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Full-Text Articles in Civil and Environmental Engineering

Pectin Modified Metal Nanoparticles And Their Application In Property Modification Of Biosensors, Meena Nemiwal, Tian C. Zhang, Dinesh Kumar Jan 2021

Pectin Modified Metal Nanoparticles And Their Application In Property Modification Of Biosensors, Meena Nemiwal, Tian C. Zhang, Dinesh Kumar

Department of Civil and Environmental Engineering: Faculty Publications

Pectin is a structural anionic heteropolysaccharide and abundantly found in the cell wall of terrestrial trees and plants. It exhibits several advantageous properties such as non-toxicity, cheap, biodegradable, biocompatible, abundant, flexible, etc. Functional groups like carboxylic acid and hydroxyl make pectin suitable to be covalently bonded with other biomolecules and proteins. Based on these properties, pectin is being extensively employed to encapsulate/coat metal nanoparticles (MNPs) to inhibit their aggregation and enhancing the suitability of MNPs for a wide range of applications in healthcare like drug delivery, antimicrobial activity, antioxidant etc. Another important application of pectin is to enhance the electrochemical …


Single-Step Hydrothermal Synthesis Of Biochar From H3po4-Activated Lettucewaste For Efficient Adsorption Of Cd(Ii) In Aqueous Solution, Quyun Chen, Tian C. Zhang, Like Ouyang, Shaojun Yuan Jan 2021

Single-Step Hydrothermal Synthesis Of Biochar From H3po4-Activated Lettucewaste For Efficient Adsorption Of Cd(Ii) In Aqueous Solution, Quyun Chen, Tian C. Zhang, Like Ouyang, Shaojun Yuan

Department of Civil and Environmental Engineering: Faculty Publications

Developing an ideal and cheap adsorbent for adsorbing heavy metals from aqueous solution has been urgently need. In this study, a novel, effective and low-cost method was developed to prepare the biochar from lettuce waste with H3PO4 as an acidic activation agent at a low-temperature (circa 200°C) hydrothermal carbonization process. A batch adsorption experiment demonstrated that the biochar reaches the adsorption equilibrium within 30 min, and the optimal adsorption capacity of Cd(II) is 195.8 mg⋅g-1at solution pH 6.0, which is significantly improved from circa 20.5 mg⋅g-1 of the original biochar without activator. The fitting …


Combining Electrochemical Nitrate Reduction And Anammox For Treatment Of Nitrate-Rich Wastewater: A Short Review, Xinyi Zou, Chongjun Chen, Changhong Wang, Qun Zhang, Zhuowei Yu, Haiping Wu, Chao Zhuo, Tian C. Zhang Jan 2021

Combining Electrochemical Nitrate Reduction And Anammox For Treatment Of Nitrate-Rich Wastewater: A Short Review, Xinyi Zou, Chongjun Chen, Changhong Wang, Qun Zhang, Zhuowei Yu, Haiping Wu, Chao Zhuo, Tian C. Zhang

Department of Civil and Environmental Engineering: Faculty Publications

Treatment of nitrate-rich wastewater is important but challenging for the conventional biological denitrification process. Here, we propose combining the electrochemical reduction and anaerobic ammonium oxidation (anammox) processes together for treatment of nitrate-rich wastewater. This article reviews the mechanism and current research status of electrochemical reduction of nitrate to ammonium as well as the mechanism and applicability of the anammox process. This article discusses the principles, superiorities, and challenges of this combined process. The feasibility of the combined process depends on the efficiency of electrochemical nitrate reduction to ammonium and the conditions in the anammox process to use the reduced ammonium …


A Framework For Achieving Sustainability By Overcoming The Challenges Of The Construction Supply Chain During The Design Process, Ayman Ahmed Ezzat Othman, Nooran Alnassar Jan 2021

A Framework For Achieving Sustainability By Overcoming The Challenges Of The Construction Supply Chain During The Design Process, Ayman Ahmed Ezzat Othman, Nooran Alnassar

Architectural Engineering

This paper aims to develop a framework to achieve sustainability by overcoming the challenges of the construction supply chain (CCSC) during the design process. To achieve this, two approaches, namely theoretical and practical, were used to accomplish four objectives. For the theoretical approach, based on literature review and case studies, the objective used was to identify, classify and validate the challenges that the construction supply chain (CSC) encounter. For the practical approach, a survey questionnaire was employed to quantify the CCSC and investigate the perception of architectural design firms (ADFs) in Egypt towards achieving sustainability by overcoming the CCSC during …


