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Full-Text Articles in Physical Sciences and Mathematics

The Usage Of Band Ratios To Predict Lake Water Quality Parameters Using Sentinel-2 L1c Imagery, Austin Spoor, Ho-Seop Cha Feb 2024

The Usage Of Band Ratios To Predict Lake Water Quality Parameters Using Sentinel-2 L1c Imagery, Austin Spoor, Ho-Seop Cha

International Journal of Geospatial and Environmental Research

Band ratios using remote imagery can be useful for monitoring large bodies of water when high quality imagery is available. Sentinel-2 satellite imagery provides frequent, high-resolution coverage of the globe. This study set out to test the usefulness of existing band ratios for estimating chlorophyll a (CHL-a), dissolved organic carbon (DOC), and turbidity with Sentinel-2 imagery. USGS in-situ data was matched to Sentinel-2 imagery of Beaver Lake, Arkansas taken August 2015 to July 2019 and the dark spectrum fitting (DSF) atmospheric correction method in ACOLITE was applied to generate surface reflectance values. CHL-a was estimated using two …


Accuracy Assessment Of Measuring Linear And Areal Features In Aerial Imagery, I-Kuai Hung, David L. Kulhavy, Daniel R. Unger, Reid A. Viegut, Yanli Zhang, Nicholas C. Schiwitz Dec 2023

Accuracy Assessment Of Measuring Linear And Areal Features In Aerial Imagery, I-Kuai Hung, David L. Kulhavy, Daniel R. Unger, Reid A. Viegut, Yanli Zhang, Nicholas C. Schiwitz

International Journal of Geospatial and Environmental Research

As part of natural resource education in the Arthur Temple College of Forestry and Agriculture at Stephen F. Austin State University (SFASU), students were instructed to take areal and linear measurements of grounds remotely using available platforms including aerial orthomosaic derived from UAS (unmanned aerial system) acquired imagery, Google Earth Pro, and Pictometry. The onscreen measurement was conducted at five different map scales, 1/1000, 1/2000, 1/3000, 1/4000, and 1/5000. Accuracy of the measurements was assessed by comparing the onscreen measurements to ground truth data verified with a measuring tape. Results show that measurements based on the UAS were more accurate …


Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle Aug 2023

Nutrient Dynamics Of Freshwater Estuarine Sediments Disturbed By Dredging, Ryan Allan John Roekle

Theses and Dissertations

This study examined the nutrient environment of sediments in the Milwaukee River estuary and the dynamics of those nutrients during simulated disturbance experiments within the context of large-scale dredging remediation. Surface sediments were collected from throughout the Milwaukee estuary (including river, harbor, and nearshore stations) by PONAR, centrifuged to separate porewater (interstitial water) from solid material, and filtered to further isolate and stabilize dissolved material. Porewaters were analyzed for dissolved nutrients including ammoniacal nitrogen (AN), nitrate, nitrite, and soluble reactive phosphorus (SRP). Surface sediment porewaters within the estuary were often highly enriched in AN and SRP, which were often 10-2000x …


Benthic Algal And Macroinvertebrate Response To The Removal Of Dreissenid Mussels In The Nearshore Zone Of Lake Michigan, Tyler Alexander Kunze Aug 2023

Benthic Algal And Macroinvertebrate Response To The Removal Of Dreissenid Mussels In The Nearshore Zone Of Lake Michigan, Tyler Alexander Kunze

Theses and Dissertations

Dreissenid mussels (Dreissena polymorpha and Dreissena rostriformis bugensis) have changed the fundamental community structure and biogeochemical processes of the Lake Michigan nearshore zone. There is evidence that dreissenids promote the nuisance growth of benthic algae, especially Cladophora sp. In addition, benthic macroinvertebrates have benefitted from the presence of dreissenid mussels due to the increased structural complexity along with greater nutrient availability in the benthos. These effects of the dreissenid mussel invasion are well documented; however, little is known about how these systems respond to the removal of dreissenid mussels from a once-populated area. Therefore, it is important to further our …


