Civil and Environmental Engineering Commons^™

Behavioral Insights Impacting Preweaning Mortality, Md Towfiqur Rahman, G. A. Rohrer, S. R. Sharma, Y. Shi, S. M. Leonard, Tami M. Brown-Bandl

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Conclusions

This study investigated the average time spent on posture behaviors (lying, kneeling, sitting, standing) of sows by analyzing the effects of time segments, farrowing crate types, parity, heat lamp configurations, and mortality groups. Sow posture behaviors were significantly influenced by mortality, parity, crate type, heat lamps, and day category. High mortality sows spent less time lying and more time standing events. Parity 1, 2, 3 sows were more active, spending more time kneeling in transitions, lying, and sitting events. Sows in TSL crate had longer lateral right lying and standing events, while ESCSL crates sows had longer sitting events. …

Firelog: An Open-Source, Low-Cost System For Temperature Logging During Wildland Fires With High Spatial And Temporal Resolution, Nipuna Chamara, Yufeng Ge, Sabrina E. Russo

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Measuring flame, air, and soil temperatures during wildland fires, including wildfires and controlled burns in land management contexts, is crucial for research and applications in fire ecology, safety, and management in a wide array of ecosystems, from grasslands to forests. However, open-source and commercial systems are needed for measuring and logging flame and air temperatures that are user-friendly, economical, modular, and customizable. This paper details the design, development, and validation of the FireLog system. Laboratory validation experiments demonstrated high measurement accuracy, with a minimum coefficient of determination (R2) of 0.98 and the highest observed root mean square error (RMSE) of …

Cover Crops Can Reduce Greenhouse Gas Emissions From No-Till Maize In Southern Brazil: Insights From A Long-Term Field Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimélio Bayer

Adam Liska Papers

Brazil is one of the countries that has the most agricultural area under no-till (NT) management. This research study aims to evaluate life-cycle greenhouse gas (GHG) emissions from maize (M) grain production in agroecosystems that used different cover crops under NT management in southern Brazil. The data for this study were from a long-term 41-year field experiment in southern Brazil. The long-term experiment evaluated the effects of fallow (F) and cover crops (oat (O), vetch (V), cowpea (B), pigeon pea (P), and lablab (L)) on nitrous oxide and methane emissions and soil carbon (C) sequestration in maize agroecosystems. Five cropping …

Scalable Machine Learning Framework For Adaptive Irrigation Management Of Maize And Soybean In The U.S. Midwest, Precious N. Amori, Derek M. Heeren, Yeyin Shi, Eric Wilkening, Ivo Z. Goncalves, Guillermo R. Balboa, Daran R. Rudnick, Abia Katimbo, Randall S. Ritzema

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Conventional soil water balance (SWB) irrigation scheduling tools, such as FAO-56-based Spreadsheets and the Spatial Evapotranspiration Modeling Interface (SETMI), rely heavily on manual inputs and periodic field measurements, leading to delayed recommendations and missed opportunities to prevent crop stress. More critically, these tools lack the computational scalability and adaptability to leverage the high-frequency, high-volume datasets now available through modern sensing technologies. As precision irrigation increasingly depends on integrating spatially and temporally nuanced field information, there is a pressing need for decision-support systems that can process Big Data efficiently and respond in real-time. To overcome these limitations, we developed and validated …

Analyzing Reciprocating Piston Expander Performance In Small-Scale Caes Considering Expansion Mismatch And Residual Mass Losses, Mehrdad Poursadegh

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Energy storage (ES) has become an essential element of modern energy systems, particularly with the rapid growth of renewable energy sources. While these sources are central to global decarbonization efforts, their intermittent nature creates significant challenges for both grid operators and end users. To address these challenges, a wide range of storage technologies have been developed ranging from large utility-scale to small behind-the-meter units. Among these, Compressed Air Energy Storage (CAES) stands out for its long lifespan, low storage cost per unit of energy, and ability to provide both electricity and thermal energy. However, small- and micro-scale CAES systems, unlike …

