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Paper

An Analytical Model for Vehicle Miles Traveled and Carbon Emissions for Goods Delivery Scenarios

 
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Publication: European Transport Research Review
Volume: 10
Publication Date: 2018
Summary:

This paper presents an analytical model to contrast the carbon emissions from a number of goods delivery methods. This includes individuals travelling to the store by car, and delivery trucks delivering to homes. While the impact of growing home delivery services has been studied with combinatorial approaches, those approaches do not allow for systematic conclusions regarding when the service provides net benefit. The use of the analytical approach presented here, allows for more systematic relationships to be established between problem parameters, and therefore broader conclusions regarding when delivery services may provide a CO2 benefit over personal travel.

Methods

Analytical mathematical models are developed to approximate total vehicle miles traveled (VMT) and carbon emissions for a personal vehicle travel scenario, a local depot vehicle travel scenario, and a regional warehouse travel scenario. A graphical heuristic is developed to compare the carbon emissions of a personal vehicle travel scenario and local depot delivery scenario.

Results

The analytical approach developed and presented in the paper demonstrates that two key variables drive whether a delivery service or personal travel will provide a lower CO2 solution. These are the emissions ratio, and customer density. The emissions ratio represents the relative emissions impact of the delivery vehicle when compared to the personal vehicle. The results show that with a small number of customers, and low emissions ratio, personal travel is preferred. In contrast, with a high number of customers and low emissions ratio, delivery service is preferred.

Conclusions

While other research into the impact of delivery services on CO2 emissions has generally used a combinatorial approach, this paper considers the problem using an analytical model. A detailed simulation can provide locational specificity, but provides less insight into the fundamental drivers of system behavior. The analytical approach exposes the problem’s basic relationships that are independent of local geography and infrastructure. The result is a simple method for identifying context when personal travel, or delivery service, is more CO2 efficient.

Authors: Dr. Anne Goodchild, Erica Wygonik, Nathan Mayes
Recommended Citation:
Goodchild, Anne, Erica Wygonik, and Nathan Mayes. "An analytical model for vehicle miles traveled and carbon emissions for goods delivery scenarios." European Transport Research Review 10, no. 1 (2018): 8.
Paper

The Rise of Mega Distribution Centers and the Impact on Logistical Uncertainty

 
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Publication: Transportation Letters: The International Journal of Transportation Research
Volume: 2 (2)
Pages: 75-88
Publication Date: 2010
Summary:

Between 1998 and 2005, employment in the U.S. warehousing industry grew at a compound annual growth rate of 22.23%, and the number of establishments increased at compound annual growth rate of 9.48%. Over this same period of time, the price for transportation fuels increased dramatically and became much more volatile. In this paper we examine the microeconomic and macroeconomic forces that have enabled such rapid growth in the warehousing industry. We also analyze structural change through employment and warehouse construction starts data and show that a new breed of warehouse has emerged – the mega distribution center, or mega DC. Mega DCs serve mega markets, which allows them to gain advantage through economies of scale and by employing push-pull supply chain strategies that decrease the uncertainty associated with forecasting market demand. Our geographical analyses suggest that this new breed of mega DC is attracted to locations that optimize access to multiple regional markets (and possibly national markets) at the expense of optimizing access to any single market. On average the length of the final leg of the supply chain becomes longer. Because the last leg must be made by truck — which is the least fuel-efficient mode of transport by far — the location requirements of this new breed of mega DC increase supply chain exposure to the related risks of rising and increasingly volatile fuel prices.

Authors: Dr. Anne Goodchild, Derik Andreoli, Kate Vitasek
Recommended Citation:
Andreoli, Derik, Anne Goodchild, and Kate Vitasek. "The Rise of Mega Distribution Centers and the Impact on Logistical Uncertainty." Transportation Letters 2, no. 2 (2010): 75-88.
Paper

Evaluating Two Low-Cost Methods of Collecting Truck Generation Data Using Grocery Stores

 
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Publication: Institute of Transportation Engineers (ITE) Journal
Volume: 81 (6)
Pages: 34–40
Publication Date: 2011
Summary:

Despite their heavy use of the road transportation system, little data is available on trip generation rates for trucks. In this paper, truck trip rates from grocery stores are used in a case study to evaluate and compare two simple methods for collecting data on truck trip generation: telephone interviews and manual counts. The findings from this study showed that grocery stores generated an average of 18 truck trips per day on a typical peak period weekday. The results also showed that a combination of telephone interviews and manual counts was more effective than telephone interviews alone. Information from the telephone interview guided the manual counts and provided a baseline measurement of counts. However, the interviews underreported truck trips when compared to the manual observations.

