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In Pursuit Of Comparability: Evaluating Influence And Interaction Among Components Of The Home Range Estimation Process In Chimpanzee Datasets, Jillian J. Rutherford Jul 2021

In Pursuit Of Comparability: Evaluating Influence And Interaction Among Components Of The Home Range Estimation Process In Chimpanzee Datasets, Jillian J. Rutherford

Geography ETDs

The home range (HR) is a fundamental manifestation of an animal’s spatial behavior, but its study has been limited by unclear, unreliable, and unstandardized methodological approaches for measurement. The lack of a comprehensive evaluation of the influence of components of the HR estimation process has hampered consensus over best practices for collecting and analysing movement data. This leads to wide variation in practice, thwarting direct comparability between HR estimates and curtailing the cohesive power of cross-study findings necessary for testing hypotheses and developing appropriate conservation and management strategies. In this thesis I explore the influence of and interaction between common …


Geospatial Analysis Of Potential Flooding From Storm Surge And Sea-Level Change On The Texas Coast By 2100, Gennadii Prykhodko May 2020

Geospatial Analysis Of Potential Flooding From Storm Surge And Sea-Level Change On The Texas Coast By 2100, Gennadii Prykhodko

Earth & Environmental Sciences Theses

Tropical cyclones pose a major hazard to the State of Texas. Anthropogenic climate change and global warming have the potential to increase extreme weather events and lead to enhanced flood hazard zones. This study aims to analyze potential flooding from hurricane induced storm tides in the Houston metroplex area, and particularly in Harris County. A geospatial framework is proposed for modeling inundation from storm surge with sea-level rise. Spatial models and statistics are applied to the State of Texas with the focus on the Houston metropolitan area including Harris County. Historical and observational tropical cyclone data is used to examine …


@Yourlocation: A Spatial Analysis Of Geotagged Tweets In The Us, Ocean Mckinney Jan 2019

@Yourlocation: A Spatial Analysis Of Geotagged Tweets In The Us, Ocean Mckinney

CMC Senior Theses

This project examines the spatial network properties observable from geo-located tweet data. Conventional exploration examines characteristics of a variety of network attributes, but few employ spatial edge correlations in their analysis. Recent studies have demonstrated the improvements that these correlations contribute to drawing conclusions about network structure. This thesis expands upon social network research utilizing spatial edge correlations and presents processing and formatting techniques for JSON (JavaScript Object Notation) data.


Humans As Sensors: The Influence Of Extreme Heat Vulnerability Factors On Risk Perceptions Across The Contiguous United States, Forrest Scott Schoessow Aug 2018

Humans As Sensors: The Influence Of Extreme Heat Vulnerability Factors On Risk Perceptions Across The Contiguous United States, Forrest Scott Schoessow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extreme heat events are the deadliest natural hazard in the United States and will continue to get worse in the coming years due to the effects of climate change. As a result, more people will experience deadly heat conditions. This highlights the need for decision-makers to develop better strategies for preventing future losses. How badly individuals are affected by extreme heat depends on many circumstances, such as how high temperatures actually are, weather conditions, and location. For example, a dry 90 °F day in Phoenix is probably more tolerable than a humid 90 °F day in New Orleans for most …


Spatio-Temporal Variability Of Precipitation And Drought In The State Of Arizona, Usa, Samuel Nimako Nyarkoh Jun 2018

Spatio-Temporal Variability Of Precipitation And Drought In The State Of Arizona, Usa, Samuel Nimako Nyarkoh

Masters Theses

As a result of climate change, several dry regions continue to get drier as precipitation amounts decline. This decline impact water resources and hinder economic development. Understanding the variability of precipitation and drought through climatic, agricultural and hydrological studies is therefore critical to decision makers and stakeholders in developing proactive measures that promotes economic development.

