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Big, Black C%#K: Desire, Race and Masculinity
Get PDFMy thesis examines perceptions of power in relation to white and black masculinity in the United States. The introduction invokes the work of Mireille Miller-Young, Hortense Spillers, Vincent Woodard and Hiram Pérez as a foundation to ground my discussion of agency, consumption, desire, homoeroticism and the characteristics of the Mandingo, which occur in both articles. In my first article, “Who’s Hungry: Consumption in James Baldwin’s ‘Going to Meet the Man'" I argue that "Going to Meet the Man" serves as a case study for exploring how black masculinity has the agency to consume its white counterpart. Drawing on Spillers' theory of pornotroping and Vincent Woodard's understanding of consumption, my article argues that Baldwin’s short story encourages readers to recognize that black men can and do have the ability to at once be othered and affective in a way that impacts everything white masculinity touches.
My second article, "Power and Pleasure: Mandingo Agency in Cuckolding and
Cuckolding Pornography" continues to interrogate black masculine agency by analyzing
cuckolding and amateur cuckolding pornography. I examine an amateur cuckolding video that was uploaded to a popular pornography website, which offers a narrative that illustrates the power dynamics between white and black men. Furthermore, I suggest that although hegemonic narratives lead us to read these sexual encounters as strengthening white masculinity, by inhabiting precisely what white masculinity desires and can never achieve, black masculinity is disrupting this hegemonic system. My hope is that the work that has been done in this project will serve as another framework that can be used to identify the ways in which white supremacy and sexual politics interact and systemically impact the U.S
Assessing Exposures and Simplifying Complex Mixtures of SVOCs for Hazard Characterization using Alternative Model Systems
Get PDFThroughout their lifetime individuals are exposed to complex mixtures of chemicals. The study of chemical mixtures is an internationally recognized research priority, but seemingly complex challenge. To reduce the intricacy of studying mixtures, researchers have identified different prioritization methods based on exposure or the toxicity of chemicals. However, understanding the prevalence and concentration of chemicals in the environment as well as their biological impacts is essential for assessing risk of a given chemical or chemical mixture. Throughout this dissertation, tools used for exposure science and toxicology were utilized to further understand chemical exposures and prioritize chemicals for hazard characterization.
In Chapter 2 fourteen chemicals identified in over 50% of personal samplers (G14) analyzed from a representative population, from fourteen different communities spanning three different continents, was utilized for toxicological investigations. This study describes a novel approach to prioritize and broadly evaluate the hazards of a representative mixture by coupling data from personal sampling devices with high-throughput bioactivity screenings using in vitro and non-mammalian in vivo models. To account for species and sensitivity differences, screening was conducted using primary normal human bronchial epithelial (NHBE) cells and early life-stage zebrafish. Chemical bioactivity was dependent on the model system, with five and eleven chemicals deemed bioactive in NHBE and zebrafish, respectively. Mixtures of the G14 and most potent G14 chemicals were created to assess potential mixture effects. In both NHBE and zebrafish, mixture effects were observed when screening mixtures of the most potent chemicals. Observations of BMC-based mixtures in NHBE (NHBE BMC Mix) and zebrafish (ZF BMC Mix) suggested antagonistic effects. In this study, consumer product-related chemicals were prioritized for bioactivity screening using personal exposure data. High-throughput high-content
screening was utilized to assess the chemical bioactivity and mixture effects of the most potent chemicals.
In Chapter 3 several approaches were explored to form sufficiently similar mixtures of polycyclic aromatic hydrocarbons (PAHs). There is a growing need to establish alternative approaches for mixture safety assessment of PAHs. Due to limitations with approaches, a promising alternative is to use sufficiently similar mixtures. However, there is a lack of an established framework to form sufficiently similar mixtures. Multiple data streams including environmental concentrations and empirically and QSAR derived toxicity data for cancer and non-cancer endpoints were used to prioritize components for mixture formations. Passive air samplers were deployed at a legacy creosote site impacted by wildfire smoke. A mixture of 30 parent and alkylated PAHS identified in samples was created (CF Mix). Mixtures of the CF mix were formed based on relative abundance (Abun Mix), average toxicity values (Tox Mix), and a weighted approach incorporating toxicity and abundance (Weighted-Tox Mix). Hazard characterization of these mixtures was performed using high-throughput screening in NHBE and zebrafish. Differences in chemical composition and potency were observed based on selected approach, with Tox Mix being the most potent mixture in both models. In NHBE Weighted- Tox Mix was the second most potent followed by Abun Mix and CF Mix. The Weighted-Tox Mix approach was determined to be the ideal approach due its ability to prioritize chemicals with high exposure and hazard potential. Results from this study will provide a workflow for prioritizing components to create sufficiently similar mixtures for hazard characterization. Toxicity information for less widely studied mixtures of PAHs was also identified and warrant further investigation into their specific mechanisms and chemical interactions.