Authors: Dr. Ed McCormack, Alon Bassok
Recommended Citation:
McCormack, Edward, and Alon Bassok. "Evaluating Two Low-Cost Methods of Collecting Truck Generation Data Using Grocery Stores." Institute of Transportation Engineers. ITE Journal 81, no. 6 (2011): 34.
Paper

Building Resilience into Freight Transportation Systems: Actions for State Departments of Transportation

 
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Publication: Transportation Research Record: Journal of the Transportation Research Board
Volume: 2168
Pages: 129-135
Publication Date: 2010
Summary:

The management of transportation systems for resilience has received significant attention in recent years. Resilience planning concerns the actions of an organization that reduce the consequences of a disruption to the system the organization manages. Little exploration has been made into the connections between resilience planning and the actions of a state department of transportation (DOT) that contribute to resilience of a freight transportation system. Conclusions are presented from collaborative research between the Washington State DOT Freight Systems Division (WSDOT FSD) and researchers at the University of Washington. Activities of the WSDOT FSD that contribute to resilience are identified, and one such activity undertaken by WSDOT to improve communication with system users is described. This and other activities can be undertaken by other DOTs that want to improve the resilience of their freight transportation systems at relatively low cost.

Authors: Dr. Anne GoodchildBarbara Ivanov, Chilan Ta
Recommended Citation:
Ta, Chilan, Anne V. Goodchild, and Barbara Ivanov. "Building Resilience into Freight Transportation Systems: Actions for State Departments of Transportation." Transportation Research Record 2168, no. 1 (2010): 129-135.
Paper

Analyzing the Effect of Autonomous Ridehailing on Transit Ridership: Competitor or Desirable First-/Last-Mile Connection?

 
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Publication: Transportation Research Record
Volume: 2675 (11)
Pages: 1154-1167
Publication Date: 2021
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. To that end, a stated preference survey was launched around the US to ask 1,500 commuters how they would choose their commute mode from among choices including their current mode and other conventional modes as well as asking them to choose between their current mode and an autonomous mode. Using a joint stated and revealed preference dataset, a mixed logit model was developed and analyzed.

Authors: Dr. Andisheh Ranjbari, Moein Khaloei, Ken Laberteaux, Don MacKenzie
Recommended Citation:
Khaloei, M., Ranjbari, A., Laberteaux, K., & MacKenzie, D. (2021). Analyzing the Effect of Autonomous Ridehailing on Transit Ridership: Competitor or Desirable First-/Last-Mile Connection? Transportation Research Record, 2675(11), 1154–1167. https://doi.org/10.1177/03611981211025278
Paper

Evaluating Traffic Impacts of Permitting Trucks in Transit-Only Lanes

 
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Publication: Transportation Research Record: Journal of the Transportation Research Board
Publication Date: 2021
Summary:

With ongoing population growth and rapid development in cities, the demand for goods and services has seen a drastic increase. Consequently, transportation planners are searching for new ways to better manage the flow of traffic on existing facilities, and more efficiently utilize available and unused capacity. In this research, a lane management strategy that allows freight vehicles to use bus-only lanes is empirically evaluated in an urban setting. This paper presents an analysis of data that was collected to evaluate the operational impacts of the implementation of a freight and transit (FAT) lane, and to guide the development of future FAT lane projects by learning from the case study in Seattle, U.S. The video data was converted to vehicle counts, which were analyzed to understand the traffic impacts and used to construct a discrete choice model. The analysis shows that transit buses used the FAT lane 96% of the time, and authorizing trucks to use the lane did not affect that lane choice. Trucks used the FAT lane, but their utilization decreased with increasing numbers of buses in the FAT lane. Instead of higher rates of trucks, unauthorized vehicles, such as passenger cars and work vans, increasingly used the FAT lane during congestion. As a result of their differing schedule patterns, trucks and buses used the FAT lane at complementary times and trucks showed relatively low volumes in the FAT lane. Overall, the results are promising for a lane management strategy that may improve freight system performance without reducing transit service quality.

