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Full-Text Articles in Physical Sciences and Mathematics

Changes In Bark Properties And Hydrology Following Prescribed Fire, Courtney Siegert, Anna Ilek, Adam Wade Jan 2022

Changes In Bark Properties And Hydrology Following Prescribed Fire, Courtney Siegert, Anna Ilek, Adam Wade

CFR Publications

No abstract provided.


Mathematical Model For Giraffe Population Dynamics, Huntir Bass Jan 2022

Mathematical Model For Giraffe Population Dynamics, Huntir Bass

Electronic Theses and Dissertations, 2020-2023

Since the 1980s the overall giraffe population has dropped at least 40% causing some researchers to label this rapid decline as the "Silent Extinction." Due to this plummet, understanding the behaviors of the giraffe population is absolutely necessary before they are on the brink of extinction. Through the usage of mathematical modeling methodologies, a general model is created to illustrate the relationship between juvenile and adult female giraffes through numerous interaction parameters. Variations on specific variables generate different simulations, which allows more biological accuracy. With each variation having an established coexistence equilibrium between the juvenile and adult female populations, the …


Various Dynamical Regimes, And Transitions From Homogeneous To Inhomogeneous Steady States In Nonlinear Systems With Delays And Diverse Couplings, Ryan Roopnarain Jan 2022

Various Dynamical Regimes, And Transitions From Homogeneous To Inhomogeneous Steady States In Nonlinear Systems With Delays And Diverse Couplings, Ryan Roopnarain

Electronic Theses and Dissertations, 2020-2023

This dissertation focuses on the effects of distributed delays modeled by 'weak generic kernels' on the collective behavior of coupled nonlinear systems. These distributed delays are introduced into several well-known periodic oscillators such as coupled Landau-Stuart and Van der Pol systems, as well as coupled chaotic Van der Pol-Rayleigh and Sprott systems, for a variety of couplings including diffusive, cyclic, or dynamic ones. The resulting system is then closed via the 'linear chain trick' and the linear stability analysis of the system and conditions for Hopf bifurcations that initiate oscillations are investigated. A variety of dynamical regimes and transitions between …


Methods And Characterization Of Topological And Disordered-Induced Protection Of Coherence In Quantum Systems, Sayandip Dhara Jan 2022

Methods And Characterization Of Topological And Disordered-Induced Protection Of Coherence In Quantum Systems, Sayandip Dhara

Electronic Theses and Dissertations, 2020-2023

Quantum computers can efficiently simulate natural processes and solve certain types of mathematical problems. Two of the key issues preventing the development of platforms to realize a scalable quantum machine are the decoherence of the qubits due to the interaction with the environment and the existence of a large overhead to correct errors. Although there already exist noisy intermediate-scale quantum machines, we still need to improve much to be able to solve problems faster than the already existing classical computers. In this dissertation, we explore two approaches to tackle both issues. We propose a scheme where, using quasi-Majorana zero modes …


Cybersecurity & Correctional Institutions, Kelly Himelwright Jan 2022

Cybersecurity & Correctional Institutions, Kelly Himelwright

Cybersecurity Undergraduate Research Showcase

Cybersecurity is becoming an increasingly important aspect of correctional operations. To properly maintain security, more jails and prisons are using comprehensive cyber protection techniques. Correctional facilities face risks that were perhaps unimaginable only a few decades ago. Many organizations have used information technology to help them run their businesses, but few have the resources or vision to foresee and adequately manage the cyber dangers that come with it. Institutions need to be more aware of these hazards, as well as have more information security experts on staff.


