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Paper

Measurement and Classification of Transit Delays Using GTFS-RT Data

Publication: Public Transport
Volume: 14
Pages: 263-285
Publication Date: 2022
Summary:

This paper presents a method for extracting transit performance metrics from a General Transit Feed Specification’s Real-Time (GTFS-RT) component and aggregating them to roadway segments. A framework is then used to analyze this data in terms of consistent, predictable delays (systematic delays) and random variation on a segment-by-segment basis (stochastic delays). All methods and datasets used are generalizable to transit systems which report vehicle locations in terms of GTFS-RT parameters. This provides a network-wide screening tool that can be used to determine locations where reactive treatments (e.g., schedule padding) or proactive infrastructural changes (e.g., bus-only lanes, transit signal priority) may be effective at improving efficiency and reliability. To demonstrate this framework, a case study is performed regarding one year of GTFS-RT data retrieved from the King County Metro bus network in Seattle, Washington. Stochastic and systematic delays were calculated and assigned to segments in the network, providing insight to spatial trends in reliability and efficiency. Findings for the study network suggest that high-pace segments create an opportunity for large, stochastic speedups, while the network as a whole may carry excessive schedule padding. In addition to the static analysis discussed in this paper, an online interactive visualization tool was developed to display ongoing performance measures in the case study region. All code is open-source to encourage additional generalizable work on the GTFS-RT standard.

Authors: Dr. Andisheh Ranjbari, Zack Aemmer, Don MacKenzie
Recommended Citation:
Aemmer, Z., Ranjbari, A. & MacKenzie, D. Measurement and classification of transit delays using GTFS-RT data. Public Transp 14, 263–285 (2022). https://doi.org/10.1007/s12469-022-00291-7.
Paper

Understanding Urban Commercial Vehicle Driver Behaviors and Decision Making

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

As e-commerce 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 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 (1), 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 policymakers 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 (2). Lack of data results in a lack of fundamental knowledge of the urban freight system, inhibiting policy makers’ ability to make data-driven decisions (3).

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. (5) 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. (5) 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:
Dalla Chiara, G., Krutein, K. F., Ranjbari, A., & Goodchild, A. (2021). Understanding Urban Commercial Vehicle Driver Behaviors and Decision Making. Transportation Research Record: Journal of the Transportation Research Board, 036119812110035. https://doi.org/10.1177/03611981211003575.
Paper

Lessons from Tests of Electronic Container Door Seals

Publication: Transportation Research Board 88th Annual Meeting
Publication Date: 2009
Summary:
A series of field operational tests completed by Washington State over a 10-year period has shown that electronic container door seals (E-seals) can increase the efficiency and improve the security of containerized cargo movement. Universal use of E-seals, along with the associated infrastructure, could provide notable improvements in security, container tracking, and transaction cost reductions. Testing in ports, border facilities, and on roadways proved that E-Seal technology works: E-Seals can accurately and automatically report on container status at choke points, and the records can be accessed online to verify seal location, status (tampered or untampered), date, and time. However, a number of institutional barriers are likely to delay or even forestall the adoption of E-seals. A lack of standards is a major issue, since the E-seals available today use many different frequencies, hindering their applicability to international trade flows. A further barrier is the acceptability and cost of E-seals to the container industry. Routine use of seals would require new software linkages and container sealing procedures, which could slow acceptance. Disposable seals, which eliminate the need to recycle E-seals, are not common because they need to be produced in large quantities to be low cost. E-seals acceptable to the industry also need to be proved in a real world trade environment and need to be functionally simple to reduce routine operational problems. Compatibility with existing highway transponders systems might also promote E-seal acceptance, since containers could be tracked on the roadway system.

 

 

Authors: Dr. Ed McCormack, Mark Jensen, Al Hovde
Recommended Citation:
McCormack, E., Jensen, M., & Hovde, A. (2009). Lessons from Tests of Electronic Container Door Seals (No. 09-0821).
Paper

Rails-Next-to-Trails: A Methodology for Selecting Appropriate Safety Treatments at Complex Multimodal Intersections

