Matching Items (115)
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Because metallic aircraft components are subject to a variety of in-service loading conditions, predicting their fatigue life has become a critical challenge. To address the failure mode mitigation of aircraft components and at the same time reduce the life-cycle costs of aerospace systems, a reliable prognostics framework is essential. In

Because metallic aircraft components are subject to a variety of in-service loading conditions, predicting their fatigue life has become a critical challenge. To address the failure mode mitigation of aircraft components and at the same time reduce the life-cycle costs of aerospace systems, a reliable prognostics framework is essential. In this paper, a hybrid prognosis model that accurately predicts the crack growth regime and the residual-useful-life estimate of aluminum components is developed. The methodology integrates physics-based modeling with a data-driven approach. Different types of loading conditions such as constant amplitude, random, and overload are investigated. The developed methodology is validated on an Al 2024-T351 lug joint under fatigue loading conditions. The results indicate that fusing the measured data and physics-based models improves the accuracy of prediction compared to a purely data-driven or physics-based approach.
Created2014-04-01
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High phase order systems have been proposed at the early inception of power transmission engineering, but few direct applications have been made. High phase order transmission should be considered as an alternative in the case of high power density applications. In this article, an analysis of transposition of high phase

High phase order systems have been proposed at the early inception of power transmission engineering, but few direct applications have been made. High phase order transmission should be considered as an alternative in the case of high power density applications. In this article, an analysis of transposition of high phase order overhead transmission lines is presented and voltage unbalance in high phase order systems is considered. Definitions are presented for “fully transposed” and “roll transposed” along with advantages and disadvantages of each. A generalized voltage unbalance factor is introduced and utilized to determine the benefits of transposition. The generalized voltage unbalance factor is compared with three other possible unbalance factors to determine if the generalized voltage unbalance factor is an appropriate indication of unbalance. Exemplary results are presented for 6-phase and 12-phase designs. Conclusions show that the generalized voltage unbalance factor is a good indication of transmission line voltage unbalance and certain configurations may not need full rotation transposition to minimize the unbalance factor. The transposition analysis and voltage unbalance are considerations in the assessment of high phase order as a high power transmission alternative.
Created2014-11-18
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Eigenvalues of the 3D critical point equation (∇u)ν = λν are normally computed numerically. In the letter, we present analytic solutions for 3D swirling strength in both compressible and incompressible flows. The solutions expose functional dependencies that cannot be seen in numerical solutions. To illustrate, we study the difference between

Eigenvalues of the 3D critical point equation (∇u)ν = λν are normally computed numerically. In the letter, we present analytic solutions for 3D swirling strength in both compressible and incompressible flows. The solutions expose functional dependencies that cannot be seen in numerical solutions. To illustrate, we study the difference between using fluctuating and total velocity gradient tensors for vortex identification. Results show that mean shear influences vortex detection and that distortion can occur, depending on the strength of mean shear relative to the vorticity at the vortex center.

Created2014-08-01
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The flexural behavior of epoxies was investigated by performing mechanical tests and applying statistical Weibull theory and analytical methods to the results. The effects of loading systems and environmental conditions were also considered. Three kinds of epoxies were studied: Epon E863, PRI 2002, and PR520. In total, 53 three-point-bending (3PB)

The flexural behavior of epoxies was investigated by performing mechanical tests and applying statistical Weibull theory and analytical methods to the results. The effects of loading systems and environmental conditions were also considered. Three kinds of epoxies were studied: Epon E863, PRI 2002, and PR520. In total, 53 three-point-bending (3PB) Epon E863 samples and 26 3PB PR520 were tested immediately after curing, together with 26 four-point-bending (4PB) PRI2002 samples stored at 60°C and 90% Rh for 48 weeks. The Weibull parameters were estimated using both linear regression and the moments method. The statistical character of the Weibull model leads to uncertainty in the evaluated parameters, even for a large number of experiments. This study analyzed the ratio of flexural strength to tensile strength in bulk epoxy resin polymers. An analytical method previously developed by the authors to study the relationship between uniaxial tension/compression stress-strain curves and flexural load-deflection response was used to obtain the ratio. The results show that the Weibull model overpredicted the aforementioned ratio in different load arrangements.
Created2014-12-01
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Identification of early damage in polymer composites is of great importance. We have incorporated cyclobutane-containing cross-linked polymers into an epoxy matrix, studied the effect on thermal and mechanical properties, and, more importantly, demonstrated early damage detection through mechanically induced fluorescence generation. Two cinnamate derivatives, 1,1,1-tris(cinnamoyloxymethyl) ethane (TCE) and poly(vinyl cinnamate)

