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Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski Mar 2022

Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski

Theses and Dissertations

Atmospheric Water Generators (AWG) extract water from the air using one of three available technologies: refrigeration, sorption, and fog harvesting. A refrigeration device works like a dehumidifier and works best in conditions above 60% relative humidity. A sorption device utilizes a desiccant to extract the water vapor from the air and works in very low humidity levels. A fog harvesting device utilizes a mesh to capture the water vapor from the air and requires 100% relative humidity. In this research, I analyze two refrigeration-based devices and one sorption-based device and their efficacy in providing supplemental water supply. Due to climatological …

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Application Of Machine Learning Models With Numerical Simulations Of An Experimental Microwave Induced Plasma Gasification Reactor, Owen D. Sedej Mar 2022

Application Of Machine Learning Models With Numerical Simulations Of An Experimental Microwave Induced Plasma Gasification Reactor, Owen D. Sedej

Theses and Dissertations

This thesis aims to contribute to the future development of this technology by providing an in-depth literature review of how this technology physically operates and can be numerically modeled. Additionally, this thesis reviews literature of machine learning models that have been applied to gasification to make accurate predictions regarding the system. Finally, this thesis provides a framework of how to numerically model an experimental plasma gasification reactor in order to inform a variety of machine learning models.

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Natural Infrastructure Alternatives Mitigate Hurricane-Driven Flood Vulnerability: Application To Tyndall Air Force Base, Kiara L. Vance Mar 2022

Natural Infrastructure Alternatives Mitigate Hurricane-Driven Flood Vulnerability: Application To Tyndall Air Force Base, Kiara L. Vance

Theses and Dissertations

Hurricane frequency and magnitude intensification are expected over the remainder of the twenty-first century. Uncertainty in future projections requires that coastal communities approach adaptation decisions with caution. Traditional approaches are costly and inflexible. Soft policy adaptations are largely unenforceable. Hard, natural adaptations have emerged as an opportunity to partially mitigate the growing risk of extreme flooding, without the large investments required for traditional approaches, where natural infrastructure already exists. Existing literature for natural adaptations has not leveraged intensification expectations for hurricane events. This research uses multihazard damage evaluation software and spatial analysis to investigate placement of dredged sediment as a …

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Prioritizing Water Distribution Network Asset Maintenance Using Graph Theory Methods, Ashton E. Doyal Mar 2022

Prioritizing Water Distribution Network Asset Maintenance Using Graph Theory Methods, Ashton E. Doyal

Theses and Dissertations

Water distribution networks, like any other large infrastructure system, should be designed for reliability and resilience to resist failure. A literature review of graph theory methods pertaining to water distribution networks reveals a wide scope of mathematical and statistical measures that can be used to identify and classify many important features of a network. From this, an analysis using a combination of graph theory metrics and generated condition indices for the pipes is performed on the Tyndall drinking water system as a case study. The goal is to provide understanding to the risk of the current system and propose asset …

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Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson Mar 2022

Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson

Theses and Dissertations

The intensity of extreme weather events, specifically wildfires, along the West Coast has slowly grown overtime due to atmospheric changes caused by climate change. The Air Force, though aware of the threat that is wildfire, does not currently have a quantitative way to assess the hazard to base locations. In this paper, burn probability is quantitatively calculated through the geospatial analysis programs to provide a means of assessing wildfire vulnerability. The FlamMap fire simulator generated burn probabilities for Vandenberg Air Force Base using climate data generated by the remote automated weather station on the base to highlight how the burn …

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A Case Study Comparing Panelization And Modularization Construction Methods, Tuukka Juhani Jaakkola Mar 2022

A Case Study Comparing Panelization And Modularization Construction Methods, Tuukka Juhani Jaakkola

Construction Management

Construction industry is notoriously inefficient industry with a lot of room for improvement. Construction companies are constantly looking to increase their efficiency. NCC Finland decided to explore the method of modular construction as part of the efforts to increase production. NCC also happened to build a similarly sized project with the more traditional method of panelization and tilt-up construction. This Case study explores the experience of NCC as the general contractor of both projects. The aim is to understand the differences of the challenges and benefits experienced by the team from NCC. The findings show that Modular construction offers wide …

