This collection includes both ASU Theses and Dissertations, submitted by graduate students, and the Barrett, Honors College theses submitted by undergraduate students. 

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Concrete columns constitute the fundamental supports of buildings, bridges, and various other infrastructures, and their failure could lead to the collapse of the entire structure. As such, great effort goes into improving the fire resistance of such columns. In a time sensitive fire situation, a delay in the failure of

Concrete columns constitute the fundamental supports of buildings, bridges, and various other infrastructures, and their failure could lead to the collapse of the entire structure. As such, great effort goes into improving the fire resistance of such columns. In a time sensitive fire situation, a delay in the failure of critical load bearing structures can lead to an increase in time allowed for the evacuation of occupants, recovery of property, and access to the fire. Much work has been done in improving the structural performance of concrete including reducing column sizes and providing a safer structure. As a result, high-strength (HS) concrete has been developed to fulfill the needs of such improvements. HS concrete varies from normal-strength (NS) concrete in that it has a higher stiffness, lower permeability and larger durability. This, unfortunately, has resulted in poor performance under fire. The lower permeability allows for water vapor to build up causing HS concrete to suffer from explosive spalling under rapid heating. In addition, the coefficient of thermal expansion (CTE) of HS concrete is lower than that of NS concrete. In this study, the effects of introducing a region of crumb rubber concrete into a steel-reinforced concrete column were analyzed. The inclusion of crumb rubber concrete into a column will greatly increase the thermal resistivity of the overall column, leading to a reduction in core temperature as well as the rate at which the column is heated. Different cases were analyzed while varying the positioning of the crumb-rubber region to characterize the effect of position on the improvement of fire resistance. Computer simulated finite element analysis was used to calculate the temperature and strain distribution with time across the column's cross-sectional area with specific interest in the steel - concrete region. Of the several cases which were investigated, it was found that the improvement of time before failure ranged between 32 to 45 minutes.
ContributorsZiadeh, Bassam Mohammed (Author) / Phelan, Patrick (Thesis advisor) / Kaloush, Kamil (Thesis advisor) / Jiang, Hanqing (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Locomotion of microorganisms is commonly observed in nature. Although microorganism locomotion is commonly attributed to mechanical deformation of solid appendages, in 1956 Nobel Laureate Peter Mitchell proposed that an asymmetric ion flux on a bacterium's surface could generate electric fields that drive locomotion via self-electrophoresis. Recent advances in nanofabrication have

Locomotion of microorganisms is commonly observed in nature. Although microorganism locomotion is commonly attributed to mechanical deformation of solid appendages, in 1956 Nobel Laureate Peter Mitchell proposed that an asymmetric ion flux on a bacterium's surface could generate electric fields that drive locomotion via self-electrophoresis. Recent advances in nanofabrication have enabled the engineering of synthetic analogues, bimetallic colloidal particles, that swim due to asymmetric ion flux originally proposed by Mitchell. Bimetallic colloidal particles swim through aqueous solutions by converting chemical fuel to fluid motion through asymmetric electrochemical reactions. This dissertation presents novel bimetallic motor fabrication strategies, motor functionality, and a study of the motor collective behavior in chemical concentration gradients. Brownian dynamics simulations and experiments show that the motors exhibit chemokinesis, a motile response to chemical gradients that results in net migration and concentration of particles. Chemokinesis is typically observed in living organisms and distinct from chemotaxis in that there is no particle directional sensing. The synthetic motor chemokinesis observed in this work is due to variation in the motor's velocity and effective diffusivity as a function of the fuel and salt concentration. Static concentration fields are generated in microfluidic devices fabricated with porous walls. The development of nanoscale particles that swim autonomously and collectively in chemical concentration gradients can be leveraged for a wide range of applications such as directed drug delivery, self-healing materials, and environmental remediation.
ContributorsWheat, Philip Matthew (Author) / Posner, Jonathan D (Thesis advisor) / Phelan, Patrick (Committee member) / Chen, Kangping (Committee member) / Buttry, Daniel (Committee member) / Calhoun, Ronald (Committee member) / Arizona State University (Publisher)
Created2011
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Description
In this thesis the performance of a Hybrid AC System (HACS) is modeled and optimized. The HACS utilizes solar photovoltaic (PV) panels to help reduce the demand from the utility during peak hours. The system also includes an ice Thermal Energy Storage (TES) tank to accumulate cooling energy during off-peak

