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An Investigation of the Impact of Distributed Flexible AC Transmission System (D-FACTS) Devices on Transmission Line Protection
No full textThis thesis explores the effects of inductive Distributed Flexible AC Transmission System (D-FACTS) device implementations on the performance of different transmission line protection schemes. The reliability and sensitivity of the trip decision of the protection elements is crucial for delivering safe and reliable power to customers. Furthermore, accurate fault location information can help significantly reduce outage duration, operating costs, and the number of consumer complaints. Inductive D-FACTS devices offer a distributed solution for managing and relieving the congestion in transmission lines. However, their interaction with protection and fault location elements may potentially cause unnecessary tripping, relay mis-operation, or misleading fault location information. The operation of these devices may also lead to unpredictable changes in transmission line impedance and fault current limitation due to their dynamic behavior before and during the disturbances. This work studies these negative aspects of D-FACTS devices and proposes solutions and alternatives to mitigate their impact. An inductive D-FACTS model was developed in the ATP version of the Electromagnetic Transients Program (EMTP) and then the steady-state performance of these devices was validated against the existing D-FACTS model in PowerWorld using the IEEE 12 bus test system. Once the model was validated, a more practical system with D-FACTS implementation is simulated using ATP. Lastly, the generated fault event files are played back into commercial relays and a protective relay software model for evaluation. This work examines the influence of two different implementations of inductive D-FACTS on the most common protection elements and schemes under different fault scenarios. The types of D-FACTS devices implementations studied were: dispersed (distributing the D-FACTS along the length of the line) and compressed (distributing them at specific distances on the line). Additionally, the impact of placing D-FACTS devices on adjacent lines was studied. Protection schemes studied in this thesis include distance elements (mho or quadrilateral elements), communication aided distance schemes (permissive overreaching transfer trip [POTT]), and fault location schemes. Furthermore, the influence of fault resistance and mutual coupling between parallel lines on relay response is studied in the presence of D-FACTS devices. Dispersed or compressed D-FACTS implementation can cause underreaching of distance elements. This may lead to a delay in the tripping time or in fact, a failure to trip in a POTT scheme. The simulation results show that using dispersed D-FACTS implementation can reduce the error compared to the compressed implementation, and increase the ability of performing correction for these devices under some operating conditions. This work also examined the effect of D-FACTS devices on distance elements' performance in presence of a fault resistance and mutual coupling between the parallel lines. The results illustrated how the direction of the power flow influences the fault resistance coverage of distance elements in the presence of D-FACTS devices. The D-FACTS may help to reduce the distance elements' underreach for forward faults and increase the underreach behavior for the reverse fault. The results show that mutual coupling influence on distance elements would be not impacted by addition of the D-FACTS devices. Lastly, we investigated how implementing inductive D-FACTS devices on the adjacent line affects the dynamic behavior of mho distance elements and the calculated effective impedance tilt of quadrilateral distance elements' response. Inserting the D-FACTS behind the relay can help expand the mho circles for forward faults and contract them for reverse faults. As a result, fault resistance coverage can be improved. On the other hand, this may cause underreaching or overreaching of the quadrilateral distance elements' response when a fault resistance is present in a ground fault. To deal with the challenges in the implementation of D-FACTS devices and minimize their influence on transmission line protection system performance, this thesis proposes mitigation for creating reliable protection and fault location schemes. The work concludes by offering recommendations for D-FACTS device implementation and protective relays' settings.doctoral, Ph.D., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2020-0
Developing a Visual Language that Combines Western and Chinese Painting
No full textTraditional Eastern and Western paintings have developed separate art forms reflective of the distinct histories, cultures, religions and geographic locations of China and the US. There are obvious differences in style due in part to distinctions in techniques, materials and the ways each culture develops and prioritizes thought and expression into the artwork. Under the relatively recent influence of global economic integration, Eastern and Western artists are drawing on each other for inspiration at an unprecedented rate. For contemporary artists, whether an artwork belongs to Eastern or Western tradition seems less important. This is true for my work, but how I evolved into this understanding came through my artistic practice. My artistic practice is focused on reconciling my Chinese roots with the expressive freedom of contemporary Western artistic expression. I create works from my observations