Surficial Geologic Map Of The Constantine 7.5-Minute Quadrangle, Kentucky, Maxwell L. Hammond Iii, Antonia E. Bottoms, Matthew Massey, Emily Morris, Michele Mchugh Jan 2022

Surficial Geologic Map Of The Constantine 7.5-Minute Quadrangle, Kentucky, Maxwell L. Hammond Iii, Antonia E. Bottoms, Matthew Massey, Emily Morris, Michele Mchugh

Contract Reports--KGS

The Constantine 7.5-minute quadrangle is located west of Elizabethtown along the boundary of Hardin and Breckinridge Counties. The quadrangle lies along the northern section of the Dripping Springs Escarpment, which separates the Mammoth Cave Plateau and Pennyroyal regions of the Mississippian Sinkhole Plain physiographic province (McFarlan, 1943). Topography is mostly characterized by high-elevation plateaus, ridges, and knobs of the Mammoth Cave Plateau (up to 919 ft), which have been intensely dissected by the Rough River and its tributaries (down to 516 ft). A small area of the Pennyroyal extends into the eastern part of the quadrangle, which is marked by …


Actuarial Credibility Approach In Adjusting Initial Cost Estimates Of Transport Infrastructure Projects, Bartłomiej Rokicki, Krzysztof Ostaszewski Jan 2022

Actuarial Credibility Approach In Adjusting Initial Cost Estimates Of Transport Infrastructure Projects, Bartłomiej Rokicki, Krzysztof Ostaszewski

Faculty Publications – Mathematics

This paper presents a novel methodology based on the modified actuarial credibility approach. It allows for the adjustment of initial cost estimates of public infrastructure projects by accounting for the additional risk/uncertainty factor. Hence, it offers an interesting alternative to other existing forecasting methods. We test our approach by applying data for over 300 major infrastructure projects implemented in Poland between 2004 and 2020. We prove that, despite its simplicity, the actuarial credibility approach can deliver accurate cost estimates compared to more complex methods such as regression analysis (OLS) or machine learning (LASSO). In particular, we show that, although the …


The Role Of Interactive Features Within A Mathematics Storybook In Interpreting A Conflict And Conflict Resolution: The Case Of Three Fifth Graders, Mahtob Aqazade Jan 2022

The Role Of Interactive Features Within A Mathematics Storybook In Interpreting A Conflict And Conflict Resolution: The Case Of Three Fifth Graders, Mahtob Aqazade

Faculty Publications – Mathematics

Students often experience cognitive conflicts when trying to interpret negative numbers’ order and values because they do not correspond to their prior whole number knowledge. One way to trigger students’ cognitive conflicts and support their conflict resolution meaningfully is through stories. Thus, I used a temperature-related mathematics storybook—Temperature Turmoil—to highlight the cognitive conflict students often experience because of relying on the integers’ absolute value and introduce conflict resolution (i.e., integers have both absolute value and directed value). By incorporating interactive features, I used a multiple-case approach to describe three fifth graders’ cognitive conflict and conflict resolution experiences. Harry, Lola, and …


Using Short Bursts To Optimize Redistricting In Georgia, Vedika Vishweshwar Jan 2022

Using Short Bursts To Optimize Redistricting In Georgia, Vedika Vishweshwar

CMC Senior Theses

Identifying extreme outliers in large state spaces is a difficult prob-
lem. I consider this problem in the context of finding political district-
ing plans that maximize the number of districts in which the majority
of the population is from a minority group, such as African Americans.
Since the set of all possible districting plans is enormous and unfeasi-
ble to examine in practice, this paper proposes a sampling method to
find these outlying plans. Specifically, this paper experiments with short
bursts in the context of minority voting rights in Georgia. Short bursts
are a type of Markov Chain in …


Dynamic Nonlinear Gaussian Model For Inferring A Graph Structure On Time Series, Abhinuv Uppal Jan 2022

Dynamic Nonlinear Gaussian Model For Inferring A Graph Structure On Time Series, Abhinuv Uppal

CMC Senior Theses

In many applications of graph analytics, the optimal graph construction is not always straightforward. I propose a novel algorithm to dynamically infer a graph structure on multiple time series by first imposing a state evolution equation on the graph and deriving the necessary equations to convert it into a maximum likelihood optimization problem. The state evolution equation guarantees that edge weights contain predictive power by construction. After running experiments on simulated data, it appears the required optimization is likely non-convex and does not generally produce results significantly better than randomly tweaking parameters, so it is not feasible to use in …