In Chapter 4 paired indoor and outdoor passive samplers were deployed at twenty-four locations across the United States using a community engaged approach. Samples were analyzed for over 1500 SVOCs to identify common patterns in exposure profiles representative of indoor and outdoor air quality. Although less widely studied, indoor air pollutants can be anywhere from two to five times higher than outdoors. Impacts of household behavior and environmental and demographic factors on exposure profiles were also investigated. Unique differences between indoor and outdoor profiles were found, with indoor having higher concentrations and more detections of SVOCs than outdoor. A significant relationship between household use of air fresheners and candles/incense and an increase in detection and concentrations of fragrance chemicals was discovered. Associations between carpet use and SVOC detection frequency and concentrations was also observed. These associations were chemical dependent with some showing a positive association and others having a negative association with carpet use. Environmental and demographic factors also had an impact on indoor and outdoor profiles and were chemical dependent. Results from this study provide valuable information regarding indoor and outdoor chemical profiles and factors that impact the composition and concentrations of these chemicals. These findings can also help inform ways to reduce chemical exposure, by identifying certain consumer behaviors that may affect exposure profiles
Metabolic Implications of Red Raspberry Polyphenol Supplementation in High Fat-Fed C57BL/6J Mice
Get PDFObjective: Red raspberries are rich in polyphenols and fiber, relatively low in sugar compared with other fruits, and have been demonstrated to have favorable effects on energy homeostasis in mice. However, it has been unclear precisely which compounds within red raspberries possess the greatest bioactivity, and their mechanism of action. Two extracts were prepared from red raspberries, enriched in either hydrophilic or hydrophobic polyphenols. We tested the hypothesis that these two polyphenol extracts would differentially alter and improve physiological measures and the hepatic transcriptome of C57BL/6J male mice fed a high fat diet (HF), enriched with cholesterol and sucrose to emulate an obesogenic western diet.
Methods: Raspberry polyphenol extracts were obtained using FPX-66 resin and eluted with 25% and 80% ethanol solutions. Polyphenol extracts were partially oven dried, then freeze dried. Groups of mice were provided either a low fat diet (LF, 10%kcal fat, n=12), high fat diet (HF, 45% kcal fat, n=12), high fat died with added raspberry puree concentrate (RPC, n=8), high fat diet with added hydrophilic raspberry polyphenol extract (R25, n=8), or high fat diet with added hydrophobic raspberry polyphenol extract (R80, n=8) ad libitum for 10 weeks. Body weights, food intake, and glucose tolerance were measured. Post mortem, serum was collected for ELISAs, organ weights were recorded, and liver tissue was collected for triglyceride analysis and differential expression analysis (DEA). Messenger RNA was isolated from liver tissue and sequenced by Thermo Fischer Scientific.
Results: Energy efficiency, liver weights, and the adipose to body weight ratio in the R25 and R80 groups was intermediate to the LF and HF controls. Fasting blood glucose, serum triglycerides, and adipose tissue weights did not significantly differ between treatment groups. A trend toward significance was seen in a reduction of weight gain in the raspberry treatment groups. Differential expression analysis of the mouse groups revealed that the R25 diet acted agonistically towards the constitutive androstane receptor (CAR) and depressed the activities of several sterol regulatory binding proteins (SREBPs). The R80 diet acted agonistically toward the peroxisome proliferator-activated receptor alpha (PPARα).
Conclusions: Supplementation of a high fat diet with raspberry polyphenols extracts was able to improve liver function and energy efficiency in C57 mice. The hydrophilic raspberry polyphenol extract behaved as an agonist for the PPARα receptor, while the hydrophobic raspberry polyphenol extract behaved as an agonist for the CAR receptor. These findings suggest that select polyphenols found within red raspberries may serve as nutraceuticals that specifically target PPARα and CAR in liver
Use of Flashing Lights in Traffic Safety of Vulnerable Road Users
Get PDFVulnerable road users, anyone interacting with the roadway facility without the protection of an automobile, experience greater risk for more severe crash outcomes. Multimodal roadway facilities often times provide less separation and more points of conflict between different types of road users. To promote vulnerable road user safety, transportation agencies across the world provide a variety of additional roadway treatments. This dissertation studied the effects of three such safety treatments: flashing blue and amber-white lights on paving equipment and a 20-mph school zone flasher. The fundamental goal of these three traffic control devices is to provide an additional layer of safety leveraging the color, pattern, and presence of flashing lights. The extent of their effectiveness was evaluated based on queries raised by State and County transportation agencies. Evaluation of the traffic control devices provides planners and engineers a better understanding of their effectiveness and will facilitate more informed decision making on implementations to improve road users’ safety.
