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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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Hydraulic Testing Of The Big Hole Fault, Northern San Rafael Swell, Utah, William M. Schieb May 2004

Hydraulic Testing Of The Big Hole Fault, Northern San Rafael Swell, Utah, William M. Schieb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Six cross-hole packer tests were conducted at the Big Hole fault, a dip-slip normal fault in the northern San Rafael Swell of east-central Utah. Three tests were conducted at each of two locations along the fault, each location having a different total displacement. Water was injected in the footwall, hanging wall, and fault core and pressure changes were monitored in isolated intervals in the adjoining wells. Response curves were analyzed using the type curves developed by Hsieh and Neuman, and Theis, in order to evaluate the hydraulic properties of the fault and its associated damage zone.

The tests were not …


Structural Analysis Of Co2 Leakage Through The Salt Wash And Little Grand Wash Faults From Natural Reservoirs In The Colorado Plateau, Southeastern Utah, Anthony P. Williams May 2004

Structural Analysis Of Co2 Leakage Through The Salt Wash And Little Grand Wash Faults From Natural Reservoirs In The Colorado Plateau, Southeastern Utah, Anthony P. Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Little Grand Wash fault and the Salt Wash Graben in the Colorado Plateau of southeastern Utah emit CO2 gas from abandoned drillholes, springs, and a hydrocarbon seep. Similar CO2-charged water has also been emitted in the past, as shown by large localized travertine deposits and veins along and near the fault traces. The faults cut natural CO2 reservoirs and provide an excellent analog for geologic CO2 sequestration. The faults cut a north-plunging anticline of rocks consisting of siltstones, shales, and sandstones from the Permian Cutler Formation through the Cretaceous Mancos Shale. The Little Grand …


Greenstrip Establishment And Management In The Intermountain West, Brenda Kristine Younkin-Kury May 2004

Greenstrip Establishment And Management In The Intermountain West, Brenda Kristine Younkin-Kury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greenstrips were established at two sites in Utah to determine if seeded, grazed cool-season, perennial grasses would change fire behavior characteristics in areas currently dominated by Bromus tectorum. Frequency data were collected for both grazed and ungrazed seeded species and resident weed species. Moderate spring grazing did not negatively impact the establishment of seeded species at Camp Williams. Grazing at Promontory Point decreased Agropyron desertorum frequency and increased the frequency of Pascopyrum smithii. Biomass data collected for grazed and ungrazed treatments in both years indicated that moderate spring or winter grazing the first two years of establishment did …


Semilinear Elliptic Equations In Unbounded Domains, Francois A. Van Heerden May 2004

Semilinear Elliptic Equations In Unbounded Domains, Francois A. Van Heerden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied some semilinear elliptic equations on the entire space R^N. Our approach was variational, and the major obstacle was the breakdown in compactness due to the unboundedness of the domain. First, we considered an asymptotically linear Scltrodinger equation under the presence of a steep potential well. Using Lusternik-Schnirelmann theory, we obtained multiple solutions depending on the interplay between the linear, and nonlinear parts. We also exploited the nodal structure of the solutions. For periodic potentials, we constructed infinitely many homoclinic-type multibump solutions. This recovers the analogues result for the superlinear case. Finally, we introduced weights on the linear and …


Four-Dimensional Non-Reductive Homogeneous Manifolds With Neutral Metrics, Andrew Renner May 2004

Four-Dimensional Non-Reductive Homogeneous Manifolds With Neutral Metrics, Andrew Renner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A method due to É. Cartan was used to algebraically classify the possible four-dimensional manifolds that allow a (2, 2)-signature metric with a transitive group action which acts by isometries. These manifolds are classified according to the Lie algebra of the group action. There are six possibilities: four non-parameterized Lie algebras, one discretely parameterized family, and one family parameterized by R.


