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Full-Text Articles in Physical Sciences and Mathematics

Characteristics Of Ungulate Behavior And Mortality Associated With Wire Fences, Justin L. Harrington May 2005

Characteristics Of Ungulate Behavior And Mortality Associated With Wire Fences, Justin L. Harrington

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the characteristics of fence mortality in pronghorn (Antilocapra americana), mule deer (Odocoileus hemionus), and elk (Cervus elaphus) along roads in Colorado and Utah from June 2004 to June 2005. I defined a direct-fence mortality as a carcass caught directly in a fence and an indirect-fence mortality as a carcass on the ground within 10 m of a fence. I estimated an average annual direct mortality occurrence of 0.25 mortalities/km (0.078 mule deer mortalities/km, 0.113 pronghorn mortalities/km, and 0.061 elk mortalities/km). The highest fence-mortality rates for ungulates occurred during August, which coincided with …


Humic And Fulvic Acids: Effects On Plant Nutrition And Growth, Jason Tew May 2005

Humic And Fulvic Acids: Effects On Plant Nutrition And Growth, Jason Tew

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Humic substances are reported to improve plant growth and nutrient uptake, with iron the most studied nutrient. The most common forms of iron in soils are iron oxides, which are stable under aerobic conditions and unavailable for plant uptake. Iron deficient plants become chlorotic, which reduces growth and yield. To determine if humic substances can reduce iron chlorosis, five commercially available organic acids were tested on maize grown in sand columns at high pH. The dry granular humic acid from Aldrich Chemical Company applied at 84.4 g/liter of sand by volume (5% by mass) and 1 g/liter added with irrigation …


Relating Bedrock Strength To Hydraulic Driving Forces Along The Large-Scale Profile Of The Colorado River In Glen And Grand Canyons, Rob D. Mackley May 2005

Relating Bedrock Strength To Hydraulic Driving Forces Along The Large-Scale Profile Of The Colorado River In Glen And Grand Canyons, Rob D. Mackley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The role of bedrock on the longitudinal profile of the Colorado River has intrigued workers for over a century. The river's profile exhibits large-scale (10 to 100 km) variations in geomorphology that are qualitatively associated with changes in rock type. This study provides the first bedrock-strength data to quantitatively test the relation of bedrock-resisting to hydraulic-driving forces in Glen and Grand canyons. The intent of this study is to explore the role, if any, that bedrock has on large-scale geomorphic variations along the profile of the Colorado River. Rock-strength data collected at 84 sites along the river corridor in Glen …


The Quaternary Tectonic And Structural Evolution Of The San Felipe Hills, California, Stefan M. Kirby May 2005

The Quaternary Tectonic And Structural Evolution Of The San Felipe Hills, California, Stefan M. Kirby

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We examine the transition between extension and strike-s lip in the San Felipe Hills, western Salton Trough, southern California using new and compiled geologic mapping, measured stratigraphic sections, magnetostratigraphy, and structural analysis. A 625 m measured section describes the Borrego, Ocotillo , and Brawley formations in the SE San Felipe Hills and constrains a regional disconformity and correlative angular unconformity at ~ 1 Ma. Sedimentation rates for the Brawley Formation above the disconformity range from 1.0 to 1.2 mm/yr, palcoflow was to the ENE. The Brawley Formation consists of three interbeddcd lithofac ics; (I) fluvial and fluvio-d eltaic, (2) lacustrinc, …


Estimation, Testing, And Monitoring Of Generalized Autoregressive Conditionally Heteroskedastic Time Series, Aonan Zhang May 2005

Estimation, Testing, And Monitoring Of Generalized Autoregressive Conditionally Heteroskedastic Time Series, Aonan Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We study in this dissertation Generalized Autoregressive Conditionally Heteroskedastic (GARCH) time series. The research focuses on squared GARCH sequences. Our main results are as follows:

1. We compare three methods of constructing confidence intervals for sample autocorrelations of squared returns modeled by models from the GARCH family. We compare the residual bootstrap, block bootstrap and subsampling methods. The residual bootstrap based on the standard GARCH(l,1) model is seen to perform best. Confidence intervals for cross-correlations of a bivariate GARCH model are also studied.