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Solving The Negative Earnings Dilemma Of Multistage Bidding In Public Construction And Infrastructure Projects: A Game Theory-Based Approach, Muaz O. Ahmed, Islam H. El-Adaway, Kalyn T. Coatney Mar 2022

Solving The Negative Earnings Dilemma Of Multistage Bidding In Public Construction And Infrastructure Projects: A Game Theory-Based Approach, Muaz O. Ahmed, Islam H. El-Adaway, Kalyn T. Coatney

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With the tremendous increase in spending on public projects, contractors need to employ efficient and effective bidding strategies to cope with the competitive bidding environment. Usually, general contractors carry a portion of the work and subcontract other parts to eventually submit a holistic joint bid. This bidding setting is referred to as multistage bidding where subcontractors submit their quotations/bids to the general contractor, after which the general contractor submits a final joint bid for the whole project. In a multistage bidding environment, general contractors may be faced with an increase in the probability of negative or below normal profits. Despite …

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A Case Study Of Community-Engaged Design: Creating Parametric Insurance To Meet The Safety Needs Of Fisherfolk In The Caribbean, Daniel B. Oerther Mar 2022

A Case Study Of Community-Engaged Design: Creating Parametric Insurance To Meet The Safety Needs Of Fisherfolk In The Caribbean, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The creation of the Caribbean Ocean and Aquaculture Sustainability faciliTy (COAST) is used as a case study of community-engaged design addressing safety needs. COAST is a parametric insurance product, sold to national governments, which was designed to meet the food and nutrition security of small- and medium-scale fisherfolk. The design of COAST is an example of convergence research, where the discipline of engineering was integrated with another discipline to solve pressing societal needs of Caribbean fisherfolk. This case study demonstrates that community-engaged design helps to (1) identify and include historically underrepresented stakeholders, (2) emphasize the importance of professional responsibility for …

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Uncertainties In The Projected Patterns Of Wave-Driven Longshore Sediment Transport Along A Non-Straight Coastline, Amin Reza Zarifsanayei, José A. A. Antolínez, Amir Etemad-Shahidi, Nick Cartwright, Darrell Strauss, Gil Lemos Feb 2022

Uncertainties In The Projected Patterns Of Wave-Driven Longshore Sediment Transport Along A Non-Straight Coastline, Amin Reza Zarifsanayei, José A. A. Antolínez, Amir Etemad-Shahidi, Nick Cartwright, Darrell Strauss, Gil Lemos

Research outputs 2022 to 2026

This study quantifies the uncertainties in the projected changes in potential longshore sediment transport (LST) rates along a non-straight coastline. Four main sources of uncertainty, including the choice of emission scenarios, Global Circulation Model-driven offshore wave datasets (GCM-Ws), LST models, and their non-linear interactions were addressed through two ensemble modelling frameworks. The first ensemble consisted of the offshore wave forcing conditions without any bias correction (i.e., wave parameters extracted from eight datasets of GCM-Ws for baseline period 1979–2005, and future period 2081–2100 under two emission scenarios), a hybrid wave transformation method, and eight LST models (i.e., four bulk formulae, four …

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Resilient Modulus Of Siliciclastic Unbound Granular Materials Under Repeated Wheel Loading, Siya Rimoyi Feb 2022

Resilient Modulus Of Siliciclastic Unbound Granular Materials Under Repeated Wheel Loading, Siya Rimoyi

Tanzania Journal of Engineering and Technology (TJET)

The Resilient Modulus (Mr) is a fundamental material property input in modern Mechanistic-Empirical (M-E) pavements structural design. Empirical pavement design methods have been in use over a long period during which large databases of four- days-soaked California Bearing Ratio (CBR) values at or near the Maximum Dry Density have been generated in the strength assessments for Unbound Granular Materials (UGMs). In the adoption of the M-E design approach researchers have so far attempted with various degrees of success to develop models to derive resilient modulus from the conventional CBR-based databases. This study provides an extensive laboratory experimental study to investigate …

