High early strength concrete (HESC) allows for faster construction with less impact on traffic, thus reducing the indirect costs associated with a project. There are multiple methods for achieving early strength, such as alternative cements like calcium sulfoaluminate (CSA) or chemically accelerated portland cements. The standard criteria for an HESC...
Reinforcement learning has emerged as a popular tool for solving control tasks, with multiple works focusing on the complex and dynamic task of locomotion. However, the naive application of reinforcement learning to this problem often produces maladaptive policies that exploit the model or reward function. This results in behavior that...
Robotic Bipedal locomotion holds the potential for efficient, robust traversal of difficult terrain. The difficulty lies in the dynamics of locomotion which complicate control and motion planning. Bipedal locomotion dynamics are dimensionally large problems, extremely nonlinear, and operate on the limits of actuator capabilities, which limit the performance of generic...
The accumulation of fuels in fire prone landscapes, and changing climatic conditions, have resulted in increasingly volatile fire behaviors. As a result, social and operational risk, management expenditures, and budgetary requirements for responsible agencies are increasing. The United States Forest Service (USFS) manages 193 million acres across the United States...
Consistent with its charge under Oregon House Bill 3543, the Oregon Climate Change Research Institute (OCCRI) conducts a biennial assessment of the state of climate change science, including biological, physical, and social science, as it relates to Oregon and the likely effects of climate change on Oregon. This fifth Oregon...
The past three years have underscored the importance of quality digital library resources and services. Oregon Digital (https://oregondigital.org), the shared digital collections repository for the University of Oregon and Oregon State University, launched a new platform in February 2023. This poster will showcase the development and migration work that the...
Coastal hypoxia, or low oxygen episodes pose a threat to marine resources in the Pacific Northwest. Previous research into nearshore oxygen dynamics have linked coastal upwelling to this seasonally occurring phenomenon, however the manifestation of hypoxic waters over coastal fishing grounds was not well understood. Through a partnership with Dungeness...
Marine sediment core OC1706B-02J ( 46° 15.4178 N, 125° 42.4543 W, at water depth 2263m), was collected on the lower continental slope near the base of the Willapa Canyon. It is a rapidly accumulating site (~30cm/kyr) located near the thrust front of the Cascadia Subduction Zone. The site is also...
I researched depictions of dragons in several works of modern literature to conceptualize what a dragon looks like and how they generally function in popular media. From there, I researched several key characteristics of dragons to see how they work with science’s current understanding. I looked into size and scaling,...
The commercial groundfish fishing industry and groundfish research have a long concurrent history of activity on the Oregon continental margin. Within the non-whiting groundfish fishery, the target species are primarily flatfishes, sablefish, lingcod, and rockfishes, though landings of each have fluctuated over time. Recent work shows that over the past...
Harmful algal blooms (HABs) are a problem for coastal communities, the fishing industry, and coastal organisms. Pseudo-nitzschia spp. is a regularly occurring diatom in Oregon’s coastal waters. At times, Pseudo-nitzschia spp. can facultatively produce domoic acid, a neurotoxin that can bioaccumulate in the food chain. While regular shore-based sampling provides...
Low-tech habitat restoration techniques, including Stage 0 treatments, are increasingly applied but often lack robust evaluation of their effects. In 2018, one kilometer of the South Fork McKenzie (SFMK) River, OR was modified to the Stage 0 condition for the benefit of ESA-listed Chinook by raising the incised channel to...
Copper and iron are essential micronutrients that are required by marine primary producers for a variety of metabolic processes. Over 99% of both copper and iron are bound within organic complexes in the marine environment, however the molecular identity of many of these complexes remains unknown. The speciation of these...
Most marine fishes experience high rates of mortality during their early life history stages with far reaching consequences for adult population dynamics. Within a few weeks of hatching, relatively small changes in larval growth and mortality rates can lead to orders of magnitude variability in year-class strength. Growth and survival...
