Transportation Engineering Commons^™

Developing A Computer Vision-Based Decision Support System For Intersection Safety Monitoring And Assessment Of Vulnerable Road Users, Arash Jahangiri, Anagha Katthe, Aryan Sohrabi, Xiaobai Liu, Shashank Pulagam, Vahid Balali, Sahar Ghanipoor Machiani

Mineta Transportation Institute

Vision-based trajectory analysis of road users enables identification of near-crash situations and proactive safety monitoring. The two most widely used sur-rogate safety measures (SSMs), time-to-collision (TTC) and post-encroachment time (PET)—and a recent variant form of TTC, relative time-to-collision (RTTC)—were investigated using real-world video data collected at ten signalized intersections in the city of San Diego, California. The performance of these SSMs was compared for the purpose of evaluating pedestrian and bicyclist safety. Prediction of potential trajectory intersection points was performed to calculate TTC for every interacting object, and the average of TTC for every two objects in critical situations was …

Analysis And Assessment Of The Reimbursement Rates And Mechanisms For Kentucky’S Publicly Funded Ferries, P. Gayle Marks, Bryan Gibson, Andrew Martin, Steven Douglas Kreis

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) reimburses publicly operated ferries, including when they cease operations due to severe weather or unforeseen events. Reimbursement procedures are not codified in law and are largely based on historical practice. To determine how the Cabinet should handle reimbursement, funding, oversight of ferry services moving forward, the Kentucky Transportation Center (KTC) reviewed practices adopted by 10 other states and conducted a detailed analysis of Kentucky’s current approach. Of the states KTC examined, only Tennessee reimburses ferry operations for closures (at 50 percent of the normal hourly rate for a period up to 48 hours). Half of …

Improving Construction Work Zone Safety Using Technology: A Systematic Review Of Applicable Technologies, Chukwuma Nnaji, John Gambatese, Hyun Woo Lee, Fan Zhang

Faculty Publications

© 2019 The Authors Once considered conventional, the construction industry is gradually increasing its reliance on innovations such as the application of technologies in safety management. Given the growing literature on technology applications in safety management and the varying opinions on the utility of applied technologies, a systematic review that streamlines findings from past studies is indispensable to construction stakeholders. Although a number of review studies are available in the building construction sector, the level of fragmentation and uniqueness within the construction industry necessitates a review study specifically targeting the heavy civil sector. In response, the present study applies a …

A New Materials And Design Approach For Roads, Bridges, Pavement, And Concrete, Alan Fuchs, Tathagata Acharya, Luis Cabrales, Jesse Bergkamp, Nyakundi Michieka

Mineta Transportation Institute

Increased understanding of demand for transport energy and how to improve road pavement materials would enable decision makers to make environmental, financial, and other positive changes in future planning and design of roads, bridges, and other important transportation structures. This research comprises three studies focused on pavement materials and a fourth study that examines energy demand within the road transportation sector. These studies are as follows:

1. A techno-economic study of ground tire rubber as an asphalt modifier;

2. A computational fluid dynamics analysis comparing the urban heat island effect of two different pavement materials – asphalt and Portland Cement …

The Potential For Autonomous Vehicle Technologies To Address Barriers To Driving For Individuals With Autism, Caroline Rodier

Mineta Transportation Institute

Individuals with autism represent a sizeable share of the U.S. population (almost 2%), and nearly half of those with autism have average to high levels of intelligence. However, available research shows that adults with autism have a much more difficult time becoming employed and living independently compared to both typically developing adults and adults with disabilities. This study reviews the available literature on the magnitude of challenges to driving and accessing essential opportunities for adults with autism, and the potential of autonomous vehicles to address those challenges. This study is unique in that it identifies the specific driving challenges and …

A Smart Growth & Equity Framework And Tool For Measuring, Understanding, And Realizing Transportation Land Use Coordination For Sustainability, Livability, And Equity, Bruce Appleyard, Chris Allen, Jonathan Stanton

Mineta Transportation Institute

The coordination and integration of transportation and land use (also known as “smart growth”) has been a long-standing goal for planning and engineering professionals, but to this day remains an elusive concept to realize. As this approach is a widely recognized as key to achieving sustainable, livable, and equitable (SLE) outcomes for individuals and society, a key aim of this report is to instill the coordination of transportation and land use into practice by the collection of key actors and agents (MPOs, DOTs, and local land use authorities, etc.) through new measurement and policy guidance frameworks and tools. A fundamental …

Early Detection Of Near-Surface Void Defects In Concrete Pavement Using Drone Based Thermography And Gpr Methods, Zhigang Shen, Ece Erdogmus, George Morcous, Chngsheng Cheng, Zhexiong Shang, Theresa Mccabe, Antony Mohsen Kamal Masoud Kodsy

Nebraska Department of Transportation: Research Reports

The goal of this research is to evaluate the feasibility and the performance of using UAV-mounted infrared thermography (IRT) and ground penetration radar (GPR) to detect sub-surface voids caused by consolidation issues in concrete pavement. The motivation of the study is to identify the consolidation defects as early as the initial set of concrete to avoid having this problem in large pavement sections, which is costly and time consuming to repair. Using the two technologies in combination to detect subsurface voids in the concrete initial set stage is new and aims to take advantage of the strengths and minimize the …

