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Paper

A Meta-Heuristic Solution Approach to Isolated Evacuation Problems

 
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Publication: IEEE (Institute of Electrical and Electronics Engineers)
Volume: 2022 Winter Simulation Conference (WSC) INFORMS
Publication Date: 2022
Summary:

This paper provides an approximation method for the optimization of isolated evacuation operations, modeled through the recently introduced Isolated Community Evacuation Problem (ICEP). This routing model optimizes the planning for evacuations of isolated areas, such as islands, mountain valleys, or locations cut off through hostile military action or other hazards that are not accessible by road and require evacuation by a coordinated set of special equipment. Due to its routing structure, the ICEP is NP-complete and does not scale well. The urgent need for decisions during emergencies requires evacuation models to be solved quickly. Therefore, this paper investigates solving this problem using a Biased Random-Key Genetic Algorithm. The paper presents a new decoder specific to the ICEP, that allows to translate in between an instance of the S-ICEP and the BRKGA. This method approximates the global optimum and is suitable for parallel processing. The method is validated through computational experiments.

Authors: Dr. Anne GoodchildFiete Krutein, Linda Ng Boyle (University of Washington Dept. of Industrial & Systems Engineering)
Recommended Citation:
K. F. Krutein, L. N. Boyle and A. Goodchild, "A Meta-Heuristic Solution Approach to Isolated Evacuation Problems," 2022 Winter Simulation Conference (WSC), Singapore, 2022, pp. 2002-2012, doi: 10.1109/WSC57314.2022.10015470.
Paper

Commercial Vehicle Driver Behaviors and Decision Making: Lessons Learned from Urban Ridealongs

 
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Publication:  Transportation Research Record: Journal of the Transportation Research Board
Volume: 2675 (9)
Pages: 608-619
Publication Date: 2021
Summary:

As ecommerce and urban deliveries spike, cities grapple with managing urban freight more actively. To manage urban deliveries effectively, city planners and policy makers need to better understand driver behaviors and the challenges they experience in making deliveries.

In this study, we collected data on commercial vehicle (CV) driver behaviors by performing ridealongs with various logistics carriers. Ridealongs were performed in Seattle, Washington, covering a range of vehicles (cars, vans, and trucks), goods (parcels, mail, beverages, and printed materials), and customer types (residential, office, large and small retail). Observers collected qualitative observations and quantitative data on trip and dwell times, while also tracking vehicles with global positioning system devices.

The results showed that, on average, urban CVs spent 80% of their daily operating time parked. The study also found that, unlike the common belief, drivers (especially those operating heavier vehicles) parked in authorized parking locations, with only less than 5% of stops occurring in the travel lane. Dwell times associated with authorized parking locations were significantly longer than those of other parking locations, and mail and heavy goods deliveries generally had longer dwell times.

We also identified three main criteria CV drivers used for choosing a parking location: avoiding unsafe maneuvers, minimizing conflicts with other users of the road, and competition with other commercial drivers.

The results provide estimates for trip times, dwell times, and parking choice types, as well as insights into why those decisions are made and the factors affecting driver choices.

In recent years, cities have changed their approach toward managing urban freight vehicles. Passive regulations, such as limiting delivery vehicles’ road and curb use to given time windows or areas have been replaced by active management through designing policies for deploying more commercial vehicle (CV) load zones, pay-per-use load zone pricing, curb reservations, and parking information systems. The goal is to reduce the negative externalities produced by urban freight vehicles, such as noise and emissions, traffic congestion, and unauthorized parking, while guaranteeing goods flow in dense urban areas. To accomplish this goal, planners need to have an understanding of the fundamental parking decision-making process and behaviors of CV drivers.

Two main difficulties are encountered when CV driver behaviors are analyzed. First, freight movement in urban areas is a very heterogeneous phenomenon. Drivers face numerous challenges and have to adopt different travel and parking behaviors to navigate the complex urban network and perform deliveries and pick-ups. Therefore, researchers and policy makers find it harder to identify common behaviors and responses to policy actions for freight vehicles than for passenger vehicles. Second, there is a lack of available data. Most data on CV movements are collected by private carriers, who use them to make business decisions and therefore rarely release them to the public. Lack of data results in a lack of fundamental knowledge of the urban freight system, inhibiting policy makers’ ability to make data-driven decisions.

