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Designing and Developing Virtual and Real Testbeds for Industrial Control Systems Education and Training
No full textIndustrial Control Systems (ICS) are increasingly being targeted by cyber-attacks. The demand for highly qualifed cybersecurity professionals, needed to secure these systems, is at an all-time high. Current ICS cybersecurity education and training on ICS is costly and not currently available at scale. This thesis attempts to solve this problem by providing accessible training testbeds for ICS cybersecurity education. This proposed solution is covered in the span of 3 major contributions. (1) A thorough and structured literature review on the state of ICS testbeds was performed. (2) Based on those findings, a virtualized testbed, vWaterLab, meeting the common criteria of modern educational systems related to ICS, was created. (3) A detailed risk-informed design of a physically-enabled iteration of vWaterLab, called CacTiE, is provided. CacTiE, having built upon the lessons learned with vWaterLab, is more accessible and economic for smaller organizations. The construction of CacTiE is outlined and discussed.masters, M.S., Computer Science -- University of Idaho - College of Graduate Studies, 2019-1
Agricultural Insurance Loss and Relationships to Climate Across the Inland Pacific Northwest Region of the United States
No full textAgricultural crop insurance is an important component for mitigating farm risk, particularly given the potential for unexpected climatic events (Christiansen et al., 1975; Diskin, 1997; Miranda & Glauber, 1997). Using a 2.8 million insurance claim dataset from the United States Department of Agriculture (USDA), this research study examined spatiotemporal variations of agricultural insurance loss across the 24-county region of the inland Pacific Northwest (iPNW) portion of the United States, from 2001 to 2015. For the prescribed time period, wheat was a dominant crop for the region, accounting for over 700 million resulting in claims due to drought. Principal components analysis showed distinct spatial and temporal differentiations in wheat insurance losses using the range of damage causes as factor loadings, with PC1 and PC2 accounting for 75% of total variance. Of particular note were the orthogonal relationships of county-level water availability damage causes (e.g. drought and heat vs. excessive moisture and cold wet winters), which aligned with regional climatic patterns. While both 2009 and 2015 were peak years for wheat/drought insurance loss, 2015 was the only year of the two that actually experienced regional drought conditions. Given the 2008/2009 recession economic impacts (Fan et al., 2015), this comparison may indicate the unique interaction of climate and economics and their impacts on climatically based damage cause insurance filings. Extending this iPNW analysis to evaluate quantitative climatic relationships to insurance loss, we developed a design matrix methodology to identify optimum temporal windows for climate variables by county, in relationship to wheat insurance loss due to drought. The results of our temporal window construction for water availability variables (precipitation, temperature, evapotranspiration, Palmer Drought Severity Index (PDSI)) identified spatial patterns across the study area that aligned with regional climate patterns, particularly with regards to drought-prone counties of eastern Washington. Using these optimum time-lagged correlational relationships between insurance loss and individual climate variables, along with commodity pricing, we constructed a regression-based random forest model for insurance loss prediction, as well as to evaluate climatic feature importance. Our cross validated model results indicated that PDSI was the most important factor in predicting total seasonal wheat/drought insurance loss, with wheat pricing and potential evapotranspiration having noted contributions. Our overall regional model had a R2 of .45, and a RMSE of ~$8.1 million. Model performance typically underestimated annual losses, with moderate spatial variability in terms of performance between counties. Supporting our quantitative analysis of insurance loss and climate, we additionally constructed an open science-based framework for reproducibility (Flathers & Gessler, 2018; Fan et al., 2015; Dumontier & Wesley, 2018), applying our agricultural insurance loss and climate analysis as a case study example. Our case study framework implementation, which provided a set of dynamic analytics dashboards, code outputs, and reproducible research notebooks, identified several challenges that are critical for collaborative data intensive research, including: issues of data scaling, the importance of modular analytic code development, the challenges of team collaboration, data access and transformation and the difficulties regarding climatically gridded data, as well as institutional support for long term data resilience and viability.doctoral, Ph.D., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-1
ERADICATION OF ADENOCARCINOMA A549 CELLS USING 5’DFUR AND MESENCHYMAL STEM CELLS TRANSFECTED WITH THYMIDINE PHOSPHORYLASE