Chlorination As Drinking Water Disinfection Technique And Disinfection By Products: A Scientometric Analysis, Sapna Ramchandra Shinde, Sayali D. Apte Dr, Kanchan C. Khare Dr, Philipp Otter Mr Jan 2021

Chlorination As Drinking Water Disinfection Technique And Disinfection By Products: A Scientometric Analysis, Sapna Ramchandra Shinde, Sayali D. Apte Dr, Kanchan C. Khare Dr, Philipp Otter Mr

Library Philosophy and Practice (e-journal)

The Sustainable Development Goals (SDG) 2015, defined to achieve a better and more sustainable future, contains goal number 6 related to safe and affordable drinking water facility for all till 2030. The rural and remote areas in the developing countries predominantly face the scarcity of pathogen free drinking water leading to water borne diseases and deaths due to consumption of contaminated water indicating a need of advancement in the drinking water disinfection techniques. The paper discusses scientometric analysis of publication trends in chlorination as a popular disinfection techniques and research related to the Disinfection By Products (DBPs) that are produced …


Nanomaterials In The Environment, Human Exposure Pathway, And Health Effects: A Review, Arindam Malakar, Sushil R. Kanel, Chittaranjan Ray, Daniel D. Snow, Mallikarjuna N. Nadagouda Jan 2021

Nanomaterials In The Environment, Human Exposure Pathway, And Health Effects: A Review, Arindam Malakar, Sushil R. Kanel, Chittaranjan Ray, Daniel D. Snow, Mallikarjuna N. Nadagouda

Daugherty Water for Food Global Institute: Faculty Publications

Nanomaterials (NMs), both natural and synthetic, are produced, transformed, and exported into our environment daily. Natural NMs annual flux to the environment is around 97% of the total and is significantly higher than synthetic NMs. However, synthetic NMs are considered to have a detrimental effect on the environment. The extensive usage of synthetic NMs in different fields, including chemical, engineering, electronics, and medicine, makes them susceptible to be discharged into the atmosphere, various water sources, soil, and landfill waste. As ever-larger quantities of NMs end up in our environment and start interacting with the biota, it is crucial to understand …


Baseflow Nitrate Dynamics Within Nested Watersheds Of An Agricultural Stream In Nebraska, Usa, Galen Richards, Troy E. Gilmore, Aaron R. Mittelstet, Tiffany Messer, Daniel D. Snow Jan 2021

Baseflow Nitrate Dynamics Within Nested Watersheds Of An Agricultural Stream In Nebraska, Usa, Galen Richards, Troy E. Gilmore, Aaron R. Mittelstet, Tiffany Messer, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

There is a need to evaluate high surface nitrate concentrations across agricultural watersheds, both spatially and temporally, to increase understanding of source and timing of nitrogen loads in streams and rivers. Bazile Creek is a high-nitrate stream originating in the agriculturally intensive Bazile Groundwater Management Area of Eastern Nebraska, USA. It is a gaining stream that receives groundwater with high nitrate concentrations originating from nonpoint sources. The objective of this study was to determine spatial and temporal variability of baseflow nitrate concentrations in Bazile Creek and its tributaries and to relate this variability to watershed characteristics. Surface-water nitrate samples were …


Surveillance Of Plasticizers, Bisphenol A, Steroids And Caffeine In Surface Water Of River Ganga And Sundarban Wetland Along The Bay Of Bengal: Occurrence, Sources, Estrogenicity Screening And Ecotoxicological Risk Assessment, Paromita Chakraborty, Nancy W. Shappell, Moitraiyee Mukhopadhyay, Sathaporn Onanong, Daniel D. Snow Jan 2021

Surveillance Of Plasticizers, Bisphenol A, Steroids And Caffeine In Surface Water Of River Ganga And Sundarban Wetland Along The Bay Of Bengal: Occurrence, Sources, Estrogenicity Screening And Ecotoxicological Risk Assessment, Paromita Chakraborty, Nancy W. Shappell, Moitraiyee Mukhopadhyay, Sathaporn Onanong, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