Recommended Citation:
Gunes, S., Goodchild, A., Greene, C., & Nemani, V. (2021). Evaluating Traffic Impacts of Permitting Trucks in Transit-Only Lanes. Transportation Research Record. https://doi.org/10.1177/03611981211031888
Paper

The Impact of Weather on Bus Ridership in Pierce County, Washington

 
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Publication: Journal of Public Transportation
Publication Date: 2012
Summary:
A factor that influences transit ridership but has not received much attention from researchers is weather. This paper examines the effects of weather on bus ridership in Pierce County, Washington, for the years 2006–2008. Separate ordinary least squares regression models were estimated for each season, as weather conditions may have different effects depending on the time of year. Four weather variables were considered: wind, temperature, rain, and snow. High winds negatively affected ridership in winter, spring, and autumn. Cold temperatures led to decreases in ridership in winter. Rain negatively affected ridership in all four seasons, and snow was associated with lower ridership in autumn and winter. These results suggest that adverse weather conditions can have a negative effect on transit ridership.

 

 

Authors: Dr. Ed McCormack, Victor W. Stover
Recommended Citation:
Stover, V. W., & McCormack, E. D. (2012). The Impact of Weather on Bus Ridership in Pierce County, Washington. Journal of Public Transportation, 15(1), 6.
Paper

Commercial Vehicle Parking in Downtown Seattle: Insights on the Battle for the Curb

 
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Publication: Transportation Research Record: Journal of the Transportation Research Board
Publication Date: 2019
Summary:

Rapid urban growth puts pressure on local governments to rethink how they manage street curb parking. Competition for space among road users and lack of adequate infrastructure force delivery drivers either to search for vacant spaces or to park in unsuitable areas, which negatively impacts road capacity and causes inconvenience to other users of the road.

The purpose of this paper is to advance research by providing data-based insight into what is actually happening at the curb. To achieve this objective, the research team developed and implemented a data collection method to quantify the usage of curb space in the densest urban area of Seattle, Center City.

This study captures the parking behavior of commercial vehicles everywhere along the block face as well as the parking activities of all vehicles (including passenger vehicles) in commercial vehicle loading zones. Based on the empirical findings, important characteristics of Seattle’s urban freight parking operations are described, including a detailed classification of vehicle types, dwell time distribution, and choice of curb use for parking (e.g., authorized and unauthorized spaces). The relationship between land use and commercial vehicle parking operations at the curb is discussed. Seattle’s parking management initiatives will benefit from the insights into current behavior gained from this research.

Rapid urban growth, increasing demand, and higher customer expectations have amplified the challenges of urban freight movement. Finding an adequate space to park can be a major challenge in urban areas. For commercial vehicles used for freight transportation and provision of services, the lack of parking spaces and parking policies that recognize those vehicles’ unique needs can have negative impacts that affect all users of the road, particularly the drivers of these commercial vehicles (1–4).

The curb is an important part of the public right-of-way. It provides a space for vehicles to park on-street; for delivery vehicles (i.e., cargo bikes, cargo vans, and trucks), in particular, it also provides a dedicated space for the loading and unloading of goods close to destinations. Hence it is a key asset for urban freight transportation planning which local governments can administer to support delivery and collection of goods.

According to Marcucci et al. (5), the development of sustainable management policies for urban logistics should be based on site-specific data given the heterogeneity and complexity of urban freight systems. Current loading/unloading parking policies include time restrictions, duration, pricing, space management, and enforcement (6, 7). However, as Marcucci et al. pointed out after an extensive review of the literature on freight parking policy, the quantification of commercial vehicle operations on the curb to inform policy decision making is nonexistent (5). Therefore, local governments often lack data about the current usage of the curb and parking infrastructure, which is necessary to evaluate and establish these policies and therefore make well-informed decisions regarding freight planning, especially in dense, constrained urban areas.

