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Habitat Specialists as Conservation Umbrellas: Do Areas Managed for Greater Sage-grouse Protect Pygmy Rabbits?
No full textSagebrush ecosystems are affected by a variety of factors and loss and degradation of sagebrush habitat threatens many wildlife species. Federal land management and wildlife agencies have invoked the umbrella species concept to protect this ecosystem, designating >580,000 km2 as Habitat Management Areas (HMAs) for greater sage-grouse (Centrocercus urophasianus; hereafter “sage-grosue”) putatively benefiting multiple wildlife species. The pygmy rabbit (Brachylagus idahoensis) also is a species of conservation concern due to its obligate relationship with the sagebrush ecosystem, and our goal was to evaluate the degree to which grouse-focused HMAs and distribution might serve as a conservation umbrella for pygmy rabbit habitat. We used the program Maxent to build models of varying complexity at two scales, the geographic range of pygmy rabbits, and a regional scale in east-central Idaho. Our results suggest that PHMAs encompass 59% and GHMAs encompass of 34% of primary habitat for pygmy rabbits. The SDM of habitat for pygmy rabbits can be used by land managers and biologists to prioritize survey locations for pygmy rabbits and to identify areas for habitat management, conservation, or restoration.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-0
Gravity Compensation of an Exoskeleton Joint Using Constant-Force Springs
No full textStroke is one of the leading causes of impairment in the world. Many of those who have suffered a stroke experience long-term loss of upper-limb function as a result. BLUE SABINO is an exoskeleton device being developed at the University of Idaho to help assess these patients and aid in their rehabilitation. One of the central design challenges with exoskeletons is limiting the overall weight of the device. Motors used in actuation of these devices are often oversized to allow for gravity compensation and the creation of torques that facilitate patient movements. However, if the torques required for gravity compensation are achieved through passive elastic elements, the motor and other upstream components can be lighter, potentially greatly reducing the overall weight of the device. In this paper, constant-force springs are investigated as a method of generating a constant offsetting torque to compensate for gravity. In experimental testing of multiple mounting configurations of constant-force springs (single, back-to-back, double-wrapped), the force output fluctuated less than 8.6% over 180° of wrapping, with friction values below 2.6%, validating the viability of constant-force springs for this application. The results suggest that when using multiple springs, the back-to-back configuration provides a simpler implementation with better force consistency while the double-wrapped configuration adds less friction to the system. With these results, a mechanism was created to provide a torque of 35 ± 0.7 N-m to joint 3 of the BLUE SABINO exoskeleton at all orientations of joints 1, 2, and 3 of the exoskeleton to compensate for gravity.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2019-0
Dynamic Modular Model of a Flywheel Energy Storage System
No full textHigh speed flywheel energy storage systems (HSFESS) can greatly benefit space and terrestrial applications. The development of HSFESS requires new materials that can withstand the forces acting on them at the speeds required for such applications. The design of a high performance machine also requires the characterization of saturation effects and adverse effects of iron on the air gap. In this thesis, a method is presented to account for the effects of non-ideal materials on machine design through the use of a composite loss factor. Also, a method is described that accounts for saturation and iron's effect on air gap permeance by reflecting these effects into the air gap of the machine. Modular modeling is proposed as a means to develop a tool for machine design that can evaluate various machine configurations without redevelopment of the model. This is accomplished by defining the machine as a collection of parameters that are used to define the physical interactions between the components of the system. Finally, finite element analysis is performed to verify the model developed.masters, M.Engr., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Understanding Factors Contributing to Wildland Firefighter Health, Safety, and Performance: A Pilot Study on Smokejumpers
