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This thesis outlines the development of a vector retrieval technique, based on data assimilation, for a coherent Doppler LIDAR (Light Detection and Ranging). A detailed analysis of the Optimal Interpolation (OI) technique for vector retrieval is presented. Through several modifications to the OI technique, it is shown that the modified

This thesis outlines the development of a vector retrieval technique, based on data assimilation, for a coherent Doppler LIDAR (Light Detection and Ranging). A detailed analysis of the Optimal Interpolation (OI) technique for vector retrieval is presented. Through several modifications to the OI technique, it is shown that the modified technique results in significant improvement in velocity retrieval accuracy. These modifications include changes to innovation covariance portioning, covariance binning, and analysis increment calculation. It is observed that the modified technique is able to make retrievals with better accuracy, preserves local information better, and compares well with tower measurements. In order to study the error of representativeness and vector retrieval error, a lidar simulator was constructed. Using the lidar simulator a thorough sensitivity analysis of the lidar measurement process and vector retrieval is carried out. The error of representativeness as a function of scales of motion and sensitivity of vector retrieval to look angle is quantified. Using the modified OI technique, study of nocturnal flow in Owens' Valley, CA was carried out to identify and understand uncharacteristic events on the night of March 27th 2006. Observations from 1030 UTC to 1230 UTC (0230 hr local time to 0430 hr local time) on March 27 2006 are presented. Lidar observations show complex and uncharacteristic flows such as sudden bursts of westerly cross-valley wind mixing with the dominant up-valley wind. Model results from Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®) and other in-situ instrumentations are used to corroborate and complement these observations. The modified OI technique is used to identify uncharacteristic and extreme flow events at a wind development site. Estimates of turbulence and shear from this technique are compared to tower measurements. A formulation for equivalent wind speed in the presence of variations in wind speed and direction, combined with shear is developed and used to determine wind energy content in presence of turbulence.
ContributorsChoukulkar, Aditya (Author) / Calhoun, Ronald (Thesis advisor) / Mahalov, Alex (Committee member) / Kostelich, Eric (Committee member) / Huang, Huei-Ping (Committee member) / Phelan, Patrick (Committee member) / Arizona State University (Publisher)
Created2013
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Description
A general continuum model for simulating the flow of ions in the salt baths that surround and fill excitable neurons is developed and presented. The ion densities and electric potential are computed using the drift-diffusion equations. In addition, a detailed model is given for handling the electrical dynamics on interior

A general continuum model for simulating the flow of ions in the salt baths that surround and fill excitable neurons is developed and presented. The ion densities and electric potential are computed using the drift-diffusion equations. In addition, a detailed model is given for handling the electrical dynamics on interior membrane boundaries, including a model for ion channels in the membranes that facilitate the transfer of ions in and out of cells. The model is applied to the triad synapse found in the outer plexiform layer of the retina in most species. Experimental evidence suggests the existence of a negative feedback pathway between horizontal cells and cone photoreceptors that modulates the flow of calcium ions into the synaptic terminals of cones. However, the underlying mechanism for this feedback is controversial and there are currently three competing hypotheses: the ephaptic hypothesis, the pH hypothesis and the GABA hypothesis. The goal of this work is to test some features of the ephaptic hypothesis using detailed simulations that employ rigorous numerical methods. The model is first applied in a simple rectangular geometry to demonstrate the effects of feedback for different extracellular gap widths. The model is then applied to a more complex and realistic geometry to demonstrate the existence of strictly electrical feedback, as predicted by the ephaptic hypothesis. Lastly, the effects of electrical feedback in regards to the behavior of the bipolar cell membrane potential is explored. Figures for the ion densities and electric potential are presented to verify key features of the model. The computed steady state IV curves for several cases are presented, which can be compared to experimental data. The results provide convincing evidence in favor of the ephaptic hypothesis since the existence of feedback that is strictly electrical in nature is shown, without any dependence on pH effects or chemical transmitters.
ContributorsJones, Jeremiah (Author) / Gardner, Carl (Committee member) / Baer, Steven (Committee member) / Crook, Sharon (Committee member) / Kostelich, Eric (Committee member) / Ringhofer, Christian (Committee member) / Arizona State University (Publisher)
Created2013
Description
It is possible in a properly controlled environment, such as industrial metrology, to make significant headway into the non-industrial constraints on image-based position measurement using the techniques of image registration and achieve repeatable feature measurements on the order of 0.3% of a pixel, or about an order of magnitude improvement

