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Design and Modeling of a Hybrid-Electric Drone System for Conversion
Get PDFWith the increased use of unmanned aerial vehicles (UAVs), the need for long range high capacity (\u3e1kg) drones has also increased. While these drones do exist, they use complicated and complex technology that proportionately increases the price and barrier to entry for these drones. The goal of this paper is to look at different designs for hybrid electric drones, model the series-hybrid design, and create a low-cost alternative drone that uses off the shelf components. A primary purpose for this document is to present the information required to recreate a simila
Genealogical Relationship Extraction from Unstructured Text Using Fine-Tuned Transformer Models
Get PDFThe paper tackles the task of extracting genealogical relationships, such as “sibling-of”, “parent-of”, “child-of”, and “spouse-of”, from unstructured, free-form text. In order to solve the problem, we propose a three-stage pipeline consisting of Named Entity Recognition (NER), Coreference Resolution (CR), and Relationship Classification (RC). NER identifies tokens in the text that refer to people, such as proper nouns or nicknames, using the SpaCy software. CR maps multiple tokens representing pronouns to their antecedents. For example, CR could map “She”, “His sister”, and “Maria” to the antecedent “Maria Johnson”. CR allows us to transform a genealogical relationship between two tokens, such as the sibling relationship between “him” and “his sister”, to a relationship between the corre- sponding antecedents, for example, “Bob Johnson” and “Maria Johnson”. Our novel algorithm for coreference resolution is based on the AllenNLP software. The last step is the RC, which classifies the relationship between two sets of tokens given adjacent context. We use the LUKE transformer deep-learning model to extract the genealogical relationships. The end-to-end pipeline can extract and correctly classify genealogical relationships from our hand- labeled testing set of Wikipedia documents with macro precision, recall, and F1 scores of 0.794, 0.616, and 0.676, respectively
Utopian Promises, Dystopic Realities: Teaching bell hooks “No Love in The Wild”
Get PDFThis original teaching activity discusses bell hooks’ film review of Beasts of The Southern Wild and explains how it can be used to encourage students to recognize how popular culture reproduces and reinforces disturbing paradigms. This original teaching activity, based on hooks’ review “No Love in The Wild,” encourages students to be informed while navigating visual images in popular culture. This activity also explains how hooks’ film review and the film can be used to empower students with strategies to analyze film and other visual images that are seemingly progressive but support the strictures and structures that reinforce patriarchy, racism, and classism within American culture
Fire Effects on Soil Organic Matter in the Creek Fire
Get PDFWildfires have increased in frequency and severity over the past few decades due to the increased concertation of CO2 emissions from anthropogenic influence. Soil carbon (C) sequestration has been identified as a climate change mitigation strategy; however, the influx of large-scale wildfires has accelerated landscape processes such as erosion, reducing soil aggradation, and soil C and nitrogen (N) protection. This trend is highlighted by the Creek Fire that occurred in September 2020 and burned 379,895 acres in the Sierra National Forest. This research is designed to close the knowledge gap regarding the impact of burn severity on soil organic matter (SOM) C and N distribution at the landscape scale in California. To accomplish this, 70 soil samples were collected two years following the Creek Fire at a depth of 0-5 cm. These SOM samples were separated into mineral-associated organic matter (MAOM) and particulate organic matter (POM) to better understand how these size fractions influence soil C and N stocks. Alone burn severity is not statistically significant; however, the multiple variable regression analysis shows that Landsat dNBR burn severity is a significant predictor variable for all MAOM-C, MAOM-N, POM-C, and POM-N when coupled with other predictor variables. Additional predictor variables with significance include lithology variables, vegetation variables such as moisture and total greenness, and topography variables such as elevation and roughness. The POM-N model was the best at depicting SOM relationships, by explaining 48% of the variance in POM-N; therefore, a predictive map was created to depict this relationship. The results of this study provide valuable information and context regarding post-fire SOM C and N storage and can be used to inform future management decisions involving landscape restoration
Facing Gender Absence: Questioning the International Relations Curriculum from a Peripheral Feminist Perspective and Practice
