Digital Commons Network^™

Observations Of Short Period Mesospheric Wave Patterns: In Situ Or Tropospheric Wave Generation, Michael J. Taylor, R. Edwards

All Physics Faculty Publications

Near infrared images showing wave structure in the hydroxyl (OH) nightglow emission have been obtained from Maui, Hawaii during the ALOHA‐90 campaign. Analysis of two nights during this campaign (25 and 31 March) indicate extensive, highly coherent, linear wave patterns of very short apparent period (∼5 and 10 min respectively). Both displays exhibited several features characteristic of the in situ breakdown of a large scale, long period, upper atmospheric wave disturbance. Data in support of this mechanism was found by other ALOHA instruments which detected concurrent long period (1–2 hour) mesospheric wave disturbances on both occasions. However, a tropospheric source …

Coincident Imaging And Spectrometric Observations Of Zenith Oh Nightglow Structure, Michael J. Taylor, D. N. Turnbull, R. P. Lowe

All Physics Faculty Publications

During the ALOHA‐90 campaign a novel comparative study was made between near infrared wave structure imaged in the zenith using a CCD camera and that detected at infrared wavelengths by a Fourier Transform Spectrometer. Coincident measurements were made briefly on several occasions and for an extended period on 31 March. The temporal variations imaged in the near infrared structure during this night almost completely matched those detected in the OH (3,1) band spectrometer data when similar viewing fields were compared. However, the image data also displayed small scale wave forms that were not resolved by the larger field instrument. These …

Crystal Field Splitting And Charge Flow In The Buckled-Dimer Reconstruction Of Si(100)—2× 1, G. K. Wertheim, D. Mark Riffe, J. E. Rowe, P. H. Citrin

All Physics Faculty Publications

The effect of the 2×1 reconstruction on the core-electron binding energies of the outermost Si(100) layers has been determined using high-resolution photoemission data. A previously unobserved 190-meV crystal-field splitting is resolved for the up-atoms of the asymmetric surface dimers, whose average core-level shift is -400 meV. The signal from the down-atoms is clearly identified and has a shift of +220 meV. These new findings indicate a charge flow of ∼0.05e from the subsurface to the surface layers, with a substantially larger difference of ∼0.34e between the up-atoms and down-atoms in the dimer.

Near-Infrared Imaging Of Hydroxyl Wave Structure Over An Ocean Site At Low Latitudes, Michael J. Taylor, M. J. Hill

All Physics Faculty Publications

Coordinated observations of wave structure in the near infrared hydroxyl (OH) nightglow emission have been made from Maui, Hawaii using a suite of narrow angle and all‐sky TV cameras. Two sets of data were obtained, the first in conjunction with the ALOHA‐90 campaign and the second during the subsequent new moon period. Well formed, short period (<20 min) wave patterns of comparable morphology, dynamics and abundance to those regularly imaged from mid‐latitude mountain sites were detected on several occasions. Although the Hawaiian islands comprise several high volcanic peaks, the patterns were not consistent with gravity waves generated by the interaction of strong winds with the local island topography. This suggests that other mid‐latitude wave patterns may also not be of mountain origin. The wave patterns imaged during ALOHA‐90 were of significantly lower contrast than those detected later. This effect may be related to changes in the characteristics of the middle atmosphere that occur shortly after the spring equinox.

Onset Of Convection For Autocatalytic Reaction Fronts: Laterally Bounded Systems, D. A. Vasquez, Boyd F. Edwards, J. W. Wilder

All Physics Faculty Publications

Linear hydrodynamics yields the onset of convection for ascending autocatalytic reaction fronts in laterally bounded geometries. The system is studied in the limit of infinite and zero thermal diffusivity. For convection in a vertical slab of thickness a or a long vertical cylinder of radius a, the appropriate dimensionless driving parameter scrS=δga³/νD_c involves the fractional density difference δ between the unreacted and reacted fluids, the acceleration of gravity g, the kinematic viscosity ν, and the catalyst molecular diffusivity D_c. Calculated critical values scrS_c for onset of convection agree with recent experiments on iodate–arsenous acid …

Anisotropic, Time-Dependent Solutions In Maximally Gauss-Bonnet Extended Gravity, T. Kitaura, James Thomas Wheeler

All Physics Faculty Publications

In an arbitrary number of dimensions, we find the full exact anisotropic, time-dependent, diagonal-metric solutions to maximally Gauss-Bonnet extended gravity theory. This class of theories, for which the lagrangian is an arbitrary linear combination of dimensionally extended Euler forms, is the most general gravitational theory in which the field equations contain no more than second derivatives of the metric.