In this thesis the performance of a Hybrid AC System (HACS) is modeled and optimized. The HACS utilizes solar photovoltaic (PV) panels to help reduce the demand from the utility during peak hours. The system also includes an ice Thermal Energy Storage (TES) tank to accumulate cooling energy during off-peak hours. The AC runs continuously on grid power during off-peak hours to generate cooling for the house and to store thermal energy in the TES. During peak hours, the AC runs on the power supplied from the PV, and cools the house along with the energy stored in the TES. A higher initial cost is expected due to the additional components of the HACS (PV and TES), but a lower operational cost due to higher energy efficiency, energy storage and renewable energy utilization. A house cooled by the HACS will require a smaller size AC unit (about 48% less in the rated capacity), compared to a conventional AC system. To compare the cost effectiveness of the HACS with a regular AC system, time-of-use (TOU) utility rates are considered, as well as the cost of the system components and the annual maintenance. The model shows that the HACS pays back its initial cost of $28k in about 6 years with an 8% APR, and saves about $45k in total cost when compared to a regular AC system that cools the same house for the same period of 6 years.
ContributorsJubran, Sadiq (Author) / Phelan, Patrick (Thesis advisor) / Calhoun, Ronald (Committee member) / Trimble, Steve (Committee member) / Arizona State University (Publisher)
Created2011
Description
As the demand for power increases in populated areas, so will the demand for water. Current power plant technology relies heavily on the Rankine cycle in coal, nuclear and solar thermal power systems which ultimately use condensers to cool the steam in the system. In dry climates, the amount of

As the demand for power increases in populated areas, so will the demand for water. Current power plant technology relies heavily on the Rankine cycle in coal, nuclear and solar thermal power systems which ultimately use condensers to cool the steam in the system. In dry climates, the amount of water to cool off the condenser can be extremely large. Current wet cooling technologies such as cooling towers lose water from evaporation. One alternative to prevent this would be to implement a radiative cooling system. More specifically, a system that utilizes the volumetric radiation emission from water to the night sky could be implemented. This thesis analyzes the validity of a radiative cooling system that uses direct radiant emission to cool water. A brief study on potential infrared transparent cover materials such as polyethylene (PE) and polyvinyl carbonate (PVC) was performed. Also, two different experiments to determine the cooling power from radiation were developed and run. The results showed a minimum cooling power of 33.7 W/m2 for a vacuum insulated glass system and 37.57 W/m2 for a tray system with a maximum of 98.61 Wm-2 at a point when conduction and convection heat fluxes were considered to be zero. The results also showed that PE proved to be the best cover material. The minimum numerical results compared well with other studies performed in the field using similar techniques and materials. The results show that a radiative cooling system for a power plant could be feasible given that the cover material selection is narrowed down, an ample amount of land is available and an economic analysis is performed proving it to be cost competitive with conventional systems.
ContributorsOvermann, William (Author) / Phelan, Patrick (Thesis advisor) / Trimble, Steve (Committee member) / Taylor, Robert (Committee member) / Arizona State University (Publisher)
Created2011
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Description
A low cost expander, combustor device that takes compressed air, adds thermal energy and then expands the gas to drive an electrical generator is to be designed by modifying an existing reciprocating spark ignition engine. The engine used is the 6.5 hp Briggs and Stratton series 122600 engine. Compressed air

A low cost expander, combustor device that takes compressed air, adds thermal energy and then expands the gas to drive an electrical generator is to be designed by modifying an existing reciprocating spark ignition engine. The engine used is the 6.5 hp Briggs and Stratton series 122600 engine. Compressed air that is stored in a tank at a particular pressure will be introduced during the compression stage of the engine cycle to reduce pump work. In the modified design the intake and exhaust valve timings are modified to achieve this process. The time required to fill the combustion chamber with compressed air to the storage pressure immediately before spark and the state of the air with respect to crank angle is modeled numerically using a crank step energy and mass balance model. The results are used to complete the engine cycle analysis based on air standard assumptions and air to fuel ratio of 15 for gasoline. It is found that at the baseline storage conditions (280 psi, 70OF) the modified engine does not meet the imposed constraints of staying below the maximum pressure of the unmodified engine. A new storage pressure of 235 psi is recommended. This only provides a 7.7% increase in thermal efficiency for the same work output. The modification of this engine for this low efficiency gain is not recommended.
ContributorsJoy, Lijin (Author) / Trimble, Steve (Thesis advisor) / Davidson, Joseph (Committee member) / Phelan, Patrick (Committee member) / Arizona State University (Publisher)
Created2011
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Description