Comparing Drone2map Versus Pix4dmapper When Creating Orthophoto Mosaics Over Homogeneous Land Features, Victoria Williams, Daniel R. Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang Jul 2023

Comparing Drone2map Versus Pix4dmapper When Creating Orthophoto Mosaics Over Homogeneous Land Features, Victoria Williams, Daniel R. Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang

International Journal of Geospatial and Environmental Research

This study evaluated two popular software packages currently used within the natural resources profession to create orthophoto mosaics: Drone2Map and Pix4Dmapper. Of particular concern was how effective these two software packages would perform in creating orthophoto mosaics over a city park in East Texas consisting of forest, open grass, and urban concrete surrounding a lake. Two drone flights over the city park were conducted. One flight was at 76 meters (250 feet) above ground with a single pass configuration. The other flight was at 122 meters (400 feet) above ground with a double pass configuration. Upon the completion of each …


The Role Of Energy Storage In The Transition Toward A Carbon-Neutral Economy, Siyu Feng May 2023

The Role Of Energy Storage In The Transition Toward A Carbon-Neutral Economy, Siyu Feng

Theses and Dissertations

Energy transitions to less-carbon intense technologies, such as wind and solar energy, in the electricity, sector are crucial to realizing international climate goals because the electricity sector has been one of the main global carbon emitter for decades, and environmental plans in most countries involve electrifying heavily polluting industries with clean electricity generation. The intermittency problem of renewable energy has been the main stumbling block on the path, and energy storage is now referred to as the key in these transitions because it can boost renewable energy use while also improving the efficiency of conventional power plants (Hall and Bain, …


Aestheticization As A Type Of Erasure: An Ecocritical Examination Of Three Etchings From James Mcneill Whistler's 'Thames Set' (1859-1871), Sydney Ion May 2023

Aestheticization As A Type Of Erasure: An Ecocritical Examination Of Three Etchings From James Mcneill Whistler's 'Thames Set' (1859-1871), Sydney Ion

Theses and Dissertations

This thesis explores “A Series of Sixteen Etchings of Scenes on the Thames” (1859-1871), Thames Set, by James Abbott McNeill Whistler (1834-1903), a group of etchings that negotiates the effects of the “Great Stink” on the Thames riverbank and its people. I argue that the series exhibits a strange paradox: the intentional exclusion of accurate environmental elements and sensorial details to achieve a romanticized nostalgic framework that serves Whistler’s aesthetic ideals. This aestheticization of the environmental crisis is the foundation from which Whistler’s modernization grew. Recent research has understood the Thames Set as evidence of Whistler’s involvement in depicting lower-class …


Special Thanks To Reviewers 2021-2022, Woonsup Choi Mar 2023

Special Thanks To Reviewers 2021-2022, Woonsup Choi

International Journal of Geospatial and Environmental Research

Sincere thanks are extended to the individuals who reviewed manuscripts for International Journal of Geospatial and Environmental Research during the period from 1 January 2021 to 31 December 2022.


Common Ground Over Common Water: Defining The Public Interest In The Milwaukee Watershed, Thomas Anthony Gentine Dec 2022

Common Ground Over Common Water: Defining The Public Interest In The Milwaukee Watershed, Thomas Anthony Gentine

Theses and Dissertations

My dissertation examines government and nongovernment entities’ attempts to restore and protect the use and health of the Milwaukee River and its watershed from 1960 to 2000. Under Mayor Henry Maier’s leadership, Milwaukee worked to reclaim the urban riverway to stimulate economic growth. However, state and federal representatives, after the passage of the 1965 Water Quality Act, demanded that the city government prioritize updating the combined storm and sewer system to lessen pollution in the Milwaukee River. At the same time, other groups worked to save rural areas from unplanned development and further degradation of the waterway. Influential groups included …


