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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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The Effect Of Direct Instruction In Teaching Addition And Subtraction Of Decimals And Decimal Word Problems On Students At Risk For Academic Failure, Heather Hoopes Small May 2011

The Effect Of Direct Instruction In Teaching Addition And Subtraction Of Decimals And Decimal Word Problems On Students At Risk For Academic Failure, Heather Hoopes Small

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the effects of a direct instruction program on the ability of elementary school students identified as at risk for math failure to add and subtract numbers with decimals, and complete addition and subtraction word problems with decimals. Direct instruction has previously been shown to increase the math skills of special education and general education students. This study examined the extent to which these students could master these skills in six hours of instruction, with carefully designed sequences of examples and strategy instruction in word problems. The study took place in two elementary schools. The participants were fifth …


Ligand And Metal Effects On The Co-Release Reactivity Of Metal Acireductone And Flavonolate Complexes, Katarzyna Grubel May 2011

Ligand And Metal Effects On The Co-Release Reactivity Of Metal Acireductone And Flavonolate Complexes, Katarzyna Grubel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research reported herein involves synthetic metal complexes of relevance to dioxygenase enzymes (Ni(II)-containing acireductone dioxygenase (Ni(II)-ARD) and quercentinase (2,4-flavonol dioxygenase) that promote oxidative carbon-carbon bond cleavage and CO release. The experiments focus on the elucidation of structure-reactivity relationships and evaluation of the conditions under which CO is generated.

It had been proposed that hydrogen bond donors in the secondary environment of the active site metal center in Ni(II)-ARD influence the coordination of the acireductone substrate on the nickel center. To evaluate this proposal, we investigated the Ni(II) coordination chemistry of an acireductone-type enolate anion using a supporting chelate ligand …


Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch May 2011

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …


Pond-Hindsight: Applying Hindsight Optimization To Partially-Observable Markov Decision Processes, Alan Olsen May 2011

Pond-Hindsight: Applying Hindsight Optimization To Partially-Observable Markov Decision Processes, Alan Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Partially-observable Markov decision processes (POMDPs) are especially good at modeling real-world problems because they allow for sensor and effector uncertainty. Unfortunately, such uncertainty makes solving a POMDP computationally challenging. Traditional approaches, which are based on value iteration, can be slow because they find optimal actions for every possible situation. With the help of the Fast Forward (FF) planner, FF- Replan and FF-Hindsight have shown success in quickly solving fully-observable Markov decision processes (MDPs) by solving classical planning translations of the problem. This thesis extends the concept of problem determination to POMDPs by sampling action observations (similar to how FF-Replan samples …


Factors Affecting Greater Sage-Grouse (Centrocercus Urophasianus) Survival And Movement In South-Central Utah, Danny Caudill May 2011

Factors Affecting Greater Sage-Grouse (Centrocercus Urophasianus) Survival And Movement In South-Central Utah, Danny Caudill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse are the largest North American grouse species and are dependent on sagebrush for survival. Sage-grouse populations have declined throughout the west. Habitat fragmentation and degradation are likely the main causes of declining populations, and concern has lead to the petitioning for the sage-grouse to be listed under the Endangered Species Act. Survival of adult and juvenile sage-grouse is thought to be limiting population growth. However, survival of juvenile sage-grouse is poorly understood. I aimed to improve the knowledge gap regarding juvenile sage-grouse survival. With improved knowledge of juvenile survival, management actions can be employed to benefit sage-grouse populations. …


Investigation Of The Design And Static Behavior Of Cylindrical Tubular Composite Adhesive Joints Utilizing The Finite Element Method And Stress-Based Failure Theories, Michael D. Lambert May 2011

Investigation Of The Design And Static Behavior Of Cylindrical Tubular Composite Adhesive Joints Utilizing The Finite Element Method And Stress-Based Failure Theories, Michael D. Lambert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The stress and strength behavior of cylindrical tubular adhesive joints composed of dissimilar materials was explored. This was accomplished with the finite element method (FEM) and stress-based failure theories. Also, it was shown how a design of experiments (DOE) based method can be used to objectively organize the process of optimizing joint strength by using stress-based failure criteria.

