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An Accessible Maize Sheller for the Post-Harvesting Challenges of Small Farmers in Kenya
No full textMaize is a critical staple crop in Kenya, yet post-harvest processing remains inefficient for small-scale farmers who cannot afford industrial shelling equipment. Manual shelling is labor-intensive and time-consuming, often taking over nine hours per 100 kg bag of maize. While mechanized stationary shellers are faster, their bulk and immobility force farmers to transport their harvests—incurring costs that consume up to 89% of potential profits.
This project developed and tested a low-cost, portable maize sheller tailored to the constraints and priorities of smallholder farmers in rural Kenya. Two prototypes were designed, built, and evaluated. The first achieved high shelling efficiency (97.3%) and processing speeds of 18.9 seconds per kilogram but required manual stabilization of each cob. The second prototype introduced an inner-outer shelling mechanism that enabled hands-free operation and supported continuous feeding. While its average shelling efficiency (89%) fell slightly below the target of 95%, it marked a significant step toward improving usability and throughput.
Design decisions were informed by feedback from agricultural experts and field testing with 13 farmers in Migori County, Kenya. User input emphasized portability, ease of use, and minimal post-shelling cleaning. The project demonstrates the viability of an accessible shelling device that could substantially reduce labor, improve efficiency, and enhance profitability for smallholder farmers. With further refinement, this solution could be adapted for broader deployment in similar agricultural contexts.Mechanical Engineering S
The View from Down Here: The Airfield Beyond Empire
No full textNorth Field, a World War II-era airfield on the island of Tinian, embodies the enduring impact of military infrastructure on land, people, and memory. Once the busiest airfield in the world, its relentless flatness and placelessness reflect a larger system of logistical landscape left frozen in time.
“The View from Down Here” critiques the U.S. Department of Defense as the world’s most prolific landscape architect, shaping global terrains through both infrastructural transformation and its representation. Using archival and field research, counter mapping, and speculative design, this project unsettles the airfield’s rigid flatness. Taking on North Field’s four runways, site-specific interventions expose buried histories still held in the landscape, re-presenting the infrastructure of empire at a multitude of scales and temporalities, where the present intertwines with the past and future. This project re-imagines technical landscapes as sites of remembrance, resistance, and life; asking the question―what happens after empire and wasteland?Department of Landscape Architectur
Paradise in the Periphery: Martial Law, Occupation and American Empire in Hawaii, 1941-1950
No full textThis thesis argues that Hawaii’s years under martial law from 1941 to 1944—extended until 1945—should be historiographically understood as a military occupation by situating Hawaii within amongst other occupations, including the French in Algeria, Japan in the Aleutians, the British in Scotland, the Boers in Southern Africa, Russia in Donbas, and Israel in Sinai. This study demonstrates how Hawaii's experience aligns with broader historical patterns of occupation. It contends that occupation is best understood through structural and material realities rather than legal recognition alone.
While the military government justified martial law as a wartime necessity, this argument, based on Ex Parte Milligan, was only legally sound in the immediate aftermath of December 7, 1941. However, political rhetoric extended necessity beyond its legal limits, persisting even after the U.S. victory at Midway rendered the justification obsolete. The thesis explores how military occupations avoid classification as such when sovereignty is ambiguous, as seen in Hawaii, the Philippines, and Scotland where territories are framed as internal matters rather than sites of belligerent confrontation. Recognizing Hawaii’s martial law years as an occupation challenges existing scholarship, particularly on statehood, where its influence has been overlooked.
Hawaii’s transition from democracy to authoritarian rule under martial law catalyzed a shift in political consciousness, fueling demands for self-determination in response to the suppression of civil liberties and military overreach. This study highlights key acts of resistance, including labor activism, Japanese American veterans' advocacy, and political actors who contested the legal foundations of martial law. In doing so, it advances our understanding of Hawaii’s trajectory toward statehood.
