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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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Full-Text Articles in Physical Sciences and Mathematics

Stormwater Monitoring And Resident Behavior In A Semi-Arid Region, Jennifer Abraham May 2010

Stormwater Monitoring And Resident Behavior In A Semi-Arid Region, Jennifer Abraham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The combined effect of land-use alterations and introduced diffuse anthropogenic pollutants to the earth's surface in suburban/urban zones often sparks a decrease in stormwater quality in the area, and contributes to nonpoint source pollution in receiving waters. The ponds at the Utah Botanical Center (UBC) located in Kaysville, UT, regularly experience algal blooms, which in turn cause low dissolved oxygen levels in the waters, indicating high concentrations of inflowing pollutants. The goal of this thesis paper was to describe the findings from the water quality monitoring implemented at both the inlet and outlet of the UBC ponds in order to …


A Synthetic Biological Engineering Approach To Secretion- Based Recovery Of Polyhydroxyalkanoates And Other Cellular Products, Elisabeth Linton May 2010

A Synthetic Biological Engineering Approach To Secretion- Based Recovery Of Polyhydroxyalkanoates And Other Cellular Products, Elisabeth Linton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The costs associated with cellular product recovery commonly account for as much as 80% of the total production expense. As a specific example, significant recovery costs limit commercial use of polyhydroxyalkanoates (PHA), which comprise a class of microbially-accumulated polyesters. PHAs are biodegradable compounds that are of interest as a sustainable alternative to petrochemically-derived plastics. Secretion-based recovery of PHAs was studied to decrease PHA production costs. Type I and II secretory pathways are commonly used for the translocation of recombinant proteins out of the cytoplasm of E. coli. Proteins were targeted for translocation using four signal peptides (HlyA, TorA, GeneIII, …


Factors Affecting Reading Outcomes Across Time In Bureau Of Indian Education Reading First Schools, Heather J. Chapman May 2010

Factors Affecting Reading Outcomes Across Time In Bureau Of Indian Education Reading First Schools, Heather J. Chapman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Regardless of age, background, or socioeconomic status, children must learn to read in order to be successful in school and in their future careers. Reading is an essential skill necessary to be successful in all other academic content areas. Despite the importance of this skill, American Indian children consistently score below the national average on tests of reading ability and reading comprehension. During recent years, many schools in the Bureau of Indian Education (BIE) system requested funding through the Reading First initiative. Schools used the funding and support provided by the BIE Reading First grant to attempt system-wide change at …


Three Essays On Environmental- And Spatial-Based Valuation Of Urban Land And Housing, Lu Liu May 2010

Three Essays On Environmental- And Spatial-Based Valuation Of Urban Land And Housing, Lu Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation attempts to provide a comprehensive examination on the non-market valuation of the effect of open space amenities and local public infrastructure on the value of urban land and housing with both spatial heterogeneity and project heterogeneity. The demand for raw land is a derived demand for housing built on it. Therefore, we need to examine the land market and the housing market together. On the one hand, we estimate the value of urban land in a market that does not satisfy the usual assumptions of a competitive market structure as well as incentive incompatibility issues for transaction participants, …


A Spatiotemporal Analysis Of Aspen Decline In Southern Utah’S Cedar Mountain, Using Remote Sensing And Geographic Information Systems, David M. Evans May 2010

A Spatiotemporal Analysis Of Aspen Decline In Southern Utah’S Cedar Mountain, Using Remote Sensing And Geographic Information Systems, David M. Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Widespread mortality of quaking aspen (Populus tremuloides Michx.) has occurred over large expanses of the Western US during the 20th century. While much of this decline was due to conifer encroachment into seral aspen, significant aspen losses also occurred in areas of persistent aspen and may have been exasperated by drought conditions. Aspen decline has been especially notable at Cedar Mountain, Utah, an area of mostly private land and extensive persistent aspen coverage. The objectives of this study were to create a time series of live and dead aspen cover on the Cedar Mountain landscape, using remotely sensed …


