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Full-Text Articles in Civil and Environmental Engineering

Geo-Spatial Mapping As A Catalyst For Creative And Engaged Design In Engineering Education, Jessie Zarazaga Apr 2019

Geo-Spatial Mapping As A Catalyst For Creative And Engaged Design In Engineering Education, Jessie Zarazaga

Multidisciplinary Studies Theses and Dissertations

Exploiting the technology of geo-spatial mapping student designers can develop deep understandings of the rich and layered data of a spatial context, a situational understanding essential to responsible civic design. However the actions inherent in the construction of spatial data armatures can simultaneously be harnessed as creative strategies, in which mapping processes become the context for generative spatial play. The ambition of this study is to propose efficient pedagogic structures to help prepare civil and environmental student engineers to be not only strong participants, but leaders, in the design of the built environment. The interpretation of site data, mapped as …


Latent Choice Models To Account For Misclassification Errors In Discrete Transportation Data, Lacramioara Elena Balan Apr 2019

Latent Choice Models To Account For Misclassification Errors In Discrete Transportation Data, Lacramioara Elena Balan

Civil & Environmental Engineering Theses & Dissertations

One of the most fundamental tasks when it comes to analyzing data using statistical methods is to understand the relationship between the explanatory variables and the outcome. Misclassification of explanatory variables is a common risk when using statistical modeling techniques. In this dissertation, we define ‘misclassification,’ as a response that is reported or recorded in the wrong category; for example, a variable is registered as a one when it should have the value zero. Misclassification can easily happen in any data; for example, in an interview setting where the respondent misunderstands the question or the interviewer checks the wrong box. …


Austere Location Wind Turbine Energy System Analysis, Lukas Cowen, Douglas S. Dudis, Torrey J. Wagner Apr 2019

Austere Location Wind Turbine Energy System Analysis, Lukas Cowen, Douglas S. Dudis, Torrey J. Wagner

Faculty Publications

One promising technology to combat an energy shortage in austere locations is wind energy. In combination with battery storage and generator backup, we explore the feasibility of using a hybrid energy system to reduce the volume of diesel fuel required. Modeling the energy demands in austere locations will enable missions in remote settings to optimize their energy costs, increased their energy resiliency and assure their supply. For a modeled time-series energy requirement that varied between 2.4 MW and 5.1 MW, the optimal wind system size was 9.9 MW of installed wind power paired with a 741 kWh battery. Assuming an …


Variable Speed Limit Control At Sag Curves Through Connected Vehicles: Implications Of Alternative Communications And Sensing Technologies, Reza Vatani Nezafat Apr 2019

Variable Speed Limit Control At Sag Curves Through Connected Vehicles: Implications Of Alternative Communications And Sensing Technologies, Reza Vatani Nezafat

Civil & Environmental Engineering Theses & Dissertations

Connected vehicles (CVs) will enable new applications to improve traffic flow. This study’s focus is to investigate how potential implementation of variable speed limit (VSL) through different types of communication and sensing technologies on CVs may improve traffic flow at a sag curve. At sag curves, the gradient changes from negative to positive values which causes a reduction in the roadway capacity and congestion. A VSL algorithm is developed and implemented in a simulation environment for controlling the inflow of vehicles to a sag curve on a freeway to minimize delays and increase throughput. Both vehicle-to-vehicle (V2V) and infrastructure-to-vehicle (I2V) …


Assessment And Correction Of Lidar-Derived Dems In The Coastal Marshes Of Louisiana, William M. Lauve Mar 2019

Assessment And Correction Of Lidar-Derived Dems In The Coastal Marshes Of Louisiana, William M. Lauve

LSU Master's Theses

The onset of airborne light detection and ranging (lidar) has resulted in expansive, precise digital elevation models (DEMs). DEMs are essential for modeling complex systems, such as the coastal land margin of Louisiana. They are used for many applications (e.g. tide, storm surge, and ecological modeling) and by diverse groups (e.g. state and federal agencies, NGOs, and academia). However, in a marsh environment, it is difficult for airborne lidar to produce accurate bare-earth measurements and even accurate elevations are rarely verified by ground truth data. The accuracy of lidar in marshes is limited by the sensor’s resolution …


Ascending The Data Usability Gap In Mountainous Regions Through Scientist-Stakeholder Co-Production, Alan Rhoades Mar 2019

Ascending The Data Usability Gap In Mountainous Regions Through Scientist-Stakeholder Co-Production, Alan Rhoades

Spring Runoff Conference

No abstract provided.