The finite element program used in this work was written in-house from scratch to implement the FEM for the purpose of solving both axisymmetric and three-dimensional linear elastic governing equations of static equilibrium. The formulation of the three-dimensional model is presented, and …


Making The “Good” Professor: Does Graduate Mentoring Promote Gender Equality In Academia?, Anita Harker Armstrong May 2011

Making The “Good” Professor: Does Graduate Mentoring Promote Gender Equality In Academia?, Anita Harker Armstrong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mentorship is a critical component of a graduate education and facilitates the process of socialization into the role of professorship. Numerous studies continue to support the idea that mentorship, particularly woman-to-woman mentoring, is essential for overcoming barriers to women’s mobility within male-dominated fields. This study critically examines this assumption through the analysis of 59 qualitative interviews with faculty mentors and graduate students in science, technology, engineering, and mathematics conducted at one Canadian and one American institution. Initially, I explore how mothers in academe are socialized from differing levels to fit into narrowly defined roles as “good” professors. This expands our …


The Effect Of Stream Restoration On Preferred Cutthroat Trout Habitat In The Strawberry River, Utah, Nicolas R. Braithwaite May 2011

The Effect Of Stream Restoration On Preferred Cutthroat Trout Habitat In The Strawberry River, Utah, Nicolas R. Braithwaite

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stream restoration has become a popular management tool for attempting to increase and/or restore fish populations by improving habitat. A section of the Strawberry River, Utah recently underwent a stream restoration project, where the main goals of the project included increasing spawning activity, rearing potential, and resident populations of Bear Lake cutthroat trout Oncorhynchus clarkia utah. The impact of the restoration project on cutthroat trout was investigated by first characterizing preferred habitat for different life stages, investigating habitat as a limiting factor in the system, and then assessing the quality of available habitat by comparing restored/unrestored sections of stream …


Use Of Extrusion Technology And Fat Replacers To Produce High Protein, Low Fat Cheese, Amrita Dubey May 2011

Use Of Extrusion Technology And Fat Replacers To Produce High Protein, Low Fat Cheese, Amrita Dubey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the use of extrusion technology and fat replacers to produce high protein, low fat Cheddar cheese. In chapter 3, four different fat replacers were tested at the highest concentration level of each, as recommended by the manufacturers for low fat cheese, to investigate the change in cheese texture and optimize extruder conditions. In addition, the press time/pressure combinations of the extruded cheeses were optimized. The fat replacers and extruder conditions that were effective in improving the texture of low fat cheese were then used in chapter 4.

In chapter 4, three fat replacers were used at three …


Invertebrate Community Changes Along Coqui Invasion Fronts In Hawaii, Ryan T. Choi May 2011

Invertebrate Community Changes Along Coqui Invasion Fronts In Hawaii, Ryan T. Choi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Puerto Rican coqui frog, Eleutherodactylus coqui, was introduced to Hawaii in the late 1980s via the commercial horticulture trade. Previous research has shown that coquis can change invertebrate communities, but these studies were conducted at small scales using controlled, manipulative experiments. The objective of this research was to determine whether coqui invasions change invertebrate communities at the landscape scale across the island of Hawaii. At each invasion front, we measured environmental variability on either side of the front and removed sites that were too variable across the front to ensure that the impacts we measured were the result …


Improving The Quality Of Teacher Support In Anticipation Of The Instructional Use Of Technology: An Action Research Study, Darren E. Draper May 2011

Improving The Quality Of Teacher Support In Anticipation Of The Instructional Use Of Technology: An Action Research Study, Darren E. Draper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The formation of the Canyons School District brought with it unique opportunities for assessing current practice, implementing change, and evaluating the effectiveness of that change. Accordingly, this action research project served as an effective initial step in accomplishing this series of tasks. The purpose of this mixed methods study was to describe the instructional technology needs of teachers, as well as the related support efforts provided in a public school district.

Data gathering methods included a district-wide needs assessment survey of school-based licensed personnel (N =1,313). Additionally, the utilization of focus group protocol on an existing district technology committee …


Model-Based Stripmap Synthetic Aperture Radar Processing, Roger D. West May 2011

Model-Based Stripmap Synthetic Aperture Radar Processing, Roger D. West

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic aperture radar (SAR) is a type of remote sensor that provides its own illumination and is capable of forming high resolution images of the reflectivity of a scene. The reflectivity of the scene that is measured is dependent on the choice of carrier frequency; different carrier frequencies will yield different images of the same scene.