Dynamics Of Van Der Waals Clusters: Theoretical And Computational Studies, Jordan Aleksander Ramilowski May 2010

Dynamics Of Van Der Waals Clusters: Theoretical And Computational Studies, Jordan Aleksander Ramilowski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The marriage of two very powerful techniques – cryogenic matrix isolation spectroscopy and seeded supersonic molecular beams – has led to the development of a novel type of cryogenic matrix isolation spectroscopy in ultracold, near 0 K, He droplets. The technique known as helium nanodroplet isolation (HENDI) has seen tremendeous experimental interest over the past 20 years; this in turn has resulted in the availability of spectroscopic data for many molecules and clusters embedded in He clusters. The experimental findings have motivated a large number of theoretical calculations. This dissertation focuses on theoretical and computational studies of the rotational dynamics …


Feasibility Of Extending An Artificial Salmon Spawning Stream, Marx Creek Near Hyder, Alaska, Tom Nelson May 2010

Feasibility Of Extending An Artificial Salmon Spawning Stream, Marx Creek Near Hyder, Alaska, Tom Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Marx Creek, near Hyder in southeast Alaska, is a groundwater-fed, artificial salmon-spawning stream that was constructed to enhance the habitat of the atypically large chum salmon. The success of the upper Marx Creek has been limited primarily by the infiltration of silty water from the Salmon River through its flood-control dike, which results in a turbid stream environment that is not conducive to salmon spawning.

The purpose of this project was to determine whether baseflow from the groundwater system is sufficient to support a proposed 1,000-foot extension of Marx Creek. The extension would be constructed approximately 500 feet east of …


Investigating Characteristics Of Lightning-Induced Transient Luminous Events Over South America, Matthew A. Bailey May 2010

Investigating Characteristics Of Lightning-Induced Transient Luminous Events Over South America, Matthew A. Bailey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sprites, halos, and elves are members of a family of short-lived, luminous phenomena known as Transient Luminous Events (TLEs), which occur in the middle atmosphere. Sprites are vertical glows occurring at altitudes typically ranging from ~40 to 90 km. In video imagery they exhibit a red color at their top, with blue tendril-like structure at low altitudes. Elves are disk-like glows that occur at the base of the ionosphere, with diameters of ~100-300 km, and have very short lifetimes (~2-3 ms). Halos are diffuse glows that occur at low altitudes, have diameters <100 km, and have a duration that may last up to 10s of ms.

A majority of the studies of TLEs have …


Analysis Of Ammonia And Volatile Organic Amine Emissions In A Confined Poultry Facility, Hanh Hong Thi Dinh May 2010

Analysis Of Ammonia And Volatile Organic Amine Emissions In A Confined Poultry Facility, Hanh Hong Thi Dinh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The National Air Emission Monitoring Study (NAEMS) project was funded by the Agricultural Air Research Council (AARC) to evaluate agricultural emissions nationwide. Utah State University (USU) is conducting a parallel study on agricultural emissions at a Cache Valley poultry facility. As part of this parallel study, samples of animal feed, eggs and animal waste were collected weekly from three manure barns (designated: manure barn, barn 4 - manure belt and barn 5 - high rise) from May 2008 to November 2009.

These samples were analyzed to determine ammonia content, total Kjeldahl nitrogen content and ammonia emission. The yearly average calculated …


An Exploratory Study On Issues And Challenges Of Agile Software Development With Scrum, Juyun Joey Cho May 2010

An Exploratory Study On Issues And Challenges Of Agile Software Development With Scrum, Juyun Joey Cho

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this dissertation was to explore critical issues and challenges that might arise in agile software development processes with Scrum. It also sought to provide management guidelines to help organizations avoid and overcome barriers in adopting the Scrum method as a future software development method. A qualitative research method design was used to capture the knowledge of practitioners and scrutinize the Scrum software development process in its natural settings. An in-depth case study was conducted in two organizations where the Scrum method was fully integrated in every aspect of two organizations' software development processes. One organization provides large-scale …


