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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

A Stated Preference Study for Assessing Public Acceptance Towards Autonomous Vehicles

Christos Gkartzonikas (5929697) 29 April 2020 (has links)
<div>Technology is rapidly transforming both vehicles and transportation systems. The nature of this transformation will depend on how fast the technology resulting from three related revolutions, those in automated, electric, and shared vehicles, will diffuse. At the same time, the ‘sharing’ economy is growing and affecting mobility in urban areas that includes additional travel alternatives, such as car-sharing services, ride-hailing services, bike-sharing services, and other micro-transit services. It is evident that to prepare for these large-scale operations involving autonomous vehicles (AVs), researchers and transportation professionals need the useful insights on people’s attitudes toward and on acceptance of AVs that can be gained through behavioral experiments. In addition to this, it is also important to understand how the deployment of AVs will impact vehicle ownership and mode choice decisions.</div><div><br></div><div>The goal of this dissertation is to assess the public acceptance of AVs and shared autonomous vehicles (SAVs) via a behavioral experiment (stated preference survey) and offer insights on the potential implications of AVs and SAVs on mode choices. The following four overarching research objectives were formulated: (a) identifying the factors influencing the behavioral intention to ride in AVs; (b) identifying the characteristics of the AV market segments; (c) evaluating the attributes impacting personal vehicle ownership decisions (i.e., decisions to postpone the purchase of a non-AV due to the emergence of AVs); and (d) assessing the factors affecting mode choice decisions after the emergence of autonomous ride-sharing services operated through AVs, and evaluating the corresponding value of travel time savings. The results of each part of the research framework are integrated in the last chapter of the dissertation in order to provide the final conclusions and recommendations of the study.</div><div><br></div><div>To achieve these research objectives, a survey of the general population was distributed online in a major urban area with an advanced multimodal transportation system and captive users of ride-sharing users (Chicago, Illinois) and in an urban area with a more automobile-oriented culture (Indianapolis, Indiana). The survey sample included 400 responses of adults, representative of age and gender on each area. </div><div><br></div><div>One of the contributions of this dissertation is a theoretical model to assess the behavioral intention to ride in AVs that includes components of the theory of Planned Behavior, the theory of Diffusion of Innovation and additional factors derived from the literature while evaluating possible interrelationships between these components. A more holistic approach along these lines can help explain whether the emerging AV technology can diffuse by identifying the factors and key determinants that influence the behavioral intention to ride in AVs. The market segmentation analysis can further provide knowledge of the socio-demographic characteristics of potential AV users and an accurate classification of these groups of potential users in terms of their willingness to ride in AVs. The findings can provide insights into perceptions of and attitudes toward AVs that can help transportation and urban planners, as well as original equipment manufacturers, to prepare for the deployment of AVs by designing marketing strategies to improve people’s perceptions of AVs and increase market penetration.</div><div><br></div><div>Moreover, this dissertation provides a well-documented and easy-to-use framework that can support both planning and policy decisions in urban areas in an era of emergent automated transportation technologies. In urban areas with advanced multimodal transportation networks, the framework can be applied to identify the impact attributes affecting shared mobility in urban settings. In urban areas with a more car-oriented culture, the framework can be applied to explore the potential impacts of the emergence of AVs on personal vehicle ownership patterns. Finally, the survey that was designed to fulfill the goal of this dissertation can be replicated and distributed in metropolitan areas outside the US with more advanced multimodal transportation systems or areas within the US with traditionally higher rates of affinity to innovativeness and areas where AVs have been pilot-tested in real-world road conditions.</div><div><br></div>
282

Unmanned Aerial Vehicle Remote Sensing of Soil Moisture with I-Band Signals of Opportunity

Jared D Covert (8816072) 08 May 2020 (has links)
Measurements of root zone soil moisture play large roles in our understanding of the water cycle, weather, climate, land-heat exchanges, drought forecasting, and agriculture. Current measurements are made using a combination of ground-based sampling and active and passive microwave remote sensing. Signals of Opportunity (SoOp) has emerged as a promising method for sensing soil moisture, using satellite communication signals to make bi-static reflectometry measurements. The current combination of ground and satellite-based measurements for soil moisture results in a gap of useful spatial and temporal resolutions, as well as limited soil penetration depth. This thesis developed and constructed an Unmanned Aerial Vehicle (UAV) mountable, I-band SoOp instrument with calibration capabilities, along with supporting specular point mapping and mission planning software. This work advances the creation of a compact, mobile, root zone soil moisture (RZSM) remote sensing system.
283

Lidská perspektiva k etice strojů / Human Perspectives on Machine Ethics

Tomalová, Kateřina January 2018 (has links)
This diploma thesis deals with roboethics and its associated moral and social dilemmas. The theoretical part of this thesis defines roboethics and presents the diverse opinions and approaches, deals with the position of robots in society and also subsequently examines the various problematic areas of the use of robots. The conclusion of the theoretical part of the thesis then focuses on autonomous vehicles, to which the quantitative and qualitative research parts of the thesis are devoted. The research part of this diploma thesis aims to find out the opinions on this issue of the Czech general public and Czech experts as well as to find out whether their opinions are aligned, how their opinions differ and lastly, which issues are the most important for the future development of this field.
284