There are different modes for SAR sensors; two common modes are spotlight mode and stripmap mode. Furthermore, SAR sensors can either be continuously transmitting a signal, or they can transmit a pulse at some pulse repetition frequency (PRF). The work in this dissertation is …


Characteristics Of Combustion Flame Sprayed Nickel Aluminum Using A Coanda Assisted Spray Manipulation Collar For Off-Normal Deposits, Reid S. Archibald May 2011

Characteristics Of Combustion Flame Sprayed Nickel Aluminum Using A Coanda Assisted Spray Manipulation Collar For Off-Normal Deposits, Reid S. Archibald

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A novel flame spray collar called the Coanda Assisted Spray Manipulation collar (CSM) has been tested for use on the Sulzer Metco 5P II combustion flame spray gun. A comparison study of the stock nozzle and the CSM has been performed by evaluating the porosity, surface roughness, microhardness, tensile strength and microscopy of normal and off-normal sprayed NiAl deposits. The use of the CSM collar resulted in the need to position the sprayed coupons closer to the gun, which in turn affected the particle impact energy and particle temperatures of the NiAl powder. For the CSM, porosities had a larger …


The Transfer Of Agricultural Water To Municipal And Industrial Usages, Dallin Paul Stephens May 2011

The Transfer Of Agricultural Water To Municipal And Industrial Usages, Dallin Paul Stephens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The water that is available for beneficial use in Utah is quickly approaching full appropriation; water that has been claimed is nearing the amount that is available for use. The Division of Water Resources of the State of Utah has organized a three-part plan to "Plan, Conserve, Develop and Protect Utah's Water Resources." One of these three elements has a focus to "provide comprehensive water planning." Such planning is best achieved when current and accurate data on the uses of the state's water are available.

The primary purpose of this thesis was to provide an evaluation, from data collected on …


Characterizing High School Students' Systems Thinking In Engineering Design Through The Function-Behavior-Structure (Fbs) Framework, Matthew D. Lammi May 2011

Characterizing High School Students' Systems Thinking In Engineering Design Through The Function-Behavior-Structure (Fbs) Framework, Matthew D. Lammi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The aim of this research study was to examine high school students‟ systems thinking when engaged in an engineering design challenge. This study included 12 high school students that were paired into teams of two to work through an engineering design challenge. These dyads were given one hour in their classrooms with access to a computer and engineering sketching paper to complete the design. Immediately following the design challenge, the students participated in a post hoc reflective group interview.

The methodology of this study was informed by and derived from cognitive science‟s verbal protocol analysis. Multiple forms of data were …


Exploring The Relation Between Office Discipline Referrals And Reinforcement Rates In Schoolwide Positive Behavior Support Programs, Michelle Woidneck May 2011

Exploring The Relation Between Office Discipline Referrals And Reinforcement Rates In Schoolwide Positive Behavior Support Programs, Michelle Woidneck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The implementation of schoolwide positive behavioral support (SWPBS) programs is becoming increasingly common in schools across the nation. Although a primary assumption of SWPBS is that schoolwide administration of positive supports to students who meet behavioral expectations will result in fewer behavior problems, surprisingly few studies have investigated the effects of various positive reinforcement rates (RR) on office discipline referral rates (ODR). This study investigated the relationship between RRs and ODRs among schools (N = 44) implementing SWPBS programs with high fidelity. Results revealed no significant differences in RRs or ODRs between Title I and non-Title I schools but …


Assessing The Potential For Seepage Barrier Defects To Propagate Into Seepage Erosion Mechanisms, Ryan G. Van Leuven May 2011

Assessing The Potential For Seepage Barrier Defects To Propagate Into Seepage Erosion Mechanisms, Ryan G. Van Leuven

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Seepage barriers have been used extensively to mitigate seepage problems in dams and levees. Although the design of many of these dams and levees has been based on intact barriers, seepage barriers have been shown to be susceptible to deformation and cracking when high differential hydraulic pressures act across the barrier. Under certain conditions, these cracks can lead to serious seepage problems, which could potentially lead to the development of a low-resistance seepage pathway. Three scenarios have been identified where there is the potential for erosion to occur adjacent to a crack in a barrier: 1) erosion at the interface …


Stratigraphic, Microfossil, And Geochemical Analysis Of The Neoproterozoic Uinta Mountain Group, Utah: Evidence For A Eutrophication Event?, Dawn Schmidli Hayes May 2011

Stratigraphic, Microfossil, And Geochemical Analysis Of The Neoproterozoic Uinta Mountain Group, Utah: Evidence For A Eutrophication Event?, Dawn Schmidli Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several previous Neoproterozoic microfossil diversity studies yield evidence for a relatively sudden biotic change prior to the first well‐constrained Sturtian glaciations. In an event interpreted as a mass extinction of eukaryotic phytoplankton followed by bacterial dominance, diverse assemblages of complex acritarchs are replaced by more uniform assemblages consisting of simple leiosphaerid acritarchs and bacteria. Recent data from the Chuar Group of the Grand Canyon (770‐742 Ma) suggest this biotic change was caused by eutrophication rather than the direct effects of Sturtian glaciation; evidence includes total organic carbon increases indicative of increasing primary productivity followed by iron speciation values that suggest …