We show that the space-time exponentially approaches an asymptotic state of constant, anisotropic curvature and prove three theorems concerning two generic types of singularities. The first theorem gives conditions for the existence of Kasner-like curvature singularities. For these the metric diverges …

The Interaction Of Harvester Ants And Vesicular-Arbuscular Mycorrhizal Fungi In A Patchy Environment: The Effects Of Mound Structure On Fungal Dispersion And Establishment, Carl F. Friese

Biology

The major objective of this dissertation was to describe some of the factors that may be important in the establishment of vesicular-arbuscular (VA) mycorrhizal fungi following a disturbance. The specific focus of the dissertation is primarily on the interaction of the western harvester ant and VA mycorrhizal fungi and how this interaction affects the dispersion and establishment of these mutualistic endophytes. Methods were developed to test the use of polyclonal antibodies on field and greenhouse samples. This approach proved viable and allowed me to differentiate between both the extramatrical hyphae and spores of introduced and native VA mycorrhizal fungi. I …

Creating Ethnicity In The Hydraulic Village Of The Mormon West, Charles M. Hatch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study has looked behind the mask of nineteenth-century theocracy to see Mormons in the Great Basin creating a democratic society of regionally concentrated kin groups where obligations and rewards for individuals were increasingly determined by age and life cycle position. As generations of young adults acted together in self-interest dispersing their villages on receding frontiers, they forged a balance between competition and cooperation which merged the immediate need of individuals to establish and support families with the collective memory of their Mormon past. In so doing, they created an identity for themselves which was unique in the arid West. …

Estimation Of Crop Evapotranspiration By Means Of The Penman-Monteith Equation, Paul J. Vanderkimpen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study evaluated the potential of using simple, semi-empirical resistance models for the direct estimation of crop evapotranspiration as an alternative to the traditional approach involving a reference equation and a crop coefficient. It consisted of three major parts.

The first part originally aimed at the development of simple expressions for the aerodynamic and surface resistance terms in the Penman-Monteith equation. This goal could not be achieved because of two reasons: First, the determination of aerodynamic resistance was rendered impossible because of problems with the measurements, and, secondly, the values of surface resistance, back-calculated from the Penman-Monteith equation, turned out …

Economic Strategies For White-Tailed Deer And Livestock Production On Central And South Texas Ranches, Will E. Cohen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recently, hunting and associated recreation have become an important business for Texas landowners. Most ranchers want to realize maximum net return from their investments. This study's objectives were to develop white-tailed deer (Odocoileus virginianus) and livestock enterprise budgets and to determine optimal economic combinations and levels of deer and livestock enterprises to maximize net returns. Questionnaires were mailed to landowners in the Edwards Plateau and South Texas Plains who purchased shooting preserve licenses in 1985. Five hundred and twenty-four ranchers responded (23.4%). Respondents were segregated by enterprises (deer, cattle, sheep, and Angora and Spanish goats) and a 5% …

Linear Operators Strongly Preserving Polynomial Equations Over Antinegative Semirings, Sang-Gu Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We characterized the group of linear operators that strongly preserve r-potent matrices over the binary Boolean semiring, nonbinary Boolean semirings, and zero-divisor free antinegative semirings. We extended these results to show that linear operators that strongly preserve r-potent matrices are equivalent to those linear operators that strongly preserve the matrix polynomial equation p(X) = X. where p(X) = X^r₁ + X^r₂ + ... + X^r_t and r₁>r₂>...>r_t≥2.

