Matching Items (19)
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- All Subjects: Transportation
- All Subjects: STEM
- Creators: Zhou, Xuesong
- Creators: Civil, Environmental and Sustainable Eng Program
Description
Automated vehicles are becoming more prevalent in the modern world. Using platoons of automated vehicles can have numerous benefits including increasing the safety of drivers as well as streamlining roadway operations. How individual automated vehicles within a platoon react to each other is essential to creating an efficient method of travel. This paper looks at two individual vehicles forming a platoon and tracks the time headway between the two. Several speed profiles are explored for the following vehicle including a triangular and trapezoidal speed profile. It is discovered that a safety violation occurs during platoon formation where the desired time headway between the vehicles is violated. The aim of this research is to explore if this violation can be eliminated or reduced through utilization of different speed profiles.
ContributorsLarson, Kurt Gregory (Author) / Lou, Yingyan (Thesis director) / Chen, Yan (Committee member) / Civil, Environmental and Sustainable Eng Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Recurring incidents between pedestrians, bicycles, and vehicles at the intersection of Rural Road and Spence Avenue led to a team of students conducting their own investigation into the current conditions and analyzing a handful of alternatives. An extension of an industry-standard technique was used to build a control case which alternatives would be compared to. Four alternatives were identified, and the two that could be modeled in simulation software were both found to be technically feasible in the preliminary analysis.
ContributorsFellows, Christopher Lee (Author) / Lou, Yingyan (Thesis director) / Zhou, Xuesong (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Approximately 1% of the total working population within the United States bikes as their primary mode of commute. Due to recent increased in bicycle facilities as well as a focus on alternative modes of transport, understanding the motivations and type of people who bike to work is important in order to encourage new users.
In this project, a literature review was completed as well as data analysis of the National Household Travel Survey (NHTS) in order to find specific populations to target. Using these target populations, it is suggested that advertising and workplace encouragement occur to persuade more people to bike to work. Through data analysis it was found that the most impactful variables were the region of the country, gender, population density, and commute distance. Bicycle commuters statistically had fewer vehicles in their households and drove less miles annually.
There were five main target groups found through this analysis; people who bike for other reasons besides work and live in a city with more than 4,000 people per square mile, young professionals between 19-39, women in regions with separated bicycle facilities, those with low vehicle availability, and environmentally conscious individuals. Working to target these groups through advertising campaigns to encourage new users, as well as increasing and improving bicycle facilities, will help create more new bicyclists.
In this project, a literature review was completed as well as data analysis of the National Household Travel Survey (NHTS) in order to find specific populations to target. Using these target populations, it is suggested that advertising and workplace encouragement occur to persuade more people to bike to work. Through data analysis it was found that the most impactful variables were the region of the country, gender, population density, and commute distance. Bicycle commuters statistically had fewer vehicles in their households and drove less miles annually.
There were five main target groups found through this analysis; people who bike for other reasons besides work and live in a city with more than 4,000 people per square mile, young professionals between 19-39, women in regions with separated bicycle facilities, those with low vehicle availability, and environmentally conscious individuals. Working to target these groups through advertising campaigns to encourage new users, as well as increasing and improving bicycle facilities, will help create more new bicyclists.
ContributorsImbus, Eileen Elizabeth (Author) / Khoeini, Sara (Thesis director) / Pendyala, Ram (Committee member) / Civil, Environmental and Sustainable Eng Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Gathering the necessary information required to tackle traffic congestion problems is generally time consuming and challenging but is an important part of city planners’ work. The purpose of this paper is to describe the methodology used when analyzing potential solutions for the Arizona State Route 89A and Highway 179 roundabout in Sedona, Arizona; which is currently experiencing significant congestion. The oversaturated condition is typically applied to signalized intersections but its application to roundabouts requires further exploration for future management of similar transportation systems. The accompanying Quick Estimation and Simulation model (QESM) spreadsheet was calibrated using an iterative process to optimize its level of adaptability to various scenarios. This microsimulation modeling program can be used to predict the outcome of possible roadway improvements aimed at decreasing traffic congestion. The information provided in this paper helps users understand traffic system problems, as a primary to visual simulation programs.
ContributorsBrunetti, Isabel (Co-author) / Tran, Adam (Co-author) / Zhou, Xuesong (Thesis director) / Carreon, Adam (Committee member) / Civil, Environmental and Sustainable Eng Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Minority women continue to be underrepresented in STEM fields and in STEM related degrees, leading to a lack of diversity in the research conducted and voices advocated for in STEM. To understand why there continues to be a lack of representation of minority women in STEM, I conducted a survey of approximately 20 high school girls who identified as minorities and had an interest in science and conservation to ask questions about their hesitancy to attend college and the different barriers they face. The results of this survey show that these minority girls have low hesitancy when considering applying to and attending college. The biggest barrier these girls face is cost, with 74% of respondents citing college expense as a source of hesitancy when considering applying to college. I then discuss possible interventions that would lead to an increase in the representation of minority women in STEM in higher education. I suggest that colleges and universities should highlight scholarships, financial aid, and programs available and that minority women are eligible for, or they should reduce the cost of tuition.