The urban freight literature discusses research that has employed various data collection techniques to study CV driver behaviors. Cherrett et al. reviewed 30 UK surveys on urban delivery activity and performed empirical analyses on delivery rates, time-of-day choice, types of vehicles used to perform deliveries, and dwell time distribution, among others. The surveys reviewed were mostly establishment-based, capturing driver behaviors at specific locations and times of the day. Allen et al. performed a more comprehensive investigation, reviewing different survey techniques used to study urban freight activities, including driver surveys, field observations, vehicle trip diaries, and global positioning system (GPS) traces. Driver surveys collect data on driver activities and are usually performed through in-person interviews with drivers outside their working hours or at roadside at specific locations. In-person interviews provide valuable insights into driver choices and decisions but are often limited by the locations at which the interviews occur or might not reflect actual choices because they are done outside the driver work context. Vehicle trip diaries involve drivers recording their daily activities while field observations entail observing driver activities at specific locations and establishments; neither collects insights into the challenges that drivers face during their trips and how they make certain decisions. The same limitations hold true for data collected through GPS traces. Allen et al. mentioned the collection of travel diaries by surveyors traveling in vehicles with drivers performing deliveries and pick-ups as another data collection technique that could provide useful insights into how deliveries/pick-ups are performed. However, they acknowledged that collecting this type of data is cumbersome because of the difficulty of obtaining permission from carriers and the large effort needed to coordinate data collection.

This study aims to fill that gap by collecting data on driver decision-making behaviors through observations made while riding along with CV drivers. A systematic approach was taken to observe and collect data on last-mile deliveries, combining both qualitative observations and quantitative data from GPS traces. The ridealongs were performed with various delivery companies in Seattle, Washington, covering a range of vehicle types (cars, vans, and trucks), goods types (parcels, mail, beverages, and printed materials), and customer types (residential, office, large and small retail).

The data collected will not only add to the existing literature by providing estimates of trip times, parking choice types, time and distance spent cruising for parking, and parking dwell times but will also provide insights into why those decisions are made and the factors affecting driver choices.

The objectives of this study are to provide a better understanding of CV driver behaviors and to identify common and unique challenges they experience in performing the last mile. These findings will help city planners, policy makers, and delivery companies work together better to address those challenges and improve urban delivery efficiency.

The next section of this paper describes the relevant literature on empirical urban freight behavior studies. The following section then introduces the ridealongs performed and the data collection methods employed. Next, analysis of the data and qualitative observations from the ridealongs are described, and the results are discussed in five overarching categories: the time spent in and out of the vehicle, parking location choice, the reasons behind those choices, parking cruising time, and factors affecting dwell time.

Recommended Citation:
Chiara, Giacomo Dalla, Krutein, Klaas Fiete, Ranjbari, Andisheh, & Goodchild, Anne. (2021). Understanding Urban Commercial Vehicle Driver Behaviors and Decision Making. Transportation Research Record, 2675(9), 608-619. https://doi.org/10.1177/03611981211003575
Paper

Empirical Analysis of Relieving High-Speed Rail Freight Congestion in China

 
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Publication: Sustainability
Volume: 12(23)
Publication Date: 2020
Summary:

This paper discusses how to promote high-speed rail (HSR) freight business by solving the congestion problem. First, we define the existing operation modes in China and propose the idea of relieving congestion by reserving more carriages of HSR passenger trains for freight between cities with large potential volume or small capacity. Second, we take one HSR corridor as a case to study, and use predictive regression and integrated time series methods to forecast the growth of HSR freight volume along the corridor. Finally, combined with forecast results and available capacity during the peak month of 2018, we offer suggestions on the mode adoption in each segment during the peak month from 2019 to 2022. Results demonstrate: (1) Among all 84 Origin-Destination (OD) city flows, the percentage of those monthly volumes over 1 ton increases from 17.9% in 2018 to 84.6% in 2022, and those over 30 tons rise from 3.6% to 26.2%. (2) Among the segments between seven main cities in the HSR corridor, T-J should be given priority to operate trains with reserved mode; the segment between X and J deserves to reserve most carriages during the peak month in the future. Specifically, our model suggests reserving 5.3–10.1 carriages/day for J-X, and 4.8–16.3 carriages/day for X-J during the peak month from 2019 to 2022.