Expanding The Horizons Of Educational Pair Programming: A Methodological Review Of Pair Programming In Computer Science Education Research, Keith B. Rimington May 2010

Expanding The Horizons Of Educational Pair Programming: A Methodological Review Of Pair Programming In Computer Science Education Research, Keith B. Rimington

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Educators and researchers continue to explore the benefits, real or imagined, of implementing pair programming as part of the computer science pedagogy. Current reviews of computer science educational research practices do not focus on educational pair programming. This thesis presents a review of the research methods used in recent educational pair programming research. The primary purpose of this review is to inform the ongoing dialogue about and to provide evidence-based recommendations for improving educational pair programming research.

Replicating the design of a previous computer science education methodological review, this study inspected a sample of 108 articles from a population of …


High-Resolution Holocene Alluvial Chronostratigraphy At Archaeological Sites In Eastern Grand Canyon, Arizona, Erin Margaret Tainer May 2010

High-Resolution Holocene Alluvial Chronostratigraphy At Archaeological Sites In Eastern Grand Canyon, Arizona, Erin Margaret Tainer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the nature of Colorado River deposits in Grand Canyon helps reveal how the river responds to changes in its Colorado Plateau tributaries and Rocky Mountain headwaters. This study focused on Holocene alluvial deposits associated with archaeological sites excavated near Ninemile Draw in Glen Canyon and at Tanner Bar in eastern Grand Canyon. Two previously-developed conceptual models of deposition were tested based on previous work. Previous researchers have suggested that Holocene alluvial deposits in Grand Canyon are a series of inset aggradational packages that correlate to valley fills and arroyo-cutting cycles in Colorado Plateau tributaries and are laterally consistent throughout …


Hopping Conductivity And Charge Transport In Low Density Polyethylene, Jerilyn Brunson May 2010

Hopping Conductivity And Charge Transport In Low Density Polyethylene, Jerilyn Brunson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The properties and behaviors of charge transport mechanisms in highly insulating polymers are investigated by measuring conduction currents through thin film samples of low density polyethylene (LDPE). Measurements were obtained using a constant voltage method with copper electrodes inside a chamber adapted for measurements under vacuum and over a wide range of temperatures and applied fields. Field-dependent behaviors, including Poole-Frenkel conduction, space charge limited current (SCLC), and Schottky charge injection, were investigated at constant temperature. These field-dependent mechanisms were found to predict incorrect values of the dielectric constant and the field dependence of conductivity in LDPE was not found to …


Intercomparison Of Prism And Daymet Temperature Interpolation From 1980 To 2003, Rebecca A. Scully May 2010

Intercomparison Of Prism And Daymet Temperature Interpolation From 1980 To 2003, Rebecca A. Scully

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As ecosystem modeling becomes increasingly integrated with Geographic Information Systems (GIS) there is a rise in demand for spatially and temporally continuous meteorological data. But in order to justify management decisions or to provide robust scientific insights, the accuracy of meteorological data used as model input must be thoroughly quantified. Current methods to create spatially continuous climate data from discrete weather station data include inverse distance weighting, geostatistical techniques such as kriging and splines, local regression models such as Parameter-Elevation Regression on Independent Slope Model (PRISM) and Daymet, and regional regression models. For the conterminous United States, PRISM and Daymet …


Ecology And Seasonal Habitat Use Patterns Of Columbian Sharp-Tailed Grouse In Northern Utah, Ron D. Greer May 2010

Ecology And Seasonal Habitat Use Patterns Of Columbian Sharp-Tailed Grouse In Northern Utah, Ron D. Greer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus: hereafter sharp-tailed grouse) populations have been declining. These declines have been attributed to a number of factors, including habitat loss due to agriculture, habitat fragmentation, overgrazing by livestock, and the loss to fire.