The effectiveness of flashing blue, amber, and amber-white lights installed on paving equipment for harmonizing speeds inside work zones during mobile nighttime operations was studied. Paving operation requires that the highest density of workers on the roadway will be located in close proximity to the paving equipment (paver). In a partial lane closure work zone, the condition considered in this study, there is rarely protective separation, e.g., a hard barrier, between workers and vehicles on high-speed Interstate roadways. This condition warrants effective traffic control devices to draw the attention of the drivers and promote compliance with temporary speed reduction. Using portable traffic sensors, 11-12 nights of data were collected. Flashing blue light installation on the paver showed a statistically significant 2.7 to 16 mph speed reduction. Speed reduction during the nights flashing lights were on ranged from 3 to 7 mph. The Oregon Department of Transportation in coordination with contractors and law enforcement established a provision to allow flashing blue lights on Pavers supported by the results of this study.
Flashing yellow and amber lights are popular and have been used since the 1950s on construction work-related vehicles. A study using a similar methodology as described in the previous paragraph did not find evidence of the effectiveness of installing flashing amber lights on the Paver in reducing speed. However, alternatingly flashing amber and white light was determined to significantly reduce speed (2.5 to 10.1 mph) from at-paver and downstream of paver locations. The margin of speed reduction showed a greater reduction (1.5 to 4.1 mph) during the flashing operation. Based on the outcome of this study, the use of alternatingly flashing amber-white lights on the paver to increase visibility and reduce speed near the vulnerable workers near the paver was recommended.
A School zone 20 mph flasher was studied for at-grade crosswalks in front of two schools in a driving simulator experiment. Forty-six participants successfully completed the experiment. Flashing sing operation correlated with greater speed reduction. When two children and one child and one adult were present at the crosswalk, speed reductions were greatest. The two children pedestrian level during the flashing operation received the largest amount of visual attention. Yielding rates were higher during the flashing operation. As a result, it was recommended that the flashing lights be used under low vehicle and pedestrian volumes.
The three experiments described in this dissertation have produced recommendations for traffic planners and engineers to make informed decisions that improve existing safety issues
Diversity and Activity of Microbial Extracellular Peptidases in Soil
Get PDFSoil nitrogen exists largely as organic matter, including plant liter, dead animal matter, and microbial necromass. About 90% of soil organic nitrogen is proteinaceous material that is too large for plants and microorganisms to assimilate directly. Protein depolymerization therefore plays a critical role in mobilizing this organic source of nitrogen, producing lower molecular weight molecules that are bioavailable for both microorganisms and plants. The decomposition of proteins in soils serves as the rate-limiting step of the nitrogen cycle. The ability of microorganisms to access and break down proteinaceous material depends largely on their production of extracellular peptidases, but it involves a trade-off with the energetic cost of producing and secreting these enzymes into the environment, including the risk that other microorganisms can compete with the peptidase-producing organisms for the products released through depolymerization. Consequently, in order to optimize this energy investment, there might be a tight connection between soil environmental conditions and microbial proteolytic activity. Despite its ecological importance, there is a lack of understanding about the diversity of these extracellular peptidases and their activity as an important factor influencing the protein degradability in soils.
In this dissertation, I first assessed the genetic potential for microorganisms to produce extracellular enzymes, and second, I developed and applied a novel approach to measure the activities of different classes of peptidases in soil. In my first two chapters, I evaluated the abundance and diversity of microbial extracellular peptidases, their evolutionary conservation, and distribution as a function of environmental habitat and lifestyle. Chapter 2 focuses on the secreted peptidases of prokaryotes (Archaea, Bacteria); chapter 3 focuses on Fungi, the dominant soil eukaryote. In both chapters, I analyzed secreted peptidases across microbial lineages using their genomic information and corresponding annotated protein sequences assembled from several databases, including MEROPS, Silva, JGI Genome Portal, and MycoCosm. Peptidase gene sequences of 147 archaeal, 2,191 bacterial and 612 fungal genomes were screened for secretion signals, resulting in 55,072 prokaryotic and 31,668 eukaryotic genes coding for secreted peptidases. I found that Archaea, Bacteria, and Fungi possess unique complements of secreted peptidases and there are differences in the number of secreted peptidases per genome, indicating potential differential abilities for organic nitrogen acquisition. The majority of secreted peptidase families not only follow the phylogenetic evolutionary distribution, but also segregate based on the microbial lifestyles and microbial habitats. This suggests that microorganisms optimize their secreted peptidases to match their surrounding environments.
