Paper

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

URL: http://dx.doi.org/10.1061/AJRUA6.0000986

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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URL: https://doi.org/10.1057/s41278-017-0079-3

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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URL: https://doi.org/10.3141/2604-11

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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URL: https://doi.org/10.3141/2410-12

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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URL: https://doi.org/10.1016/j.trb.2007.02.006

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.

Paper

Do Parcel Lockers Reduce Delivery Times? Evidence from the Field

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URL: https://doi.org/10.1016/j.tre.2023.103070

Publication: Transportation Research Part E: Logistics and Transportation Review

Volume: 172 (2023)

Publication Date: 2023

Summary:

Common carrier parcel lockers have emerged as a secure, automated, self-service means of delivery consolidation in congested urban areas, which are believed to mitigate last-mile delivery challenges by reducing out-of-vehicle delivery times and consequently vehicle dwell times at the curb. However, little research exists to empirically demonstrate the environmental and efficiency gains from this technology. In this study, we designed a nonequivalent group pre-test/post-test control experiment to estimate the causal effects of a parcel locker on delivery times in a residential building in downtown Seattle. The causal effects are measured in terms of vehicle dwell time and the time delivery couriers spend inside the building, through the difference-in-difference method and using a similar nearby residential building as a control. The results showed a statistically significant decrease in time spent inside the building and a small yet insignificant reduction in delivery vehicle dwell time at the curb. The locker was also well received by the building managers and residents.

Authors: Dr. Andisheh RanjbariCaleb DiehlDr. Giacomo Dalla ChiaraDr. Anne Goodchild

Recommended Citation:
Ranjbari, A., Diehl, C., Dalla Chiara, G., & Goodchild, A. (2023). Do Commercial Vehicles Cruise for Parking? Empirical Evidence from Seattle. Transportation Research Part E: Logistics and Transportation Review, 172, 103070. https://doi.org/10.1016/j.tre.2023.103070

Paper

The Isolated Community Evacuation Problem with Mixed Integer Programming

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URL: https://doi.org/10.1016/j.tre.2022.102710

Publication: Transportation Research Part E: Logistics and Transportation Review

Volume: 161

Pages: 102710

Publication Date: 2022

Summary:

As awareness of the vulnerability of isolated regions to natural disasters grows, the demand for efficient evacuation plans is increasing. However, isolated areas, such as islands, often have characteristics that make conventional methods, such as evacuation by private vehicle, impractical to infeasible. Mathematical models are conventional tools for evacuation planning. Most previous models have focused on densely populated areas, and are inapplicable to isolated communities that are dependent on marine vessels or aircraft to evacuate. This paper introduces the Isolated Community Evacuation Problem (ICEP) and a corresponding mixed integer programming formulation that aims to minimize the evacuation time of an isolated community through optimally routing a coordinated fleet of heterogeneous recovery resources. ICEP differs from previous models on resource-based evacuation in that it is highly asymmetric and incorporates compatibility issues between resources and access points. The formulation is expanded to a two-stage stochastic problem that allows scenario-based optimal resource planning while also ensuring minimal evacuation time. In addition, objective functions with a varying degree of risk are provided, and the sensitivity of the model to different objective functions and problem sizes is presented through numerical experiments. To increase efficiency, structure-based heuristics to solve the deterministic and stochastic problems are introduced and evaluated through computational experiments. The results give researchers and emergency planners in remote areas a tool to build optimal evacuation plans given the heterogeneous resource fleets available, which is something they have not been previously able to do and to take actions to improve the resilience of their communities accordingly.

