Traffic Operations and Management

Intersection Decision Support Project: Taxonomy of Crossing-Path Crashes at Intersections Using GES 2000 Data

Ragland, David R.
Zabyshny, Aleksandr A.
2003

The Intersection Decision Support (IDS) Project is designed to reduce crossing-path (CP) crashes at intersections by providing crucial information to drivers that would help them avoid such crashes. Over the past decade, researchers have used the General Estimates System (GES, a representative sample of police-reported crashes in the US) and other data sources to develop a taxonomy of CP crashes and pre-crash scenarios as groundwork for crash-prevention efforts. The current study builds on and extends prior work by constructing a taxonomy of CP crashes using data from the 2000 GES and...

Safety and Other Impacts of Vehicle Impound Enforcement

Cooper, Douglas
Chira-Chavala, T.
Gillen, David
2002

California vehicle impound law took affect on January 1, 1995. The law allows a police officer to seize a vehicle operated by a person whose license is suspended or revoked or who has never been issued a license. The seized vehicle shall then be impounded for 30 days. In California, a driver must be stopped for some other infraction before his/her license can be checked. The purpose of this evaluation is to assess the impact of Upland's vehicle impound program on traffic safety (crashes and on-the-road behavior) and police department resources and operations.

Cost-Effectiveness of Traffic Safety Interventions in the United States

Vahindnia, Farnaz, PhD
Walsh, Julia PhD
2002

In order to demonstrate the results of all available studies on cost-effectiveness and traffic safety, and report them in a comparable format, we conducted a comprehensive review of the literature on the subject. Knowledge of cost-effective (CE) traffic safety programs that result in reduced motor vehicle crashes and fatalities is essential to city planners, managers, and police. METHOD: Using a systematic approach to literature review, the relevant literature has been identified through the use of electronic databases, hand searching of journals, scanning reference lists, and consultation...

Experimental Evaluation of the Continuous Risk Profile (CRP) Approach to the Current Caltrans Methodology for High Collision Concentration Location Identification

Grembek, Offer
Kim, Kwangho
Kwon, Oh Hoon
Lee, Jinwoo
Liu, Haotian
Park, Min Ju
Washington, Simon
Ragland, David
Madanat, Samer M.
2012

This report evaluates the performance of Continuous Risk Profile (CRP) compared with the Sliding Window Method (SWM) and Peak Searching (PS) methods. These three network screening methods all require the same inputs: traffic collision data and Safety Performance Functions (SPFs), however, depending on how these input parameters are analyzed at the network screening level, the result of the analysis can vary significantly. Findings indicated that the CRP method produced far fewer false positives than SWM and PS. The false negative rates for CRP, SWM and PS were comparable. These findings...

Compliance, Congestion, and Social Equity: Tackling Critical Evacuation Challenges through the Sharing Economy, Joint Choice Modeling, and Regret Minimization

Wong, Stephen D.
2020

Evacuations are a primary transportation strategy to protect populations from natural and humanmade disasters. Recent evacuations, particularly from hurricanes and wildfires, have exposed three critical evacuation challenges: 1) persistent evacuation non-compliance to mandatory evacuation orders; 2) poor transportation response, leading to heavy congestion, slow evacuation clearance times, and high evacuee risk; and 3) minimal attention in ensuring all populations, especially those most vulnerable, have transportation and shelter. With ongoing climate change and increasing land development...

The Potential Societal Barriers of Urban Air Mobility (UAM)

Shaheen, Susan, PhD
Cohen, Adam
Farrar, Emily
2018

Urban Air Mobility (UAM) is an emerging concept of air transportation where small package delivery drones to passenger-carrying air taxis operate over populated areas, from small towns to the largest cities are being considered. This could revolutionize the way people move within and around cities by shortening commute times, bypassing ground congestion, and enabling point-to-point flights across cities. In recent years, several companies have designed and tested enabling elements of this concept, including; prototypes of Vertical Take-Off Landing (VTOL) capable vehicles, operational...

Developing Transportation Response Strategies for Wildfire Evacuations via an Empirically Supported Traffic Simulation of Berkeley, California

Zhao, Bingyu
Wong, Steven D.
2021

Government agencies must make rapid and informed decisions in wildfires to safely evacuate people. However, current evacuation simulation tools for resource-strapped agencies largely fail to compare possible transportation responses or incorporate empirical evidence from past wildfires. Consequently, we employ online survey data from evacuees of the 2017 Northern California Wildfires (n=37), the 2017 Southern California Wildfires (n=175), and the 2018 Carr Wildfire (n=254) to inform a policy-oriented traffic evacuation simulation model. We test our simulation for a hypothetical wildfire...

Fleeing from Hurricane Irma: Empirical Analysis of Evacuation Behavior Using Discrete Choice Theory

Wong, Steven D.
Pel, Adam J.
Shaheen, Susan A.
2020

This paper analyzes the observed decision-making behavior of a sample of individuals impacted by Hurricane Irmain2017(n = 645) by applying advanced methods based in discrete choice theory. Our first contribution is identifyingpopulation segments with distinct behavior by constructinga latent class choice model for the choice whether to evacuate or not. We find two latent segments distinguished by demographics and risk perception that tend to be either evacuation-keen or evacuation-reluctant and respond differently to mandatory evacuation orders.Evacuees subsequently face a multi-...

ITS Standards: A System Management Perspective

Intihar, Chris
Hall, Randolf
1997

This working paper is part of a larger project examining how the State of California should respond to the National System Architecture (NSA) for Intelligent Transportation Systems. The specific focus of this paper is on the role of standardization in managing and controlling the transportation system. The paper reviews activities and processes used by standards setting organization in transportation. We conclude that national and international standards will continue to address the needs for defining common interfaces...

Decision Support And Consensus Building For PLANiTS

Kanafani, Adib
Crotty, Melanie
1993

This paper describes the specifications and the determinants for inclusion of a deliberative process to support intelligent transportation planning. Specifications for a system suitable for transportation planning have been defined, as have the determinants of a prototype for inclusion in early versions of an intelligent transportation planning process. The PLANiTS ( Planning and Analysis to Integrate Intelligent Urban Transportation Systems) framework is utilized in this project.