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Chlorine Taste Threshold And Acceptability As A Water Disinfectant Among Indigenous Ngäbe And Non-Indigenous In Rural Panama, Ashley Osler Feb 2022

Chlorine Taste Threshold And Acceptability As A Water Disinfectant Among Indigenous Ngäbe And Non-Indigenous In Rural Panama, Ashley Osler

USF Tampa Graduate Theses and Dissertations

More than two billion people globally still lack access to safely managed drinking water (WHO & UNICEF, 2021). Although gains in access to water service over the past two decades have been large, universal access to safe and affordable drinking water (SDG 6, target 6.1) is not on track to be achieved. In Panama, safely managed drinking water access has not been measured. However, the data on basic water access illustrates the large disparities between rural and urban areas of Panama. While 98% of urban Panamanian households have basic access to water, only 86% of rural Panamanian households, and 54% …

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Efficacy Of Softener For Enhancing Fatigue And Low-Temperature Performance Of Asphalt Binders With High Rap, Sumon Roy Feb 2022

Efficacy Of Softener For Enhancing Fatigue And Low-Temperature Performance Of Asphalt Binders With High Rap, Sumon Roy

Student Theses and Dissertations

The use of a higher percentage of reclaimed asphalt pavement (RAP) in asphalt concrete can lead to developing premature failure of asphalt pavements due to fatigue and/or low-temperature cracking. The incorporation of softening agents in asphalt binders can resolve these problems and enhance pavement durability. This study aims to evaluate the effectiveness of waste-based softening agents for enhancing the properties of asphalt mixes with high RAP contents. Waste cooking oil (WCO), and engine bottom oil (EBO) along with a commercial rejuvenator were investigated in this study. Three types of Performance Grade (PG) binders, each collected from two different sources, used …

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Predicting Seismic Site Coefficients For Northeast Arkansas (Nea) By Performing Site Specific Ground Motion Response Analysis (Ssgmra), Md Radiue Islam Feb 2022

Predicting Seismic Site Coefficients For Northeast Arkansas (Nea) By Performing Site Specific Ground Motion Response Analysis (Ssgmra), Md Radiue Islam

Student Theses and Dissertations

Northeast Arkansas (NEA) has a deep deposition of soil overlying the bedrock. The code-based design approach e.g., the American Association of State Highway and Transportation Officials (AASHTO) does not account for deep deposition of soil overlying the bedrock. As a result, structures with short-period spectral accelerations are overdesigned at significant cost, and structures with long-period spectral accelerations are under-designed at significant risk. The purpose of this study is to perform SSGMRA for areas in NEA and predict seismic site factors. Seismic hazard analyses have been carried out, and one dimensional (1D) site response analysis has been performed for seven different …

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Utah's Food Processing Industry Can Manufacture Products From Cbd-Containing Lipids That Have Superior Texture And Consistency, Joseph Cooney, Isaac Hilton Feb 2022

Utah's Food Processing Industry Can Manufacture Products From Cbd-Containing Lipids That Have Superior Texture And Consistency, Joseph Cooney, Isaac Hilton

Research on Capitol Hill

Sophomore Joseph is an Honors student and Undergraduate Research Fellow studying physics. Freshman Isaac, of Kaysville, studies civil and environmental engineering. Joseph and Isaac are exploring how cannabinoids impact the way that lipids function. A common way CBD is packaged is within foods, where it is frequently added to fats like cocoa butter or palm oil, and as the market for such products increase producers need to understand CBD will change the behavior of the fats they are using.In addition to this work, Joseph also volunteers for a physics lab. “Undergraduate research has let me explore fields outside my major …

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Global And Regional Sea Level Rise Scenarios For The United States, National Oceanic And Atmospheric Administration (Noaa) Feb 2022