Exploring The Spatial Distribution Of Air Pollutants And Covid-19 Death Rate: A Case Study For Los Angeles County, California, Akhil Mandalapu, Junfeng Jiao, Amin Azimian May 2022

Exploring The Spatial Distribution Of Air Pollutants And Covid-19 Death Rate: A Case Study For Los Angeles County, California, Akhil Mandalapu, Junfeng Jiao, Amin Azimian

International Journal of Geospatial and Environmental Research

Objective

Since March 2020, COVID-19 has rapidly spread across the world with over 240 million cases and over 5 million deaths as of November 2021. It has been unclear what role air pollutants may play in exacerbating respiratory illnesses such as COVID-19 due to their interaction with the respiratory system. The association with air pollutants and COVID-19 severity has been explored at the regional and metropolitan area, however it is unclear if such an association is consistent at the neighborhood level.

Methods

Weekly death rates from COVID-19 from March 2020 to November 2021 were compared using one-sided unpaired t-tests across …


Influence Of Nutrients And The Native On E. Coli Survival In The Beach Environment, Brigid Meyers May 2022

Influence Of Nutrients And The Native On E. Coli Survival In The Beach Environment, Brigid Meyers

Theses and Dissertations

E. coli is used as an indicator for water quality to determine if water poses a health risk for pathogens. Past research has shown that E. coli is present in high numbers in freshwater beach sands distinct from fecal pollution events, yet the precise mechanism for their persistence in not well understood. Persistent E. coli populations in sand can resuspend into adjacent water and lead to increased beach closures when no threat is present. This work identifies factors that influence the survival of E. coli in sand using laboratory microcosms to replicate beach conditions. Microcosms were deployed to examine the …


Tackling Chloride Pollution In Southeastern Wisconsin: Halophilic Bacterial Indicators And Policy Alternatives, Elexius Kaitlyn Passante May 2022

Tackling Chloride Pollution In Southeastern Wisconsin: Halophilic Bacterial Indicators And Policy Alternatives, Elexius Kaitlyn Passante

Theses and Dissertations

There are few biological indicators for freshwater systems subjected to high chloride levels. Freshwater systems receive many forms of chloride such as road salts (e.g., NaCl, CaCl2, MgCl2), fertilizers (e.g., KCl), and year-round water softener pollution. The goal our study was to investigate Halomonadaceae populations as prospective biological indicators of chloride-impacted freshwaters. The bacterial family Halomonadaceae are halophiles that generally require the presence of salt to survive, which makes them an attractive candidate in determining chloride impaired areas. Field sediment surveys assessed how salt tolerant and halophilic bacteria abundance corresponded to chloride and conductivity measurements. Colony forming unit (CFU) counts …


Baseflow Variability Due To Changes In Climate, Basin Characteristics, And Groundwater Withdrawals In The State Of Wisconsin, Usa, Susan Borchardt May 2022

Baseflow Variability Due To Changes In Climate, Basin Characteristics, And Groundwater Withdrawals In The State Of Wisconsin, Usa, Susan Borchardt

Theses and Dissertations

ABSTRACT

BASEFLOW VARIABILITY DUE TO CHANGES IN CLIMATE,BASIN CHARACTERISTICS, AND GROUNDWATER WITHDRAWALS IN THE STATE OF WISCONSIN, USA

bySusan Borchardt The University of Wisconsin-Milwaukee, 2022 Under the Supervision of Professor Woonsup Choi

In Wisconsin, the number of high-capacity wells has increased substantially, and concerns have been raised about their impact on both groundwater levels and streamflow. At the same time Wisconsin’s climate has been changing, and both the annual precipitation (5%) and temperature (1.5oC) have been trending upward over the last 68 years and both are predicted to increase into the future. This study attempted to demonstrate the simultaneous effects …


