ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
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- All Subjects: robotics
Description
I study the performance of hedge fund managers, using quarterly stock holdings from 1995 to 2010. I use the holdings-based measure built on Ferson and Mo (2012) to decompose a manager's overall performance into stock selection and three components of timing ability: market return, volatility, and liquidity. At the aggregate level, I find that hedge fund managers have stock picking skills but no timing skills, and overall I do not find strong evidence to support their superiority. I show that the lack of abilities is driven by the large fluctuations of timing performance with market conditions. I find that conditioning information, equity capital constraints, and priority in stocks to liquidate can partly explain the weak evidence. At the individual fund level, bootstrap analysis results suggest that even top managers' abilities cannot be separated from luck. Also, I find that hedge fund managers exhibit short-horizon persistence in selectivity skill.
ContributorsKang, MinJeong (Author) / Aragon, George O. (Thesis advisor) / Hertzel, Michael G (Committee member) / Boguth, Oliver (Committee member) / Arizona State University (Publisher)
Created2013
Description
One of the main challenges in planetary robotics is to traverse the shortest path through a set of waypoints. The shortest distance between any two waypoints is a direct linear traversal. Often times, there are physical restrictions that prevent a rover form traversing straight to a waypoint. Thus, knowledge of the terrain is needed prior to traversal. The Digital Terrain Model (DTM) provides information about the terrain along with waypoints for the rover to traverse. However, traversing a set of waypoints linearly is burdensome, as the rovers would constantly need to modify their orientation as they successively approach waypoints. Although there are various solutions to this problem, this research paper proposes the smooth traversability of the rover using splines as a quick and easy implementation to traverse a set of waypoints. In addition, a rover was used to compare the smoothness of the linear traversal along with the spline interpolations. The data collected illustrated that spline traversals had a less rate of change in the velocity over time, indicating that the rover performed smoother than with linear paths.
ContributorsKamasamudram, Anurag (Author) / Saripalli, Srikanth (Thesis advisor) / Fainekos, Georgios (Thesis advisor) / Turaga, Pavan (Committee member) / Arizona State University (Publisher)
Created2013
Description
As the complexity of robotic systems and applications grows rapidly, development of high-performance, easy to use, and fully integrated development environments for those systems is inevitable. Model-Based Design (MBD) of dynamic systems using engineering software such as Simulink® from MathWorks®, SciCos from Metalau team and SystemModeler® from Wolfram® is quite popular nowadays. They provide tools for modeling, simulation, verification and in some cases automatic code generation for desktop applications, embedded systems and robots. For real-world implementation of models on the actual hardware, those models should be converted into compilable machine code either manually or automatically. Due to the complexity of robotic systems, manual code translation from model to code is not a feasible optimal solution so we need to move towards automated code generation for such systems. MathWorks® offers code generation facilities called Coder® products for this purpose. However in order to fully exploit the power of model-based design and code generation tools for robotic applications, we need to enhance those software systems by adding and modifying toolboxes, files and other artifacts as well as developing guidelines and procedures. In this thesis, an effort has been made to propose a guideline as well as a Simulink® library, StateFlow® interface API and a C/C++ interface API to complete this toolchain for NAO humanoid robots. Thus the model of the hierarchical control architecture can be easily and properly converted to code and built for implementation.
