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Beyond the Visible: Jointly Attending to Spectral and Spatial Dimensions with HSI-Diffusion for the FINCH Spacecraft
Get PDFSatellite remote sensing missions have gained popularity over the past fifteen years due to their ability to cover large swaths of land at regular intervals, making them ideal for monitoring environmental trends. The FINCH mission, a 3U+ CubeSat equipped with a hyperspectral camera, aims to monitor crop residue cover in agricultural fields. Although hyperspectral imaging captures both spectral and spatial information, it is prone to various types of noise, including random noise, stripe noise, and dead pixels. Effective denoising of these images is crucial for downstream scientific tasks. Traditional methods, including hand-crafted techniques encoding strong priors, learned 2D image denoising methods applied across different hyperspectral bands, or diffusion generative models applied independently on bands, often struggle with varying noise strengths across spectral bands, leading to significant spectral distortion. This paper presents a novel approach to hyperspectral image denoising using latent diffusion models that integrate spatial and spectral information. We particularly do so by building a 3D diffusion model and presenting a 3-stage training approach on real and synthetically crafted datasets. The proposed method preserves image structure while reducing noise. Evaluations on both popular hyperspectral denoising datasets and synthetically crafted datasets for the FINCH mission demonstrate the effectiveness of this approach.
Our code can be found at github.com/utat-ss/FINCH-destripin
SOC Proseminar - New Grad Students (Library Module)
No full textThis library module contains a few pages to help you get to know what library resources you have access to and strategies for using them: Sociology research resources Accessing materials Demography and data resources Organizing materials And more!
Preview: https://lor.instructure.com/resources/5131c7c854e24b06afc9b2c6a209f417?sharedhttps://digitalcommons.usu.edu/elearning_all/1065/thumbnail.jp
Trade-Offs in Lighting for DIC Strain Measurements in Vibration-Based Fatigue Testing
Get PDFVibration based fatigue testing offers a fast and efficient method for determining the breaking point of a material. This method often uses a device, called a strain gage, to measure the deformation of a test sample at a single spot on the test sample. However, these strain gages often break before testing is complete. To overcome this premature break, a laser vibrometer is often used to measure the amount of movement or the speed of the test sample throughout the vibration test. The deformation measured by the strain gage is compared against the amount of movement or velocity of the test specimen as measured by the laser vibrometer to allow for future comparison after the strain gage breaks. As an alternative to strain gages, Digital Image Correlation (DIC) is a popular camera-based, non-contacting method that determines the movement and deformation across the entire test sample. In a vibration-based fatigue test, DIC is desirable because DIC can continue to monitor the deformation in the test sample even after a strain gage would have broken. However, one of the major challenges of DIC is maintaining sufficient lighting on a test sample throughout a vibration test. Large motions towards the cameras require small apertures for improved depth of field while fast moving test samples require short exposure times to reduce motion blur. In this work, the trade-offs between aperture, exposure time, gain (artificial brightness), and external lighting (ring lights and strobe lights) is examined to compare the different lighting sources and determine if artificially increasing the brightness of an image by using gain can successfully be used without negatively impacting the deformation measurement from DIC. This was accomplished by first creating a series of tests that vary the aperture, exposure time, and gain for two different light sources. Second, an analytical solution was applied to the DIC movement measurements to allow for calculation of the strain on the test sample. Third, the deformation was compared to the calculated deformation from the movement measured by the laser vibrometer to provide a common comparison point between the different lighting tests. The tests performed showed the strobe lights provided the most stable and accurate results, but the ring lights had the lowest amount of difference between measurements. Artificially brightening the image through gain typically had no impact on the calculated deformation or the variation between measurements, except in the case of extremely small apertures. In this case, artificial brightening proved to be beneficial to increase the accuracy and decrease the variation of the analytical solution
An Examination of Traumatic Brain Injury and Genes for Neurotrophins and Apolipoprotein E in Predicting Cognitive Function in Older Adults: The Cache County Study
Get PDFRecovery from a traumatic brain injury (TBI) is influenced by a wide array of factors including age at incidence, number, and severity as well as genetic factors, some of which exhibit sex-dependent effects. This study examines how TBI history influences rate of cognitive decline in older adults, exploring the characteristics of TBI (e.g., number, severity, and timing) as predictors and interactions of TBI history with genetic variants suspected to play a role in brain health and late-life cognitive functioning. These genes include the Apolipoprotein E (APOE) as well as brain derived neurotrophic factor (BDNF) and its receptors. This study analyzed extant data from the Cache County Study on Memory in Aging (CCSMA), a longitudinal, population-based study of over 5,000 adults, aged 65 years and older.