Global And Regional Sea Level Rise Scenarios For The United States, National Oceanic And Atmospheric Administration (Noaa)

State & Federal Reports and Publications

This report and accompanying datasets from the U.S. Sea Level Rise and Coastal Flood Hazard Scenarios and Tools Interagency Task Force provide 1) sea level rise scenarios to 2150 by decade that include estimates of vertical land motion and 2) a set of extreme water level probabilities for various heights along the U.S. coastline. These data are available at 1-degree grids along the U.S. coastline and downscaled specifically at NOAA tide-gauge locations. Estimates of flood exposure are assessed using contemporary U.S. coastal flood-severity thresholds for current conditions (e.g., sea levels and infrastructure footprint) and for the next 30 years (out …

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Using Phreeqc To Model Cement Hydration, Niall Holmes Dr., Mark Tyrer, Roger P. West Prof, Aaron Lowe, Denis Kelliher Feb 2022

Using Phreeqc To Model Cement Hydration, Niall Holmes Dr., Mark Tyrer, Roger P. West Prof, Aaron Lowe, Denis Kelliher

Articles

This paper presents the steps involved in undertaking an analysis of hydrating cements with different levels of limestone powder using the PHREEQC geochemical software with the Notepad++ editor. The analysis begins with determining which solid phases are thermodynamically predicted to precipitate and form using the oxide compositions of commercial CEM I and CEM II/A-L cements. When the phases are known, PHREEQC is programmed to provide predictions of the phase dissolution and phase assemblage over time (here, 1000 days of hydration) as well as the pore solution chemistry. Thermodynamics has been successfully applied to the field of cement hydration to predict …

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Evaluation Of Gev Over Lp3 When Predicting Return Period Annual Exceedance For Santa Ana, San Gabriel And Urbanized Regions In California, Maria Beatriz De Paula Macedo Feb 2022

Evaluation Of Gev Over Lp3 When Predicting Return Period Annual Exceedance For Santa Ana, San Gabriel And Urbanized Regions In California, Maria Beatriz De Paula Macedo

LMU Theses and Dissertations

The objective of this present thesis was to determine whether GEV (Generalized Extreme Value) itself can be a more conservative distribution than LP3 (Log Pearson III) associated with other methods, such as the B17B weighting procedure with Single Grubbs-Beck (SGB) for low outliers, when determining the projected floods in a flood frequency analysis (FFA) for Santa Ana and San Gabriel regions and other urbanized stream gages present in California. In this work, USGS PeakFQ was utilized. From the results obtained, it was possible to state that GEV fitting results were directly affected by the length of the data. When the …

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Characteristics And Assessing Biological Risks Of Airborne Bacteria In Waste Sorting Plant, Abbas Norouzian Baghani, Somayeh Golbaz, Gholamreza Ebrahimzadeh, Marcelo I. Guzman, Mahdieh Delikhoon, Mehdi Jamshidi Rastani, Abdullah Barkhordari, Ramin Nabizadeh Feb 2022

Characteristics And Assessing Biological Risks Of Airborne Bacteria In Waste Sorting Plant, Abbas Norouzian Baghani, Somayeh Golbaz, Gholamreza Ebrahimzadeh, Marcelo I. Guzman, Mahdieh Delikhoon, Mehdi Jamshidi Rastani, Abdullah Barkhordari, Ramin Nabizadeh

Chemistry Faculty Publications

Examining the concentration and types of airborne bacteria in waste paper and cardboard sorting plants (WPCSP) is an urgent matter to inform policy makers about the health impacts on exposed workers. Herein, we collected 20 samples at 9 points of a WPCSP every 6 winter days, and found that the most abundant airborne bacteria were positively and negatively correlated to relative humidity and temperature, respectively. The most abundant airborne bacteria (in units of CFU m−3) were: Staphylococcus sp. (72.4) > Micrococcus sp. (52.2) > Bacillus sp. (30.3) > Enterococcus sp. (24.0) > Serratia marcescens (20.1) > E. coli (19.1) > Pseudomonas sp. (16.0) > Nocardia …