and experiences in both cultures. My art records my real experience and understanding. I use the human figure as a vehicle to carry my soul because a naked body can hide nothing. I work with subject matter depicting opposites—things in a state of imbalance. Opposites allow for strong visual contrast and depict my beliefs. I believe our visible world (Yang) is controlled by an invisible power (Yin). A healthy society can keep the balance with the invisible power. Once this balance is broken, the invisible power will push the whole society back to the right track sooner or later by punishing or warning. Towards finding an authentic creative voice I have experimented with materials of Chinese painting and Western oil painting. I have explored what the materials of each tradition offer and understand the limits. I found that the use of fabric as a new medium allowed me to break the boundary between Eastern and Western art. It is a material that allows me to combine Chinese painting with oil painting. In my work one tradition does not dominate over the other. My practice belongs to both traditions and neither. My work is “in-between.” I call it “The Third Art.” This new art form is what I want in my heart. This thesis includes many examples of my “Combination” art practice developed during my MFA study.masters, M.A., Art & Design -- University of Idaho - College of Graduate Studies, 2020-0
On The Reliability of VANET Safety Applications for Diverse Traffic Participants
No full textDedicated Short Range Communication (DSRC) is used for wireless communication in the 5.9 GHz band that is assigned for Intelligent Transportation Systems (ITS). It allows vehicles to communicate with other vehicles (V2V) and with the infrastructure (V2I) to aid in traffic management and to reduce or avoid collisions, thereby increasing road safety. DSRC enables the establishment of Vehicular Ad-Hoc Network (VANET), which is designed for very quick message exchanges used for critical safety applications and services. In the context of connected vehicles, the focus of safety applications has mainly been on collision avoidance of motor vehicles, and little attention has been given to the safety of other participants, like bicycles. This research presents safety applications for diverse participants in connected vehicles. First a bicycle safety application is introduced that aims to reduce the so-called right hook conflict, a common collision scenario where a right-turning vehicle causes a crash with an adjacent bicycle. The information exchanged during periodic beacon messages, called Basic Safety Messages (BSMs), emitted by vehicles is used by the safety application to alert drivers of potential collisions with bicycles. The goal is to achieve this without introducing addition message overhead or deviating from existing standards. Wireless vehicle-to-vehicle communication is vulnerable to malicious jamming attacks not only for motorized vehicles, but also for any VANET participants, such as bicycles. This has potential impact on the reliability of a bicycle safety application since this application also depends on a timely reception of BSMs, that are sent periodically every 100ms. The bicycle safety application uses an algorithm that has the capability to mitigate against such attacks, as well as message loss due to natural phenomena. The algorithm was analyzed in terms of accuracy and safety application reliability. Its effectiveness was evaluated based on real-world field experiments using commercial equipment installed in the vehicles and bicycle. The research so far considered a mobility model characterized by relatively fast moving vehicles, e.g., motorized vehicles traveling at the speed limit or fast moving bicycles. Now, the traffic participants are expanded to include visually impaired persons and wheelchair users. These two new traffic participants introduce unique properties that require an investigation of Safety Applications for slow moving traffic participants. These properties are relatively low speed and the potential to turn over very short distances. We will describe scenarios using visually impaired people and wheelchair users to investigate accuracy and timeliness of OBUs heading information based on real-world field experiments. Finally VANET safety applications for scooters are investigated, which consider their unique mobility model, characterized by possible radical changes in heading over short distance at speed higher than that of pedestrians, but possibly lower than motorized vehicles. Furthermore, scooters are likely to behave rather unpredictable. They may drive close to or between vehicles, in-between lanes, or between moving traffic and parked vehicles. As this could have implications on GPS coordinate accuracy the reliability of GPS information related to the mounting point of GPS antennas on scooters in different scenarios is investigated.doctoral, Ph.D., Computer Science -- University of Idaho - College of Graduate Studies, 2020-0
Utilizing dendrochronology to investigate multiscale drivers of conifer growth in the Pacific Northwest
