Lexington Area TransCAD Travel Demand Model July 22,
Lexington Area TransCAD Travel Demand Model July 22, 2003 Kentucky Traffic Model Users Group Meeting Kyeil Kim, Ph.D. Bernardin, Lochmueller & Associates, Inc. Main Features
Consists of separate time-of-day (TOD) models Realistic free-flow speed based on a speed survey and HCM-based signal delays Varying capacities by TOD for reversible lanes Model parameters are based on recent travel survey and KYTCs HIS database. 2-stage assignments: Initial and Feedback User-friendly model GUI Model Area Roadway Network Incorporation of KYTCs HIS and geometric/operations data
All MINUTP network attributes FHWA functional class, posted speeds, etc. Number of lanes, reversible lanes & bike lanes Area type, shoulder widths, median type, etc. Traffic signals & multi-way stops (signal priority, multiple signals) Turn prohibitors TAZ DB Total 489 zones Internal zones = 445 zones External zones = 44 zones
51 data attributes Date related to population and household Employment by SIC code Student population, group quarters & school enrollment Vehicle ownership Key data for estimating trip productions and attractions Speed/Capacity Estimation Free-flow speed, peak-hour capacity & daily capacity A special GIS-dk program to estimate directional capacities by TOD & free-flow speed Consideration of changes in reversible lanes by TOD
Free-flow speed = f (functional class, posted speed, number of lanes, facility type, delays on interrupted facilities) Daily capacity = f (functional class, number of lanes, facility type) Peak-hour capacity = max. service flow * adjustment factors where, Adjustment factors = f (geometric data, functional class, facility type, area type, delays on interrupted facilities) Speed/Capacity Estimation (Contd) Delays on interrupted facilities HCM 2000 procedure delay/veh = uniform delay * PF + incremental delay + initial queue delay 2 where, PF = progression factor type, g/C)
1 f g(arrival 0.5C= C 1 min 1, v c g C uniform delay = Varying g/Cs and PFs by signal priority and multiple signals Lexington Model GUI Lexington Model GUI Trip Generation Six internal trip purposes:
- HBW, HBK12, HBU, HBO, NHBW & NHBO Trip production - Cross-classification technique - Data: The 2000 Knoxville Household Travel Behavior Study, The 1999 Indiana University Travel Demand Survey - Analysis of Variance (ANOVA) and non-parametric correlations techniques to identify the predictor variables for various trip purposes - Stratification curve: distribution of households in a zone over various levels of the predictor variables Trip Generation (Contd) Trip production model Trip Purpose
HBU University Enrollment Population Retail Employment Commercial & Govt Employment Other Employment Population Retail Employment Commercial & Govt Employment Other Employment 1 .1168 .8257
.0408 .0137 .0575 .7593 .0846 .1053 HBO NHBW & NHBO Trip Distribution Doubly-constrained Gravity model for the 6 internal trip purposes & E-I trips
Friction factors - Initial factors from the old MINUTP model - Fitting to Gamma function for smoothing the factors - Adjustment of Gamma parameters to arrive at correct trip lengths by trip purpose Socioeconomic (or K) factors Vehicle Occupancy Vehicle occupancy rates by trip purpose HBW 1.09 persons/vehicle HBK12 1.96 persons/vehicle HBU 1.20 persons/vehicle HBO 1.83 persons/vehicle NHBW 1.17 persons/vehicle NHBO 1.75 persons/vehicle
(Source: The 2000 Knoxville Household Travel Behavior Study) Time-of-Day AM peak (06:30~09:00); Midday peak (12:00~13:30); PM peak (15:30~18:00) and Off-peak TOD factors - Split the 24-hr trip table into tables by TOD - by trip purpose Directional factors - Convert trip tables in a production-attraction format to origindestination tables - by trip purpose and by TOD Data Source: the 2000 Knoxville Household Travel Behavior Study External Trips
44 external stations E-E trips The 1994 O-D survey by Wilbur Smith Associates Most of E-E trip interchanges except for the interstate and US60 exchanges Kentucky Statewide Travel Model via critical link analysis E-E trip interchanges for the interstate and US60 external stations Modlin Equations A check of reasonableness E-I trips = ADTs - E-E trips at each external station 27 stations of the 44 stations carry through trips Traffic Assignment Time-of-day user equilibrium assignments - separate AM-peak, Midday-peak, PM-peak & Off-peak assignments
Improved free-flow speeds and varying capacities by TOD by reversible lanes Separate volume-delay functions (defaults) Unsignalized facilities = 0.20; = 10.0 Signalized facilities = 0.05; = 10.0 Feedback assignment Feedback Loop 24-Hour Average Speed Gravity Model TOD Trip Table Factoring
AM-peak Assignment Midday-peak Assignment PM-peak Assignment 24-Hour Weighted Average Congested Link Speed Off-peak Assignment
CAL_REP Assignment post-processor written in GIS-dk and incorporated in the GUI Various error statistics by functional classification, volume group, screenline, cutline and specific corridors Error statistics total counts, average counts, counts standard deviation total loadings, average loadings, loadings standard deviation % root mean square error mean error, % error total counts VMT, total loadings VMT, % VMT error Assignment Results
CAL_REP Report Loading % error = -1 % Loading VMT error = 0.9% % RMSE = 25% Interstate = 0.03% (% error); -2.6% (VMT error) Urban Principal Arterial = -1.3%; -3.1% Urban Minor Arterial = -3.8%; 3.7% In Progress Model runs for future years and post-processing 2030 with committed projects only 2010 with committed plus Plan projects scheduled for completion by 2010
2020 with committed plus Plan projects scheduled for completion by 2020 2030 with all projects in the current LRP Multinet handling feature in GUI for efficient network data THANK YOU!
Every time a new filter is added you will need to click "Find" again. Click on the "Clear" button to clear current search. ... Select Agency and Division Location, Then type in Vehicle (if applicable), Service Requested (please explain in...
The Statistics of Time Transfer. Introduction. Time transfer is the process of transmitting time information from one place to another. It can also be used to convey frequency information since frequency is the rate of change of phase. The performance...
Do you think having an education is important? If so, why? Education gives you the knowledge and skills that increase your ability to meet your basic needs, widen the range of options open to you in every sphere of life,...
based on Car-to-Car Communication Sasan Dashtinezhad, Tamer Nadeem Department of CS, University of Maryland ... road inner points We subdivide the road segments into equally distant reference points for location precision Road Identification Identify closest points to GPS location (using...
Simulation and heuristic solutions to NP complete problems. Student projects in simulation, field programmable gate arrays, and automated testing. Externally funded. Service. Working for CIO Dr. Ray Ford as IT/Legal advisor. Promoted to Associate Dean. As Department Chair focused on...
Beauty Of Elastic Search. In Elasticsearch, all data in every field is indexed by default. That is, every field has a dedicated inverted index for fast retrieval. And, unlike most other databases, it can use all of those inverted indices...
Ready to download the document? Go ahead and hit continue!