Analyzing Marriage Statistics As Recorded In The Journal Of The American Statistical Association From 1889 To 2012, Annalee Soohoo Jan 2022

Analyzing Marriage Statistics As Recorded In The Journal Of The American Statistical Association From 1889 To 2012, Annalee Soohoo

CMC Senior Theses

The United States has been tracking American marriage statistics since its founding. According to the United States Census Bureau, “marital status and marital history data help federal agencies understand marriage trends, forecast future needs of programs that have spousal benefits, and measure the effects of policies and programs that focus on the well-being of families, including tax policies and financial assistance programs.”[1] With such a wide scope of applications, it is understandable why marriage statistics are so highly studied and well-documented.

This thesis will analyze American marriage patterns over the past 100 years as documented in the Journal of …


Energy As A Limiting Factor In Neuronal Seizure Control: A Mathematical Model, Sophia E. Epstein Jan 2022

Energy As A Limiting Factor In Neuronal Seizure Control: A Mathematical Model, Sophia E. Epstein

CMC Senior Theses

The majority of seizures are self-limiting. Within a few minutes, the observed neuronal synchrony and deviant dynamics of a tonic-clonic or generalized seizure often terminate. However, a small epilesia partialis continua can occur for years. The mechanisms that regulate subcortical activity of neuronal firing and seizure control are poorly understood. Published studies, however, through PET scans, ketogenic treatments, and in vivo mouse experiments, observe hypermetabolism followed by metabolic suppression. These observations indicate that energy can play a key role in mediating seizure dynamics. In this research, I seek to explore this hypothesis and propose a mathematical framework to model how …


Mary Eleanor Spear's Importance To The History Of Statistical Visualization, Melanie Williams Jan 2022

Mary Eleanor Spear's Importance To The History Of Statistical Visualization, Melanie Williams

CMC Senior Theses

This paper will demonstrate why Mary Eleanor Spear (1897-1986) is an important figure in the history of statistical visualization. She lead an impressive career working in the federal government as a data analyst before "data analyst" became a thing. She wrote and illustrated two comprehensive textbooks which furthered the art of statistical visualization. Her textbooks cover extensive graphing knowledge still valuable to statisticians and viewers today. Most notable of her works is her development of the box plot. In addition to Spear's career and contributions, this paper will also address the lack of female representation in science, technology, engineering, and …


Predicting Outcomes Of El Clásico Using Random Forests And Extreme Gradient Boosting, Emanuel Jarquin Jan 2022

Predicting Outcomes Of El Clásico Using Random Forests And Extreme Gradient Boosting, Emanuel Jarquin

CMC Senior Theses

In the modern era, sports betting is becoming increasingly popular. This is especially true in the realm of soccer (or ‘football’ as it is known outside the United States). As a result, the concept of attempting to predict the outcomes of soccer matches using machine learning has garnered much attention in recent years. In this thesis, I utilize well-known machine learning techniques to predict the outcomes of El Clásico matchups and compare the predictive performance of these techniques. The predictive methods employed for this thesis are random forests using the party package in R and extreme gradient boosting using the …


Advanced Full-Text Search Based On Synonyms In Postgres, Joey Bodoia Jan 2022

Advanced Full-Text Search Based On Synonyms In Postgres, Joey Bodoia

CMC Senior Theses

This paper discusses the advanced full-text search queries based on synonyms that are supported in Chajda, which is a postgres extension and corresponding python library for highly multi-lingual full-text search in postgres. This discussion will include the motivations for using advanced queries based on synonyms, examples of how to use these advanced queries in Chajda, current limitiations of the advanced queries, and performance testing of the advanced queries.