No full textConifers dominate temperate and boreal forests around the world and many species are economically important for structural timber production. They are also adapted to extreme climatatic conditions, such as drought and cold temperatures. Numerous conifer species occur within the Pacific Northwest United States (PNW) including firs, hemlocks, cedars, larches, and pines. The diversity of hydrologic and geographic variables across the PNW creates distinctive localized climates with differing limiting factors on conifer growth, such as temperature, moisture, and nutrient availability. Dendrochronology, or tree-ring dating, is a multidisciplinary methodology that utilizes annual tree ring widths to investigate environmental conditions influencing trees or stands throughout their life. A substantial amount of information is known about tree-growth responses to climate and stand dynamics. However, investigations into interacting silvicultural and climatological influences, as well as spatial variability of growth relationships, may inform future management and dendrochronological techniques. The first three chapters of this dissertation utilize dendrochronology to investigate multiple drivers of species-specific tree growth. The first chapter investigates the impacts of density reductions, via different thinning intensities, on tree growth in moist mixed coniferous forests in northern Idaho, USA. Species that respond rapidly to available sunlight and/or nutrients, like western larch and western redcedar, show the greatest growth increases following thinning. The less consistent responses to thinning by western hemlock and grand fir were likely due to their autecological characteristics and inherent lack of responses to greater growing space. Findings from Chapter 1 align with past thinning experiments and found that thinning is an effective tool for increasing growth in most species. However, if the objectives are to favor injury-prone and less competitive species like western hemlock and grand fir, precautions must be taken during and after treatment to limit tree damage that could produce undesired responses. Chapter 2 presents the temporal variability of growth-drought relationships for the same species from Chapter 1, and how that relationship is influenced by thinning. The four species in this study, western larch, grand fir, western redcedar, and western hemlock, show a wide range of responses to drought depending on timing of drought, length of drought, intensity of drought, and forest stand density. Findings indicate that length and season of drought, species-specific drought tolerance, and stage of stand development, influence growth-drought responses. Drought sensitivity often involves trade-offs among other limiting factors like direct competition for resources. Moreover, trees growing in moist forests may not be as highly susceptible to droughts as those in dry forests. Therefore, it is suggested that stands be managed as complex adaptive systems by prioritizing species, age, and structural diversity. Results from Chapter 1 and Chapter 2 demonstrate that strip clearcutting in moist forest results in diverse conifer species composition and structure that can be further managed to create complexity through mid-rotation thinning. Chapter 3 focused at a larger spatial scale (e.g., greater PNW) to examine the effects of geographical factors on flow-growth relationships of four different conifer species. Streamflow correlated negatively with subalpine fir and mountain hemlock growth, species commonly found at cool, moist, high elevation sites, indicating that they are likely more sensitive to severe environmental variation like those experienced with climate change. Drier-site species, Douglas-fir and ponderosa pine were mostly positively correlated with flow, though a few had significant negative correlations, indicating that they are species with high adaptive capacity. Results help simplify planning for field collections and strengthen methodologies for future streamflow reconstructions by supplying knowledge about which streams, species, elevations, and directions will yield the most robust models in the spatially diverse terrain of the PNW. Chapter 4 is a collaborative synthesis of climate change research in the Columbia River Basin (CRB). Results show that spatial distribution and thematic content of research varies across an international border, with greater concentrations of research in the United States than Canada. A general scarcity of social science research and limited interaction between social and biophysical content reinforces the need for increased collaboration between disparate disciplines. Future research focus areas should include research related to climate change adaptation and mitigation, increased integration between social and biophysical sciences, and collaborations that bridge the international border for a more unified basin-wide focus. Focusing on these new directions for research will increase the potential for science and management communities to co-produce actionable science and effective responses to climate change. With the utilization of dendrochronological techniques, many of the interacting drivers of species-specific tree growth in the PNW were discovered. Shade tolerance, disturbance dynamics, and hydroclimate all influence conifer growth in the region. The relationships between streamflow and growth are heightened for trees growing in extreme climates, and these relationships are driven by geographical features. Overall, this dissertation provides insight into dendrochronological techniques as well as silvicultural management in moist mixed conifer forests; it also lends support that forest management can assist tree growth and alter growth-drought relationships depending on species. Finally, the dissertation offers additional evidence to the decades-long theory that trees growing at the edges of their ranges show higher sensitivity to limiting factors.doctoral, Ph.D., Water Resources -- University of Idaho - College of Graduate Studies, 2020-0
Marvelous, So Marvelous: Essays, Instructions, Obituaries