Authors: Hanlin GaoDr. Anne Goodchild, Meiqing Zhang
Recommended Citation:
Hanlin Gao, Meiqing Zhang, & Anne Goodchild. (2020). Empirical Analysis of Relieving High-Speed Rail Freight Congestion in China. Sustainability (Basel, Switzerland), 12(23). https://doi.org/10.3390/su12239918 
Paper

Bowtie Analysis without Expert Acquisition for Safety Effect Assessments of Cooperative Intelligent Transport Systems

 
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Publication: ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering
Publication Date: 2018
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. Four crash case studies are completed using bowtie analysis, letting the input parameters sequentially vary over the entire range of possible expert opinions. The results suggest that only proactive safety measures estimated to decrease the probability of specific crash risk factors to at least “very improbable” can perceptibly decrease crash probability. Further, the success probability of a reactive measure must be at least “moderately probable” to reduce the probability of a serious or fatal crash by half or more. This upgraded bowtie approach allows the identification of (1) the sensitivity of the probability of a crash and its consequences to expert judgment used in the bowtie model and (2) the necessary effectiveness of a chosen safety measure allowing adequate changes in the probability of a crash and its consequences.

 

 

Authors: Dr. Ed McCormack, Ute Christine Ehlers; Eirin Olaussen Ryengm Faisal Khan, and Sören Ehlers
Recommended Citation:
Ehlers, U. C., Ryeng, E. O., McCormack, E., Khan, F., & Ehlers, S. (2018). Bowtie Analysis without Expert Acquisition for Safety Effect Assessments of Cooperative Intelligent Transport Systems. ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering, 4(4), 04018036.
Paper

The Effect of Distance on Cargo Flows: A Case Study of Chinese Imports and Their Hinterland Destinations

 
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Publication: Maritime Economics & Logistics
Volume: 20
Pages: 456-475
Publication Date: 2018
Summary:

 

With the rapid development of ports in China, competition for cargo is growing. The ability of a port to attract hinterland traffic is affected by many factors, including distance to the hinterland destinations. This paper studies the effects of distance on import cargo flows from a port to its hinterland. Two major findings are reported. Through a Spatial Concentration Analysis, this study shows that cargo imported through ports with relatively low throughput is primarily delivered to local areas, with the proportion of cargo delivered to local areas from larger ports being much smaller. The present study also shows (according to a gravity model, the Gompertz function and several other methods) that cargo flows from a large port to its hinterland increase with distance below a certain threshold, while cargo flows approach a stable state once they exceed this threshold. These results can be used to inform port managers and policy makers regarding the hinterland markets for ports of different sizes.

Authors: Dr. Anne Goodchild, Likun Wang, Yong Wang
Recommended Citation:
Wang, Likun, Anne Goodchild, and Yong Wang. (2017) The Effect of Distance on Cargo Flows: A Case Study of Chinese Imports and Their Hinterland Destinations. Maritime Economics & Logistics, 20(3), 456–475. https://doi.org/10.1057/s41278-017-0079-3
Paper

Effect of Tsunami Damage on Passenger and Forestry Transportation in Pacific County Washington

 
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Publication: Transportation Research Record: Journal of the Transportation Research Board
Volume: 2604 (1)
Pages: 88-94
Publication Date: 2017
Summary:

The outer coast of Washington State is exposed to significant seismic and tsunami hazards. A Cascadia Subduction Zone (CSZ) event is expected to cause high earthquake intensities and tsunami inundation resulting in considerable infrastructure loss, inundation of developed land, and degraded functioning of coastal communities.