Get PDFThe International Relations field is historically tied to masculine, European, and white hegemonic ideologies. As a result, gender and feminist debates rarely appear on the construction of the International Relations university curriculum and its teaching practices. Considering this scenario, the main goal of this critical commentary is to present ways to face gender and feminist absence in the International Relations classroom. We demonstrate how inside-outside classroom interaction and debates can be a powerful tool to transform International Relations teaching and curriculum, opening space to feminist pedagogical perspectives and practices
Assessing Environmental Impact of the Built Environment by Adopting Life Cycle Design: Using Swanton Pacific Ranch as a Case Study
Get PDFTo combat the carbon emissions contributed to the atmosphere by the built environment, it is imperative that low-embodied-carbon materials choices be prioritized throughout the building design process. To achieve this, this professional project creates an Excel-based, open source, and user-friendly tool for the construction sector to make design decisions that prioritize the sustainability of structures, as one such tool does not currently exist. The use of OpenLCA software and the EcoInvent34 database are utilized to calculate the environmental impact of 25 different building materials, as well as energy and electricity consumption. Swanton Pacific Ranch (SPR) in Santa Cruz County is utilized as a case study site. This is accomplished through the comparison of two hypothetical structures to test the validity and user-friendliness of the excel-based tool, and make edits and improvements as needed based on feedback. From this process, the benefits of the tool, as well as areas for its continued improvement are discussed
Time-Domain Evaluation of Atmospheric Ducting Effects on X-Band Propagation Over Water
Get PDFThe marine atmospheric boundary layer (MABL) is the region of atmosphere that interacts with the ocean surface. The atmospheric variability (i.e. temperature and relative humidity) in this region can result in rapid changes in the refractive index with increasing height from the sea surface. The complex region can result in non-standard propagation of electromagnetic (EM) waves beyond the horizon under atmospheric ducting conditions. However, when ducting layers are not present, EM waves are limited to line-of-sight transmission. Atmospheric ducting research is typically conducted using radio frequencies in the X-band (around 8-12 GHz) due to its impact on performance of marine radars at those frequencies. Studies typically examine levels of received signal power or effects on radar returns in ducting conditions, but often ignore the time-domain effects of ducting which can also affect communications link performance. In collaboration with the Coastal Observing Research and Development Center at Scripps Institution of Oceanography (SIO), the ducting research in this thesis uses a channel sounder that consists of a X-band transmitter which transmits a coded pseudorandom sequence and a software-defined radio (SDR) receiver. Both transmitter and receiver are GPS synchronized so that the time-domain cross-correlation between the TX and RX signals can be found. In theory, if atmospheric ducting is present, there will be multipath propagation, and the TX-RX cross-correlation indicates multiple “peaks”, indicating multiple arrival times. Conversely, if little to no ducting is present, then the cross-correlation indicates a single “peak”. The channel sounding was evaluated over several over-water communications links, involving fixed-path and variable range sea tests with a moving vessel to verify if this hypothesis is true. The expected ducting conditions were determined by in-situ refractive index measurements of the atmosphere. Results from testing showed multiple peaks when strong ducting was expected, but an extensive sea test in strong ducting conditions is needed to distinguish multipath from ducting from that of terrain reflections. Further work is also needed to determine the computational model that accurately models multipath propagation through a duct, which is beyond the scope of this thesis
Upper Limb Tensegrity Exoskeleton
Get PDFTensegrity structures are composed of stiff rods and elastic cables suspended in a flexible tension network. Their inherent properties have several key advantages when used in assistive medical devices such as supportive braces or rehabilitation exoskeletons: 1) the lightweight and natural compliance reduces the power consumption required to operate the system; 2) the system stiffness and pretension can be individually tuned to accommodate the user’s needs; and 3) the impact-resistant properties can protect users in the event of collisions and falls. This project explores the design space of assistive tensegrity devices to augment human dexterity in the upper limb. Suitable tensegrity configurations were built through rapid prototyping and then characterized by their performance. The work contributes to a new data-driven framework for the long-term goals of the work: advancing the capability of automated tensegrity system design and contributing low-cost, custom tensegrity devices to the next generation of assistive medical devices