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Publication Defining and Designing an Ethical Approach to Generative Artificial Intelligence in Text-to-Image Modeling(2024) Goodman, DrakeThis paper addresses the ethical concerns that generative artificial intelligence (AI) in text-to-image modeling poses, specifically in protecting social equality and against discrimination. It first defines AI and explains the focus on generative AI. It then discusses the emergence of generative AI modeling, as well as prominent players in the generative AI text-to-image space. After explaining different ethical questions that have arisen in response to the rapid deployment of the technology, this paper establishes an ethical claim for why AI developers need to design these models to protect social equality and reduce stereotypes. This occurs in two ways. The first is explaining how the biases and stereotypes present in generative AI differ from the world before this technology existed. The second is establishing why amplifying stereotypes and biases is wrong, as well as why generative AI developers specifically have a moral obligation to protect social equality.Publication Tritium Removal from CANDU Reactors(2024-06-18) Siefken, Ella; Lu, Jason; Ngo, PhuongWithin the next 50 years, the global demand for tritium will increase with the startup of fusion reactors, while the global supply (currently estimated at 25 kg) slowly dwindles due to its short half-life. Heavy water moderator from CANDU reactors is the only large scale source of tritium that can meet the rising demand. Only two tritium removal facilities are in operation worldwide, while the development of a third is uncertain. Currently, at the Bruce Nuclear Generation Station in Ontario, Canada, the tritiated heavy water is stored and transported to the Darlington Tritium Removal Facility, posing logistical challenges and risks of radioactive exposure during storage and transport. We propose the implementation of a tritium removal facility at the Bruce Nuclear Generation Station to continuously extract tritium from heavy water moderator from the four Bruce C units currently in the early stages of development. The heavy water would undergo electrolysis before being cooled to cryogenic temperatures of about 26–27 K and fed through a cryogenic distillation cascade that would produce gaseous tritium of 99.9% purity at a rate of 178 grams per year. Continuous tritium extraction would also maintain the radioactivity of the CANDU reactor moderator under 10 Ci/kg, an essential benchmark for reactor and environmental safety. Compared to existing tritium removal facilities, this process presents three novel advantages: 1) Direct electrolysis pre-treatment that foregoes the use of complex catalysts; 2) A thermally linked design that utilizes helium refrigerant to provide heating and cooling duty; 3) Optimized cryogenic distillation system that provides tritium product of higher purity that other similar processes. Assuming a tritium sale price of $30,000 per gram and a plant lifetime of 35 years, the tritium removal process presented is not profitable, with an ROI of -6.13% in the third production year and a negative IRR. However, this process design is highly valuable as tritium prices are expected to surge in the next decade as fusion plants reach technological readiness and require tritium to fuel fusion reactors.Publication Is the Growing Burden of Non-Communicable Diseases in India Preventable?(2024-06-19) Gaiha, Raghav; Kulkarni, Vani S.; Unnikrishnan, VidhyaNon-Communicable Disease (NCD) morbidity and mortality as shares of total morbidity and mortality have risen steadily in India and projected to surge rapidly. In 1990, NCDs accounted for 40% of all Indian mortality and are now projected to account for three quarters of all deaths by 2030. Currently, cardiovascular diseases, cancer, respiratory illness, and diabetes are the leading causes of death in India, accounting for almost 50% of all deaths. Underlying these rising shares are growing risks that are common to several NCDs. NCDs are chronic in nature and take a long time to develop. They are linked to aging and affluence and have replaced infectious diseases and malnutrition as the dominant causes of ill health and death in much of the world including India. Some NCDs cause others and create clusters of co-morbid conditions (e.g., diabetes can lead to kidney failure and blindness). Old-age morbidity is a rapidly worsening curse in India. The swift descent of the elderly in India (60 years +) into non-communicable diseases (e.g., cardiovascular diseases, cancer, chronic respiratory diseases, and diabetes) could have disastrous consequences in terms of impoverishment of families, excess mortality, lowering of investment and deceleration of economic growth. Indeed, the government must deal simultaneously with the rising fiscal burden of NCDs and substantial burden of infectious diseases. The present study seeks to answer three questions: Why has the prevalence of two NCDs, diabetes and heart diseases risen in recent years? Given the surge in these diseases, whether social protection policies and restructuring of medical services can mitigate such surges in the near future? A related but equally important concern is whether lifestyle and dietary changes could be induced to further prevent the rising burden of these NCDs. Our analysis is based on the only