Engineering Commons^™

Society Dilemma Of Computer Technology Management In Today's World, Iwasan D. Kejawa Ed.D

School of Computing: Faculty Publications

Abstract - Is it true that some of the inhabitants of the world’s today are still hesitant in using computers? Research has shown that today many people are still against the use of computers. Computer technology management can be said to be obliterated by security problems. Research shows that some people in society feel reluctant or afraid to use computers because of errors and exposure of their privacy and their sophistication, which sometimes are caused by computer hackers and malfunction of the computers. The dilemma of not utilizing computer technology at all or, to its utmost, by certain people in …

A Low Jitter And Low Power Electronic Interface For Time-Of-Flight Positron Emission Tomography Silicon Photomultiplier Detectors, Matthew Romer

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

A time-of-flight (TOF) detection system for a silicon photomultiplier (SiPM) is designed for the purpose of improving on existing technology for applications in positron emission tomography, with an emphasis on low power and low timing jitter. A reconstruction algorithm is implemented in Matlab to demonstrate the effect of TOF on the image quality per number of source events, as compared to systems restricted to line-of-response (LOR) data only. A case study is performed on SiPM functionality, behavioral modeling, and contemporary front-end amplification designs for a SiPM detector. A charge sensitive amplifier (CSA) circuit is modified for simultaneous collection of timing …

Learning Domain Invariant Information To Enhance Presentation Attack Detection In Visible Face Recognition Systems, Jennifer Hamblin

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Face signatures, including size, shape, texture, skin tone, eye color, appearance, and scars/marks, are widely used as discriminative, biometric information for access control. Despite recent advancements in facial recognition systems, presentation attacks on facial recognition systems have become increasingly sophisticated. The ability to detect presentation attacks or spoofing attempts is a pressing concern for the integrity, security, and trust of facial recognition systems. Multi-spectral imaging has been previously introduced as a way to improve presentation attack detection by utilizing sensors that are sensitive to different regions of the electromagnetic spectrum (e.g., visible, near infrared, long-wave infrared). Although multi-spectral presentation attack …

The Effect Of Store-To-Store Energy Transfers On The Global Dynamics Of Aircraft, Guilherme Mainieri Eymael, Keegan J. Moore

UNL Student Research Days Posters, Undergraduate

This study analyzes the energy transfer mechanisms when nonlinear devices (stores) are attached to a linear model airplane. For that, a reduced-order model (ROM) was derived to simulate the first two flexible modes of vibration of the primary structure (aircraft) with one store in each wing. Each store can either be locked or unlocked. When locked, it only contributes as mass-effect, and when unlocked, it adds nonlinearity to the system. Simulations were then performed with either both stores locked, one store unlocked, or both stores unlocked. It was found that the attachment of nonlinear stores in the ROM changes the …

Reflection Types And Students’ Viewing Of Feedback In A First-Year Engineering Course Using Standards-Based Grading, Heidi A. Diefes-Dux, Laura M. Cruz Castro

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background: Feedback is one of the most powerful and essential tools for learning and assessment, particularly when it provides the information necessary to close an existing gap between actual and reference levels of performance. The literature on feedback has primarily focused on addressing strategies for providing effective feedback rather than aspects of students’ readiness to engage with feedback. Purpose/Hypothesis: This study investigated whether reflection, as a routine pedagogical intervention grounded in self-regulated learning theory, promotes the frequency with which students view feedback. Design/Method: A quasi-experimental design was employed to examine the relationship between the use of four different reflection types, …

Biomechanical Analysis Of Athletes Sprinting With Varying Degrees Of Resistance, Michaela Ott

Honors Program: Senior Projects (Public)

Utilizing resistance methods for sprinters is a common approach to their training. In this study, six athletes from the University of Nebraska-Lincoln Women’s Track and Field Team ran a series of sprints using a resistance machine to collect data regarding the change in power output, stride length, level of trunk tilt with respect to the ground, and acceleration throughout a distance of ten meters when different amounts of resistant forces were applied to the athlete. It was hypothesized that as resistance increased, power output would increase, stride length would decrease, the runners would become more horizontal resulting in a larger …

Polyaniline/Cobalt Nanoparticle Composite Films, Rifat Mahbub

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Polymer nanocomposites have been gaining attention because of the enhanced properties of the element materials it can offer. These composites have been used in biological sector as well as quantum computing and memory devices. These are also used as different kind of sensors. Polymer composites incorporated with magnetic nanoparticles can modify the magnetic property of the nanoparticles and that has huge potential to be used in different sort of applications.

