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 …

Juxtaposition At 45 Km Of Temperatures From Rayleigh-Scatter Lidar And Reanalysis Models, David K. Moser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Weather and climate forecasts are almost exclusively produced by computer models, which use atmospheric measurements as starting points. It is a well-known and joked-about fact that model predictions can be incorrect at times. One of the reasons this happens is due to gaps in our knowledge of atmospheric conditions in areas where measurements don’t often taken place, such as the mesosphere, which stretches from roughly 45-90 km altitude.

A lidar is a device that can shoot out short bursts of laser light to measure things such as atmospheric thickness at a distance. From this information one can then derive the …

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 …

To What Extent Might Beaver Dam Building Buffer Water Storage Losses Associated With A Declining Snowpack?, Konrad Hafen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dams built by North American Beaver create natural water storage and slow water as it moves through streams. In portions of streams with beaver dams, these effects have been observed to decrease the peak magnitude of floods and increase base flow during annual summer droughts. In the western United States changes to streamflow patterns have been observed in recent decades with large spring floods coming earlier in the year, causing annual summer droughts to start earlier and last longer. These changes are linked to decreasing snowpack which acts as the most significant natural water storage reservoir by holding onto precipitation …

Lifetime Modeling Of Deficient Bridges In New York, Levi Phippen

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

Given the importance of bridges to a state's economy and strength, and the costs involved in building and maintaining bridges, maximizing their service life is essential. In order to safely extend a bridge's utility as long as possible, an understanding of its lifetime processes is needed. This paper attempts to model the lifetime of a bridge in New York once it has become deficient. Lifetime is defined to be the length of time between deficiency classification and failure. A bridge is considered deficient when certain structural components receive a poor rating in the National Bridge Inventory, which is compiled annually …

Unified Model Of Charge Transport In Insulating Polymeric Materials, Alec Sim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Charge transport, charging, and subsequent electrostatic discharge due to interactions with the space environment are primary concerns of spacecraft designers. Developing a physical understanding of the interactions of charge with the multitude of materials that spacecraft are composed of is a critical step in understanding and mitigating both short-term and long-term spacecraft degradation. In particular, the study of charge transport in highly insulating materials is critical as they store charge longer, with higher capacity, and with greater destructive capability than other materials.

The Utah State University Materials Physics Group, with the funding of the NASA James Webb Space Telescope project …

A Novel Authentication And Validation Mechanism For Analyzing Syslogs Forensically, Steena D.S. Monteiro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research proposes a novel technique for authenticating and validating syslogs for forensic analysis. This technique uses a modification of the Needham Schroeder protocol, which uses nonces (numbers used only once) and public keys. Syslogs, which were developed from an event-logging perspective and not from an evidence-sustaining one, are system treasure maps that chart out and pinpoint attacks and attack attempts. Over the past few years, research on securing syslogs has yielded enhanced syslog protocols that focus on tamper prevention and detection. However, many of these protocols, though efficient from a security perspective, are inadequate when forensics comes into play. …

A Test For Determining An Appropriate Model For Accelerated Life Data, Yuan-Who Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis was to evaluate a method for testing the appropriateness of accelerated life model. This method is based upon a polynomial approximation. The parameters are estimated and used for testing the appropriateness of the model.

An example illustrates the polynomial method. Real data are applied for this method. Comparison with another method demonstrates that the polynomial method is much simpler and has comparable accuracy.

Data Analysis Using Experimental Design Model Factorial Analysis Of Variance/Covariance (Dmaovc.Bas), Wesley E. Newton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

DMAOVC.BAS is a computer program written in the compiler version of microsoft basic which performs factorial analysis of variance/covariance with expected mean squares. The program accommodates factorial and other hierarchical experimental designs with balanced sets of data. The program is writ ten for use on most modest sized microprocessors, in which the compiler is available. The program is parameter file driven where the parameter file consists of the response variable structure, the experimental design model expressed in a similar structure as seen in most textbooks, information concerning the factors (i.e. fixed or random, and the number of levels), and necessary …

The Evaluation Of A Computer Model To Predict The Effects Of Salinity On Crop Growth, James K. Wolf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A model was developed to predict the effects of soil salinity on crop growth. The model makes three major assumptions: 1) Relative yield for a growing season is directly related to the ratio of actual and potential transpiration. 2) Water uptake by plants is in response to the water potential gradient between the plant roots and the surrounding soil. 3) The effects of the soil salinity on crop growth is solely due to the affect of osmotic potential in decreasing the water potential. Minor assumptions also included are concerned with the plant growth cover, plant root growth, and the separation …

A Model For Designing Surface Drainage Systems In Nearly Level Agricultural Lands, Rafael Maria Rojas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The increasing demand for reclamation of periodically waterlogged nearly level agricultural lands in humid tropical areas and the hazard of soil deterioration and soil moisture balance disturbances by current land forming methods suggests the need for investigations of new surface drainage design procedures. This report presents a rainfall-runoff model for simulating hydrographs from ungaged agricultural plots. The model is based on routing procedures and utilizes common soil and hydrologic data. Tests made with several small agricultural water-sheds indicate that the model could be a useful tool in simulating surface drainage design.

Input data for the model consists of (a) rainfall …

A Model To Predict The Effect Of Salinity On Crop Growth, Stuart W. Childs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A model is developed to predict the effects of soil salinity on crop growth. As an outgrowth and extension of the modelling efforts of Nimah and Hanks (1973a) and Gupta (1972), this model makes these principal assumptions in order to arrive at a quantitative relationship: 1) relative yield for a growing season is directly related to the ratio of actual and potential transpiration. 2) Water uptake by plants is in response to the water potential gradient between the plant at the soil surface and the soil surrounding the plant roots. 3) the effect of salinity on crop growth is solely …

A Relativistic One Pion Exchange Model Of Proton-Neutron Electron-Positron Pair Production, William A. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Proton-neutron electron-positron pair production cross sections are calculated in the framework of the pseudoscalar one-pion exchange model in a fully relativistic manner.

A computer program has been developed to evaluate invariants and Dirac traces for a given data point.

The sections for symmetric coplanar events for laboratory kinetic energies of 10 to 250 MeV were calculated for pair angles of 20° to 120°.

Frequency distributions were also calculated, at a laboratory energy of 200 MeV, using a random number generator to select data points. The frequency distributions are illustrated by curves.

It was noted that the inclusion of heavier bosons …

Model For Predicting Simultaneous Distribution Of Salt And Water In Soils, Satish C. Gupta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of water and salt movement in soils is necessary for development of a management scheme for controlling the quality of irrigation return flow. A computer model was developed to predict the distribution of water and salts in the root zone under varying initial and boundary conditions. The model consists of water flow and salt flow sub-models. The water flow sub-model considers the numerical approximation of the general water flow equation with modification for water loss by evapotranspiration (and thus root extraction). The salt flow sub-model considers the mass flow of salts, chemical exchange, precipitation or dissolution of CaCO_{3 …}

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 …