ContributorsRaji Kermani, Ramtin (Author) / Fainekos, Georgios (Thesis advisor) / Lee, Yann-Hang (Committee member) / Sarjoughian, Hessam S. (Committee member) / Arizona State University (Publisher)
Created2013
Description
The development of advanced, anthropomorphic artificial hands aims to provide upper extremity amputees with improved functionality for activities of daily living. However, many state-of-the-art hands have a large number of degrees of freedom that can be challenging to control in an intuitive manner. Automated grip responses could be built into artificial hands in order to enhance grasp stability and reduce the cognitive burden on the user. To this end, three studies were conducted to understand how human hands respond, passively and actively, to unexpected perturbations of a grasped object along and about different axes relative to the hand. The first study investigated the effect of magnitude, direction, and axis of rotation on precision grip responses to unexpected rotational perturbations of a grasped object. A robust "catch-up response" (a rapid, pulse-like increase in grip force rate previously reported only for translational perturbations) was observed whose strength scaled with the axis of rotation. Using two haptic robots, we then investigated the effects of grip surface friction, axis, and direction of perturbation on precision grip responses for unexpected translational and rotational perturbations for three different hand-centric axes. A robust catch-up response was observed for all axes and directions for both translational and rotational perturbations. Grip surface friction had no effect on the stereotypical catch-up response. Finally, we characterized the passive properties of the precision grip-object system via robot-imposed impulse perturbations. The hand-centric axis associated with the greatest translational stiffness was different than that for rotational stiffness. This work expands our understanding of the passive and active features of precision grip, a hallmark of human dexterous manipulation. Biological insights such as these could be used to enhance the functionality of artificial hands and the quality of life for upper extremity amputees.
ContributorsDe Gregorio, Michael (Author) / Santos, Veronica J. (Thesis advisor) / Artemiadis, Panagiotis K. (Committee member) / Santello, Marco (Committee member) / Sugar, Thomas (Committee member) / Helms Tillery, Stephen I. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Human fingertips contain thousands of specialized mechanoreceptors that enable effortless physical interactions with the environment. Haptic perception capabilities enable grasp and manipulation in the absence of visual feedback, as when reaching into one's pocket or wrapping a belt around oneself. Unfortunately, state-of-the-art artificial tactile sensors and processing algorithms are no match for their biological counterparts. Tactile sensors must not only meet stringent practical specifications for everyday use, but their signals must be processed and interpreted within hundreds of milliseconds. Control of artificial manipulators, ranging from prosthetic hands to bomb defusal robots, requires a constant reliance on visual feedback that is not entirely practical. To address this, we conducted three studies aimed at advancing artificial haptic intelligence. First, we developed a novel, robust, microfluidic tactile sensor skin capable of measuring normal forces on flat or curved surfaces, such as a fingertip. The sensor consists of microchannels in an elastomer filled with a liquid metal alloy. The fluid serves as both electrical interconnects and tunable capacitive sensing units, and enables functionality despite substantial deformation. The second study investigated the use of a commercially-available, multimodal tactile sensor (BioTac sensor, SynTouch) to characterize edge orientation with respect to a body fixed reference frame, such as a fingertip. Trained on data from a robot testbed, a support vector regression model was developed to relate haptic exploration actions to perception of edge orientation. The model performed comparably to humans for estimating edge orientation. Finally, the robot testbed was used to perceive small, finger-sized geometric features. The efficiency and accuracy of different haptic exploratory procedures and supervised learning models were assessed for estimating feature properties such as type (bump, pit), order of curvature (flat, conical, spherical), and size. This study highlights the importance of tactile sensing in situations where other modalities fail, such as when the finger itself blocks line of sight. Insights from this work could be used to advance tactile sensor technology and haptic intelligence for artificial manipulators that improve quality of life, such as prosthetic hands and wheelchair-mounted robotic hands.
ContributorsPonce Wong, Ruben Dario (Author) / Santos, Veronica J (Thesis advisor) / Artemiadis, Panagiotis K (Committee member) / Helms Tillery, Stephen I (Committee member) / Posner, Jonathan D (Committee member) / Runger, George C. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Electromyogram (EMG)-based control interfaces are increasingly used in robot teleoperation, prosthetic devices control and also in controlling robotic exoskeletons. Over the last two decades researchers have come up with a plethora of decoding functions to map myoelectric signals to robot motions. However, this requires a lot of training and validation data sets, while the parameters of the decoding function are specific for each subject. In this thesis we propose a new methodology that doesn't require training and is not user-specific. The main idea is to supplement the decoding functional error with the human ability to learn inverse model of an arbitrary mapping function. We have shown that the subjects gradually learned the control strategy and their learning rates improved. We also worked on identifying an optimized control scheme that would be even more effective and easy to learn for the subjects. Optimization was done by taking into account that muscles act in synergies while performing a motion task. The low-dimensional representation of the neural activity was used to control a two-dimensional task. Results showed that in the case of reduced dimensionality mapping, the subjects were able to learn to control the device in a slower pace, however they were able to reach and retain the same level of controllability. To summarize, we were able to build an EMG-based controller for robot devices that would work for any subject, without any training or decoding function, suggesting human-embedded controllers for robotic devices.