No full textWildland firefighters have arduous and hazardous occupations and are being killed or injured at alarming rates with 1,114 killed while on assignment between 1994 and 2016. Thus, improving wildland firefighter health and safety is a National priority. Incident reports typically highlight situational awareness and communication as key factors leading to wildland firefighter injuries and death. However, important factors such as nutrition, hydration, and sleep on the fireline as well as overall fitness at other times of the year, have had limited research conducted. This research explores factors that may be leading to injuries and fatalities on the fireline. A survey was completed by 428 wildland firefighters to understand what they deem to be common contributing factors that lead to injuries and fatalities on the fireline with fatigue related to lack of sleep being one of the top self-reported factors contributing to accidents. After analysis of the survey, additional research was conducted on body composition and sleep quality and quantity to gain an understanding of what was happening physiologically on the fireline as well as gain insight on wildland firefighters sleep quality and quantity while on and off a fire assignment. This research was conducted the fire season of 2017 (June-September) with the ultimate goal of gaining a strong understanding of the self-reported factors surveyors identified in order to create future interventions that will increase wildland firefighter’s health, safety, and performance. Sleep quantity was significantly reduced on the fireline, yet sleep quality improved, like due to the firefighters being exhausted at the end of the work day. Body weights did not increase over the fire season, yet surprisingly, body fat increased significantly while lean muscle mass decreased significantly, leading researchers to believe that nutrition on the fireline played a role in these results.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2018-0
MANUFACTURING COMPLEX SURFACES TO RECREATE THE DESIGN INTENT OF LEGACY ARTIFACTS
No full textManufacturing processes and techniques have changed throughout history. When designing a product for manufacturing knowledge and availability of these processes greatly influences design even though the intent remains the same. To evaluate and compare the effects of these manufacturing processes on design two legacy artifacts were recreated using manufacturing methods that differed from the original product. These artifacts were an early 1900’s sand casted infill mallet head from the Studley Tool Cabinet, and a 1950‘s Hydro-electric dam scroll cage at 1/80th scale created using vacuum forming. This analysis resulted in seven different pieces of finished hardware using five different manufacturing methods. Three of these processes belonged to the infill mallet, and two to the scroll cage. Using these different manufacturing methods we were able to produce similar geometries of the original design while maintaining the intent of the design.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Dislocation-Based Modeling of Creep Deformation and Fracture in Modified 9Cr-1Mo Steels
No full textThe very high-temperature reactor (VHTR) represents the next generation of high temperature gas-cooled reactors designed for the future nuclear power plants. The VHTR is operated at higher pressure and temperature for longer time compared with the Pressurized Water Reactors (PWRs). Modified 9Cr-1Mo steel is a suitable candidate material for VHTR pressure vessels. Although 9Cr-1Mo steel has good creep resistance, its microstructure degrades during manufacturing processes such as welding or high temperature operation. Hence, investigating the creep resistance of welded 9Cr-1Mo steel is crucial. In this research, a micromechanical model is developed for the evaluation of creep deformation and rupture times of modified 9Cr-1Mo steel specimens. Creep deformation in metals is generally induced by dislocation generation, motion, and annihilation. Evolution of the dislocation density was modeled by considering the generation and annihilation of single and dipole dislocations. In addition to dislocation motion, there are several other factors which determine the creep resistance of this steel. Among these, the most significant are precipitate coarsening, solid solutions depletion, and void/crack nucleation and growth. The evolution of these mechanisms was accounted for by introducing specific continuum damage terms. In this study a one-dimensional (1-D) model was successfully applied to specimens made of the as-received 9Cr-1Mo steel. Comparison of the numerical model results with experimental data showed satisfactory agreement. However, a 1-D model has several limitations including applicability limitation to only 1-D stress state problems, and the inability of studying components made of more than one material. Therefore, developing a three-dimensional (3-D) comprehensive model is required to meet the objective of this research which was the prediction of creep life in welded joints made of modified 9Cr-1Mo steel. The developed 1-D model was modified and implemented in the commercial finite element software ABAQUS by means of a User Material Subroutine (UMAT). The creep of welded 9Cr-1Mo specimens was simulated by considering different material behavior in the heat affected zone (HAZ) and the welded material. Several creep experiments were conducted on 9Cr-1Mo welded specimens. The tensile creep tests were performed at a temperature range of 550-700 ˚C and stress level of 80-200 MPa. Finally, simulation results were compared to experiments, and excellent agreement was obtained between experiments and simulations.doctoral, Ph.D., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Belowground Carbon Fluxes and Changing Climatic Conditions: Evaluating Responses and Improving Mechanistic Modeling
