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Command, Control and Telemetry for Utah State University's Scintillation Prediction Observation Research Task (SPORT) MissionHaws, Jordan 01 May 2020 (has links)
The Scintillation Prediction Observation Research Task (SPORT) is a joint United States of America (USA) and Brazil small satellite mission to address the further under-standing of the preconditions leading to equatorial plasma bubbles. Utah State University (USU) is supplying four instruments towards this SPORT mission. These four instruments will allow measurements of the electric field and plasma density in the ionosphere which will help understand what gives rise to plasma bubbles in the ionosphere.
This thesis will discuss the command, control, and telemetry communications needed to operate the SPORT USU instruments. It will cover an overview of the instruments involved, how the instruments are controlled specifically, what commands were needed to run the instruments, what telemetry data was produced and how it was transmitted to the ground station, and how the data is made useful. The design process, challenges, and solutions to this system and project will also be discussed.
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Autonomous Trajectory Planning for Satellite RPO and Safety of Flight Using Convex OptimizationOrtolano, Nicholas G. 01 December 2018 (has links)
Optimal trajectory planning methods that implement convex optimization techniques are applied to the area of satellite rendezvous and proximity operations. This involves the development of linearized relative orbital motion dynamics and constraints for two satellites, where one maintains a near-circular reference orbit. The result is formulated as a convex optimization problem, where the objective is to minimize the amount of fuel required to transfer from a given initial condition to the desired final conditions. A traditional rendezvous and proximity operations scenario is analyzed, which includes examples of initial approach, inspection, final approach, and docking trajectories. This scenario may include trajectory constraints such as maximum allowable control acceleration levels, approach corridors, and spherical keep-out zones. A second scenario that ensures passive safety, in the event of control failures on the maneuvering satellite. The convex optimization problem is ultimately formulated as a second-order cone program. Algorithm CPU and memory requirements are analyzed. Several examples of resulting optimal trajectories are presented for both scenarios, and these trajectories are implemented in a nonlinear simulation.
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Evaluation of the Effectiveness of Flexible Debris Flow Barriers for Control of Huaycos Using Satellite Images and GIS, in the Basin of Rímac River, PerúPareja Dominguez, Marco Antonio, Pascual Figueroa, Henry Douglas, Silva Dávila, Marisa Rosana 01 January 2022 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Recurrent economic and human losses occur in populated areas caused by the debris flow, known in Peru as “huayco” and for which there is little information. To determine the effectiveness of debris flow barriers installed in 2016 in three high-risk creeks with slopes ranging from 29 to 35%, it was analyzed satellite images with the Geographical Information System (GIS). For that, it is necessary to obtain the volumes of both soil erosion in the upper basin transported by the debris flow and the retained solids by the barriers. Topographic, geological, geomorphological, and hydrological characteristics were evaluated, as well as the evolution of the population in the dejection cone. It was no possible to obtain results for all the destructive events because there are no cartographies, and the available satellite images do not have enough temporal or spatial resolution or present cloudiness greater than 20%. The field investigations after the ENSO 2017 occurrence made it possible to verify that the debris flow barriers allowed to avoid the loss of human life and material damage. The field measured volumes of the solids retained by the barriers and the previously estimated volumes of erosion were compared, and retention efficiency of 80–90% was obtained. It recommends continuing with this research because it is necessary to know debris flow characteristics for analyzing the convenience and technical requirements for the implementation of retention barriers in other dangerous streams that are difficult to access.
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Assisted GNSS Using the Doppler Frequency Track MeasurementPike, G. Elisabeth 05 June 2023 (has links)
No description available.
