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NSFs I-Corps : aligning incentives & entrepreneurship in academia
Get PDFAbstract only.This panel discussion will be led by Rebecca Shearman, Program Manager, NSF Technology, Innovation and Partnership Directorate, Regional Innovation Engines program. The panel discussed how aligning P&T incentives could affect our universities and participation in the NSF I-Corps program, unleashing sustained innovation addressing significant societal challenges
Modeling human expertise for providing adaptive levels of robot shared autonomy
Get PDFIn shared autonomy, a robot and human user both have some level of control in order to achieve a shared goal. Choosing the balance of control given to the user and the robot can be a challenging problem since different users have different preferences and vary in skill levels when operating a robot. We propose using a novel formulation of Partially Observable Markov Decision Processes (POMDPs) to represent a model of the user's expertise in controlling the robot. The POMDP uses observations from the user's actions and from the environment to update the belief of the user's skill and chooses a level of control between the robot and the user. The level of control given between the user and the robot is encapsulated in macro-action controllers. The macro-action controllers encompass varying levels of robot autonomy and reduce the space of the POMDP, removing the need to plan over separate actions. As part of this research, we ran two users study, developed a method to automatically generate macro-action controller values, and applied our user expertise model to provide shared autonomy on a semi-autonomous underwater vehicle. In our first user study, we tested our user expertise model in a robot driving simulation. Users drove a simulated robot through an obstacle-filled map while the POMDP model chose appropriate macro-action controllers based on the belief state of the user's skill level. The results of the user study showed that our model can encapsulate user skill levels. The results also showed that using the controller with greater robot autonomy helped users of low skill avoid obstacles more than it helped users of high skill. We designed a controller value synthesis method to generate the variables that control the levels of autonomy in the macro-action controllers. We found differences in how the users drive the robot using a decision tree generated from the data recorded in the first user study, and we used these differences to program simulated user ``bots'' that mimic users of different skill levels. The ``bots'' were used to test a range of variables for the controllers, and the controller variables were found from minimizing obstacles hit, time to complete maps, and total distance driven from the simulated data.For our second user study, we looked at users' satisfaction without robot autonomy, with the highest amount of autonomy, and with the autonomy chosen by our expertise model. We found users we classified as beginners ranked the autonomy more favorably than those ranked as experts. We implemented our expertise model on a Seabotix vLBV300 underwater vehicle and ran a trial off the coast of Newport, Oregon. During our trials, we recorded a user driving the vehicle to predetermined waypoints. When beginner actions were performed, the user expertise model provided an increased level of autonomy which either increased throttle when far from waypoints or decreased throttle when close to waypoints. This demonstrated an implementation of our algorithm on existing robot hardware in the field.Keywords: Shared autonomy, Robotics, Human-robot interactio
Boiler Bay
No full textKeywords: Boiler Bay; Mytilus polymerus; Mitella californianus; Paranemertes peregrina; Balanus glandula; Thais emarginata; Balanus cariosus; Acmaea pelta; Acmaea digitalis; Penitella penita; Mopalia lignosa; Katharina tunicata; Tubulanus pellucidus; Sabella crass
A study of zonation on a moderately exposed sandy beach at Seal Rock, Oregon
No full textKeywords: Talitridae; Seal Rock; Zonation; Orchestoidea corniculata; Thoracopheli
Enchanted Elliott: The Interactive Forest Adventure
No full textCurrent methods for visualizing forest rely on geospatial and remote sensed data. Such data can be used to create visualization and to perform simulations. Currently, however, these visualizations are often limited to 2D or abstract representations. These methods can be effective for large scale data visualization and low accuracy needs. However, when high detail representations are needed they fall short. This research has developed a realistic 3D forest visualization prototype that takes detail to the next level, with absolute reproducibility in mind. The high-fidelity visualization includes real-world topography, with real-world tree information. To further enhance the visualization, animals, streams, sound, additional flora, and weather conditions have been added