This work aims to develop a polymeric nanocomposite incorporating a conducting polymer and magnetic nanoparticles. The influence of the conducting polymer on the magnetic property of the nanoparticles was investigated. …

Ultra-Broadband And Polarization-Insensitive Metasurface Absorber With Behavior Prediction Using Machine Learning, Shobhit K. Patel, Juveriya Parmar, Vijay Katkar, Fahad Ahmed Al-Zahrani, Kawsar Ahmed

Department of Mechanical and Materials Engineering: Faculty Publications

The solar spectrum energy absorption is very important for designing any solar absorber. The need for absorbing visible, infrared, and ultraviolet regions is increasing as most of the absorbers absorb visible regions. We propose a metasurface solar absorber based on Ge₂Sb₂Te₅ (GST) substrate which increases the absorption in visible, infrared and ultraviolet regions. GST is a phase-changing material having two different phases amorphous (aGST) and crystalline (cGST). The absorber is also analyzed using machine learning algorithm to predict the absorption values for different wavelengths. The solar absorber is showing an ultra-broadband response covering a 0.2–1.5 …

Seabem: An Artificial Intelligence Powered Web Application To Predict Cover Crop Biomass, Aime Christian Tuyishime, Andrea Basche

Honors Program: Senior Projects (Public)

SEABEM, the Stacked Ensemble Algorithms Biomass Estimator Model, is a web application with a stacked ensemble of Machine Learning (ML) algorithms running on the backend to predict cover crop biomass for locations in Sub-Saharan. The SEABEM model was developed using a previously developed database of crop growth and yield that included site characteristics such as latitude, longitude, soil texture (sand, silt, and clay percentages), temperature, and precipitation. The goal of SEABEM is to provide global farmers, mainly small-scale African farmers, the knowledge they need before practicing and benefiting from cover crops while avoiding the expensive and time-consuming operations that come …

Queueing Theory Model Of Pentose Phosphate Pathway, Sylwester M. Kloska, Krzysztof Pałczyński, Tomasz Marciniak, Tomasz Talaśka, Marissa Miller, Beata J. Wysocki, Paul H. Davis, Tadeusz A. Wysocki

Department of Electrical and Computer Engineering: Faculty Publications

Due to its role in maintaining the proper functioning of the cell, the pentose phosphate pathway (PPP) is one of the most important metabolic pathways. It is responsible for regulating the concentration of simple sugars and provides precursors for the synthesis of amino acids and nucleotides. In addition, it plays a critical role in maintaining an adequate level of NADPH, which is necessary for the cell to fight oxidative stress. These reasons prompted the authors to develop a computational model, based on queueing theory, capable of simulating changes in PPP metabolites’ concentrations. The model has been validated with empirical data …

Protocol To Engineer Nanofilms Embedded Lipid Nanoparticles For Controlled And Targeted Drug Delivery (Nectar), Rashi Porwal, Stephen L. Hayward, Srivatsan Kidambi

Department of Chemical and Biomolecular Engineering: Faculty Publications

We present a protocol to engineer a substrate-mediated delivery platform comprising hyaluronic acid-coated lipid nanoparticles (HALNPs) embedded into polyelectrolyte multilayer (PEM) films. This platform allows controlled spatiotemporal release of lipid nanoparticles (LNP) by embedding them within the polyelectrolyte multilayer films matrix. HALNP conjugate with antibodies also adds the ability for targeted delivery. The use of LNP enables this platform to encapsulate both hydrophobic and hydrophilic drugs. This platform can easily be reproduced and utilized for various biomedical drug delivery applications. For complete details on the use and execution of this protocol, please refer to Hayward et al. (2015, 2016a, 2016b), …

The Effect Of Store-To-Store Energy Transfers On The Global Dynamics Of Aircraft, Guilherme Mainieri Eymael

Honors Program: Senior Projects (Public)

This study analyzes the energy transfer mechanisms when nonlinear devices (stores) are attached to a linear model airplane. For that, a reduced-order model (ROM) was derived to simulate the first two flexible modes of vibration of the primary structure (aircraft) with one store in each wing. Each store can either be locked or unlocked. When locked, it only contributes as mass-effect, and when unlocked, it adds nonlinearity to the system. Simulations were then performed with either both stores locked, one store unlocked, or both stores unlocked. It was found that the attachment of nonlinear stores in the ROM changes the …

An Evaluation Of Tractors Tested At The Nebraska Tractor Test Lab And The Effect Of Epa Emission Standards Based Upon Average Pto Horsepower And Fuel Efficiency, Dalton Erickson

Honors Program: Senior Projects (Public)

Newly released tractor models are tested to ensure they meet advertising claims. This thesis utilizes tractor test data to analyze performance trends in tractors based upon their power take off (PTO) horsepower and fuel efficiency and it evaluates how the average fuel efficiency of tractors was affected by the introduction of emission standards by the United States Environmental Protection Agencies. In conclusion, tractors have shown continuous improvement and growth in both fuel efficiency and PTO horsepower, and emission standards have had a small, positive effect on tractors’ average fuel efficiency.