No full textForests have an important role in the global carbon cycle, are a known regulator of climate, and are valued globally for the ecosystem services they provide to society. It is critical to improve our understanding about the exchange of carbon dioxide between forest ecosystems and Earth’s atmosphere. Specifically, there is a need for improved mechanistic understanding of the component fluxes of soil respiration (Rs): autotrophic respiration (Ra; roots and associated mycorrhizae) and heterotrophic respiration (Rh; free-living soil microbes and soil fauna involved in decomposition). We examined the responses and relative contributions of these components to manipulated soil moisture. We found that heterotrophic respiration significantly responds to moisture additions regardless of season while autotrophic respiration did not. We also found that widely used and accepted methods for survey measurements (versus automated) were not sufficient to build relationships with abiotic factors for diurnal, monthly, and annual scaling, thus eliminating commonly used gap-filling procedures. Because survey measurements are often used to validate model results, it is critical that they be done over varying time periods (some diurnal) and be paired with automated measurements. When comparing our experimental data to modeled results, we found that DayCent, a daily time-step process-based biogeochemical model, underestimates annual heterotrophic respiration by several magnitudes compared to our temperate mixed conifer forest site. This is likely because DayCent, like most traditional ecosystem models, simulates decomposition through first order kinetics which inadequately represents microbial processes. Recent research has found that including microbial mechanisms explains 20 percent more spatial heterogeneity. We manipulated the DayCent heterotrophic respiration model to include a more mechanistic representation of microbial dynamics and compared the new model with our continuous and survey observations. By using a more representative and fully calibrated model of soil carbon dynamics, we are better able to predict feedbacks between climate and soil carbon pools to inform decisions and provide benefits to society through improvements to ecosystem modeling.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2018-0
Intelligent Decimation of River Geometry Data for Manageable Use in Surface-Water Models
No full textTwo genetic algorithms (GA) for reducing river geometry data are presented. These algorithms effectively remove “redundant” and/or “nonessential” points from large datasets. The resulting smaller, less dense datasets makes the information more manageable and easier to work with. The first genetic algorithm reduces stream channel cross section data, and the second reduces bathymetry/LiDAR data. The cross-section genetic algorithm was used to reduce stream channel cross section data. A hypothetical example consisting of 41 data points and 10 cross sections on the Kootenai River in northern Idaho were reduced. Cross sections from the Kootenai River that are representative of meander, straight, braided, and canyon reaches were used to evaluate the reduction methods. The number of data points for the Kootenai River cross sections ranged from about 500 to more than 2,500. Results indicated that the genetic algorithm successfully reduced the data. However, the original genetic algorithm does not account for varying distances between the data points. To account for irregularly-spaced data, the fitness function was modified and used in subsequent analyses. Fitness values from the modified genetic algorithm were lower (better) than in the original genetic algorithm and those that used the standard method of reducing cross-section data. Visual and hydraulic analyses were also used to assess the methods. The genetic algorithm reduced cross sections approximated the shape of the original cross sections better than the standard-reduced cross sections. Also a greater number of cross-sectional data points were needed for reduced cross sections in the straight reach and even more in the meander reach because a greater amount of data points are needed to adequately define cross sections that have greater topographic variability. The effects of reduced cross-sectional data points on steady flow profiles were also analyzed. A portion of the original steady-flow model of the Kootenai River was used, consisting of thirty-five cross sections. These cross sections were reduced to 10, 20, and 30 data points by the standard and modified genetic algorithm methods, that is, six test were completed for each of the thirty-five cross sections. Differences were smaller for reduced cross sections developed by the genetic algorithm (modified) method than the standard algorithm method. Generally, differences from the original water-surface elevation were smaller as the number of data points in reduced cross sections increased, but not always, especially in the braided reach. A genetic algorithm to decimate bathymetry and Light Detection and Ranging (LiDAR) datasets was also developed. These datasets can be used in two- and three-dimensional surface-water models. A