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Development Of Guidelines For Collecting Transit Ridership Data, Hong Yang, Kun Xie, Sherif Ishak, Qingyu Ma, Yang Liu Feb 2022

Development Of Guidelines For Collecting Transit Ridership Data, Hong Yang, Kun Xie, Sherif Ishak, Qingyu Ma, Yang Liu

Computational Modeling & Simulation Engineering Faculty Publications

Transit ridership is a critical determinant for many transit applications such as operation optimizations and project prioritization under performance-based funding mechanisms. As a result, the quality of ridership data is of utmost importance to both transit administrative agencies and transit operators. Many transit operators in Virginia report their ridership data to the Department of Rail and Public Transportation (DRPT) and the National Transit Database (NTD). However, with no specific guidelines available to transit agencies in Virginia for collecting ridership data, the heterogeneous mixture of diverse data collection methods and technologies has often raised concerns about the consistency and quality of …

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Application Of Nonlinear Time Series And Machine Learning Algorithms For Forecasting Groundwater Flooding In A Lowland Karst Area, Bidroha Basu, Patrick Morrissey, Laurence Gill Feb 2022

Application Of Nonlinear Time Series And Machine Learning Algorithms For Forecasting Groundwater Flooding In A Lowland Karst Area, Bidroha Basu, Patrick Morrissey, Laurence Gill

Publications

In karst limestone areas interactions between ground and surface waters can be frequent, particularly in low lying areas, linked to the unique hydrogeological dynamics of that bedrock aquifer. In extreme hydrological conditions, however, this can lead to wide-spread, long-duration flooding, resulting in significant cost and disruption. This study develops and compares a nonlinear time-series analysis based nonlinear autoregressive model with exogenous variables (NARX), machine learning based near support vector regression as well as a linear time-series ARX model in terms of their performance to predict groundwater flooding in a lowland karst area of Ireland. The models have been developed upon …

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Management Of Change Orders In Infrastructure Transportation Projects, Rayan H. Assaad, Muaz O. Ahmed, Islam H. El-Adaway, Pramen P. Shrestha Feb 2022

Management Of Change Orders In Infrastructure Transportation Projects, Rayan H. Assaad, Muaz O. Ahmed, Islam H. El-Adaway, Pramen P. Shrestha

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Illinois Department of Transportation (IDOT) will handle many upcoming projects due to the recent statewide infrastructure strategic plan and the fast-track efforts affecting many infrastructure projects amid COVID-19. Nevertheless, many change orders are anticipated to occur on IDOT's projects. Thus, this paper examines the proper contractual management of changes within IDOT infrastructure transportation projects by following a research method based on the integration between a desktop analysis and a focus group analysis. The desktop analysis involved collecting information and data from existing resources, case studies, and documents related to change orders. The focus group analysis involved consulting with change …

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Mathematical Modeling And Optimization Of Water Efficiency In Residential Buildings, Mahmoud Amin Jan 2022

Mathematical Modeling And Optimization Of Water Efficiency In Residential Buildings, Mahmoud Amin

Theses and Dissertations

Water scarcity is a global issue that is rapidly worsening. The domestic sector is one of the fastest-growing segments of world water usage. Many researchers have explored various approaches to promote sustainable uses of water, with Greywater (GW) recycling and utilization of innovative plumbing fixtures among the methods presented to reduce freshwater consumption for domestic usage. Nonetheless, previous studies have dealt with both means independently, with limited analysis of the integrated effect of utilizing GW recycling with innovative plumbing fixtures, both on quality of supplied water, as well as on cost of the integrated system. Accordingly, this research aims at …

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Final Bid Price Estimation For Negotiated Contracts: Bargaining Game Theory Approach, Amr El Mahallaoui Jan 2022

Final Bid Price Estimation For Negotiated Contracts: Bargaining Game Theory Approach, Amr El Mahallaoui