What Geographers Research: An Analysis Of Geography Topics, Clusters, And Trends Using A Keyword Network Analysis Approach And The 2000-2019 Aag Conference Presentations, Jeong C. Seong, Chul Sue Hwang, Ana Stanescu, Youngho Lee, Yubin Lee Feb 2022

What Geographers Research: An Analysis Of Geography Topics, Clusters, And Trends Using A Keyword Network Analysis Approach And The 2000-2019 Aag Conference Presentations, Jeong C. Seong, Chul Sue Hwang, Ana Stanescu, Youngho Lee, Yubin Lee

International Journal of Geospatial and Environmental Research

The spectrum of geographic research topics is very broad, and several thousands of research projects are presented at AAG annual conferences. This research aims at analyzing geography research topics, clusters, and trends using conference presentation data. We analyzed the 2000-2019 AAG conference presentations with keyword network analysis methods. The most frequently used keywords during the 20-year span were GIS, followed by Remote Sensing, Climate Change, Urban, China, Education, Political Ecology, Migration, Gender, and Agriculture. Results showed that geographic research has focused on six major clusters during 2000-2019: GIS, Urban, Climate Change, Political Ecology, People, and Education. About 68.6 percent of …


Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee Dec 2021

Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee

Theses and Dissertations

Bioavailable phosphorus loads exported to Lake Michigan from the Milwaukee and Sheboygan River Watersheds appear to have increased in the last 40 years despite meeting total phosphorus (TP) loading goals set by the Great Lakes Water Quality Agreement (GLWQA).Overall, bioavailability of P delivered from the Milwaukee and Sheboygan Rivers was highest during the warmer months, which coincides with the nearshore nuisance algae growth season. However, first order loss rates of SRP calculated during baseflow recession were also greatest during the summer, suggesting that increased river residence time during the summer could reduce export of bioavailable P. Observations of phosphorus partitioning …


Characterizing Clustering Models Of High-Dimensional Remotely Sensed Data Using Subsampled Field-Subfield Spatial Cross-Validated Random Forests, Andrew B. Whetten Nov 2021

Characterizing Clustering Models Of High-Dimensional Remotely Sensed Data Using Subsampled Field-Subfield Spatial Cross-Validated Random Forests, Andrew B. Whetten

International Journal of Geospatial and Environmental Research

Clustering models are regularly used to construct meaningful groups of observations within complex datasets, and they are an exceptional tool for spatial exploratory analysis. The clusters detected in a recent spatio-temporal cluster analysis of leaf area index (LAI) in the Columbia River Basin (CRB) require further investigation since they are only derived using a single greenness metric. It is of great interest to further understand how greening indices can be used to determine separation of sites across an array of remotely sensed environmental attributes. In this prior work, there are highly localized minority clusters that were detected to be most …


The Spatial Patterns Of Pluvial Flood Risk, Blue-Green Infrastructure, And Social Vulnerability: A Case Study From Two Alaskan Cities, Arun K. Pallathadka, Heejun Chang, Idowu Ajibade Oct 2021

The Spatial Patterns Of Pluvial Flood Risk, Blue-Green Infrastructure, And Social Vulnerability: A Case Study From Two Alaskan Cities, Arun K. Pallathadka, Heejun Chang, Idowu Ajibade

International Journal of Geospatial and Environmental Research

Flooding is a serious form of natural hazard in Alaska, USA. Two of Alaska’s biggest cities, Anchorage and Fairbanks, have experienced flooding of varying magnitude since the cities were first settled in the early 20th century. Although flood mitigation measures such as blue-green infrastructure (BGI) are rising in prominence, the spatial relationship of BGI, urban pluvial flood (UPF) zone, and social vulnerability remains understudied. This study delineates the UPF zone of Anchorage and Fairbanks using the Blue Spot modeling and correlates it with the distribution of BGI at Census Block Group (CBG) scale, focusing on underlying social vulnerability using a …