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The Evolution and Distribution of Precipitation during Tropical Cyclone Landfalls using the GPM IMERG ProductSauda, Samrin Sumaiya 07 June 2023 (has links)
Landfalling tropical cyclone (TC) induced precipitation poses a great risk to the rising coastal population globally. However, the impacts of tropical cyclone precipitation (TCP) are still difficult to predict due to rapid structural changes during landfall. This study applies a shape metric methodology to quantify the spatiotemporal evolution of TCP in the North Indian (NI), Western Pacific (WP), and North Atlantic (NA) basins. The International Best Track Archive for Climate Stewardship (IBTrACS) data and the Global Precipitation Mission (GPM)'s advanced Integrated Multisatellite Retrievals for GPM (IMERG) dataset is employed to study the 2014-2020 landfalling TCP at three analysis times: pre-landfall, landfall, and post-landfall. We examine three thresholds (2, 5, and 10 mm hr-1) and use six spatial metrics (area, closure, solidity, fragmentation, dispersion, and elongation) to quantify the shape of the precipitation pattern. To identify precipitation changes among the three analysis times and three basins, the Kruskal-Wallis test is applied. The three basins show important differences in size evolution. The greatest structural changes occur during post-landfall when the rainfall extent shrinks. The WP has the largest area of TCP and generates the highest maximum TCP of all basins. NA is the only basin where the precipitation area expands after landfall. NA also has the lowest closure for the three precipitation thresholds. NI precipitation has the lowest dispersion and maximum closure. Shape metrics such as closure and dispersion show a consistent inverse correlation. The maximum precipitation direction within the TCs is also examined in each basin. These results can inform guidelines that contribute to improved TCP forecasting and disaster mitigation strategies for vulnerable coastal populations globally. Future studies can apply shape metrics to the sub-basins in NI and WP to examine regional variability as there has been no such study in these basins. Future work can also investigate if the location of heavy rainfall within the TC structure affects flooding or other water hazards. / Master of Science / Landfalling tropical cyclones (TC) pose a significant threat to coastal populations worldwide, primarily due to the heavy rainfall. Predicting the rainfall during landfall is challenging as they undergo rapid changes. This study uses shape metrics to measure how this rainfall changes over time and space in three ocean basins: North Indian (NI), Western Pacific (WP), and North Atlantic (NA). The study uses a comprehensive collection of global TC best-track data i.e., International Best Track Archive for Climate Stewardship (IBTrACS). The rainfall measurement is derived from the satellite data i.e., the Global Precipitation Mission (GPM)'s advanced Integrated Multisatellite Retrievals for GPM (IMERG) to study landfalling rainfall between 2014 to 2020. Six spatial metrics (area, closure, solidity, fragmentation, dispersion, and elongation) were applied to quantify the shape and size of the precipitation pattern at three landfall times: pre-landfall, landfall, and post-landfall. The values of the shape metrics are compared between the ocean basins and landfall times using a statistical test. The results show that the most significant changes occur after landfall when the rainfall area decreases. WP has the largest area of rainfall and generates the highest maximum rainfall of all basins. NA is the only basin where the rainfall area expands after landfall. Shape metrics such as closure and dispersion share a consistent negative relationship. The maximum precipitation direction within the TCs is also examined in each basin. These results can contribute to improved tropical cyclone rainfall forecasting and disaster mitigation strategies for vulnerable coastal populations globally. Future studies can apply shape metrics to the sub-basins in NI and WP to examine regional variability as there has been no such study in these basins.
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Monitoring Agricultural Water Use Using High-Resolution Remote Sensing TechnologiesAragon Solorio, Bruno Jose Luis 02 1900 (has links)
Over the coming decades, both food consumption and agricultural water use are expected to increase in response to growing populations. In light of these concerns, there has been a growing awareness and appreciation of the objectives of agricultural sustainability, which has the broad aim of securing food and water resources, without adversely affecting the environment or disenfranchising future generations. To ensure that irrigated fields optimize their water use towards a more sustainable application while remaining compliant with any imposed restrictions on access to water supplies (i.e. through water licensing), it is necessary to understand and quantify the water consumption of crops at appropriate spatial and temporal scales. Evaporation (E), also commonly referred to as evapotranspiration (ET), is the physical process of water vapor transport from the surface into the atmosphere. Evaporation can be estimated via interpretive modeling approaches that combine meteorological, radiative, vegetation, and other related properties to estimate land surface fluxes at any given time.
The research presented herein aims to investigate the evaporative response of agricultural croplands across a range of spatial and temporal scales, with a focus on high-resolution and field-scale estimation. In particular, we explore the utility of novel CubeSat imagery to produce the highest spatial
resolution (3 m) crop water use estimates ever retrieved from space. These high-resolution results are expanded through time by retrieving a daily evaporation product, offering an enhanced capacity to provide new insights into precision agriculture. The effects and implications of higher spatiotemporal resolutions are explored and contrasted against governmental satellite missions that operate at lower resolutions. An exploratory study on the use of unmanned aerial vehicles (UAVs) is also performed, specifically in the context of their capacity to mount miniaturized thermal sensors: with the accuracy and limitations of these sensors for deriving evaporation-type products examined. The overarching goal of this research is to advance the utility of space-based estimates of evaporation for precision agricultural applications, and to provide new high-spatial and temporal agricultural insights that can be directed towards improving water management and address food security concerns in a more sustainable manner.