A history of two or more TBIs was associated with lower scores on verbal list learning. Unexpectantly, females with a history of severe TBI scored higher on a test of verbal recognition recall compared to males with no history of TBI. Furthermore, females with at least one APOE ε4 allele and two or more TBIs scored lower on global cognitive and verbal learning tasks compared to males lacking a history of TBI and the APOE ε4 allele. BDNF receptor TrkB (rs2289656) moderated the association of TBI severity on recognition tasks such that individuals with a history of severe TBI and at least one minor allele for receptor TrkB (rs2289656) scored lower than individuals lacking a history of TBI and the minor allele. Overall, this study suggests that the course of late-life cognitive decline is associated with history of TBI and the associations examining severity or number of TBI may depend on sex and genotype. Although gene modification is not a viable intervention, one may consider how to enhance BDNF activity to reduce the deleterious effects of TBI on late-life cognition. For example, physical activity and diet are lifestyle factors that promote BDNF activity and may offer a target for intervention. Future research is needed to examine this and other possible interventions to mitigate the effects of TBI on late-life cognitive decline
Testing Resilience of Microalgae Biofilms When Exposed to Hydrothermal Liquefaction Aqueous Phase
Get PDFThere are a multitude of experimental and processing techniques in the bioenergy field that produce sustainable and carbon negative to carbon neutral methods of converting renewable resources into biologically based hydrocarbons. One example of a process is hydrothermal liquefaction (HTL) which specializes in converting wet biomass into biocrude oil. One reason that these processes are not used outside experimental testing is due to the high cost of performing these processes. There is potential to move these processes to larger scale testing and eventually industrial adaptation if breakthroughs are made to offset the process expenses. There is a waste product produced in this process called the aqueous phase. The hydrothermal liquefaction aqueous phase (HTL-AQ) has no current use, is expensive to dispose of, and consists of high concentrations of nitrogen (N), phosphorus (P), environmental toxins such as phenolic compounds. If HTL-AQ were able to be used to produce value-added products, the value of those products could be used to offset the expenses of the process, thus increasing the likelihood of HTL being used to produce bioenergy in an economically sensible way. Recent research has shown that microalgae biofilms both uptake N and P while also being more resistant to toxins than planktonic or free-floating algae. Since HTL-AQ does contain high concentrations of N and P, this project explores methods to grow microalgae biofilm cultures in dilutions of HTL-AQ. The technology used to cultivate these biofilms is called the rotating algal biofilm reactor (RABR) based on recent studies conducted at Utah State University (USU). Results from this experiment indicate that a 1:3 dilution of HTL-AQ to deionized (DI) water is able to grow microalgae biofilms. This data suggests that there is merit to finding value-added uses to HTL-AQ in ways that can offset HTL expenses, and that further investigation is warranted
Chemical-Mediated Mate Attraction in Clover Root Curculio (\u3ci\u3eSitona hispidulus\u3c/i\u3e F.), A Belowground Pest of Forage Crops
Get PDFCurculionid beetles are well known for their production of semiochemicals, including contact (e.g. cuticular hydrocarbons) and volatile pheromones that mediate conspecific attraction and mating. Clover root curculio (CRC; Sitona hispidulus) in particular is an emergent, soil-borne pest of significant concern to producers of alfalfa and other leguminous crops in the United States. Producers have few control options for CRC and a greater understanding of chemical-mediated attraction in this species can potentially improve the sustainability of its management. To examine which chemical cues are important for affecting the behavior of CRC and whether there are sex-based differences in response, I performed behavioral assays using an olfactometer (i.e., Y-tube). This effort was complemented with solvent-based extractions of cuticular hydrocarbons and analysis via Gas Chromatograph Mass Spectrometer (GC-MS) to characterize contact chemicals that can also contribute to conspecific recognition and attraction. Olfactometer assays suggest that CRC most likely has a male-produced, volatile aggregation pheromone, as females exhibited a strong preference for male odors. In contrast, our cuticular hydrocarbon data suggest a lack of sex differences in their epicuticular wax layer. Knowledge of chemicals involved in mediation of Curculionidae mating interactions is essential for the development of ecologically sound strategies for the control of below-ground pests. Once semiochemicals are identified and behaviors observed, we can use this knowledge to develop a cost-effective detection method, such as semiochemical-baited traps. These traps could alert growers of the presence of CRC in their fields, disrupt mating, as well as draw some away from their crops
Connection and Isolation: A Musical Exploration of Emotion