Ultimately, this study contributes to a deeper understanding of the American Empire and its racialized imperialism by framing Hawaii’s martial law period within the historiography of occupation. In doing so, it not only recontextualizes Hawaii’s path to statehood and complications the discussions of military rule, sovereignty, and U.S. expansionism.Extension Studie
(Dis)Connected: Political Polarization, Social Connection, and Social Trust in the United States
No full textThis thesis examines the relationship between political polarization, social connection patterns, and social trust in the United States through a multi-scale quantitative analysis. Using county-level data from the 2016 and 2020 presidential elections, social connection data from Meta, demographic information from the US Census, and data on trust from Gallup surveys, I analyze how these data influence five specific dimensions of polarization: spread, dispersion, divergence, group distinctness, and size parity. My findings reveal that within-county social connectedness is significantly associated with increased dispersion polarization, suggesting that denser social networks support more varied political attitudes. My analysis of cross-county social connections showed that stronger connections between counties slightly decrease overall polarization measures but also increase political similarity between connected counties. These relationships are strongly moderated by geographic and demographic factors, with distance, education, and racial diversity playing particularly important roles. Contrary to expectations, national data (though limited) show that some measures of polarization and all measures of institutional trust increased simultaneously between 2016 and 2020, challenging the hypothesis that polarization necessarily erodes trust. These findings highlight the importance of examining polarization as a multidimensional construct and of considering the multiple scales at which social connections operate to influence political environments.Extension Studie
Technology and Transition
No full textWhat role should emerging technologies such as carbon removal and solar geoengineering play in our response to the climate crisis? To critics, these technologies fail to address the root cause of climate change and allow wealthy nations to evade their climate responsibilities. To supporters, these technologies could make it easier to meet climate targets and even contribute to making the energy transition fairer. Indeed, carbon removal is widely considered to be a necessary component of the energy transition. This dissertation aims to advance this debate by unearthing and critiquing a web of normative and conceptual errors that confuse and constrain it. In doing so, this work contributes to broader questions concerning the relationship between technology, fairness, efficiency, and growth.Philosoph
A Proposed Framework for Optimally Managing Fisheries
No full textA fishery is an interconnected marine ecosystem where people fish for commercial and recreational purposes. As fishermen continue to fish, the total fish stock depletes, stressing marine ecosystems. Furthermore, climate change and other external environmental stressors continue to damage marine habitats, making fish more prone to dying or migrating to different areas in search of food. This alters the species composition within fisheries. The dynamic nature of these fisheries suggests that fishery managers must find ways to create models that account for increases or decreases in particular fish species and how these changes will affect the state of the current marine ecosystem. To preserve these natural ecosystems and ensure that people can continue to survive and thrive, institutional and governing bodies need to understand how to optimize the yield within these multispecies fisheries. One of the primary issues fishery managers are currently struggling with is the failure and resistance to modeling multispecies fisheries. This resistance stems from data gaps, resource limitations, management inertia, familiarity with single species models, and social constraints that inhibit institutional bodies from addressing the multispecies issue. This paper aims to create a multispecies theoretical model that encompasses interactions between species, which policymakers can rely on to build more precise and effective models. The theoretical framework proposed by this paper calls for the elimination of banking quotas. It also suggests that policymakers must more deeply consider harvest patterns and species interactions when thinking about distributing and allocating quotas to vessels.Applied Mathematic
The Disappearing Index Effect
No full textThe abnormal return associated with a stock being added to the S&P 500 has fallen from an average of 7.4% in the 1990s to 0.3% over the past decade. This has occurred despite a significant increase in the share of stock market assets linked to the index. A similar pattern has occurred for index deletions, with large negative abnormal returns during the 1990s, but only 0.1% between 2010 and 2020. We investigate the drivers of this surprising phenomenon and discuss implications for market efficiency. Finally, we document a similar decline in the index effect among other families of indices.Author's Origina
Effects of Pd ensemble size in dilute and single atom alloy PdAu catalysts for one-pot selective hydrogenation and reductive amination
No full textIn the one-pot reaction between nitroarenes, aldehydes, and hydrogen, the desired outcome is the selective hydrogenation of nitroarenes to form aminoarenes that condense with aldehydes to form pharmaceutically relevant imines and N-alkylamines. One approach to facilitate the selective hydrogenation of nitroarenes over aldehydes involves using bimetallic catalysts with near equimolar ratios. However, structural characterization of metallic ensembles on the nanoparticle surface is challenging at such high alloying ratios, which hinders the elucidation of clear structure–property relationships. Here, we prepared a well-controlled series of dilute Pd-in-Au alloy catalysts with a fixed nanoparticle size as a model system to investigate the effects of surface Pd ensemble size, from single atoms to dimers and trimers, in the one-pot hydrogenation reaction between nitrobenzene and benzaldehyde as our probe reaction. The highest (near unity) selectivity to condensation products was achieved using the catalyst with the lowest Pd content prepared (Pd2Au98/SiO2), which predominantly exposed surface Pd single atoms as verified by surface-sensitive spectroscopy. Theoretical calculations reveal that Pd single atoms were inactive for benzaldehyde adsorption and thus enabled selective nitrobenzene hydrogenation. On the contrary, the adsorption of benzaldehyde became stronger than nitrobenzene for Pd trimers and larger ensembles, explaining the enhanced competitive adsorption from benzaldehyde with increasing Pd content. Our results demonstrate that the commonly used (near equimolar) alloying ratio is rather arbitrary and may not necessarily produce the highest selectivity to condensation products. Instead, we illustrate how nanoscale Pd ensemble size control tunes competitive kinetics to steer selectivity towards forming the desired condensation products.Chemistry and Chemical BiologyMaterials Science and Mechanical EngineeringAccepted Manuscrip
Belarusian Publishing in Europe: Post-2020 Trends and Implications for Library Collections
Get PDFThis paper focuses on the explosion of Belarusian-language publishing in Europe after 2020 and its implications for Western library collection development decisions. This study evaluates publishing output in Belarusian as reflected in 2020-2024 bibliographic data from Poland, Germany, Lithuania, the Czech Republic and Great Britain.Slavic Languages and LiteraturesAccepted Manuscrip
The Body and the Blood: A Theological Reinterpretation of the Hemorrhaging Woman
No full textTraditional theological understandings of the healing of the Hemorrhaging Woman (Haemorrhoissa) found in Mark 5:21–43, Matthew 9:18–26, and Luke 8:40–56 have overlooked key parts of her identity, reducing her to a mere symbol or theological device. Using disability studies and theology informed by the author's own battles with chronic pain, this analysis reclaims the woman's identity as it is presented in the original Markan text. By examining her as an impure, poor, lonely, and unnamed woman who was healed by Jesus through her own faith, this piece argues that the woman's marginality positioned her to have a unique and meaningful relationship with God. The research asserts that the story of the Hemorrhaging Woman offers an example of faith and resilience, and demonstrates that vulnerability can bring one closer to the divine.Author's Origina