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Description
Robert (Bob) Barnhill came to ASU in 1986 as Chair of the Computer Science Department and left in 1997 as the Vice President for Research. The interview addresses a number of topics including the beginnings of Computer Graphics, moving the Computer Science Department to a more research-oriented effort, achieving Research 1 status, working with the University of Arizona to develop a new statewide Intellectual Property template, dodging the Unabomber and playing soccer. Common themes throughout the interview include Bob’s success at getting groups of people to actually do something other than just meet and the importance of a strategic plan.
ContributorsScheatzle, Dave (Interviewer) / Storad, Conrad (Producer)
Created2011-04-11
Description
The purpose of this project was to develop a system capable of launching projectiles at a curved trajectory. This system effectively imparts spin on projectiles, enabling controlled indirect fire for the intended use of military operations. Through this proof of concept, it was determined whether a scaled system would be a viable solution to the issue of controlled indirect fire in dense urban areas. Using a series of coaxial motors with independently controlled speeds, it was possible to alter the horizontal and vertical displacement of objects in flight.
ContributorsShores, Jamie (Author) / Grewal, Anoop (Thesis director) / Latino, Steven (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Energy performance and efficiency plays of major role in the operations of K-12 schools, as it is a significant expense and a source of budgetary pressure upon schools. Energy performance is tied to the physical infrastructure of schools, as well as the operational and behavioral patterns they accommodate. Little documentation exists within the existing literature on the measured post-occupancy performance of schools once they have begun measuring and tracking their energy performance. Further, little is known about the patterns of change over time in regard to energy performance and whether there is differentiation in these patterns between school districts.
This paper examines the annual Energy Use Intensity (EUI) of 28 different K-12 schools within the Phoenix Metropolitan Region of Arizona over the span of five years and presents an analysis of changes in energy performance resulting from the measurement of energy use in K-12 schools. This paper also analyzes the patterns of change in energy use over time and provides a comparison of these patterns by school district.
An analysis of the energy performance data for the selected schools revealed a significant positive impact on the ability for schools to improve their energy performance through ongoing performance measurement. However, while schools tend to be able to make energy improvements through the implementation of energy measurement and performance tracking, deviation may exist in their ability to maintain ongoing energy performance over time. The results suggest that implementation of ongoing measurement is likely to produce positive impacts on the energy performance of schools, however further research is recommended to enhance and refine these results.
This paper examines the annual Energy Use Intensity (EUI) of 28 different K-12 schools within the Phoenix Metropolitan Region of Arizona over the span of five years and presents an analysis of changes in energy performance resulting from the measurement of energy use in K-12 schools. This paper also analyzes the patterns of change in energy use over time and provides a comparison of these patterns by school district.
An analysis of the energy performance data for the selected schools revealed a significant positive impact on the ability for schools to improve their energy performance through ongoing performance measurement. However, while schools tend to be able to make energy improvements through the implementation of energy measurement and performance tracking, deviation may exist in their ability to maintain ongoing energy performance over time. The results suggest that implementation of ongoing measurement is likely to produce positive impacts on the energy performance of schools, however further research is recommended to enhance and refine these results.
ContributorsThurston, Anna (Author) / Sullivan, Kenneth (Thesis advisor) / Okamura, Patrick (Committee member) / Slife, Curtis (Committee member) / Arizona State University (Publisher)
Created2015
Description
Distributed wireless sensor networks (WSNs) have attracted researchers recently due to their advantages such as low power consumption, scalability and robustness to link failures. In sensor networks with no fusion center, consensus is a process where
all the sensors in the network achieve global agreement using only local transmissions. In this dissertation, several consensus and consensus-based algorithms in WSNs are studied.
Firstly, a distributed consensus algorithm for estimating the maximum and minimum value of the initial measurements in a sensor network in the presence of communication noise is proposed. In the proposed algorithm, a soft-max approximation together with a non-linear average consensus algorithm is used. A design parameter controls the trade-off between the soft-max error and convergence speed. An analysis of this trade-off gives guidelines towards how to choose the design parameter for the max estimate. It is also shown that if some prior knowledge of the initial measurements is available, the consensus process can be accelerated.
Secondly, a distributed system size estimation algorithm is proposed. The proposed algorithm is based on distributed average consensus and L2 norm estimation. Different sources of error are explicitly discussed, and the distribution of the final estimate is derived. The CRBs for system size estimator with average and max consensus strategies are also considered, and different consensus based system size estimation approaches are compared.
Then, a consensus-based network center and radius estimation algorithm is described. The center localization problem is formulated as a convex optimization problem with a summation form by using soft-max approximation with exponential functions. Distributed optimization methods such as stochastic gradient descent and diffusion adaptation are used to estimate the center. Then, max consensus is used to compute the radius of the network area.
Finally, two average consensus based distributed estimation algorithms are introduced: distributed degree distribution estimation algorithm and algorithm for tracking the dynamics of the desired parameter. Simulation results for all proposed algorithms are provided.
all the sensors in the network achieve global agreement using only local transmissions. In this dissertation, several consensus and consensus-based algorithms in WSNs are studied.