In Chapter 4, I incorporated the use of selective inhibitors to block the activity of different classes of peptidases. I designed a protocol with these peptidase inhibitors to use directly in natural soils. I validated and optimized this protocol with pure enzymes and peptidase-supplemented soils. This research revealed that the profile of extracellular peptidase activities belonging to different catalytic types varies among soils and correlates with both soil chemical and microbial properties. This is in line with our assumption that soil microorganisms respond to their environmental conditions by investing in peptidases that can optimize their activity.
Collectively, this work provides a comprehensive and foundational understanding about the contribution of different catalytic types of microbial extracellular peptidases to organic nitrogen turnover in soils
Auxiliary Tasks for Efficient Learning of Point-Goal Navigation
Get PDFTop-performing approaches to embodied AI tasks like point-goal navigation often rely on training agents via reinforcement learning over tens of millions (or even billions) of experiential steps – learning neural agents that map directly from visual observations to actions. In this work, we question whether these extreme training durations are necessary or if they are simply due to the difficulty of learning visual representations purely from task reward. We examine the task of point-goal navigation in photorealistic environments and introduce three auxiliary tasks that encourage learned representations to capture key elements of the task – local scene geometry, transition dynamics of the environment, and progress towards the goal. Importantly, these can be evaluated independent of task performance and provide strong supervision for representation learning. Our auxiliary tasks are simple to implement and rely on supervision already present in simulators commonly used for point-goal navigation. Applying our auxiliary losses to agents from prior works, we observe a >4× improvement in sample efficiency – in 17 million steps, our augmented agents outperforms state-of-the-art agents trained for 72 million steps
Forests on the Move: Forest Inventories and Wood Anatomy from the Fragmented Forests of Guairá, Paraguarí, and Central, Paraguay
Get PDFForest composition in Paraguay has been in a state of change for the past half century due to land management practices, forest fragmentation, and deforestation for agriculture. How these factors affect dendrological diversity and wood anatomy in Paraguay is not well understood. This thesis documents Paraguayan forest composition on the macro and micro level through floristic composition inventories and comparative wood anatomy. Several biodiversity markers were observed in three federally protected areas (National Park Ybycuí, Natural Monuments Cerro Koi and Cerro Chorori), and compared to three small forests under private ownership in Eastern Paraguay (in the Guairá and Central Departments). Forty-three randomly selected transects were established for determining tree diversity and dbh. A total of 903 individuals were registered representing 35 families. Results show greater dendrological diversity and a marginally larger mean dbh in private lands than protected areas. In the second study, heartwood samples from Plinia peruviana (Poir.) Govaerts (Myrtaceae) and Plinia rivularis (Camb.) Rotman (Myrtaceae) were collected from a semi-deciduous humid forest in Aregua, Central, Paraguay, and analyzed via light microscopy. Comparison of vessel diameter, vessel length, and ray height between Paraguayan species of Plinia peruviana and Plinia rivularis and the reported Brazilian values were found to have significant differences. It is unclear what is responsible for these differences, although measurement technique, location of samples within the stem, and differences in climate may all have played a role. Understanding the changes in wood anatomy and forest structure between different eco regions in South America will aid in more reliable wood identification, as well as in understanding the effect of climate and human intervention on wood anatomy and floristic composition. The results of this thesis indicate a need for ongoing monitoring of both private and protected lands and wood anatomy as forests continue to adapt to human intervention.