Development Of Controller Area Network Bus Programming For Quarter-Scale Tractor Pulling Sled, Brittani Wacker

Honors Program: Senior Projects (Public)

Usage of Controller Area Network (CAN) technology has allowed for advancements in many industries, including agriculture. Most importantly, its application is useful for refining data acquisition methods. With support from the Quarter-scale Tractor Design Team at UNL, this project united a CAN bus with the team’s current tractor pulling sled. The objectives were to install new instrumentation needed for the CAN bus and to program the updated system utilizing CAN data. The program needed to give the pulling sled functionality and the ability to read and log important pulling data. These goals were all accomplished by implementing new sensors, coding …

Design Of A Week-Long Introduction To Engineering Summer Camp To Increase Interest And Eagerness Of Stem In Young Children, Beth Cannon

Honors Program: Senior Projects (Public)

For this creative project, a one-week camp curriculum was designed for elementary students (Grades 3-5) to introduce engineering. This work includes a rationale and camp curriculum. The rationale describes the research-based design of the curriculum. It outlines engineering basics and why and how to teach engineering to young students. The curriculum intends to introduce engineering to young children and excite the possibility of a future career. The following engineering disciplines are presented throughout the week of camp: mechanical, environmental, civil, electrical, and chemical. The first day of camp focuses on the basics of engineering. Following that, each day of camp …

Closed-Loop Control Of Meltpool Temperature In Directed Energy Deposition, Ziyad M. Smoqi, Ben Bevans, Aniruddha Gaikwad, James Craig, Alan Abul-Haj, Brent Roeder, Bill Macy, Jeffrey E. Shield, Prahalada K. Rao

Department of Mechanical and Materials Engineering: Faculty Publications

The objective of this work is to mitigate flaw formation in powder and laser-based directed energy deposition (DED) additive manufacturing process through close-loop control of the meltpool temperature. In this work, the meltpool temperature was controlled by modulating the laser power based on feedback signals from a coaxial two-wavelength imaging pyrometer. The utility of closed-loop control in DED is demonstrated in the context of practically inspired trapezoid-shaped stainlesssteel parts (SS 316L). We demonstrate that parts built under closed-loop control have reduced variation in porosity and uniform microstructure compared to parts built under open-loop conditions. For example, post-process characterization showed that …

Impacts Of Temperature And Carbon Dioxide On Boro Rice Production, Sabiha Ferdous

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

There are different anticipated impacts of climate change (CC) on agriculture all over the world. Bangladesh as a developing country has potential vulnerability and negative impacts on CC. This change in meteorological parameters creates negative impacts on agricultural production which is a threat to food security and economic development. The country has recently achieved food security in rice which is mainly due to increased yields and area coverage of irrigated dry season (Boro) rice over the last decades. It is necessary to predict the future Boro rice production in accordance with CC as well as take supplementary actions to ensure …

Biogeosciences Perspectives On Integrated, Coordinated, Open, Networked (Icon) Science, D. Dwivedi, A. L.D. Santos, M. A. Barnard, T. M. Crimmins, A. Malhotra, K. A. Rod, K. S. Aho, S. M. Bell, B. Bomfim, F. Q. Brearley, H. Cadillo-Quiroz, J. Chen, C. M. Gough, E. B. Graham, C. R. Hakkenberg, L. Haygood, G. Koren, E. A. Lilleskov, L. K. Meredith, S. Naeher, Z. L. Nickerson, O. Pourret, H. S. Song, M. Stahl, N. Taş, R. Vargas, S. Weintraub-Leff

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This article is composed of three independent commentaries about the state of Integrated, Coordinated, Open, Networked (ICON) principles in the American Geophysical Union Biogeosciences section, and discussion on the opportunities and challenges of adopting them. Each commentary focuses on a different topic: (a) Global collaboration, technology transfer, and application (Section 2), (b) Community engagement, community science, education, and stakeholder involvement (Section 3), and (c) Field, experimental, remote sensing, and real-time data research and application (Section 4). We discuss needs and strategies for implementing ICON and outline short- and long-term goals. The inclusion of global data and international community engagement are …