No full text“Marvelous, So Marvelous: Essays, Instructions, Obituaries,” is a collection of creative nonfiction about leaking and exploding, birth and death, birds and art and monsters. The project implicates the reader through shifting subjectivities and generic indiscretion, engaging Freud and cat litter, Anne Carson and two-headed calves, Bukowski and the sublime, in an exploration of the inescapable porosity of humanness. The collection’s eight essays and one obituary invite conversation, disorientation, and identification around the indistinct edges that fail to fully separate life and death, the sacred and the profane, and the subject and the object.masters, M.F.A., English -- University of Idaho - College of Graduate Studies, 2020-0
Microglia-Specific Expression and Transcriptional Regulation of Apolipoprotein C1 (apoc1)
No full textOur recent transcriptome analysis1 found that apoc1, which encodes an apolipoprotein with poorly understood central nervous system function, is highly expressed by zebrafish microglia. We became interested in microglial expression of this gene because, APOC1 has been shown to have genetic association with human neurodegenerative diseases. Even with disease association, very little is known about the function of Apoc1 in the central nervous system. In fact, microglia-specific expression of this gene, or whether expression is developmentally regulated, has yet to be definitively demonstrated. First, we examined the orthologous relationship between human APOC1 and zebrafish apoc1 and concluded that these genes are orthologous. We characterized expression patterns of apoc1 in the developing zebrafish central nervous system using anti-sense RNA probe. Apoc1 transcript was localized to microglia in 3- and 5-day old zebrafish retina and brain. There was a dramatic increase in in apoc1 transcripts on a per microglial cell basis during development as well. We also found that apoc1 mRNA localized exclusively to microglia in adult zebrafish retinas. To provide insight into the regulation of apoc1 expression in microglia, we performed in silico analysis of the 5’ UTR and a 5kb sequence upstream of the predicted zebrafish apoc1 start site. The transcription factor (TF) binding site analysis indicated that the 5kb region upstream of apoc1 contains several predicted TF binding sites. We identified TF binding sites included those for RAR:RXR and PPARα:RXR. We therefore hypothesized that the ligands for RAR:RXR and/or PPAR:RXR nuclear receptors may modulate expression of apoc1. Using agonists of these nuclear hormone receptors, we found that apoc1 expression can be upregulated in an RXR dependent manner, but that this RXR mediated induction does not involve the RAR binding partner. Future experiments will aim to reveal the function of apoc1 expression by microglia in the CNS and its regulation. Understanding this gene may lead to further discoveries in its role in the CNS and may lead to treatments for neurodegenerative diseases.masters, M.S., Biology -- University of Idaho - College of Graduate Studies, 2020-0
Oxidation Chemistry of n-Heptane, Selected Alkyl-Esters and Biodiesels in the Low to Intermediate-Temperature Regime
No full textThis work examines the low-to-intermediate temperature combustion chemistry of long-chain alkyl esters through detailed speciation and heat release analysis in a motored engine. The data include in-cylinder pressure measurements and GC-MS analysis of the reaction end products. The fuels investigated include methyl decanoate, coconut, and canola oil methyl esters. In addition, n-heptane, known for its pronounced low-temperature oxidation features, is studied to establish a general understanding of the combustion process. For each of the fuels tested, the reaction was initiated and sustained by a gradual increase of the engine compression ratio to traverse the low-to-intermediate-temperature range. All the fuels revealed a low-temperature heat release feature. n-Heptane has the most pronounced low-temperature heat release in terms of amount and rate among the tested fuels. This was followed by methyl decanoate, coconut oil biodiesel, and canola oil biodiesel. The heat release during coconut and canola derived biodiesel combustion correlate with their saturated methyl ester content. Coconut biodiesel oxidation showed a considerable low-temperature heat release as its composition is dominated by saturated methyl esters. On the other hand, canola oil biodiesel had negligible, largely suppressed, low-temperature heat release as it consists mainly of unsaturated methyl esters. Moreover, canola biodiesel exhibited oxidation characteristics similar to unsaturated methyl esters with a centered carbon double bond. The speciation studies identified multiple oxidation end-products in the exhaust gases of the tested fuels. The concentrations of these products correlate with the extent of the low-temperature heat release of the fuel. Sixty-four intermediate species were identified in the case of coconut and canola biodiesels. It was found that the oxidation products of biodiesel are similar to that of the saturated surrogate methyl decanoate. This suggests that the saturated methyl esters content may be primarily responsible for the low-temperature heat release. The unsaturated constituents in biodiesel, do not seem to participate and may suppress the low-temperature heat generation under the current test conditions. The present work verifies the approach of modeling the biodiesel oxidation as a combination of saturated and unsaturated simple methyl esters. Unsaturated methyl ester with a centered C = C double bond exhibit similar characteristics to canola oil biodiesel and are well suited as its surrogate fuels. Furthermore, the combustion of four decanoic acid-derived alkyl esters, namely methyl, ethyl, propyl, and butyl decanoate, were investigated in a Fuel Ignition Tester (FIT) using global measurements, to infer the influence of carbon number variation for the alkyl moiety within the alkoxy group on the autoignition delay times. It was observed that increasing the alcohol chain length increased fuel reactivity. However, this enhancement diminishes as the carbon number exceeds a certain value, eventually leading to a negative impact on the ester reactivity.doctoral, Ph.D., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2020-1