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Optimization of muscle progenitor cell isolation techniques for production of cultivated meatSteele, Alexandra P January 2023 (has links)
Traditional meat production has major sustainability and ethical concerns. Cultivated meat helps to address these concerns by reducing the need for mass animal farming. Muscle progenitor cells (MPCs) harvested from skeletal muscle are a promising cell source for cultivated meat. While various protocols have been developed for MPC isolation, which protocol is best suited for the cultivated meat industry requires further investigation. Therefore, the purpose of this thesis was to optimize the MPC isolation technique to produce a pure myogenic cell population and provide the cultivated meat industry with standardized procedures for production. For these proof-of-concept experiments, skeletal muscles harvested from the hindlimb muscles of mice were used. Cells were isolated from the harvested muscle then subjected to one of three protocols for MPC enrichment: pre-plating, ice-cold treatment (ICT), or fluorescence activated cell sorting (FACS). The pre-plating and ICT protocols resulted in impure cell populations with few MPCs after one week in culture. Therefore, FACS using two cell-surface markers, NCAM and CD34, was employed as a more specific method for MPC sorting. CD34+NCAM1- cells grew quickly, however, unwanted cell types remained following FACS. In contrast, CD34+NCAM1+ cells had a consistent small, rounded shape and slow proliferation rate. These cells remained viable in culture for several months and had high Pax7 expression, indicating they were a pure population of myogenic cells. CD34+NCAM1+ cells maintained their capacity to differentiate after culturing for an extended period, demonstrating their potential use for cultivated meat production. The results of this study provide a better understanding of the differences between previously published MPC isolation techniques. Future studies will investigate the potential for CD34+NCAM1+ cells to be grown on a larger scale. These experiments provide insight into MPC populations that may exist in livestock species and will help to streamline the early stages of cultivated meat production. / Thesis / Master of Science (MSc) / Traditional meat production is associated with numerous challenges including animal welfare concerns, human health concerns, and harmful environmental consequences. The global population is predicted to reach 9.7 billion by 2050, emphasizing the importance of alternative food sources to meet the increased food demand. Cultivated meat is a promising new protein source, with the intended purpose of providing a sustainable food source with reduced ethical concerns compared to conventional meat. While there are several challenges to overcome throughout the production process, a major consideration in the early stages of cultivated meat production is cell sourcing. Muscle cells harvested from a tissue biopsy are one proposed starting cell source which has the potential to make up most of the tissue in cultivated meat products. This thesis aimed to improve upon previously published protocols used for muscle cell isolation and provide an optimized cell population for use in cultivated meat production. The cell sorting protocol described in this thesis provides a highly efficient technique for muscle cell purification and long-term growth. The resulting cell population has many characteristics that are pertinent to cultivated meat and may advance the early stages of production.