In addition, we characterized the group of linear operators that strongly preserve r-cyclic matrices over the same semirings. We …

A Comparison Of Estimation Procedures For The Beta Distribution, Huey Yan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The beta distribution may be used as a stochastic model for continuous proportions in many situations in applied statistics. This thesis was concerned with estimation of the parameters of the beta distribution in three different situations.

Three different estimation procedures-the method of moments, maximum likelihood, and a hybrid of these two methods, which we call the one-step improvement-were compared by computer simulation, for beta data and beta data contaminated by zeros and ones. We also evaluated maximum likelihood estimation in the context of censored data, and Newton's method as a numerical procedure for solving the likelihood equations …

Effects Of Selected Insects On Seed Production Of Hycrest Crested Wheatgrass, Ali Yusuf Issa

Biology

Studies were conducted to explore the relationship of common insect pests associated with the cultivar 'Hycrest' crested wheatgrass, Agropyron cristatum (L.) and A. desertorum (Fisher x Link). Insect population surveys were conducted on three farms during three summers to determine relative insect numbers. Thrips, Trigonotylus ruficornis, and Lygus hesperus were found to be the most abundant insect pests infesting Hycrest plants. A broad population peak was observed covering most of July through August for thrips, T. ruficornis, and L. hesperus. In addition to pest insects, the following beneficial insects were collected in significant numbers: Nabidae, Coccinellidae, Collops …

Effects Of Alternative Sprinkler Irrigation Parameters On Pesticide Movement, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill, Antonio Maria Requena, Howard M. Deer, Majid Ehteshami

Civil and Environmental Engineering Faculty Publications

The relative reduction in potential ground-water contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate infiltration depths. The movement of pesticides through soils following sprinkler irrigations was simulated with one-dimensional model. Pesticide contamination of ground water can be reduced by careful selection of pesticides, properly designed irrigation systems and improved water management techniques. Procedures for selecting an appropriate sprinkler design and pesticide are presented.

Numerical Simulation Of Saturated Flow With Fractal Analysis Of The Hydraulic Conductivity Distribution, Joan Leilani Oana

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this report is to investigate the behavior of a nonreactive contaminant in a perfectly stratified aquifer under uniform, steady-state flow. The design and the implementation of a solute transport model which characterizes the heterogeneities of the aquifer properties in a stochastic framework is reviewed. The model closely examines the advection and dispersion of the plume. The advection is the process by which the plume is transported in the aquifer by the bulk average motion of the groundwater whereas the dispersion refers to the spreading of the plume about its mean displacement position. The relationship between the fractally …

Origins Of Low-Angle Normal Faults Along The West Side Of The Bear River Range In Northern Utah, Jon E. Brummer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents new interpretations of two normal-slip, low-angle faults near Smithfield and Richmond, Utah. The faults have previously been interpreted as landslides, gravity slides, slide blocks, and depositional contacts. Recent work in the Basin and Range province allows new interpretations concerning the origins of the low­-angle faults.

Working hypotheses used to interpret origins of the faults are classified as folded thrust fault, rotated high-angle normal fault, gravity slide, listric normal fault, and low-angle normal fault. Among these general categories are several subhypotheses. The evaluation of each hypothesis includes a description of the geologic requirements of the hypothesis, a comparison …

An Ecological Test Of The Tragedy Of The Commons On Communal Rangeland In The Moroccan Western High Atlas, Lloyd Mendes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I empirically tested an hypothesis derived from a popularized version of Garrett Hardin's "Tragedy of the Commons" paradigm. Some range-development authors predict overgrazing and ecological abuse on all traditional communal rangelands. I estimated forage production, consumption, and season of use on one traditional agdal or intertribal common in the Moroccan Western High Atlas Mountains. Results from 1984-85 do not support the overgrazing predicted by "tragedy" proponents. I argue that the lack of overgrazing is not coincidental but is due to the traditional communal mechanism of controlling season of use.