Measuring Spatio-Temporal Responses To Hurricane Matthew Employing Twitgis, Seungil Yum Sep 2021

Measuring Spatio-Temporal Responses To Hurricane Matthew Employing Twitgis, Seungil Yum

International Journal of Geospatial and Environmental Research

This study explores spatio-temporal responses to Hurricane Matthew across the US states by analyzing Twitter data. This study finds that people in different states and periods respond differently to Hurricane Matthew. For instance, people in the Midwest and Northeast regions show a high proportion of tweets in the pre-hurricane period. Those in the Southeast region demonstrate a high proportion of those in the hurricane period, and those in the West region show a high proportion of those in the post-hurricane period. This study also finds that people increase long distance trips (over 100 km) and decrease short distance trips (within …


Transcriptomics And Toxcast Data Identify Bioeffects In Zebrafish Embryos Exposed To Chemical Mixtures In An Effluent-Dominated Stream, Emma Meade Aug 2021

Transcriptomics And Toxcast Data Identify Bioeffects In Zebrafish Embryos Exposed To Chemical Mixtures In An Effluent-Dominated Stream, Emma Meade

Theses and Dissertations

Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic organisms but also continually expose them to complex mixtures of pharmaceuticals and other contaminants of emerging concern (CECs) that can potentially impair growth, behavior, and reproduction. Limited toxicity data on the adverse biological impacts of in vivo exposure to these mixtures make it difficult to assess risk for aquatic organisms, particularly with respect to pharmaceuticals whose designed bioactivity often extends beyond conventionally monitored biological pathways. To address this knowledge gap, the goal of this thesis was to identify biomarkers of exposure to complex CEC mixtures relevant to specific chemicals …


Selection And Demography Drive Range-Wide Patterns Of Mhc Variation In Mule Deer (Odocoileus Hemionus), Rachel M. Cook Aug 2021

Selection And Demography Drive Range-Wide Patterns Of Mhc Variation In Mule Deer (Odocoileus Hemionus), Rachel M. Cook

Theses and Dissertations

Variation at functional genes involved in immune response is of increasing concern as wildlife diseases continue to emerge and threaten populations. The amount of standing genetic variation in a population is directly associated with its potential for rapid adaptation to novel environments. For genes in the major histocompatibility complex (MHC), which are crucial in activating the immune response and which have extremely high levels of polymorphism, the genetic variation has been shown to be influenced by both parasite-mediated selection and historical population demography. To better understand the relative roles of parasite-mediated selection and demography on MHC evolution in large populations, …


Geospatial Technology In Sustainable Cities And Communities: Introduction To The Special Issue, Siti Aekbal Salleh, Zulkiflee Abd Latif, Nazri Che Dom Jul 2021

Geospatial Technology In Sustainable Cities And Communities: Introduction To The Special Issue, Siti Aekbal Salleh, Zulkiflee Abd Latif, Nazri Che Dom

International Journal of Geospatial and Environmental Research

This special issue aims to demonstrate how we could leverage geospatial technology for sustainable cities and communities. Contributions on a wide range of geospatial technologies (e.g., GIS, remote sensing, spatial statistics, photogrammetry, and geomatics) as well as issues addressing better cities and communities for a sustainable future are encouraged. This issue contains selected papers from the 7th International Conference on Geomatics and Geospatial Technology (GGT) 2021, which took place in Kuala Lumpur, Malaysia, on 24th March 2021. The five articles selected for this special issue demonstrate how geospatial technology can be used to create more sustainable cities and communities. The …


Geological Lineament Assessment From Passive And Active Remote Sensing Imageries, Ainyyafiatty Arifin, Nor A. Adnan Jul 2021

Geological Lineament Assessment From Passive And Active Remote Sensing Imageries, Ainyyafiatty Arifin, Nor A. Adnan

