Long field-life systems are those for which operational, as opposed to capital, expenditures dominate the life time cost of the system. In established product categories, operational experience and historical maintenance data allows engineers to make informed decisions influencing maintenance during the early design stages when design changes are at their...
Modern engineered systems are increasingly integrated into society, decentralized, and interconnected. However, scale and complexity create unique challenges in system design, such as emergent behavior and unintended consequences. This work investigates the structural characteristics of robustness in complex engineered systems by identifying patterns of under-recognized vulnerabilities at various levels of...
The amount of energy we use and the ways that we get that energy sit on the edge of dramatic change as the carbon budget which can keep the planet under 1.5C of global average temperature increase gets smaller (Allen, 2018). In response, we continue to research and develop renewable...
Clashes of ideology are all around us, from our computer and television screens to our composition classrooms, and they merit attention within the composition classroom. This thesis examines the justifications and pedagogies that scholars in rhetoric and composition use to infuse issues of ideology and social ethics into writing instruction...
Free / Open Source Software developers come from a myriad of different backgrounds. While some contribute for personal reasons, many become involved because they receive compensation from corporations or foundations. The motivation for participating in a project can have dramatic impacts on how and what contribution an individual makes. These...
Old-growth dry-mixed conifer forests are valued as habitats for late seral forest species, for the
ecosystem services and landscape diversity they provide, and for their aesthetic appeal. The
structure of these forests has been heavily altered by historic logging of overstory ponderosa
pine and Douglas-fir. Additionally, changes in fire regime...
Design is a process of decision making. Organizations that are dedicated to systematic support of the design process tend to have higher profit margins. Further, studies of system development have shown that early-stage design mistakes have a large impact on incurred costs. Therefore, it is critical to identify methods to...
This thesis presents the contributions to substrate noise due to supply coupling and the effect of pin parasitics on the substrate noise generated by digital circuits. Various sources of substrate noise and their effect on analog circuits sharing the same substrate are discussed. A simulation approach to isolate the various...
Most accidents and malfunctions in complex engineered systems are attributed to human error. However, a closer inspection would reveal that such mishaps often emerge as a result of poor design and human- and component-related vulnerabilities acting together. To fully understand and mitigate potential risks, the effects of such interactions between...
This thesis examines factors limiting understory herb presence and flowering in young second-growth Douglas-fir (Pseudotsuga menziesii) forests on the west side of the Cascade Mountains, Oregon, USA. I studied the belowground effects of canopy trees on understory herbs and shrubs in old-growth forests using trenched plots from which tree roots...
This thesis complicates the traditional associations between authorship and alphabetic composition within the comics medium and examines how the contributions of line artists and writers differ and may alter an audience's perceptions of the medium. As a fundamentally multimodal and collaborative work, the popular superhero comic muddies authorial claims and...
Resilience is a key driver in the design of systems that must operate in an uncertain operating environment, and is a key metric to assess the capacity for systems to perform within the specified performance envelop despite disturbances to their operating environment. This paper describes a graph spectral approach to...
Contamination of recreational and shellfish waters with fecal pollution is a major water quality issue with associated economic impacts and human health risks. Reliable fecal source identification and rapid, quantitative analyses are essential components of risk assessment. Enteric bacteria that are endemic to specific hosts have a potential role as...
Civil engineers are aware of the impacts of structures on the global environment but the environmental impacts of a fire within these structures remains unknown. Fires present a unique hazard as it is difficult to predict the probability of the occurrence and the intensity. Traditional methods to identify the environmental...
Histone deacetylase (HDAC) inhibitors have the potential to de-repress epigenetically silenced genes in cancer cells, leading to cell cycle arrest and apoptosis. Dietary HDAC inhibitors derived from natural phytochemicals are promising anticancer agents. In this thesis, metabolites from natural organosulfur and organoselenium compounds, i.e. allyl mercaptan (AM), β-methylselenopyruvate (MSP) and...
Manufacturing technology has continuously evolved and advanced over the past century; this has led to an increase in the production of consumer and industrial goods driven by simultaneous growth in population and wealth. Despite the resulting economic and labor growth, environmental impacts of manufacturing have increased dramatically due to the...
Phylogeographic studies of six Pacific Northwest forest-associated
salamanders provide insight into historical and contemporary processes on
population genetic structure. Among Larch Mountain Salamanders (Plethodon
larselli), cytochrome b mitochondrial (mtDNA) sequences (381 bp) and random
amplified polymorphic DNA (RAPDs; 34 loci) supported separate Management
Units for northern and southern populations (12...
A bad software development process leads to wasted effort and inferior products. In order to improve a software process, it must be first understood. In this work I focus on understanding software processes.
The first process we seek to understand is Continuous Integration (CI). CI systems automate the compilation, building,...
The asymmetric nature of bit errors in several practical applications provides grounds for efficient error control techniques. The Z-channel model and special classes of codes like asymmetric error detection codes and t-asymmetric error correcting/d-asymmetric error detecting codes can be successfully used in ARQ protocols for feedback error control enhancement. This...
The main goal of automated test generation is to improve the reliability of a program by exposing faults to developers. To this end, testing should cover the largest possible portion of the program given a test budget (i.e., time and resources) as frequently as possible. Coverage of a program entity...
