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Full-Text Articles in Engineering

Time-To-Failure Prediction Of Fine-Grained Soil Slopes Subject To Weather-Driven Deterioration, Arm M. Morsy Aug 2024

Time-To-Failure Prediction Of Fine-Grained Soil Slopes Subject To Weather-Driven Deterioration, Arm M. Morsy

Mineta Transportation Institute

Embankments have been widely used in the construction of transportation and flood defense infrastructure. Embankments constructed from clays experience a suite of weather-driven deterioration processes that lead to a progressive loss of hydromechanical performance, causing potentially severe and costly consequences. This study aimed to predict the time to failure of aging, deteriorating clay embankments supporting transportation infrastructure. A multi-phase numerical modeling approach was developed to replicate the long-term, weather-driven, hydromechanical behavior of clay embankments. This model simulated the behavior of a number of well-documented embankment failure case studies that had sufficient data to derive the necessary soil properties and climate …


Moving Towards The Electrification Of Medium- And Heavy-Duty Vehicles In The Inland Empire, Kimberly Collins, Raffi Der Wartanian, Francisca Beer, Yunfei Hou Aug 2024

Moving Towards The Electrification Of Medium- And Heavy-Duty Vehicles In The Inland Empire, Kimberly Collins, Raffi Der Wartanian, Francisca Beer, Yunfei Hou

Mineta Transportation Institute

This report investigates the transition to zero-emission medium- and heavy-duty vehicles (MDHD) within California’s Inland Empire (IE), emphasizing the significance of electric vehicle charging infrastructure and opportunity charging strategies in facilitating sustainable transportation. Utilizing a mixed-methods approach that combines a systematic literature review, geospatial and big data analytics, and thematic analysis of expert interviews, the study explores the multifaceted challenges and opportunities of electrification. The literature review assesses policies at various governance levels, while geospatial analysis identifies regional traffic patterns and infrastructure needs. Big data analytics examine vehicle movements, complemented by insights from interviews with 16 regional experts, offering a …


Battery Management System Development For Electric Vehicles And Fast Charging Infrastructure Improvement, Yu Yang, Hen-Geul Yeh, Cesar Ortiz Jul 2024

Battery Management System Development For Electric Vehicles And Fast Charging Infrastructure Improvement, Yu Yang, Hen-Geul Yeh, Cesar Ortiz

Mineta Transportation Institute

The electric vehicle (EV) has become increasingly popular due to its being zero-emission. However, a significant challenge faced by EV drivers is the range anxiety associated with battery usage. Addressing this concern, this project develops a more efficient battery management system (BMS) for electric vehicles based on a real-time, state-of-charge (SOC) estimation. The proposed study delivers three modules: (1) a new equivalent circuit model (ECM) for lithium-ion batteries, (2) a new SOC estimator based on the moving horizon method, and (3) an on-board FPGA implementation of the classical Coulomb counting method for SOC estimation. The research team extends the traditional …


Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures Phase 2, Andrea Calabrese, Pitiporn Asvapathanagul, Nisarg N. Patel, Nanubala Dhruvan, Austin Adams, Michael Hernandez, Douglas S. Lopez-Cruz Jul 2024

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures Phase 2, Andrea Calabrese, Pitiporn Asvapathanagul, Nisarg N. Patel, Nanubala Dhruvan, Austin Adams, Michael Hernandez, Douglas S. Lopez-Cruz

Mineta Transportation Institute

Concrete is a critical component of so much of the modern construction industry. This material, well known for its versatility, robustness, longevity, and strength, is well-suited for a wide range of structural applications. Nonetheless, the widespread occurrence of cracks in concrete structures, primarily attributed to its limited tensile strength, shrinkage, and overstain, imposes a considerable economic and environmental challenge when it comes to retrofitting these fissures. This study tackles this problem by harnessing bacteria tolerant to high alkaline conditions to enable Microbially Induced Calcium Carbonate Precipitation (MICP) for the self-repair of concrete. This is achieved through an external application method, …


Exploring Performance-Based Contracts: A Good Option To Address Long-Term Road Maintenance In California?, Maria Calahorra-Jimenez, Richard Poythress Jul 2024

Exploring Performance-Based Contracts: A Good Option To Address Long-Term Road Maintenance In California?, Maria Calahorra-Jimenez, Richard Poythress