Lorentz Homogeneous Spaces And The Petrov Classification, Adam Bowers May 2004

Lorentz Homogeneous Spaces And The Petrov Classification, Adam Bowers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A. Z. Petrov gave a complete list of all local group actions on a four-dimensional space-time that admit an invariant Lorentz metric, up to an equivalence relation. His list was compiled by directly constructing all possible Lie algebras of infinitesimal generators of group actions that preserve a Lorentz metric. The goal of this paper was to verify that classification by algebraically constructing a list of all possible three-dimensional homogeneous spaces and calculating which among them have a non-degenerate invariant metric.


A Study Of Preservice Teachers' Attitudes Toward Human Rights And Unfair Labor Conditions: A Comparison Of The Influence Of Two Teaching Methods, Benicia D'Sa May 2004

A Study Of Preservice Teachers' Attitudes Toward Human Rights And Unfair Labor Conditions: A Comparison Of The Influence Of Two Teaching Methods, Benicia D'Sa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine the attitudes of preservice teachers towards human rights, particularly about human rights related to labor. To assess their attitudes of human rights and unfair labor conditions, two types of presentations, (a) docudrama and discussion, and (b) lecture and discussion, were conducted. The researcher evaluated these teaching methods on their efficacy in creating an awareness of human-rights violations and labor conditions. Additionally, the participants were exposed to two types of invitations to engage in human-rights advocacy.

The study involved elementary preservice teachers and secondary preservice teachers typically at the junior undergraduate level. There …


Host Shifts In Phytophagous Insects: A Mathematical Modeling Perspective, Meenakshi Venkataraman May 2004

Host Shifts In Phytophagous Insects: A Mathematical Modeling Perspective, Meenakshi Venkataraman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I explored changes in predator-prey system stability with the addition of spatial heterogeneity in prey density dependent mortality. The results indicated that this addition led to greater stability for all prey spatial distributions if prey was aggregated or loosely aggregated. These results indicated prey spatial distribution was critical to population stability. I next explored whether predator emigration under the above conditions would lead to a host shift. I used Chesson and Murdoch's templates of host density independent (HDI) aggregation and host density dependent (HDD) aggregation in predators as the basis for my metapopulation models. I varied prey density dependent mortality …


The Reliability And Validity Of The Boatwright-Bracken Child Attention Deficit Scales: Child And Parent Versions, Erica S. Thomas May 2004

The Reliability And Validity Of The Boatwright-Bracken Child Attention Deficit Scales: Child And Parent Versions, Erica S. Thomas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the psychometric properties of a new measure of attention-deficit/hyperactive disorder (ADHD) symptoms, the Boatwright-Bracken Child Attention Deficit Scale (BCADS), self- and parent-report forms. Parents and children with and without ADHD completed the BCADS to determine the reliability and validity of the BCADS. The BCADS-Child and Parent had high internal consistency reliability. The total sample parent-selfratings were moderately correlated, indicating a typical level of cross informant agreement.

Results indicate that the BCADS differentiates children with ADHD from children without ADHD. Children and parents in the clinical sample reported more symptoms of ADHD than those in the comparison sample. …


Geochemistry Of Ground Water - Surface Water Interactions And Metals Loading Rates In The North Fork Of The American Fork River, Utah, From An Abandoned Silver/Lead Mine, Neil I. Burk May 2004

Geochemistry Of Ground Water - Surface Water Interactions And Metals Loading Rates In The North Fork Of The American Fork River, Utah, From An Abandoned Silver/Lead Mine, Neil I. Burk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The aqueous geochemistry and hydrology of the North Fork of the American Fork River, its tributaries, and the ground water in the vicinity of the Pacific Mine site were investigated in order to determine what impact ground water entering the North Fork has on toxic metal loads in the river. Toxic metal contamination in the North Fork is great enough that brown and cutthroat trout have absorbed lead, cadmium, and arsenic in their tissues at concentrations that are hazardous to human health if consumed. Ground water that flows through the mine site flows directly through the mine tailings before entering …


Mitigation, Monitoring, And Geomorphology Related To Gully Erosion Of Archaeological Sites In Grand Canyon, Paul A. Petersen May 2003