Professional software engineers have an arsenal of techniques such as unit testing and assertions to check their specifications, but these techniques require tools, motivation, experience and training that programmers without professional software engineering training may not have. As a result, professionals in other fields, such as scientific modelers, face greater...
This dissertation describes arthropod responses to and effects on decay processes in ponderosa pine, a dominant forest canopy tree in northern California. We used both descriptive and experimental field techniques to establish how arthropod assemblages depend on and are important to the disintegration of woody structures in forests of this...
Individual quota (IQ) management systems in commercial marine fisheries are highly diverse, differing in the security, durability and exclusivity of the harvesting privilege and the transferability of quota units. This diversity in the degree of harvest rights may influence the effectiveness of IQ fisheries to meet management objectives. We conducted...
Agriculture is now facing the ‘perfect storm’ of climate change, increasing costs of fertilizer and rising food demands from a larger and wealthier human population. These factors point to a global food deficit unless the efficiency and resilience of crop production is increased. The intensification of agriculture has focused on...
Four years of daily weather observations from Central Tunisia were available for testing the application of the Penman Equation to estimate reference evapotranspiration in the arid climate of Central Tunisia. The data included minimum and maximum temperature, minimum and maximum relative humidity, 24-hour wind run, and lysimeter measurements of reference...
Full Text:
use
these data with the Penman Equation including the Wright
and Jensen, FAO and Wright wind
The OSU Government Relations Office provides periodic updates that describe events in Washington, DC and Salem. These updates include insights on how budget and policy decisions at the state and federal level will affect OSU and are issued once or twice a month, depending on the level of activities in...
The OSU Government Relations Office provides periodic updates that describe events in Washington, DC and Salem. These updates include insights on how budget and policy decisions at the state and federal level will affect OSU and are issued once or twice a month, depending on the level of activities in...
The OSU Government Relations Office provides periodic updates that describe events in Washington, DC and Salem. These updates include insights on how budget and policy decisions at the state and federal level will affect OSU and are issued once or twice a month, depending on the level of activities in...
Mineral dust particles have been shown to act as cloud condensation nuclei, and they are known to interact
with developing tropical storms over the Atlantic downwind of the Sahara. Once present within liquid
droplets, they have the potential to act as freezing ice nuclei and further affect the microphysics, dynamics,...
Nitrous oxide is an important greenhouse gas that has both natural and anthropogenic sources in the modern atmosphere (Ciais et al., 2013). This project expanded the knowledge of the history of atmospheric N2O in the geologic past by measuring N2O concentrations in air trapped in very old polar ice. A...
While exercise can be prescribed for improving cardiovascular and muscle health, no prescription exists for increasing bone mass. Because bone deformation rate has been identified as an important variable related to osteogenesis, estimates of skeletal loading during human activities likely characterize the associated osteogenic stimulus. However, estimates of body segment...
The feeding ecology of a common temperate mesoherbivore, the oligophagous sea slug Placida dendritica (Gastropoda: Opisthobranchia: Ascoglossa), was examined from April 1985 to June 1989. Along the central coast of Oregon, Placida consumed three host species: the low intertidal green algae Codium setchellii, C. fragile, and Bryopsis corticulans. Individual slugs...
Aircraft-based in situ measurements of cirrus cloud ice water content (IWC) are
important for cloud microphysical/radiative modeling and satellite validation studies, yet
the measurements have proven challenging due, in part, to the large dynamic range of
IWC values present in cirrus clouds. To date, three instruments designed for the
measurement...
Five genetically and morphologically different winter wheat
cultivars, Hyslop (H), Yamhill (Y), Paha (P), Luke (L), and Sprague
(5) were blended in all possible combinations. These composites
plus the five pure stands were planted in the fall of 1973 at three
environmentally diverse locations in Oregon: Hyslop Agronomy Farm,
Corvallis;...
Soil respiration is a major pathway for carbon cycling in terrestrial ecosystems yet little is known about its response to natural and
anthropogenic disturbances. This study examined soil respiration response to prescribed burning and thinning treatments in an old-growth, mixedconifer
forest on the western slope of the Sierra Nevada Mountains....
Soil respiration is a major pathway for carbon cycling in terrestrial ecosystems yet little is known about its response to natural and
anthropogenic disturbances. This study examined soil respiration response to prescribed burning and thinning treatments in an old-growth, mixedconifer
forest on the western slope of the Sierra Nevada Mountains....
Soil respiration is a major pathway for carbon cycling in terrestrial ecosystems yet little is known about its response to natural and
anthropogenic disturbances. This study examined soil respiration response to prescribed burning and thinning treatments in an old-growth, mixed-conifer
forest on the western slope of the Sierra Nevada Mountains....
Organismal tolerance to abiotic environmental stresses contributes significantly to setting the distribution limits of organisms, as demonstrated by vertical zonation patterns in the marine intertidal zone. In this thesis, the ultimate (evolutionary) and proximate (mechanistic) causes of tolerance to temperature and emersion stresses associated with the intertidal zone were examined...
This thesis is the combination of two research publications working toward a unified strategy in which to represent complex engineered systems as complex networks. Current engineered system modeling techniques segment large complex models into multiple groups to be simulated independently. These methods restrict the evaluations of such complex systems as...