One area of particular concern is Pacific County, located in southwest Washington, where over 85% of the population is expected to experience severe shaking intensities.

This paper establishes the pre-disaster passenger and freight transportation patterns and the damaged post-disaster road network in Pacific County. The hazard used in the analysis is the CSZ magnitude 9.1 earthquake and resulting tsunami. Passenger travel is compared to forestry travel along the following characteristics: overall change in travel distance, percentage of trips that are longer, the percentage of trips that are no longer possible, and the distributions of travel distance.

Because passenger and freight travel have different purposes and patterns, understanding how they are affected differently can serve as a foundation for community-based disaster recovery planning to increase community resilience to earthquakes and tsunamis.

Authors: Dr. Anne Goodchild, Maura Rowell
Recommended Citation:
Rowell, Maura, and Anne Goodchild. "Effect of Tsunami Damage on Passenger and Forestry Transportation in Pacific County, Washington." Transportation Research Record 2604, no. 1 (2017): 88-94.
Paper

Logistics Sprawl: Differential Warehousing Development Patterns in Los Angeles and Seattle

 
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Publication: Transportation Research Record: Journal of the Transportation Research Board
Volume: 2410
Pages: 105-112
Publication Date: 2014
Summary:

The warehousing industry experienced a period of rapid growth from 1998 to 2009. This paper compares how the geographic distribution of warehouses changed in both the Los Angeles and Seattle Metropolitan Areas over that time period. These two west coast cities were chosen due to their geographic spread and proximity to major ports as well as their difference in size. The phenomenon of logistics sprawl, or the movement of logistics facilities away from urban centers, which has been demonstrated in past research for the Atlanta and Paris regions, is examined for these two areas. The weighted geometric center of warehousing establishments was calculated for both areas for both years, along with the change in the average distance of warehouses to that center, an indicator of sprawl. We find that between 1998 and 2009, warehousing in Los Angeles sprawled considerably, with the average distance increasing from 25.91 to 31.96 miles, an increase of over 6 miles. However in Seattle, the region remained relatively stable, showing a slight decrease in average distance from the geographic center. Possible explanations for this difference are discussed.

Authors: Dr. Anne Goodchild, Laetitia Dablanc, Scott Ogilvie
Recommended Citation:
Dablanc, Laetitia, Scott Ogilvie, and Anne Goodchild. "Logistics sprawl: differential warehousing development patterns in Los Angeles, California, and Seattle, Washington." Transportation Research Record 2410, no. 1 (2014): 105-112. 
Paper

Crane Double-Cycling in Container Ports: Planning Methods and Evaluation

 
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Publication: Transportation Research Part B: Methodological
Volume: 41(8)
Pages: 875-891
Publication Date: 2007
Summary:

The Clean Trucks Program is a Clean Air Action Plan initiative currently being adopted by the Ports of Los Angeles and Long Beach. This paper examines the Clean Trucks Program’s current requirements and estimates the impact on terminal operations. Using terminal operations data supplied by three terminal operating companies, we conduct a simple queuing analysis and present a regression model that allows us to consider the potential impact of the policy changes.

While this paper does not estimate the impact at a specific terminal, we consider order of magnitude effects. While the program itself does not require terminal operations changes, the program will modestly increase incentives to improve operational efficiency outside the terminal and reduce terminal gate processing time. It will also require technology that could be used for further operational changes.

We show, however, that unless gate time improvements are matched with these operational improvements in the terminal, they will only move the delay inside the terminal and not reduce total terminal time.

Our research considers the impact of the Clean Trucks Program on the Ports of Los Angeles and Long Beach, but similar concerns are driving changes at ports around the globe.

Authors: Dr. Anne Goodchild, C.F. Daganzo
Recommended Citation:
Goodchild, A.V., and C.F. Daganzo. “Crane Double Cycling in Container Ports: Planning Methods and Evaluation.” Transportation Research Part B: Methodological, vol. 41, no. 8, 2007, pp. 875–891., doi:10.1016/j.trb.2007.02.006.