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A model for predicting indoor signal levels of satellite transmitted signalsAprea, Matthew 29 July 2009 (has links)
Several possible approaches to creating a model for predicting satellite signal levels inside buildings are examined. These models make use of resonant cavity modes and vector ray addition. The cavity mode approach yields inconclusive results because of a problem with uniqueness, there are too many potential modes and no obvious way to decide between them. The ray model uses vector representation. It tracks changes, and combines rays at the receiver. Signal levels are normalized to free space values. An algorithm for the construction of such a model is developed and results are obtained. A three ray model, incorporating LOS, floor, and ceiling reflected rays gives reasonable agreement with experimental data. The types of information needed are the room height, the receiver height, if the receiver is in the vicinity of a window, and the elevation angle of the satellite. This model shows that a user has to move only a small distance to find an area where fading is brought to acceptable levels. / Master of Science
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Angiotensin II regulation of skeletal muscle regeneration, growth and satellite cell functionJohnston, Adam 12 1900 (has links)
<p> Local renin-angiotensin systems (RASs) have been described in many mammalian tissues. However, the role of angiotensin II (Ang II) in skeletal muscle is poorly understood with initial reports suggesting it may function to regulate overload-induced hypertrophy. Therefore, the purpose of this thesis was to 1) investigate the potential that adult skeletal muscle and muscle stem cells possess a local RAS. 2) Describe its role in regulating skeletal muscle regeneration and growth following injury and 3) demonstrate its capacity to regulate muscle stem cell activity and myogenesis. We report that cultured primary and C2C12 myoblasts and myotubes possess a local Ang II signalling system evidenced by the differential expression of angiotensinogen, angiotensin converting enzyme (ACE), and both angiotensin type 1 and 2 (AT1, AT2) receptors. Interestingly, myoblasts demonstrated the capacity to produce Ang II in spite of lacking renin expression. Furthermore, angiotensin receptors demonstrated differential localization with AT1 associated with actin filaments in proliferating myoblasts, and localized to the nucleus in differentiated myotubes. We also report that a local angiotensin system is present in vivo and responsive to myotrauma as cardiotoxin injection (to induce muscle injury) resulted in the increased staining intensity of angiotensinogen and AT1 during myogenesis with a progressive downregulation throughout the regenerative timecourse. </p> <p> To investigate the effects of Ang II signalling blockade on muscle growth and regeneration we induced muscle injury in mice supplemented with captopril (ACE inhibitor) or mice devoid of the AT1 a receptor. Histological analysis
revealed that ACE inhibition resulted in a decreased muscle fibre growth,
increased proportion of small myofibres, an inability to accrete myonuclei and a robust hyperplasia of muscle fibres. Similarly, AT1 a receptor ablation resulted in decreased muscle fibre growth following injury suggesting that these effects are
receptor specific. </p> <p> To investigate the mechanisms underlying these effects we assessed the role of Ang II in regulating muscle satellite cell function. In vitro experiments revealed that Ang II had the ability to regulate the early response of satellite cells to muscle injury by acting as a potent transcriptional activator of quiescent myoblasts and directing their subsequent migration. Furthermore, these migratory effects were mediated through an Ang 11-induced increase in matrix metalloproteinase 2 (MMP2) content and reorganization of the actin cytoskeleton. Interestingly, Ang II may also participate in the fusion of myoblasts as captopril treatment suppressed the expression of markers of differentiation (myogenin) and maintained the expression of markers of proliferation (Pax7, Myf5). In agreement with this, IHC analysis revealed that ACE inhibition also induced a strong trend for a decrease in the proportion of myogenin positive cells following injury. Collectively, these results implicate the activation of local Ang II signalling system as a pleiotropic regulator of skeletal muscle growth. </p> / Thesis / Doctor of Philosophy (PhD)
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Vibration of an Inflatable, Self-Rigidizing Toroidal Satellite ComponentPazhooh, Mitra Danesh 12 1900 (has links)
<p> Inflatable structures have attracted much interest in space applications. The three main components of inflatable satellites are inflatable struts, an inflatable torus as the structural support component, and some sort of lens, aperture, or array housed inside the boundary of the torus. This project is devoted towards understanding the dynamic characteristics of an inflated torus with a focus on the self-rigidizing torus, SRT, developed by United Applied Technologies.</p> <p> The self-rigidizing torus is manufactured from flat sheets of Kapton® that are formed into curved films with the regular pattern of hexagonal domes. The inflated torus can support its structural shape even when there is no internal pressure.</p> <p> Modal testing is used to determine the dynamic properties of the structure for comparison with the numerical model. The feasibility of using a non-contact in-house fabricated electromagnetic excitation is investigated. The first four, in-plane and out-of-plane, damped natural frequencies and their corresponding damping ratios and modes shapes are extracted and compared with prior experimental studies. A preliminary finite element modal analysis is carried out for a torus made of flat film and the results are compared with prior studies. Kapton 300JP®'s frequency-dependent modulus of elasticity is determined.</p> <p> Owing to the large number of hexagonal domes in the self-rigidizing torus, a simplified sub-structuring technique is used. Each hexagonal dome is replaced with a statically equivalent flat hexagon with the same mass and stiffness as the hexagonal dome. Then the finite element modal analysis of the self-rigidizing torus is carried out for an equivalent torus made of flat film. The geometric nonlinearity and the effect of the follower load on the stiffness are included in this analysis. The methodology is verified through the correlation between the analytical and modal test results of the self-rigidizing torus.</p> / Thesis / Doctor of Philosophy (PhD)
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