4353 research outputs found
Sort by
Final Project Report for Bricks from Recyclables
Get PDFThe Bricks from Recyclables team is dedicated to designing and constructing an eco-friendly concrete brick that incorporates plastic to tackle the issue of plastic waste in the environment. The sponsor, Samadhi Yoga Retreat, plans to use this innovative product as a building material on-site to recycle and repurpose plastic, thereby eliminating the impracticality of transporting plastic waste to a recycling center in the remote location.
The team conducted tests on four essential subsystems: shredder, mixer, mold, and brick. The shredder tests involved evaluating the shredder\u27s capability and speed. The capability test demonstrated that the shredder could process both PET and HDPE plastic effectively into appropriate sizes, with HDPE producing slightly more of the targeted size. The speed test demonstrated that the shredder could process five bottles of both plastic types in under five minutes. These tests showed that the shredder adhered to the shredder functionality working criteria.
The mixer test evaluated whether the mixture could produce a visually uniform blend in less than five minutes. All mixtures created in the mixer successfully met the criteria. However, the team recommends using a larger mixer for producing full-size bricks.
The mold functionality test evaluated the effectiveness of the molds utilized to fabricate the coupons. The 3-D printed molds demonstrated excellent performance, with easy ejection of coupons and convenient cleaning and reusability. However, the melamine coupon mold proved less efficient due to being hand-manufactured and requiring the application of messy silicone for sealing. To accommodate the size limitations of the 3-D printers available to the team, the full-size mold comprises a combination of melamine and 3-D printed components. This test showed that the 3D printed mold adhered to the mold functionality working criteria.
The brick tests included a compression test to determine the optimum plastic-concrete formulation and a weather resistance test to assess the brick\u27s water resistance. The compression test showed that pure Quikrete achieved a compressive strength of over 1900 psi for water ratios ranging from 7-7.5%. The team selected 7.5% water as it retained plastic particles more effectively. PET outperformed HDPE in compression tests. However, none of the coupons with plastic ratios ranging from 1 to 15 percent plastic on a mass basis, or 1.54 to 23.11 percent on a volume basis, met the 1900 psi requirement mandated by ASTM C90 [1]. The team recommends longer curing times as a way to increase compressive strength.
The final phase of compression testing was anisotropic tests, which tested the bricks\u27 performance in a more consistent orientation with how full-size bricks will be loaded. The results indicated that an increase in plastic particle size resulted in an increase in compressive strength. The rough surfaces of the coupons, caused by molds designed for testing in the other orientation, led to some of the lower fatigue stresses. This test demonstrated that modifying the mold\u27s orientation could increase the compressive strength and potentially lead to a formulation that meets the 1900 psi requirement. The team recommends further research and testing on the anisotropic orientation.
The weather resistance test evaluated the water absorption capacity and the formation of salt deposits as the bricks/coupons dried. All specimens underwent both tests and successfully passed. To meet the requirements of the absorption test, the bricks/coupons needed to absorb less than 20% of their original weight. The full-size ASTM C90 bricks performed better, with a range of 6-7%, compared to the coupons, which had a range of 8.8-14.9%
Totality: Abstraction and Meaning in the Art of Barnett Newman
No full textTotality offers a deeply researched and thoughtful account of the art of Barnett Newman (1905–1970). While Newman’s paintings are widely regarded as among the most significant statements of abstract expressionism—and emblematic of modernism at midcentury—they pose distinct challenges to formal description and historical evaluation. With this book, Michael Schreyach guides readers toward a transformed understanding of Newman’s profound body of work.Through a sequence of close readings, Schreyach examines six key terms—symbol, surface, self-evidence, space, standpoint, and scale—that illuminate the meaning of Newman’s claims for the “metaphysical” content of his art. Totality progresses from the meticulous analysis of the technical structure and visual appearance of specific works to critical and archivally documented arguments about Newman’s intentions. The result is an altogether original interpretation of the artist’s enterprise, as surprising as it is nuanced.https://digitalcommons.trinity.edu/mono/1185/thumbnail.jp
Interviewing Peter Gow — Dundee, June 24, 2017
Get PDFThis interview presents an initial dialogue about Peter Gow’s trajectory as an anthropologist, trying to bring to light particularly the fieldwork experiences and events that it had not been possible to commenton and explore in the published material. Its aim is to understand more closely the particular ways in which Peter Gow had come to arrive at the insights and the analyses presented in his brilliant ethnographies with the Yine/Piro people of Amazonia
Autonomous Planetary Rover Final Project Report
Get PDFThis report documents the 2022-2023 Autonomous Planetary Rover Team’s work. The main focus and goal of our team was to improve the locomotion of the rover through mechanical improvements to the suspension and steering systems. The final expectation for the rover given by our sponsor, Dr. Kevin Nickels, was for the rover to complete an obstacle course where it drives over obstacles the height of the radius of its wheel, traverses uneven terrain, and completes turns with a 12-inch turn radius. The main inspirations for our design of the suspension and steering systems come from previous planetary rovers that have completed missions on Mars and the Moon, specifically Curiosity and Sojourner. We have done substantial research on the mechanics of the rocker-bogie suspension system and have chosen this as our method of robust suspension. We also researched different methods of steering and settled on an independent steering system. In terms of primary subsystems, we have focused on suspension and steering, though we will also discuss design choices related to the chassis material and electronic components.