A Statewide Geographic Information System (Gis) As A Predictive Tool For Locating Deeply Buried Archeological Deposits In Nebraska: Phase Iii-The Sandhills Region, Anthony L. Layzell, Rolfe D. Mandel, John Swigart, David T. Williams

Nebraska Department of Transportation: Research Reports

This project developed a GIS to assist with the identification of deeply buried cultural deposits in alluvial settings across the Sandhills region of Nebraska. Soil survey data, previous geoarchaeological investigations, landform position, and other information was used to rank the potential of any stream valley setting as low, low-moderate, moderate-high, or high potential to contain buried cultural deposits. While the presence of buried soils does not necessarily translate to presence of buried archeological sites, the potential for such sites is far greater in buried soils. The GIS can be used by NDOT and other agencies with statutory historic preservation obligations, …

Enhancing Civil Infrastructure Performance Through Lidar-Based Dynamic Monitoring And Phased-Construction Bridges, Khalid Hossam Alkady

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation aims to enhance the performance and structural integrity of civil infrastructure systems through two primary goals. The first goal is to develop and rigorously validate end-to-end frameworks for full-field monitoring of the dynamic response of civil structures via Ground-based Lidar (GBL) scanners. GBL can be employed to sample point clouds at a high sampling rate for dynamic data collection, which addresses the limitations of using contact-based sensors in structural health monitoring (SHM) applications used for early-detection of structural damage.

The second goal of this dissertation concerns the challenges associated with constructing bridges in phases, so they can remain …

Minimizing Take Of Threatened Rattlesnakes And Optimizing Project Review In Se Nebraska, Shaun Dunn, Dan Fogell, Colleen Rothe-Groleau

Nebraska Department of Transportation: Research Reports

The western massasauga (Sistrurus tergeminus) and the timber rattlesnake (Crotalus horridus) are protected under Nebraska Statute 37-801-811 and listed as threatened species. These species occur in the right-of-way (ROW) along several roads in Jefferson, Gage, Pawnee, and Richardson Counties which necessitates the need for added Environmental Review (ER) from Nebraska Department of Transportation (NDOT) staff and onsite surveys prior and during maintenance and construction to roadways. This project sought to minimize ER time, staff time, and increase the knowledge of these species in southeast Nebraska by:

1. Identifying precise locations of western massasauga brumation sites;
2. Mapping travel …

Deep Learning Vision-Based Bridge Inspection With Resource-Constrained Unmanned Aircraft Systems, Ji Young Lee

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Bridge inspection is critical for ensuring structural integrity, extending the service life of infrastructure, and minimizing maintenance costs. As bridges age and endure increasing loads, regular inspections help detect early signs of wear, such as cracks or corrosion, that could impact safety and performance. However, traditional inspection methods are labor-intensive, requiring significant time, specialized equipment, and manual access to challenging areas, which can lead to costly disruptions. Additionally, reliance on human inspectors introduces subjectivity, with assessments varying by individual expertise. These factors highlight the inefficiencies and safety risks in current inspection practices, underscoring the need for more objective, efficient solutions. …

Impacts Of Stream Bed Adjustment On Local Bridge Morphology At Highway 281, Molly G. Likins

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Nebraska sand-bed rivers have long been a part of sediment transport studies and have been used in the development of numerous well-known empirical bedload equations. Some of these studies have shown how adjustments in streambed elevation led to changes in local stream morphology. The sand-bed rivers of Nebraska are highly susceptible to such changes due to their wide, shallow cross-sections and erodibility. The objective of our study is to synthesize a hydrodynamic model with high-resolution field data and improved methods of representing sediment transport to better predict both short and long-term channel adjustments for an aggraded sand-bed river.