Mineta Transportation Institute

Performance-based contracts (PBCs) used in road maintenance provide flexibility for considering new materials, design, and technology to achieve predetermined performance targets. Several states in the U.S. have already used these types of contracts in road maintenance, and their experience can inform the use of PBCs in California. The objectives of this research are twofold. First, identify the benefits and challenges of PBCs compared to traditional contracts. Second, explore the main aspects of PBCs implementation for road maintenance and relate them to California's context. To this end, deductive-inductive content analysis was conducted on 84 peer-reviewed articles published between 1998 and 2023. …


Smart Robot Design And Implementation To Assist Pedestrian Road Crossing, Hovannes Kulhandjian Jun 2024

Smart Robot Design And Implementation To Assist Pedestrian Road Crossing, Hovannes Kulhandjian

Mineta Transportation Institute

This research focuses on designing and developing a smart robot to assist pedestrians with road crossings. Pedestrian safety is a major concern, as highlighted by the high annual rates of fatalities and injuries. In 2020, the United States recorded 6,516 pedestrian fatalities and approximately 55,000 injuries, with children under 16 being especially vulnerable. This project aims to address this need by offering an innovative solution that prioritizes real-time detection and intelligent decision-making at intersections. Unlike existing studies that rely on traffic light infrastructure, our approach accurately identifies both vehicles and pedestrians at intersections, creating a comprehensive safety system. Our strategy …


Impervious Surfaces From High Resolution Aerial Imagery: Cities In Fresno County, Yushin Ahn, Richard Poythress May 2024

Impervious Surfaces From High Resolution Aerial Imagery: Cities In Fresno County, Yushin Ahn, Richard Poythress

Mineta Transportation Institute

This study investigates impervious surfaces — areas covered by materials with restricted water permeability, such as pavement, sidewalks, and parking lots—due to their crucial role in influencing water dynamics within urban landscapes. The impermeability of these surfaces disrupts natural water absorption processes, resulting in adverse environmental consequences such as increased flooding, erosion, and water pollution. The research employs impervious surface analysis, a method involving the mapping and analysis of these surfaces within specified study areas, including cities, counties, and census tracts. Remote sensing techniques, specifically satellites and aerial imagery, are commonly utilized for the identification and classification of impervious surfaces. …


Does California High-Speed Rail Promote Accessibility For Station Cities?: Case Study Of Fresno And Merced, Chih-Hao Wang, Na Chen May 2024

Does California High-Speed Rail Promote Accessibility For Station Cities?: Case Study Of Fresno And Merced, Chih-Hao Wang, Na Chen

Mineta Transportation Institute

California High-Speed Rail (CHSR) will largely change transportation cost across the state after it starts operating. Past studies show that only Fresno and Merced among station cities in the Central Valley would attract more future activities with the CHSR. The establishment of active CHSR also implies a new daily living sphere for all the station cities, and, therefore, accessibility to work and residential amenities should be reviewed to inform planners of future land-use and transportation developments. A research framework has been developed better to understand the impact of CHSR on job and amenity accessibility by driving, transit, and walking in …


Investigating The Effects Of Alcohol Consumption On Manual And Automated Driving: A Systematic Review, Miaomiao Dong, Yuni Lee, Jackie Cha, Gaojian Huang Feb 2024

Investigating The Effects Of Alcohol Consumption On Manual And Automated Driving: A Systematic Review, Miaomiao Dong, Yuni Lee, Jackie Cha, Gaojian Huang

Mineta Transportation Institute

There are direct correlations between drunk driving and car-related injuries, disabilities, and death. Autonomous vehicles (AVs) may provide useful driver support systems to prevent or reduce road accidents. However, AVs are not yet fully automated and require human drivers to take over the vehicle at times. Therefore, understanding how alcohol affects driving performance in both manual and automated driving is important because manual drives may offer insights into the takeover process in AVs. A systematic review of 53 articles from eight databases was conducted. Findings were categorized based on the human information processing model, which can be extended to the …


Beneath I-280: Excavating A Neighborhood Lost To San José Freeways, Leila Ullmann, Gordon Douglas Feb 2024

Beneath I-280: Excavating A Neighborhood Lost To San José Freeways, Leila Ullmann, Gordon Douglas

Mineta Transportation Institute

Throughout the 1960s and 1970s, thousands of people in San José, California were displaced from their homes as the state used eminent domain to purchase land and uproot neighborhoods for the construction of Interstate freeways. This report presents a multifaceted research and public knowledge effort that uncovers some of the communities buried beneath these freeways, in the area where I-280 and CA-87 meet today near downtown San José. The project builds primarily from previously unprocessed California Department of Transportation (CalTrans) archival documents, which this project studies for the first time. The records are rich in detail about valuation and sale …