Computational Efficiency Of A Hybrid Mass Concentration And Spherical Harmonic Modeling, Nathan Piepgrass May 2011

Computational Efficiency Of A Hybrid Mass Concentration And Spherical Harmonic Modeling, Nathan Piepgrass

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Through Spherical Harmonics, one can describe complex gravitational fields. However as the order and degree of the spherical harmonics increases, the computation speed rises exponentially. In addition, for onboard applications of spherical harmonics, the processors are radiation hardened in order to mitigate negative effects of the space environment on electronics. But, those processors have outdated processing speeds, resulting in a slower onboard spherical harmonic program.

This thesis examines a partial solution to the slow computation speed of spherical harmonics programs. The partial solution was to supplant the gravity models in the flight software. The spherical harmonics gravity model can be …


Piano Key Weir Head Discharge Relationships, Ricky M. Anderson May 2011

Piano Key Weir Head Discharge Relationships, Ricky M. Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A piano key (PK) weir is a type of nonlinear (labyrinth-type) weir developed specifically for free-surface flow control structures with relatively small spillway footprints. Currently, no generally accepted standard PK weir design procedure is available. This is due, in part, to the large number of geometric parameters and a limited understanding of their effects on discharge efficiency (discharge efficiency is quantified by the discharge coefficient of the standard weir equation). However, Hydrocoop, a non-profit French dam spillways association, has recommended a PK weir design and a head-discharge relationship specific to that geometry.

To develop a better understanding of the effects …


Novel Application Of Neutrosophic Logic In Classifiers Evaluated Under Region-Based Image Categorization System, Wen Ju May 2011

Novel Application Of Neutrosophic Logic In Classifiers Evaluated Under Region-Based Image Categorization System, Wen Ju

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Neutrosophic logic is a relatively new logic that is a generalization of fuzzy logic. In this dissertation, for the first time, neutrosophic logic is applied to the field of classifiers where a support vector machine (SVM) is adopted as the example to validate the feasibility and effectiveness of neutrosophic logic. The proposed neutrosophic set is integrated into a reformulated SVM, and the performance of the achieved classifier N-SVM is evaluated under an image categorization system. Image categorization is an important yet challenging research topic in computer vision. In this dissertation, images are first segmented by a hierarchical two-stage self organizing …


Automatic Particle Image Velocimetry Uncertainty Quantification, Benjamin H. Timmins May 2011

Automatic Particle Image Velocimetry Uncertainty Quantification, Benjamin H. Timmins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The uncertainty of any measurement is the interval in which one believes the actual error lies. Particle Image Velocimetry (PIV) measurement error depends on the PIV algorithm used, a wide range of user inputs, flow characteristics, and the experimental setup. Since these factors vary in time and space, they lead to nonuniform error throughout the flow field. As such, a universal PIV uncertainty estimate is not adequate and can be misleading. This is of particular interest when PIV data are used for comparison with computational or experimental data.

A method to estimate the uncertainty due to the PIV calculation of …


Comparative Studies On Scale-Up Methods Of Single-Use Bioreactors, Emily B. Stoker May 2011

Comparative Studies On Scale-Up Methods Of Single-Use Bioreactors, Emily B. Stoker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was performed to increase knowledge of oxygen mass transfer (kLa) and mixing times in the scale-up of disposable bioreactors.Results of oxygen mass transfer studies showed kLa to increase with increasing agitation and aeration rates. By maintaining a scale-up constant such as gassed power to volume or shear, an almost constant kLa was achieved during scale-up from 50 to 2000 L. Using the scale-up constant Pg/V resulted in statistically higher kLa values at greater reactor volumes. Mixing times were revealed to be significantly affected by agitation, but not by the aeration rates tested. No pattern …


Understanding Teacher Users Of A Digital Library Service: A Clustering Approach, Beijie Xu May 2011

Understanding Teacher Users Of A Digital Library Service: A Clustering Approach, Beijie Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research examined teachers' online behaviors while using a digital library service—the Instructional Architect (IA)—through three consecutive studies. In the first two studies, a statistical model called latent class analysis (LCA) was applied to cluster different groups of IA teachers according to their diverse online behaviors. The third study further examined relationships between teachers' demographic characteristics and their usage patterns. Several user clusters emerged from the LCA results of Study I. These clusters were named isolated islanders, lukewarm teachers, goal-oriented brokers, window shoppers, key brokers, beneficiaries, classroom practitioners, and dedicated sticky users. …