hypothetical example consisting of 961 regularly spaced data points (x, y, and z) and data taken from an actual bathymetric and LiDAR dataset (10,080 data points) were reduced. Results indicated that the genetic algorithm successfully reduced the data. Terrains produced by the genetic algorithm are fairly representative of the original data and had smaller differences (better) than standard procedures of decimating LiDAR. Hypsometric curves of volume between the GA runs and original dataset were quite similar while the curves from standard reduction methods were quite different than the original. Other x-y data also can be reduced in a method similar to that for cross section data. Also the LiDAR/bathymetric genetic algorithm should decimate equally as well on any terrain data that is expressed in x, y, and z coordinates.doctoral, Ph.D., Civil Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Searching Through the Weeds: Molecular and Bioinformatic Characterization of Solanum sisymbriifolium
No full textSolanum sisymbriifolium (SSI), also known as “Litchi Tomato” or “Sticky Nightshade,” is an undomesticated and poorly researched plant related to potato and tomato. Unlike the latter species, SSI induces eggs of the cyst nematode, Globodera pallida, to hatch and migrate into its roots, but then arrests further nematode maturation. In order to provide researchers with a partial blueprint of its genetic make-up so that the mechanism of this response might be identified, we used single molecule real time (SMRT) sequencing to compile a high quality de novo transcriptome of 41,189 unigenes drawn from individually sequenced bud, root, stem, and leaf RNA populations. Functional annotation and BUSCO analysis showed that this transcriptome was surprisingly complete, even though it represented genes expressed at a single time point. By sequencing the 4 organ libraries separately, we found we could get a reliable snapshot of transcript distributions in each organ. A divergent site analysis of the merged transcriptome indicated that this species might have undergone a recent genome duplication and re-diploidization. Further analysis indicated that the plant then retained a disproportionate number of genes associated with photosynthesis and amino acid metabolism in comparison to genes with characteristics of R-proteins or involved in secondary metabolism. The former processes may have given SSI a bigger competitive advantage than the latter did. Further, SSI was found to be representative of some undomesticated plant species that appear to be recalcitrant to Agrobacterium-mediated infection. Transient expression assays in this weed using β-glucuronidase expression have proven highly variable and often failed. Systematic optimization experiments revealed that reducing wounding when bacteria were applied reduced variability. Transfection levels were also influenced by the number of leaves infected/plant, and by total leaves at the time of infection. This inverse relationship between leaf number and GUS expression resembled age-related resistance, but did not correlate with flowering, the accumulation of SA during bac infection, or with overt signs of senescence.doctoral, Ph.D., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2018-0
Changes in Knowledge of the Female Athlete Triad among Female High School Athletes Following a Brief Nutrition Education Intervention
No full textThe Female Athlete Triad (Triad) is a disorder comprised of three conditions: low energy availability, menstrual irregularity, and decreased bone mineral density. Triad prevalence is high among high school athletes, though their knowledge of the disorder is low. This study aimed to determine whether viewing a nutrition education video including Registered Dietitians describing Triad etiology, progression, and prevention, as well as testimonies of former college athletes who experienced the Triad would change knowledge of the Triad among female high school athletes. Ninety-three female athletes (15.89 ± 1.2 years) from four North Idaho high schools consented to participate. Following randomization to the intervention or control group, all participants completed a pre-survey with ten Triad knowledge questions highlighting Triad risk factors and consequences. Each question was answered using a Likert scale (“strongly disagree” to “strongly agree”). The intervention group (n = 46) then viewed the nutrition education video, while the control group (n = 44) played a nutrition game in another room. Immediately after, all participants completed a post-survey containing the same ten Triad knowledge questions. Correct responses received one point; each participant received a score out of ten on each survey. Results of Mann-Whitney U tests revealed that pre-survey Triad knowledge scores between groups were similar, though post-survey scores were significantly higher among the intervention group as compared to the control (mean rank 64.07 vs. 26.09 respectively; U = 158.00; p ˂ 0.001). The Triad video may be considered for use in high school athletic programs to increase Triad knowledge among female athletes.masters, M.S., Family and Consumer Sciences -- University of Idaho - College of Graduate Studies, 2018-0