A Practical Framework For Component-Level Structural Health Monitoring Of The Gerald Desmond Bridge, Mehran Rahmani, Vesna Terzic, Andrea Calabrese, Brittany Cambell Jan 2024

A Practical Framework For Component-Level Structural Health Monitoring Of The Gerald Desmond Bridge, Mehran Rahmani, Vesna Terzic, Andrea Calabrese, Brittany Cambell

Mineta Transportation Institute

Bridges serve as critical transportation infrastructure, but traditional maintenance inspection to ensure their safety is time-consuming, costly, and labor-intensive, especially for larger and more complex structures. This study presents a practical framework for the instrumentation, data acquisition, and remote condition assessment of the Gerald Desmond Bridge, California’s largest cable-stayed bridge. The framework aims to establish a foundation for real-time or near real-time remote health monitoring of the bridge’s critical elements. The study highlights the advantages of remote monitoring in terms of efficiency, cost-effectiveness, and early detection of damage.


Examining The Externalities Of Highway Capacity Expansions In California: An Analysis Of Land Use And Land Cover (Lulc) Using Remote Sensing Technology, Serena E. Alexander, Bo Yang, Owen Hussey, Derek Hicks Nov 2023

Examining The Externalities Of Highway Capacity Expansions In California: An Analysis Of Land Use And Land Cover (Lulc) Using Remote Sensing Technology, Serena E. Alexander, Bo Yang, Owen Hussey, Derek Hicks

Mineta Transportation Institute

There are over 590,000 bridges dispersed across the roadway network that stretches across the United States alone. Each bridge with a length of 20 feet or greater must be inspected at least once every 24 months, according to the Federal Highway Act (FHWA) of 1968. This research developed an artificial intelligence (AI)-based framework for bridge and road inspection using drones with multiple sensors collecting capabilities. It is not sufficient to conduct inspections of bridges and roads using cameras alone, so the research team utilized an infrared (IR) camera along with a high-resolution optical camera. In many instances, the IR camera …


Fiber-Based Seismic Damage And Collapse Assessment Of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Indices, Yu-Fu Ko, Jessica Gonzalez Aug 2023

Fiber-Based Seismic Damage And Collapse Assessment Of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Indices, Yu-Fu Ko, Jessica Gonzalez

Mineta Transportation Institute

Near-fault earthquakes can have major effects on transportation systems due to the structural damage they impose on bridges. Therefore, it is imperative to assess the seismic damage of bridges appropriately, and this research focuses on reinforced concrete (RC) bridges. This research advances the seismic performance assessment of RC single-column pier-supported bridges with flexural failure under near-fault ground motion by use of ductility coefficients and damage indices. The methodology included modeling fiber-based nonlinear beam-column elements to simulate the damage development process of RC bridge piers under earthquake loadings, considering the global buckling of longitudinal steel bars, examining the cracking and spalling …


System-Of-Systems Integration For Civil Infrastructures Resiliency Toward Multihazard Events, Vahid Balali Aug 2023

System-Of-Systems Integration For Civil Infrastructures Resiliency Toward Multihazard Events, Vahid Balali

Mineta Transportation Institute

Civil infrastructure systems—facilities that supply principal services, such as electricity, water, transportation, etc., to a community—are the backbone of modern society. These systems are frequently subject to multi-hazard events, such as earthquakes. The poor resiliency of these infrastructures results in many human casualties and significant economic losses every year. An outline of a holistic view that considers how different civil infrastructure systems operate independently and how they interact and communicate with each other is required to have a resilient infrastructure system. More specifically a systems engineering approach is required to enable infrastructure to remain resilient in the case of extreme …


Electrical Vehicle Charging Infrastructure Design And Operations, Yu Yang, Hen-Geul Yeh Jul 2023

Electrical Vehicle Charging Infrastructure Design And Operations, Yu Yang, Hen-Geul Yeh

Mineta Transportation Institute

California aims to achieve five million zero-emission vehicles (ZEVs) on the road by 2030 and 250,000 electrical vehicle (EV) charging stations by 2025. To reduce barriers in this process, the research team developed a simulation-based system for EV charging infrastructure design and operations. The increasing power demand due to the growing EV market requires advanced charging infrastructures and operating strategies. This study will deliver two modules in charging station design and operations, including a vehicle charging schedule and an infrastructure planning module for the solar-powered charging station. The objectives are to increase customers’ satisfaction, reduce the power grid burden, and …


