Publications

Summary:
We utilize an unsupervised learning algorithm called-modes clustering (Huang 1998), which is similar to the better-known-means method (Hartigan and Wong 1979), but with a dissimilarity measure designed for categorical variables (Cao et al. 2012), originally developed for analyzing sequential categorical data such as gene sequences (Goodall 1966), but also amenable to curb zoning types.

Summary:
The Seattle Department of Transportation (SDOT) partnered with the University of Washington to explore how commercial vehicle parking in Seattle’s downtown area affects the safety of bicyclists. The hypothesis was that increased truck access to SDOT’s commercial vehicle loading zones (CVLZs) can positively contribute to bicycle safety.

Summary:
This report examines pedestrian and motorist behavior on arterials in Washington State and determines how, if at all, these behaviors change when various engineering treatments are applied. The treatments that were examined included crosswalk markings, raised medians, in-pavement flashers, signage, stop bars, overhead lighting, and sidewalks. The relationships between pedestrian travel and transit use, origin-destination patterns, traffic signals, and schools were also explored.

Summary:
This paper evaluates whether or not there is a sprawling tendency to the spatial patterns of warehouse establishments in the Chicago and Phoenix metropolitan areas. The trend of warehouses to move away from the urban centers to more suburban and exurban areas is referred to as “Logistics Sprawl”.

Summary:
There is little research on the behavioral interaction between bicycle lanes and commercial vehicle loading zones (CVLZ) in the United States. These interactions are important to understand, to preempt increasing conflicts between truckers and bicyclists. In this study, a bicycling simulator experiment examined bicycle and truck interactions. The experiment was successfully completed by 48 participants.

Summary:
Intra-industry trade (IIT) occurs when trading partners import and export similar products. A high volume of IIT of horizontally differentiated goods implies a deep level of regional integration, stable regional trading patterns, and potentially significant consequences from border delay. In this paper, trade between Washington State and British Columbia, Canada (the Cascade gateway), is compared with trade between Michigan State and Ontario, Canada (the Great Lakes gateway).

Summary:
The purpose of this research is to explore consumers’ online shopping and in-person shopping travel behaviors and the factors affecting these behaviors within the geographical context of the study area of West Seattle. West Seattle is a peninsula located southwest of downtown Seattle, Washington State. In March 2020, the West Seattle High Bridge, the main bridge connecting the peninsula to the rest of the city, was closed to traffic due to its increased rate of structural deterioration.

Summary:
Ridehailing services (e.g., Uber or Lyft) may serve as a substitute or a complement—or some combination thereof—to transit. Automation as an emerging technology is expected to further complicate the current complex relationship between transit and ridehailing. This paper aims to explore how US commuters’ stated willingness to ride transit is influenced by the price of ridehailing services and whether the service is provided by an autonomous vehicle.

Summary:
The rapid spread of COVID-19 pandemic in the U.S. spurred many state governments to take extensive actions for social distancing and issue stay-at-home orders to reduce the spread of the virus. Washington State and all other States in the PacTrans region have issued stay-at-home orders that include school closures, telecommuting, bars/restaurants closures, and group gathering bans, among others.

Summary:
It is generally accepted that automation as an emerging technology in transportation sector could have a potential huge effect on changing the way individuals travel. In this study, the impact of automation technology on the market share of current transportation modes has been examined. A stated preference (SP) survey was launched around the U.S. to ask 1500 commuters how they would choose their commute mode if they had the option to choose between their current mode and an autonomous mode....

Summary:
Two converging trends – the rise of e‐commerce and urban population growth – challenge cities facing competing uses for road, curb and alley space. The University of Washington has formed a living Urban Freight Lab to solve city logistics problems that cross private and public sector boundaries.

Summary:
The safety effects of cooperative intelligent transport systems (C-ITS) are mostly unknown and associated with uncertainties, because these systems represent emerging technology. This study proposes a bowtie analysis as a conceptual framework for evaluating the safety effect of cooperative intelligent transport systems. These seek to prevent road traffic accidents or mitigate their consequences.

Summary:
Decisions to install public bike-share programs are increasingly based on ridership estimations, but the topography’s influence on ridership is rarely quantified. This research evaluated a geographic information system-based approach for estimating ridership that accounted for hills. Double-weighting a slope relative to other measures produces a realistic representation of the bicycling experience.

Summary:
The distribution of goods and services in North American cities has conventionally relied on diesel-powered internal combustion engine (ICE) vehicles. Recent developments in electromobility have provided an opportunity to reduce some of the negative externalities generated by urban logistics systems. Cargo e-bikes — electric cycles specially designed for cargo transportation — represent an alternative environmentally friendly and safer mode for delivering goods and services in urban areas.

Summary:
Estimating the safety effects of emerging or future technology based on expert acquisitions is challenging because the accumulated judgment is at risk of being biased and imprecise. Therefore, this semiquantitative study proposes and demonstrates an upgraded bowtie analysis for safety effect assessments that can be performed without the need for expert acquisition. While bowtie analysis is commonly used in, for example, process engineering, it is novel in road traffic safety.