Magma dynamics and evolution in continental arcs : insights from the Central Andes
No full textConstraining the magma evolution and dynamics that lead to the eruption of large volume continental arc systems is fundamental to our understanding of continental crust formation. An investigation into the magmagenesis that results in the formation of the Central Volcanic Zone (CVZ) in the Andes of South America, situated atop overthickened continental crust (800 km³ DRE) at 3.49 ± 0.01 Ma. The eruptive history of the Guacha II Caldera from pre-caldera to post-caldera is fully represented, allowing magma dynamics associated with a complete caldera cycle, from pre-climactic (catastrophic caldera-forming) magma accumulation through to post-climactic effusions that are part of the resurgent history of the caldera, to be examined. Analysis of the high-K, calcalkaline suite of andesite to high Si-rhyolite Tara pyroclastic deposits provides insights into the storage conditions and magma dynamics leading up to a supervolcanic eruption. The Tara eruptive products define a liquid line of descent from the basal andesite lava (62 wt % SiO₂) to the high-silica rhyolite post-collapse Chajnantor Dome lava (78 wt.% SiO₂), with major and trace element trends consistent with fractionation of quartz, plagioclase, orthopyroxene, hornblende, sanidine, biotite, and Fe-Ti oxides. Isotope ratios span a significant range in ⁸⁷Sr/⁸⁶Sr (0.709 to 0.713) and a relatively narrow range in ¹⁴³Nd/¹⁴⁴Nd (0.512179 to 0.512297) and δ¹⁸O[subscript (qtz)] (+8.68 to +8.43‰). These data require AFC processes to explain both the isotope and trace element compositions in the Tara magmas. Geothermobarometry reveals pre-eruptive temperatures (~800 - 950 °C), pressures (~200 MPa), and H₂O contents (~5 wt%) that suggest storage of a large-volume rhyodacite magma reservoir between 5 and 9 km depth in the upper crust. Analyses of quartz-hosted melt inclusions from pumices in the climactic plinian and ignimbrite phase of eruption reveal that pre-eruptive H₂O contents in the plinian pumice overlap with those in the ignimbrite pumice (2.2 to 6.0 and 2.1 to 5.4 wt.% H₂O, respectively). The ignimbrite magma, however, contains higher CO₂ (800 km³ Tara ignimbrite. Extrusion of three post-caldera domes followed caldera collapse. Subtle differences between these domes invoke separate coexisting "pods" of magma that evolved independently from one another from the remnant magma that is represented by the ignimbrite. Analyses of quartz-hosted melt inclusions from the post-collapse Chajnantor Dome suggest that the highly-differentiated remnant magma contained no detectable CO₂ and low H₂O contents, representative of a degassed magma. The eruptive transition during the climactic eruption was not controlled by the volatile budget of the melt but more likely by external factors such as vent geometry and conduit evolution. Post climactic effusive volcanism reflects the degassed nature of the remnant magma. Using a suite of volcanic rocks from the CVZ, we quantify the effect of assimilation of continental crust on magmatic oxygen fugacity (ƒO₂). We use several proxies to estimate the ƒO₂ recorded by lavas, pumice and scoria: 1) whole rock Fe³⁺/ΣFe ratios, 2) Fe³⁺/ΣFe ratios in quartz-hosted melt inclusions, and 3) Fe-Ti oxide oxybarometry. Samples span a range of crustal contribution, as indicated by their radiogenic isotope compositions (⁸⁷Sr/⁸⁶Sr = 0.705-0.713), and cover the full suite of magma compositions erupted during the Neogene history of the arc (52 - 74 wt.% SiO₂). Some samples show excellent agreement across multiple ƒO₂ proxies. In other cases, where pumices show evidence of alteration in hand-sample for example, the ƒO₂ recorded by bulk Fe³⁺/ΣFe ratios is two orders of magnitude more oxidized than corresponding ratios from melt inclusions or Fe-Ti oxides. This suggests modification of whole rock Fe³⁺/ΣFe ratios, but not melt inclusion Fe³⁺/ΣFe ratios, by syn- or post-eruptive processes and that care must be taken when relying on bulk techniques to determine magmatic ƒO₂. We cannot resolve any oxidation due to crystal fractionation in our sample suite. Crustal assimilation, however, can oxidize arc magmas. The increase in ƒO₂ due to crustal assimilation reaches, but does not exceed, ~1 log unit - even in the Andes, where crustal assimilation is extreme.Keywords: Magma evolution, Central Andes, Oxygen Fugacity, Magma dynamic
Design and Analysis of an Optical Wireless Receiver for a Hybrid WiFi Free-Space Optical (WiFO) Communication Network