It is possible in a properly controlled environment, such as industrial metrology, to make significant headway into the non-industrial constraints on image-based position measurement using the techniques of image registration and achieve repeatable feature measurements on the order of 0.3% of a pixel, or about an order of magnitude improvement on conventional real-world performance. These measurements are then used as inputs for a model optimal, model agnostic, smoothing for calibration of a laser scribe and online tracking of velocimeter using video input. Using appropriate smooth interpolation to increase effective sample density can reduce uncertainty and improve estimates. Use of the proper negative offset of the template function has the result of creating a convolution with higher local curvature than either template of target function which allows improved center-finding. Using the Akaike Information Criterion with a smoothing spline function it is possible to perform a model-optimal smooth on scalar measurements without knowing the underlying model and to determine the function describing the uncertainty in that optimal smooth. An example of empiric derivation of the parameters for a rudimentary Kalman Filter from this is then provided, and tested. Using the techniques of Exploratory Data Analysis and the "Formulize" genetic algorithm tool to convert the spline models into more accessible analytic forms resulted in stable, properly generalized, KF with performance and simplicity that exceeds "textbook" implementations thereof. Validation of the measurement includes that, in analytic case, it led to arbitrary precision in measurement of feature; in reasonable test case using the methods proposed, a reasonable and consistent maximum error of around 0.3% the length of a pixel was achieved and in practice using pixels that were 700nm in size feature position was located to within ± 2 nm. Robust applicability is demonstrated by the measurement of indicator position for a King model 2-32-G-042 rotameter.
ContributorsMunroe, Michael R (Author) / Phelan, Patrick (Thesis advisor) / Kostelich, Eric (Committee member) / Mahalov, Alex (Committee member) / Arizona State University (Publisher)
Created2012
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This study was conducted to determine the difference in compressive strength between decayed and healthy teeth. The teeth were subjected to a compressive force to simulate the process of mastication. This was done to show that healthy teeth would be better at handling these compressive forces since they have more

This study was conducted to determine the difference in compressive strength between decayed and healthy teeth. The teeth were subjected to a compressive force to simulate the process of mastication. This was done to show that healthy teeth would be better at handling these compressive forces since they have more enamel. 26 teeth samples were collected (19 molars, 4 canines, and 3 premolars) evenly distributed between healthy and decayed. The samples were dimensionally analyzed using electronic calipers and then categorized as either decayed or healthy. The samples were then placed in a nut bolt with epoxy so that the samples could be compressed. Each sample was recorded on video while they were being exposed to the compressive force. This was done to observe how the samples were coming in contact with the Shimadzu compression machine. The amount of force that was required for the samples to exhibit the first point of breakage was recorded by the machine in pounds of force. Various analyses were conducted to determine relationships between several variables. The results showed that as the total and occlusal surface area increased, so did the amount of force the samples could absorb before breakage. As the machine came in contact with more cusps among the molar samples, those samples were able to absorb a larger compressive force. The average force that the decayed and healthy molar samples endured before breakage was roughly even, with the decayed samples average being slightly greater.

ContributorsHenscheid, Keaton J (Author) / Quaranta, Kimberly (Thesis director) / Peoples, Samuel (Committee member) / College of Health Solutions (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

This study examines the effectiveness of two modes of exercise on inhibitory control in adults with Down Syndrome (DS). Thirteen participants attended four sessions: a baseline assessment, an Assisted Cycling Therapy (ACT) session, a Resistance Training (RT) session, and a session of No Training (NT). In the baseline assessment, 1-repetition

This study examines the effectiveness of two modes of exercise on inhibitory control in adults with Down Syndrome (DS). Thirteen participants attended four sessions: a baseline assessment, an Assisted Cycling Therapy (ACT) session, a Resistance Training (RT) session, and a session of No Training (NT). In the baseline assessment, 1-repetition max (1RM) measurements and voluntary pedal rate measurements were taken. In the resistance training session, the leg press, chest press, seated row, leg curl, shoulder press, and latissimus pulldown were performed. In the cycling intervention, the participant completed 30 minutes of cycling. The Erikson Flanker task was administered prior to each session (i.e., pretest) and after the intervention (i.e., post-test). The results were somewhat consistent with the hypothesis that inhibition time improved more following RT and ACT than NT. there was also a significant difference between ACT and NT. Additionally, it was hypothesized that all measures would improve following each acute exercise intervention, but the most significant improvements were seen following ACT. In conclusion, an acute session of ACT demonstrated a significant trend towards improvements in inhibitory control in adults with DS which we interpreted using a model of neural changes.