Essays On Population Aging And Social Security In The U.S., Shantanu Bagchi May 2011

Essays On Population Aging And Social Security In The U.S., Shantanu Bagchi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past few decades, falling birth rates and increasing life expectancies have threatened the viability of social security programs all across the Organisation for Economic Co-operation and Development (OECD). In this dissertation, I attempt to shed some light on the extent of the crisis that the social security program in the United States (U.S.) currently faces, and I also recommend one possible reform policy. In the first essay, I provide an alternative estimate of the impact of population aging on the future social security benefits in the U.S., while accounting for the household-level and macroeconomic adjustments to population aging. …


Graphshop: An Interactive Software Environment For Graph Theory Research And Applications, Aaron Andersen May 2011

Graphshop: An Interactive Software Environment For Graph Theory Research And Applications, Aaron Andersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Graph Theory is the mathematical study of the structure of abstract relationships between objects. Although these constructions (graphs) are themselves purely theoretical, their ability to model pair-wise relationships in systems of arbitrary complexity yields abundant direct correspondence with numerous important physical and societal systems in the real world. Additionally, the simple discrete nature of fundamental graph structures allows for easy pseudo-geometric visualization of graphs in a wide variety of ways. Taken together, these two properties suggest that graph theory teaching, research, and applications would benefit greatly from the use of a unified software environment for graph construction, interaction, and visualization. …


Dynamics Of Equatorial Spread F Using Ground-Based Optical And Radar Measurements, Narayan P. Chapagain May 2011

Dynamics Of Equatorial Spread F Using Ground-Based Optical And Radar Measurements, Narayan P. Chapagain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth's equatorial ionosphere most often shows the occurrence of large plasma density and velocity fluctuations with a broad range of scale sizes and amplitudes. These night time ionospheric irregularities in the F-region are commonly referred to as equatorial spread F (ESF) or plasma bubbles (EPBs). This dissertation focuses on analysis of ground-based optical and radar measurements to investigate the development and dynamics of ESF, which can significantly disrupt radio communication and GPS navigation systems. OI (630.0 nm) airglow image data were obtained by the Utah State University all-sky CCD camera, primarily during the equinox period, from three different longitudinal …


A Fully Automatic Segmentation Method For Breast Ultrasound Images, Juan Shan May 2011

A Fully Automatic Segmentation Method For Breast Ultrasound Images, Juan Shan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Breast cancer is the second leading cause of death of women worldwide. Accurate lesion boundary detection is important for breast cancer diagnosis. Since many crucial features for discriminating benign and malignant lesions are based on the contour, shape, and texture of the lesion, an accurate segmentation method is essential for a successful diagnosis. Ultrasound is an effective screening tool and primarily useful for differentiating benign and malignant lesions. However, due to inherent speckle noise and low contrast of breast ultrasound imaging, automatic lesion segmentation is still a challenging task.

This research focuses on developing a novel, effective, and fully automatic …


Individualistic Response Of Piñon And Juniper Tree Species Distributions To Climate Change In North America's Arid Interior West, Jacob R. Gibson May 2011

Individualistic Response Of Piñon And Juniper Tree Species Distributions To Climate Change In North America's Arid Interior West, Jacob R. Gibson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Piñon and juniper tree species have species-specific climatic requirements, resulting in unique distributions and differential responses to climate change. Piñons and junipers co-dominate the arid woodlands of North America as groups with widespread hybridization. Two piñons, Pinus edulis; P. monophylla, and four junipers, Juniperus deppeana var. deppeana; J. monosperma; J. occidentalis; J. osteosperma, are endemic to the midlatitude interior west and form three groups of hybridizing sister species, P. edulis-P. monophylla; J. deppeana var. deppeana-J. monosperma; J. occidentalis-J. osteosperma. Recent droughts have caused widespread mortality among piñons, but have had less impact on …


Surface Morphology Implications On Langmuir Probe Measurements, Padmashri Suresh May 2011

Surface Morphology Implications On Langmuir Probe Measurements, Padmashri Suresh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Langmuir probes are extensively employed to study the plasmas in space and laboratory environments. Successful measurements require a comprehensive modeling of both the plasma environment and the probe conditions in the form of current collection models. In this thesis, the surface morphology implications on the probe current collection are investigated. This problem is applied and solved in the context of a CubeSat regime. The first problem that is investigated is the consequence of surface structural variability on the current measurements. A new model for dealing with non-uniformity of the probe surface structure is developed in this paper. This model is …