Containing Compounding Container Congestion, Curtis Salinger Jan 2022

Containing Compounding Container Congestion, Curtis Salinger

CMC Senior Theses

The Covid-19 pandemic caused major disruptions throughout the container shipping supply chain. Professor Dongping Song of Liverpool University wrote a paper discussing the logistical vulnerabilities in the supply chain, including the issue of congestion in ports. This paper examines the Port of Los Angeles from 2018-2021 as it relates to Song’s paper to see how its operations were impacted during the Covid-19 timeframe. It is found that labor shortages, chassis shortages, and change in trade behavior each contributed to the congestion. Unfortunately, the implemented policies were insufficient to bolster the port against sustained challenges and congestion continues to worsen.


S-Type Stars: Lao Line List For The B²Σ⁺-X²Σ⁺ Band System, P. F. Bernath, Randika Dodangodage, J. Liévin Jan 2022

S-Type Stars: Lao Line List For The B²Σ⁺-X²Σ⁺ Band System, P. F. Bernath, Randika Dodangodage, J. Liévin

Chemistry & Biochemistry Faculty Publications

LaO bands are a characteristic feature in the spectrum of cool S-type stars. La is made primarily by the s-process during the asymptotic giant branch phase of stellar evolution. The B2Σ+–X2Σ+ and A2Π–X2Σ+ band systems can be used to determine the La abundances in cool S stars. The bands of the B2Σ+–X2Σ+ with v' and v" ⩽ 5 have been rotationally analyzed from an emission spectrum from a carbon furnace. Line strengths are calculated using an ab initio transition dipole …


Processperformance: A Portable And Easy-To-Use Tool To Measure Resource Consumption Of Running Processes, Miguel Garcia, Jose Quiroga, Francisco Ortin Jan 2022

Processperformance: A Portable And Easy-To-Use Tool To Measure Resource Consumption Of Running Processes, Miguel Garcia, Jose Quiroga, Francisco Ortin

Department of Mathematics Publications

The measurement of the resources consumed by an application at runtime is an important task in different scenarios such as program optimization, malware and bug detection, and hardware scaling. Although different tools exist for this purpose, they sometimes show some limitations such as operating system and hardware dependencies, performance overhead, and usage complexity. For this reason, we create ProcessPerformance, a portable and easy-to-use command-line tool that provides information about the CPU, memory, and network resources consumed by any combination of running processes. It also avoids the performance overhead caused by software and binary code injection.


Satdbailiff- Mining And Tracking Self-Admitted Technical Debt, Mohamed Wiem Mkaouer, Eman Abdullah Alomar, Ben Christians, Mihal Busho, Ahmed Hamad Alkhalid, Christian D. Newman Jan 2022

Satdbailiff- Mining And Tracking Self-Admitted Technical Debt, Mohamed Wiem Mkaouer, Eman Abdullah Alomar, Ben Christians, Mihal Busho, Ahmed Hamad Alkhalid, Christian D. Newman

Articles

Self-Admitted Technical Debt (SATD) is a metaphorical concept to describe the self-documented addition of technical debt to a software project in the form of source code comments. SATD can linger in projects and degrade source-code quality, but it can also be more visible than unintentionally added or undocumented technical debt. Understanding the implications of adding SATD to a software project is important because developers can benefit from a better understanding of the quality trade-offs they are making. However, empirical studies, analyzing the survivability and removal of SATD comments, are challenged by potential code changes or SATD comment updates that may …


College Of Natural Sciences Newsletter, January 2022, College Of Natural Sciences Jan 2022

College Of Natural Sciences Newsletter, January 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 1

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Outreach in Harrisburg, SD
Page 4 Geography Alumni Named Among 'Highly Cited Researchers', 53rd Annual Geography Convention
Page 5 Geography Convention Speakers, Brookings/SDSU Day
Page 6 Media Coverage of Natural Sciences
Page 7 Open PRAIRIE Data
Page 8 Fall 2021 Dean's List
Page 9 Fall 2021 Dean's List, cont.