The field …

Numerical Study On The Behavior Of Natural And Recycled Aggregate Concretes, Shahriar Mardpour

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This thesis investigates the mechanical behavior of natural and recycled aggregate concretes (NAC and RAC) using a multi-phase numerical approach to predict performance. Growing interest in sustainable materials has led to using recycled concrete aggregates (RCA) to replace natural aggregates, creating Recycled Aggregate Concrete (RAC). Due to their different structural components, RAC and NAC exhibit varying mechanical properties, particularly in strength and durability.

This study validated tension and bending (flexural) test models by comparing numerical results with similar models from the literature. Following validation, a multi-phase approach modeled NAC and RAC for the bending (flexural) and tension tests, providing a …

Development And Evaluation Of Highly Thixotropic Uhpc Mixtures For Bridge Overlay Applications, Akbota Aitbayeva

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Ultra-high-performance concrete (UHPC) is an advanced construction material renowned for its exceptional strength and durability. However, conventional UHPC is typically self-consolidating, making it unsuitable for bridge deck overlay applications due to challenges posed by potential surface slopes. UHPC overlay construction requires a highly thixotropic material that not only responds well to vibration but also maintains workability over an extended period and remains stable on sloped surfaces. Despite the complex rheological properties of highly thixotropic UHPC, limited testing methods are available to effectively assess the workability and rheology of overlay mixtures. To address this gap, the present study provides a comprehensive …

Exploring Variably Saturated Flow Formulations For Modflow: Implementing A Fully 3d Richards' Equation In Modflow 6, Sebastian Vazquez-Gasty

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This thesis explores the implementation of a fully 3D Richards’ equation solution into MODFLOW 6 to solve for saturated/unsaturated flow. Currently, MODFLOW 6 has limited capability for solving unsaturated zone flow problems by using the Unsaturated Zone Flow (UZF) package, which neglects capillarity and assumes vertical 1-dimensional flow. Various formulations of the Richards’ equation were first evaluated for their strengths and weaknesses. Various numerical solution approaches to Richards’ equation were also studied to understand the robustness and efficiency of different approaches and to select one that would best fit into the MODFLOW 6 framework. The MODFLOW 6 framework was also …

Dynamics Of Flexible Freestanding Structures Under Ground Motion Excitation, Seyed Mohammadreza Farooghi Mehr

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Freestanding structures are characterized by being unattached at the base, exhibiting rigid or flexible motion under ground motion excitation with various potential responses including rocking (rotation at the base about corner points), pure sliding, slide-rocking, and overturning. While rigid freestanding structures have been extensively studied, the behavior of flexible freestanding structures—particularly the interaction between modes involving sliding—remains underexplored. Existing literature has focused on the deformation and rocking motions of flexible freestanding structures through both analytical and experimental approaches, which have shown indications of sliding at the base. These findings highlight the necessity of incorporating sliding motion into analytical models to …

Internet Of Things-Based Automated Solutions Utilizing Machine Learning For Smart And Real-Time Irrigation Management: A Review, Bryan Nsoh, Abia Katimbo, Hongzhi Guo, Derek M. Heeren, Hope Njuki Nakabuye, Xin Qiao, Yufeng Ge, Daran R. Rudnick, Joshua Wanyama, Erion Bwambale, Shafik Kiraga

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This systematic review critically evaluates the current state and future potential of real-time, end-to-end smart, and automated irrigation management systems, focusing on integrating the Internet of Things (IoTs) and machine learning technologies for enhanced agricultural water use efficiency and crop productivity. In this review, the automation of each component is examined in the irrigation management pipeline from data collection to application while analyzing its effectiveness, efficiency, and integration with various precision agriculture technologies. It also investigates the role of the interoperability, standardization, and cybersecurity of IoT-based automated solutions for irrigation applications. Furthermore, in this review, the existing gaps are identified …

Accelerated Bridge Construction (Abc) Decision Tool, Phil Barutha, Marc Maguire, Elio Saldana, Fray F. Pozo-Lora