Land Use Influences The Composition And Antimicrobial Effects Of Propolis, Amara J. Orth, Emma H. Curran, Eric J. Haas, Andrew C. Kraemer, Audrey M. Anderson, Nicholas J. Mason, Carol A. Fassbinder-Orth

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Honey bee propolis is a complex, resinous mixture created by bees using plant sources such as leaves, flowers, and bud exudates. This study characterized how cropland surrounding apiaries affects the chemical composition and antimicrobial effects of propolis. The chemical composition and compound abundance of the propolis samples were analyzed using Gas Chromatography- Mass Spectrometry (GC-MS) and the antimicrobial effects were analyzed using the 50% minimum inhibitory concentration (MIC₅₀) assay against four relevant bee pathogens, Serratia marcescens, Paenibacillus larvae, Lysinibacillus sphaericus, and Klebsiella pneumoniae. Propolis composition varied significantly with apiary, and cropland coverage predicted mean sum abundance of …

Precipitation And Temperature Extremes And Association With Large-Scale Climate Indices: An Observational Evidence Over India, S Rehana, Pranathi Yeleswarapu, Ghouse Basha, Francisco Munoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Climate change exposes more frequent natural hazards and physical vulnerabilities to the built and natural environments. Extreme precipitation and temperature events will have a significant impact on both the natural environment and human society. However, it is unclear whether precipitation and temperature extremes increase physical vulnerabilities across scales and their links with large-scale climate indices. This study investigates the relationship between precipitation and temperature extremes, as recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI), and large scale climatological phenomenon indices (Indian Summer Monsoon Index (ISMI), Arctic Oscillation (AO), and North Atlantic Oscillation (NAO)), using India as …

Ahp Based Multi Criteria Decision Analysis Of Success Factors To Enhance Decision Making In Infrastructure Construction Projects, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei

Durham School of Architectural Engineering and Construction: Faculty Publications

The study presents analytical data-based multi-criteria approach of critical success factors of infrastructure construction projects analyzed in the Ethiopian construction industry. This multi-criteria technique helps to improve the decision capabilities and ultimate performance of construction processes in various low-income countries of the East African region. The aim of this paper is to establish a logical relationship and interdependencies of success-related factors for enhancing decision making for various project teams and identify priorities while taking into account all known construction organizational constraints. A structured hierarchical matrix was developed based on a pre-identified success-related factors, and initially evaluated by experienced professionals as …

Developing Metrics For Nasa Earth Science Interdisciplinary Data Products And Services, Zhong Liu, Chung-Lin Shie, Anthony J. Ritrivi, Guang-Dih Lei, Gary T. Alcott, Mary Greene, James Acker, Jennifer C. Wei, David J. Meyer, Angela Li, Atheer F. Al-Jazrawi

Copyright, Fair Use, Scholarly Communication, etc.

Metrics are measures that are able to produce quantifiable information. There are many applications of metrics in Earth science data and services; for example, metrics are frequently used to track service performance and progress. In short, developing, collecting and analyzing metrics are essential activities to better support Earth science research, applications, and education.

As one of the largest repositories of Earth science data in the world, NASA’s Earth Science Data and Information System (ESDIS) Project supports twelve Distributed Active Archive Centers (DAACs). Standard metrics have been developed by the ESDIS Metrics System (EMS). These metrics are collected and analyzed routinely …

A Precise Dispenser Design For Canine Cognition Research, Walker Arce, Jeffrey R. Stevens

Department of Electrical and Computer Engineering: Faculty Publications

Some forms of canine cognition research require a dispenser that can accurately dispense precise quantities of treats. When using off-the-shelf or retrofitted dispensers, there is no guarantee that a precise number of treats will be dispensed. Often, they will over-dispense treats, which may not be acceptable for some tasks. Here we describe a 3D-printed precise treat dispenser with a 59-treat capacity driven by a stepper motor drive and controlled by an integrated Raspberry Pi. The dispenser can be built for less than 200 USD and is fully 3D printable. While off-the-shelf dispensers can result in an error rate of 20–30%, …

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 …

Conceptual Framework To Integrate Economic Drivers Of Decision Making For Technology Adoption In Agriculture, Thiago L. Romanelli, Francisco Muñoz-Arriola, Andre F. Colaço

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study evaluates how much technology adoption could cost in a variety of crop-production scenarios. Cost-reduction simulations consider scenarios of higher input use efficiency such as reducing the usage of diesel, labor, irrigation, fertilizer, herbicide, and seed, among others. The scenarios aim to increase yields by integrating the effect of each input-reduction on the total operating costs. Agricultural production estimates for Nebraska in the US indicates that a technology that saves 1% of diesel is cost-effective, costing between USD 0.15/ha and USD 0.32/ha (for corn). Improvements on input use efficiency should be prioritized to incentivize technology development and adoption. This …