This project has been evolving and changing for multiple iterations—four previous teams have worked on the rover, each team focusing on different aspects of improvement. Our team is focusing on improving the mechanical aspects of the rover while making use of previous teams’ additions to the project, but will not focus on any systems related to the autonomous navigation of the rover. This year, the design problem was to mechanically improve the rover so that it was capable of going around and over obstacles in a simple obstacle course. Requirements of the design also included the Rover’s ability to carry a 100-pound load (to simulate experimental equipment) and to traverse over obstacles as tall as 5.1 inches (the radius of the wheels). These design requirements fed into project-specific requirements from our sponsor, which included having a rocker-bogie suspension system and independent steering. Another requirement was the capability of the rover to pass through a standard door frame in Trinity University’s CSI Building. These requirements reflect constraints of real planetary rover design, and will force us to consider environmental factors on the design. In this document, we will discuss all conducted tests and to what extent these tests showed that our prototype fulfilled each requirement.
Though individual design components of the rover proved to be successful, the overall prototype was unable to complete the required obstacle course due to issues with stability. The clearance, dimensions, and obstacle construction requirements were successful based on testing, and are important for the next steps of the rover. Some tests showed partial achievement of requirements, which demonstrate that the rover has been improved this year and is on the right track. The team concludes that the suspension system design is a partial success, as similar to the steering system design, because it functioned as expected though not integrated perfectly. The rover was able to be controlled by a joystick, and was capable of making wide turns - showing success for the desired independent steering design. The rover’s ability to overcome obstacles was also deemed a partial success, as though it could statically handle being on top of an obstacle without tipping excessively, it was difficult for it to dynamically climb the obstacle. The team believes that each subsystem of the rover prototype shows promise, and look forward to seeing future iterations
Language, exogamy and ethnicity in the Upper Rio Negro region
Get PDFIn this article we explore how languages interact with exogamous social units (e.g., clans and phratries) and descent ideologies (such as having a common mythical ancestor and emergence from the same mythical place) to help organize the multilingual and interethnic societies from the Upper Rio Negro region (URN) in the Amazon. We show that the expected alignment of language boundary, exogamous group and descent group is actually quite unusual. Complex social structures involving the aggregation of clans into larger ethnic groups or marriage alliances with other clans have important variations in the alignment of language, exogamy, and descent ideology. Existing alignments follow, in fact, a parametric variation that shed light on different contexts of multilingualism and interethnic relations. Given that language is one among many possible ethnic markers, and that no single ethnic marker is either necessary or sufficient to demarcate exogamous groups at any level of the system, we uncover the function of languages in URN societies in ambivalent processes that creating sameness and otherness within and across social units defined by affinity or common descent. This fluid and dynamic use of languages is grounded in social structure and interethnic relations, while simultaneously serving as a means to reinforce and change social and cultural relations
Into an interference zone: childbirth and care among Mehinako people
Get PDFThis article addresses issues of care and corporeality during gestation, childbirth, the postpartum period, and childcare through a case study conducted with Mehinako people. Among this Amazonian people, care forms the person, having an elementary function in the daily construction of kinship relations through means of affection. A recent trend has caused expressive transformations in the way women experience corporeality and the making of a person: the displacement of birth from the home to hospitals, motivated by women’s fear, desire, and curiosity. In the city, Indigenous women transit through medical institutions, which I propose may be read as interference zones. There, they undergo interventions from a set of preestablished technocratic routines and have to engage in ontological and epistemological disputes. Furthermore, they find themselves using their creativity to perform their own hospital births, and to interfere in their relatives’ childbirth experiences through measures of care. I analyse here the multiple meanings attributed to care, alongside the problems and possible solutions women anticipate for hospital childbirth, while seeking to contribute to reflections on corporeality and kinship and discussions of gender in Indigenous Amazonia
Homonuclear Ultracold Elastic \u3cem\u3es\u3c/em\u3e-wave Collisions of Alkali-Metal Atoms via Multichannel Quantum Defect Theory