Nebraska Department of Transportation: Research Reports

This report investigates the creation and assessment of a decision-making tool developed to aid the Nebraska Department of Transportation (NDOT) in determining the suitability of the Accelerated Bridge Construction (ABC) method for bridge replacement projects. The tool utilizes the Analytic Hierarchy Process (AHP) to integrate different criteria, including Average Daily Traffic (ADT), Average Daily Truck Traffic (ADTT), detour time, railroad impact, economy of scale, and the use of typical details, which were found to be paramount in the decision-making process across the state. A sensitivity analysis was conducted to evaluate the tool’s performance and identify the most significant factors influencing …

Effect Of Antioxidant Additives And Recycling Agents On Performance Of Asphalt Binders And Mixtures – Phase Ii, Nitish R. Bastola, Muhammad Ahmad, Mahdieh Khedmati, Jamilla Teixeira, Hamzeh Haghshenas

Nebraska Department of Transportation: Research Reports

The use of reclaimed asphalt pavement (RAP) in combination with recycling agents (RAs) (i.e., rejuvenators or softening agents) has gained significant attention from the pavement industry as a sustainable pavement solution, reducing the carbon footprint of manufactured products through the conservation of energy and reduction on the use of raw materials. Current research has found that RAs can improve RAP recycled asphalt mixture’s cracking resistance, while being capable of maintaining their rutting resistance. However, there are some concerns about the effect of RAs on the moisture damage resistance and the long-term performance (aging) of these additives. The current need is …

Asphalt Binder Laboratory Short-Term Aging - Phase Ii, Farzad Yazdipanah, Ahmad Muhammad, Zahra Kamali Khanghah, Mahdieh Khedmati, Jamilla Teixeira, Mohammad Ghashami, Hamzeh Haghshenas

Nebraska Department of Transportation: Research Reports

This study examined the effectiveness of laboratory short-term aging processes for warm mix asphalt (WMA) binders using response surface methodology (RSM) with various combinations of aging parameters: time, temperature, airflow, and binder weight. The research aimed to enhance understanding of aging parameter efficacy and propose a modified laboratory short-term aging protocol that accurately simulates plant short-term aging in WMA binders. Additionally, the study explored the potential of thermal simulation techniques to model the heat transfer within asphalt mixtures during the compaction procedure. To achieve these goals, three WMA mixtures produced at 135 ºC were collected from plants, and their asphalt …

Targeted Weed Management Of Palmer Amaranth Using Robotics And Deep Learning (Yolov7), Amlan Balabantaray, Shaswati Behera, Cheetown Liew, Nipuna Chamara, Mandeep Singh, Amit J. Jhala, Santosh Pitla

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Effective weed management is a significant challenge in agronomic crops which necessitates innovative solutions to reduce negative environmental impacts and minimize crop damage. Traditional methods often rely on indiscriminate herbicide application, which lacks precision and sustainability. To address this critical need, this study demonstrated an AI-enabled robotic system, Weeding robot, designed for targeted weed management. Palmer amaranth (Amaranthus palmeri S. Watson) was selected as it is the most troublesome weed in Nebraska. We developed the full stack (vision, hardware, software, robotic platform, and AI model) for precision spraying using YOLOv7, a state-of-the-art object detection deep learning technique. The …

Irrigation Pumping Plants: Energy Consumption And Pumping Plant Performance [Class Handout], Derek M. Heeren, Saleh Taghvaeian, Abia Katimbo, Xin Qiao

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigation can be a large contributor to energy consumption on an irrigated farm. It is important to understand factors that impact irrigation energy use and to identify opportunities to reduce energy consumption. This class handout introduces a set of equations for calculating energy consumption for an irrigation pumping plant based on flow conditions and pump efficiency. It also presents typical values for motor performance (including both electric motors and internal combustion engines) in both SI and USCS units. Finally, the handout introduces the concept of a field evaluation of an irrigation pumping plant along with the Nebraska Pumping Plant Performance …

High-Mast Tower Foundation – Phase Ii, Ammar Al Maabreh, Abdelrahman Awawdeh, Marc Maguire, Jay Puckett, Brandon Kreiling