A Cloud Computing-Based Dashboard For The Visualization Of Motivational Interviewing Metrics, E Jinq Heng Jan 2022

A Cloud Computing-Based Dashboard For The Visualization Of Motivational Interviewing Metrics, E Jinq Heng

Browse all Theses and Dissertations

Motivational Interviewing (MI) is an evidence-based brief interventional technique that has been demonstrated to be effective in triggering behavior change in patients. To facilitate behavior change, healthcare practitioners adopt a nonconfrontational, empathetic dialogic style, a core component of MI. Despite its advantages, MI has been severely underutilized mainly due to the cognitive overload on the part of the MI dialogue evaluator, who has to assess MI dialogue in real-time and calculate MI characteristic metrics (number of open-ended questions, close-ended questions, reflection, and scale-based sentences) for immediate post-session evaluation both in MI training and clinical settings. To automate dialogue assessment and …


Using Remote Sensing And Machine Learning To Locate Groundwater Discharge To Salmon-Bearing Streams, Mary E. Gerlach, Kai C. Rains, Edgar J. Guerrón-Orejuela, William J. Kleindl, Joni Downs, Shawn M. Landry, Mark C. Rains Jan 2022

Using Remote Sensing And Machine Learning To Locate Groundwater Discharge To Salmon-Bearing Streams, Mary E. Gerlach, Kai C. Rains, Edgar J. Guerrón-Orejuela, William J. Kleindl, Joni Downs, Shawn M. Landry, Mark C. Rains

School of Geosciences Faculty and Staff Publications

We hypothesized topographic features alone could be used to locate groundwater discharge, but only where diagnostic topographic signatures could first be identified through the use of limited field observations and geologic data. We built a geodatabase from geologic and topographic data, with the geologic data only covering ~40% of the study area and topographic data derived from airborne LiDAR covering the entire study area. We identified two types of groundwater discharge: shallow hillslope groundwater discharge, commonly manifested as diffuse seeps, and aquifer-outcrop groundwater discharge, commonly manifested as springs. We developed multistep manual procedures that allowed us to accurately predict the …


Variable Element Enrichment Sources And Contributions To Volcanic Rocks Along The Lesser Antilles Island Arc, Zachary D. Atlas, Aurélie Germa, Brenna Boss, Osvaldo Meireles, Ami Ward, Jeffrey G. Ryan Jan 2022

Variable Element Enrichment Sources And Contributions To Volcanic Rocks Along The Lesser Antilles Island Arc, Zachary D. Atlas, Aurélie Germa, Brenna Boss, Osvaldo Meireles, Ami Ward, Jeffrey G. Ryan

School of Geosciences Faculty and Staff Publications

Understanding relationships between different components involved in subduction-related recycling of sediment at arc volcanic systems has long been a focus of study. It is generally understood that volcanic arc lavas incorporate materials from the down-going slab including fluids, fluid mobile elements (FME), and fluid modified large ion lithophile elements (LILE), largely derived from subducted sediments and serpentinized ultramafic rocks. Past studies have presumed bulk sediment contributions rather than addressing localized variations in sediment composition. We examine trace element variability along the Lesser Antilles Island Arc (LAIA) and show that sediment inputs via fluid transfer to the mantle wedge are necessary …


Under The Surface: Pressure-Induced Planetary-Scale Waves, Volcanic Lightning, And Gaseous Clouds Caused By The Submarine Eruption Of Hunga Tonga-Hunga Ha'apai Volcano, David A. Yuen, Melissa A. Scruggs, Frank J. Spera, Yingcai Zheng, Hao Hu, Stephen R. Mcnutt, Glenn Thompson, Kyle Mandli, Barry R. Keller, Songqiao Shawn Wei, Zhigang Peng, Zili Zhou, Francesco Mulargia, Yuichiro Tanioka Jan 2022

Under The Surface: Pressure-Induced Planetary-Scale Waves, Volcanic Lightning, And Gaseous Clouds Caused By The Submarine Eruption Of Hunga Tonga-Hunga Ha'apai Volcano, David A. Yuen, Melissa A. Scruggs, Frank J. Spera, Yingcai Zheng, Hao Hu, Stephen R. Mcnutt, Glenn Thompson, Kyle Mandli, Barry R. Keller, Songqiao Shawn Wei, Zhigang Peng, Zili Zhou, Francesco Mulargia, Yuichiro Tanioka

