Engineering Commons^™

Analysis Of Breath-Holding Index As An Assessment Of Cerebrovascular Reactivity, Allison P. Porter, Madison Burger, Mohammed Alwatban, Benjamin Hage, Greg Bashford

UCARE: Research Products

Cerebrovascular reactivity (CVR) is a key factor in regulating blood flow into the brain, and a marker for vascular disease. If the brain's regulatory system is not working, a patient may be in serious trouble. Testing of CVR is one method of assessing the brain's regulatory capabilities. Transcranial Doppler ultrasound (TCD) is one tool to measure CVR. In this method, carbon dioxide in the blood is transiently increased (such as with the holding of breath), and the resulting blood flow in the brain is measured. In this study, we are going to measure the variability of the breathholding index.

Within …

Circle Of Willis Model For Transcranial Doppler Ultrasound Training, Conner J. Beyersdorf, Ben Hage, Greg Bashford

UCARE: Research Products

Transcranial Doppler (TCD) ultrasound is a technique involving the use of high frequency transmitters to measure intracranial blood flow. The brain is supplied by blood in an arterial anastomosis called the Circle of Willis. Using TCD ultrasound on the circle is difficult and requires practice and teaching. A functional model of the Circle of Willis could prove to be a valuable teaching tool. Through the use of AutoCAD and 3D printing software, an anatomically accurate model was created and set in gelatin phantom inside of a plastic skull. Milk was pumped through the model with a peristaltic pump to simulate …

Drag Reduction Using Femtosecond Laser Surface Processing: Experimental Setup, Derek Wallin, Henry Ems, Craig Zuhlke, Dennis R. Alexander, George Gogos, Sidy Ndao

UCARE: Research Products

The experimental setup for developing a system to test the drag effects of different superhydrophorbicities. This is used to revise the current Moody Chart and redefine fluid drag in a pipe.

Fluid drag reduction is important in many applications such as reducing the power requirement to pump a fluid through a channel or pipe. The Center for Electro-Optics and Functionalized Surfaces (CEFS) at the University of Nebraska – Lincoln uses a femtosecond laser to functionalize 304 stainless Steel to become superhydrophilic or superhydrophobic The Processing produces microscale and nanoscale surface roughness that when treated with siloxanes becomes superhydrophobic. Small vortices …

Investigation Of A Nanoparticle Delivery System For Micronutrients In Corn, Zully Perez Sierra, Zachary P. Stewart, Hendrik J. Viljoen

UCARE: Research Products

Pheroid Nanoparticle Delivery System1 • Cost effective for plant applications • Safe – multi-lamellar lipid system derived mostly from soybeans • Versatile – payloads delivered range from micronutrients to antibiotics Micronutrient Deficiency • Caused by the immobility of micronutrients through the plant. • Leads to malnutrition children in poor countries2 • As fertilizers deliver nutrients, only small percentage obtained by plant. Purpose of Nanoparticle Delivery System • Increase plant micronutrient content and yield • Reduces the effects of run-of, overuse and pollution Other Nano-Fertilizer Trials • Desert plant results – in a foliar application versus irrigation application, the foliar nano-fertilizer …

Development Of A Robust Setup For The Study Of Wetting Characteristics Of Low Melting Point Metals, John D. Casias, Ethan Allan Davis, Sidy Ndao

UCARE: Research Products

• Energy use is very inefficient

• Approx. 60% rejected mostly in the form of waste heat

• Low melting point metals are promising for applications in thermal energy management, conversion, and storage

Exploring Large-Scale Parameterization Of Irrigation In The Northern High Plains, Mitch Maguire, Daniel Rico, Katherine Smith, Francisco Munoz-Arriola

UCARE: Research Products

Research Question – Objective - Hypothesis

How does irrigation respond to the demands of Crop Irrigation Requirements under extreme hydrometeorological events?

Implement a parameterization of irrigation into the land surface hydrology model VIC.

Changes in evapotranspiration (ET) will be more conspicuous during dry years, highlighting the limiting role of soil moisture in the model.