Localization of autonomous ground vehicles in dense urban environments

Himstedt, Marian 25 January 2011 (has links)
The localization of autonomous ground vehicles in dense urban environments poses a challenge. Applications in classical outdoor robotics rely on the availability of GPS systems in order to estimate the position. However, the presence of complex building structures in dense urban environments hampers a reliable localization based on GPS. Alternative approaches have to be applied In order to tackle this problem. This thesis proposes an approach which combines observations of a single perspective camera and odometry in a probabilistic framework. In particular, the localization in the space of appearance is addressed. First, a topological map of reference places in the environment is built. Each reference place is associated with a set of visual features. A feature selection is carried out in order to obtain distinctive reference places. The topological map is extended to a hybrid representation by the use of metric information from Geographic Information Systems (GIS) and satellite images. The localization is solved in terms of the recognition of reference places. A particle lter implementation incorporating this and the vehicle's odometry is presented. The proposed system is evaluated based on multiple experiments in exemplary urban environments characterized by high building structures and a multitude of dynamic objects.
285

Design of Mobility Cyber Range and Vision-Based Adversarial Attacks on Camera Sensors in Autonomous Vehicles

Ramayee, Harish Asokan January 2021 (has links)
No description available.
286

Out of sight, out of mind? : Assessing human attribution of object permanence capabilities to self-driving cars

Holmgren, Aksel January 2022 (has links)
Autonomous vehicles are regularly predicted to be on the verge of broad integration into regular traffic. A crucial aspect of successful traffic interactions is one agent’s ability to adequately understand other agents’ capabilities and limitations. Within the current state of the art concerning self-driving cars, there is a discrepancy between what people tend to believe the capabilities of self-driving cars are, and what those capabilities actually are. The aim of this study was to investigate whether people attribute the capacity of object permanence to self-driving cars roughly in the same manner as they would to a human driver. The study was conducted with online participants (N = 105). The results showed that the participants did not attribute object permanence differently between a self-driven car and a human driver. This indicates that people attribute object permanence similarly to self-driving cars as they do toward human drivers. Furthermore, the results indicate no connection between participants’ tendency to anthropomorphize and whether they attributed object permanence or not. The findings provide evidence for the issues connected to the perceptual belief problem in human-robot interaction, where people attribute capabilities to autonomous vehicles that are not there. The results highlight the importance of understanding which mechanisms underlie these attributions as well as when they happen, in order to mitigate unrealistic expectations.
287

Multi Time-Scale Hierarchical Control for Connected and Autonomous Vehicles

Boyle, Stephen January 2021 (has links)
No description available.
288

Strategic management of intellectual property in the field of vehicle autonomy and connectivity : A case study in the truck manufacturing field

Åkerblom, Philip January 2021 (has links)
The truck manufacturing field is expected to go through a disruptive change in the coming decade(s) due to a predicted implementation of autonomous (self-driving) heavy-duty vehicles. Here, companies face a challenge in that autonomous vehicles (AV) will include technologies and competences from multiple industries. This will most likely have an impact on how companies manage their intellectual property (IP) to protect their inventions if they wish to keep up with the changing market. To do this in the most optimal way, it is argued that a company’s IP-strategy needs to be incorporated into their business strategy. At the same time, studies show that companies are experiencing difficulties in extracting the full potential of their IP-management. Hence, this master thesis aims at investigating how a truck manufacturing company can adapt their IP-management policy in line with future developments within these emerging technologies and how their IP-strategy can become intertwined with their business strategy. Next to a literature review of these fields, the thesis conducts a qualitative case study of a truck manufacturer that intends to be part of this change based on 11 semi-structured interviews. From the empirical results, the company’s decision-making process regarding IP is identified, whereby this thesis suggests four points of improvement that could make their IP-management policy more effective. Further, this study presents three actions that can be taken in a company to incorporate their IP-strategy with their overall business strategy. The study ends with giving suggestions for future research and presenting six managerial implications that would come by implementing the suggestions made in this thesis.
289