School of Geosciences Faculty and Staff Publications

We present a narrative of the eruptive events culminating in the cataclysmic January 15, 2022 eruption of Hunga Tonga-Hunga Ha'apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and lightning data available within the first few weeks after the eruption occurred. The first hour of eruptive activity produced fast-propagating tsunami waves, long-period seismic waves, loud audible sound waves, infrasonic waves, exceptionally intense volcanic lightning and an unsteady volcanic plume that transiently reached—at 58 km—the Earth's mesosphere. Energetic seismic signals were recorded worldwide and the globally stacked seismogram showed episodic seismic events within the most intense periods …


A Deep Active Learning Approach To The Automatic Classification Of Volcano-Seismic Events, Grace F. Manley, Tamsin A. Mather, David M. Pyle, David A. Clifton, Mel Rodgers, Glenn Thompson, John Makario Londoño Jan 2022

A Deep Active Learning Approach To The Automatic Classification Of Volcano-Seismic Events, Grace F. Manley, Tamsin A. Mather, David M. Pyle, David A. Clifton, Mel Rodgers, Glenn Thompson, John Makario Londoño

School of Geosciences Faculty and Staff Publications

Volcano-seismic event classification represents a fundamental component of volcanic monitoring. Recent advances in techniques for the automatic classification of volcano-seismic events using supervised deep learning models achieve high accuracy. However, these deep learning models require a large, labelled training dataset to successfully train a generalisable model. We develop an approach to volcano-seismic event classification making use of active learning, where a machine learning model actively selects the training data which it learns from. We apply a diversity-based active learning approach, which works by selecting new training points which are most dissimilar from points already in the model according to a …


Spatial Variation Of Subduction Zone Fluids During Progressive Subduction: Insights From Serpentinite Mud Volcanoes, Catriona D. Menzies, Roy E. Price, Jeffrey Ryan, Olivier Sissmann, Ken Takai, C. Geoffrey Wheat Jan 2022

Spatial Variation Of Subduction Zone Fluids During Progressive Subduction: Insights From Serpentinite Mud Volcanoes, Catriona D. Menzies, Roy E. Price, Jeffrey Ryan, Olivier Sissmann, Ken Takai, C. Geoffrey Wheat

School of Geosciences Faculty and Staff Publications

Geological processes at subduction zones control seismicity, plutonism and volcanism, and geochemical cycling between the oceans, crust, and mantle. The down-going plate experiences metamorphism, and the associated dehydration and fluid flow alters the physical properties of the plate interface and mantle wedge, as well as controlling the composition of material descending into the mantle. Any direct study of slab evolution during subduction is inhibited by the prohibitive depths at which these processes occur. To examine these processes we use serpentinite mud volcanoes in the Mariana forearc, that permit sampling of serpentinite materials and their pore waters that …


Under The Surface: Pressure-Induced Planetary-Scale Waves, Volcanic Lightning, And Gaseous Clouds Caused By The Submarine Eruption Of Hunga Tonga-Hunga Ha’Apai Volcano Provide An Excellent Research Opportunity, David A. Yuen, Melissa A. Scruggs, Frank J. Spera, Yingcai Zheng, Hao Hu, Stephen R. Mcnutt, Glenn Thompson, Kyle Mandli, Barry R. Keller, Songqiao Shawn Wei, Zhigang Peng, Zili Zhou, Francesco Mulargia, Yuichiro Tanioka Jan 2022

Under The Surface: Pressure-Induced Planetary-Scale Waves, Volcanic Lightning, And Gaseous Clouds Caused By The Submarine Eruption Of Hunga Tonga-Hunga Ha’Apai Volcano Provide An Excellent Research Opportunity, David A. Yuen, Melissa A. Scruggs, Frank J. Spera, Yingcai Zheng, Hao Hu, Stephen R. Mcnutt, Glenn Thompson, Kyle Mandli, Barry R. Keller, Songqiao Shawn Wei, Zhigang Peng, Zili Zhou, Francesco Mulargia, Yuichiro Tanioka