Get PDFThe increasing demand for higher data-rates in spectrum-deficient indoor WiFi networks calls for the adaptation of hybrid systems, consisting of RF and optical wireless channels. The novel hybrid WiFi Free-Space Optical (WIFO) system was introduced to enhance the wireless capacity of indoor WiFi networks. In this thesis, an optical wireless channel was designed and implemented as part of the hybrid WIFO network. An optical wireless receiver was designed using a Si-PIN photodiode with a sensitivity of 0.6A W at 850nm wavelength and the transmitter was implemented with an 850nm laser diode. The receiver achieved a bit error rate of 1e-9 for a data rate of 100Mbps at a non-directed line-of-sight distance of 2 meters from the transmitter. To achieve a higher data rate of 2Gbps, an integrated optical receiver was designed in 65nm CMOS. The integrated receiver consists of four low-noise trans-impedance amplifiers (TIA) whose outputs were coalesced, resulting in a 6dB higher signal-to-noise ratio than in the case of a single-TIA receiver. In this novel approach, the four trans-impedance amplifiers get their input photo-currents from four individual Si-PIN photodiodes, each with a capacitance of 1.6pF and sensitivity of 0.4A W at 850nm wavelength. The simulated input referred noise current of each TIA was 90nA over a bandwidth of 1GHz
Mass spectrometry techniques to assess the metabolism and toxicity of pharmaceutical and dietary nitrates
Get PDFNitric oxide (NO) is a signaling molecule that regulates blood pressure and vascular tone. Humans produce NO by endothelial nitric oxide synthase (eNOS), which is impaired in patients with cardiovascular disease leading to increased blood pressure, endothelial dysfunction, and an increased risk of adverse cardiovascular outcomes. Maintaining optimal levels of NO is critical for human health. Inorganic nitrate (NO3-) is reduced to NO and can be an alternate pathway to restore NO production. Diets high in nitrate reduce blood pressure and improve exercise performance in humans. In patients with advanced cardiovascular disease, organic nitrates such as nitroglycerin (glyceryl trinitrate, GTN) release NO and are essential for managing symptoms. This dissertation emphasizes mass spectrometry techniques to elucidate novel mechanisms for the effects of both organic and inorganic nitrate on cardiovascular health and exercise performance.Pharmaceutical Nitrate. Patients develop tolerance to GTN after several weeks of continuous use, limiting the potential for long-term therapy. The cause of nitrate tolerance is relatively unknown. I developed a cell culture model of nitrate tolerance that utilizes stable isotopes to measure metabolism of 15N3-GTN into 15N-nitrite. I performed global metabolomics to identify the mechanism of GTN-induced nitrate tolerance and to elucidate the protective role of vitamin C. Metabolomics demonstrated that GTN impaired purine metabolism and depleted intracellular ATP and GTP. GTN inactivated the enzyme xanthine oxidase (XO), an enzyme that is critical for the metabolism of GTN into NO. Vitamin C prevented inactivation of XO, resulting in increased NO production from GTN. Vitamin C supplementation should be further investigated as a simple and inexpensive strategy to prevent nitrate tolerance.Dietary Nitrate. Inorganic nitrate improves exercise performance by reducing the oxygen cost of exercise. Although previous research has suggested that nitrate improves mitochondrial efficiency and stimulates mitochondrial biogenesis, we have an incomplete understanding of the mechanism. In a zebrafish (Danio rerio) model, nitrate reduced the oxygen cost of exercise during a vigorous 2-hour exercise test. Although there were no significant differences in mitochondrial function between control and nitrate-treated zebrafish, nitrate treatment increased resting ADP, ATP, and cyclic AMP levels. Metabolomics analysis of whole fish illustrated that nitrate stimulated glycolysis and ketogenesis. I conclude that nitrate reduces the oxygen cost of exercise by favoring glycolysis for energy production, thereby producing more ATP while consuming less oxygen. Nitrate-stimulated alteration of metabolic fuels for energy production is a novel mechanism for the improvement in exercise performance.Summary. This dissertation is a significant contribution to scientific knowledge because of the development of a novel assay to measure 15N-labeled nitrate and nitrite, which I have applied to study the metabolism of pharmaceutical and dietary nitrates. Using metabolomics, I elucidated the novel mechanism that vitamin C prevents nitrate tolerance by protecting XO from inactivation. Furthermore, I demonstrated that nitrate alters the utilization of metabolic fuels, leading to reduced oxygen consumption during exercise.Keywords: pharmacology, zebrafish, toxicology, metabolomics, nitric oxide, nitrat
Observations on the harvesting and storing of apples from Hood River Valley
No full textPublished July 1928. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
