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Return to Riverside Poster
No full textA poster for the 2020 Return to Riverside music festival in Potlatch
High Level Examination of Am-241 as an Alternative Fuel Source in Radioisotope Thermoelectric Generators
No full textRadioisotope thermoelectric generators (RTGs) have been utilized in the USA to power satellites and other space exploration equipment for over half a century. RTGs are essential for deep space exploration where solar energy is negligible. 238Pu is the current fuel source for RTGs due to several favorable properties, such as high decay heat and minimal gamma radiation emission. The supply of 238Pu is dwindling rapidly, but 241Am has emerged as a potential substitute. We have assessed the performance of 241Am as an alternative to 238Pu by modeling the specific decay-heat and gamma spectra of several potential radioisotopes in SCALEORIGEN, and comparing these with 238Pu. An analysis of half-life, paired with decay heat and gamma output demonstrated that, of the isotopes reviewed, 241Am had the greatest potential for replacing 238Pu, with additional design considerations. 241Am had a specific decay heat about 1/5th that of 238Pu, and emits gamma radiation at about 50 keV. This leads to additional mass requirements for fuel and possibly shielding. Due to the potential health effects for operators, fabricators, and others with the potential to be exposed to these lower energy gammas, as well as impacts on sensitive electronics, we assessed radiation transport for an 241Am powered Multi-Mission Radioisotope Thermoelectric Generator. We have modeled the use of americium as a fuel source replacement for plutonium in current MMRTG designs. The assessment has been performed using MCNP6, in terms of gamma emissions that might interfere with sensitive equipment and consequently the potential for additional shielding needed to mitigate such interference. The radiation transport of the 241Am fueled model is compared with that of a 238Pu fueled model.masters, M.S., Nuclear Engineering -- University of Idaho - College of Graduate Studies, 2020-0
Verification of Red Flag Warnings Across the Northwestern U.S. as Forecasts of Large Fire Occurrence
No full textRed Flag Warnings (RFWs) issued by the National Weather Service in the United States (U.S.) are an important fire early warning system based on forecasts of critical fire weather that foster fire activity including the occurrence of large fires. However, verification of RFWs as they relate to fire activity is lacking, thereby limiting means to improve forecasts as well as increase value for end-users. We evaluated the efficacy of RFWs as forecasts of large fire occurrence for the Northwestern U.S and found favorable performance broadly across the area, along with substantial skill and improvement over reference forecasts. We further demonstrate that the skill of RFWs is significantly higher for lightning-ignited large fires and for forecasts issued during periods of high fuel dryness. The results of this first verification study of RFWs lay the groundwork for future efforts towards improving the relevance and usefulness of RFWs to better serve the fire community and public.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2020-0
Design, Modeling and Analysis of a New Power Swing Protection Scheme for Wind Integrated Systems
No full textAn increasing number of wind farms acting as power plants are connected directly to power transmission networks, supplanting conventional synchronous machine-based generation. The effect of these wind generators on the dynamic performance of the power system is becoming increasingly important as power swing rates increase with decreased system inertia. In this thesis, power swing blocking protection element operation is analyzed in context of large-scale penetration of Type 4 grid integrated wind turbine systems. The underlying converter controls for large Type 4 WTG plants are designed and integrated to 12-bus benchmark power system modeled using a Real Time Digital Simulator (RTDS). The dynamic response characteristics of the integrated wind generation systems are compared against synchronous generators during fault-contingencies by utilizing a distance protective relay model in RTDS to analyze the effective impedance seen by the relay during a power swing. Differences in the operation of the distance protection element are studied and an improved protection element is designed to ensure correct operation of the relays. The results for fault contingencies with WTG’s demonstrated the effectiveness of the protection scheme.masters, M.S., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2020-0
Network Security Monitoring for Cyber Situational Awareness
No full textModern organization networks are diverse and complex, with many different zones and security levels based on systems' functions, missions, or business purposes. This makes maintaining situational awareness of the environment both more critical and more difficult to perform. Cyber situational awareness tools are widely available making it easy to see what is happening in the network and on managed devices. At the University of Idaho, on the Idaho Falls campus, a cybersecurity research lab named the Reconfigurable Attack-Defend Instructional Computing Laboratory (RADICL) is available for research purposes. The RADICL lab is set up specifically to support cybersecurity research and training for students and the community. To make sure administrators are completely aware of what is happening in this cybersecurity lab, cyber situational awareness tools have been implemented to monitor hardware, software and network packets. When suspicious activity or malware is detected, RADICL administrators will be alerted. The purpose of this thesis is to explain in detail what cyber situational awareness tools are and provide a use case of how cyber situational tools are implemented in the RADICL lab, thus providing a possible solution for small to large businesses and similar research labs.masters, M.Engr., Computer Science -- University of Idaho - College of Graduate Studies, 2020-0