ContributorsAntuvan, Chris Wilson (Author) / Artemiadis, Panagiotis (Thesis advisor) / Muthuswamy, Jitendran (Committee member) / Santos, Veronica J (Committee member) / Arizona State University (Publisher)
Created2013
Description
Linear Temporal Logic is gaining increasing popularity as a high level specification language for robot motion planning due to its expressive power and scalability of LTL control synthesis algorithms. This formalism, however, requires expert knowledge and makes it inaccessible to non-expert users. This thesis introduces a graphical specification environment to create high level motion plans to control robots in the field by converting a visual representation of the motion/task plan into a Linear Temporal Logic (LTL) specification. The visual interface is built on the Android tablet platform and provides functionality to create task plans through a set of well defined gestures and on screen controls. It uses the notion of waypoints to quickly and efficiently describe the motion plan and enables a variety of complex Linear Temporal Logic specifications to be described succinctly and intuitively by the user without the need for the knowledge and understanding of LTL specification. Thus, it opens avenues for its use by personnel in military, warehouse management, and search and rescue missions. This thesis describes the construction of LTL for various scenarios used for robot navigation using the visual interface developed and leverages the use of existing LTL based motion planners to carry out the task plan by a robot.
ContributorsSrinivas, Shashank (Author) / Fainekos, Georgios (Thesis advisor) / Baral, Chitta (Committee member) / Burleson, Winslow (Committee member) / Arizona State University (Publisher)
Created2013
Description
"YouTube Shakespeares" is a study of Shakespeare online videos and the people who create, upload, and view them on YouTube. Employing an interdisciplinary approach, this work is a remix of theories and methodologies from literary, performance, (social) media, fan, and Internet studies that expands the field of Shakespeare studies. This dissertation explores the role of YouTube users and their activities, the expansion of literary research methods onto digital media venues, YouTube as site of Shakespeare performance, and YouTube Shakespeares' fan communities. It analyzes a broad array of Shakespeare visual performances including professional and user-generated mashups, remixes, film clips, auditions, and high school performances. A rich avenue for the study of people's viewing and reception of Shakespeare, YouTube tests the (un)limitations of Shakespeare adaptation. This work explores the ethical implications of researching performances that include human subjects, arguing that their presence frequently complicates common concepts of public and private identities. Although YouTube is a "published" forum for social interactivity and video repository, this work urges digital humanities scholars to recognize and honor the human users entailed in the videos not as text, but as human subjects. Shifting the study focus to human subjects demands a revision of research methods and publications protocols as the researcher repositions herself into the role of virtual ethnographer. "YouTube Shakespeares" develops its own ethics-based, online research method, which includes seeking Institutional Board Review approval and online interviews. The second half of the dissertation shifts from methodology to theorizing YouTube Shakespeares' performance spaces as analogs to the interactive and imaginary areas of Shakespeare's early modern theatre. Additionally, this work argues that YouTube Shakespeares' creators and commentators are fans. "YouTube Shakespeares" is one of the first Shakespeare-centric studies to employ fan studies as a critical lens to explore the cultural significance and etiquette of people's online Shakespeare performance activities. The work ends with a conversation about the issues of ephemerality, obsolescence, and concerns about the instability of digital and online materials, noting the risk of evidentiary loss of research materials is far outweighed by a scholarly critical registration of YouTube in the genealogy of Shakespeare performance.