Extending The Service-Life Of Bridges Using Sustainable And Resilient Abutment Systems: An Experimental Approach To Electrochemical Characterization Of Lightweight Mechanically Stabilized Earth, Fariborz M. Tehrani, Kenneth L. Fishman, Farmehr M. Dehkordi Jul 2023

Extending The Service-Life Of Bridges Using Sustainable And Resilient Abutment Systems: An Experimental Approach To Electrochemical Characterization Of Lightweight Mechanically Stabilized Earth, Fariborz M. Tehrani, Kenneth L. Fishman, Farmehr M. Dehkordi

Mineta Transportation Institute

Bridges are critical components of transportation infrastructure. This research addresses the need to extend the service life of bridges by improving the safety and reliability of bridge abutments and reducing their life-cycle cost and footprints. Mechanically stabilized earth (MSE) is a known strategy to enhance the economy and performance of bridge abutments. In addition, the application of rotary-kiln-manufactured lightweight aggregate backfills improves the performance of MSE bridge abutments with a leaner structural system. Such improvements include a reduction of structural demands due to a lower density, free drainage of granular materials, a high internal friction angle, less settlement with no …


Pavement Condition Survey Using Drone Technology, Lerose Lane, Dingxin Cheng Jun 2023

Pavement Condition Survey Using Drone Technology, Lerose Lane, Dingxin Cheng

Mineta Transportation Institute

Timely repairs of pavement defects are essential in protecting both public road and highway systems. Identification of pavement distresses is necessary for planning pavement repairs. This has previously been performed by engineers surveying the roadways visually in the field. As drone usage has progressed, it has become clear that drones are a valuable tool to enhance visual documentation, improve project communication, and provide various data for processing. The use of drone technology has improved both the speed and accuracy of capturing data. Available software has allowed the data to be processed and analyzed in an office environment. This report summarizes …


Smart Transportation In Small- And Medium-Sized Cities In Central California, Hongwei Dong May 2023

Smart Transportation In Small- And Medium-Sized Cities In Central California, Hongwei Dong

Mineta Transportation Institute

The research on smart transportation in the United States has centered on large metropolitan areas. The adoption of smart transportation technologies in small-and medium-sized cities outside of large metropolitan areas is less studied and understood. This study examined the adoption of smart transportation technologies in small-and medium-sized cities in Central California. The analysis was based on the online survey responses from 29 transportation officials and professionals who worked for 18 municipal government departments and six metropolitan planning organizations (MPOs) in Central California as well as in depth semi-structured interviews with seven of them. The study showed that smart transportation in …


Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos May 2023

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos

Mineta Transportation Institute

Although concrete is the most widely used building material in the world, its limited tensile strength makes cracking a common phenomenon in concrete elements. This study investigates the potential of autonomous self-healing as an eco-friendly and lowcost method to increase the durability of concrete. The crack-healing potential of different types of high-alkaline-tolerant bacteria or calcite-precipitation microorganisms is investigated. High-alkaline-tolerant bacteria and calcite-precipitation microorganisms were used to retrofit lab-fractured concrete samples. The samples healed with each of these bacteria groups were cast and tested under compressive load up to failure to measure the compressive strength of the concrete samples. The outcomes …


Preconstruction Support Cost Hours Estimating On Caltrans Pavement Rehabilitation Projects, Nigel Blampied, Tariq Shehab, Elhami Nasr, Laxmi Sindhu Samudrala May 2023

Preconstruction Support Cost Hours Estimating On Caltrans Pavement Rehabilitation Projects, Nigel Blampied, Tariq Shehab, Elhami Nasr, Laxmi Sindhu Samudrala

Mineta Transportation Institute

Because the construction phase accounts for the majority of project costs for pavement rehabilitation projects, most research on infrastructure project cost estimating focuses on that phase, rather than on the preconstruction phases. Nevertheless, costs incurred prior to construction, referred to in this report as "preconstruction costs" are significant and worthy of consideration (See Section 2.1 of the report for a more detailed and precise definition of preconstruction). In the 20202021 fiscal year, for instance, the California Department of Transportation (Caltrans) spent more than $169 million on preconstruction work for pavement rehabilitation projects. This report presents the results of a study …


Modeling And Evaluating Alternatives To Enhance Access To An Airport And Meet Future Expansion Needs, Srinivas S. Pulugurtha, Abimbola Ogungbire, Chirag Akbari Apr 2023