The transboundary River Ganga serves as a conduit for meltwater from the Himalayas and is a major freshwater source for two thirds of Indian population before emptying into the Sundarban Delta, the largest estuary in the Bay of Bengal. Endocrine disrupting compounds (EDCs) such as phthalic acid esters (PAEs) and bisphenol A (BPA) used as organic plastic additives can pollute the aquatic environment receiving plastic litter. Hence, we have investigated these EDCs in water samples from Ganga and Sundarban wetland of India. Since these compounds exhibit estrogenic potential, we have further measured steroids and evaluated the estrogenic activity (estradiol equivalents, …


Transmission Routes Of The Microbiome And Resistome From Manure To Soil And Lettuce, Yuepeng Sun, Daniel D. Snow, Harkamal Walia, Xu Li Jan 2021

Transmission Routes Of The Microbiome And Resistome From Manure To Soil And Lettuce, Yuepeng Sun, Daniel D. Snow, Harkamal Walia, Xu Li

Daugherty Water for Food Global Institute: Faculty Publications

The land application of animal manure can introduce manure microbiome and resistome to croplands where food crops are grown. The objective of this study was to characterize the microbiome and resistome on and in the leaves of lettuce grown in manured soil and identify the main transmission routes of microbes and antibiotic resistance genes (ARGs) from soil to the episphere and endosphere of lettuce. Shotgun metagenomic results show that manure application significantly altered the composition of the microbiome and resistome of surface soil. SourceTracker analyses indicate that manure and original soil were the main source of the microbiome and resistome …


Low-Level Groundwater Atrazine In High Atrazine Usage Nebraska Counties: Likely Effects Of Excessive Groundwater Abstraction, Moses New-Aaron, Olufemi Abimbola, Raheleh Mohammadi, Oluwaseun Famojuro, Zaeema Naveed, Azar Abadi, Jesse E. Bell, Shannon Bartelt-Hunt, Eleanor G. Rogan Jan 2021

Low-Level Groundwater Atrazine In High Atrazine Usage Nebraska Counties: Likely Effects Of Excessive Groundwater Abstraction, Moses New-Aaron, Olufemi Abimbola, Raheleh Mohammadi, Oluwaseun Famojuro, Zaeema Naveed, Azar Abadi, Jesse E. Bell, Shannon Bartelt-Hunt, Eleanor G. Rogan

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Recent studies observed a correlation between estrogen-related cancers and groundwater atrazine in eastern Nebraska counties. However, the mechanisms of human exposure to atrazine are unclear because low groundwater atrazine concentration was observed in counties with high cancer incidence despite having the highest atrazine usage. We studied groundwater atrazine fate in high atrazine usage Nebraska counties. Data were collected from Quality Assessed Agrichemical Contaminant Nebraska Groundwater, Parameter–Elevation Regressions on Independent Slopes Model (PRISM), and water use databases. Descriptive statistics and cluster analysis were performed. Domestic wells (59%) were the predominant well type. Groundwater atrazine was affected by well depth. Clusters consisting …


Improvements In Sub-Catchment Fractional Snowpack And Snowmelt Parameterizations And Hydrologic Modeling For Climate Change Assessments In The Western Himalayas, Vishal Singh, Francisco Muñoz-Arriola Jan 2021

Improvements In Sub-Catchment Fractional Snowpack And Snowmelt Parameterizations And Hydrologic Modeling For Climate Change Assessments In The Western Himalayas, Vishal Singh, Francisco Muñoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The present work proposes to improve estimates of snowpack and snowmelt and their assessment in the steep Himalayan ranges at the sub-catchment scale. Temporal variability of streamflow and the associated distribution of accumulated snow in catchments with glacier presence in the Himalayas illustrates how changes in snowpack and snowmelt can affect the water supply for local water management. The primary objective of this study is to assess the role of elevation, temperature lapse rate (TLR), and precipitation lapse rate (PLR) in the computation of snowpack (or snowfall) and snowmelt in sub-catchments of the Satluj River basin. Modeling of snowpack and …


Opportunistic Maintenance Strategy Of A Heave Compensation System For Expected Performance Degradation, Chao Zhang, Yujie Qian, Hongyan Dui, Shaoping Wang, Rentong Chen, Mileta M. Tomovic Jan 2021

Opportunistic Maintenance Strategy Of A Heave Compensation System For Expected Performance Degradation, Chao Zhang, Yujie Qian, Hongyan Dui, Shaoping Wang, Rentong Chen, Mileta M. Tomovic

