Showing 331 - 340 of 564 Items
Assessing the Accuracy of Quantum Monte Carlo Pseudopotentials for CO2 Capture in Metal Organic Frameworks
Date: 2021-01-01
Creator: Chloe Renfro
Access: Open access
- As global emissions of CO2 and other greenhouse gases rises, global warming persists as an imminent threat to the environment and every day lives. To reduce greenhouse gas emissions in the atmosphere, there is a need to design materials to separate and capture the different gasses. Current gas capturing technologies lack efficiency and have extensive energy costs. A class of materials for CO2 capture is Molecular Organic Frameworks (MOFs). In order for a MOF to be efficient for this type of separation, the MOF needs to be able to selectively bind to the gas, while also not suffering a high energy cost to remove the gas and reuse the material. Computationally calculated binding energies are used to determine the usefulness of a MOF at capture and separation of a certain gas. Each computational method has its advantages and limitations. In this work, diffusion quantum Monte Carlo is being explored. This paper focuses on the accuracy of recently developed pseudopotentials for DMC use. These pseudopotentials have been tested on smaller molecules but have not been systematically tested for systems such as MOFs. Results from a DMC calculation of Zn-MOF-74 show a binding energy of -18.02 kJ/mol with an error bound of 16.74 kJ/mol. In order to assess the accuracy of the DMC results for binding energies of this magnitude the uncertainty need to be reduced, a subject of ongoing work.
Outlier Detection in Energy Datasets
Date: 2022-01-01
Creator: Stephen Crawford
Access: Open access
- In the past decade, numerous datasets have been released with the explicit goal of furthering non-intrusive load monitoring research (NILM). NILM is an energy measurement strategy that seeks to disaggregate building-scale loads. Disaggregation attempts to turn the energy consumption of a building into its constituent appliances. NILM algorithms require representative real-world measurements which has led institutions to publish and share their own datasets. NILM algorithms are designed, trained, and tested using the data presented in a small number of these NILM datasets. Many of the datasets contain arbitrarily selected devices. Likewise, the datasets themselves report aggregate load information from building(s) which are similarly selected arbitrarily. This raises the question of the representativeness of the datasets themselves as well as the algorithms based on their reports. One way to judge the representativeness of NILM datasets is to look for the presence of outliers in these datasets. This paper presents a novel method of identifying outlier devices from NILM datasets. With this identification process, it becomes possible to mitigate and measure the impact of outliers. This represents an important consideration to the long-term deployment of NILM algorithms.
Unraveling Paradise: Colonialism and Disguise in German Language Literature
Date: 2022-01-01
Creator: Brigita Kant
Access: Open access
- For centuries, the Pacific Islands have been disguised by Europeans through the trope of “island paradise." Despite Europe’s role in bringing colonization and racial oppression to Oceania, the dominant narrative has been that Pacific Islanders lead simple lives, untouched from the complicated aspects of the “modern world.” This narrative has enabled White outsiders to fantasize about the Pacific Islands as a place for personal denial of Western social conventions, simultaneously allowing White European men to fetishize and possess Pacific Island culture and identity. My honors project will closely examine three fictional German language texts- Haimotochare (1819), Der Papalagi (1920), and Imperium (2012)- centered around the exploration German colonial involvement in Pacific Islands. My analysis of these texts will allow for the understanding of how the false narrative of “island paradise” came to be, how it has been embraced and weaponized, and what it means for both German and Pacific Islander post-colonial identity.
Improving Energy Efficiency through Compiler Optimizations
Date: 2021-01-01
Creator: Jack Beckitt-Marshall
Access: Open access
- Abstract--- Energy efficiency is becoming increasingly important for computation, especially in the context of the current climate crisis. The aim of this experiment was to see if the compiler could reduce energy usage without rewriting programs themselves. The experimental setup consisted of compiling programs using the Clang compiler using a set of compiler flags, and then measuring energy usage and execution time on an AMD Ryzen processor. Three experiments were performed: a random exploration of compiler flags, utilization of SIMD, as well as benchmarking real world applications. It was found that the compiler was able to reduce execution time, especially when optimizing for the specific architecture, to a degree that depends on the program being compiled. Faster execution time tended to correlate with reduced energy usage as well, further suggesting that optimizing programs for speed and architecture is the most effective way of decreasing their overall energy usage.