Theses and Dissertations

The wide use of the low bid method by employers for awarding construction contracts has created an aggressively competitive environment among contractors in the construction industry. As a result, a contractor may resort to use a low mark-up percentage for his bid to increase his chances of winning, which may lead to losses and conflicts in case he is awarded the project. Additionally, a contractor who reaches the final negotiations stage for a certain project is faced by the dilemma of the minimum discount percentage he may need to offer to the employer that maximizes his chance to win the …

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Long Short-Term Memory Based Subsurface Drainage Control For Rainfall-Induced Landslide Prevention, Aynaz Biniyaz, Behnam Azmoon, Ye Sun, Zhen Liu Jan 2022

Long Short-Term Memory Based Subsurface Drainage Control For Rainfall-Induced Landslide Prevention, Aynaz Biniyaz, Behnam Azmoon, Ye Sun, Zhen Liu

Michigan Tech Publications, Part 1

Subsurface drainage has been widely accepted to mitigate the hazard of landslides in areas prone to flooding. Specifically, the use of drainage wells with pumping systems has been recognized as an effective short-term solution to lower the groundwater table. However, this method has not been well considered for long-term purposes due to potentially high labor costs. This study aims to investigate the idea of an autonomous pumping system for subsurface drainage by leveraging con-ventional geotechnical engineering solutions and a deep learning technique—Long-Short Term Memory (LSTM)—to establish a geotechnical cyber-physical system for rainfall-induced landslide prevention. For this purpose, a typical soil …

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A Comprehensive Evaluation Of Wastewater Grit Characteristics And Its Application In The Design Of A Facility-Specific Grit Removal Solution, Tetiana Kolsovska Jan 2022

A Comprehensive Evaluation Of Wastewater Grit Characteristics And Its Application In The Design Of A Facility-Specific Grit Removal Solution, Tetiana Kolsovska

Theses and Dissertations

Tailored solutions for wastewater treatment plants (WWTPs) are becoming more prevalent for optimization of treatment process, based on the unique quality of the influent received by each facility. In-depth evaluation of the influent properties is necessary for design of the most appropriate treatment system. In this study, wastewater grit was evaluated in terms of its quantity, particle size distribution, total organic carbon (TOC) content, including fats, oils, and grease (FOG), and settling velocity of the particles, over the course of one year at the headworks, collection network, and through the treatment stages of the Atlantic County Utilities Authority (ACUA) WWTP, …

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Kinetic Study Of The Anaerobic Digestion Of Recycled Paper Mill Effluent (Rpme) By Using A Novel Modified Anaerobic Hybrid Baffled (Mahb) Reactor, Siti Roshayu Hassan, Yung-Tse Hung, Irvan Dahlan, Hamidi Abdul Aziz Jan 2022

Kinetic Study Of The Anaerobic Digestion Of Recycled Paper Mill Effluent (Rpme) By Using A Novel Modified Anaerobic Hybrid Baffled (Mahb) Reactor, Siti Roshayu Hassan, Yung-Tse Hung, Irvan Dahlan, Hamidi Abdul Aziz

Civil and Environmental Engineering Faculty Publications

The process kinetics of an anaerobic digestion process for treating recycled paper mill effluent (RPME) was investigated. A laboratory-scale modified anaerobic hybrid baffled reactor (MAHB) was operated at hydraulic retention times of 1, 3, 5, and 7 days, and the results were analyzed for the kinetic models. A kinetic study was conducted by examining the phase kinetics of the anaerobic digestion process, which were divided into three main stages: hydrolysis kinetics, acetogenesis kinetics, and methane production kinetics. The study demonstrated that hydrolysis was the rate-limiting step. The applied Monod and Contois kinetic models showed satisfactory prediction with µmax values of …

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Modeling Vapor Transfer In Soil Water And Heat Simulations: A Modularized, Partially-Coupled Approach, Zhuangji Wang, Dennis Timlin, David Fleisher, Wenguang Sun, Sahila Beegum, Sanai Li, Ya Chen, Vandimalla R. Reddy, Katherine Tully, Robert Horton Jan 2022