Modeling And Evaluating Alternatives To Enhance Access To An Airport And Meet Future Expansion Needs, Srinivas S. Pulugurtha, Abimbola Ogungbire, Chirag Akbari

Mineta Transportation Institute

The continued growth of air travel calls for the incessant construction effort at many airports and their surroundings. Thus, there is a need to determine how airports can better manage existing infrastructure to accommodate this growth. This study, therefore, focuses on (1) investigating how changes in transportation infrastructure have affected travel time reliability (TTR) of the surrounding road network within the airport vicinity over time, and, (2) exploring selected unconventional intersection designs and proposing new inbound/outbound access routes from the nearby major roads to the airport. The efficiency of road networks that surrounds large airports is discussed using Charlotte Douglas …


Using Thermal Remote Sensing To Quantify Impact Of Traffic On Urban Heat Islands During Covid, My-Thu Tran, Bo Yang Apr 2023

Using Thermal Remote Sensing To Quantify Impact Of Traffic On Urban Heat Islands During Covid, My-Thu Tran, Bo Yang

Mineta Transportation Institute

A three-month lockdown in the U.S. at the beginning of the COVID-19 outbreak in 2020 greatly reduced the traffic volume in many cities, especially large metropolitan areas such as the San Francisco Bay Area. This research explores the impact of transportation on climate change by using remote sensing technology and statistical analysis during the COVID-19 lockdown. Using thermal satellite data, this research measures the intensity of the urban heat island, the main driver for climate change during the urbanization process. The research team acquired morning and afternoon MODIS data in the same periods in 2019 before the pandemic and 2020 …


Evaluating Automated Truck Platoon (Atp) Deployment For The Los Angeles–Inland Empire Trade Corridor Enhancement, Shailesh Chandra, Aastha Chaudhary, Prakhar Srivastava, Jose Torres-Aguilera Mar 2023

Evaluating Automated Truck Platoon (Atp) Deployment For The Los Angeles–Inland Empire Trade Corridor Enhancement, Shailesh Chandra, Aastha Chaudhary, Prakhar Srivastava, Jose Torres-Aguilera

Mineta Transportation Institute

The California Freight Mobility Plan 2020 lists the Los Angeles-Inland Empire trade corridor region as a prominent industrial hub experiencing an increase in freight flows. The California Freight Mobility Plan also regards automated truck platoon (ATP) as an emerging opportunity to minimize congestion on the trade corridor routes. Percentage change in accessibility from 2022 (“without” ATP) to 2040 (“with” ATP) is calculated for the eighteen industry sectors of the Los Angeles-Inland Empire trade corridor. The application of the accessibility formulation was carried out with data on travel time from I-710 and I-10 within Los Angeles County. The findings suggest that …


Evaluation, Comparison, And Improvement Recommendations For Caltrans Financial Programming Processes And Tools, Wenbin Wei, Nigel Blampied, Raajmaathangi Sreevijay Feb 2023

Evaluation, Comparison, And Improvement Recommendations For Caltrans Financial Programming Processes And Tools, Wenbin Wei, Nigel Blampied, Raajmaathangi Sreevijay

Mineta Transportation Institute

The California Transportation Improvement Program System (CTIPS) is the main tool used by Caltrans’ Division of Financial Programming to support the business of transportation programming. It is a multi-agency joint-use project programming database system applied to develop and manage various state and federal transportation programming documents. The goal of this project is to evaluate CTIPS and explore various new options that will maintain the current functionality of CTIPS, meet legislative guidelines for ADA compliance, ensure security of the system, and have sufficient scalability and capabilities for integration with other systems in the future. The research is based on the review …


Evaluation Of Nanoclay Additives For Improving Resistance To Moisture Damage In Hot Mix Asphalt (Hma), Amro El Badawy, Ashraf Rahim Jan 2023

Evaluation Of Nanoclay Additives For Improving Resistance To Moisture Damage In Hot Mix Asphalt (Hma), Amro El Badawy, Ashraf Rahim

Mineta Transportation Institute

Transportation has an enormous impact on the U.S. economy and on the lives of all Americans. Many modes of transportation rely on pavement, but pavement conditions deteriorate over time because of the combined effects of traffic and climate. Exposure to moisture often causes premature failure of asphalt pavements as it reduces the stiffness of the asphalt and enables stripping of the asphalt from the aggregate. This research evaluates the effectiveness of clay nanomaterials (i.e., nanoclays) in improving the resistance of hot mix asphalt (HMA) to moisture damage and compares the enhancement results to anti-stripping additives commonly used in pavement construction. …