Engineering Technology Faculty Publications

In the marine industry, heave compensation systems are applied to marine equipment to compensate for the adverse effects of waves and the hydraulic system is usually used as the power system of heave compensation systems. This article introduces importance theory to the opportunistic maintenance (OM) strategy to provide guidance for the maintenance of heave compensation systems. The working principle of a semi-active heave compensation system and the specific working states of its hydraulic components are also first explained. Opportunistic maintenance is applied to the semi-active heave compensation system. Moreover, the joint integrated importance measure (JIIM) between different components at different …


Analyzing Freight Congestion And Transportation Performance Measures Using The National Performance Management Research Data Set (Npmrds), Yaxin Zhang Jan 2021

Analyzing Freight Congestion And Transportation Performance Measures Using The National Performance Management Research Data Set (Npmrds), Yaxin Zhang

Dissertations and Theses

Traffic congestion is common in urban areas. It results in loss of productivity, increased risk of passenger safety, increased fuel consumption, environment pollution, etc. Improving performance measurement is a tool to improve traffic flow and capacity planning.

The main data source in this research is the National Performance Management Research Data Set (NPMRDS) for 2018. NPMRDS is a form of commercial GPS probe data, obtained from vehicles with on-board probe technologies. This dataset is licensed by the Federal Highway Administration and is made available to State Departments of Transportation (DOTs) and Metropolitan Planning Organizations (MPOs) for the purpose of federally …


Alternate Load Paths And Retrofits For Long-Span Truss Bridges Under Sudden Member Loss And Blast Loads, Huihui Li Jan 2021

Alternate Load Paths And Retrofits For Long-Span Truss Bridges Under Sudden Member Loss And Blast Loads, Huihui Li

Dissertations and Theses

In current bridge design practices, due to the existence of alternate load paths (ALPs), continued stability and progressive collapse-resistance of long-span bridges following the initialed loss of a critical member can be attributed to “redundancy”. However, “redundancy”, also indicated as the post member failure behavior of long-span bridges is not well understood and is not explicitly considered, especially for long-span truss bridges. As one of the most famous collapse events that took place recently, collapse of the I-35W truss bridge has demonstrated the vulnerabilities of long-span truss bridges, and their societal and economic consequences under the abnormal events, such as …


Dynamics Of Simultaneous Nitrite Ion And Ammonia Chlorination In Complex Water Quality Matrices And Their Impact On Chlorine Residual Speciation During Disinfection, Shirin Estahbanati Jan 2021

Dynamics Of Simultaneous Nitrite Ion And Ammonia Chlorination In Complex Water Quality Matrices And Their Impact On Chlorine Residual Speciation During Disinfection, Shirin Estahbanati

Dissertations and Theses

Although chlorination of ammonia and nitrite ions have been studied comprehensively, the kinetics of chlorination in water matrices containing ammonia in the presence of nitrite ion have not been fully understood. The coexistence of the two nitrogen compounds is a phenomenon most often encountered during biological nitrification of municipal wastewaters. The spatial variation of the nitrogen species generates unpredictable complications in the effectiveness of chlorination as the disinfection process. The focus of the research study was the examination of chlorine residual speciation and the fate of ionic nitrogen species, i.e. nitrite and nitrate ions, under various experimental conditions. The experimental …


Structural Robustness Of Long-Span Cable-Supported Bridges, Qian Chen Jan 2021

Structural Robustness Of Long-Span Cable-Supported Bridges, Qian Chen

Dissertations and Theses

As a critical part of the current infrastructure system, long-span bridges are directly exposed to adverse environments, such as floods, scours, hurricanes, etc., and dynamic loads such as earthquakes and vehicular impacts. Additionally, recent long-span cable-supported collapse examples show that many bridges suffered progressive collapse when local damage occurred, and they are highly vulnerable to severe damages in the event of a localized failure. However, the traditional design approaches are unable to provide explicit measures of residual safety of bridges, especially after an abnormal event. Currently available redundancy and robustness evaluation approaches, which were developed mainly for short-span bridges, are …


Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang Jan 2021

Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang

Dissertations and Theses

The contemporary hydrosystems of the United States involve a complex combination of natural and modified basins in the presence of changing climate and anthropogenic impacts. An enhanced understanding of the interdependence between climate forcings, human-induced interventions, and water balance in both natural and modified basins are essential for developing reliable and resilient hydrosystems and for better water resources management. In response, this dissertation focuses on investigating the hydroclimatology of natural and modified basins across the contiguous United States. It has three research objectives: (1) to explain flow alterations due to anthropogenic activities, especially dam operations, in modified basins and understand …