Optfill: A Tool For Infeasible Cycle-Free Gapfilling Of Stoichiometric Metabolic Models, Wheaton L. Schroeder, Rajib Saha

Mid-America Transportation Center: Final Reports and Technical Briefs

Stoichiometric metabolic modeling, particularly genome-scale models (GSMs), is now an indispens- able tool for systems biology. The model reconstruction process typically involves collecting informa- tion from public databases; however, incomplete systems knowledge leaves gaps in any reconstruc- tion. Current tools for addressing gaps use databases of biochemical functionalities to address gaps on a per-metabolite basis and can provide multiple solutions but cannot avoid thermodynami- cally infeasible cycles (TICs), invariably requiring lengthy manual curation. To address these limita- tions, this work introduces an optimization-based multi-step method named OptFill, which performs TIC-avoiding whole-model gapfilling. We applied OptFill to three fictional prokaryotic models …

Calibrating The Highway Capacity Manual Arterial Travel Time Reliability Model, Ernest Tufuor, Laurence Rilett, Li Zhao

Mid-America Transportation Center: Final Reports and Technical Briefs

The latest edition of the Highway Capacity Manual (HCM-6) includes, for the first time, a methodology for estimating and predicting the average travel time distribution (TTD) of urban streets. Travel time reliability (TTR) metrics can then be estimated from the TTD. The HCM-6 explicitly considers five key sources of travel time variability. A literature search showed no evidence that the HCM-6 TTR model has ever been calibrated with empirical travel time data. More importantly, previous research showed that the HCM-6 underestimated the empirical TTD variability by 70% on a testbed in Lincoln, Nebraska. In other words, the HCM-6 TTR metrics …

Analysis Of Component Errors In The Highway Capacity Manual Travel Time Reliability Estimations For Urban Streets, Ernest Tufuor, Laurence Rilett

Mid-America Transportation Center: Final Reports and Technical Briefs

The Highway Capacity Manual 6th edition (HCM6) includes a new methodology to estimate and predict the distribution of average travel times (TTD) for urban streets. The TTD can then be used to estimate travel time reliability (TTR) metrics. Previous research on a 0.5-mi testbed showed statistically significant differences between the HCM6 estimated TTD and the corresponding empirical TTD. The difference in average travel time was 4 s that, while statistically significant, is not important from a practical perspective. More importantly, the TTD variance was underestimated by 70%. In other words, the HCM6 results reflected a more reliable testbed than field …

Análisis Por Confiabilidad Del Modelo De Diseño Aashto 93 Para Pavimentos Flexibles En El Valle De Aburrá, Mario Santiago Hernández, Juan Pablo Osorio, Juan Camilo Viviescas

Books/Book Chapters

La necesidad de construir pavimentos con mejores especificaciones técnicas y mayores períodos de servicio requiere de una modelación rigurosa de la variabilidad en las propiedades geotécnicas con el fin de garantizar la confiabilidad de estas estructuras. Por lo tanto, se realizó un análisis basado en la confiabilidad del método Aashto-93, considerando la variabilidad geotécnica del suelo, asociada al módulo resiliente de la subrasante. Los diseños por confiabilidad fueron efectuados de acuerdo con las categorías, parámetros y estructuras establecidas por el Manual de diseño de pavimentos asfálticos en vías con medios y altos volúmenes de tránsito, de 1998, del Instituto Nacional …

An Integrated Computational And Experimental Study To Investigate Staphylococcus Aureus Metabolism, Mohammad Mazharul Islam, Vinai C. Thomas, Matthew Van Beek, Jong-Sam Ahn, Abdulelah A. Alqarzaee, Chunyi Zhou, Paul D. Fey, Kenneth W. Bayles, Rajib Saha

Mid-America Transportation Center: Final Reports and Technical Briefs

Staphylococcus aureus is a metabolically versatile pathogen that colonizes nearly all organs of the human body. A detailed and comprehensive knowledge of staphylococcal metabolism is essential to understand its pathogenesis. To this end, we have reconstructed and experimentally validated an updated and enhanced genome-scale metabolic model of S. aureus USA300_FPR3757. The model combined genome annotation data, reaction stoichiometry, and regulation information from biochemical databases and previous strain-specific models. Reactions in the model were checked and fixed to ensure chemical balance and thermodynamic consistency. To further refine the model, growth assessment of 1920 nonessential mutants from the Nebraska Transposon Mutant Library …

Civil Engineering Research In Ireland 2020: Conference Proceedings, Kieran Ruane, Vesna Jaksic, Bidisha Ghosh, Magdalena Hajdukiewicz, Ciaran Hanley, Niall Holmes, Jennifer Keenahan, Zili Li, Patrick Mcgetrick, Ted Mckenna, Mary Moloney, Vikram Pakrashi, Niamh Power

Publications

Civil Engineering Research in Ireland 2020: Conference Proceedings.