Mathematical Programming Applications In Agroforestry Planning, Laurence H. Reeves

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agroforestry as a sustainable production system has been recognized as a land use system with the potential to slow encroachment of agriculture onto forested lands in developing countries. However, the acceptance of nontraditional agroforestry systems has been hampered in some areas due to the risk-averse nature of rural agriculturalists. By explicitly recognizing risk in agroforestry planning, a wider acceptance of agroforestry is possible. This thesis consists of a collection of three papers that explore the potential of modern stock portfolio theory to reduce financial risk in agroforestry planning.

The first paper presents a theoretical framework that incorporates modern stock portfolio …

Is Rainbow Trout Condition Influenced By Invertebrate-Drift Density?, Randall B. Filbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Users of the Instream Flow Incremental Methodology CTFIM) commonly assume that there is a positive linear relationship between available habitat (WUA) and stream fish biomass. However, several studies have shown a lack cf correlation between WUA and biomass. Such poor relationships may occur if other factors limit fish abundance. Food availability is a potentially important factor limiting abundance of stream fishes and can affect blomass by influencing fish condition (individual weight). I collected rainbow trout (Oncorhynchus mykiss) exposed to different levels of invertebrate-drift density to determine if condition was greater where food was more abundant. I also examined …

Hydrogen Uptake Genes And Nitrogen Fixation Efficiency Of Rhizobium Species In Symbiosis With Alfalfa, Chickpea And Pigeonpea, G. Mustafa Sajid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plasmids pDN211 and pDNll, isolated from the gene bank of the Rhizobium japonicum strain I-110, have been reported to complement two different Nif⁺ Hup^· (nitrogen fixation positive and hydrogen uptake negative) mutants. A 5.9-kb Hindiii DNA fragment of the cosmid pHU52, isolated from the gene bank of R. japonicum strain 122DES, has been reported to code for the two polypeptide subunits of uptake hydrogenase. To determine homology between the structural genes of uptake hydrogenase of the two strains, a Southern blot of the Hindiii restriction fragments of the plasmids pDN211 and pDN11 was hybridized to the 5.9-kb …

Ethical Beliefs And Practices: Do Psychologists Differ From Other Health-Care Professionals, Gary Percival

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ethical codes and principles, and laws govern the behavior of health-care professionals. Yet, the impact that ethical codes and laws have on the actual moral behaviors of health-care professionals is relatively unknown. A survey on the ethical beliefs and practices of health-care professionals was sent to the United States membership of the Association for Applied Psychophysiology and Biofeedback. AAPB's heterogeneous membership offers a unique opportunity to compare the ethical beliefs and behaviors of professionals across various health-care professions, educational levels, licensure and certification statuses, age, years in practice, and gender. The survey examined the respondents' ethical beliefs and practices in …

Instructional Logistics And Chunque-Based Learning Systems, Ian A. Mcarthur

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Existing instructional design and curriculum design strategy components were synthesized to provide a comprehensive set of design models for the development of learning systems. The term instructional logistics was coined to define the management of student progress through a series of customized learning experiences. Strategies were developed for the design of student-centered learning systems by partitioning a curriculum into meaningful and manageable pieces (called chunques) and by manipulating those pieces to create personalized and individualized paths through a series of self-contained learning experiences. Strategies were developed to organize a collection of chunques into a path based on initial simplified mental …

Factors Affecting Seeds In A Sagebrush-Steppe Ecosystem And Implications For The Dispersion Of An Annual Plant Species, Cheatgrass (Bromus Tectorum L.), Michael Ira Kelrick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated how shrub-induced spatial heterogeneity influenced and was manifested by a representative ground-story plant species at a sagebrush-steppe site in southwestern Wyoming. The dispersion of cheatgrass (Bromus tectorum) reflected differences between undershrub (higher plant densities) and interspace (between shrubs, supporting lower densities) microenvironments, hence the population ecology of this annual species served as a biological probe of shrub-associated patch structure in this community. Since cheatgrass is an annual, factors affecting the seed portion of its life cycle were of special interest. First, attributes of the above- and below-ground seed pool were characterized. The environment-wide seed depositional pattern …

