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Description
Greenhouse gas (GHG) emissions cause climate change, and if the world does not lower its GHG emissions soon, it will cause irreversible damage that will have overwhelmingly negative cascading effects on the entire planet (Mann & Kump, 2008). Up to 47% of the United States GHG emissions are the result of energy used to produce, process, transport, and dispose of the food we eat and the goods that we consume (US EPA, 2009). The linear-economy status quo does nothing to slow down climate change because it puts resources into landfills. This project promotes a circular economy which combats climate change by reusing resources that are at the end of their life cycle, e.g., food waste soil. The project was a month-long compost competition at an apartment building in Phoenix, AZ that houses 194 residents. The apartment building, Urban Living 2 (UL2), is subsidized housing owned by Native American Connections (NAC), a non-profit organization. The project’s main objective was to increase waste diversion. This was done through composting and improving zero-waste capacity. The compost competition included activities to change community behavior such as private and public commitments, a community barbecue, a movie night (which replaced a planned field trip), and a visioning meeting. By the end of the project, 22% of the tenants were composting. Over a year-long period, this equates to a diversion of, 6000 pounds from the landfill and 1.59 metric tons of Carbon Dioxide equivalent (MTCO2E). The waste diversion increased from 28% to 38%. Tenant participation trended upwards during the project and as the social norm develops over time, more tenant participation is expected even after the competition is over. The six indicators that were used to determine the zero-waste capacity, collectively went up by 1.24 points on a five-point scale. This project will be used as a model for NAC for its other 16 properties in the Valley.
ContributorsVelez, Daniel (Author)
Created2017-04-10
Description
The purpose of this paper is to identify the absence of sustainability teachings within our private school systems, introduce a program for the school systems to incorporate into existing curriculum, and present the process that would be needed to be followed for introduction of this program. There is a growing interest in the topic of sustainability and how it potentially will affect the next generations. Today some large companies and even some countries around the world are engaging in sustainability practices. Currently this is a very small piece of action regarding what needs to take place to hope to promote change around the world. Layering sustainable teachings and practices into children in their formidable years through graduation from high-school will bring about individuals that incorporate sustainable living into their everyday personal and professional lives. Repeating this practice generation after generation will ensure a sustainable planet.
ContributorsJanner, Brian D. (Author)
Created2018-04-24
Description
Girl Scouts – Arizona Cactus-Pine Council is a mission driven organization that aims to help build the leaders of tomorrow. Girls in Girl Scouts-Arizona Cactus-pine are served through mission building programs that aim to build girls of courage confidence and character who make the world a better place (Girl Scouts, 2017). The intention of my sustainability engagement initiative was to ask staff to take part in a three-phased program that encouraged them to think differently. The initiative asked them to look at how, as an organization they can work to improve their sustainability habits. Tasking them to be just as impactful as the girl members that are served through Girl Scouting. However, as planning progressed towards implementation, plans were put on hold as the organization restructured due to a major culture shift outside the organization. Sustainability still remains a focus, and the engagement plan will be put into effect at a later time.
ContributorsPontius, Cristi (Author)
Created2018-04-13
Description
Greater cross-disciplinary collaboration between the fields of sustainability and clinical psychology could lead to improved outcomes for both. Moreover, some forms of mental disorder, such as PTSD and Moral Injury, constitute serious challenges that require the attention of sustainability’s interdisciplinary, systems-focused, solutionsoriented approach. My research frames the impacts of combat-related psychological trauma on military veterans as a sustainability problem according to criteria put forward by Arnim Wiek’s Transformational Problem Solving framework. I also provide a review of studies demonstrating the treatment benefits of agricultural therapy for veterans diagnosed with PTSD or symptoms associated with Moral Injury. I then describe my own efforts investigating the connection between trauma and sustainability using survey measurements, interviews, and participant observation onsite at Growing Veterans farm in Mt. Vernon, Washington. The results strongly suggest that sustainable agricultural can be of powerful clinical benefit to traumatized veterans and that sustainable behaviors and values in general increased as trauma symptoms decreased. More broadly, the project indicates that slight shifts in how we approach solution formulation and how we articulate and disseminate sustainability messages could have profound positive effects on the sustainability’s success.