Exploring Oculomotor Trends In Collegiate Athletes, Brett Whorley, Julie A. Honaker

UCARE: Research Products

Collaborative efforts to improve athlete safety without significantly hindering the rules of the games aim to develop a novel system to better measure and diagnose concussions. Provided that common signs of concussions include blurred vision, distant gaze, and dizziness, the Dizziness and Balance Disorders Lab at UNL believes that the simple oculomotor exam studied in this project may be applied to this procedure. Within the broader goal to better understand the causes, signs, symptoms, and prognosis of concussions, researchers desired to further investigate the results of this oculomotor test. The aim was to identify and interpret correlations between collegiate athlete …

Ionic Driven Embedment Of Hyaluronic Acid Coated Liposomes In Polyelectrolyte Multilayer Films For Local Therapeutic Delivery, Stephen Lawrence Hayward, David Francis, Matthew J. Sis, Srivatsan Kidambi

UCARE: Research Products

The ability to control the spatial distribution and temporal release of a therapeutic remains a central challenge for biomedical research. Here, we report the development and optimization of a novel substrate mediated therapeutic delivery system comprising of hyaluronic acid covalently functionalized liposomes (HALNPs) embedded into polyelectrolyte multilayer (PEM) platform via ionic stabilization. The PEM platform was constructed from sequential deposition of Poly-LLysine (PLL) and Poly(Sodium styrene sulfonate) (SPS) “(PLL/SPS)4.5” followed by adsorption of anionic HALNPs. An adsorption affinity assay and saturation curve illustrated the preferential HALNP deposition density for precise therapeutic loading. (PLL/SPS)2.5 capping layer on top of the deposited …

Design And Testing Of Robotic Capsule Biosensors In The Small Intestine, Zachary Bram

Robotics and Mechanical Systems Design

Biosensors are a tool that is growing in usage and is sought out by doctors and patients alike for being a non-invasive method to monitor health. The data that can be collected from these sensors can be analyzed by doctors that are away from patients, or even by patients that do not have the ability to see a doctor. The purpose of this work is to design and test a biosensor capsule that can attach itself to the inner wall of the small intestine for a short period of time before exiting the body. This research project was a continuation …

Error Mitigation In Rssi-Based Fingerprinting Localization Using Multiple Communication Channels, Francisco Javier Mora-Becerra

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

Location data from radio signal strength indication (RSSI) based wireless networks has been used in various applications such as creating smart home behavioral monitoring systems, tracking health care workers for the spread of hospital-associated infections, and providing location-aware tour guide systems. Because RSSI-based systems are inexpensive and can be used with most wireless devices without requiring additional hardware, they are a popular choice for localization. Unfortunately, multipath fading dramatically degrades the performance of an RSSI-based system's ability to locate a target indoors. This thesis endeavors to reduce localization error for RSSI-based fingerprinting localization systems in an indoor environment through frequency …

Cable-To-Post Attachments For Use In Non-Proprietary High-Tension Cable Median Barrier – Phase Ii, Scott K. Rosenbaugh, Robert W. Bielenberg, Jessica L. Lingenfelter, Ronald K. Faller, John D. Reid, Karla A. Lechtenberg

Nebraska Department of Transportation: Research Reports

The objective of this study was to reevaluate and improve the existing cable-to-post attachment hardware that is utilized in the non-proprietary cable barrier being developed at MwRSF. The study focused on redesigning the bolted, tabbed bracket (V10) to eliminate the bolt, reduce the number of components per bracket, eliminate the need for tools during installation, and reduce the number of small parts. Three attachment concepts were selected for evaluation through dynamic testing: (1) the key plate attachment; (2) the wire lock pin attachment; and (3) the pinned back attachment. Each attachment prototype was subjected to two vertical and two lateral …

Estimating Evapotranspiration Of An Apple Orchard Using A Remote Sensing-Based Soil Water Balance, Magali Odi-Lara, Isidro Campos, C.M.U. Neale, Samuel Ortega-Farías, Carlos Poblete-Echeverria, Claudio Balbontín, Alfonso Calera

Daugherty Water for Food Global Institute: Faculty Publications

The main goal of this research was to estimate the actual evapotranspiration (ETc) of a drip-irrigated apple orchard located in the semi-arid region of Talca Valley (Chile) using a remote sensing-based soil water balance model. The methodology to estimate ETc is a modified version of the Food and Agriculture Organization of the United Nations (FAO) dual crop coefficient approach, in which the basal crop coefficient (Kcb) was derived from the soil adjusted vegetation index (SAVI) calculated from satellite images and incorporated into a daily soil water balance in the root zone. A linear relationship between the Kcb and SAVI was …

Predicting Construction Labor Productivity With Bayesian Belief Networks, Ayoub Hazrati

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

Construction labor productivity plays an important role in labor intensive projects. Therefore, increasing construction labor productivity is a vital task to decrease a project’s cost (time). The primary goal of this research is to investigate the feasibility of developing a comprehensive causal model that can predict construction labor productivity for various project’s situations, such as existence of “Adverse Weather,” “Changes,” “Working Overtime,” etc., while considering uncertainty. It is found that Bayesian Belief Networks (BBNs) is the best approach that can model causal relationships among different factors while considering uncertainty, simultaneously.