Nebraska Department of Transportation: Research Reports

Challenge: High-mast luminaire supports used in the US transportation sector are typically steel poles that are attached to a baseplate via a butt or socket weld. Many have failed primarily due to fatigue cracking at the weld toe. Significant research in the US improved the fatigue performance of these structures; however, failures still occur due to high-cycle cracking at the weld toes, or at other fatigue-prone details. Additionally, poles are failing in moderate winds that create galloping. Galloping is an aerodynamic phenomenon where the wind excitation frequency matches the pole’s natural frequency creating resonance. The top amplitudes are many times …

Gsp-Ai: An Ai-Powered Platform For Identifying Key Growth Stages And The Vegetative-To-Reproductive Transition In Wheat Using Trilateral Drone Imagery And Meteorological Data, Liyan Shen, Guohui Ding, Robert Jackson, Mujahid Ali, Shuchen Liu, Arthur Mitchell, Yeyin Shi, Xuqi Lu, Jie Dai, Greg Deakin, Katherine Anna Frels, Haiyan Cen, Yufeng Ge, Ji Zhou

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Wheat (Triticum aestivum) is one of the most important staple crops worldwide. To ensure its global supply, the timing and duration of its growth cycle needs to be closely monitored in the field so that necessary crop management activities can be arranged in a timely manner. Also, breeders and plant researchers need to evaluate growth stages (GSs) for tens of thousands of genotypes at the plot level, at different sites and across multiple seasons. These indicate the importance of providing a reliable and scalable toolkit to address the challenge so that the plot-level assessment of GS can be …

Investigation Of Faults In Air-Conditioning Systems In Commercial Buildings: Occurrence, Diagnostic Validation, And Energy Impacts, Yuxuan Chen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In commercial buildings, fault detection and diagnosis (FDD) tools have been developed for detecting and diagnosing faults in building systems, which can provide useful information regarding fault locations and potential causes of faults, so that building operators and facility staff can be notified in time and quickly respond as problems arise. Nowadays, there are many commercial FDD tools available in the market, and these tools have been widely adopted in large- and medium-scale commercial buildings in the United States. Several studies have demonstrated the energy saving potential with the use of FDD in commercial HVAC systems, and one critical aspect …

Long Term Ultrasonic Monitoring And Machine Learning Investigation Of Micro-Crack Damaged Concrete, Yalei Tang

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The thermal modulation method is a recently developed nonlinear ultrasonic technique for evaluating material damage. This method utilizes thermal strain changes resulting from temperature variations to excite the nonlinear behavior of materials and modulate high-frequency ultrasonic waves within them. Its working principle suggests significant potential for application in large-scale concrete structures and in-situ monitoring of real structures. Despite numerous laboratory demonstrations of its effectiveness, several gaps remain before it can be applied to in-service large concrete structures.

This study investigates the potential of the thermal modulation technique for evaluating concrete structures in ambient conditions, addressing key uncertainties for practical implementation. …

Evaluation Of Unreinforced And Geosynthetic-Reinforced Subgrade Material Performance With Large-Scale Tracking Wheel Tests And Dynamic Cone Penetrometer Tests, Kenaz Owusu

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Subgrade has a significant impact on the performance of a pavement as it serves as the foundation layer on which traffic loads are transferred. Many pavement failures can be attributed to weak subgrade strength. The integration of geosynthetics in road pavements has been identified as an effective solution for enhancing subgrade performance to withstand imposed traffic. This study evaluated the performance of unreinforced and geosynthetic-reinforced subgrades in Nebraska to quantify the contribution of geosynthetics to unpaved layer systems.