VEHICLE AUTONOMY, CONNECTIVITY AND ELECTRIC PROPULSION: CONSEQUENCES ON HIGHWAY EXPENDITURES, REVENUES AND EQUITY

Chishala I Mwamba (11920535) 18 April 2022 (has links)
Asset managers continue to prepare physical infrastructure investments needed to accommodate the emerging technologies, namely vehicle connectivity, electrification, and automation. The provision of new infrastructure and modification of existing infrastructure is expected to incur a significant amount of capital investment. Secondly, with increasing EV and CAV operations, the revenues typically earned from vehicle registrations and fuel tax are expected to change due to changing demand for vehicle ownership and amount of travel, respectively. This research estimated (i) the changes in highway expenditures in an era of ECAV operations, (ii) the net change in highway revenues that can be expected to arise from ECAV operations, and (iii) the changes in user equity across the highway user groups (vehicle classes). In assessing the changes in highway expenditures, the research developed a model to predict the cost of highway infrastructure stewardship based on current and/ or future system usage. <div><br></div><div>The results of the research reveal that CAVs are expected to significantly change the travel patterns, leading to increased system usage which in turn results in increased wear and tear on highway infrastructure. This, with the need for new infrastructure to support and accommodate the new technologies is expected to result in increased highway expenditure. At the same time, CAVs are expected to have significantly improved fuel economy as compared to their human driven counterparts, leading to a decrease in fuel consumption per vehicle, resulting in reduced fuel revenues. Furthermore, the prominence of EVs is expected to exacerbate this problem. This thesis proposed a revision to the current user fee structure to address these impacts. This revision contains two major parts designed to address the system efficiency and equity in the near and long term. For the near term, this thesis recommended a variable tax scheme under which each vehicle class pays a different fuel tax rate. This ensures that both equity and system efficiency are improved during the transition to ECAV. In the long term, this thesis recommended supplementing the fuel tax with a distance based VMT tax, applicable to electric vehicles.<br></div>
290

Exploring the Relationship Among Transportation and Health Determinants in Diverse Geographic Settings

Lisa Lorena Losada Rojas (11481838) 20 April 2022 (has links)
<p>  </p> <p>Transportation and health are undeniably related. Transportation and its relationship with health are widely recognized as facing unique challenges in different geographic settings. However, research to date has mainly focused on understanding this relationship in urban areas. Remarkably, the importance of promoting physical activity through active travel (i.e., walking, biking, transit) is understudied in places other than urban areas. Increasing awareness regarding the ability of one's surroundings to encourage or inhibit active travel is critical to preparing us for the transformation of transportation habits. This issue takes on added significance considering telecommuting and the advent of autonomous vehicles.</p> <p>The overall goal of this dissertation is to examine the complex relationship between transportation and transport-related health determinants in diverse geographical settings (i.e., urban core, suburban, large rural towns, and rural areas) from an active travel perspective. To that end, four interdependent studies were conducted to address the following research questions: (i) Do the relationships among built environment, access to infrastructure, and physical activity differ across diverse geographic settings? (ii) What is the relationship among car usage, self-perceived health, and physical activity in rural areas? (iii) Which are the most significant pathways in the association between transportation and health in rural areas? (iv) What are the potential public health implications of adopting Autonomous Vehicles (AVs) in urban areas?</p> <p>First, the differences between various geographic settings regarding the built environment, access to infrastructure, and physical activity levels were assessed using individual-level data in the contiguous U.S. This dissertation employed behavioral science techniques (Structural Equation Modeling – Multi-group Analysis) to estimate how statistical constructs varied across multiple geographic settings. This dissertation concluded that the possibility of being physically active through active transportation, facilitated by the built environment and access, does not decrease linearly with the level of rurality defined in this study. Isolated Rural areas’-built environments and access to infrastructure were usually negatively associated with physical activity levels. This conclusion called for a deep analysis of rural areas regarding their ability to promote active travel.</p> <p>This dissertation studied rural areas' physical activity and its connection with socioeconomic determinants, perceived health, and car usage. Given that this relationship is described as non-linear, using statistical techniques such as path analysis allowed quantifying the direct and indirect effects among variables. This study concluded that high car usage and poor self-perceived health are mediators of physical activity levels. Therefore, efforts from both the transportation and health domain need to promote active travel in rural areas.</p> <p>Informed by transportation and health literature review, a conceptual framework was created by considering socioeconomic, personal, and physical transport-related health determinants. Structural equation models helped elucidate the complex relationships among determinants. The model results confirmed significant pathways among the various transport-related health determinants; hence comprehensive solutions need to be contemplated in future interventions to promote active travel. Interventions such as town center revitalization, heavy transit investments, and better broadband access that facilitate technology-enabled mobility services could significantly impact health outcomes in rural areas. Completing this objective fulfilled a pronounced research gap that has only been addressed using qualitative research. </p> <p>Finally, this dissertation examines how access to technologies, such as AVs, could impact the urban settings’-built environment and its potential to promote or inhibit active travel. Two urban settings were used as a case study since urban areas might be the first to experience this technology's deployment. This dissertation used cluster analysis and ordered probit models to understand AV adopters' individual and location-based characteristics. Our results suggest that AV implementation based only on the propensity to adopt might have adverse health outcomes (i.e., obesity). This dissertation points out the need for place-based interventions to enhance active travel and decrease the "obesogenic" environment that could arise in the AV era. </p> <p>Overall, we conclude that transportation's impact on public health cannot be seen as a "one exposure- one outcome- one solution" approach, and all-inclusive planning is needed to generate changes and prepare for transportation innovations to come. This dissertation proposed the ABC PATH framework that offers guidance to improve the population's health from transport-related changes comprehensively. The results of this research can help different organizations, such as planning organizations and rural health associations, advance communities' health through transportation.</p>

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