Physical Sciences and Mathematics Commons^™

The Time-Dependent Ionospheric Model Using A Tec-Driven Servo: An Investigation Of The Capabilities And Limitations, Jenny Rebecca Whiteley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ionosphere is a region of the atmosphere with a high density of electrons. These electrons affect the behavior of any electromagnetic wave that passes through the ionosphere. Communication and geolocation systems, such as traditional radio and Global Positioning Systems, depend on emitted electromagnetic signals being picked up by a receiver. The presence of the ionosphere affects the behavior of the signal and the quality of the service. Hence, the interactions between electromagnetic waves and the ionosphere provide a major motivation to understand, research, and successfully model and predict the ionosphere and its physical phenomena. This study focused on determining …

Tdim Ionospheric Model Tec, Hmf2, And Nmf2 At Mid-Latitude Northern Hemisphere, Used In The Paper Titled "Is Tec A Viable Servo Input?", Jan J. Sojka

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The externally imposed vertical drift in the F region is an extremely important driver of ionospheric dynamics but is very difficult to measure or map. Ionospheric servo algorithms have used hmF2 as F-region observable to infer the vertical drift. However, an even more plentiful observable is the total electron content (TEC) whose coverage over northern mid-latitudes has both spatial and temporal availability that matches those of the probable mechanisms responsible for vertical drift dynamics.

This ionospheric, first principle physics, study shows that TEC is a viable servo parameter at mid-latitudes in the noon sector. The servo relationship is shown to …

Individual Variation And Ecotypic Niches In Simulations Of The Impact Of Climatic Volatility, George P. Malanson, R. Justin Derose, Matthew F. Bekker

Wildland Resources Faculty Publications

Expectations of the impacts of climatic variation on species can depend on whether and how intraspecific variability is incorporated in models. Coefficients of variation from tree-ring records of Pinus albicaulis through time and across space were used to parameterize volatility and individuality, respectively. The records across sites were used to differentiate the average modes on an environmental gradient for Gaussian fitness of ecotypic niches, and to add further individual variation in mode and standard deviation of these functions in individual-based Monte Carlo simulations of reproduction and mortality with inheritance of individual variability. Ecotypic gamma and Shannon diversity decreased with volatility …

Combining Geographic Information Systems And Agent-Based Models In Archaeology: Part 2 Of 3, Benjamin Davies, Iza Romanowska, Kathryn Harris, Stefani Crabtree

Environment and Society Faculty Publications

Archaeologists are using spatial data in increasingly sophisticated analyses and invoking more explicit considerations of space in their interpretations. Geographic information systems (GIS) have become standard technology for professional archaeologists in the collection and management of spatial data. Many calls have been made to develop and adapt digital geospatial technologies for interpretation and understanding past social dynamics, but this has been limited to some extent by the static nature of map-oriented GIS approaches. Here, we illustrate how coupling GIS with agent-based modeling (ABM) can assist with more dynamic explorations of past uses of space and geospatial phenomena.

Comparing Performance Of Gene Set Test Methods Using Biologically Relevant Simulated Data, Richard M. Lambert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Today we know that there are many genetically driven diseases and health conditions. These problems often manifest only when a set of genes are either active or inactive. Recent technology allows us to measure the activity level of genes in cells, which we call gene expression. It is of great interest to society to be able to statistically compare the gene expression of a large number of genes between two or more groups. For example, we may want to compare the gene expression of a group of cancer patients with a group of non-cancer patients to better understand the genetic …

A Model For Bioaugmented Anaerobic Granule, Amitesh Mahajan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this study, we have created a simulation model which is concerned about digesting cellulose, as a major component of microalgae in a bioreactor. This model is designed to generate a computational model that simulates the process of granulation in anaerobic sludge and aims to investigate scenarios of possible granular bioaugmentation. Once a mature granule is formed, protein is used as an alternative substrate that will be supplied to a mature granule. Protein, being a main component of cyanobacteria, will promote growth and incorporation of a cell type that can degrade protein (selective pressure). The model developed in a cDynoMiCs …

Peer-To-Peer Simulation Of Massive Virtual Environments, James Dean Mathias

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Massively multiplayer games make up a large and growing segment of the computer game industry. One of the best known examples of these games is World of Warcraft, developed and published by Activision Blizzard. World of Warcraft boasts a subscriber base of over eleven million active subscribers, earning an estimated $1 billion dollars in 2010.