Mitigation, Monitoring, And Geomorphology Related To Gully Erosion Of Archaeological Sites In Grand Canyon, Paul A. Petersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gully erosion has been damaging archaeological sites in Grand Canyon during the last several decades, and there is a need to protect these features through mitigation, monitoring, and better geomorphic understanding. The purpose of this study was to assess the effectiveness of erosion-control structures, determine the accuracy and utility of aerial photogrammetry for monitoring gullies, and understand the geomorphology of the erosion. We performed total-station surveys and other data collection during February and October, 2002, at nine study sites in eastern and western Grand Canyon.

Erosion-control structures are more prone to be damaged by flow when they are placed in …


Evaluation Of Chela Formation In Kambala-Livuite Area, Southern Block 0, Cabinda, Angola, Alba B. Bias Dos Santos May 2003

Evaluation Of Chela Formation In Kambala-Livuite Area, Southern Block 0, Cabinda, Angola, Alba B. Bias Dos Santos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The abundance of good reservoir and source rocks offshore Cabinda, Angola, makes the area an attractive and successful hydrocarbon province. Block 0, offshore Cabinda, lies in the Lower Congo basin along the western coast of Africa. The stratigraphy of Block 0 consists of two major oil-rich sequences: the rift sequence (primarily lacustrine) and the post-rift sequence (primarily marine). These are separated by a thick section of evaporites, and thus are referred to as the pre-salt sequence and post-salt sequence, respectively.

The Chela Formation, mid-Aptian in age, was deposited before the salt. It consists of sandstones and conglomerates locally interbedded with …


Quaternary Geology And Landscape Evolution Of Eastern Grand Canyon, Arizona, Matt D. Anders May 2003

Quaternary Geology And Landscape Evolution Of Eastern Grand Canyon, Arizona, Matt D. Anders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tectonics and drainage evolution are controlling overall landscape incision in eastern Grand Canyon. Superimposed on downcutting are dynamic responses of hillslopes, tributary streams, and the Colorado River to glacial-interglacial climate cycles. Five tributary stream fill terraces have been identified, and luminescence dating indicates aggradation was occurring 50- 34 ka {S3), 12-7 ka (S2), and 5-3.5 ka (S1). Seven Colorado River fill terraces have been identified, and luminescence and U-series dating indicate deposition was occurring 343-322 ka (M5), 151-118 ka (M4), and 71-64 ka (M3).

Aggradation by the Colorado River in eastern Grand Canyon begins during glacial advances and continues into …


The Relationship Between Emotional Intelligence And Adolescent Deviant Behavior, Jennifer R. Lance May 2003

The Relationship Between Emotional Intelligence And Adolescent Deviant Behavior, Jennifer R. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis summarizes a study conducted to explore the relationship between emotional intelligence and adolescent deviancy. The primary goal of this study was to investigate the relation between 1) overall emotional intelligence plus its subscales and overall normative deviant behavior, and 2) emotional intelligence subscales and subscales of a deviancy measure. Tapia's Emotional Intelligence Inventory (EII) and Vazsonyi's Normative Deviancy Scale (NDS) were used to measure the two variables of this study. Subjects included 152 high school students, aged 14-18, from a small city in Northern Utah. One hundred seventeen students came from a local high school comprising grades 10-12 …


Validation Of A Radiometric Normalization Procedure For Satellite-Derived Imagery Within A Change Detection Framework, Karin E. Callahan May 2003

Validation Of A Radiometric Normalization Procedure For Satellite-Derived Imagery Within A Change Detection Framework, Karin E. Callahan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detecting changes in land cover through time using remotely sensed imagery is a powerful application that has seen increased use as imagery has become more widely available and inexpensive. Before a time series of remotely sensed imagery can be used for change detection, images must first be standardized for effects outside of real surface change. This thesis established a validation protocol to evaluate the effectiveness of an automated technique for normalizing temporally separate but spatially coincident imagery. Using the concept of pseudo-invariant features between master-slave image pairs, spatially coincident dark and bright points are identified from images and a regression …


Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair May 2003

Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The "Den Mother" marten habitat quality models were created to provide insight into American marten habitat selection behavior and to promote the recovery of the Newfoundland marten (Martes americana atrata) population. Although these objectives are typical of most wildlife habitat modeling projects, the marten's idiosyncratic habitat ecology and apparently intractable conflicts associated with timber harvesting motivated a unique, process-oriented approach to appraising landscapes. The Den Mother models used optimal decision-making principles to synthesize critical resources (den sites and foraging opportunities) and constraints (adverse thermal situations and exposure to predations) into a single hierarchical framework. The resulting spatially explicit, …


Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz May 2003

Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the literature on plant respiration, there are two viewpoints concerning the source of respiratory control: supply (photosynthate availability) or demand (temperature dependent) limitations. While different studies indicate the primary dependency for respiration is either the supply or demand side, the two paradigms cannot both be true. The relative importance of each paradigm may depend on a number of factors including period of time during which respiration is measured, phase of plant development, environmental conditions, and species.

Studies were performed using continuous CO2 gas-exchange instrumentation to monitor short- and long-term changes in whole canopies of lettuce, tomato, soybean, and …


Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson May 2003

Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because of the scarcity of information for bird communities at the major mainland rivers of southeastern Alaska, the main objective of this study was to provide baseline information including distribution, status, and habitat associations of breeding birds.

I conducted a meta-analysis of all known reports (including the current study) conducted at major mainland rivers during the breeding season. I described bird species composition, distribution, abundance estimates, status, habitat associations, and guild membership for all birds recorded at 11 major mainland rivers. Based on incidental observations, 170 species were recorded by all studies. Of these, 134 species were known or suspected …


From The Rim To The River: The Geomorphology Of Debris Flows In The Green River Canyons Of Dinosaur National Monument, Colorado And Utah, Isaac J. Larsen May 2003

From The Rim To The River: The Geomorphology Of Debris Flows In The Green River Canyons Of Dinosaur National Monument, Colorado And Utah, Isaac J. Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Green River canyons of the eastern Uinta Mountains have experienced a 5-year period of high debris flow activity. Catchment factors were studied in watersheds and on debris fans with recent debris flows, leading to the development of a conceptual framework of the hillslope and debris flow processes that deliver sediment to the Green River. Two recent fan deposits were monitored to determine the magnitude and processes of reworking that occur during mainstem floods of varying magnitude.

The dominant debris flow initiation mechanism, termed the firehose effect, occurs when overland flow generated on bedrock slopes cascades down steep cliffs and …


On-Campus And Off-Campus Students' Ratings Of Instruction And Courses, Noriko Saeki May 2003

On-Campus And Off-Campus Students' Ratings Of Instruction And Courses, Noriko Saeki

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The associations of student ratings of instruction and courses (SRIC) with noninstructional variables (e.g., class size, expected grade) were examined in three instructional delivery groups--on-campus, off-campus face-to-face, and distance education courses. Factor analysis of SRIC from a 20-item form yielded two highly correlated factors, which differed somewhat across the groups ("Course " and "Instruction"; "Course/Instruction" and "Interaction Opportunities /Instructor Availability"; "Course/Instruction" and "Interaction Opportunities/Helpfulness"). The only educationally significant (r2 > .05) zero-order correlations were between SRIC total scores and expected grade, and were positive in all three groups (r2 = .07, .08, .06). In multiple regression analyses, …


Characteristics, Evolution, And Lateral Variation Of Lower Cretaceous Supradetachment Basins In The Daqing Shan, Inner Mongolia, China, Adrian K. Berry May 2003