ContributorsGabriele, Adam (Author) / Hirt, Paul (Contributor) / Cloutier, Scott (Contributor) / Valdez, Herendira (Contributor)
Created2018-03-27
Description
Blockchain, the technology behind the worldwide-known cryptocurrency Bitcoin, offers a new set of potential advantages and opportunities that various industries and institutions could use to enhance their processes. Although most research and development on blockchain has focused on applications for cryptocurrencies and the finance industry, relatively few analyses and assessments have been conducted on how it could provide tools to address social and environmental issues. This research, using interviews, literature review and examples of blockchain applications, explores how this technology can be employed to address sustainability issues under the framework of three UN Sustainable Development Goals: 2. Zero Hunger, 7. Affordable and Clean Energy, and 14. Life Below Water. The analysis shows that blockchain has the potential to support solutions to sustainability problems that need efficient traceability, trust, a unique ID, transparency, or a highly secure payment system. However, the technology should not be mistaken for a panacea for addressing sustainability issues in its current state because it is not yet mature and has not been sufficiently tested. Expansion of blockchain as an effective tool for helping solve sustainability challenges will require a greater understanding of the governance of blockchain, its scalability and its potential unintended consequences for the technology to become properly integrated into the decision-making progress.
ContributorsRomo, Maximiliano (Author) / Melnick, Robert (Contributor, Contributor) / Maynard, Andrew (Contributor) / Boscovic, Dragan (Contributor)
Created2019-04-17
Description
Description
By avoiding vehicle idling for three minutes every day of the year can reduce 1.4 million metric tons annually, which is equivalent to taking 320,000 cars off the road for the entire year (Canada.ca, 2016). The Automobile Idle Reduction Program (AIRP) is an outreach initiative to prevent carbon emissions from being released into the air by automobiles idling in Maricopa County. The initiative establishes a campaign to promote behavioral changes that target high idling industries: freight and delivery, schools and drive- thru facilities.
Background
Globally, carbon emissions negatively alter the air we breathe and is a leading cause in climate change. These problems adversely affect the global environment and human health. Additionally, they have cancer causing agents in the particulate matter. Unfortunately, over the years, Maricopa County has failed to meet air quality standards for particulate matter pollution which effects the health of residents. By not meeting the air quality standards, Maricopa County can receive sanctions and the Environmental Protection Agency can reject Arizona’s State Implementation Plan. This looming threat can financially impinge the economy of Maricopa County, potentially costing taxpayers a substantial increase in taxes.
Strategy and Solution
To battle the creation of carbon emissions and particulate matter, AIRP has developed a strategy for each industry. In partnership with the Maricopa County Air Quality Department, AIRP will introduce the freight and delivery companies to the Diesel Emission Reduction Act (DERA) Grant promotion to facilitate and fiscally assist with changing older diesel engines into higher efficiency engines that burn cleaner. Provide educators a fifth to eighth grade state approved education program to teach students the importance of vehicle idling reduction at no cost. And work with community organizations to offer a discount at their stores for those patrons who choose to turn their engine off and order inside, rather than idling in the drive-thru facilities. The campaign will market the interest of AIRP to the general public through purposefully placed billboards, light rail wraps, social media pushes, handouts and vinyl stickers.
By avoiding vehicle idling for three minutes every day of the year can reduce 1.4 million metric tons annually, which is equivalent to taking 320,000 cars off the road for the entire year (Canada.ca, 2016). The Automobile Idle Reduction Program (AIRP) is an outreach initiative to prevent carbon emissions from being released into the air by automobiles idling in Maricopa County. The initiative establishes a campaign to promote behavioral changes that target high idling industries: freight and delivery, schools and drive- thru facilities.
Background
Globally, carbon emissions negatively alter the air we breathe and is a leading cause in climate change. These problems adversely affect the global environment and human health. Additionally, they have cancer causing agents in the particulate matter. Unfortunately, over the years, Maricopa County has failed to meet air quality standards for particulate matter pollution which effects the health of residents. By not meeting the air quality standards, Maricopa County can receive sanctions and the Environmental Protection Agency can reject Arizona’s State Implementation Plan. This looming threat can financially impinge the economy of Maricopa County, potentially costing taxpayers a substantial increase in taxes.
Strategy and Solution
To battle the creation of carbon emissions and particulate matter, AIRP has developed a strategy for each industry. In partnership with the Maricopa County Air Quality Department, AIRP will introduce the freight and delivery companies to the Diesel Emission Reduction Act (DERA) Grant promotion to facilitate and fiscally assist with changing older diesel engines into higher efficiency engines that burn cleaner. Provide educators a fifth to eighth grade state approved education program to teach students the importance of vehicle idling reduction at no cost. And work with community organizations to offer a discount at their stores for those patrons who choose to turn their engine off and order inside, rather than idling in the drive-thru facilities. The campaign will market the interest of AIRP to the general public through purposefully placed billboards, light rail wraps, social media pushes, handouts and vinyl stickers.