 
Publication: Transportation Research Record
Volume: 2672 (10)
Pages: 27-Dec
Publication Date: 2018
Summary:
There are more than 212,000 at-grade railroad crossings in the United States. Several feature paths running adjacent to the railroad tracks, and crossing a highway; they serve urban areas, recreational activities, light rail station access, and a variety of other purposes. Some of these crossings see a disproportionate number of violations and conflicts between rail, vehicles, and pedestrians and bikes. This research focuses on developing a methodology for appropriately addressing the question of treatments in these complex, multimodal intersections. The methodology is designed to be able to balance a predetermined, prescriptive approach with the professional judgment of the agency carrying out the investigation. Using knowledge and data from the literature, field studies, and video observations, a framework for selecting treatments based on primary issues at a given location is developed. Using such a framework allows the agency to streamline their crossing improvement efforts; to easily communicate and inform the public of the decisions made and their reasons for doing so; to secure stakeholder buy-in prior to starting a project or investigation; to make sure that approach and selected treatments are more standardized; and to ensure transparency in the organization to make at-grade crossings safer for pedestrians and bicyclists, without negatively impacting trains or vehicles.

 

Paper

NCFRP Report: Smart Growth and Urban Goods Movement

 
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Publication: TR News
Volume: 295
Publication Date: 2014
Summary:

Smart growth design, a strategy for improving the quality of life in urban areas, has typically focused on the areas of passenger travel, land use and nonmotorized transport adoption. The role of goods movement is often ignored in discussions of smart growth. This article reports on National Cooperative Freight Research Program (NCFRP) Report 24, which addresses the importance of the relationship between smart growth and goods movement. A number of principles of smart growth are identified, as are areas where there are research gaps. Urban transportation forecasting models have shown that smart-growth land use offers benefits both for passenger travel and goods movement. Additionally, smart-growth improvements to transit and nonmotorized transportation have been found to offer greater benefits to trucks than do roadway investments.

Authors: Dr. Anne GoodchildDr. Ed McCormack, Alon Bassok
Recommended Citation:
McCormack, Ed, Anne Goodchild, and Alon Bassok. National Academies of Sciences, Engineering, and Medicine. 2013. Smart Growth and Urban Goods Movement. Washington, DC: The National Academies Press. https://doi.org/10.17226/22522.
Paper

A Competitive, Charter Air-Service Planning Model for Student Athlete Travel

Publication: Transportation Research Part B: Methodological
Volume: 45 (1)
Pages: 128-149
Publication Date: 2011
Summary:

This paper presents a model for planning an air charter service for pre-scheduled group travel. This model is used to investigate the competitiveness of such an enterprise for student athlete travel in conference sports. The relevant demand subset to be served by a limited charter fleet is identified through a comparison with existing scheduled travel options. Further, the routing and scheduling of the charter aircraft is performed within the same framework. Through this modeling a method for formulating and accommodating continuous time windows and competitive market dynamics in strategic planning for a charter service is developed. Computational improvements to the basic model are also presented and tested. The model is applied to the Big Sky Conference for the 2006–2007 season, quantifying the benefits to the students from such a service and the change in expenditure associated with such a benefit for various assumptions about operations and value of time. The findings indicate the lack of spatial or sport based patterns for maximizing benefit, indicating the absence of simplistic “rules of thumb” for operating such a service, and validating the need for the model.

Authors: Dr. Anne Goodchild, Gautam Gupta, and Mark Hansen
Recommended Citation:
Gautam Gupta, Anne Goodchild, and Mark Hansen (2011). A Competitive, Charter Air-Service Planning Model for Student Athlete Travel. Transportation Research Part B, 45, 128-149.
Paper

Measuring Truck Travel Time Reliability Using Truck Probe GPS Data

 
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Publication: Journal of Intelligent Transportation Systems: Technology, Planning, and Operations
Publication Date: 2015
Summary:

Truck probe data collected by global positioning system (GPS) devices has gained increased attention as a source of truck mobility data, including measuring truck travel time reliability. Most reliability studies that apply GPS data are based on travel time observations retrieved from GPS data. The major challenges to using GPS data are small, nonrandom observation sets and low reading frequency. In contrast, using GPS spot speed (instantaneous speed recorded by GPS devices) directly can address these concerns. However, a recently introduced GPS spot-speed-based reliability metric that uses speed distribution does not provide a numerical value that would allow for a quantitative evaluation. In light of this, the research described in this article improves the current GPS spot speed distribution-based reliability approach by calculating the speed distribution coefficient of variation. An empirical investigation of truck travel time reliability on Interstate 5 in Seattle, WA, is performed. In addition, correlations are provided between the improved approach and a number of commonly used reliability measures. The reliability measures are not highly correlated, demonstrating that different measures provide different conclusions for the same underlying data and traffic conditions. The advantages and disadvantages of each measure are discussed and recommendations of the appropriate measures for different applications are presented.