Evaluation Of Left Shoulder As Part-Time Travel Lane Design Alternatives And Transportation Management Center Staff Training Module Development, Zhuohang Deng, Zhiliang Luo, Neil Hockaday, Ahmed Farid, Anurag Pande Jan 2023

Evaluation Of Left Shoulder As Part-Time Travel Lane Design Alternatives And Transportation Management Center Staff Training Module Development, Zhuohang Deng, Zhiliang Luo, Neil Hockaday, Ahmed Farid, Anurag Pande

Mineta Transportation Institute

Permanent capacity expansion, such as adding new lanes, is no longer a viable strategy to address traffic congestion in California; hence, ITS (Intelligent Transportation System) strategies, such as part-time use of the shoulder as a travel lane, need to be explored. The use of the shoulder as a travel lane during peak traffic hours has limited applications in the US, and most use the right shoulder as a part-time travel lane even though either the right or left shoulder (but not both) may be used. Caltrans District 5 is exploring the use of Left Shoulder as a Part-time Travel Lane …


Effect Of Weather Events On Travel Time Reliability And Crash Occurrence, Sonu Mathew, Srinivas S. Pulugurtha Nov 2022

Effect Of Weather Events On Travel Time Reliability And Crash Occurrence, Sonu Mathew, Srinivas S. Pulugurtha

Mineta Transportation Institute

The magnitude of the effect of adverse weather conditions on road operational performance varies with the type of weather condition and the road characteristics of the road links and adjacent links. Therefore, the relationship between weather and traffic is always a concern to traffic engineers and planners, and they have extensively explored ways to integrate weather information into transportation systems. Understanding the influence of weather on operational performance and safety helps traffic engineers and planners to proactively plan and manage transportation systems. The main objective of this research is to evaluate the effect of adverse weather conditions on travel time …


Does Transit Service Reliability Influence Ridership?, Srinivas S. Pulugurtha, Raunak Mishra, Sravya L. Jayanthi Nov 2022

Does Transit Service Reliability Influence Ridership?, Srinivas S. Pulugurtha, Raunak Mishra, Sravya L. Jayanthi

Mineta Transportation Institute

This research focused on analyzing the association between transit service reliability indicators and ridership. Further, the effect of road network, demographic, socioeconomic, and land use characteristics on transit service reliability was analyzed. The analysis was conducted at a bus stop level. Bus arrival/departure and ridership data from the Charlotte Area Transit System (CATS) was obtained. The road network, demographic, socioeconomic, and land use characteristics were captured within 0.25-mile and 0.50-mile buffers. Pearson correlation analysis was conducted to understand the association between road network, demographic, socioeconomic, and land use characteristics and bus transit service reliability measures. The results show that bus …


Exploring The Effects Of Meaningful Tactile Display On Perception And Preference In Automated Vehicles, Kimberly D. Martinez, Gaojian Huang Oct 2022

Exploring The Effects Of Meaningful Tactile Display On Perception And Preference In Automated Vehicles, Kimberly D. Martinez, Gaojian Huang

Mineta Transportation Institute

There is an existing issue in human-machine interaction, such that drivers of semi-autonomous vehicles are still required to take over control of the vehicle during system limitations. A possible solution may lie in tactile displays, which can present status, direction, and position information while avoiding sensory (e.g., visual and auditory) channels overload to reliably help drivers make timely decisions and execute actions to successfully take over. However, limited work has investigated the effects of meaningful tactile signals on takeover performance. This study synthesizes literature investigating the effects of tactile displays on takeover performance in automated vehicles and conducts a human-subject …


Understanding The Safety And Usability Of Personal Vehicles For Non-Driving Individuals With Disabilities And Their Families/Care Providers, Anil R. Kumar, Hannah Bowman Oct 2022

Understanding The Safety And Usability Of Personal Vehicles For Non-Driving Individuals With Disabilities And Their Families/Care Providers, Anil R. Kumar, Hannah Bowman

Mineta Transportation Institute

The connections between shared personal vehicles of individuals with disabilities (IWDs) and their household family members play an important role in the mobility, overall health, and well-being of all involved actors, yet this topic remains mostly overlooked within publicly available research. Families that include a non-driving IWD are more likely to be low-income, and often struggle with the costs of operating a family car but, due to insufficient public transportation options, they own vehicles despite their prohibitive cost. This exploratory study utilized the Systems Engineering Initiative for Patient Safety (SEIPS) model, a framework focused on assessing the interplaying sociotechnical factors …