Get PDFMultichannel quantum-defect theory (MQDT) provides a powerful toolkit for describing and understanding collisions of cold alkali-metal atoms. Various MQDT approximations differ primarily in how they characterize the so-called short-ranged K matrix Ksr, which encapsulates the short-ranged physics into a handful of low-energy parameters that exhibit simple and smooth dependence on energy and field. Here, we compare three different methods for computing Ksr for homonuclear collisions of alkali-metal atoms, from lithium to cesium. The MQDT calculations are benchmarked against numerically converged coupled-channels calculations that use a log-derivative propagator out to the asymptotic region. We study how well these approximations reproduce positions of s-wave magnetic Feshbach resonances, comparing with experiment where possible, and identify the limitations of various approximations
Jonathan’s Rust Adventures and the Quest for the Numerically Stable Soft-Sphere Integrator
Get PDFIn this thesis I will implement a numerically stable soft-sphere collision model using Hooke’s Law as the restoring force. This model allows choosing a desired coefficient of restitution and maximum penetration depth in order to generate appropriate values for the spring constant and damping. Then I will explore the applicability of various languages to the field of kD-tree based N-body simulations, concluding that Rust is competitive in both the time and memory usage to C/C++, which are the languages traditionally used for high-performance applications. Additionally, I found that the usage of higher-level languages like Java come at significant time or memory usage costs, making them of little value in the field of large astrophysics simulations. Lastly, as soft-sphere simulations require much smaller time steps for integration compared to hard-spheres, I implemented and benchmarked a priority-queue based adaptive time step system to only take the small time steps when needed. The benchmarks showed a significant speedup compared soft-sphere simulations without this adaptive time step method at roughly 8x faster. In direct particle-particle testing, the adaptive time step showed that with as little as 15 steps during a collision, which the adaptive time step method allows me to set, stable collision handling can be achieved across a spectrum of impact speeds and particle size ratios
Spatial and Statistical Analysis of Groundwater Contaminants in Shallow and Deep Aquifers of the Central Valley of California
Get PDFThe sediment aquifer of California’s Central Valley is threatened by various contaminants including arsenic (As), iron (Fe), manganese (Mn), and uranium (U). In this region more than six million people and an agricultural industry worth over 20 billion dollars (Faunt et al., 2016) rely predominantly on groundwater, and contamination poses both health risks and financial burdens due to costly remediation. I seek to identify the physical and geochemical processes that mobilize contaminants observed at levels that far exceed both federal and state regulatory standards. Contaminants such as As and U naturally occur in sediment and can be mobilized by either anthropogenic contamination or geogenic changes in the aquifer’s geochemistry. I use data from the Groundwater Ambient Monitoring and Assessment (GAMA) program to create spatial, statistical, and geochemical models to elucidate the mobilization mechanisms of As and U. I also explored the stability of aquifer geochemistry as influenced by drought, over-pumping, and agriculture. This study provides evidence that As is strongly correlated with areas of subsidence caused by over-pumping, consistent with the findings of (Smith et al., 2018). As drought conditions in the region worsen, As mobilization will be exacerbated in the shallow aquifer with a lack of oxic recharge causing lower redox potential. U mobilization is more complex and involves a multi-step process. U appears to use NO3 - as the electron acceptor for oxidation, which oxidatively dissolves U from uraninite in the aquifer matrix. Furthermore, U appears to form aqueous calcium carbonate complexes which prevent its reabsorption onto the mineral surfaces, stabilizing it in groundwater
Successful Sports Philanthropy Communication Strategies: A Focus on Major League Soccer’s (MLS) Promotion of the Safe Places to Play Initiative
Get PDFOrganizations have recognized the value and importance of corporate social responsibility by dedicating their time and resources to help the surrounding community. However, primary research centers on the traditional business world and not on how corporate social responsibility has evolved in other highly influential institutions, such as professional sporting organizations. Previous research has also explored nonprofit communication, yet few have followed how various organizations communicate a specific and shared campaign. Therefore, this thesis explores what communication strategies different community relations departments and foundations of Major League Soccer teams utilize regarding the Safe Places to Play initiative. Semi-structured interviews were conducted with representatives of these organizations, and themes were derived from their responses. The results of this study will benefit academics and professionals by advancing scholarship and providing insight for professional growth