Within the last decade, it has become increasingly apparent that the effects of climate change are getting harder and harder to ignore. This fact has led to increased interest in sustainability and an increased pressure from consumers to have these ideals implemented into a variety of global industries. The fashion

Within the last decade, it has become increasingly apparent that the effects of climate change are getting harder and harder to ignore. This fact has led to increased interest in sustainability and an increased pressure from consumers to have these ideals implemented into a variety of global industries. The fashion industry, in particular, has been facing this pressure toward the desire for sustainable products is the fashion industry. Over the last five years, sustainability has become a main focus within the fashion industry. Countless brands now include sustainability within their marketing tactics and a variety of fashion organizations release reports on the unsustainable practices that currently dominate fashion production. These misleading marketing tactics and enigmatic intensive reports lead to confusion on what sustainable fashion actually looks like for both consumers and suppliers alike.<br/> This report attempts to help tackle this problem by using sustainable fashion certifications as a tactic to prove sustainability within business procedures. To compare eight of the most common fashion certifications, this paper assumes a systems thinking approach to creating an assessment framework, which is then applied to said certifications. To back up the importance of the topic, this paper presents key points of the current issues related to this case, which then contribute to the integration of basic sustainability assessment criteria and case-specific factors into overarching core criteria. The application of this framework is utilized to determine which certifications cover certain aspects of the curated core criteria. This is then used to present consumers and manufacturers with a more accurate understanding of each of these certifications. This information is then followed up with a recommendation of certifications that align most within researched-based consumer and supplier desires.

ContributorsReid, Christopher Patrick (Author) / Sewell, Dennita (Thesis director) / Kosak, Jessica (Committee member) / Department of Management and Entrepreneurship (Contributor, Contributor) / School of Art (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

When examining the average college campus, it becomes obvious that students feel rushed from one place to another as they try to participate in class, clubs, and extracurricular activities. One way that students can feel more comfortable and relaxed around campus is to introduce the aspect of gaming. Studies show

When examining the average college campus, it becomes obvious that students feel rushed from one place to another as they try to participate in class, clubs, and extracurricular activities. One way that students can feel more comfortable and relaxed around campus is to introduce the aspect of gaming. Studies show that “Moderate videogame play has been found to contribute to emotional stability” (Jones, 2014). This demonstrates that the stress of college can be mitigated by introducing the ability to interact with video games. This same concept has been applied in the workplace, where studies have shown that “Gaming principles such as challenges, competition, rewards and personalization keep employees engaged and learning” (Clark, 2020). This means that if we manage to gamify the college experience, students will be more engaged which will increase and stabilize the retention rate of colleges which utilize this type of experience. Gaming allows students to connect with their peers in a casual environment while also allowing them to find resources around campus and find new places to eat and relax. We plan to gamify the college experience by introducing augmented reality in the form of an app. Augmented reality is “. . . a technology that combines virtual information with the real world” (Chen, 2019). College students will be able to utilize the resources and amenities available to them on campus while completing quests that help them within the application. This demonstrates the ability for video games to engage students using artificial tasks but real actions and experiences which help them feel more connected to campus. Our Founders Lab team has developed and tested an AR application that can be used to connect students with their campus and the resources available to them.

ContributorsKlein, Jonathan (Co-author) / Rangarajan, Padmapriya (Co-author) / Li, Shimei (Co-author) / Byrne, Jared (Thesis director) / Pierce, John (Committee member) / School of International Letters and Cultures (Contributor) / Department of Management and Entrepreneurship (Contributor) / Sandra Day O'Connor College of Law (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

The digital education market has been expanding rapidly during the last few years, providing ample opportunity in the future. There are many technologies involved in this market, with the most significant being cloud client services, edge computing, and interactive flat panel displays (IFPDs). Combined, these technologies represent ninety-two percent of

The digital education market has been expanding rapidly during the last few years, providing ample opportunity in the future. There are many technologies involved in this market, with the most significant being cloud client services, edge computing, and interactive flat panel displays (IFPDs). Combined, these technologies represent ninety-two percent of the Serviceable Available Market with IFPDs as the largest opportunity with sixty-nine percent (Company X Data). Cloud computing provides anytime/anywhere services that can be accessed from any device: e-portfolios, content access, and creation. Edge computing processes data closer to its source and the point of service delivery, providing ultra-low latency to help boost efficiency, mainly used for data processing. Lastly, IFPDs are touchscreen display devices ideal for collaborative spaces and meeting rooms. They are a substitute for outdated projector technology and provide better connectivity and built-in software solutions. <br/>We decided to develop a strategy to expand the market share in the IFPD market because it is the largest, and we consider Company X has a significant advantage in this sector. Company X manufactures the processors used in IFPDs and has established good relationships with manufacturers of these devices.