ContributorsHayes, Claire (Author) / Ringenbach, Shannon (Thesis director) / Arnold, Nate (Committee member) / Rand, Miya (Committee member) / Edson College of Nursing and Health Innovation (Contributor) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The various health benefits of vinegar ingestion have been studied extensively in the<br/>literature. Moreover, emerging research suggests vinegar may also have an effect on mental<br/>health. Beneficial effects of certain diets on mood have been reported, however, the mechanisms<br/>are unknown. The current study aimed to determine if vinegar ingestion positively affects

The various health benefits of vinegar ingestion have been studied extensively in the<br/>literature. Moreover, emerging research suggests vinegar may also have an effect on mental<br/>health. Beneficial effects of certain diets on mood have been reported, however, the mechanisms<br/>are unknown. The current study aimed to determine if vinegar ingestion positively affects mood<br/>state in healthy young adults. This was a randomized, single blinded controlled trial consisting of<br/>25 subjects. Participants were randomly assigned to either the vinegar group (consumed 2<br/>tablespoons of liquid vinegar diluted in one cup water twice daily with meals) or the control<br/>group (consumed one vinegar pill daily with a meal), and the intervention lasted 4 weeks.<br/>Subjects completed mood questionnaires pre- and post-intervention. Results showed a significant<br/>improvement in CES-D and POMS-Depression scores for the vinegar group compared to the<br/>control. This study suggests that vinegar ingestion may improve depressive symptoms in healthy<br/>young adults.

ContributorsWilliams, Susanna (Author) / Johnston, Carol (Thesis director) / Whisner, Corrie (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description
Mortality of 1918 influenza virus was high, partly due to bacteria coinfections. We characterize pandemic mortality in Arizona, which had high prevalence of tuberculosis. We applied regressions to over 35,000 data points to estimate the basic reproduction number and excess mortality. Age-specific mortality curves show elevated mortality for all age

Mortality of 1918 influenza virus was high, partly due to bacteria coinfections. We characterize pandemic mortality in Arizona, which had high prevalence of tuberculosis. We applied regressions to over 35,000 data points to estimate the basic reproduction number and excess mortality. Age-specific mortality curves show elevated mortality for all age groups, especially the young, and senior sparing effects. The low value for reproduction number indicates that transmissibility was moderately low.
ContributorsJenner, Melinda Eva (Author) / Chowell-Puente, Gerardo (Thesis director) / Kostelich, Eric (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-05
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Description
Glioblastoma Multiforme (GBM) is an aggressive and deadly form of brain cancer with a median survival time of about a year with treatment. Due to the aggressive nature of these tumors and the tendency of gliomas to follow white matter tracks in the brain, each tumor mass has a unique

Glioblastoma Multiforme (GBM) is an aggressive and deadly form of brain cancer with a median survival time of about a year with treatment. Due to the aggressive nature of these tumors and the tendency of gliomas to follow white matter tracks in the brain, each tumor mass has a unique growth pattern. Consequently it is difficult for neurosurgeons to anticipate where the tumor will spread in the brain, making treatment planning difficult. Archival patient data including MRI scans depicting the progress of tumors have been helpful in developing a model to predict Glioblastoma proliferation, but limited scans per patient make the tumor growth rate difficult to determine. Furthermore, patient treatment between scan points can significantly compound the challenge of accurately predicting the tumor growth. A partnership with Barrow Neurological Institute has allowed murine studies to be conducted in order to closely observe tumor growth and potentially improve the current model to more closely resemble intermittent stages of GBM growth without treatment effects.
ContributorsSnyder, Lena Haley (Author) / Kostelich, Eric (Thesis director) / Frakes, David (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
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Dividing the plane in half leaves every border point of one region a border point of both regions. Can we divide up the plane into three or more regions such that any point on the boundary of at least one region is on the border of all the regions? In

Dividing the plane in half leaves every border point of one region a border point of both regions. Can we divide up the plane into three or more regions such that any point on the boundary of at least one region is on the border of all the regions? In fact, it is possible to design a dynamical system for which the basins of attractions have this Wada property. In certain circumstances, both the Hénon map, a simple system, and the forced damped pendulum, a physical model, produce Wada basins.
ContributorsWhitehurst, Ryan David (Author) / Kostelich, Eric (Thesis director) / Jones, Donald (Committee member) / Armbruster, Dieter (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2013-05
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Childhood obesity is a growing public health concern in the United States. For several years, many interventions have been established to reduce the prevalence of childhood obesity. However, these interventions have not adequately utilized existing models of behavior change, and as a result, have been unsuccessful in increasing levels of

Childhood obesity is a growing public health concern in the United States. For several years, many interventions have been established to reduce the prevalence of childhood obesity. However, these interventions have not adequately utilized existing models of behavior change, and as a result, have been unsuccessful in increasing levels of physical activity and healthy dietary intake. One such model of change, the Transtheoretical Model, views behavior change as occurring through a series of stages with progression through the stages being facilitated by cognitive and behavioral processes. Within these processes the constructs of consciousness-raising, helping relationships, and self-efficacy have been shown to be most influential in changing behaviors. Thus, the objective of this paper is to evaluate the effectiveness of such constructs and establish a multi-faceted approach to combat this epidemic.
ContributorsWang, Janice (Author) / Broman, Tannah (Thesis director) / Hoffner, Kristin (Committee member) / Baldwin, Marjorie (Committee member) / Barrett, The Honors College (Contributor) / College of Health Solutions (Contributor)
Created2012-12