Identification of early damage in polymer composites is of great importance. We have incorporated cyclobutane-containing cross-linked polymers into an epoxy matrix, studied the effect on thermal and mechanical properties, and, more importantly, demonstrated early damage detection through mechanically induced fluorescence generation. Two cinnamate derivatives, 1,1,1-tris(cinnamoyloxymethyl) ethane (TCE) and poly(vinyl cinnamate) (PVCi), were photoirradiated to produce cyclobutane-containing polymer. The effects on the thermal and mechanical properties with the addition of cyclobutane-containing polymer into epoxy matrix were investigated. The emergence of cracks was detected by fluorescence at a strain level just beyond the yield point of the polymer blends, and the fluorescence intensified with accumulation of strain. Overall, the results show that damage can be detected through fluorescence generation along crack propagation.
Created2014-09-01
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Description
Fashion is an inherently political and reflective medium for the daily ramblings and revolutions of a society. Much of the time the influence is subtle. Silhouettes and fabrics reflect different stances on conservatism, on sex, on the degrees to which we fetishize luxury, and on infinite other attitudes of an

Fashion is an inherently political and reflective medium for the daily ramblings and revolutions of a society. Much of the time the influence is subtle. Silhouettes and fabrics reflect different stances on conservatism, on sex, on the degrees to which we fetishize luxury, and on infinite other attitudes of an era. Other times the influence is extremely direct, with text printed on the clothing that explicitly articulates a current societal dynamic. I began exploring fashion in 2016, as the country had reached an unprecedented and linguistically weaponized divide.

While taking a fashion technology course under the instruction of Galina Mihaleva, I developed a tracksuit incorporating concealed LED displays that are capable of scrolling customizable text on the sides of the garment. I expanded on this futuristic execution of politically charged clothes by utilizing a more realistic application of the LED technology in the Bouis Vuitton project. This project is a collection of six white vinyl bags with semi-flexible LED displays projecting revolutionary slogans through the vinyl textile.

The bags act as an appropriate housing for technology that is intended for significantly longer use, as bags have a longer lifespan in wardrobes than clothes and return to trend more frequently. The production investment in the technology is more equitable to the investment in the production of a bag and facilitates the wearer’s broadcasting of concise messages. The result is a collection of functional, utilitarian pieces with a clean, futuristic look and a mixed modern and vintage silhouette scrolling pro-revolutionary messages.

Broadcasting the knock-off name ‘BOUIS VUITTON’, I’ve inserted only my first initial into the reputable luxury company and paired it with slogans: ‘EAT THE RICH’ and ‘HEADS WILL ROLL’. The collection articulates a sense of nihilism felt by the youngest generations growing up on the outside of a very exclusive economic and political sphere. Three upcycled vintage luggage pieces evoke associations with the white American upper-class society of the 1960s. The luggage pieces were retrofitted in white vinyl and white-enameled metal fixtures. Three additional soft bags made of the same material reflect a utilitarian style of functional bags on trend with Spring/Summer 2019 streetwear. For the runway presentation of the bags, the models are dressed in navy-colored Dickies boiler suits, white retro-style Fila sneakers, and white ascots reminiscent of the historical male ruffled cravat. The contradictions of iconic silhouettes from both upper and lower-class American fashion history further the juxtaposition of anti-capitalist slogans posted on luxury goods.

Bouis Vuitton: Bags for the Revolution is intended to embody an unapologetic disregard for established wealth and political power in the most public of venues: the sidewalk, the mall, the high and the low-income neighborhoods – wherever people are wearing clothes. Fashion is the modern protest that requires no permit, and the new poster is a luxury bag.
ContributorsViton, Benjamin Douglas (Author) / Sewell, Dennita (Thesis director) / Mihaleva, Galina (Committee member) / School of Art (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description

This paper applies LCA methodology using local variables to assess the environmental impacts of the food grade glass containers that are disposed of on Arizona State University’s Tempe campus throughout their two distinct end-of-life scenarios: glass to be recycled or glass to be sent to the landfill as refuse.