ContributorsWeston-Smith, Kristen (Writer of accompanying material)
Created2020-05-13
Description
An efficient thermal solver is available in the CMC that allows modeling self-heating in the electrical simulations, which treats phonons as flux and solves the energy balance equation to quantify thermal effects. Using this solver, thermal simulations were performed on GaN-HEMTs in order to test effect of gate architectures on the DC and RF performance of the device. A Π- gate geometry is found to suppress 19.75% more hot electrons corresponding to a DC power of 2.493 W/mm for Vgs = -0.6V (max transconductance) with respect to the initial T-gate. For the DC performance, the output current, Ids is nearly same for each device configuration over the entire bias range. For the RF performance, the current gain was evaluated over a frequency range 20 GHz to 120 GHz in each device for both thermal (including self-heating) and isothermal (without self-heating). The evaluated cutoff frequency is around 7% lower for the thermal case than the isothermal case. The simulated cutoff frequency closely follows the experimental cutoff frequency. The work was extended to the study of ultra-wide bandgap material (Diamond), where isotope effect causes major deterioration in thermal conductivity. In this case, bulk phonons are modeled as semiclassical particles solving the nonlinear Peierls - Boltzmann transport equation with a stochastic approach. Simulations were performed for 0.001% (ultra-pure), 0.1% and 1.07% isotope concentration (13C) of diamond, showing good agreement with the experimental values. Further investigation was performed on the effect of isotope on the dynamics of individual phonon branches, thermal conductivity and the mean free path, to identify the dominant phonon branch. Acoustic phonons are found to be the principal contributors to thermal conductivity across all isotope concentrations with transverse acoustic (TA2) branch is the dominant branch with a contribution of 40% at room temperature and 37% at 500K. Mean free path computations show the lower bound of device dimensions in order to obtain maximum thermal conductivity. At 300K, the lowest mean free path (which is attributed to Longitudinal Optical phonon) reduces from 24nm to 8 nm for isotope concentration of 0.001% and 1.07% respectively. Similarly, the maximum mean free path (which is attributed to Longitudinal Acoustic phonon) reduces from 4 µm to 3.1 µm, respectively, for the same isotope concentrations. Furthermore, PETSc (Portable, Extensible Toolkit for Scientific Computation) developed by Argonne National Lab, was included in the existing Cellular Monte Carlo device simulator as a Poisson solver to further extend the capability of the simulator. The validity of the solver was tested performing 2D and 3D simulations and the results were compared with the well-established multigrid Poisson solver.
ContributorsAcharjee, Joy (Author) / Saraniti, Marco (Thesis advisor) / Goodnick, Stephen (Committee member) / Thornton, Trevor (Committee member) / Wang, Robert (Committee member) / Arizona State University (Publisher)
Created2024
Description
Amidst mounting global crises spanning environmental, social, and economic domains, sustainability education has emerged as a vital pathway toward a thriving future. However, despite its promise, the concept of sustainability often remains superficial, leaving educators ill-equipped to address its complexities. While efforts to integrate sustainability into education are underway, critical pedagogy, a crucial tool for fostering social change, is notably absent from instructional practices. This action research project utilized critical pedagogy to design and implement a critical professional development (CPD) workshop within a larger fellowship program to center justice within sustainability in both content and pedagogical approach. As a result, participants’ definitions and understandings of sustainability increased across all measurements of extent, breadth, and depth. Specifically, participants redefined collaborative relationships and more prominently included notions of justice and equity in their conceptualizations of sustainability and sustainability education. The use of critical pedagogy encouraged teachers to analyze intersectional oppressive systems and fostered a new, critical perspective on sustainability. In their own educational designs, participants demonstrated an intention to model elements of critical pedagogy, such as dialogic action and permeable content. Finally, in alignment with the intended outcomes of CPD, participants developed cooperative space for co-learning, built unity, shared leadership, and felt confident implementing their own professional development to address context-specific concerns. By using critical pedagogy in sustainability education, the workshop participants prioritized deep and caring relationships which fostered empathic engagement with the intersectional and often dehumanizing systems that have led to interconnected global crises. The results indicated that using CPD as a framework could be effective in teacher professional development for sustainability as a design and implementation tool to center critical work that examines systemic issues of injustice and exploitation against both humans and our planet.