This study therefore uses dataset from 55 Meteorological stations containing 110-year (1900-2010) monthly precipitation data and a series of spatial and temporal tests to investigate the spatial and temporal patterns of precipitation and drought as well as the effects of local factors such as topography …


Spatial Patterns Of Precipitation Trends In The Continental United States, 1950-2016, Shayne O'Brien May 2018

Spatial Patterns Of Precipitation Trends In The Continental United States, 1950-2016, Shayne O'Brien

Master's Theses

Identifying trends in aspects of meteorology is becoming increasingly important to understanding how climate can be expected to change, and how those affected may plan contingencies. Analyzing spatial patterns of precipitation trends allows for associations to be discovered to better understand regional climatology. For this study, daily precipitation data were collected from The National Oceanic and Atmospheric Administration (NOAA) Global Historical Climate Network (GHCN) at stations across the continental United States, with selection based on distance from each other within a state, as well as percent completeness of observation data. Two stations per state were selected, with some exceptions for …


Development Of A High-Resolution Spatial Heterodyne Libs Spectrometer, Kevin A. Dudley Jan 2018

Development Of A High-Resolution Spatial Heterodyne Libs Spectrometer, Kevin A. Dudley

Theses and Dissertations

Laser-Induced Breakdown Spectroscopy (LIBS) is an atomic emission technique that uses a pulse laser to ablate a sample and form a plasma. Atomic emissions from the plasma provide unique elemental characteristics regarding the composition of the sample. The technique produces valuable qualitative results, but the accuracy of quantitative analyses is hindered by spectral line broadening mechanisms and laser pulse reproducibility, among other factors. The Spatial Heterodyne Spectrometer (SHS) is a high-resolution spectrometer with very high light throughput, and its use to LIBS is currently limited to two peer-reviewed publications. In the following work a high resolution SHS is developed and …


Spatial Feedback As A Mechanism To Improve Topographic Map Literacy Using The Augmented Reality Sandbox, Justin Wayne Moore Jan 2018

Spatial Feedback As A Mechanism To Improve Topographic Map Literacy Using The Augmented Reality Sandbox, Justin Wayne Moore

Graduate Research Theses & Dissertations

Topographic maps represent three-dimensional (3D) terrain using a system of two-dimensional (2D) symbols. To facilitate students’ understanding of topographic maps, the Augmented Reality (AR) Sandbox reads the elevation of actual sand and projects elevation information onto the sand’s surface (e.g., contour lines). Although over 600 institutions have built AR Sandboxes to help people interpret topographic maps, classroom studies using the AR Sandbox have not found significant gains on topographic map assessments. The present study is a 22 design testing the affordances of the AR Sandbox in a one on one, laboratory setting. In the first level of the study, participants …


To What Extent Might Beaver Dam Building Buffer Water Storage Losses Associated With A Declining Snowpack?, Konrad Hafen May 2017

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 …


A Bayesian Variable Selection Method With Applications To Spatial Data, Xiahan Tang May 2017

A Bayesian Variable Selection Method With Applications To Spatial Data, Xiahan Tang

Graduate Theses and Dissertations

This thesis first describes the general idea behind Bayes Inference, various sampling methods based on Bayes theorem and many examples. Then a Bayes approach to model selection, called Stochastic Search Variable Selection (SSVS) is discussed. It was originally proposed by George and McCulloch (1993). In a normal regression model where the number of covariates is large, only a small subset tend to be significant most of the times. This Bayes procedure specifies a mixture prior for each of the unknown regression coefficient, the mixture prior was originally proposed by Geweke (1996). This mixture prior will be updated as data becomes …


The Development Of A High Resolution Deep-Uv Spatial Heterodyne Raman Spectrometer, Nirmal Lamsal Jun 2016

The Development Of A High Resolution Deep-Uv Spatial Heterodyne Raman Spectrometer, Nirmal Lamsal

Theses and Dissertations

Raman spectroscopy is a light scattering technique that has a huge potential for standoff measurements in applications such as planetary exploration because a Raman spectrum provides a unique molecular fingerprint that can be used for unambiguous identification of target molecules. For this reason, NASA has selected a Raman spectrometer as one of the major instruments for its new Mars lander mission, Mars 2020, in the search for biomarkers that would be the indicators of past or present life. Raman scattering is strongest at UV wavelengths because of the inherent increase in the Raman cross section at shorter wavelengths and because …


Quantifying Transit Access In New York City: Formulating An Accessibility Index For Analyzing Spatial And Social Patterns Of Public Transportation, Maxwell S. Siegel May 2016

Quantifying Transit Access In New York City: Formulating An Accessibility Index For Analyzing Spatial And Social Patterns Of Public Transportation, Maxwell S. Siegel

Theses and Dissertations

This paper aims to analyze accessibility within New York City’s transportation system through creating unique accessibility indices. Indices are detailed and implemented using GIS, analyzing the distribution of transit need and access. Regression analyses are performed highlighting relationships between demographics and accessibility and recommendations for transit expansion are presented.