Water Challenges In The Lower Colorado River Basin And The Drought Contingency Plan, Sharon Megdal Mar 2019

Water Challenges In The Lower Colorado River Basin And The Drought Contingency Plan, Sharon Megdal

Spring Runoff Conference

No abstract provided.


Water Management In The West—A Federal Perspective, Brent Esplin Mar 2019

Water Management In The West—A Federal Perspective, Brent Esplin

Spring Runoff Conference

No abstract provided.


Harmful Algae Blooms In Utah, Scott Daly Mar 2019

Harmful Algae Blooms In Utah, Scott Daly

Spring Runoff Conference

No abstract provided.


An Update On Water Legislation From The 2019 Utah Legislative Session, Tim Hawkes Mar 2019

An Update On Water Legislation From The 2019 Utah Legislative Session, Tim Hawkes

Spring Runoff Conference

No abstract provided.


Spring Runoff Conference 2019: Water Challenges In The West, Spring Runoff Conference Mar 2019

Spring Runoff Conference 2019: Water Challenges In The West, Spring Runoff Conference

Spring Runoff Conference

The Spring Runoff Conference, hosted by the USU Water Initiative, is held annually on the campus of Utah State University. The conference provides a forum for interdisciplinary sharing and exchange of ideas on water-related issues in Utah and the lntermountain Region


Seismic Landslide Hazard Mapping For Greater Vancouver, British Columbia, Ali Fallah Yeznabad, Sheri E. Molnar, Hesham M. El Naggar Mar 2019

Seismic Landslide Hazard Mapping For Greater Vancouver, British Columbia, Ali Fallah Yeznabad, Sheri E. Molnar, Hesham M. El Naggar

Western Research Forum

The lower Mainland of southwest British Columbia (BC) hosts about 3.5 million people and significant infrastructures of national importance. Southwestern BC has the highest seismic risk in Canada with significant potential to cause earthquake-induced hazards including tsunamis, liquefaction and landslides. A Cascadia mega-thrust (MW 9) earthquake is predicted to generate $75 billion Canadian dollars in losses. This damage can be resulted from ground shaking or its secondary phenomena like landslides; ground shaking during earthquakes may trigger landslides that can damage or destroy buildings, bury roads and highways and kill and injure people. In Canada, during the past century and …


Bridge Deck Delamination Segmentation Based On Aerial Thermography Through Regularized Grayscale Morphological Reconstruction And Gradient Statistics, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen Mar 2019

Bridge Deck Delamination Segmentation Based On Aerial Thermography Through Regularized Grayscale Morphological Reconstruction And Gradient Statistics, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Environmental and surface texture-induced temperature variation across the bridge deck is a major source of errors in delamination detection through thermography. This type of external noise poises a significant challenge for conventional quantitative methods such as global thresholding and k-means clustering. An iterative top-down approach is proposed for delamination segmentation based on grayscale morphological reconstruction. A weight-decay function was used to regularize the reconstruction for regional maxima extraction. The mean and coefficient of variation of temperature gradient estimated from delamination boundaries were used for discrimination. The proposed approach was tested on a lab experiment and an in-service bridge deck. The …


The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman Mar 2019

The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The sunlight photochemistry of the organic chromophore pyruvic acid (PA) in water generates ketyl and acetyl radicals that contribute to the production and processing of atmospheric aerosols. The photochemical mechanism is highly sensitive to dissolved oxygen content, [O2(aq)], among other environmental conditions. Thus, herein we investigate the photolysis (λ ≥ 305 nm) of 10–200 mM PA at pH 1.0 in water covering the relevant range 0 ≤ [O2(aq)] ≤ 1.3 mM. The rapid consumption of dissolved oxygen by the intermediate photolytic radicals is monitored in real time with a dissolved oxygen electrode. …