ContributorsPhillips, Maya (Co-author) / Hauck, Tanner (Co-author) / Morales Rincon, Herwin (Thesis director) / Koroli, Eri (Thesis director) / Simonson, Mark (Committee member) / Department of Finance (Contributor) / Department of Management and Entrepreneurship (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

Waste pickers are the victims of harsh economic and social factors that have hurt many<br/>developing countries and billions of people around the world. Due to the rise of industrialization<br/>since the 19th century, waste and disposable resources have been discarded around the world to<br/>provide more resources, products, and services to wealthy

Waste pickers are the victims of harsh economic and social factors that have hurt many<br/>developing countries and billions of people around the world. Due to the rise of industrialization<br/>since the 19th century, waste and disposable resources have been discarded around the world to<br/>provide more resources, products, and services to wealthy countries. This has put developing<br/>countries in a precarious position where people have had very few economic opportunities<br/>besides taking on the role of waste pickers, who not only face physical health consequences due<br/>to the work they do but also face exclusion from society due to the negative views of waste<br/>pickers. Many people view waste pickers as scavengers and people who survive off of doing<br/>dirty work, which creates tensions between waste pickers and others in society. This even leads<br/>to many countries outlawing waste picking and has led to the brutal treatment of waste pickers<br/>throughout the world and has even led to thousands of waste pickers being killed by anti-waste<br/>picker groups and law enforcement organizations in many countries.<br/>Waste pickers are often at the bottom of supply chains as they take resources that have<br/>been used and discarded, and provide them to recyclers, waste management organizations, and<br/>others who are able to turn these resources into usable materials again. Waste pickers do not have<br/>many opportunities to rise above the situation they are in as waste picking has become the only<br/>option for many people who need to provide for themselves and their families. They are not<br/>compensated very well for the work they do, which also contributes to the situation where waste<br/>pickers are forced into a position of severe health risks, backlash from society and governments,<br/>not being able to seek better opportunities due to a lack of earning potential, and not being<br/>connected with end-users. Now is the time to create new business models that solve these large<br/>problems in our global society and create a sustainable way to ensure that waste pickers are<br/>treated properly around the world.

ContributorsKapps, Jack Michael (Co-author) / Kidd, Isabella (Co-author) / Urbina-Bernal, Alejandro (Co-author) / Bryne, Jared (Thesis director) / Marseille, Alicia (Committee member) / Jordan, Amanda (Committee member) / Department of Management and Entrepreneurship (Contributor) / Department of Marketing (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

From exploring coffee plantations with an old Irishman in the mountains of Colombia to watching the sun set over the Strait of Gibraltar from the terrace of an ancient Moroccan cafe, this thesis sent Charles and Zane on an elaborate cafe-crawl across ten countries, with stops at a few of

From exploring coffee plantations with an old Irishman in the mountains of Colombia to watching the sun set over the Strait of Gibraltar from the terrace of an ancient Moroccan cafe, this thesis sent Charles and Zane on an elaborate cafe-crawl across ten countries, with stops at a few of the world’s most interesting coffee houses. Some of these cafes, such as the world-renowned Caffé Florian (opened in 1720) and Caffé Greco (1760), are built on long-standing traditions. Others are led by innovators championing high-quality boutique shops, challenging mass production chains such as Starbucks and Tim Hortons. These newer cafes fuel a movement classified as the “Third Wave”. With a foundation gained from specialized courses with Patrick O’Malley, North America’s leading voice in coffee, Zane and Charles conducted first-hand research into the unique coffee preferences of multiple cultures, the emergence and impact of the Third Wave in these countries, and what the future may hold for coffee lovers.

ContributorsJarecke, Zane Micheal (Co-author) / Ferguson, Charles (Co-author) / Eaton, John (Thesis director) / Bonfiglio, Thomas (Committee member) / Dean, W.P. Carey School of Business (Contributor) / Department of Management and Entrepreneurship (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05