Key words: Paraguay, tree diversity, floristic composition, protected areas, wood anatomy, Plinia peruviana, Plinia rivularisLa composición de los bosques en Paraguay ha estado cambiando durante el último medio siglo debido a las prácticas de manejo de la tierra, la fragmentación de los bosques y la deforestación para la agricultura insostenible. No es claro cómo estos factores afectan la diversidad dendrológica y la anatomía de la madera en Paraguay. Esta tesis documenta la composición del bosque paraguayo a nivel macro y micro a través de inventarios de composición florística y anatomía de la madera comparativa. Se observaron varios marcadores de biodiversidad en tres áreas protegidas a nivel federal (Parque Nacional Ybycui, Monumentos Naturales Cerro Koi y Cerro Chorori), y se compararon con tres pequeños bosques de propiedad privada en el este de Paraguay (en los departamentos de Guaira y Central). Se establecieron cuarenta y tres transectos seleccionados al azar para determinar la diversidad de árboles y el DAP. Se registro un total de 903 individuos que representan a 35 familias. Los resultados muestran una mayor diversidad dendrológica y un DAP marginalmente mayor en tierras privadas que en áreas protegidas. Estas diferencias se atribuyeron a diferentes factores ecológicos, así como a diferencia en el uso de la tierra. En el segundo estudio, se recolectaron muestras de duramen de Plinia peruviana (Poir.) Govaerts (Myrtaceae) y Plinia rivularis (Camb.) Rotman
(Myrtaceae) de un bosque húmedo semicaducifolio en Aregua, Central, Paraguay, y se analizaron mediante microscopia óptica. La comparación del diámetro del vaso, longitud y la altura de los radios entre las especies paraguayas de Plinia rivularis y Plinia peruviana y los valores brasileños reportados tienen diferencias significativas. No está claro cuál es la causa de estas diferencias, aunque es posible que la técnica de medición, la ubicación de las muestras dentro del tallo y las diferencias climáticas hayan influido. Comprender los cambios en la anatomía de la madera entre diferentes regiones ecológicas en América del Sur ayudara a una identificación de la madera más confiable, así como a comprender el efecto del clima y la intervención humana en la anatomía de la madera. Los resultados de esta tesis indican la necesidad de un monitoreo continuo de las tierras privadas y protegidas y la anatomía de la madera a medida que los bosques continúan adaptándose.
Palabras clave: Paraguay, diversidad arbórea, composición florística, áreas protegidas, anatomía de la madera, Plina peruviana, Plina rivularis
Coastal Soil and Structure Behavior during Earthquake-Tsunami Multi-Hazards
No full textCoastal multi-hazards, i.e., earthquakes followed by tsunamis, induce severe damage to coastal infrastructure. The multi-hazards can cause soil liquefaction, which is one of the major concerns for evaluating sediments transport potential and structure failure mechanisms. The objectives for this work is threefold. First, to build and validate a soil numerical model that is suitable for predicting soil liquefaction during multi-hazards. Second, to develop efficient numerical solutions for analysing soil model sensitivity with an uncertain and highly variable input parameter: soil hydraulic conductivity. Third, to couple the soil model with structure elements, in order to simulate the soil-structure-wave-interaction phenomenon with synthetic earthquake and tsunami wave motions created specifically for the Oregon coastline.
To meet the first objective, a single-column soil model is built using OpenSees finite element framework. The general soil liquefaction criterion, compatible for both residual liquefaction and momentary liquefaction, is applied, which allows the evaluation of soil's excess pore water pressure in vertical direction. The numerical model is successfully validated with one of the LEAP centrifuge tests for the earthquake motion as well as a large-scale laboratory wave test for the wave motion, separately. The three stages of a multi-hazards process is simulated, i.e., the earthquake stage, the quiescent stage, and the tsunami stage. An earthquake motion selected from the March 2011 Mw 9.0 Japan megathrust earthquake and several sinusoidal wave shapes of different wave periods are applied as the input for the soil model. Excess pore water pressure gradient time series are calculated along the soil depth. Notably, soil liquefaction potential is critical at the beginning of wave run-up and the end of wave draw-down. Numerical experiments also show the impacts from the length of the quiescent period, the wave period, as well as the general soil model input parameters.
To further meet the first objective, SCHISM is adopted for generating a more realistic tsunami wave shape as well as the corresponding quiescent period length for the Yaquina Bay. Two possible rupture scenarios for the Cascadia Subduction Zone are considered, one is a uniform regional slip case and another is a patchy slip case. Numerical experiments are conducted by using the single-column soil model with varying soil hydraulic conductivity and soil layer thickness. The parametric study shows that soil hydraulic conductivity has a strong impact to the prediction of excess pore water pressure and the liquefaction potential. Coastal sediments transport is evaluated by calculating the modified Shields parameter and the modified Sleath parameter, more specifically, reshaping the parameter determination by including the liquefaction criterion term. The analysis shows the potential of sediment movement positively relates to the degree of liquefaction, meanwhile, the magnitude and direction of the tsunami wave is still the main factor for determining the sediments' incipient movement behavior.
