descent direction mode flow update scheme is as follows. Read the entire page →
From page 164... ... 166 Simulation-Based Iterative Solution Framework The TDMSUE–MDUE problem consists of finding both equilibrium travelers' mode choice and equilibrium vehicles' route choice with a given time-dependent traveler demand. The TDMSUE problem is solved by a projected gradient-based descent direction method. Read the entire page →
From page 165... ... 167 Step 1. Input and Initialization 1.1 Input: Time-dependent multimodal traveler O-D demand with individual characteristics (income, auto ownership, and purpose) Read the entire page →
From page 166... ... 168 • 2 other counties from New York State; • 13 counties from the North Jersey Transportation Planning Authority (NJTPA) area; • 1 other county from the state of New Jersey; and • 2 counties from the state of Connecticut. Read the entire page →
From page 167... ... 169 Figure A.3. DYNASMART-P model of the New York network. Read the entire page →
From page 168... ... 170 Table A.1. Input Files for DYNASMART-P Input File Description Status Network Data xy.dat Contains the coordinates of the physical nodes to be used by the DYNASMART-P GUI Optional linkxy.dat Contains links' starting and ending nodes. Read the entire page →
From page 169... ... 171 TransCAD data Google Earth and other sources Manual corrections on TransCAD and output of data Use the conversion tool to prepare input data for DYNABUILDER Create network using DYNABUILDER Run the network on DYNASMARTP Properly running? Y Manual correction possible? Read the entire page →
From page 170... ... 172 Preparation of DYNASMART-P data files for the simulation and graphical user interface (GUI) consists of several steps. Read the entire page →
From page 171... ... 173 dynamic traffic assignment constraint. Specifically, the upperlevel problem seeks to estimate the dynamic O-D trip desires based on given link counts and flow proportions, subject to non negativity constraints for demand variables. Read the entire page →
From page 172... ... 174 Three types of input are required for this task, namely the link proportions, link observations, and an initial estimate of the O-D demand matrix (target matrix) Read the entire page →
From page 173... ... 175 To evaluate the performance of the procedure, the root mean squared error between observed link volumes and simulated link volumes is used as an overall measure of effectiveness. Validation against individual link counts was performed for selected links. Read the entire page →

From page 158...

... 160 Mathematical and Procedural References Method for Synthesizing a Distribution of Consistent Path-Dependent Origin– Destination Travel Times from the Known Distribution of Link Traffic Counts Problem This method is suggested for the generation of origin– destination (O-D) travel time distribution for the base year, which is needed for calculating travel time reliability measures.