Exploring The Use Of Drones For Conducting Traffic Mobility And Safety Studies, Abdallah N. Kinero Jan 2021

Exploring The Use Of Drones For Conducting Traffic Mobility And Safety Studies, Abdallah N. Kinero

UNF Graduate Theses and Dissertations

ABSTRACT

Advanced traffic data collection methods, including the application of aerial sensors (drones) as traffic data collectors, can provide real-time traffic information more efficiently, effectively, and safely than traditional methods. Traffic trajectory data like vehicles’ coordinates and point timestamps are challenging to obtain at intersections using traditional field survey methods. The coordinates and timestamps crucial in calculating trajectories can be obtained using drones and their particular integrated software. Thus, this study explores the use of unmanned aerial systems (UAS), particularly tethered drones, to obtain traffic parameters for traffic mobility and safety studies at an unsignalized intersection in Tallahassee, Florida. Tethered …


Estimating A Range Of Flow Rates Resulting From Extreme Storm Events Within The Wekiva River Watershed Through Statistical Testing And Modeling, Wesley K. Koning Jan 2021

Estimating A Range Of Flow Rates Resulting From Extreme Storm Events Within The Wekiva River Watershed Through Statistical Testing And Modeling, Wesley K. Koning

UNF Graduate Theses and Dissertations

The middle portion of the St. Johns River is located in East-Central Florida, USA. This region of the St. Johns River is increasingly subject to urbanization and conversion of forest areas to agricultural land. Overall, these changes mean that future flood events in the area could adversely impact local citizens. Therefore, the examination of extreme flood events and resiliency to such events is critical. The purpose of this preliminary study is to explore a range of practical applications to estimate extreme flood flows at watercourses within the Middle St. Johns River Basin, focusing specifically upon the Wekiva River sub-basin. The …


The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, S. A. Talke, Ramin Familkhalili, D. A. Jay Jan 2021

The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, S. A. Talke, Ramin Familkhalili, D. A. Jay

Civil & Environmental Engineering Faculty Publications

We combine archival research, semi-analytical models, and numerical simulations to address the following question: how do changes to channel geometry alter tidal properties and flood dynamics in a hyposynchronous, strongly frictional estuary with a landward decay in tidal amplitudes? Records in the Saint Johns River Estuary since the 1890s show that tidal range has doubled in Jacksonville, Florida. Near the estuary inlet, tidal discharge approximately doubled but tidal amplitudes increased only ∼6%. Modeling shows that increased shipping channel depths from ∼5 to ∼13m drove the observed changes, with other factors like channel shortening and width reduction producing comparatively minor effects. …


Online Bus Speed Prediction With Spatiotemporal Interaction: A Laplace Approximation-Based Bayesian Approach, Haipeng Cui, Kun Xie, Bin Hu, Hangfei Lin Jan 2021

Online Bus Speed Prediction With Spatiotemporal Interaction: A Laplace Approximation-Based Bayesian Approach, Haipeng Cui, Kun Xie, Bin Hu, Hangfei Lin

Civil & Environmental Engineering Faculty Publications

This study proposes a novel Bayesian hierarchical approach for online bus speed prediction by explicitly accounting for the spatiotemporal interaction (STI) of speed observations. The use of Laplace approximation can expedite the estimation of Bayesian models and enable the implementation of online prediction. Large numbers of trials are carried out to identify significant predictors and the optimal length of the look-back time window to achieve the highest prediction accuracy. The spatiotemporal interacting patterns are also explored, and results show that the Type IV model assuming the structured spatial effect interacts with the structured temporal effect can best accommodate the bus …


Laboratory Study Of The Effects Of Flexible Vegetation On Solute Diffusion In Unidirectional Flow, Sha Lou, Hao Wang, Hongzhe Liu, Guihui Zhong, Larisa Dorzhievna Radnaeva, Elena Nikitina, Gangfeng Ma, Shuguang Liu Jan 2021

Laboratory Study Of The Effects Of Flexible Vegetation On Solute Diffusion In Unidirectional Flow, Sha Lou, Hao Wang, Hongzhe Liu, Guihui Zhong, Larisa Dorzhievna Radnaeva, Elena Nikitina, Gangfeng Ma, Shuguang Liu

Civil & Environmental Engineering Faculty Publications

Background

Flexible vegetation is an important part of the riverine ecosystem, which can reduce flow velocity, change turbulence structure, and affect the processes of solute transport. Compared with the flow with rigid vegetation, which has been reported in many previous studies, bending of flexible vegetation increases the complexity of the flow-vegetation-solute interactions. In this study, laboratory experiments are carried out to investigate the influence of flexible vegetation on solute transport, and methods for estimating the lateral and longitudinal diffusion coefficients in the rigid vegetated flow are examined for their applications to the flow with flexible vegetation.