Modeled Affinity Constants For Phosphorus Adsorption And Desorption Due To Saltwater Intrusion, Yasemin Taşcı Mar 2019

Modeled Affinity Constants For Phosphorus Adsorption And Desorption Due To Saltwater Intrusion, Yasemin Taşcı

USF Tampa Graduate Theses and Dissertations

It is important to understand the processes that regulate phosphorus (P) fluxes to coastal environments, because P is an important nutrient in coastal ecosystems. Phosphorus adsorbs to the surface of minerals in sediment and bedrock, and an influx of seawater can cause some of that P to desorb, raising the P concentration of ambient water. Although seawater-induced P desorption is thought to be an important source of P to coastal environments, the chemical reactions that underlie it have not been established. Previous work provides some relevant surface reactions and associated affinity constants between various aqueous P species and the surface …


Iron Mediated Organic Preservation In A River Influenced Continental Margin, Neha Ajit Ghaisas Mar 2019

Iron Mediated Organic Preservation In A River Influenced Continental Margin, Neha Ajit Ghaisas

LSU Doctoral Dissertations

Continental margins such as the Mississippi river influenced Louisiana shelf (MIS), are important land-ocean interfaces where excessive water column productivity and rapid burial results in large amounts of organic carbon (OC) being sequestered in the sediments. The preservation of OC in sediments is controlled by a number of processes among which mineral-OC interactions are considered to be more important. Specifically, the interactions between sediment iron (Fe) species and OC have been shown to promote carbon preservation. However, the exact nature of preservation mechanism is not well understood and is based on limited global data, which specifically lacks estimates from large …


Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle Mar 2019

Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle

Civil and Environmental Engineering Faculty Publications and Presentations

Ecosystem water-use efficiency (WUE) is defined as the ratio of carbon gain (i.e., gross primary productivity; GPP) to water consumption (i.e., evapotranspiration; ET). WUE is markedly influential on carbon and water cycles, both of which are fundamental for ecosystem state, climate and the environment. Drought can affect WUE, subsequently disturbing the composition and functionality of terrestrial ecosystems. In this study, the impacts of drought on WUE and its components (i.e., GPP and ET) are assessed across the Contiguous US (CONUS) at fine spatial and temporal resolutions. Soil moisture simulations from land surface modeling are utilized to detect and characterize agricultural …


Thermographic Laplacian-Pyramid Filtering To Enhance Delamination Detection In Concrete Structure, Chongsheng Cheng, Ri Na, Zhigang Shen Mar 2019

Thermographic Laplacian-Pyramid Filtering To Enhance Delamination Detection In Concrete Structure, Chongsheng Cheng, Ri Na, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Despite decades of efforts using thermography to detect delamination in concrete decks, challenges still exist in removing environmental noise from thermal images. The performance of conventional temperature-contrast approaches can be significantly limited by environment-induced non-uniform temperature distribution across imaging spaces. Time-series based methodologies were found robust to spatial temperature non-uniformity but requires extended period to collect data. A new empirical image filtering method is introduced in this paper to enhance the delamination detection using blob detection method that originated from computer vison. The proposed method employs a Laplacian of Gaussian filter to achieve multi-scale detection of abnormal thermal patterns by …


Changes In Snow Phenology From 1979 To 2016 Over The Tianshan Mountains, Central Asia, Tao Yang, Qian Li, Sajjad Ahmad, Hongfei Zhou, Lanhai Li Mar 2019

Changes In Snow Phenology From 1979 To 2016 Over The Tianshan Mountains, Central Asia, Tao Yang, Qian Li, Sajjad Ahmad, Hongfei Zhou, Lanhai Li