As global atmospheric carbon emissions continue to rise, scientists and land managers are increasingly looking to natural ecosystems to sequester and store carbon to buffer the impacts of climate change. Despite their small geographic size, many coastal ecosystems such as salt marshes, seagrass meadows, and mangroves sequester large amounts of...
The increasing focus on internationalization in Taiwan’s language-in-education policy has expanded the use of cross-cultural co-teaching pairs consisting of a native English-speaking teacher and a local non-native English-speaking teacher. While the model holds great potential for combining unique strengths, navigating cross-cultural communication in these co-teaching collaborations can be complex. This...
The Altar Valley is an important working landscape that supports biodiversity and vulnerable species in Pima County, Arizona (Huckelberry 2000). This semi-desert grassland, alluvial valley and 713,807-acre watershed composed of 39 subbasins serves as an aquifer to a portion of southwestern Tucson. This region of Southern Arizona has been identified...
Intraseasonal oscillations in the atmosphere-ocean system can affect weather patterns and regional ecosystems. In turn, these oscillations can be affected by climate variability, resulting in additive and/or non-linear responses of regional ecosystems to climate forcing. In the Northern California Current, a strong correlation was identified between the location of the...
Severe wildfires are increasing in the western United States, impacting vegetation structure, and in turn, forest regeneration conditions. These wildfires are also raising a substantial amount of scientific and management concern regarding the resilience of forested ecosystems, or the ability of the ecosystem to return to a pre-fire condition. This...
Toxin production by cyanobacterial harmful algal blooms (cyanoHABs) in freshwater systems has lasting ecological and human impacts. Nutrients, light availability, hydrology, and microbial community composition impact the frequency and intensity of toxic cyanoHABs. Climate change will exacerbate toxic cyanoHABs, making real time and predictive monitoring a vital tool for managing...
Microplastics (<5mm) are a ubiquitous environmental pollutant that have the potential to cause significant harm in many fish species. Therefore, understanding the quantities at which they are being consumed by living organisms is crucial for characterizing risk. There are currently gaps in the microplastic literature regarding microplastic data from finfish...
Hop (Humulus lupulus L. var. lupulus) is a diploid, dioecious plant with an extensive history of cultivation and use in brewing, as a textile, and for its therapeutic properties. Hop is prized for its ability to produce a variety of aromatic and flavor compounds, as well as compounds with anti-microbial...
Long-term, large-scale studies of meta-ecosystems provide critical information about how global change influences communities. In my dissertation, I analyzed data from studies encompassing 18 years (2006 – 2023) and over 1,000 km of coastline to investigate drivers of rocky intertidal community structure and dynamics. Specifically, I explored the roles of...
In the months preceding the 2016 presidential election and during the Trump presidency, rhetoric, composition, and communications scholars expressed an urgent concern about the threat that Trump and his political affiliates posed to the status of truth in political life (McComiskey; Rice; Harsin; Cloud). However, the conversations surrounding the discipline’s...
Advances in mobile autonomous vehicles for oceanographic sensing provide new opportunities for passive acoustic monitoring of marine mammals. Acoustically equipped mobile autonomous platforms, including gliders, deep-water profiling floats, and drifting surface buoys can survey for a variety of marine mammal species over intermediate spatiotemporal scales. Additionally, such mobile platforms may...
Interest is expanding for the potential role of estuaries, particularly seagrass and salt marsh habitats, to sequester carbon, mitigate ocean acidification, and support abundant fisheries. The important functions of estuaries are part of a broader set of ecosystem services, or benefits to humans, which are regulated by ocean and watershed...
Climate change and other anthropogenic impacts are threatening the existence of millions of species around the globe. On western continental boundaries, the large-scale secondary process of upwelling, which brings low pH, deoxygenated, high nutrient seawater to the surface, is compounded by climate change, that together could drive some species to...
River ecosystems throughout the arid southwestern U.S. are imperiled. Water management infrastructure, climate change, unsustainable water use, and political conflict harm the region's aquatic and riparian ecosystems. This case study surveys one such desert river, an endemic fish species, and conservation efforts in southwestern Utah. The analysis focuses on the...