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View article: Comparison at Scale of Traffic Signal Cycle Split Failure Identification from High-Resolution Controller and Connected Vehicle Trajectory Data
Comparison at Scale of Traffic Signal Cycle Split Failure Identification from High-Resolution Controller and Connected Vehicle Trajectory Data Open
Split failures have been a conventional method to estimate overcapacity at signalized intersections. Currently, split failures are estimated from high-resolution (HR) traffic signal controller event data by evaluating occupancy at the stop…
View article: Applications of using connected vehicle data for pavement quality analysis
Applications of using connected vehicle data for pavement quality analysis Open
Current quantitative methods to evaluate pavement conditions in the United States are most commonly focused on construction acceptance using the International Roughness Index (IRI). However, from an asset management perspective, qualitativ…
View article: Development of Latitude/Longitude (and Route/Milepost) Model for Positioning Traffic Management Cameras
Development of Latitude/Longitude (and Route/Milepost) Model for Positioning Traffic Management Cameras Open
Traffic Incident Management (TIM) is a FHWA Every Day Counts initiative with the objective of reducing secondary crashes, improving travel reliability, and ensuring the safety of responders. Agency roadside cameras play a critical role in …
View article: Analysis of Connected Vehicle Data to Quantify National Mobility Impacts of Winter Storms for Decision Makers and Media Reports
Analysis of Connected Vehicle Data to Quantify National Mobility Impacts of Winter Storms for Decision Makers and Media Reports Open
Traditional techniques of monitoring roadway mobility during winter weather have relied on embedded road sensors, roadside cameras, radio reports from public safety staff, or public incident reports. However, widely available connected veh…
View article: Methodology for the Identification of Shock Wave Type and Speed in a Traffic Stream Using Connected Vehicle Data
Methodology for the Identification of Shock Wave Type and Speed in a Traffic Stream Using Connected Vehicle Data Open
The concept of traffic shock waves was first theorized by Lighthill and Whitham in 1955. The identification of shock wave type and speed in a traffic stream provides critical information about the queue formation and its dissipation. This …
View article: Using Connected Vehicle Data to Evaluate National Trip Trends
Using Connected Vehicle Data to Evaluate National Trip Trends Open
The National Household Travel Survey (NHTS), conducted by the Federal Highway Administration, has historically been used for documenting personal mobility trends. Current techniques using surveys to collect this data are labor-intensive an…
View article: Impact of Rain Intensity on Interstate Traffic Speeds Using Connected Vehicle Data
Impact of Rain Intensity on Interstate Traffic Speeds Using Connected Vehicle Data Open
With the emergence of connected vehicle data and high-resolution weather data, there is an opportunity to develop models with high spatial-temporal fidelity to characterize the impact of weather on interstate traffic speeds. In this study,…
View article: Trajectory-Based Arterial Traffic Signal Performance Measures Reports
Trajectory-Based Arterial Traffic Signal Performance Measures Reports Open
Traffic signal performance measures based on connected vehicle (CV) trajectory data can provide practitioners actionable information on the operational state of their systems. A visualization framework that can enable agencies to quickly a…
View article: National Mobility Analysis for All Interstate Routes in the United States
National Mobility Analysis for All Interstate Routes in the United States Open
In November 2022, Wejo Data Services Inc. provided Purdue with a national data set comprised of approximately 470 billion connected vehicle records covering all 50 states for the month of August 2022. The goal of the evaluation data set wa…
View article: Implementation of Enhanced Probe Data (CANBUS) for Tactical Workzone and Winter Operations Management
Implementation of Enhanced Probe Data (CANBUS) for Tactical Workzone and Winter Operations Management Open
For over a decade, segment-based probe data has been extensively used by transportation stakeholders for monitoring mobility on Indiana roadways. However, enhanced probe data from connected vehicles includes a richer dataset that can provi…
View article: Impacts to Traffic Behavior from Queue Warning Truck: Current Pilot Project
Impacts to Traffic Behavior from Queue Warning Truck: Current Pilot Project Open
The Indiana Department of Transportation (INDOT) started deploying queue warning trucks ahead of interstate work zones to alert motorists of queued traffic. Along with visually alerting the motorists, digital alerts were integrated with na…
View article: National Mobility Report for All Interstates–December 2022
National Mobility Report for All Interstates–December 2022 Open
In January 2023, Wejo Data Services Inc. provided Purdue with a national data set comprised of approximately 503 billion connected vehicle records covering all 50 states for the month of December 2022. The goal of the evaluation data set w…
View article: Reporting Framework for Arterial-Level Traffic Signal Performance Measures Estimated from Connected Vehicle Trajectory Data
Reporting Framework for Arterial-Level Traffic Signal Performance Measures Estimated from Connected Vehicle Trajectory Data Open
Traffic signal performance measures based on connected vehicle (CV) trajectory data can provide practitioners actionable information on the operational state of their systems. Agencies need visualization tools that can enable them to quick…
View article: Indiana Interstate Speed Profiles 2018–2022
Indiana Interstate Speed Profiles 2018–2022 Open
Systemwide interstate performance measures that detail hours and location of congestion on an interstate provide important information for decision makers to plan capital projects and assess operations. This report presents summary of mile…
View article: Next Generation Traffic Signal Performance Measures: Leveraging Connected Vehicle Data
Next Generation Traffic Signal Performance Measures: Leveraging Connected Vehicle Data Open