Maize Response To Coupled Irrigation And Nitrogen Fertilization Under Center Pivot, Subsurface Drip And Surface (Furrow) Irrigation: Growth, Development And Productivity, Suat Irmak, Ali T. Mohammed, Meetpal S. Kukal

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water availability and water quality problems negatively impact agricultural productivity due to improper nitrogen (N) and irrigation management, which can also negatively affect environmental services. Coupled irrigation and N management practices must be developed and practiced for alleviating these challenges. Investigating crop growth and development and yield response to coupled irrigation and N management under different irrigation methods can aid in developing optimum agronomic management practices to enhance crop production efficiency. Field experiments were conducted in 2016 and 2017 growing seasons to measure and compare maize (Zea mays L.) grain yield, leaf area index (LAI), plant height (and their …

Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu

Department of Civil and Environmental Engineering: Faculty Publications

Coda wave interferometry (CWI) has been used to measure the relative wave-velocity change (dV/V) caused by small changes in materials. This study uses the stretching processing technique which has been used for CWI analysis to investigate velocity changes of direct longitudinal (P) wave, direct shear (S) wave, and coda wave in concrete by choosing different time windows of ultrasonic signals. It is found that the obtained wave-velocity change depends on the time window position, because the relative contribution of P wave and S wave is different in each signal window. This paper presents three experimental scenarios of velocity …

Secondary Science Teachers’ Curricular Use Of Ngss Engineering Practices, Elizabeth Hasseler, Amy Tankersley, Ana M. Rivero, Lyrica L. Lucas, Elizabeth B. Lewis

Department of Teaching, Learning, and Teacher Education: Faculty Publications

We investigated how often teachers integrated engineering into science lessons to address Next Generation Science Standards (NGSS) performance expectations using data from a multi-year study of secondary science teachers. Only 7.14% of middle school (MS) lessons contained engineering practices. Engineering was included in lessons for students to apply or support the learning of scientific content.

Presider: Amy Tankersley

Genome Structure And Evolutionary History Of Frankincense Producing Boswellia Sacra, Abdul Latif Khan, Ahmed Al-Harrasi, Jin-Peng Wang, Sajjad Asaf, Jean-Jack Riethoven, Tariq Shehzad, Chia-Sin Liew, Xiao-Ming Song, Daniel P. Schachtman, Chao Liu, Ji-Gao Yu, Zhi-Kang Zhang, Fan-Bo Meng, Jia-Qing Yuan, Chen-Dan Wei, He Guo, Xuewen Wang, Ahmed Al-Rawahi, In-Jung Lee, Jeffrey L. Bennetzen, Xi-Yin Wang

Nebraska Center for Biotechnology: Faculty and Staff Publications

Boswellia sacra Flueck (family Burseraceae) tree is wounded to produce frankincense. We report its de novo assembled genome (667.8 Mb) comprising 18,564 high-confidence protein-encoding genes. Comparing conserved single-copy genes across eudicots suggest >97% gene space assembly of B. sacra genome. Evolutionary history shows B. sacra gene-duplications derived from recent paralogous events and retained from ancient hexaploidy shared with other eudicots. The genome indicated a major expansion of Gypsy retroelements in last 2 million years. The B. sacra genetic diversity showed four clades intermixed with a primary genotype—dominating most resin-productive trees. Further, the stemtranscriptome revealed that wounding concurrently activates phytohormones signaling, …

Characterizing Isoform Switching Events In Esophageal Adenocarcinoma, Yun Zhang, Katherine M. Weh, Connor L. Howard, Jean-Jack Riethoven, Jennifer L. Clarke, Kiran H. Lagisetty, Jules Lin, Rishindra M. Reddy, Andrew C. Chang, David G. Beer, Laura A. Kresty

Nebraska Center for Biotechnology: Faculty and Staff Publications

Isoform switching events with predicted functional consequences are common in many cancers, but characterization of switching events in esophageal adenocarcinoma (EAC) is lacking. Next-generation sequencing was used to detect levels of RNA transcripts and identify specific isoforms in treatment- naïve esophageal tissues ranging from premalignant Barrett’s esophagus (BE), BE with low- or high-grade dysplasia (BE.LGD, BE.HGD), and EAC. Samples were stratified by histopathology and TP53 mutation status, identifying significant isoform switching events with predicted functional consequences. Comparing BE.LGD with BE.HGD, a histopathology linked to cancer progression, isoform switching events were identified in 75 genes including KRAS, RNF128, and WRAP53. Stratification …