Results

The experimental observations …


Save-T: Safety Analysis Visualization And Evaluation Tool, Yuan Zhu, Sami Demiroluk, Kaan Ozbay, Kun Xie, Hong Yang, Di Sha Jan 2021

Save-T: Safety Analysis Visualization And Evaluation Tool, Yuan Zhu, Sami Demiroluk, Kaan Ozbay, Kun Xie, Hong Yang, Di Sha

Civil & Environmental Engineering Faculty Publications

Traffic crashes are one of the biggest issues which constitute a threat to lives of the motorists and disrupt operations of the transportation system. To reduce the number of crashes and alleviate their impacts, it is necessary to scrutinize the factors contributing to the risk of traffic crashes. Lately, visual analytics tools become very popular for data exploration and obtaining insights from the data. In this paper, a new web-based data visualization tool called Safety Analysis Visualization and Evaluation Tool (SAVE-T) was introduced. This tool enables users to interactively create queries and visually explore the results. By utilizing an online …


Investigation Of Anaerobic Digestion Of The Aqueous Phase From Hydrothermal Carbonization Of Mixed Municipal Solid Waste, Kameron J. Adams, Ben Stuart, Sandeep Kumar Jan 2021

Investigation Of Anaerobic Digestion Of The Aqueous Phase From Hydrothermal Carbonization Of Mixed Municipal Solid Waste, Kameron J. Adams, Ben Stuart, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

In 2017, the United States Environmental Protection Agency (EPA) reported that Americans generated over 268 million tons of municipal solid waste (MSW). The majority (52%) of this waste ends up in landfills, which are the third largest source of anthropogenic methane emissions. Improvements in terms of waste management and energy production could be solved by integrating MSW processing with hydrothermal carbonization (HTC) and anaerobic digestion (AD) for converting organic carbon of MSW to fuels. The objectives of this study were to (a) investigate HTC experiments at varying temperatures and residence times (b) evaluate aqueous phase and solids properties, and (c) …


Wave Climate Associated With Changing Water Level And Ice Cover In Lake Michigan, Chenfu Huang, Longhuan Zhu, Gangfeng Ma, Guy A. Meadows, Pengfei Xue Jan 2021

Wave Climate Associated With Changing Water Level And Ice Cover In Lake Michigan, Chenfu Huang, Longhuan Zhu, Gangfeng Ma, Guy A. Meadows, Pengfei Xue

Civil & Environmental Engineering Faculty Publications

Detailed knowledge of wave climate change is essential for understanding coastal geomorphological processes, ecosystem resilience, the design of offshore and coastal engineering structures and aquaculture systems. In Lake Michigan, the in-situ wave observations suitable for long-term analysis are limited to two offshore MetOcean buoys. Since this distribution is inadequate to fully represent spatial patterns of wave climate across the lake, a series of high-resolution SWAN model simulations were performed for the analysis of long-term wave climate change for the entirety of Lake Michigan from 1979 to 2020. Model results were validated against observations from two offshore buoys and 16 coastal …


Characterizing Seagrass Effects On Hydrodynamics Of Waves And Currents Through Field Measurements And Computational Modelling, Ramin Familkhalili, Navid Tahvildari Jan 2021

Characterizing Seagrass Effects On Hydrodynamics Of Waves And Currents Through Field Measurements And Computational Modelling, Ramin Familkhalili, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

Low-lying coastal and estuarine areas are among the most populated regions globally, have high economic significance, and are increasingly threatened by climate change, sea level rise, nuisance flooding, and extreme storms. Nature-based coastal protections are sustainable and sea-level resilient alternatives compared to traditional solutions such as dikes and seawalls. Submerged aquatic vegetation (SAV) or seagrasses can provide coastal flood and erosion protection by attenuating storm wave and current energy and stabilizing seabed sediments. However, more research is needed to understand the interactions between flow, SAVs, and sediments. These dynamic interactions affect flow at different scales and seagrass productivity. In this …