Recommended Citation:
Wang, Zun. Anne Goodchild, and Edward McCormack. "Measuring truck travel time reliability using truck probe GPS data." Journal of Intelligent Transportation Systems 20, no. 2 (2016): 103-112.
Paper

Intra-Industry Trade Analysis of U.S. State – Canadian Province Pairs: Implications for the Cost of Border Delay

Publication: Transportation Research Record
Volume: 2162
Pages: 73-80
Publication Date: 2010
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). The Grubel-Lloyd index, which measures IIT, is used to analyze trade in these two corridors. Higher levels of IIT and regional integration within the Great Lakes gateway are shown. The paper argues that cross-border supply chains most exposed to higher cost from increasing border delays are composed of horizontally differentiated manufactured goods having high levels of IIT and relying heavily on truck transportation. These types of goods are more common in the Great Lakes gateway, and this region may therefore experience greater economic impacts from long and unpredictable delays than the Cascade gateway.

Authors: Dr. Anne Goodchild, Kristján Kristjánsson, Michael Bomba
Recommended Citation:
Kristjánsson, Kristján Árni, Michael Bomba, and Anne V. Goodchild. "Intra-industry trade analysis of US state–Canadian province pairs: implications for the cost of border delay." Transportation Research Record 2162, no. 1 (2010): 73-80. 
Paper

Toward Predicting Stay Time for Private Car Users: A RNN-NALU Approach

 
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Publication: IEEE Transactions on Vehicular Technology
Volume: 71 (6)
Pages: 6007 - 6018
Publication Date: 2022
Summary:

Predicting the stay time of private cars has various applications in location-based services and traffic management. Due to the associated randomness and uncertainty, achieving the promising performance of stay time prediction is a challenge. We propose an RNN-based encoder model to solve this problem, which consists of three components, i.e., an encoder module, an exception module, and an MLP dropout. First, we encode the stay behaviour into hidden vectors at a specific time to avoid the effect of time sparsity. The encoder module utilizes a multilayer perceptron (MLP) to learn spatiotemporal features from the historical trajectory data, such as the inherent relationship between the stop points and corresponding stay time. We proved a linear relationship problem that cannot be ignored in the stay time prediction problem. In particular, we have added basic arithmetic logic units to the network framework to find linear relationships. By reconstructing the basic arithmetic and logical relations of the network, we have improved the ability of the neural network to handle linear relations and the extrapolation ability of the neural network. Our method can remember the number patterns seen in the training set very well and infer this representation reasonably. Moreover, we utilize the dropout technique to prevent the prediction model from overfitting. We perform extensive experiments based on a large-scale real-world private car trajectory dataset. The experimental results demonstrate that our method achieves an RMSE of 0.1429 and a MAPE of 55.8533%. Furthermore, the results verify the effectiveness and advantages of the proposed model when compared with the benchmarks.

Authors: Amelia Regan, Qibo Zhang; Fanzi Zeng; Zhu Xiao; Hongbo Jiang; Kehua Yang; Yongdong Zhu
Recommended Citation:
Q. Zhang et al., "Toward Predicting Stay Time for Private Car Users: A RNN-NALU Approach," in IEEE Transactions on Vehicular Technology, vol. 71, no. 6, pp. 6007-6018, June 2022, doi: 10.1109/TVT.2022.3164978.
Paper

Systematic Approach for the Design of Flight Simulator Studies

 
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Publication: Proceedings of the Human Factors and Ergonomics Society 2019 Annual Meeting
Volume: 63:01:00
Pages: 833-837
Publication Date: 2019
Summary:

The examination of commercial pilot workload often requires the use of controlled simulated studies to identify causal effects. The specific scenarios to consider within a simulator study require an extensive understanding of the safety situations that can occur in flight while also considering the specific training that pilots are provided within a simulated environment. The purpose of this paper is to provide a more systematic approach to scenario identification based on historical data, feasibility of capturing behavioral changes, simulator constraints, and training curricula.

Authors: Fiete Krutein, Linda Ng Boyle
Recommended Citation:
Krutein, K. F., & Boyle, L. N. (2019). Systematic approach for the design of flight simulator studies. Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 63(1), 833–837. https://doi.org/10.1177/1071181319631524