Some of the core issues for companies that publish these games are the cost of the computers, Internet bandwidth usage, and supporting technical staff. These costs easily reach hundreds of thousands of dollars each month, and in the case of World of Warcraft, millions of …

Simulation Chamber For Space Environment Survivability Testing, Lisa Montierth, Robert H. Johnson, John R. Dennison, James Dyer

All Physics Faculty Presentations

A vacuum chamber was designed and built that simulates the space environment making possible the testing of material modification due to exposure of solar radiation. Critical environmental components required include an ultra high vacuum (10-9 Torr), a UV/VIS/NIR solar spectrum source, an electron gun and charge plasma, temperature extremes, and long exposure duration. To simulate the solar spectrum, a solar simulator was attached to the chamber with a range of 200nm to 2000nm. The exposure time can be accelerated by scaling the solar intensity up to four suns. A Krypton lamp imitates the 120 nm ultraviolet hydrogen Lymann alpha emission …

Small Scale Simulation Chamber For Space Environment Survivability Testing, Robert H. Johnson, Lisa D. Montierth, John R. Dennison, James S. Dyer, Ethan Lindstrom, Alex Chanson

All Physics Faculty Publications

A versatile vacuum system for long duration testing of materials modifications due to exposure to simulated space environment conditions has been designed and built. The chamber is particularly well suited for cost-effective tests of multiple small scale materials samples over prolonged exposure. Critical environmental components simulated include neutral gas [ultrahigh vacuum (10-7 Pa) to ambient], FUV/UV/VIS/NIR solar spectrum, electron plasma fluxes, and temperature. The UV/VIS/NIR solar spectrum is simulated using an external, normally incidence and collimated class AAA Solar Simulator source, with standard Air Mass Zero (AM0) filters to shape the incident radiation spectrum. This Xe arc discharge tube source …

Simulation, Kriging, And Visualization Of Circular-Spatial Data, William James Morphet

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The circular dataimage is defined by displaying direction as the color at the same direction in a color wheel composed of a sequence of two-color gradients with color continuity between gradients. The resulting image of circular-spatial data is continuous with high resolution. Examples include ocean wind direction, Earth's main magnetic field, and rocket nozzle internal combustion flow. The cosineogram is defined as the mean cosine of the angle between random components of direction as a function of distance between observation locations. It expresses the spatial correlation of circular-spatial data. A circular kriging solution is developed based on a model fitted …

Task Scheduling And Simulation, Martin Lee Mayne

Undergraduate Honors Capstone Projects

Scheduling is a problem that is not only common computer science, but which also comes up in a variety of real world situations. Whether multi-threading computer processes, scheduling airport traffic, optimizing assembly line production and manufacturing, or ensuring that enough employees are on the floor at a given time, scheduling is important for increasing efficiency, reducing costs, optimizing production, and meeting deadlines. Scheduling has been used throughout history and has increased in efficacy through the years. Modem computerized scheduling techniques are typically much better than human calculations and often produce surprising insights and results which would have been otherwise passed …

Simulation Study Of Estimation And Inference In Factor Analysis: Normal And Non-Normal Noise Distributions, Ping Zhang

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

Objective: To study the estimation and inference m factor analyses when the data have normal or non-normal noise distributions.

Methods: Population data were created in package R with a specified number of factors, factor structure and observable variables with known loadings. Then, repeated simple random samples (SRS's) were taken from the population, independently. The maximum likelihood method with varimax rotation was used to perform factor analysis and inference on each sampled dataset. Factor loadings were estimated to determine if the estimation of the loadings was (approximately) unbiased and/or efficient for each specified population and chi-square x2-statistics were obtained to test …

Computer Simulation And Homogenization In Heating Design Optimization, Daniel K. Balls

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

The ability to ensure uniformity of temperature within a given finite physical region is an essential element in the success of many scientific processes, especially those that involve extreme fluctuation in temperature. Such a process is performed in an instrument called the LightTyper developed by Idaho Technology, Inc. of Salt Lake City Utah. This paper details the development and results of a scheme intended to obtain a heating design that ensures a high degree of temperature uniformity within the Idaho Technology instrument. Due to the experiments performed during this project, we were able to answer many questions that concerned finding …

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 …

Simulation Of The Prereversalenhancement In The Low Latitude Vertical Drifts, C. G. Fesen, R. G. Noble, A. D. Richmond, G. Crowley, Bela G. Fejer

Bela G. Fejer

Low latitude F region ion motions exhibit strong seasonal and solar cycle dependences. The pre-reversal enhancement (PRE) in the vertical ion drifts is a particularly well-known low latitude electrodynamic feature, exhibited as a sharp upward spike in the velocity shortly after local sunset, which remains poorly understood theoretically. The PRE has been successfully simulated for the first time by a general circulation model, the National Center for Atmospheric Research thermosphere/ionosphere/electrodynamic general circulation model (TIEGCM). The TIEGCM reproduces the zonal and vertical plasma drifts for equinox, June, and December for low, medium, and high solar activity. The crucial parameter in the …

A Monte Carlo Simulation Of Coulomb Collisions And Wave-Particle Interactions In Space Plasma At High Latitudes, Imad Ahmad Barghouthi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four studies were considered to simulate the ion behavior in the auroral region and the polar wind.