No full textChemotherapy drugs have been widely used for many years in cancer therapy, but produce horrible side effects like low blood cell count, nausea, and hair loss. Targeting cancer cells with a non-toxic prodrug, which is then converted to a chemotherapy drug in the vicinity of targeted cells, can largely reduce the side effects of chemotherapy. Gene-directed enzyme prodrug therapy (GDEPT) has been in development for more than 20 years as a cancer therapy approach to more effectively target tumor cells and reduce toxicity to healthy cells. Various GDEPT systems have advanced into clinical trials yet no GDEPT drug in the market indicating there are still barriers to overcome. GDEPT mainly consists of three parts to achieve the treatment: a nontoxic prodrug, a gene encoded for the enzyme which can convert the prodrug to toxicity drug, and a gene carrier. In this study, we used a well-known chemotherapy drug fluorouracil (5-FU) and its prodrug 5’DFUR, an enzyme called thymidine phosphorylase (TP), and human mesenchymal stem cells (human MSCs) as the gene carrier. A non-viral vector should be very safe for gene delivery when compared to a viral vector. One problem of using non-viral vectors (e.g., polyethylenimine) was the delivery efficiency of TP gene to human MSCs is extremely low. Since a viral vector has a much higher delivery efficiency than a non-viral vector, the viral vector containing TP gene was constructed for human MSCs gene delivery and resulted in very high delivery efficiency and subsequent protein expression. The TP gene was first delivered into A549 cells to test the cancer cell viability with 5’DFUR prodrug treatment. The TP enzyme-prodrug conversion rate in A549 cells was quantified by enzymatic assays. TP was overexpressed in A549 cells after gene delivery and converted 5’DFUR to 5-FU at a high rate, resulting in elimination of 90% of A549 cells in 4 days. Next, human MSCs infected by TP-encoded lentiviral vectors were co-cultured with A549 cells to test cell viability of both A549 cells and human MSCs after treated with prodrug 5’DFUR. Cell viability decreased to 10% in 5 days after the prodrug was administered. In summary, this study shows that prodrug 5’DFUR can be converted to chemotherapy drug 5-FU by TP-expressing human MSCs at a high rate, and results in elimination of both cancer cells and carrier cells in a short time frame.masters, M.S., Biological & Agricultural Engineering -- University of Idaho - College of Graduate Studies, 2019-1
Hydraulic Properties and Processes of Conifer Trees in the Inland Northwest Through Extended Seasonal Drought
No full textThe overarching question of this dissertation is: how do conifer trees in Northern Idaho use water across long growing seasons with little precipitation? There are four chapters, an introductory chapter first followed by three research projects. All three projects took place on the University of Idaho Experimental Forest. As in the much of the region, the soils on the experimental forest can hold large amounts of water because of their depth and composition (more than a meter-deep silt loam). Paired with a climate that allows for very little summer precipitation, the soils facilitate a slow and consistent dry down. That allowed us to study trees’ responses to drought and how they changed throughout growing seasons. The first research project described here was conducted in 2015 addresses the question: how do six of the most regionally important conifer species function from June to October of the worst drought on record? That study produced an interesting dataset that, in collaboration with Drs. Xiaonan Tai and Scott Mackay (now of University of Utah and SUNY-Buffalo, respectively), was incorporated into the TREES process-based tree physiology model. We can now model those species under different scenarios of climate and substrate. However, that project inspired a question: how do specific parameters, like whole-tree conductance, whole-tree water flux, organ conductivity, and leaf gas exchange interact through a growing season? Chapter three addresses that question by describing intensely measured water use of three individual mature P. ponderosa trees from June to October of 2017. The insights that chapter provided were then scaled up to the fourth chapter, which explores the influence that different densities of pre-commercial thinning treatments have on P. ponderosa tree hydraulic function within the same site in 2018. Each of these three research projects produced some results that were expected and consistent with literature and also some novel findings that add new insights to our understanding of conifers in the inland Northwest.doctoral, Ph.D., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-0
Comparative Study of Mg and Mg-RE Alloys for Battery Application