Civil and Environmental Engineering and Construction Faculty Research

Snowmelt from the Tianshan Mountains (TS) is a major contributor to the water resources of the Central Asian region. Thus, changes in snow phenology over the TS have significant implications for regional water supplies and ecosystem services. However, the characteristics of changes in snow phenology and their influences on the climate are poorly understood throughout the entire TS due to the lack of in situ observations, limitations of optical remote sensing due to clouds, and decentralized political landscapes. Using passive microwave remote sensing snow data from 1979 to 2016 across the TS, this study investigates the spatiotemporal variations of snow …


Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth Feb 2019

Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth

Plant and Soil Sciences Faculty Publications

Stony soils are distributed all over the world. The study of their characteristics has gained importance lately due to their increasing use as agricultural soils. The effect that rock fragments exert on the soil hydraulic properties is difficult to measure in situ, and is usually derived from the fine earth properties. However, the corrections used so far do not seem accurate for all types of stony soils. Our objective was to assess the adequacy of estimating the hydraulic properties of a stony soil from the fine earth ones by correcting the latter by the volume occupied by rock fragments. To …


Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen Feb 2019

Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen

Daugherty Water for Food Global Institute: Faculty Publications

Green water––rainfall over land that eventually flows back to the atmosphere as evapotranspiration––is the main source of water to produce food, feed, fiber, timber, and bioenergy. To understand how freshwater scarcity constrains production of these goods, we need to consider limits to the green water footprint (WFg), the green water flow allocated to human society. However, research traditionally focuses on scarcity of blue water––groundwater and surface water. Here we expand the debate on water scarcity by considering green water scarcity (WSg). At 5 × 5 arc-minute spatial resolution, we quantify WFg and the maximum sustainable level to this footprint (WFg,m), …


Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki Jan 2019

Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki

Publications and Research

In this report, we present historical time series of surface area, volume, and elevation for lakes Azuei (Haiti) and Enriquillo (Dominican Republic). The intention is to present a history of the lakes’ levels for both bodies of water as derived from Landsat imagery that is augmented by reports and narratives that reach further back in time. We also summarize lake level time series data collected and developed through various other efforts and compare these data sets to our time series. The time series contains 45 years’ worth of data ranging from 1972 to 2017 which we developed from Landsat imagery …


Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic Jan 2019

Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Understanding how irrigation is used across agricultural landscapes is essential to support efforts to grow more food while reducing pressures on limited freshwater resources. However, to date, few studies have analyzed the underlying spatial and temporal variability in farmers’ individual water use decisions at a landscape scale.Wecompare estimates of irrigation water requirements derived using state-of-the-art remote sensing models with metered abstraction records for 1400 fields over a 13 year period in the US state of Nebraska, one of the world’s most intensively irrigated agricultural regions. Weshow that farmers’ observed water use decisions often diverge significantly from biophysical estimates of crop …


Pedestrian Safety -- Fundamental To A Walkable City, Joshua Herrera, Patrick Mcdevitt, Preeti Swaminathan, Raghuram Srinivas Jan 2019

Pedestrian Safety -- Fundamental To A Walkable City, Joshua Herrera, Patrick Mcdevitt, Preeti Swaminathan, Raghuram Srinivas

SMU Data Science Review

In this paper, we present a method to identify urban areas with a higher likelihood of pedestrian safety related events. Pedestrian safety related events are pedestrian-vehicle interactions that result in fatalities, injuries, accidents without injury, or near--misses between pedestrians and vehicles. To develop a solution to this problem of identifying likely event locations, we assemble data, primarily from the City of Cincinnati and Hamilton County, that include safety reports from a five year period, geographic information for these events, citizen survey of pedestrian reported concerns, non-emergency requests for service for any cause in the city, property values and public transportation …


An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt Jan 2019

An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt

LSU Doctoral Dissertations

Mesocosms were constructed to allow scientists to isolate variables in a microtidal marsh environment, mimicking the natural conditions found in Terrebonne Bay. The control offered by these mesocosms is given by a process control system that takes user inputs and automates water movement. Twelve mesocosms were constructed, each holding 4.02 m3 (142 ft3) of marsh soil and 3.88 m3 (137 ft3) of water to give 3 experimental levels and a control, all in triplicate.