To gather information about their status in northern Utah, I radio-marked sharp-tailed grouse in 2003 (n=15) and 2004 (n=20) in two research areas. The study areas were located on the south end of Cache County and in eastern Box Elder County. In the Cache study area, I monitored 7 males and 1 female in 2003, and 6 males and …


Computer-Aided Detection Of Breast Cancer Using Ultrasound Images, Yanhui Guo May 2010

Computer-Aided Detection Of Breast Cancer Using Ultrasound Images, Yanhui Guo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ultrasound imaging suffers from severe speckle noise. We propose a novel approach for speckle reduction using 2D homogeneity and directional average filters to remove speckle noise. We transform speckle noise into additive noise using a logarithm transformation. Texture information is employed to describe the speckle characteristics of the image. The homogeneity value is defined using texture information value, and the ultrasound image is transformed into a homogeneity domain from the gray domain. If the homogeneity value is high, the region is homogenous and has less speckle noise. Otherwise, the region is nonhomogenous, and speckle noise occurs. The threshold value is …


Critique Of A Wildlife Habitat Evaluation Method Applied To Residential Open Space, Sarah Rigard May 2010

Critique Of A Wildlife Habitat Evaluation Method Applied To Residential Open Space, Sarah Rigard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To this date, little research has been done evaluating the quality of wildlife habitat provided by open space in residential areas. Quality wildlife habitat for the purposes of this study is defined as those areas which contain the physical and biological characteristics necessary to support native wildlife species of the region. This thesis critiqued a wildlife habitat assessment method used in a nationwide study of residential open space for the purpose of better understanding the research conducted by the study and to inform similar, future habitat evaluations of landscapes altered by human activity to accommodate residential land use. The methodology …


A Singular-Value-Based Semi-Fragile Watermarking Scheme For Image Content Authentication With Tampering Localization, Xing Xin May 2010

A Singular-Value-Based Semi-Fragile Watermarking Scheme For Image Content Authentication With Tampering Localization, Xing Xin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents a novel singular-value-based semi-fragile watermarking scheme for image content authentication with tampering localization. The proposed scheme first generates a secured watermark bit sequence by performing a logical "xor" operation on a content-based watermark and content-independent watermark, wherein the content-based watermark is generated by a singular-value-based watermark bit sequence that represents intrinsic algebraic image properties, and the content-independent watermark is generated by a private-key-based random watermark bit sequence. It next embeds the secure watermark in the approximation subband of each non-overlapping 4×4 block using the adaptive quantization method to generate the watermarked image. The image content authentication process …


The Effects Of Spruce Beetle (Coleoptera: Curculionidae: Scolytinae) On Fuels And Fire In Intermountain Spruce-Fir Forests, Carl Arik Jorgensen May 2010

The Effects Of Spruce Beetle (Coleoptera: Curculionidae: Scolytinae) On Fuels And Fire In Intermountain Spruce-Fir Forests, Carl Arik Jorgensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In spruce-fir forests, there are many biotic and abiotic disturbances that can alter stand structure and composition. Many of these disturbances can produce high percentages of tree mortality at different scales. Spruce beetle has been considered a devastating disturbance agent, capable of creating high levels of mortality that will alter fuel complexes that may affect fire behavior. For comparison, stand data were gathered in endemic (near Loa and Moab, UT), epidemic (near Loa and Fairview, UT), and post-epidemic (near Salina and Loa, UT) condition classes of spruce beetle activity. Generally, fine fuels were higher during the epidemic and returned to …


A Comparative Study To Identify Factors Affecting Adoption Of Soil And Water Conservation Practices Among Smallhold Farmers In The Njoro River Watershed Of Kenya, Steven P. Huckett May 2010