ContributorsCashion, Molly Elise (Author) / Judson, Eugene (Thesis advisor) / Casanova, Carlos (Committee member) / Goebel, Janna (Committee member) / Boyce, Ayesha (Committee member) / Arizona State University (Publisher)
Created2024
Description
Recent advancements in communication standards, such as 5G demand transmitter hardware to support high data rates with high energy efficiency. With the revolution of communication standards, modulation schemes have become more complex and require high peak-to-average (PAPR) signals. In wireless transceiver hardware, the power amplifier (PA) consumes most of the transceiver’s DC power and is typically the bottleneck for transmitter linearity. Therefore, the transmitter’s performance directly depends on the PA. To support high PAPR signals, the PA must operate efficiently at its saturated and backoff output power. Maintaining high efficiency at both peak and backoff output power is challenging. One effective technique for addressing this problem is load modulation. Some of the prominent load-modulated PA architectures are outphasing PAs, load-modulated balanced amplifiers (LMBA), envelope elimination and restoration (EER), envelope tracking (ET), Doherty power amplifiers (DPA), and polar transmitters. Amongst them, the DPA is the most popular for infrastructure applications due to its simpler architecture compared to other techniques and linearizability with digital pre-distortion (DPD). Another crucial characteristic of progressing communication standards is wide signal bandwidths. High-efficiency power amplifiers like class J/F/F-1 and load-modulated PAs like the DPA exhibit narrowband performance because the amplifiers require precise output impedance terminations. Therefore, it is equally essential to develop adaptable PA solutions to process radio frequency (RF) signals with wide bandwidths. To support modern and future cellular infrastructure, RF PAs need to be innovated to increase the backoff power efficiency by two times or more and support ten times or more wider bandwidths than current state-of-the-art PAs. This work presents five RF PA analyses and implementations to support future wireless communications transmitter hardware. Chapter 2 presents an optimized output-matching network analysis and design to achieve extended output power backoff of the DPA. Chapters 3 and 4 unveil two bandwidth enhancement techniques for the DPA while maintaining extended output power backoff. Chapter 5 exhibits a dual-band hybrid mode PA design targeted for wideband applications. Chapter 6 presents a built-in self-test circuit integrated into a PA for output impedance monitoring. This can alleviate the PA performance degradation due to the variation in the PA's output load over frequency, process, and aging. All RF PAs in this dissertation are implemented using Gallium Nitride (GaN)-based high electron mobility transistors (HEMT), and the realized designs validate the proposed PAs' theories/architectures.
ContributorsRoychowdhury, Debatrayee (Author) / Kitchen, Jennifer (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Ozev, Sule (Committee member) / Aberle, James (Committee member) / Arizona State University (Publisher)
Created2024
Description
Engineering polymers are critical for contemporary high-performance applications where toughness, thermal stability, and density are at a premium. These materials often demand high-energy processing conditions or highly reactive monomers that hold negative impacts on human and environmental health. Thus, this work serves to remediate the negative impacts of engineering polymer synthesis by addressing toxicity and processing at the monomer level, while maintaining or exceeding previous thermomechanical and stimuli-responsive performance. Polyurethanes (PUs) represent a class of engineering polymers that possess highly modular properties due to the diverse monomer selection available for their synthesis. The efficient reaction between isocyanates and hydroxyls impart stellar properties and flexible processing modalities, however recent scrutiny regarding the toxicity of the isocyanate precursors has driven the search for non-isocyanate polyurethane (NIPU) pathways. The advancement of bis-carbonylimidazolide (BCI) monomers for the synthesis of NIPU thermoplastics and foams is thoroughly investigated in this work. Remarkably, a novel decarboxylation pathway for BCI monomers controlled by catalyst loading enabled in-situ CO2 generation during crosslinking with trifunctional amines, and resulted in a facile synthetic route for NIPU foams. Further explorations into catalyst considerations revealed Dabco® 33-LV as a suitable mechanism for controlling reaction times and careful selection of surfactant concentration provided control over pore size and geometry. This led to a library of flexible and rigid NIPU foams that displayed a wide range of thermomechanical properties. Furthermore, sequestration of the imidazole byproduct through an efficient Michael reaction identified maleimide and acrylate additives as a viable pathway to eliminate post-processing steps resulting in NIPU foam synthesis that is amenable to current industrial standards. This route held advantages over the isocyanate route, as condensate removal drove molecular weight increase and ultimately achieved the first reported phase separation behavior of a NIPU thermoplastic containing a poly(ethylene glycol) soft segment. Furthermore, sustainable considerations for engineering polymers were explored with the introduction of a novel cyclobutane bisimide monomer that readily installs into various polymeric systems. Direct installation of this monomer, CBDA-AP-I, into a polysulfone backbone enabled controlled photo-cleavage, while further hydroxy ethyl functionalization allowed for incorporation into PU systems for photo-cleavable high-performance adhesive applications.
ContributorsSintas, Jose Ignacio (Author) / Long, Timothy E (Thesis advisor) / Sample, Caitlin S. (Committee member) / Jin, Kailong (Committee member) / Arizona State University (Publisher)
Created2024