Effects Of Hydrological And Climatic Variables On Cyanobacterial Blooms In Four Large Shallow Lakes Fed By The Yangtze River, Jian Huang, Qiujin Xu, Xixi Wang, Hao Ji, Edward J. Quigley, Mohamadali Sharbatmaleki, Simeng Li, Beidou Xi, Biao Sun, Caole Li Jan 2021

Effects Of Hydrological And Climatic Variables On Cyanobacterial Blooms In Four Large Shallow Lakes Fed By The Yangtze River, Jian Huang, Qiujin Xu, Xixi Wang, Hao Ji, Edward J. Quigley, Mohamadali Sharbatmaleki, Simeng Li, Beidou Xi, Biao Sun, Caole Li

Civil & Environmental Engineering Faculty Publications

Shallow lakes, one of the most widespread water bodies in the world, are easily shifted to a new trophic state due to external interferences. Shifting hydrologic conditions and climate change can cause cyanobacterial harmful algal blooms (CyanoHABs) in shallow lakes, which pose serious threats to ecological integrity and human health. This study analyzed the effects of hydrologic and meteorological variables on cyanobacterial blooms in Yangtze-connected lakes (Lake Dongting and Poyang) and isolated lakes (Lake Chao and Tai). The results show that (i) chlorophyll-a (Chl-a) concentration tends to decrease exponentially with increasing relative lake level fluctuations (RLLF) and precipitation, but to …


Land Use And Land Cover Classifications Of Horqin Sandy Land Dune-Meadow Areas, Wenmei Cao, Tingxi Liu, Xixi Wang, Guanli Wang, Dongfang Li, Xing Tong Jan 2021

Land Use And Land Cover Classifications Of Horqin Sandy Land Dune-Meadow Areas, Wenmei Cao, Tingxi Liu, Xixi Wang, Guanli Wang, Dongfang Li, Xing Tong

Civil & Environmental Engineering Faculty Publications

In this study, we determine land use/land cover (LULC) types using only optical remote sensing data in a dune-meadow area of Horqin Sandy Land in northeast China. We used 64 Sentinel-2 remote sensing images from 2018. An LULC decision tree recognition rule was established by combining image segmentation technology, vegetation phenology information, and habitat characteristics. The overall classification accuracy was 0.91, and the Kappa coefficient was 0.89. The classification results show that most of the study region was dryland area, accounting for 33.79%, followed by shrub communities at 25.03%. High-diversity semi-shrub communities and arbor forests accounted for 14.54% and 10%, …


Linear Generators In Wave Energy Conversion: Performance, Feasibility, And Location Study, Luis Fernandez De Valderrama Jan 2021

Linear Generators In Wave Energy Conversion: Performance, Feasibility, And Location Study, Luis Fernandez De Valderrama

UNF Graduate Theses and Dissertations

As the energy demand increases and climate change becomes a major problem, the solution to decrease greenhouse gas emissions and mitigate the effects of climate change involves increasing the use of sustainable and renewable sources to generate electricity. However, developed renewable sources have inconveniences that make them incapable of generating the totality of the electricity that a country demands. Wave energy is an alternative renewable energy source that can help mitigate the inconveniences of other renewable sources and decrease the emission of greenhouse gases.

This study aims to find the potential of linear generators in wave energy by analyzing the …


Determination Of Extreme Flood Events In The Black Creek, Julington Creek, Dubin Creek, Big Davis Creek, Ortega River, And Pablo Creek Sub-Basins Of The Lower St. Johns River Basin, Florida, Usa, Samantha Kovalenko Jan 2021

Determination Of Extreme Flood Events In The Black Creek, Julington Creek, Dubin Creek, Big Davis Creek, Ortega River, And Pablo Creek Sub-Basins Of The Lower St. Johns River Basin, Florida, Usa, Samantha Kovalenko

UNF Graduate Theses and Dissertations

Extreme flood estimation is a continuously developing field of research. Economic and community well-being are dependent on flood risk preventative planning, which can only be successfully implemented through sound flood estimating methods. Without the execution of proper flood prevention measures, many communities remain at risk. In addition to a new extreme flood estimation methodology, this research presents a new approach to establish flood estimates. Traditionally, more than one flood estimate per return frequency storm does not exist. This research produced a set of 10-, 25-, 50-, and 100-year flood estimates for the Black Creek, Julington Creek, Durbin Creek, Big Davis …