Safety Evaluation Of Innovative Intersection Designs: Diverging Diamond Interchanges And Displaced Left-Turn Intersections, Ahmed Abdelrahman

Electronic Theses and Dissertations, 2020-2023

Diverging diamond interchanges (DDIs) and Displaced left-turn intersections (DLTs) are designed to enhance the operational performance of conventional intersections that are congested due to heavy left-turn traffic volumes. Since drivers are not familiar with these types of intersections, there is a need to evaluate their safety performance to validate their effect, and to estimate reliable and representative Crash Modification Factors (CMFs). The safety evaluation was conducted based on three common safety assessment methods, which are before-and-after study with comparison group, Empirical Bayes before-and-after method, and cross-sectional analysis. Furthermore, since DLTs showed poor safety performance, the study also investigated the operational …

Development Of An Ndt Tool For In-Situ Assessment Of Prestress Loss, Bibo Zhong, Jinying Zhu, George Morcous

Nebraska Department of Transportation: Research Reports

The research objective is to develop a non-destructive testing (NDT) method to evaluate the prestress loss in prestressed concrete bridge girders using ultrasonic waves. The work principle is based on acoustoelastic effect - ultrasonic wave velocity varies with stress level in prestressed concrete. A self-reference test setup was proposed to measure wave velocity in two orthogonal directions (prestress and unstressed directions) in the girder. This setup will be able to reduce effects of material variation and temperature change.

The concept was first validated on small concrete specimens (cylinders and beams) in laboratory. A signal analysis algorithm was developed to reliably …

Smartphone Sensor-Based Pedestrian Activity Recognition For P2v Communication And Warning System, Dhrubo Hasan Chowdhury

Electronic Theses and Dissertations, 2020-2023

The ubiquity of smartphones has made a remarkable influence on everyone's day to day life. Variety of useful built-in sensors provide smartphones with a convenient floor for data collection and analysis. Application development based on the user's location and movement is not a difficult task nowadays. But injuries and deaths due to smartphone-distracted movement on roadways is on the increase. This study explores the capabilities of smartphone inertial sensors for pedestrian activity recognition. Smartphone distracted movements can be predicted from the associated pedestrian's posture, thus inertial sensors can provide effective solution for this specific task. Volunteers were asked to perform …

Traffic Speed Prediction And Mobility Behavior Analysis Using On-Demand Ride-Hailing Service Data, Jiechao Zhang

Electronic Theses and Dissertations, 2020-2023

Providing accurate traffic speed prediction is essential for the success of Intelligent Transportation Systems (ITS) deployments. Accurate traffic speed prediction allows traffic managers take proper countermeasures when emergent changes happen in the transportation network. In this thesis, we present a computationally less expensive machine learning approach XGBoost to predict the future travel speed of a selected sub-network in Beijing's transportation network. We perform different experiments for predicting speed in the network from future 1 min to 20 min. We compare the XGBoost approach against other well-known machine learning and statistical models such as linear regression and decision tree, gradient boosting …

Prediction Of Pedestrians' Red Light Violations Using Deep Learning, Shile Zhang

Electronic Theses and Dissertations, 2020-2023

Pedestrians are regarded as Vulnerable Road Users (VRUs). Each year, thousands of pedestrians' deaths are caused by traffic crashes, which take up 16% of the total road fatalities and injuries in the U.S. (FHWA, 2018). Crashes can happen if there are interactions between VRUs and motorized transportation. And pedestrians' unexpected crossings, such as red-light violations at the signalized intersections, would expose them to motorized transportation and cause potential collisions. This thesis is intended to predict the pedestrians' red-light violation behaviors at the signalized crosswalks based on an LSTM (Long Short-term Memory) neural network. With video data collected from real traffic …

Effect Of Temporal Instability Of Factors Contributing To Single-Vehicle Crash Severity--A Mixed Logit Approach, A. M. Hasibul Islam

Theses and Dissertations--Civil Engineering

This study investigates the factors associated with single-vehicle crash injury severity using five years (2014 – 2018) of crash data from Kentucky, USA, using a mixed (random-parameter) logit model. We also explore the temporal heterogeneity of the correlated factors across different times of the day. Most crash-severity models assume that the estimated parameters remain temporally stable. For instance, the effect of light conditions on crash severity may differ based on the time of the crash occurrence—noon vs. dusk. The temporal instability of the factors due to the time-of-day variation can lead to (under) overestimating the parameters that influence the development …

Valuing Public Transport Customer Amenities: International Transit Agency Practice, Chris De Gruyter, Graham Currie

Journal of Public Transportation

Public transport customer amenities cover a range of measures that can enhance the quality of the passenger experience, such as information provision and station quality. While much research has determined the value that users place on amenities, there is little understanding of current practice in the use of customer amenity valuations in project appraisal. A survey of transit agencies in 11 cities (Melbourne, Sydney, Brisbane, Perth, Auckland, London, Paris, Toronto, Vienna, Oslo and Singapore) was undertaken showing that Australasian cities, albeit Melbourne, generally have widespread inclusion of customer amenities as part of advanced appraisals for all relevant types of public …