Characteristics, Evolution, And Lateral Variation Of Lower Cretaceous Supradetachment Basins In The Daqing Shan, Inner Mongolia, China, Adrian K. Berry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lower Cretaceous basins associated with the Hohhot detachment in the Daqing Shan of Inner Mongolia, China, allow us to better understand the tectonic evolution of extensional basins formed in association with detachment faulting and metamorphic core complex formation. The six basins, informally named N1, N2, S1, S2, S3, and S4, are located in different structural settings, or depozones, throughout the detachment-metamorphic core complex setting, and although all basins are consistent with previously proposed models for supradetachment basin sedimentation, second-order variability in sedimentary style is exerted by these distinct structural settings. The basins are composed of coarse, predominantly footwall derived, conglomerate …


Simulation Of Groundwater Flow In Cache Valley, Utah And Idaho, Barry Myers May 2003

Simulation Of Groundwater Flow In Cache Valley, Utah And Idaho, Barry Myers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A groundwater model of Cache Valley was created using MODFLOW. Steady-state calibration of the model demonstrated that recharge to the lower confined aquifer may occur along the margin of the valley that borders the Wellsville Mountains and the Bear River Range. Steady-state calibration also showed that discharge from the unconfined aquifer may occur along the eastern and western margins of the valley in both the Utah and the Idaho portions of the valley.

Two simulations were run with increased pumping of 3 5 cubic feet per second (1 cubic meter per second) from the principal aquifer. The first simulation was …


One-Dimensional Modeling Of Bromide Tracer And Trichloroethylene Transport Based On Laboratory Experiments In Vertical Soil Columns, Keri L. Murch May 2003

One-Dimensional Modeling Of Bromide Tracer And Trichloroethylene Transport Based On Laboratory Experiments In Vertical Soil Columns, Keri L. Murch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Enhanced biodegradation using carbon donor and microbial addition is being considered as a possible remediation technique for a trichloroethylene (TCE) contaminated area in Sunset, Utah, west of the source area on Hill Air Force Base. As a precursor to any in situ remediation attempts, several laboratory treatability experiments are being conducted, including the construction of microcosms and flow-through columns. Nine large-scale flow-through columns were built using site groundwater and aquifer material. Bromide tracer tests were conducted to establish and understand the hydraulic conditions within the columns prior to the commencement of the TCE biodegradation experiments. Four predictive models were created …


Geology Of The Deseret Peak East 7.5' Quadrangle, Tooele County, Utah, And Impacts For Hydrology Of The Region, Torrey J. Copfer May 2003

Geology Of The Deseret Peak East 7.5' Quadrangle, Tooele County, Utah, And Impacts For Hydrology Of The Region, Torrey J. Copfer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detailed geologic mapping of the Deseret Peak East 7.5' Quadrangle yields new interpretations regarding the stratigraphy of the Oquirrh Basin, fault and fold geometry, and structural evolution of the region. The Stansbury Range consists of the north-south-trending Deseret anticline. Basal Mississippian units rest unconformably on Cambrian beds in the central part of the range. Paleozoic uplift, Mesozoic contraction, and Cenozoic extension have created a series of broad folds, large thrust faults, and several normal faults.

The area is dominated by bedrock springs, with the presence of abundant and thick Quaternary deposits unrelated to Pleistocene glaciation, burying drainages, and mantling hillslopes. …


Short-Term Water Use Dynamics In Drainage Lysimeters, Musa V. Dlamini May 2003

Short-Term Water Use Dynamics In Drainage Lysimeters, Musa V. Dlamini

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Turfgrass water use (seasonal turfET) and crop coefficients were determined and a mathematical soil-water balance model for non-weighing drainage lysimetcrs, which simulates the occurrence (timing and amount) of drainage, was developed. Pairs of non-weighing drainage lysimeters were used to determine crop coefficients for turfgrass in four locations in the state of Utah: Logan Golf and Country Club, Murray Golf Course, Brigham Young University (Spanish Fork) Experiment Farm, and Sunbrook Golf Course (St. George).