Get PDFMusic is emotional and inherently connective, and this paper addresses how research in social work and emotion can be communicated and understood using a musical performance. Using the research of Dr. Brené Brown, I explored the concept of near and far enemies of emotion with a musical perspective and commissioned composers to write a piece of their interpretation. Near and far enemies are Buddhist terms typically attributed to the Four Immeasurables: loving-kindness, compassion, empathetic joy, and equanimity. The far enemy of an emotion is its opposite, and it typically produces a harsh outcome. Near enemies are not as obvious. Similar to far enemies, they produce a disconnecting effect, but the attack is more subtle. A near enemy can easily be confused for the base emotion. Dr. Brown applied this concept to all emotions that connect us, rather than solely being an exercise for the Four Immeasurables, and she uses the English language to explore and demystify these ideas. It is essential to understand ourselves and our emotions better to be able to communicate our needs with others more effectively. To expand upon her research musically, I hired three student composers to write original works after I assigned them an extensive worksheet that allowed them to explore what these ideas mean to them individually. I then premiered these pieces and explained the concepts to an audience. Participants were asked to fill out a worksheet during the performance, and their responses are the basis for my Honors Capstone
The Theoretical Simulation Analysis of Vibrations in Small Satellites: A Material Study
Get PDFAccounting for vibrations is a critical component in the design of a small satellite frame. This research aims to determine the most effective material for a small satellite. This will be accomplished through finite element analysis, simulated vibration fatigue testing, and material samples of the same physical design and proportion.
Four materials have been determined for testing, the first two of which are 6061 Aluminum and 4130 Stainless Steel, due to their ductility and industry prominence. 2024 Aluminum was selected due to its high ductility which is higher than that of 6061 Aluminum. Finally, while Cast Iron is not as applicable to the aerospace industry, it was selected to serve as a control for brittle materials.
Fatigue is the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. It is difficult to detect progressive deterioration during the fatigue process, so catastrophic failures can occur without warning. It is estimated that 85 percent of all structural failures are caused by material fatigue. The purpose of these findings is to display how random vibrations contribute to structural failure due to fatigue
Merritt Coil CubeSat Attitude Test System (MCCATS)
Get PDFTraditional CubeSat Attitude Determination Control Systems (ADCS) leverage the Earth\u27s magnetic field to point and detumble satellites using magnetorquers. Very few commercially available devices, however, generate adjustable uniform magnetic fields with a sufficiently large volume to test these ADCS in 12U satellites before launch. Furthermore, the existing devices are cost-prohibitive for smaller universities and organizations interested in developing small satellites. To assuage this challenge, we developed MCCATS: a modular, low-cost, and footprint-efficient test bed capable of generating a large volume of uniform and programmable magnetic field. The MCCATS design is based on the Merritt coil, which contains four large coils on each of the three axes. In comparison to the more ubiquitous Helmholtz coils, Merritt coils generate a larger ratio of usable volume to total cage volume. When simulated, our Merritt coil design took up less than one-third of the floor space of existing Helmholtz cages that produce a similar usable volume. Furthermore, instead of requiring 3 expensive programmable power supplies (1 per axis), we designed a system that utilizes one constant power supply and three self developed programmable coil drivers, providing a budget-friendly and flexible alternative for driving the Merritt cage. The resulting testbed was designed to be capable of generating magnetic fields up to 2.5 gauss that can be oriented in a single specified direction or configured for rotation
Printed Circuit Board Reaction Wheels for Small Satellites
Get PDFReaction wheels are critical for spacecraft attitude control, enabling precise pointing. However, conventional designs are bulky and expensive, limiting their application in CubeSats and PocketQubes. This paper introduces a novel PCB motor architecture specifically designed for reaction wheels in small satellites. Our design integrates motor windings as traces on the PCB and utilizes a dual-purpose rotor-flywheel combination, resulting in a volumetrically efficient configuration. Additionally, the reaction wheel’s PCB casing enables multifunctional capabilities, such as serving as the satellite’s structural elements or solar panels. The accessibility of PCB manufacturing offers a simplified and cost-effective production process, with each reaction wheel costing under $100, significantly reducing the cost compared to current commercial-off-the-shelf (COTS) options. Our prototype demonstrates a stall torque of 8 mNm, a maximum power consumption of 5W, and a maximum angular velocity of 170 rad/s, all within a mass of 140g and a thickness of 9mm, facilitating easy integration into a 1U CubeSat. Numerical simulations based on experimental data further validate the performance of our design