Modeling Vapor Transfer In Soil Water And Heat Simulations: A Modularized, Partially-Coupled Approach, Zhuangji Wang, Dennis Timlin, David Fleisher, Wenguang Sun, Sahila Beegum, Sanai Li, Ya Chen, Vandimalla R. Reddy, Katherine Tully, Robert Horton

Nebraska Water Center: Faculty Publications

Coupled water and heat transfer models are widely used to analyze soil water content and temperature dynamics, evaluate agricultural management systems, and support crop growth modelling. In relatively dry soils, vapor transfer, rather than liquid water flux, becomes the main pathway for water redistribution. However, in some modularized soil simulators, e.g., 2DSOIL (Timlin et al., 1996), vapor transfer is not included, which may induce errors in soil water and heat modelling. Directly embedding vapor transfer into existing water and heat transfer modules may violate the modularized architecture of those simulators. Therefore, the objectives of this study are to design a …

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A Greenhouse Gas Emissions Inventory For Nebraska: Livestock And Coal Loom Large, Eric R. Holley, Adam Liska Jan 2022

A Greenhouse Gas Emissions Inventory For Nebraska: Livestock And Coal Loom Large, Eric R. Holley, Adam Liska

Adam Liska Papers

Mitigation of climate change requires the systematic identification and cataloging of emissions sources at city, state, and national levels. In this study, an inventory of annual greenhouse gas emissions from the state of Nebraska was created based on industry data, and emissions inventories were completed each year from 1990 to 2016. Nebraska’s net emissions were found to increase from 56.2 million metric tons of carbon dioxide equivalents (MMtCO2e) in 1990 to 87.4 MMtCO2e in 2016. Agriculture was found to be the sector with the most emissions (36 MMtCO2e) followed by electricity generation (21 MMtCO …

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Ferrihydrite Enrichment In The Rhizosphere Of Unsaturated Soil Improves Nutrient Retention While Limiting Arsenic And Uranium Plant Uptake, Arindam Malakar, Daniel D. Snow, Michael Kaiser, Jordan Shields, Bijesh Maharjan, Harkamal Walia, Daran Rudnick, Chittaranjan Ray Jan 2022

Ferrihydrite Enrichment In The Rhizosphere Of Unsaturated Soil Improves Nutrient Retention While Limiting Arsenic And Uranium Plant Uptake, Arindam Malakar, Daniel D. Snow, Michael Kaiser, Jordan Shields, Bijesh Maharjan, Harkamal Walia, Daran Rudnick, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

Improvement of nutrient use efficiency and limiting trace elements such as arsenic and uranium bioavailability is critical for sustainable agriculture and food safety. Arsenic and uranium possess different properties and mobility in soils, which complicates the effort to reduce their uptake by plants. Here, we postulate that unsaturated soil amended with ferrihydrite nanominerals leads to improved nutrient retention and helps reduce uptake of these geogenic contaminants. Unsaturated soil is primarily oxic and can provide a stable environment for ferrihydrite nanominerals. To demonstrate the utility of ferrihydrite soil amendment, maize was grown in an unsaturated agricultural soil that is known to …

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Supervised Machine Learning Techniques Applied To Low-Cost Air Quality Sensor Suites, Peter Wahman Jan 2022

Supervised Machine Learning Techniques Applied To Low-Cost Air Quality Sensor Suites, Peter Wahman

All Undergraduate Theses and Capstone Projects

Low-cost PM sensors have garnered interest for their ability to reduce the cost of investigating PM concentrations in both indoor and outdoor spaces. They perform well in high concentration lab testing with correlation coefficients greater than 0.9. In real-world applications, the correlation coefficients drop significantly because of sensing floors and adverse ambient conditions. There are plenty of supervised machine learning techniques that aim to correct the measurements ranging from linear regression to more advanced neural networks and random forests. This work aims to use those more complicated techniques to adjust the measurements using other data sets gathered by a sensor …

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