Daily weather data including air temperature, relative humidity, average wind travel, total solar radiation, precipitation, and average soil temperature were collected with an electronic weather station at …


The Middle Cambrian Wheeler Formation: Sequence Stratigraphy And Geochemistry Across A Ramp-To-Basin Transition, Elizabeth S. Langenburg May 2003

The Middle Cambrian Wheeler Formation: Sequence Stratigraphy And Geochemistry Across A Ramp-To-Basin Transition, Elizabeth S. Langenburg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Cambrian Wheeler Formation is interpreted as having been deposited in the shallow ramp and deeper basin environments of the House Range embayment (HRE), presumably, during a single third-order sequence. In the Drum Mountains, the Wheeler Formation (295 m thick) is dominated by proximal and distal ramp deposits; at Marjum Pass, the Wheeler Formation (190m thick) is dominated by basinal shale deposits. The Wheeler Formation contains only one biozone marker; the first appearance of Ptyhagnostus atavus. Lack of other chronostratigraphic markers and distinctive stratal patterns in the basinal facies makes correlation along this ramp-to-basin transect difficult. Therefore, carbon-isotope …


The Foraging Behavior Of A Solitary Bee, Diadasia Nigrifrons (Hymenoptera: Anthophoridae) On Sidalcea Oregana, Ssp. Oregana, Kimberly A. Kuta May 2003

The Foraging Behavior Of A Solitary Bee, Diadasia Nigrifrons (Hymenoptera: Anthophoridae) On Sidalcea Oregana, Ssp. Oregana, Kimberly A. Kuta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Foraging studies have established that bees typically obey a set of movement rules when foraging on vertical inflorescences: they begin foraging at the bottom of an inflorescence, move upward, visit a fraction of the available flowers, and leave before reaching the top of the inflorescence. These behaviors are purported to maximize bee foraging efficiency by concentrating their efforts on the most rewarding flowers and minimizing flower revisits. Bees also increase their efficiency by selecting inflorescences with many flowers, visiting more flowers per inflorescence, and remaining in resource-rich areas. To test these hypotheses on plants with more complicated flower arrangements, I …


Species Pairwise Associations Over Nine Years Of Secondary Succession: Assessing Alternative Explanations And Successional Mechanisms, Lara R. Rozzell May 2003

Species Pairwise Associations Over Nine Years Of Secondary Succession: Assessing Alternative Explanations And Successional Mechanisms, Lara R. Rozzell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance and mechanisms of species interactions are undetermined in most successional systems. I used correlations and null modeling to detect pairwise species associations between 33 plant species in the first nine years of secondary succession after logging and burning in a western Oregon Cascade forest. I tested for correlations between each species and soil nutrients, nonvegetative ground cover, and surrounding vegetation. More positive than negative associations were found at all sampling times. The proportion of positive associations decreased and negative associations increased through time. Up to 42% of associations at a sampling time were explicable by shared positive correlations …


Bootstrap Unit Root Tests For Heavy-Tailed Observations, Andrejus Parfionovas May 2003

Bootstrap Unit Root Tests For Heavy-Tailed Observations, Andrejus Parfionovas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We explore the application of the bootstrap unit root test to time series with heavy-tailed errors. The size and power of the tests are estimated for two different autoregressive models (AR(1)) using computer simulated data. Real-data examples are also presented. Two different bootstrap methods and the subsampling approach are compared. Conclusions on the optimal bootstrap parameters, the range of applicability, and the performance of the tests are made.


Identification Of Optimal Conditions For Dry Drilling (Analytical Approach To Prediction Of The Occurrence Of Bue), Prasad Gali May 2003

Identification Of Optimal Conditions For Dry Drilling (Analytical Approach To Prediction Of The Occurrence Of Bue), Prasad Gali

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lubrication is used during the drilling of aluminum to counter the formation of a built-up-edge (BUE), among other reasons. The elimination of the use of lubricants in drilling of aluminum is important because of the associated high costs of cleaning and disassembly involved in lubrication. The optimal conditions sought in this work include the elimination of the use of lubricants along with the possible attainment of a high material removal rate, which could help in reduction of cost and increase productivity at the same time. BUE has been found to be almost always present in the process of metal cutting …