No full textMg-air batteries are considered important power sources especially for vehicles because of their remarkable high theoretical energy density and low cost. Mg-air batteries have a theoretical energy density of 6800Wh/kg, specific capacity of 2200 Ah/kg, and a theoretical cell voltage of 3.1V. The theoretical performance of Mg-air battery shows its comparability with Li-ion battery and can also considered better due to its low toxicity and easy availability. But, Mg-air battery has some limiting factors like low operating voltage, low columbic efficiency due to parasitic reactions such as hydrogen evolution, sluggish oxygen reduction reaction kinetics at air cathode. Our project will focus on the corrosion mechanism of magnesium and Mg-RE alloys in different electrolytes with particular reference to HER and battery discharge. The polarization behavior of different Mg-Rare earth alloys were evaluated in different heat-treated conditions and different surface conditions along with volumetric determination of hydrogen gas evolved during cathodic and anodic polarization. Mg-RE alloy ZE10A in three different heat treatment condition (a) as received, (b) heat treatment at 525o C for 8 hours and (c) 525oC for 24 hours was evaluated to observe the relationship between corrosion rate and grain size of the Mg sample. Similarly, commercial purity Mg, Mg-RE alloys ZE10Aand EV31A were evaluated in as received condition for potential application as anode for Mg-air battery. Anodic and cathodic polarization studies were performed in 0.6M NaCl, 0.5M NaNO3 and 0.1 M Na2SO4 electrolytes. Hydrogen evolved during anodic polarization was measured at different potentials and electrochemical impedance spectroscopy was carried out at open circuit conditions. The discharge behavior of lab made battery was also tested to compare the performance of the alloys in the battery. There is no unequivocal relation is available to describe the effect of grain size on the corrosion behavior. Several reports point out improvements in the corrosion resistance of the Mg alloys upon grain refinement. A decrease in the corrosion resistance has also been observed with the decrease in the grain size for different materials such as pure Mg, Al alloy, and Ni- base alloy. Ralston et al. correlated the improvement in the corrosion resistance by the grain refinement to the ability of the metal to form a protective passive layer by improved ionic conduction of the grain boundaries. The refinement of grain is generally achieved by severe plastic deformation processes such as such as surface mechanical attrition, equal channel angular pressing (ECAP), and friction stir processing. Reduction in grain size is also associated with other microstructural changes such as increased dislocation density, point defects, and creation of internal stresses during these mechanical processing techniques. Therefore, the observed changes in the corrosion behavior due to variations in the grain size cannot solely be attributed to the grain boundary structures. In order to isolate the effect of grain size, other parameters such as dislocation density, defect structures, phase content, secondary phases and their composition, shape, size, and volume fraction need to be maintained at the same level and only the grain size should vary. In this work, the effect of grain size on the corrosion of ZE10A has been investigated without subjecting the material to plastic deformation. Magnesium exhibits a phenomenon known as negative differential effect which is characterized by the increase in the rate of hydrogen evolution with increasing anodic potential. The strategy for minimizing the NDE effect would be to decrease the impurity elements to very low levels and add elements such as arsenic that will poison the hydrogen recombination and minimize the hydrogen evolution. Another strategy to minimize hydrogen evolution is to design new electrolytes. In a recent study, Richey et al showed that hydrogen evolution was the highest in 0.5 M NaCl solution and the lowest in 0.5 M NaNO3 solution. In the research, anodically polarized Mg surface was found to comprise of Mg(OH)2/MgO based bilayer film which presented a peculiar problem, as ideally a hydroxide film would slow down the kinetics of the electrochemical reaction, but it seemed to enhance the kinetics of hydrogen evolution reaction. Mg surface was found to be proportional to the rate of film growth. Many studies have shown that Mg undergoes rapid dissolution accompanied by Mg(OH)2 layer forming spontaneously upon the surface which could enhance parasitic corrosion in primary Mg batteries and affect the efficiency of Mg and decrease the life span of Mg alloys used in light weight applications. The volumetric HE collection method is used for calculation of corrosion rate during anodic polarization. The volume of the hydrogen collected is used to calculate the reduced Columbic efficiency of the battery based on the relation: Q total= QH2+Qi net anodic. The main aim of the work is to investigate the polarization behavior Mg-rare earth (RE) alloys such as ZE10A (Elektron 717) and EV31A (Elektron 21) as potential anodes for Mg-air battery, and compare their behavior with that of commercial purity Mg. The rationale behind selecting these alloys is to understand the role of Zn and Nd alloying additions on the anodic activation of the magnesium surface for battery application. Furthermore, electrochemical characterization was carried out in three different electrolytes consisting of NaCl, Na2SO4 and NaNO3 salts to understand the role of electrolyte on the NDE of the Mg-RE alloys.masters, M.Engr., Materials Science -- University of Idaho - College of Graduate Studies, 2019-0