School of Geosciences Faculty and Staff Publications

We present a narrative of the eruptive events culminating in the cataclysmic 15 January 2022 eruption of Hunga Tonga-Hunga Ha’apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and lightning data available within the first few weeks after the eruption occurred. The first hour of eruptive activity produced fast-propagating tsunami waves, long-period seismic waves, loud audible sound waves, infrasonic waves, exceptionally intense volcanic lightning and an unsteady volcanic plume that transiently reached—at 58 km—the Earth’s mesosphere. Energetic seismic signals were recorded worldwide and the globally stacked seismogram showed episodic seismic events within the most intense periods of phreatoplinian activity, …


Uncertainty Quantification Of Eruption Source Parameters Estimated From Tephra Fall Deposits, R. Constantinescu, J. T. White, C. B. Connor, A. Hopulele-Gligor, S. Charbonnier, J.-C. Thouret, J. M. Lindsay, D. Bertin Jan 2022

Uncertainty Quantification Of Eruption Source Parameters Estimated From Tephra Fall Deposits, R. Constantinescu, J. T. White, C. B. Connor, A. Hopulele-Gligor, S. Charbonnier, J.-C. Thouret, J. M. Lindsay, D. Bertin

School of Geosciences Faculty and Staff Publications

Uncertainty quantification (UQ) in eruption source parameters, like tephra volume, plume height, and umbrella cloud radius, is a challenge for volcano scientists because tephra deposits are often sparsely sampled due to burial, erosion, and related factors. We find that UQ is improved by coupling an advection-diffusion model with two Bayesian inversion approaches: (a) a robust but computationally expensive Generalized Likelihood Uncertainty Estimation algorithm, and (b) a more approximate but inexpensive parameter estimation algorithm combined with first-order, second-moment uncertainty estimation. We apply the two inversion methods to one sparsely sampled tephra fall unit from the 2070 BP El Misti (Peru) eruption …


Impact Of Model Choice In Predicting Urban Forest Storm Damage When Data Is Uncertain, Casey Lambert, Shawn Landry, Michael G. Andreu, Andrew Koeser, Gregory Starr, Christina Staudhammer Jan 2022

Impact Of Model Choice In Predicting Urban Forest Storm Damage When Data Is Uncertain, Casey Lambert, Shawn Landry, Michael G. Andreu, Andrew Koeser, Gregory Starr, Christina Staudhammer

School of Geosciences Faculty and Staff Publications

Research that illuminates causes of urban forest storm damage is valuable for planning and management. However, logistical and safety concerns often delay post-storm surveys in urban areas; thus, surveys may include observations with unverified sources of damage. While this uncertainty is often ignored, it can make up a high proportion of the number of damaged trees. The goal of this research was to improve understanding of techniques for modeling storm damage in urban forests. Using urban forest storm damage inventories collected in Florida, post-Hurricane Irma (2017), we tested how different imputation methods, modeling procedures, and damage frequency levels could impact …


Can Environmental Law Solve The "Forever Chemical" Problem?, Mark P. Nevitt, Robert V. Percival Jan 2022

Can Environmental Law Solve The "Forever Chemical" Problem?, Mark P. Nevitt, Robert V. Percival

Faculty Articles

Although federal environmental law purports to provide the public with comprehensive protection against chemical risks, the U.S. chemical industry is characterized by self­ regulation. This self-regulation is exemplified by the dangers posed by per- and polyfluoroalkyl substances (''PFAS'')­ broad classes of persistent toxic substances that have now entered nearly every American's bloodstream and hundreds of public drinking water systems. Despite data linking exposure to these "forever chemicals" to cancer, infertility, and a host of other public health harms, environmental law has failed to safeguard the American people from PFAS' toxic legacy. How did this occur? And what should be done …