The Modular High Temperature Gas-Cooled Reactor (MHTGR) is a graphite moderated reactor that utilizes helium as its coolant. One consideration of importance is how the MHTGR will perform during a Depressurized Conduction Cooldown (DCC) accident, which generally can be divided into three phases: depressurization, air ingress, and natural circulation. After...
The research presented in this thesis is a continuation of collaboration between Oregon State University and Auburn University studying the feasibility of passively pumping liquid during boiling in a preferential direction using meso-scaled asymmetric surface patterns. Such a passive phase-change mechanism has great potential for thermal management in spacecraft and...
This study models the household demand for vehicle miles traveled with a focus on the effects from bicycle ridership and transit ridership. Through the use of data from the Oregon Household Activity Survey collected on behalf of the Oregon Department of Transportation, evidence is found that households participating in bicycle...
Forests are one of the largest repositories of terrestrial C. Understanding factors that drive organic matter transformations and nutrient efflux from these systems is therefore highly important. Temperate forests are of particular significance due to the large fraction of C that is stored below ground in the soil. Characterizing nutrient...
Practical bipedal robots need to be simultaneously efficient, robust, and versatile machines, but designing robots dynamically capable of these demands has been a significant bottleneck. We designed ATRIAS to be a highly dynamic biped capable of both walking and running untethered in real environments. To meet these goals, ATRIAS is...
We consider the problem of wireless spectrum management in cognitive wireless networks that maximizes the revenue for a spectrum operator. Specifically, we study the problem on how a wireless spectrum operator can optimally allocate its limited spectrum to various classes users/devices who pay differently for their spectrum per unit time....
The American beaver (Castor canadensis) was nearly extirpated by the late 1800's due to the fur trade. Due to reintroduction efforts, it now occupies much of its former range. Beavers are a keystone species and ecosystem engineers, greatly influencing riparian and instream habitats through selective harvesting of plant materials and...
As non-renewable resources dwindle and costs increase, it becomes ever more important for people to understand and control their electricity usage. Eco-feedback devices are being developed to increase user awareness and reduce consumption. In order for feedback devices to be successfully adopted into the home, however, they must be appealing...
Nitrification and denitrification are major biological processes transforming nitrogen (N) in soils to plant available N, highly leachable nitrate (NO₃⁻) and gaseous N oxides. Although many studies in the past have studied N cycling communities, the effect of increased N inputs on ammonia-oxidizer and denitrifier population dynamics is still under...
Alfaxalone (3a-hydroxy-5a-pregnane-11,20-dione) is a neuroactive steroid that can induce anesthesia. It has recently been reformulated and solubilized in 2-hydroxypropyl-β-cyclodextrin (HCPD). Propofol and the combination of ketamine and diazepam are commonly used induction drugs in all species. The objective of this prospective randomized and crossover design study was to evaluate the...
The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients...
Almost 600,000 people in the United States were treated for End Stage Renal Disease in 2010. A majority of those people received hemodialysis from central medical facilities. It has been reported a better treatment option for these patients would be realized if the patients had more frequent hemodialysis treatments. A...
The fate and transport of engineered nanoparticles (ENPs) such as titanium dioxide (TiO₂) are of concern due to their increasing use in consumer products. Although analytical methods for detection and quantification of ENPs in environmental matrices are being developed, these methods are difficult, time consuming, and not easily validated for...
Lodgepole pine (Pinus contorta) forests are widely distributed throughout western North America. However, the lodgepole pine forests of central Oregon are ecologically unique to the region, with a mixed severity fire regime, low cone serotiny, and their occasional presence as a climax species. Most of the research conducted regarding the...
Seeding is a vital tool to facilitate recovery of degraded ecosystems, but low seedling recruitment rates limit the utility of this practice in a range of ecosystems across the globe. Plant functional traits impact individual fitness through effects on growth, reproduction and survival. Consequently, seed and seedling trait variation among...
Commercial radish seed producers in the Willamette Valley of Oregon have observed a late season wilt in their seed fields. Twenty-two fields were surveyed for wilt in the Willamette Valley during June through August 2012 and 2013. Plants exhibiting wilt symptoms were collected from the fields and examined for vascular...
Wild turkeys (Meleagris gallopavo) were first successfully introduced into Oregon and Washington in the 1960s; the population has grown in size and expanded in distribution to a point where it provides an important recreational hunting opportunity in both states that generates significant funds for habitat conservation and contributes financially to...
To assist with risk-assessment with deepwater and ultra-deepwater prospects for offshore energy extraction as well as provide a useful tool for oil spill response, a spatially-explicit model was developed for comprehensive simulations of a blowout event from the wellhead to final fate and degradation. The Blowout and Spill Occurrence Model...
Endurance riding reflects a relatively new sport among equine athletic disciplines and is growing rapidly. Of all the equine athletic disciplines, endurance riding is the most closely interrelated with veterinary assessment and control to ensure that horses are not exercised beyond their athletic capacity. As endurance riding competition has evolved,...
This M.S thesis presents an interactive software tool that I have developed in the course of the past two years. This interactive tool is called AISO. AISO is aimed at interactive image segmentation and annotation tool designed to allow users to segment an image – such as those produced with...