Understanding and Preventing Elk Use of Agriculture Crops
No full textSince the early 1900s, elk (Cervus canadensis nelsoni) populations throughout much of the Rocky Mountain west have expanded in size and geographic range. Simultaneously, humans and agriculture production have encroached into natural elk habitat, and human-elk conflicts have arisen, most notably between elk and agriculture producers. With expanding elk populations and increasing elk-caused damages to agriculture, there remains many unresolved questions regarding: 1) the mechanisms that influence habitat selection patterns of elk in an agriculture-dominated landscape, and 2) effective deterrent treatments designed to reduce elk use of agriculture crops. To address this need, we analyzed habitat selection patterns of elk using high-frequency location data from GPS-collared elk (n = 67), which were captured in areas with high levels of elk use in agriculture throughout southern Idaho. We also tested the efficacy of two behavior-modifying deterrents, which included: 1) targeted lethal removal of elk (non-collared) actively utilizing agriculture fields; and 2) pasture fence modification with electrified wire to exclude elk from crops. We used logistic regression with the interactive effects of agriculture and time to evaluate how changes in agriculture crop phenology influence habitat selection. To evaluate the effectiveness of our targeted lethal removal deterrent treatment, we compared habitat selection patterns of GPS-collared treatment (e.g., elk treated with sharpshooting) and control elk at the summer home-range (i.e., 3rd order selection) and movement-step (i.e., 4th order selection) scale to quantify the effect of sharpshooting. We used observation survey and camera trap data to evaluate the effectiveness of our pasture fence modification treatment. We found that elk selected for areas that provided security from predators and thermal cover during the day, while foraging habitats, primarily in the form of agriculture, were selected for during the night. A strong relationship was observed between plant phenology and agriculture use with an increase in agriculture selection occurring through the growing season. Variation in life history strategies of elk emerged in our analyses, relative to the proportional use and availability of agriculture in elk home ranges. This variation in life history strategies suggest that elk can live in agriculture landscapes without relying on agriculture as a primary food source. We found that at both spatial scales, elk treated with targeted lethal removal reduced their selection of treatment fields where such treatments occurred, and movement-step scale results showed that elk treated with targeted lethal removal avoided all agriculture in general more than control elk. Our pasture fence modification treatment reduced elk use of treatment fields, but results across treatment sites varied. We found that as time since constructing the modified pasture fence increased, more elk crossed into the treatment fields. For both deterrents tested, we found they were most effective in areas where elk densities were low and alternative agriculture food sources were abundant. masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2020-1
Polyoxometalate Incorporation and Effects on Proton Transport in Hydrogel Polymers
No full textPolyoxometalate clusters embedded into hydrogel biobeads may be able to solve the challenges posed by free proton generation during remediation of trichloroethylene by acting as buffers and reducing protons to hydrogen gas. In this thesis, the challenges posed by systems that contain both diffusion and reaction processes for protons are considered mathematically, and a computer simulation to was developed to prove the relationship between diaphragm cell lag period and reactive capabilities of membranes. Two polyoxometalate compounds, sodium decavanadate and alumina sulfate, were successfully incorporated into a poly(vinyl alcohol) hydrogel membrane, and the diffusivity changes associated with each compound was determined. It was found that the diffusivity of protons through an unmodified 10\% w/v poly(vinyl alcohol) membrane was , the diffusivity through a 10\%/2\% w/w/v poly(vinyl alcohol)/sodium decavanadate membrane was , and the diffusivity through a 10\%/2\% w/w/v poly(vinyl alcohol)/alumina sulfate membrane was . Through analysis of the diaphragm cell lag period, it was found the incorporation of sodium decavanadate did not increase the reactivity of a poly(vinyl alcohol) hydrogel, and incorporation of alumina sulfate lowered the reactivity. These results indicate that polyoxometalate integration into hydrogel membranes is feasible, but does not provide any advantage to a bioremediation scenario.masters, M.S., Chemical and Materials Science Engineering -- University of Idaho - College of Graduate Studies, 2020-0