Authors: Fiete KruteinDr. Anne Goodchild

Recommended Citation:
Krutein, K. F., & Goodchild, A. (2022). The isolated community evacuation problem with mixed integer programming. In Transportation Research Part E: Logistics and Transportation Review (Vol. 161, p. 102710). Elsevier BV. https://doi.org/10.1016/j.tre.2022.10271

Paper

Testing Curbside Management Strategies to Mitigate the Impacts of Ridesourcing Services on Traffic

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URL: https://doi.org/10.1177%2F0361198120957314

Publication: Transportation Research Record: Journal of the Transportation Research Board

Publication Date: 2020

Summary:

Increased use of ridehailing leads to increased pick-up and drop-off activity. This may slow traffic or cause delays as vehicles increase curb use, conduct pick-up and drop-off activity directly in the travel lane, or slow to find and connect with passengers. How should cities respond to this change in an effort to keep travel lanes operating smoothly and efficiently? This research evaluates two strategies in Seattle, WA, in an area where large numbers of workers commute using ridesourcing services: (i) a change of curb allocation from paid parking to passenger load zone (PLZ), and (ii) a geofencing approach by transportation network companies (TNCs) which directs their drivers and passengers to designated pick-up and drop-off locations on a block. An array of data on street and curb activity along three study blockfaces was collected, using video and sensor technology as well as in-person observations. Data were collected in three phases: (i) the baseline, (ii) after the new PLZs were added, expanding total PLZ curb length from 20 ft to 274 ft, and (iii) after geofencing was added to the expanded PLZs. The added PLZs were open to any passenger vehicle (not just TNC vehicles), weekdays 7:00–10:00 a.m. and 2:00–7:00 p.m. The results showed that the increased PLZ allocation and geofencing strategy reduced the number of pick-ups/drop-offs in the travel lane, reduced dwell times, increased curb use compliance, and increased TNC passenger satisfaction. The two strategies, however, had no observable effect on travel speeds or traffic safety in the selected study area.

Authors: Dr. Anne GoodchildDr. Giacomo Dalla ChiaraDr. Andisheh RanjbariJosé Luis Machado León

Recommended Citation:
Ranjbari, Andisheh, Jose Luis Machado-León, Giacomo Dalla Chiara, Don MacKenzie, and Anne Goodchild. “Testing Curbside Management Strategies to Mitigate the Impacts of Ridesourcing Services on Traffic.” Transportation Research Record, (October 2020). https://doi.org/10.1177/0361198120957314.

Paper

Bike-Share Planning in Cities with Varied Terrain

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URL: https://search.proquest.com/docview/1547331247

Publication: Institute of Transportation Engineers (ITE) Journal

Volume: 84:07:00

Pages: 31-35

Publication Date: 2014

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. Because of their benefits, bike-share programs are increasingly of interest in cities and universities across the country. A bike-share program provides short-term use bicycles to the public through a system of unattended stations for their checkout and return. This research enhanced methodology developed in Philadelphia by developing and evaluating an additional indicator that accounts for hills. Several scenarios were tested, using Seattle as a case study, to find the best method to account for the notable impact of hills on bike riders’ choices and to evaluate the addition of slope to the calculation of bike-share demand.

Authors: Dr. Ed McCormack, Erica Wygonik, Daniel H. Rowe

Recommended Citation:
McCormack, E., & Rowe, D. H. (2014). Bike-share planning in cities with varied terrain. Institute of Transportation Engineers. ITE Journal, 84(7), 31.

Paper

An Evaluation of Logistics Sprawl in Chicago and Phoenix

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URL: https://doi.org/10.1016/j.jtrangeo.2018.08.008

Publication: Journal of Transport Geography

Volume: 88

Publication Date: 2018

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”. To measure sprawl, the barycenter of warehousing establishments was compared to the barycenter of all other industry establishments in the region between the years of 1998 and 2013 for Chicago; 1998 and 2015 for Phoenix. This shows that logistics sprawl is a behavior experienced by warehouses in the Chicago area, but not in the Phoenix area. This paper discusses if logistics sprawl is a national trend or a regional behavior by comparing these results to the previous case studies of the Atlanta, Los Angeles, and Seattle metropolitan areas.

Authors: Dr. Anne Goodchild, Melaku Dubie, Kai C. Kuo

Recommended Citation:
Dubie, Melaku, Kai C. Kuo, Gabriela Giron-Valderrama, and Anne Goodchild. (2018) An Evaluation of Logistics Sprawl in Chicago and Phoenix. Journal of Transport Geography, 88, 102298–. https://doi.org/10.1016/j.jtrangeo.2018.08.008