A Simulation Of The Economic Effects Of Alternative Soil Types And Nitrogen Sources On Nitrate Leaching On Irrigated Agriculture In Utah, Gilbert D. Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The economic impact of reducing the amount of nitrate leached out of the root zone under irrigation in the arid West was examined. A general introduction into the nature of the problem and a review of the literature was provided in chapter I. In chapter ll the economic incentives of irrigation management were evaluated under the assumptions of both profit-maximizing and utility-maximizing (in reducing cost and effort expended in irrigation) decision-making criteria. The results indicate that there is a coincidence of interests of the farmer and the environment. Both behaviors result in less nitrate leaching than less profitable or less …

Comparison Of Laryngographic Waveforms Of An Adult And Child, Elaine Hicken

Undergraduate Honors Capstone Projects

The ability to accurately identify and differentially diagnose voice disorders is an important concern for the speech-language pathologist. This need has resulted in the development of methods which focus on identifying "objective, reliable, valid procedures for assessing voice disorders" (Costello, 1985). Several methods that allow direct observation of the laryngeal mechanism are invasive and time consuming. A method that is noninvasive and that provides valuable information about the vocal fold movement pattern is needed for clinical use.

Spacetime Dimension From A Variational Principle, D. Hochberg, James Thomas Wheeler

All Physics Faculty Publications

We consider spacetime as having an a priori arbitrary, possibly fractional dimension p>0 and propose a new variational principle for actions defined on p-dimensional spaces. Demanding that the action be stationary with respect to variations in p leads to a constraint equation whose solution yields an explicit determination of the dimension at the classical level. We illustrate these concepts by analyzing a model which reduces to free scalar field theory when p is any positive integer.

The Primary Energy Dependence Of Backscattered Electron Images Up To 100 Kev, I. Geuens, B. Nys, J. Naudts, R. Gijbels, W. Jacob, P. Van Espen

Scanning Microscopy

The backscattered electron coefficient is known to be primarily dependent on the atomic number of the sample. If the atomic number increases, the backscattered electron coefficient increases, which results in a higher intensity in the backscattered electron image. The dependence of the primary electron energy is somewhat more complicated. Using photographic material (with composition AgBr-AgI), it is seen that the contrast in the backscattered electron image increases with the primary electron energy. Using three independent methods, based on image analysis techniques, it is shown that the difference between the backscattered electron coefficient of AgBr and AgI increases with the primary …

Assessing The Effectiveness Of The Change To Technology Teacher Education, Dan L. Householder, Richard A. Boser

Engineering Education Faculty Publications

Many institutions which formerly pre-pared teachers of industrial arts are currently implementing technology teacher education programs. As these institutions change to implement technology teacher education, it is important to obtain an accurate assessment of the effectiveness of the innovation. Change in the teacher education curriculum may be assessed in a number of possible ways, each with several potential advantages. However, there is no generally accepted model for assessing the overall effectiveness of such a major change in technology teacher education. To address this problem, a study was undertaken to develop and verify a set of measures that could be used …

Electro-Optical System Design For Information Processing, Clair L. Wyatt

Utah State University Faculty Monographs

This practical text/reference provides a clear,systems-oriented approach to electro-optical system design. Covering electro-optical systems that are used for information processing,the book focuses on those systems that convey information via an electro-optical beam as in remote sensing,guidance and tracking,and fiber optic and laser communication systems. With 30% more pages,this book is a greatly expanded and revised version of the author's Radiometric System Design. Part I prepares the reader to direct and monitor the design of an electro-optical system. Part II gives detailed design considerations of the major subsystems introduced in Part I. A volume in the Optical and Electro-Optical Engineering Series.

Fluorescence Recovery After Photobleaching Techniques To Measure Translational Mobility In Microscopic Samples, Ken Jacobson, Fen Zhang, Tsong-Tseh Tsay

Scanning Microscopy

The scope of photobleaching applications and the method itself are briefly reviewed. Two current applications in this laboratory are then outlined. First, the use of spatial Fourier transforms to analyze video photobleaching measurements is presented. This method extracts diffusion coefficients using all the image data and it does not require that the initial condition created by photobleaching be known. Second, the use of genetic engineering methods coupled with photobleaching analysis is discussed as means to uncover the structural determinants of membrane protein lateral mobility.