Created2013-05
Description

Many relationships exist between humans and their animal companions. Regardless of the relationship, the costs of pet ownership are more than just veterinary bills and the purchase of pet food. The purpose of this study is to examine the environmental impacts associated with ownership of canus lupus familiaris, more commonly

Many relationships exist between humans and their animal companions. Regardless of the relationship, the costs of pet ownership are more than just veterinary bills and the purchase of pet food. The purpose of this study is to examine the environmental impacts associated with ownership of canus lupus familiaris, more commonly known as the domesticated dog. Since dogs are carnivorous by nature, there has already been significant interest in the ecological ‘pawprint’ of pet food, or the pressure that dog food production exerts on the environment.

This study utilizes Life Cycle Assessment (LCA) to determine the environmental impacts of industrial pet food production and furthermore, pet ownership through nutritional requirements. Additionally, this study aims to examine how pet food type—beef or lamb—can influence greenhouse gas (GHG) emissions. The approach taken by this study is that of a hybrid input-output LCA, combining Economic Input Output (EIO-LCA) data and process-level data to examine how supply chain decisions made by pet food manufactures can affect the ecological ‘pawprint’ of the domestic dog. The EIO-LCA provides an economy-wide lens, whereas, process-based LCAs provide data relevant to specific materials and processes. This approach was used to compare the environmental impacts associated with environmentally friendly supply chain decisions compared to the typical environmental impact of dog food.

Created2013-05
Description

Urban landscaping palm tree waste in the form of palm frond trimmings and bark shavings that is currently handled as municipal solid waste by the City of Phoenix and other major municipalities can be handled in more cost effective ways and lead to reductions in emissions and greenhouse gases. While many cities have

Urban landscaping palm tree waste in the form of palm frond trimmings and bark shavings that is currently handled as municipal solid waste by the City of Phoenix and other major municipalities can be handled in more cost effective ways and lead to reductions in emissions and greenhouse gases. While many cities have green organics collection and diversion programs, they always exclude palm tree waste due to its unique properties. As a result, an unknown tonnage of palm tree waste is annually landfilled as municipal solid waste. Additionally, as the tonnage is unknown, so are the associated emissions, greenhouse gases, and costs. An attributional lifecycle assessment was conducted in the City of Phoenix from the perspective responsibility of the City of Phoenix’s Public Works Department.

Created2013-05
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An increase in population and need to protect the planet has created many initiatives and research goals in developing alternatives methods of fueling. Federal and state policies have provided a push for industries to find ways to of reducing their impact on the environment while maintaining competitiveness. In the sector

An increase in population and need to protect the planet has created many initiatives and research goals in developing alternatives methods of fueling. Federal and state policies have provided a push for industries to find ways to of reducing their impact on the environment while maintaining competitiveness. In the sector of alternative fuels, large policies such as the Renewable Fuel Standards (RFS) in the United States are making goals to reduce vehicular fuel from coal and oil, and focus on alternative fuels such as ethanol and biodiesel. Along with the RFS and other federal policies, states are introducing independent initiatives to promote the use of alternative fuels.

Research has shown that other crops besides corn can feasibly be used to produce ethanol for fuel use. One of the major crops of interest currently is switchgrass (Panicum Virgatum L.) because of its ability to grow under a variety of weather conditions and soil types. Switchgrass does not require as much maintenance as corn and is a perennial grass that can have high yielding fields for up to 9 years.

This report focuses on the impacts from using switchgrass-derived ethanol to meet the state of Arizona’s policy to have government fleet vehicles operating on alternative fuels. The study uses a life cycle assessment (LCA) approach to evaluate 22 million gallons of ethanol produced in Arizona and stored at fueling stations for use. Impacts in land use, global warming, and water quality are evaluated using software tools and databases in Ecoinvent and Simapro.

The results of the study indicate that the cultivation and harvest phase of the process will contribute the most to negative environmental impacts. According to the study, application of heavy nutrient fertilizer and the machinery needed for the additional agriculture have the potential to contribute over 36 million moles of hydrogen and 89 million CTU eq. to the air, soil, and water.

Created2013-05