Can Small Donations Have Big Consequences? Candidate Ideology, Small Donations, and Election Results in the 2016 and 2018 Congressional Cycles
Date: 2021-01-01
Creator: Michael Borecki
Access: Open access
- Small donors have provided an increased share of total campaign contributions in the 2016, 2018, and 2020 U.S. federal election cycles, including about $3 billion of the $14.4 billion raised in 2020. Campaign funding is still dominated by an influential set of large donors, but small donations may be the basis for an effective response to the disproportionate amount of “big money” in politics. This study investigates whether candidates who are more extreme perform better with small donors, and then examines the impact of small donations and overall funding on election results. These analyses were performed using linear sum-of-squares regression models. The results in Chapter 2 show that candidates who are more politically-extreme receive more of their funding from small donations, but perform worse in general elections when fundraising is equal. Chapter 3 shows that small donations do not have an impact on candidate performance in general elections more generally, but candidates who outraise their opponent also outperform relative to the district’s partisan lean. However, that effect disappears when looking only at elections decided by less than 10 percent of the vote. These results suggest that small donors are more likely to support candidates who are more politically polarized, but the effects of small donors on the makeup of Congress is marginal at best, at least as far as general election outcomes are concerned. The project concludes by considering reform proposals that seek to broaden the pool of Americans who donate small sums to political candidates.
Investigating the Role of Helicobacter pylori Glycan Biosynthesis in Modulating Host Immune Cell Recognition Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2023-01-01
Creator: Katharine Barrett
Access: Access restricted to the Bowdoin Community
Investigating the Effects of Mixed Solvents on the Excited State Proton Transfer Mechanisms of 8-Amino-2-naphthol This record is embargoed.
- Embargo End Date: 2027-05-19
Date: 2022-01-01
Creator: Alexander Avrom Kreines
Access: Embargoed
Characterizing Toll Receptors in the Mediterranean Cricket Access to this record is restricted to members of the Bowdoin community. Log in here to view.
- Restriction End Date: 2025-06-01
Date: 2022-01-01
Creator: Warsameh Bulhan
Access: Access restricted to the Bowdoin Community
"Possessive gentleness": Insecure Attachments in American Literature
Date: 2022-01-01
Creator: Ella Pearl Crabtree
Access: Open access
- “‘Possessive Gentleness’: Insecure Attachments in American Literature” applies psychological attachment theory to works of American Literature. Each novel examined—Uncle Tom’s Cabin (1851), Dred: A Tale of the Dismal Swamp (1856), and The Minister’s Wooing (1859) by Harriet Beecher Stowe, The Third Generation (1954) by Chester Himes, and The Bluest Eye (1970) by Toni Morrison—describes the forces behind insecure attachment relationships between child characters and their caregivers. The first chapter of this project focuses on Stowe’s anti-slavery novels. It argues that the institution of slavery is in conflict with Christianity in these works, because it impedes disinterestedly benevolent mothering and disrupts secure attachments. The second chapter analyzes The Third Generation, and suggests that colorism in the black community is the cause of insecure attachments in Himes’ work. The third and final chapter examines The Bluest Eye, and presents sympathy, as embodied by the novel’s narrator, as a potential remedy for insecure parent-child attachments. Together, these texts elucidate how societal forces (e.g. colorism, poverty) intrude upon the family structure and destabilize parent-child attachments. Optimistically, however, they also suggest that improved parent-child attachments might function as a vehicle of broader social change.
Characterization of the ELMO2 Protein that Mediates Cell Adhesion in Arabidopsis thaliana
Date: 2022-01-01
Creator: Devaki Rajiv
Access: Open access
- The binding of adjacent cells to one another, or cell adhesion, is critical for the growth and development of multicellular organisms. In plant cells, much evidence suggests that the amount and modification of pectin in the cell wall largely determines how well cell adhesion occurs. ELMO1 is a Golgi protein involved in pectin-mediated cellular adhesion, and mutations in ELMO1 lead to disrupted cell organization in Arabidopsis. ELMO1 is predicted to be a scaffold for pectin biosynthesis enzymes, and thus its absence leads to the adhesion-defective phenotype of elmo1-/- plants. There are four other ELMO homologues (ELMO2,3,4 and 5) which remain to be characterized as to their function and role in cell adhesion. This thesis focuses on the characterization of ELMO2, which has 79% amino acid similarity with ELMO1. A genetic analysis that evaluated elmo2 double mutants revealed that ELMO2 and ELMO1 have redundant functions. elmo1-/-/2-/- double mutants, but not elmo2-/- or elmo1-/- single mutants, have reduced tensile strengths. While elmo1-/- phenotypes are most pronounced in liquid media, they are partially rescued by growth on agar, suggesting a role of turgor in maintaining cell adhesion. Like ELMO1, ELMO2-GFP colocalizes with Golgi markers. The results suggest that like ELMO1, ELMO2 also functions as a scaffold for pectin biosynthesis enzymes in the Golgi.