Given the importance of the curb as an essential piece of the load/unload infrastructure, this paper investigates what is actually happening at the curb, developing an evidence-based understanding of the current use of this infrastructure. The research team developed and applied a systematic data collection method resulting in empirical findings about the usage of public parking for loading and unloading operations in the Seattle downtown area.

This research documents and analyzes the parking patterns of commercial vehicles (i.e., delivery, service, waste management, and construction vehicles) in the area around five prototype buildings located in the Center City area. The results of this research will help to develop and inform parking management initiatives.

The paper includes four sections in addition to this introduction. The second section discusses previous freight parking studies and the existing freight parking policies in cities, and explores which of these approaches are being used in Seattle. The third section proposes a data collection method to document freight-related parking operations at the curb though direct observations. The fourth section provides empirical findings from data collection in Seattle. The fifth and last section includes a discussion of the findings and concluding remarks.

Recommended Citation:
Girón-Valderrama, Gabriela del Carmen, José Luis Machado-León, and Anne Goodchild. "Commercial Vehicle Parking in Downtown Seattle: Insights on the Battle for the Curb." Transportation Research Record (2019): 0361198119849062.
Paper

Review of Performance Metrics for Community-Based Planning for Resilience of the Transportation System

 
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Publication:  Transportation Research Record: Journal of the Transportation Research Board
Volume: 2604
Pages: 44-53
Publication Date: 2017
Summary:

Community resilience depends on the resilience of the lifeline infrastructure and the performance of the disaster-related functions of local governments. State and federal resilience plans and guidelines acknowledge the importance of the transportation system as a critical lifeline in planning for community resilience and in helping local governments to set recovery goals. However, a widely accepted definition of the resilience of the transportation system and a structure for its measurement are not available. This paper provides a literature review that summarizes the metrics used to assess the resilience of the transportation system and a categorization of the assessment approaches at three levels of analysis (the asset, network, and systems levels). Furthermore, this paper ties these metrics to relevant dimensions of community resilience. This work addresses a key first step required to enhance the efficiency of planning related to transportation system resilience by providing (a) a standard terminology with which efforts to enhance the resilience of the transportation system can be developed, (b) an approach to organize planning and research efforts related to the resilience of the transportation system, and (c) identification of the gaps in measurement of the performance of the resilience of the transportation system.

Recommended Citation:
Machado, Jose Luis, and Anne Goodchild. Review of Performance Metrics for Community-Based Planning for Resilience of the Transportation System. Transportation Research Record: Journal of the Transportation Research Board, Transportation Research Record, 2604(1), 44–53. https://doi.org/10.3141/2604-06
Paper

Impact of Truck Arrival Information on System Efficiency at Container Terminals

 
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Publication: Transportation Research Record: Journal of the Transportation Research Board
Volume: 2162
Publication Date: 2014
Summary:

This paper quantifies the benefits to drayage trucks and container terminals from a data-sharing strategy designed to improve operations at the drayage truck-container terminal interface. This paper proposes a simple rule for using truck information to reduce container rehandling work and suggests a method for evaluating yard crane productivity and truck transaction time. Various scenarios with different levels of information quality are considered to explore how information quality affects system efficiency (i.e., truck wait time and yard crane productivity). Different block configurations and truck arrival rates are also investigated to evaluate the effectiveness of truck information under various system configurations. The research demonstrates that a small amount of truck information can significantly improve crane productivity and reduce truck delay, especially for those terminals operating near capacity or using intensive container stacking, and that complete truck arrival sequence information is not necessary for system improvement.

Authors: Dr. Anne Goodchild, Wenjuan Zhao
Recommended Citation:
Zhao, Wenjuan, and Anne V. Goodchild. "Impact of truck arrival information on system efficiency at container terminals." Transportation Research Record 2162, no. 1 (2010): 17-24.