The first objective highlighted that soil hydraulic conductivity is the most sensitive and uncertain parameter in the u-p form of Biot's equation~--- a well known geotechnical engineering fact. To meet the second objective, a Stochastic Finite Element Method (SFEM) is derived for evaluating the impact from soil hydraulic conductivity variance to the prediction of excess pore water pressure as well as the pressure gradient. SFEM is compared with the traditional Monte Carlo method and the stochastic collocation method, which takes the lead in economizing the computation time while still keep acceptable accuracy. The impact from soil hydraulic conductivity varies between waves of different wavelength, and it also varies between the different time steps. A large-scale laboratory wave test is reproduced with the SFEM model, and the analysis shows the limitation of Biot's equation solver when dealing with wave motion that has a fast run-up and a negative draw-down elevation input.
SFEM estimates the impact from soil hydraulic conductivity variance, but it is not able to narrow down to the best case scenario of the input parameter as well as a spatial distribution. Thus, to further the second objective, a gradient-based inverse solution is adopted for optimizing the input parameters of the non-zero residual problem backwardly. The spatial variation is considered in multiple ways: spatial constant, direct spatial discretization, and continuous spatial discretization by using Karhunen-Loeve (K-L) expansion. Exponential and Gaussian kernels are reasonable statistical relationships for representing soil hydraulic conductivity spatial distribution with the K-L expansion. Including soil hydraulic conductivity spatial variation increases the capacity of the optimization, where continuous spatial discretization shows a sufficient decrease in the objective function, as well as continuous parameter distribution without a finer mesh being required. Thereafter, the determined soil hydraulic conductivity spatial distribution is able to be applied as a reliable parameter reference for engineering application.
Finally, to meet the third objective, the single-column soil model is coupled with a bridge section model that is supported by a pile foundation, to simulate the structure behavior during the multi-hazards. P-y materials with soil liquefaction effects are adopted for simulating the interaction response between soil and the pile. The numerical model is validated using a centrifuge test, during which, two earthquake motions are applied. Numerical experiments are conducted with 16 synthetic earthquake motions selected from ``random'' M9 earthquake simulations and the corresponding tsunami wave shapes generated by SCHISM along the Oregon coast. The earthquake intensity is negatively correlated to the wave intensity, meanwhile, the extent of structure reaction is positively correlated to the wave intensity. The locations of the absolute maximum bending moment change with wave properties, hydrodynamic forces calculated by wave velocity and wave elevation, as well as whether soil liquefaction to be considered. Also, soil hydraulic conductivity magnitude impacts are studied, which indicates the parameter is extremely sensitive for predicting pile reactions in a certain range of small values
Enhancing Detection of Marine Debris with Polarimetric Imagery
Get PDFMarine debris is a chronic and increasingly pervasive problem for coastal regions around the world. Debris poses environmental risks, threats to wildlife, and degradation of the natural environment. Recent research has shown the advantages of uncrewed aircraft systems (UAS) for detection and recognition of marine debris, including the ability to efficiently collect data over large stretches of coast. To date, most UAS imagery acquisition is performed with red-green-blue (“natural color”) imagery only. Polarimetric imaging, which captures information on the polarization state of electromagnetic radiation received at the camera, in addition to purely spectral information, has been shown beneficial in detection of human-made objects. This thesis investigates the ability to improve detection of marine debris using polarimetric imagery (PI). It is shown that PI bands increase the information content above and beyond spectral (RGB) bands and aid in visual detection and recognition of marine debris. Additionally, results of supervised classification revealed that classification accuracy improves through inclusion of image bands derived from the polarimetric information. While commercially available PI cameras are still very new and not quite operationally ready for installation on UAS, follow-on research using PI cameras on UAS is anticipated to greatly facilitate operational use of this new technology for marine debris mapping and management
Millimeter-Wave Wideband Low-Noise Amplifiers in 22FFL Technology
Get PDFThe deployment of advanced technology standards for 5G and beyond in cellular networks has resulted in interest in integrated circuits (ICs) operating at frequencies above 10GHz. This has sparked research on wideband circuits in commercial low-cost silicon technologies, operating at high RF and mm-wave frequencies. Given the wide range of operating frequencies (28GHz, 30GHz and 47GHz), such circuits must satisfy performance parameters across wide operating range. This thesis focuses on the implementation of wideband low-noise amplifiers (LNA) and addresses design challenges associated with mm-wave wideband impedance matching networks in state-of-the-art CMOS technologies