Firstly, a distributed consensus algorithm for estimating the maximum and minimum value of the initial measurements in a sensor network in the presence of communication noise is proposed. In the proposed algorithm, a soft-max approximation together with a non-linear average consensus algorithm is used. A design parameter controls the trade-off between the soft-max error and convergence speed. An analysis of this trade-off gives guidelines towards how to choose the design parameter for the max estimate. It is also shown that if some prior knowledge of the initial measurements is available, the consensus process can be accelerated.
Secondly, a distributed system size estimation algorithm is proposed. The proposed algorithm is based on distributed average consensus and L2 norm estimation. Different sources of error are explicitly discussed, and the distribution of the final estimate is derived. The CRBs for system size estimator with average and max consensus strategies are also considered, and different consensus based system size estimation approaches are compared.
Then, a consensus-based network center and radius estimation algorithm is described. The center localization problem is formulated as a convex optimization problem with a summation form by using soft-max approximation with exponential functions. Distributed optimization methods such as stochastic gradient descent and diffusion adaptation are used to estimate the center. Then, max consensus is used to compute the radius of the network area.
Finally, two average consensus based distributed estimation algorithms are introduced: distributed degree distribution estimation algorithm and algorithm for tracking the dynamics of the desired parameter. Simulation results for all proposed algorithms are provided.
ContributorsZhang, Sai (Electrical engineer) (Author) / Tepedelenlioğlu, Cihan (Thesis advisor) / Spanias, Andreas (Thesis advisor) / Tsakalis, Kostas (Committee member) / Bliss, Daniel (Committee member) / Arizona State University (Publisher)
Created2017
Description
NIPAAm co-DEAEMA hydrogels are a potential solution for sustained, local delivery of ketorolac tromethamine. Current methods of postoperative pain management, such as local anesthetics, NSAIDs, and opioids, can be improved by minimizing side effects while still effectively treating severe and extreme pain. Though high doses of ketorolac can be toxic, sustained, local delivery via hydrogels offers a promising solution. Four ketorolac release studies were conducted using PNDJ hydrogels formulated by Sonoran Biosciences. The first two studies tested a range of JAAm concentration between 1.4 and 2.2 mole percent. Both had high initial release rates lasting less than 7 days and appeared to be unaffected by JAAm content. Tobramycin slowed down the release of ketorolac but was unable to sustain release for more than 6 days. Incorporating DEAEMA prolonged the release of ketorolac for up to 14 days with significant reductions in initial burst release rate. Low LCST of NIPAAM co-DEAEMA polymer is problematic for even drug distribution and future in vivo applications.
ContributorsHui, Nathan (Author) / Vernon, Brent (Thesis director) / Heffernan, John (Committee member) / School of International Letters and Cultures (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The goal of this thesis project was to build an understanding of supersonic projectile dynamics through the creation of a trajectory model that incorporates several different aerodynamic concepts and builds a criteria for the stability of a projectile. This was done iteratively where the model was built from a foundation of kinematics with various aerodynamic principles being added incrementally. The primary aerodynamic principle that influenced the trajectory of the projectile was in the coefficient of drag. The drag coefficient was split into three primary components: the form drag, skin friction drag, and base pressure drag. These together made up the core of the model, additional complexity served to increase the accuracy of the model and generalize to different projectile profiles.
ContributorsBlair, Martin (Co-author) / Armenta, Francisco (Co-author) / Takahashi, Timothy (Thesis director) / Herrmann, Marcus (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Effective communication and engineering are not a natural pairing. The incongruence is because engineering students are focused on making, designing and analyzing. Since these are the core functions of the field there is not a direct focus on developing communication skills. This honors thesis explores the role and expectations for student engineers within the undergraduate engineering education experience to present and communicate ideas. The researchers interviewed faculty about their perspective on students' abilities with respect to their presentation skills to inform the design of a workshop series of interventions intended to make engineering students better communicators.
ContributorsAlbin, Joshua Alexander (Co-author) / Brancati, Sara (Co-author) / Lande, Micah (Thesis director) / Martin, Thomas (Committee member) / Industrial, Systems and Operations Engineering Program (Contributor) / Software Engineering (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Solar panels need to be both cost effective and environmentally friendly to compete with traditional energy forms. Photovoltaic recycling has the potential to mitigate the harm of waste, which is often landfilled, while putting material back into the manufacturing process. Out of many, three methods show much promise: Full Recovery End-of-Life Photovoltaic (FRELP), mechanical, and sintering-based recycling. FRELP recycling has quickly gained prominence in Europe and promises to fully recover the components in a solar cell. The mechanical method has produced high yields of valuable materials using basic and inexpensive processes. The sintering method has the potential to tap into a large market for feldspar. Using a levelized cost of electricity (LCOE) analysis, the three methods could be compared on an economic basis. This showed that the mechanical method is least expensive, and the sintering method is the most expensive. Using this model, all recycling methods are less cost effective than the control analysis without recycling. Sensitivity analyses were then done on the effect of the discount rate, capacity factor, and lifespan on the LCOE. These results showed that the change in capacity factor had the most significant effect on the levelized cost of electricity. A final sensitivity analysis was done based on the decreased installation and balance of systems costs in 2025. With a 55% decrease in these costs, the LCOE decreased by close to $0.03/kWh for each method. Based on these results, the cost of each recycling method would be a more considerable proportion of the overall LCOE of the solar farm.
ContributorsMeister, William Frederick (Author) / Goodnick, Stephen (Thesis director) / Phelan, Patrick (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05