A Comparative Study To Identify Factors Affecting Adoption Of Soil And Water Conservation Practices Among Smallhold Farmers In The Njoro River Watershed Of Kenya, Steven P. Huckett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Natural resource conservation is important for human well-being, especially in fragile environments of developing countries. This study occurred in 2006 among 6,500 smallhold farmers residing along a 25-km segment of a heavily utilized river. Research objectives were to determine use and adoption constraints for 14 soil and water conservation practices (SWCPs). Farms were reportedly contributing to a decline in river water quality via soil erosion. Recent occupation of the upper watershed by immigrants magnified concerns that resource degradation could escalate. A multi-method approach incorporating quantitative surveys, qualitative interviews, and participant observation was used to interpret constraining factors within the biophysical …


Goodness-Of-Fit And Change-Point Tests For Functional Data, Robertas Gabrys May 2010

Goodness-Of-Fit And Change-Point Tests For Functional Data, Robertas Gabrys

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A test for independence and identical distribution of functional observations is proposed in this thesis. To reduce dimension, curves are projected on the most important functional principal components. Then a test statistic based on lagged cross--covariances of the resulting vectors is constructed. We show that this dimension reduction step introduces asymptotically negligible terms, i.e. the projections behave asymptotically as iid vector--valued observations. A complete asymptotic theory based on correlations of random matrices, functional principal component expansions, and Hilbert space techniques is developed. The test statistic has X2-square asymptotic null distribution.

Two inferential tests for error correlation in the …


Pulsed-Laser Excited Photothermal Study Of Glasses And Nanoliter Cylindrical Sample Cell Based On Thermal Lens Spectroscopy, Prakash Raj Joshi May 2010

Pulsed-Laser Excited Photothermal Study Of Glasses And Nanoliter Cylindrical Sample Cell Based On Thermal Lens Spectroscopy, Prakash Raj Joshi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research in this dissertation presents Pulsed-Laser Excited photothermal studies of optical glasses and cylindrical sample cell.

First, a study of a photothermal lens experiment and the finite element analysis modeling for commercial colored glass filters is done. The ideal situation of a semiinfinite cylinder approximate model used to describe the photothermal lens experiment requires the boundary condition that there is no transfer of heat from the glass to surrounding when the glass is excited with a laser. The finite element analysis modeling for photothermal signal with coupling heat with surrounding shows the thermal heat transfer between the glass surface …


The Effect Of Explicit Timing On Math Performance Using Interspersal Assignments With Students With Mild/Moderate Disabilities, Fangjuan Hou May 2010

The Effect Of Explicit Timing On Math Performance Using Interspersal Assignments With Students With Mild/Moderate Disabilities, Fangjuan Hou

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Explicit timing and interspersal assignments have been validated as effective methods to facilitate students' math practice. However, no researchers have explored the combinative effect of these two methods. In Study 1, we extended the literature by comparing the effect of explicit timing with interspersal assignments, and interspersal assignments without timing. Generally, participants' rate of digits correct on easy and hard addition problems was higher during the explicit timing condition than during the untimed condition. However, the participants' rate of digits correct decreased after initial implementation of the explicit timing condition.

Motivation plays a crucial role in maintaining performance levels and …


Examination Of Deformation In Crystalline Rock From Strike-Slip Faults In Two Locations, Southern California, David H. Forand May 2010

Examination Of Deformation In Crystalline Rock From Strike-Slip Faults In Two Locations, Southern California, David H. Forand

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Damage zones adjacent to or associated with faults are important to the geologic community because of their implications to hazards and their ability to preserve evidence for, and show history of, slip, fluid flow, and deformation associated with large strike-slip faults. We examine two fault zones in southern California where fault zone damage is expressed. We revisit the drilled crystalline core from the Cajon Pass California drill hole, 4 km northeast of the San Andreas fault (SAF), and 1 km north of the Cleghorn fault, to perform a systematic structural analysis of deformation and alteration associated with strike-slip faulting at …


Classical Foundations For A Quantum Theory Of Time In A Two-Dimensional Spacetime, Nathan Thomas Carruth May 2010

Classical Foundations For A Quantum Theory Of Time In A Two-Dimensional Spacetime, Nathan Thomas Carruth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We consider the set of all spacelike embeddings of the circle S1 into a spacetime R1 × S1 with a metric globally conformal to the Minkowski metric. We identify this set and the group of conformal isometries of this spacetime as quotients of semidirect products involving diffeomorphism groups and give a transitive action of the conformal group on the set of spacelike embeddings. We provide results showing that the group of conformal isometries is a topological group and that its action on the set of spacelike embeddings is continuous. Finally, we point out some directions for future research.