all-India panel survey-India Human Development survey that covers 2005 and 2012. This survey was conducted jointly by University of Maryland and National Council of Applied Economic Research, New Delhi. A robust econometric methodology-specifically, 2SLS- is used to address the endogeneity of key explanatory variables. The results here stress the need to make sure that pension and healthcare reforms are accompanied by greater awareness, expansion of old age pensions and public hospitals, and effective regulation of both public and private hospitals. Key words: NCDs, Diabetes, Heart diseases, Old age and other pensions, Hospitals, IndiaPublication Production of ATJ-SPK From Ethanol Feedstock(2024-06-18) Sheldon, Jacob; Stosich, Corbyn; Walker , MitchIn 2021, the U.S. government released the Sustainable Aviation Fuel Grand Challenge, which pledges a goal of supplying sustainable aviation fuel (SAF) to meet 100% of fuel demand by 2050. SAF currently makes up less than 0.1% of the total jet fuel industry and is nearly twice as expensive as jet fuel sold from a typical refinery (FAA, 2022). There are currently nine SAF production pathways that have been approved by ASTM, one of which is known as Alcohol-to-Jet-Synthetic Paraffinic Kerosene (ATJ-SPK). A 2019 white paper by Gevo outlines the principles of ATJ-SPK, where starchy alcohols are converted to isobutanol, which is then converted to paraffinic kerosene through well-established processes of dehydration, oligomerization, and hydrogenation (Gevo, 2019). An ATJ-SPK plant was designed with the intention of exploring the environmental and economic viability of a pure ethanol feed. To date, most developed ATJ-SPK plants have an isobutanol feed. The designed plant follows the three established steps: dehydration, oligomerization, and hydrogenation. For ethanol dehydration, Ni-HZSM-5 catalyst was used to convert ethanol to ethylene. The oligomerization and hydrogenation steps were both accomplished using two reactors in series with two unique catalysts. This design decision was made to target reactions in the C9-C16 range, ideal for kerosene jet fuel. For the first and second oligomerization reactors, Ni-H-β and Al2O3/SiO3 catalysts were used, respectively. Feed to the hydrogenation reactors consisted of mostly C8-C17 olefins, where a Ni-C catalyst was used in the first reactor, and a 0.3% Pt/Al2O3 was used in the second reactor. Paraffins were separated by size into SAF, diesel, and gasoline. Analysis revealed the economic viability of the designed ethanol feed ATJ-SPK process is highly dependent on the Sustainable Aviation Fuel Credit created by the Inflation Reduction Act. The credit gives $1.25 per gallon of SAF sold, given that the SAF has a 50% reduction in lifetime greenhouse gas emissions. The following process reduces GHG emissions by almost exactly 50%, putting the process at risk for not receiving the SAF tax credit if an unexpected source of emissions is discovered. Furthermore, the SAF tax credit expires in 2025, so there is little long-term economic viability of the designed process. With the discontinuation of government incentives, achieving the ambitious 2050 emissions goal for the aviation industry becomes even more challenging. If the United States is committed to these targets, additional tax incentives will likely be essential. The following design can be used as a baseline for future ethanol feed ATJ-SPK processes, and may prove viable if there are additional economic incentives established for SAFs as the 2030, 2040, and 2050 goals of the aviation industry to reduce emissions become a top environmental priority.Publication Hydrogen Production from Efficient Two-Step Water Splitting(2024-06-18) Bagchi, Rohan; Ghosh, Andreas; Murphy, KaraThe demand for renewable energy sources such as hydrogen is projected to increase in the next few decades as the world turns its sights towards reducing the effects of climate change. Hydrogen has recently been considered for use in the automobile industry as a power source for fuel cell vehicles because of its high energy density by mass. The greenest form of hydrogen production is through water electrolysis. Traditional water electrolysis, however, requires a membrane, which lowers efficiency and raises costs and safety risks. In this report, we design a process for two-step splitting of water by rotating cycles of electrochemical production of hydrogen and thermochemical production of oxygen without the use of a membrane. The process produces 28,000 U.S. tons of hydrogen per year with a co-product of 222,000 U.S. tons of oxygen per year. The electricity to power the electrolysis and other process units is sourced from solar energy. With a selling price of $1.02/lb of hydrogen - based on current prices for grey hydrogen, a selling price of $0.04/lb of oxygen, and a tax credit of $1.46/lb for the production of green hydrogen, the plant would achieve a return on investment of -1.87%, an internal rate of return of 34%, and a net present value of $152 million. In the best-case scenario where oxygen can be sold at a higher price of $0.30 for medical uses, the plant becomes much more profitable with an IRR of 67% and an ROI of 44%. The process’ voltage efficiency of 91.0% and HHV efficiency of 81.3% make it competitive with the best electrolysis technologies used in industry. Overall, the process provides one pathway towards a large-scale hydrogen economy.