2. We study a test to discriminate between long memory and volatility changes in financial returns data. …


Examination Of Exhumed Faults In The Western San Bernardino Mountains, California: Implications For Fault Growth And Earthquake Rupture, Joseph R. Jacobs May 2005

Examination Of Exhumed Faults In The Western San Bernardino Mountains, California: Implications For Fault Growth And Earthquake Rupture, Joseph R. Jacobs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The late Miocene Cedar Springs fault system is a high-angle transpressional system in the Silverwood Lake area, western San Bernardino Mountains, southern California. This thesis presents the study of oblique-slip faults with modest amounts of slip, which represent the early stages of fault development by using slip as a proxy for maturity. A structural and geochemical characterization is provided for six fault zones ranging from 39 m of slip to 3.5 km of offset in order to develop a model of fault zone geometry and composition. Basic geometric and kinematic results are provided for an additional 29 small-displacement (cm- to …


Characterizing Deformation, Damage Parameters, And Clay Composition In Fault Zones: Insights From The Chelungpu Thrust, Taiwan, And Mozumi Right Lateral Fault, Japan, Angela J. Isaacs May 2005

Characterizing Deformation, Damage Parameters, And Clay Composition In Fault Zones: Insights From The Chelungpu Thrust, Taiwan, And Mozumi Right Lateral Fault, Japan, Angela J. Isaacs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Chelungpu thrust fault, Taiwan, and the Mozumi right-lateral fault, Japan, provide an opportunity to characterize active faults in clastic sedimentary rocks and provide constraints to seismologic models. The northern Chelungpu fault has a 10-30 m wide primary damage zone characterized by dense fractures and chemical alteration. The southern Chelungpu fault has a 25-70 m wide primary damage zone characterized by dense fractures, alteration, intensely sheared rock, and secondary faults. The complexity of the damage zone, geochemistry, and clay mineralogy of the southern fault zone reflects its greater maturity (~1 Ma) relative to the northern fault zone (~46-100 Ka). A …


Using Wavelets As A Computational And Theoretical Tool For Homogenization, Laura Lee Watkins May 2005

Using Wavelets As A Computational And Theoretical Tool For Homogenization, Laura Lee Watkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the cost of petroleum fluctuates widely, it is advisable to optimize extraction of oil and other hydrocarbon products form existing oil reserves. Because of the costs involved in recovering oil from a reservoir, predicting reservoir performance can be a useful tool for determining whether continued extraction might be profitable. This can be done using computer simulations of the physical processes involved such as pressure/head, fluid velocities, and so forth. Fluid flow within a reservoir occurs at a very small scale relative to the size of the reservoir. This size difference makes performing simulations at the physically appropriate scale unfeasible. …


Hand-Held Calculators And Mathematics Achievement: What The 1996 National Assessment Of Educational Progress Eighth-Grade Mathematics Exam Scores Tell Us, Kenneth L. Wareham May 2005

Hand-Held Calculators And Mathematics Achievement: What The 1996 National Assessment Of Educational Progress Eighth-Grade Mathematics Exam Scores Tell Us, Kenneth L. Wareham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to analyze the 1996 National Assessment of Educational Progress data to identify the relationship between calculator use and student performance on the National Assessment of Educational Progress Mathematics Assessment. This general purpose includes several sub issues. In addition to being interested in the overall relationship between use and National Assessment of Educational Progress achievement (including the effort to control for spurious factors), this study examined the contextual factors that moderate the impact of calculator use. Similarly, it analyzed the relationship between calculator use and student performance on calculator-allowed and calculator-restricted items, as well as …


Simulated Browsing Impacts On Aspen Sucker's Survival And Growth, Koketso Tshireletso May 2005