Library Synthesis Of Anticancer And Antibacterial Agents Via Azide Chemistry, Jianjun Zhang May 2010

Library Synthesis Of Anticancer And Antibacterial Agents Via Azide Chemistry, Jianjun Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Various anticancer and antibacterial agents have been synthesized via azide chemistry by taking advantage of carbohydrate. Starting from the synthesis of 14 glycosyl azides, a library of carbohydrate-oxazolidinone conjugates and a library of carbohydrate-cyclopamine conjugates with biological interests were synthesized based on a highly efficient "click reaction" assisted by sonication. Some of the conjugates have improved solubility and enhanced anticancer activity.

A library of neomycin B derivatives with various modifications at the 5" position has been synthesized. Two leads exhibit prominent activity against both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Antibacterial activities were measured when combined with other …


Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards May 2010

Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While much has been written about the conflicts, supposed or actual, between logic and faith, science and religion, few accounts of the personal turmoil these conflicts can cause exist. Likewise, many of these nonfiction accounts are written from a distinctly polarized place leaning either to science or faith.

In this thesis, I mix research and history with memoir and a sense of poetry to explore my personal experience with this conflict. At its outset, I hoped for this project to capture my struggle as an orthodox member of The Church of Jesus Christ of Latter-day Saints (LDS) in dealing with …


Planning For Closure Of The Logan City/Cache County Landfill And Surrounding Landscape, Kristofor Lee Kvarfordt May 2010

Planning For Closure Of The Logan City/Cache County Landfill And Surrounding Landscape, Kristofor Lee Kvarfordt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Planning for closure requires in depth analysis into many operational, environmental, and social factors. Ideally, the planning process should resolve as many of the technical, social, and aesthetic requirements as possible by systematically addressing the various elements that influence the final design. This research identified the significant issues related to planning for the end use of the current Logan landfill after it reaches capacity in 18-20 years and the associated lagoons and wetlands. The current closure plan calls for simply recontouring the landfill to stabilize the slopes, then revegetating. The location of the site has serious implications for environmental impact …


Investigating Small-Scale Dynamical Features In The Mesopause Region, Deepak B. Simkhada May 2010

Investigating Small-Scale Dynamical Features In The Mesopause Region, Deepak B. Simkhada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Utilizing analyses of observational data, we performed a detailed study to investigate short-period atmospheric gravity waves and ripples, and instabilities in the mesopause region. Recent coordinated measurements from Haleakala Observatory, Maui, HI via airglow wave imaging, meteor wind radar, and Na wind temperature lidar have provided a unique dataset for this study. Gravity waves generated in the lower atmosphere propagate energy upwards into the mesosphere and lower thermosphere region where they modulate the airglow emissions, and later break and deposit their momentum, causing significant perturbations in winds and temperatures. Ripples, on the other hand, are likely generated by localized shear …


Random Forests Applied As A Soil Spatial Predictive Model In Arid Utah, Alexander Knell Stum May 2010

Random Forests Applied As A Soil Spatial Predictive Model In Arid Utah, Alexander Knell Stum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Initial soil surveys are incomplete for large tracts of public land in the western USA. Digital soil mapping offers a quantitative approach as an alternative to traditional soil mapping. I sought to predict soil classes across an arid to semiarid watershed of western Utah by applying random forests (RF) and using environmental covariates derived from Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and digital elevation models (DEM). Random forests are similar to classification and regression trees (CART). However, RF is doubly random. Many (e.g., 500) weak trees are grown (trained) independently because each tree is trained with a new randomly …