Advanced Magnetic Nanomaterials and Nanotechnology for Applications of Nuclear Radiation Detection and Ultrahigh Frequency Electronics
No full textThis dissertation presents the study on novel magnetic nanoparticles (NPs) with unique structure-property relationship. Iron based magnetic NPs for this study have been synthesized using nanocluster deposition system by soft and energetic landing on the surface of silicon substrates, and studied with respect to their nanostructures, morphologies, sizes, shapes and magnetic and electric properties for two different projects: (i) advanced nano-sensor and monitoring of radiation detection for nuclear energy applications at high temperature, and (ii) advanced magnetic nanomaterials for ultrahigh frequency electronics. In order to test the NPs compatibility for nuclear radiation detection and monitoring at high temperature, the iron-based NPs prepared using nanocluster deposition techniques by soft landing on silicon substrates were heat treated in argon, oxygen and vacuum environment up to 800 0C. The structure-property relationship pre- and post- heat treatment of the NPs have been studied. The NPs have shown stable morphology, shapes, phase and structure even up to 800 0C in vacuum environment. The results from the high temperature test and previous in-situ radiation tests are very promising for the application of the NPs as a radiation sensing material for monitoring radiation fluxes in the high temperature core of the nuclear reactors A new CMOS-integration compatible soft magnet is developed by applying energetic impact of Fe/Fe3O4 core-shell nanoparticles onto tilted Si substrates for ultrahigh frequency applications. At room temperature, the in-plane uniaxial anisotropy is induced and tuned, which is interpreted by the uniaxial shape anisotropy of the ellipsoidal nanoparticles and the nanoparticle assembly alignment. Meanwhile, excellent magnetic softness and large resistivity are obtained in the nanocomposites at 5 kV. The good and adjustable uniaxial anisotropy and magnetic softness have been obtained with the large resistivities demonstrating excellent potential for high-frequency performance in miniaturized electronic devices for next generation (5G and 6G) wireless network.doctoral, Ph.D., Physics -- University of Idaho - College of Graduate Studies, 2020-0
Schubert Varieties in the Flag Variety of Hilbert-Samuel Multiplicity Two
No full textSmooth Schubert varieties were rst characterized in terms of pattern avoidance by Lakshmibai and Sandhya. One way of classifying singularities in a variety is the Hilbert-Samuel multiplicity. We characterize the Schubert varieties of flag manifolds which have Hilbert-Samuel multiplicity two or less at all points using the Rothe diagram. Our condition is relatively simple and visually easy to distinguish given the Rothe diagram of a Schubert variety. We also show that Schubert varieties with multiplicity two or less at all points cannot be characterized by pattern avoidance.doctoral, Ph.D., Mathematics -- University of Idaho - College of Graduate Studies, 2020-0
Defining and Estimating Forest Productivity Using Multi-Point Measures and a Nonparametric Approach
No full textAccurate measures of forest site productivity are essential for forest management planning. The most common measure of site productivity is breast height age site index (BHASI) – the expected height at a reference age. Error from including early growth in productivity estimates, and limited applicability of any one BHASI model warrant development of alternative methods. Exploring alternatives may only be necessary if regional BHASI models are not accurately predicting growth rates. We compared modeled height growth rates for Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca) to felled-tree measurements to evaluate relative performance of a regional BHASI model. An orthogonal sampling design ensured samples were collected across a range of site factors known to influence Douglas-fir growth rates. Growth rates for each 10 m section were calculated and compared to BHASI modeled growth rates. The regional BHASI model under-predicted growth rates from breast height to 30 m. Observed growth rates from 10 to 30 m accounted for the majority of under-prediction relative to BHASI modeled growth rates. An alternative multi-point method of defining site productivity (10-meter site index) is described. We explored the accuracy of productivity predictions using 10-meter site index and a nonparametric approach. Using climate, soil, and topographic data along with felled tree measurements, we compared five possible models to estimate forest productivity. Model parameters, performance, and predictions were compared. Twelve validation sites were used to test accuracy of model predictions. Model performance was significantly improved when smoothing span values were optimized and elevation was added as a predictor. A four-predictor nonparametric model with a bias-corrected Akaike information criterion optimized smoothing span value produced the most accurate results and was used to produce forest productivity maps for the study area. The large resolution of currently available climatic data and the complex nature of the study area landscape necessitate a topographic variable for accurate productivity predictions. Defining productivity using 10-meter site index and estimating landscape scale productivity using an optimized nonparametric approach produced the most accurate forest productivity estimates.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2020-0
The Role of Longleaf Groundcherry (Physalis longifolia) in Zebra Chip Epidemiology