Simulated Browsing Impacts On Aspen Sucker's Survival And Growth, Koketso Tshireletso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Western forests dominated by aspen (Populus tremuloides Michx.) are highly regarded by most resource managers for their ability to provide a variety of benefits (Bartos and Mueggler 1982, Mueggler 1988). They noted aspen to be beneficial for production of livestock forage, wildlife habitat, and scenic beauty, and they are a potentially valuable source of wood products. However, in the West, communities are concerned about the dwindling acreage of aspen. The decline of aspen has been partly attributed to excessive ungulate browsing (Smith et al. 1972, Collins and Urness 1983, Bartos and Campbell 1998). Long-term grazing exclosures have also revealed …


Measurements Of The Secondary Electron Emission Properties Of Insulators, Clint D. Thomson May 2005

Measurements Of The Secondary Electron Emission Properties Of Insulators, Clint D. Thomson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Measurements of the electron-induced electron emission properties of insulators are important to many applications including spacecraft charging, scanning electron microscopy, electron sources, and particle detection technology. However, these measurements are difficult to make since insulators can charge either negatively or positively under charge particle bombardment that in turn alters insulator emissions. In addition, incident electron bombardment can modify the conductivity, internal charge distribution, surface potential, and material structure in ways that are not well understood. A primary goal of this dissertation work has been to make consistent and accurate measurements of the uncharged electron yields for insulator materials using innovative …


Identifying Temporal Trends In Treated Sagebrush Communities Using Remotely Sensed Imagery, Eric D. Sant May 2005

Identifying Temporal Trends In Treated Sagebrush Communities Using Remotely Sensed Imagery, Eric D. Sant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The sagebrush shrub steppe ecosystem is of great concern to researchers, conservationists, and the general public because of the documented declines associated with it. Monitoring in the past has generally been point-based and lacking in long-term data. To overcome these deficiencies, an automated method of monitoring was developed using GIS and remote sensing.

Geospatial layers of vegetation, soils, fire history, roads, streams, and springs were acquired and processed to characterize selected monitoring locations. A temporal set of Landsat satellite imagery for the past 30 years was normalized to reduce the effects of sun angle, haze, and sensor change. After normalization, …


Stratigraphic And Structural Analysis Of Coals In The Ferron Sandstone Member Of The Mancos Shale And Fruitland Formation: Relationship To Coal Reservoir Permeability And Coalbed Methane Production, Jason Lynn Kneedy May 2005

Stratigraphic And Structural Analysis Of Coals In The Ferron Sandstone Member Of The Mancos Shale And Fruitland Formation: Relationship To Coal Reservoir Permeability And Coalbed Methane Production, Jason Lynn Kneedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coal reservoir quality in the Ferron Sandstone Member of the Mancos Shale, and in the Fruitland Formation is dependent on coal cleat characteristics. Coal reservoir permeability increases as a result of high cleat density. From careful outcrop examination, we were able to identify several factors that increase cleat density. Vitrain coal typically has the highest fracture density as a result of having well-developed face cleats and conchoidal fractures. Clarain coal contains face and butt cleats. Cleat density in clarain is also controlled by mechanical layer thickness. As mechanical layer thickness decreases, cleat density increases. Durain and fusain coals typically contain …


The Quaternary Stratigraphy Of The Henrys Fork And Western Browns Park, Northeastern Uinta Mountains, Utah And Wyoming, Ronald C. Counts May 2005

The Quaternary Stratigraphy Of The Henrys Fork And Western Browns Park, Northeastern Uinta Mountains, Utah And Wyoming, Ronald C. Counts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The landscape evolution of the northeastern Uinta Mountains and the manner in which climatic and tectonic forcing have influenced it are not well constrained. Surficial deposits covering ~325 km2 below the glacial termini in the Henrys Fork and ~50 km2 along the Green River in western Browns Park were mapped at 1:24,000 scale to develop a Quaternary stratigraphic framework for the northeastern Uinta Mountains.

The Henrys Fork mapping area spans from late Wisconsinan moraines to Flaming Gorge Reservoir. The Henrys Fork stratigraphy contains 10 mainstem gravels, six piedmont gravels, and landslide deposits. Terraces preserved along the Henrys Fork …