ContributorsFazel, Valerie Margaret (Author) / Thompson, Ayanna (Thesis advisor) / Ryner, Bradley (Committee member) / Fox, Cora (Committee member) / Arizona State University (Publisher)
Created2013
Description
The integration of yoga into the music curriculum has the potential of offering many immediate and life-long benefits to musicians. Yoga can help address issues such as performance anxiety and musculoskeletal problems, and enhance focus and awareness during musical practice and performance. Although the philosophy of yoga has many similarities to the process of learning a musical instrument, the benefits of yoga for musicians is a topic that has gained attention only recently. This document explores several ways in which the practice and philosophy of yoga can be fused with saxophone pedagogy as one way to prepare students for a healthy and successful musical career. A six-week study at Arizona State University was conducted to observe the effects of regular yoga practice on collegiate saxophone students. Nine participants attended a sixty-minute "yoga for musicians" class twice a week. Measures included pre- and post- study questionnaires as well as personal journals kept throughout the duration of the study. These self-reported results showed that yoga had positive effects on saxophone playing. It significantly increased physical comfort and positive thinking, and improved awareness of habitual patterns and breath control. Student participants responded positively to the idea of integrating such a course into the music curriculum. The integration of yoga and saxophone by qualified professionals could also be a natural part of studio class and individual instruction. Carrie Koffman, professor of saxophone at The Hartt School, University of Hartford, has established one strong model for the combination of these disciplines. Her methods and philosophy, together with the basics of Western-style hatha yoga, clinical reports on performance injuries, and qualitative data from the ASU study are explored. These inquiries form the foundation of a new model for integrating yoga practice regularly into the saxophone studio.
ContributorsAdams, Allison Dromgold (Author) / Norton, Kay (Thesis advisor) / Hill, Gary (Committee member) / McAllister, Timothy (Committee member) / Micklich, Albie (Committee member) / Standley, Eileen (Committee member) / Arizona State University (Publisher)
Created2012
Description
The Holocaust and the effects it has had upon witnesses has been a topic of study for nearly six decades; however, few angles of research have been conducted relating to the long-term effects of the Holocaust upon the children and grandchildren of Holocaust survivors--the After Generations. The After Generations are considered the proof--the living legacies--that their parents and grandparents survived. Growing up with intimate knowledge of the atrocities that occurred during the Holocaust, members of the After Generations not only carry with them their family's story, but also their own vicarious experience(s) of trauma. From this legacy comes a burden of responsibility to those who perished, their survivor parents/grandparents, the stories that were shared, as well as to future generations. Using grounded theory method, this study not only explores the long-term effects of the Holocaust upon members of the After Generations, but what it means to responsibly remember the stories from the Holocaust, as well as how individuals might ethically represent such stories/memories. Findings that developed out of an axial analysis of interview transcripts and journal writing, as well as the later development of a performance script, are embodied in a manner that allows the actual language and experiences of the participants to be collectively witnessed both symbolically and visually. Through their desire to remember, members of the After Generations demonstrate how they plan to carry on traditions, live lives that honor those that came before them, and maintain hope for the future. In so doing, the stories shared reveal the centrality of the Holocaust in the lives of members of the After Generations through their everyday choices to responsibly and actively remember through their art, writings, life-work, as well as from within their work in their local communities. Such acts of remembrance are important to the education of others as well as to the construction and maintenance of the After Generations' identities. The representation of these voices acts as a reminder of how hatred and its all-consuming characteristics can affect not only the person targeted, but multiple generations, as well.
ContributorsRath, Sandra (Author) / de la Garza, Sarah Amira (Thesis advisor) / Underiner, Tamara (Committee member) / Corey, Frederick C. (Committee member) / Eisenberg, Judith (Committee member) / Arizona State University (Publisher)
Created2012