No full textThe potato psyllid (Bactericera cockerelli) has been considered a major economic pest of potato (Solanum tuberosum) for over a decade because it is associated with the “psyllid yellows” crop condition and more importantly, it is a vector of the bacterial Zebra Chip pathogen, “Candidatus Liberibacter solanacearum”. This psyllid develops on a wide range of host plants within the Solanaceae and Convolvulaceae and exists as distinct haplotypes that differ in host plant preference and use. In-field management of B. cockerelli using insecticides is not effective because B. cockerelli exists on a whole landscape level and recolonizes fields from non-crop hosts. Perennial weeds provide a ‘bridge’ between winter dormancy and the period when potato and annual weeds are available, which allow large populations of psyllids to accumulate and eventually move into potato fields during the growing season. Previous research on psyllid ecology focused primarily on the role of the perennial host plants, Lycium barbarum (matrimony vine) and Solanum dulcamara (bittersweet nightshade), as sources of psyllids colonizing potato. Both plant species are hosts for B. cockerelli but might not necessarily be the driving force of zebra chip epidemiology in Idaho; L. barbarum does not appear to be a host for “Candidatus Liberibacter solanacearum” while S. dulcamara is largely limited to riparian zones. Physalis longifolia (longleaf groundcherry) is a perennial non-crop solanaceous weedy host native to the East of the Rocky Mountains and found in all counties and states in the Pacific Northwest but has been largely overlooked by researchers as a potential host for B. cockerelli and Liberibacter. This thesis reports results from a series of field, laboratory and greenhouse experiments conducted during 2018 and 2019 to assess the host quality of P. longifolia to B. cockerelli and the zebra chip pathogen, Candidatus Liberibacter solanacearum. This thesis includes three independent chapters that are organized for submission to peer-reviewed journals. Chapter 1 reports results of B. cockerelli preference and performance assays conducted in laboratory and greenhouse settings. These assays demonstrated that P. longifolia is a better host than potato for B. cockerelli. Psyllids produce more offspring on P. longifolia than on potato and prefer P. longifolia over potato when given a choice. Plant disease susceptibility and insect disease acquisition assays showed that P. longifolia is highly susceptible to Liberibacter. The rhizomes of infected P. longifolia plants successfully overwinter and produce infected plants before potato is available, potentially allowing psyllid colonization and acquisition of the pathogen before potato is available. Chapter 2 reports results of a field survey conducted during 2018 and 2019 to confirm that B. cockerelli readily colonizes wild stands of P. longifolia. Over 200 psyllids were collected from wild P. longifolia stands in WA and ID, and many of these stands were adjacent to commercial potato fields. Molecular gut content analysis confirmed psyllid movement between P. longifolia and potato. During 2019, I was approached by a cooperator from Saltillo, Mexico to examine whether B. cockerelli that were infesting a commercial field of Physalis ixocarpa (tomatillo) were infected with Liberibacter, and whether foliar symptoms exhibited by those plants were associated with the pathogen. Results confirmed presence of Liberibacter, and gut content analysis confirmed movement between non-crop solanaceous hosts and tomatillo in Saltillo, Mexico. Results of these surveys are reported in chapter 3. Overall, the results presented provide evidence that Physalis longifolia is a metapopulation source for B. cockerelli and Liberibacter, which emphasizes the need to further evaluate more Physalis species and solanaceous weeds as hosts for B. cockerelli. Implications of these results could potentially help predict when and where infective psyllids will first colonize potato and develop landscape-level management tactics against B. cockerelli and Liberibacter.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2020-0
A COMFORT-BASED CONTROL STRATEGY IN BUILDINGS USING AN INFRARED CAMERA
No full textThis proof-of-concept study focuses on the feasibly of using a low-cost infrared camera to determine comfort conditions indoors. There are six parameters that govern the thermal comfort of an occupant which are clothing levels, metabolic activity, air velocity, relative humidity, air temperature, and the most importantly the mean radiant temperature (MRT). Almost 40% of our thermal perception of indoor surroundings occurs through radiation. The conventional thermostat measures only air temperature as a control parameter. Several studies show that air temperature alone as a control parameter causes occupant discomfort, reduces productivity, and increases energy usage in buildings. The main energy driver in buildings is thermal comfort. In this study, a comfort-based control strategy was developed based on Fanger’s Predicted Mean Vote (PMV) method. The infrared camera’s surface temperature readings were validated with thermocouple measurements and were found to be in the range of +1.23°F. We developed a spreadsheet tool in Excel to determine MRT and PMV values which agreed with the Center of Built Environment’s thermal comfort tools. Infrared images combined with machine learning techniques performed occupant detection. Energy models were used to predict energy savings and uncomfortable hours in three different climate zones in the United States with a PMV based control in comparison to conventional control. The simulation results indicated that the PMV based control maintained thermal comfort across all the locations, significantly lowered the overcooling issues dominant in conventional control, and had energy-savings at the Tampa, Florida location.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2020-0