The strength and stiffness of different soil subgrades were assessed through unconfined compressive strength tests and repeated load triaxial (RLT) tests, which …

Optimized Gadolinium-Do3a Loading In Raftpolymerized Copolymers For Superior Mr Imaging Of Aging Blood–Brain Barrier, Hunter A. Miller, Aaron Priester, Evan T. Curtis, Krista Hilmas, Ashleigh Abbott, Forrest Kievit, Anthony J. Covertine

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The development of gadolinium-based contrast agents (GBCAs) has been pivotal in advancing magnetic resonance imaging (MRI), offering enhanced soft tissue contrast without ionizing radiation exposure. Despite their widespread clinical use, the need for improved GBCAs has led to innovations in ligand chemistry and polymer science. We report a novel approach using methacrylate-functionalized DO3A ligands to synthesize a series of copolymers through direct reversible addition-fragmentation chain transfer (RAFT) polymerization. This technique enables precise control over the gadolinium content within the polymers, circumventing the need for subsequent conjugation and purification steps, and facilitates the addition of other components such as targeting ligands. …

Development Of A Rule-Based Monitoring System For Autonomous Heavy Equipment Safety, Amirpooya Shirazi

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Roadway construction work zones are constantly exposed to interactions among construction equipment, workers, and vehicles. Furthermore, ensuring safety in these areas is considered a challenging task due to the complexity of the environment. As shown in the rising trend of fatal accidents in roadway work zones, current OSHA regulations in construction safety are insufficient in effectively detecting unsafe situations and mitigating the risks. Furthermore, best practices, such as internal traffic control planning (ITCP), exhibit critical limitations requiring continuous monitoring of active work zones as well as adjustments to the site coordination plans due to the dynamic nature of work zone …

Sensitization Of Europium Oxide Nanoparticles Enhances Signal-To- Noise Over Autofluorescence With Time-Gated Luminescence Detection, Hunter Miller, Jessica Q. Wallace, Hui Li, Xing-Zhong Li, Ana De Bettencourt-Dias, Forrest Kievit

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Clinical translation of nanoparticle-based therapeutics has been limited, and a lack of preclinical delivery characterization is partly to blame, limiting our understanding of the mechanisms of failure. The improvement of the preclinical delivery assessment requires nanoparticles with higher detectability. This work focused on the exploration of several aromatic carboxylic ligands (terephthalic acid, quinaldic acid, and kynurenic acid) for the sensitization of europium oxide nanoparticles with a long emission lifetime to overcome cellular autofluorescence, a key confounder of detection in luminescence-based bioimaging. A facile one-pot synthesis and ligand exchange process generated and sensitized ultrasmall Eu₂O₃ cores. As reflected …

A Comprehensive Study On The Impact Of Human Hair Fiber And Millet Husk Ash On Concrete Properties: Response Surface Modeling And Optimization, Naraindas Bheel, Muhammad Alamgeer Shams, Samiullah Sohu, Abdul Salam Buller, Taoufik Najeh, Fouad Ismail Ismail, Omrane Benjeddou

Department of Civil and Environmental Engineering: Faculty Publications

Revolutionizing construction, the concrete blend seamlessly integrates human hair (HH) fibers and millet husk ash (MHA) as a sustainable alternative. By repurposing human hair for enhanced tensile strength and utilizing millet husk ash to replace sand, these materials not only reduce waste but also create a durable, eco-friendly solution. This groundbreaking methodology not only adheres to established structural criteria but also advances the concepts of the circular economy, representing a significant advancement towards environmentally sustainable and resilient building practices. The main purpose of the research is to investigate the fresh and mechanical characteristics of concrete blended with 10–40% MHA as …

Cost Modeling Of Provision C.3 Green Stormwater Infrastructure Requirements For Residential Development In Concord, California, James Henry Mizutani

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

To assist the city of Concord in achieving its housing goals as presented in its general plan, while still meeting the stormwater discharge requirements laid out in the city’s municipal discharge permit, I worked with local developers and consultants to create a spreadsheet modeling tool that allows housing developers to estimate the total cost of green stormwater infrastructure needed to comply with local regulations.

This report contains a summary of the conditions leading to the necessity of this tool, the steps the tool takes that go beyond existing models, a description of how the model operates, instructions on how to …