International Journal of Geospatial and Environmental Research

Lineament is any extensive linear feature on the Earth’s surface that can be identified when there is a change in the topographical data. The advancement of technologies in remote sensing and Geographical Information Sciences (GIS) lead to the various studies and methods in mapping lineaments due to the availability of data from small to large scale areas. Lineament can be extracted from remote sensing data either with manual, semi-automatic or automatic image processing techniques that incorporate in numerous remote sensing and GIS software. Manually digitizing or tracing the aerial photograph is a subjective method as the lineament will be interpreted …


A Comparative Study Of Delineated Watersheds Using Aster And Srtm In Johor, Malaysia, Nafisah Khalid, Maisarah Abdul Halim, Siti Nur A’Tirah Shahimi Jun 2021

A Comparative Study Of Delineated Watersheds Using Aster And Srtm In Johor, Malaysia, Nafisah Khalid, Maisarah Abdul Halim, Siti Nur A’Tirah Shahimi

International Journal of Geospatial and Environmental Research

The availability of watershed delineation that has been generated from DEM data is difficult to obtain and the accessibility of DEM data which are unrestricted and precise are hard to obtain in Malaysia. The aim of this study is to examine the accuracy of watershed delineation between Digital Elevation Model (DEM) from ASTER and SRTM in Johor State Malaysia. In this study, free online data sources from USGS website are used to delineate watershed from ASTER and SRTM satellite imageries. The hydrological modelling tool namely ArcSWAT is utilized to delineate watersheds for both DEM datasets. Both DEM data that had …


Travel Time Patterns Of Students With Special Needs To Special Education Integrated Program-Based Schools In Johor Bahru, Malaysia: An Initial Finding, Nurul Hawani Idris, Nur Afiqah Ahmad Bakhtiar, Mohamad Hafis Izran Ishak May 2021

Travel Time Patterns Of Students With Special Needs To Special Education Integrated Program-Based Schools In Johor Bahru, Malaysia: An Initial Finding, Nurul Hawani Idris, Nur Afiqah Ahmad Bakhtiar, Mohamad Hafis Izran Ishak

International Journal of Geospatial and Environmental Research

Education for all has been a global priority to ensure that all students have equal access to high-quality education regardless of disability or minority status. In Malaysia, the special education integrated programme (SEIP) is designed to close the inequality gap by integrating special education into existing government and vernacular schools. Numerous studies examine the travel patterns of regular students to school, resulting in a dearth of research on the travel patterns of special needs students to formal school. Thus, this paper uses spatial analysis to demonstrate the travel patterns of students with special needs to SEIP schools. This paper demonstrated …


Geospatial Clustering And Hot Spot Detection Of Covid-19 Incidence In 2020: A Global Analysis, Munazza Fatima, Sana Arshad, Ibtisam Butt, Saba Arshad May 2021

Geospatial Clustering And Hot Spot Detection Of Covid-19 Incidence In 2020: A Global Analysis, Munazza Fatima, Sana Arshad, Ibtisam Butt, Saba Arshad

International Journal of Geospatial and Environmental Research

Emergence and spread of Covid-19 initiated diversified researches based on spatial analysis in visualization, exploration, and modelling of this infection. This short communication is an attempt to comprehend the geographic distribution and spatial clustering of Covid-19 in year 2020. Main objective is to spatially analyze Covid-19 incidence rates, identification of hotspots and clusters outliers at global level. Monthly data of reported cases were taken from World Health Organization dashboard and situation reports. Incidence rate was calculated for each country for each month. Spatial autocorrelation techniques of Global Moran are I and Anselian Local Moran’s I were used to examine the …


The Flow Less Traveled: Documenting Independent Original Research On Fluid Flow Interactions In The Laurentian Great Lakes And Immediate Surroundings, Thomas F. Hansen May 2021

The Flow Less Traveled: Documenting Independent Original Research On Fluid Flow Interactions In The Laurentian Great Lakes And Immediate Surroundings, Thomas F. Hansen