In study I, a Monte Carlo simulation was used to investigate the behavior of O⁺ ions that are E x B-drifting through a background of neutral O, with the effect of O⁺(Coulomb) self-collisions included. Wide ranges of the ion-to-neutral density ratio n_i / n_n and electrostatic field E were considered in order to investigate the change of ion behavior with respect to the solar cycle and altitude. For low altitudes and/or solar minimum (n_i / …

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 …

Mtclim: A Mountain Microclimate Simulation Model, United States Department Of Agriculture, Forest Service

Forestry

A model for calculating daily microclimate conditions in mountainous terrain is presented. Daily air temperature, shortwave radiation, relative humidity, and precipitation are extrapolated from data measured at National Weather Service stations. The model equations are given and the paper describes how to execute the model. Model outputs are compared with observed date from several mountain sites.

Monte Carlo Simulation Of The Game Of Twenty-One, Douglas E. Loer

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

The purpose of this paper is to demonstrate the application of computer simulation to the game of Twenty-One to predict a player's expected return from the game. Twenty-One has traditionally been one of the most popular casino games and has attracted much effort to accurately estimate the house's true advantage. Probability theory has been tried, but the thousands of different combinations of cards possible in all hands throughout the entire pack make it practically impossible to apply probability theory without overlooking some possibilities. For this reason, Twenty-One is a perfect candidate for simulation. By blocking several simulations, normal theory can …

A Microsystem Sediment-Water Simulation Study For The Proposed Jordanelle Reservoir, Heber City, Utah, United States Department Of The Interior, Bureau Of Reclamation

Water

The technique of microsystem sediment-water simulation was used to predict water quality data for the proposed Jordanelle Reservoir, Heber City, Utah. Simulation microsystems were prepared for four sites located in the north arm of the reservoir basin including two sites located in an abandoned acid mine tailings pond. Data obtained from the tailings pond microsystems indicated that low pH water and high trace metal concentrations will exist in the north arm of the reservoir. These data suggested that some kind of membrane or compacted earth lining will be necessary to seal and contain the mine spoilage. Other sites in the …

Development And Preliminary Application Of Mathematical Models To The Weber Basin, W. J. Grenney, D. S. Bowles, M. D. Chambers, J. P. Riley

Reports

The adoption of stream standards, whether for direct application or for the establishment of realistic effluent standards, creates a need to predict the impact of pollution loads on river water quality during critical flow periods or as the result of future user demands. Because of the complexity of aquatic systems, mathematical models are an excellent medium for bringing together the state-of-the-art knowledge from a variety of disciplines into a form which can be readily applied to practical problems. Applying a mathematical model to a river system has the added advantage of providing a structure for the systematic consideration of the …

Mathematical Simulation Of Temperatures In Deep Impoundments: Verification Tests Of The Water Resources Engineers, Inc. Model - Horsetooth And Flaming Gorge Reservoirs, Engineering And Research Center, Bureau Of Reclamation

All U.S. Government Documents (Utah Regional Depository)

Successful use of predictive mathematical models requires verification of the accuracy of the models by applying them to existing situations where the prediction can be compared with reality. A Corps of Engineers' modification of a deep reservoir thermal stratification model developed by Water Resources Engineers, Inc., was applied to two existing Bureau of Reclamation reservoirs for verification. Diffusion coefficients used for the Corps' Detroit Reservoir were found to apply to Horsetooth Reservoir in Colorado, for which very good computer input data were available. The Detroit diffusion coefficients gave a reasonable simulation of Flaming Gorge Reservoir in Wyoming and Utah, which …

The Practical Solutions And Computer Program Of Two Statistical Problems In Simulation, Yee Fong

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

In the last several years monte-carlo simulation has become a major tool for the analysis of complex queuing systems which are no readily amenable to analysis by conventional mathematical methods. By a complex queueing system is mean a system composed of, physically or by analogy, a network of stations or servers with traffic units moving through all or some of the servers, into the system and out or around within the system. A traffic unit desiring service by a server may either have to enter a queue first or may be served immediately. Such systems have been simulated often with …

A Logistic System Simulation Model Encompassing Poisson Processes And Normal Or Weibull Life, Willard A. Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis describes a computer simulation model for determining effective spares stock levels for recoverable items at Air Force bases and depots. The simulation model is based on the following fundamental inventory theory; whenever a demand arises, it is satisfied from stock on hand, and the quantity equal to that demand is recorded immediately; when a demand exceeds stock on hand, the excess demand is backordered immediately and when item life expires procurement action is initiated at depot level. The resulting product of the model cam be used as a guide for the optimum distribution of available spares or as …