Infrastructure

Assessing URET Benefits for Airspace Users: A Quasi-Experimental Approach

Bolic, Tatjana
Mark Hansen
2002

Air traffic control organizations around the world are trying to develop automation tools to help controllers manage increasing workload and to enable user preferred routes. This paper focuses on such a tool: User Request Evaluation Tool (URET), which is a decision-support tool for en-route controllers. URET is a prototype of an automated conflict probe. Based on flight plans and actual radar tracks, the URET system models aircraft trajectories and predicts possible conflicts. It also enables controllers to check clearances for conflicts prior to their issuance. This tool is intended as a...

Airport Road Access at Planet Scale using Population Grid and Openstreetmap

Sun, Xiaoqian
Wandelt, Sebastian
Mark Hansen
2020

A new comparative framework for estimating the road access of airports around the world at high resolution is proposed. While existing studies are spatially constrained and often require hand-collection of data, this framework relies on freely available datasets at planet scale: Population density database Gridded Population of the World and transportation infrastructure database Openstreetmap. Access profiles from the airport-centric view (how many passengers are close to a fixed airport) and the population-centric view (how many airports are close to certain grid cells) are presented as...

USE-LFA: A Data-Driven Framework for UAM Site Evaluation using Latent Factor Analysis

Sohn, Sungmin
Kim, Namwoo
Mark Hansen
Yoon, Yoonjin
2025

Urban air mobility (UAM) introduces new challenges for infrastructure planning, requiring data driven approaches for sustainable site selection. This study proposes USE-LFA (Urban Site Evaluation using Latent Factor Analysis), a framework designed to support equitable and environmentally conscious siting of urban ports. Applying latent factor analysis to 25 urban attributes in Seoul, the framework identifies six latent factors, grouped into two dimensions: Suitability and Attractiveness. These dimensions are combined through a tunable prioritization metric, enabling alignment with local...

Pilot Models for Estimating Bicycle Intersection Volumes

Julia Griswold
Medury, Aditya
Schneider, Robert J.
2011

Bicycle volume data are useful to practitioners and researchers to understand safety, travel behavior, and development impacts. This paper describes the methodology used to develop several simple models of bicycle intersection volumes in Alameda County, California. The models are based on two-hour bicycle counts performed at a sample of 81 intersections in the Spring of 2008 and 2009. Study sites represented areas with a wide range of population density, employment density, proximity to commercial property, neighborhood income, and street network characteristics. The explanatory variables...

National Pedestrian and Bicycle Safety Data Clearinghouse Phase I: Inventory & Framework

Nordback, Krista
Kumfer, Wesley
LaJeunesse, Seth
Thomas, Libby
Heuser, Katie
Julia Griswold
University of North Carolina at Chapel Hill. Highway Safety Research Center
University of California, Berkeley
2019

Safety researchers, especially those studying bicycle and pedestrian safety, often struggle to obtain sufficiently high-quality data to conduct robust safety studies. The goal of the project is to create an online centralized data clearinghouse for bicycle and pedestrian safety-related data as a national resource for safety researchers to expedite research on this topic. CSCRS Project R14, the first phase of this work, produced a pilot online pedestrian and bicycle safety data resource clearinghouse available at pedbikedata.org. It allows researchers to search from over 4,000 pedestrian...

Creating an Inclusive Bicycle Level of Service: Virtual Bicycle Simulator Study

Julia Griswold
Aguilar, Edna
Wang, Han
Miah, Md Mintu
2025

Bicycle level of service (BLOS) is an essential performance measure for transportation agencies to monitor and prioritize improvements to infrastructure, but existing measures do not capture the nuance of facility differences on the state highway system. However, with the advancements in virtual reality (VR) technology, a VR bicycle simulator is an ideal tool to safely gather user feedback on a variety of bicycling environments and conditions. This research explored the benefits and limitations of using a VR environment to assess individuals’ bike infrastructure preferences. We conducted a...

Planning for Electric Vehicles Coupled with Urban Mobility

Xu, Yanyan
Çolak, Serdar
Kara, Emre C.
Scott Moura
Marta Gonzalez
2018

The rising adoption of plug-in electric vehicles (PEVs) leads to the alignment of their electricity and their mobility demands. Therefore, transportation and power infrastructures are becoming increasingly interdependent. In this work, we uncover patterns of PEV mobility by integrating for the first time two unique data sets: (i) mobile phone activity of 1.39 million Bay Area residents and (ii) charging activity of PEVs in 580,000 sessions obtained in the same region. We present a method to estimate individual mobility of PEV drivers at fine temporal and spatial resolution integrating...

Coupling Natural Hazard Estimates with Road Network Analysis to Assess Vulnerability and Risk: Case Study of Freetown (Sierra Leone)

Nelson, Andrew
Lindbergh, Sarah
Stephenson, Lucy
Halpern, Jeremy
Arroyo, Fatima Arroyo
Espinet, Xavier
Marta Gonzalez
2019

Many of the world’s most disaster-prone cities are also the most difficult to model and plan. Their high vulnerability to natural hazards is often defined by low levels of economic resources, data scarcity, and limited professional expertise. As the frequency and severity of natural disasters threaten to increase with climate change, and as cities sprawl and densify in hazardous areas, better decision-making tools are needed to mitigate the effects of near- and long-term extreme events. We use mostly public data from landslide and flooding events in 2017 in Freetown, Sierra Leone to...

A Data Science Framework for Planning the Growth of Bicycle Infrastructures

Olmos, Luis E.
Tadeo, Maria Sol
Vlachogiannis, Dimitris
Alhasoun, Fahad
Espinet Alegre, Xavier
Ochoa, Catalina
Targa, Felipe
Marta Gonzalez
2020

Cities around the world are turning to non-motorized transport alternatives to help solve congestion and pollution issues. This paradigm shift demands on new infrastructure that serves and boosts local cycling rates. This creates the need for novel data sources, tools, and methods that allow us to identify and prioritize locations where to intervene via properly planned cycling infrastructure. Here, we define potential demand as the total trips of the population that could be supported by bicycle paths. To that end, we use information from a phone-based travel demand and the trip distance...

The Dark Side of the Earth: Benchmarking Lighting Access for All Cities on Earth and the CityNet dataset

Albert, Adrian
Strano, Emanuele
Kaur, Jasleen
Marta Gonzalez
2021

In this paper, we present an analysis of urban form, defined as the spatial distribution of macroeconomic quantities that characterize a city such as population, built environmentBuilt environment, and energy useEnergy use. In particular, we develop a framework to study the question of “mismatch” between the spatial distribution of lighting levels observed in a city (which was previously shown to be a proxy for energy access and wealth levels) and that city’s population density and built area distribution. This allows us to rank cities globally by their ability to, intuitively, “match...