ContributorsClark, Amelie (Author) / Iacona, Gwen (Thesis director) / Gerber, Leah (Committee member) / Bisgrove, Daniel (Committee member) / Barrett, The Honors College (Contributor) / Civil, Environmental and Sustainable Eng Program (Contributor)
Created2023-12
Description
The emerging multimodal mobility as a service (MaaS) and connected and automated mobility (CAM) are expected to improve individual travel experience and entire transportation system performance in various aspects, such as convenience, safety, and reliability. There have been extensive efforts in the literature devoted to enhancing existing and developing new methodologies and tools to investigate the impacts and potentials of CAM systems. Due to the hierarchical nature of CAM systems and associated intrinsic correlated human factors and physical infrastructures from various resolutions, simply considering components across different levels into a single model may be practically infeasible and computationally prohibitive in operation and decision stages. One of the greatest challenges in existing studies is to construct a theoretically sound and computationally efficient architecture such that CAM system modeling can be performed in an inherently consistent cross-resolution manner. This research aims to contribute to the modeling of CAM systems on layered transportation networks, with a special focus on the following three aspects: (1) layered CAM system architecture with a tight network and modeling consistency, in which different levels of tasks can be efficiently performed at dedicated layers; (2) cross-resolution traffic state estimation in CAM systems using heterogeneous observations; and (3) integrated city logistics operation optimization in CAM for improving system performance.
ContributorsLu, Jiawei (Author) / Zhou, Xuesong (Thesis advisor) / Pendyala, Ram (Committee member) / Xue, Guoliang (Committee member) / Mittelmann, Hans (Committee member) / Arizona State University (Publisher)
Created2022
Description
This report attempts to understand the effects of the many aspects that pertain to a woman’s path into the construction industry and their role in limiting women’s overall representation in the construction industry. More specifically, it aims to understand how upbringing, background, and culture impact women that do pursue careers in the construction industry. This paper presents some of the current and prominent issues being faced by women in in the construction industry, including those in the trades. These issues then contribute to their lack of representation and forceful exit. Additionally, it assesses personal narratives from a localized group of women who are currently employed at a large construction company. This information and these narratives are analyzed jointly to try and gain a better understanding of the current challenges being faced by women in comparison to those reported previously. This joint comparison allows for a deeper understanding of women’s perception of the construction industry as a whole.
ContributorsContreras, Marisa (Author) / Lou, Yingyan (Thesis director) / Parrish, Kristen (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Social Transformation (Contributor) / Civil, Environmental and Sustainable Eng Program (Contributor)
Created2022-05
Description
This podcast focused on the experience of women in the field of STEM and more specifically civil engineering. The episodes will explore three main topics surrounding women in the workforce: how women navigate and succeed in a workforce with a predominantly male presence, whether or not women experience “impostor syndrome”, and how to deal with being undermined in the workforce. Also available on Spotify! https://open.spotify.com/show/6iyemJ08Et4JCEATtlgNls?si=03167fd008e94bb6
ContributorsRivera, Valentina (Author) / DiCaro, Isabella (Co-author) / Hjelsmtad, Keith (Thesis director) / Boyce-Jacino, Katherine (Committee member) / Barrett, The Honors College (Contributor) / Civil, Environmental and Sustainable Eng Program (Contributor)
Created2022-05
Description
In this dissertation, a cyber-physical system called MIDAS (Managing Interacting Demand And Supply) has been developed, where the “supply” refers to the transportation infrastructure including traffic controls while the “demand” refers to its dynamic traffic loads. The strength of MIDAS lies in its ability to proactively control and manage mixed vehicular traffic, having various levels of autonomy, through traffic intersections. Using real-time traffic control algorithms MIDAS minimizes wait times, congestion, and travel times on existing roadways. For traffic engineers, efficient control of complicated traffic movements used at diamond interchanges (DI), which interface streets with freeways, is challenging for normal human driven vehicular traffic, let alone for communicationally-connected vehicles (CVs) due to stochastic demand and uncertainties. This dissertation first develops a proactive traffic control algorithm, MIDAS, using forward-recursion dynamic programming (DP), for scheduling large set of traffic movements of non-connected vehicles and CVs at the DIs, over a finite-time horizon. MIDAS captures measurements from fixed detectors and captures Lagrangian measurements from CVs, to estimate link travel times, arrival times and turning movements. Simulation study shows MIDAS’ outperforms (a) a current optimal state-of-art optimal fixed-cycle time control scheme, and (b) a state-of-art traffic adaptive cycle-free scheme.
Subsequently, this dissertation addresses the challenges of improving the road capacity by platooning fully autonomous vehicles (AVs), resulting in smaller headways and greater road utilization. With the MIDAS AI (Autonomous Intersection) control, an effective platooning strategy is developed, and optimal release sequence of AVs is determined using a new forward-recursive DP that minimizes the time-loss delays of AVs. MIDAS AI evaluates the DP decisions every second and communicates optimal actions to the AVs.
Although MIDAS AI’s exact DP achieves optimal solution in almost real-time compared to other exact algorithms, it suffers from scalability. To address this challenge, the dissertation then develops MIDAS RAIC (Reinforced Autonomous Intersection Control), a deep reinforcement learning based real-time dynamic traffic control system for AVs at an intersection. Simulation results show the proposed deep Q-learning architecture trains MIDAS RAIC to learn a near-optimal policy that minimizes the total cumulative time loss delay and performs nearly as well as the MIDAS AI.
ContributorsPotluri, Viswanath (Author) / Mirchandani, Pitu (Thesis advisor) / Ju, Feng (Committee member) / Zhou, Xuesong (Committee member) / Sefair, Jorge (Committee member) / Arizona State University (Publisher)
Created2023
Description
The goal of this creative thesis is to focus on the experience of women in the field of STEM and more specifically civil engineering. This project will explore four main topics surrounding women in the workforce: how women navigate and succeed in a workforce with predominant male presence, how women advance their career given the gender barriers of the industry, including motherhood, and “impostor syndrome” in the workforce
ContributorsDiCaro, Isabella (Author) / Rivera, Valentina (Abridger) / Boyce-Jacino, Katherine (Thesis director) / Hjelmstad, Keith (Committee member) / Barrett, The Honors College (Contributor) / Civil, Environmental and Sustainable Eng Program (Contributor)
Created2022-05