High-resolution connected vehicle (CV) trajectory and event data has recently become commercially available. With over 500 billion vehicle position records generated each month in the United States, these data sets provide unique opportuni…
View article: Correlating Connected Vehicle Estimated Deceleration Events with Crash Incidents near Interstate Interchanges
Correlating Connected Vehicle Estimated Deceleration Events with Crash Incidents near Interstate Interchanges Open
Historical roadway safety analyses have used labor and time-intensive crash data collection procedures. However, crash reporting is often delayed and crash locations are reported with varying levels of spatial accuracy and detail. Recent a…
View article: Crowdsourcing/Winter Operations Dashboard Upgrade
Crowdsourcing/Winter Operations Dashboard Upgrade Open
INDOT has recently completed the deployment of Parsons telematics-based dash-cameras, automatic vehicle locator (AVL) positions, and spreader rate monitoring across their winter operations fleet. The motivation of this study was to develop…
View article: Connected Vehicle-Centric Dashboards for TMC of the Future
Connected Vehicle-Centric Dashboards for TMC of the Future Open
The adoption of dashboards and tools into Traffic Management Centers (TMC) has been growing with advancements in connected vehicle (CV) data. These tools are now being utilized—not only for analyzing work zones, severe crashes, winter oper…
View article: Pavement Quality Evaluation Using Connected Vehicle Data
Pavement Quality Evaluation Using Connected Vehicle Data Open
Modern vehicles have extensive instrumentation that can be used to actively assess the condition of infrastructure such as pavement markings, signs, and pavement smoothness. Currently, pavement condition evaluations are performed by state …
View article: Measuring Roadway Lane Widths Using Connected Vehicle Sensor Data
Measuring Roadway Lane Widths Using Connected Vehicle Sensor Data Open
The United States has over three trillion vehicle miles of travel annually on over four million miles of public roadways, which require regular maintenance. To maintain and improve these facilities, agencies often temporarily close lanes, …
View article: Leveraging Connected Vehicle Data to Assess Interstate Exit Utilization and Identify Charging Infrastructure Investment Allocation Opportunities
Leveraging Connected Vehicle Data to Assess Interstate Exit Utilization and Identify Charging Infrastructure Investment Allocation Opportunities Open
With an influx of public and private sector investment in the electric vehicle (EV) domain, public agencies and stakeholders need objective, equitable and systematic processes for identifying candidate sites for siting charging stations. T…
View article: Methodology for Monitoring Work Zones Traffic Operations Using Connected Vehicle Data
Methodology for Monitoring Work Zones Traffic Operations Using Connected Vehicle Data Open
The National Work Zone Safety Information Clearinghouse estimated there were approximately 115,000 work zone crashes with 842 fatalities in 2019. There is broad consensus that it is important for agencies to develop near real-time risk ass…
View article: Using Connected Vehicle Trajectory Data to Evaluate the Impact of Automated Work Zone Speed Enforcement
Using Connected Vehicle Trajectory Data to Evaluate the Impact of Automated Work Zone Speed Enforcement Open
Work zone safety is a high priority for transportation agencies across the United States. Enforcing speed compliance in work zones is an important factor for reducing the frequency and severity of crashes. This paper uses connected vehicle…
View article: Continuous Flow Intersection Performance Measures Using Connected Vehicle Data
Continuous Flow Intersection Performance Measures Using Connected Vehicle Data Open
Continuous flow intersections (CFIs), also known as displaced left turns (DLTs), are a type of alternative intersection designed to improve operations at locations with heavy left-turn movements by reallocating these vehicles to the left s…
View article: Integration of Probe Data Tools into TMC Operations
Integration of Probe Data Tools into TMC Operations Open
With the advent of probe data, there is a need to virtualize many of the Traffic Management Center (TMC) tools used for analyzing work zones, severe crashes, winter operations, moving maintenance operations, and providing dashboards charac…
View article: Integrated Performance Measures for Bus Rapid Transit System and Traffic Signal Systems Using Trajectory Data
Integrated Performance Measures for Bus Rapid Transit System and Traffic Signal Systems Using Trajectory Data Open
Bus rapid transit (BRT) systems have been implemented in many cities over the past two decades. Widespread adoption of General Transit Feed Specification (GTFS), the deployment of high-fidelity bus GPS data tracking, and anonymized high-fi…
View article: Diamond Interchange Performance Measures Using Connected Vehicle Data
Diamond Interchange Performance Measures Using Connected Vehicle Data Open
Diamond interchanges are frequently used where a freeway intersects a two-way surface street. Most of the techniques to evaluate the performance of diamond interchanges rely on the Highway Capacity Manual (HCM), simulation, Automated Traff…
View article: Observations of Trip Generation, Route Choice, and Trip Chaining with Private-Sector Probe Vehicle GPS Data
Observations of Trip Generation, Route Choice, and Trip Chaining with Private-Sector Probe Vehicle GPS Data Open
This paper presents an exploratory study of GPS data from a private-sector data provider for analysis of trip generation, route choice, and trip chaining. The study focuses on travel to and from the Indianapolis International Airport. GPS …
View article: Calibration and Confidence in Snowplow Fleet Operations and Fleet Telematics
Calibration and Confidence in Snowplow Fleet Operations and Fleet Telematics Open
The Indiana Department of Transportation (INDOT) spends approximately $30 to $60 million a year on deicing salt and operates a fleet of 1,000 winter operations trucks distributed among 140 locations. The entire fleet is now instrumented wi…
View article: Analysis of Route Choice During Planned and Unplanned Road Closures
Analysis of Route Choice During Planned and Unplanned Road Closures Open
The Federal Highway Administration (FHWA) Alternate Route Handbook proposes guidance to identify alternate routes during planned and unplanned road closures. A challenge with this process is the lack of traffic data available to decision-m…