Bivariate Negative Binomial Hurdle With Random Spatial Effects, Robert Mcnutt Apr 2016

Bivariate Negative Binomial Hurdle With Random Spatial Effects, Robert Mcnutt

Dissertations

Count data with excess zeros widely occur in ecology, epidemiology, marketing, and many other disciplines. Mixture distributions consisting of a point mass at zero and a separate discrete distribution are often employed in regression models to account for excessive zero observations in the data. While Poisson models are very popular for count data, Negative Binomial models provide greater flexibility due to their ability to account for overdispersion.

This research focuses on developing a method for analyzing bivariate count data with excess zeros collected over a lattice. A bivariate Zero-Inflated Negative Binomial Hurdle (ZINBH) regression model with spatial random effects is …


A Novel Recurrent Convolutional Neural Network For Ocean And Weather Forecasting, Robert James Firth Jan 2016

A Novel Recurrent Convolutional Neural Network For Ocean And Weather Forecasting, Robert James Firth

LSU Doctoral Dissertations

Numerical weather prediction is a computationally expensive task that requires not only the numerical solution to a complex set of non-linear partial differential equations, but also the creation of a parameterization scheme to estimate sub-grid scale phenomenon. The proposed method is an alternative approach to developing a mesoscale meteorological model – a modified recurrent convolutional neural network that learns to simulate the solution to these equations. Along with an appropriate time integration scheme and learning algorithm, this method can be used to create multi-day forecasts for a large region. The learning method presented is an extended form of Backpropagation Through …


Modeling Spatially Varying Effects Of Chemical Mixtures, Jenna Czarnota Jan 2016

Modeling Spatially Varying Effects Of Chemical Mixtures, Jenna Czarnota

Theses and Dissertations

Cancer incidence is associated with exposures to multiple environmental chemicals, and geographic variation in cancer rates suggests the importance of accommodating spatially varying effects in the analysis of environmental chemical mixtures and disease risk. Traditional regression methods are challenged by the complex correlation patterns inherent among co-occurring chemicals, and the applicability of geographically weighted regression models is limited in the setting of environmental chemical risk analysis. In comparison to traditional methods, weighted quantile sum (WQS) regression performs well in the identification of important environmental exposures, but is limited by the assumption that effects are fixed over space. We present an …


Investigating Coastal Erosion Variability And Framework Geology Influence Along The Grand Strand, South Carolina, Aundrea Marie Dolan Jan 2016

Investigating Coastal Erosion Variability And Framework Geology Influence Along The Grand Strand, South Carolina, Aundrea Marie Dolan

Electronic Theses and Dissertations

Increasing erosional pressures along coastal systems require a better understanding of the mechanisms of natural and human-induced alterations. This is especially important in sediment-starved coastal systems where the effects from geologic framework may exert a disproportionate influence on shoreline behavior. Existing studies into geologic framework and shoreline variability are comprehensive and well documented; yet analysis into the spatial relationships between shoreline variability, lower shoreface morphodynamics, and framework in South Carolina is limited. The Grand Strand region of South Carolina has an extensive set of geophysical data, such as CHIRP seismic, sidescan sonar, borehole logs, and inner shelf cores. In addition, …