Each mesocosms that was constructed contained marsh plants in soil plugs 9 feet in diameter and 3 feet deep. These …


Experiment Study Of Lateral Unloading Stress Path And Excess Pore Water Pressure On Creep Behavior Of Soft Soil, Wei Huang, Kejun Wen, Dongsheng Li, Xiaojia Deng, Lin Li, Haifei Jiang, Farshad Amini Jan 2019

Experiment Study Of Lateral Unloading Stress Path And Excess Pore Water Pressure On Creep Behavior Of Soft Soil, Wei Huang, Kejun Wen, Dongsheng Li, Xiaojia Deng, Lin Li, Haifei Jiang, Farshad Amini

Civil and Architectural Engineering Faculty Research

The unloading creep behavior of soft soil under lateral unloading stress path and excess pore water pressure is the core problem of time-dependent analysis of surrounding rock deformation under excavation of soft soil. The soft soil in Shenzhen, China, was selected in this study. The triaxial unloading creep tests of soft soil under different initial excess pore water pressures (0, 20, 40, and 60 kPa) were conducted with the K0 consolidation and lateral unloading stress paths. The results show that the unloading creep of soft soil was divided into three stages: attenuation creep, constant velocity creep, and accelerated creep. The …


Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray Jan 2019

Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

In the race to enhance agricultural productivity, irrigation will become more dependent on poorly characterized and virtually unmonitored sources of water. Increased use of irrigation water has led to impaired water and soil quality in many areas. Historically, soil salinization and reduced crop productivity have been the primary focus of irrigation water quality. Recently, there is increasing evidence for the occurrence of geogenic contaminants in water. The appearance of trace elements and an increase in the use of wastewater has highlighted the vulnerability and complexities of the composition of irrigation water and its role in ensuring proper crop growth, and …


Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands Jan 2019

Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands

Daugherty Water for Food Global Institute: Faculty Publications

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused …


Impact Of The Application Of Domestic Wastewater By Subsurface Drip Irrigation On The Soil Solution In Sugarcane Cultivation, Aline Azevedo Nazário, Ivo Zution Gonçalves, Eduardo Augusto Agnellos Barbosa, Leonardo Nazário Silva Dos Santos, Daniel Rodrigues Cavalcante Feitosa, Edson Eiji Matsura Jan 2019

Impact Of The Application Of Domestic Wastewater By Subsurface Drip Irrigation On The Soil Solution In Sugarcane Cultivation, Aline Azevedo Nazário, Ivo Zution Gonçalves, Eduardo Augusto Agnellos Barbosa, Leonardo Nazário Silva Dos Santos, Daniel Rodrigues Cavalcante Feitosa, Edson Eiji Matsura

Daugherty Water for Food Global Institute: Faculty Publications

The agricultural use of domestic sewage is a viable alternative for recycling nutrients; however, there is concern regarding the impact of its use due to the concentration of chemical elements present in this type of effluent. The use of principal component analysis determines the existence or lack of anomalous samples and the relations between measured variables and their relative contribution among samples that help in monitoring the impact of the use of effluents on soil chemical components. Thus, the objective of this work was to identify nutrient ions present in the soil solution during the first ratoon sugarcane irrigated with …


Public Attitudes About Private Forest Management And Government Involvement In The Southeastern United States, Melissa M. Kreye, Renata Rimsaite, Damian C. Adams Jan 2019

Public Attitudes About Private Forest Management And Government Involvement In The Southeastern United States, Melissa M. Kreye, Renata Rimsaite, Damian C. Adams

Daugherty Water for Food Global Institute: Faculty Publications

In the southern United States the country’s top wood-producing region, factors such as intergenerational land transfer and population spillover from urban areas have resulted in forestland conversion and reduced production of critical ecosystem services associated with forest systems (e.g., timber, clean water supply, wildlife habitat). Public attitudes, which drive forestland policy prescriptions, may also be evolving due to the way people experience and perceive forests (e.g., recreation), and think about the role of government in private forest decisions. These changes have significant implications for forestland management and the forest-based economy, both locally and globally. We present the results of a …