Theses and Dissertations

This work is a compilation of several research projects undertaken by the author. Each research effort identifies a problem that has been addressed traditionally using methods that are significantly costly, to such an extent that, in general, funding, convenience, and practicality are primary limiting factors to their effective implementation. In each case, the author has been able to either build upon existing, less expensive alternatives, or even invent novel approaches. The fundamental recurring research question is, can creative, even novel, computational approaches make more efficient use of resources to interpret or present data in such a way as to make …


Molecular Weight Distributions And Size-Dependent Composition Of Dissolved Organic Matter In The Aquatic Continuum, Hui Lin May 2021

Molecular Weight Distributions And Size-Dependent Composition Of Dissolved Organic Matter In The Aquatic Continuum, Hui Lin

Theses and Dissertations

Dissolved organic matter (DOM) in aquatic environments is one of the most important carbon reservoirs in global carbon cycling. The molecular weight of DOM is strongly related to a great number of biogeochemical reactions, influencing ecological functions and the fate of bioactive elements in aquatic ecosystems. A new technique coupling flow field-flow fractionation with fluorescence excitation-emission matrix (EEM) and parallel factor (PARAFAC) analysis was developed to elucidate the variations in DOM composition and optical properties with molecular weight in the individual samples and their changes along the aquatic continuum. Based on the novel coupling technique, variations in DOM characteristics were …


Health Goals For Perfluorinated Alkyl Substances (Pfas): A Review Of Branched Isomers, The Role Of Industrial Sources, And The Implications Of Pfas In Biosolids On End-Of-Life Disposal Methods, Katarina Schulz May 2021

Health Goals For Perfluorinated Alkyl Substances (Pfas): A Review Of Branched Isomers, The Role Of Industrial Sources, And The Implications Of Pfas In Biosolids On End-Of-Life Disposal Methods, Katarina Schulz

Theses and Dissertations

Per- and polyfluorinated alkyl substances, or PFAS, have been used for over half a century, but have become an emerging contaminant of significant concern due to their newly found widespread occurrence and recalcitrance in the environment, their tendency to bioaccumulate, and the health effects now associated with a very low level of exposure. Many gaps in knowledge remain about the fate of these chemicals in the environment and the extent of their impacts on biota. This thesis aims to fill some of the recognized gaps in knowledge: differences between linear and branched isomers of PFAS, predicting the presence of PFAS …


Application Of Deep Learning For Imaging-Based Stream Gaging, Ryan Lee Vanden Boomen May 2021

Application Of Deep Learning For Imaging-Based Stream Gaging, Ryan Lee Vanden Boomen

Theses and Dissertations

In the field of water resources management, one vital instrument utilized is the stream gage. Stream gages monitor and record flow and water height within some water body. The United States Geological Survey maintains a network of stream gages at many locations across the country. Many of these sites are also equipped with webcams monitoring the state of the water body at the moment of measurement. Previous studies have outlined methods to approximate stream gage data remotely with limitations such as the requirement of detailed depth information for each site. This study seeks to create a process for training a …


Bottom-Up Understanding Of Informal Settlements: Perspectives Of Urban Slum Dwellers In Nima, Ghana., Bernard Apeku May 2021

Bottom-Up Understanding Of Informal Settlements: Perspectives Of Urban Slum Dwellers In Nima, Ghana., Bernard Apeku

Theses and Dissertations

More than a quarter of the world’s population lives in informal settlements which house a rapidly growing proportion of the inhabitants of cities in sub-Saharan Africa, such as Accra, Ghana, and in the Global South more generally. However, scholars have shown that the urban planning and urban redevelopment strategies that affect these settlements are top-down in character with minimal resident participation. These prevailing planning and redevelopment strategies are based on the outsiders’ perceptions of informal neighborhoods, rendering them quite inefficient. Therefore, to develop workable policies and strategies that will improve the living condition of informal urban settlers, it is important …