A Climatological Study Of Drought In Southern Michigan, Rudy Bartels Apr 2014

A Climatological Study Of Drought In Southern Michigan, Rudy Bartels

Masters Theses

Drought has become a reoccurring phenomenon throughout many regions around the world. Significant drought conditions have beenobserved overthe pastfive decades in relation to economic, social, and agricultural impacts. In this study, Southern Michigan is investigated over the past 52 years from 1960-2012. The Standardized Precipitation Index (SPI) will be calculated over a 6-month timescale from monthly precipitations. Three variables including 500-mb heights, surface pressure maps, and sea surface temperatures, will be correlated with the SPI using sliding correlations and Pearson's R correlation to determine any relations between these variables and precipitation variations. We will further investigate the five driest, wettest, …


No Fracking Way! A Study On The Spatial Patterns Of And Changes In Perception And Distance From A Michigan Horizontal Hydraulic Fracturing Site, Shannon Mcewen Apr 2014

No Fracking Way! A Study On The Spatial Patterns Of And Changes In Perception And Distance From A Michigan Horizontal Hydraulic Fracturing Site, Shannon Mcewen

Masters Theses

The research investigates whether Michigan residents' perception of risk from an oil and natural gas (ONG) well site that employs the use of horizontal hydraulic fracturing (fracking) changes with distance. The research goal is to determine if residents that live farther from a fracking site perceive it to be more dangerous than those who live closer. Secondary research goals include determining if increasing distance from a fracking site cause residents to overestimate their proximity to a fracking site and if gender and education levels have an effect on residents' perception levels. Data were collected from residents in three counties in …


An Applied Investigation Of Gaussian Markov Random Fields, Jessica Lyn Olsen Jun 2012

An Applied Investigation Of Gaussian Markov Random Fields, Jessica Lyn Olsen

Theses and Dissertations

Recently, Bayesian methods have become the essence of modern statistics, specifically, the ability to incorporate hierarchical models. In particular, correlated data, such as the data found in spatial and temporal applications, have benefited greatly from the development and application of Bayesian statistics. One particular application of Bayesian modeling is Gaussian Markov Random Fields. These methods have proven to be very useful in providing a framework for correlated data. I will demonstrate the power of GMRFs by applying this method to two sets of data; a set of temporal data involving car accidents in the UK and a set of spatial …


Scan-Based Near-Field Acoustical Holography On Partially Correlated Sources, Michael D. Gardner Aug 2009

Scan-Based Near-Field Acoustical Holography On Partially Correlated Sources, Michael D. Gardner

Theses and Dissertations

Scan-based near-field acoustical holography (NAH) is applied to partially correlated sources. Partial field decomposition via the virtual coherence method is used to implement the scan-based NAH. The background and theory of these methods are developed. Multiple stationary reference microphones are required for the partial field decomposition. Guidelines for reference microphone placement in the literature thus far have been limited. Improved guidelines for reference microphones are given after the results of two sets of experiments. The first set involves discrete, partially correlated sources, both physical and numerical. The second set of experiments is strictly numerical and involves continuous sources. Fewer microphones …


Optimal Candidate Generation In Spatial Co-Location Mining, Zhongshan Lin May 2009

Optimal Candidate Generation In Spatial Co-Location Mining, Zhongshan Lin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Existing spatial co-location algorithms based on levels suffer from generating extra, nonclique candidate instances. Thus, they require cliqueness checking at every level. In this thesis, a novel, spatial co-location mining algorithm that automatically generates co-located spatial features without generating any nonclique candidates at any level is proposed. Subsequently, this algorithm generates fewer candidates than other existing level-wise, co-location algorithms without losing any pertinent information. The benefits of this algorithm have been clearly observed at early stages in the mining process.


Simulation, Kriging, And Visualization Of Circular-Spatial Data, William James Morphet May 2009

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 …


Dynamics Of Spatial Pattern Formation: Cases Of Spikes And Droplets, Yuya Sasaki May 2007

Dynamics Of Spatial Pattern Formation: Cases Of Spikes And Droplets, Yuya Sasaki

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis studies the gradient system that forms spatial patterns such that the minimum distances of pairs among various points are maximized in the end. As this problem innately involves singularity issues, an extended system of the gradient system is proposed. Motivated by the spatial pattern suggested by a numerical example, this extended system is applied to a three-point problem and then to a two-point problem in a quotient space of ℝ2 modulo a lattice.