Developing a BBNs model requires to extract its structure and, …

Evaluation Of Lightweight Pieces In Aggregates, Mark Lindemann, Doug Macke, Jim Wilken, John Ebito, Mark Hassler, Lieska Halsey, Bob Seger

Nebraska Department of Transportation: Research Reports

Nebraska Department of Roads (NDOR) Material and Research (M&R) Division started an evaluation to determined injurious deleterious lightweight pieces of aggregate from a dry pit location, as a result of field observations from a project stock pile. This brief summary presents the field observation and laboratory testing evaluations to determine the percent of lightweight pieces in aggregate.

Evaluation Of Lightweight Pieces In Aggregates, Mark Lindemann, Doug Macke, Jim Wilken, John Ebito, Mark Hassler, Lieska Halsey, Bob Seger

Nebraska Department of Transportation: Research Reports

No abstract provided.

Active Traffic Management Case Study: Phase 1, Anuj Sharma, Shuo Wang, Aemal Khattak

Nebraska Department of Transportation: Research Reports

This study developed a systematic approach for using data from multiple sources to provide active traffic management solutions. The feasibility of two active traffic management solutions is analyzed in this report: ramp-metering and real-time crash risk estimation and prediction. Using a combined dataset containing traffic, weather, and crash data, this study assessed crash likelihood on urban freeways and evaluated the economic feasibility of providing a ramp metering solution. A case study of freeway segments in Omaha, Nebraska, was conducted. The impact of rain, snow, congestion, and other factors on crash risk was analyzed using a binary probit model, and one …

Midwest Guardrail System (Mgs) With An Omitted Post, Jessica L. Lingenfelter, Scott Rosenbaugh, Robert W. Bielenberg, Karla A. Lechtenberg, Ronald K. Faller, John D. Reid

Nebraska Department of Transportation: Research Reports

The objective of this research study was to evaluate the MGS (31” tall W-beam guardrail) with an omitted post according to the safety performance criteria provided in MASH. A single full-scale crash test was conducted with the 2270P pickup truck in accordance with MASH test no. 3-11. The small car test, test no. 3-10, was deemed unnecessary as the pickup truck test would result in higher rail loads, a greater propensity for rail rupture, and a greater risk of failure. The test installation utilized standard 6-ft (1.8-m) long steel guardrail posts with 12-in. (305-mm) deep blockouts. A single post was …

Four Billion People Facing Severe Water Scarcity, Mesfin Mekonnen, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Freshwater scarcity is increasingly perceived as a global systemic risk. Previous global water scarcity assessments, measuring water scarcity annually, have underestimated experienced water scarcity by failing to capture the sea- sonal fluctuations in water consumption and availability. We assess blue water scarcity globally at a high spatial resolution on a monthly basis. We find that two-thirds of the global population (4.0 billion people) live under conditions of severe water scarcity at least 1 month of the year. Nearly half of those people live in India and China. Half a billion people in the world face severe water scarcity all year …

Detecting Faults In Turbine Generators, Wei Qiao, Xiang Gong

Department of Electrical and Computer Engineering: Faculty Publications

Turbine generator faults can be detected by receiving a current signal from the turbine generator, and synchronously sampling the current signal to obtain a set of current signal samples that are evenly spaced in the phase domain, in which phase differences between adjacent current signal samples in the set of current signal samples are substantially the same. The process includes generating a frequency spectrum of the current signal samples, identifying one or more excitations in the frequency spectrum, and detecting a fault in the turbine generator based on the one or more excitations in the frequency spectrum.

A Five-Year Performance Review Of Field-Scale, Slow-Release Permanganate Candles With Recommendations For Second-Generation Improvements, Mark Christenson, Ann Kambhu, James Reece, Steve D. Comfort, Laurie Brunner

Nebraska Water Center: Faculty Publications

In 2009, we identified a TCE plume at an abandoned landfill that was located in a low permeable siltyclay aquifer. To treat the TCE, we manufactured slow-release potassium permanganate cylinders (oxidant candles) that had diameters of either 5.1 or 7.6 cm and were 91.4 cm long. In 2010, we compared two methods of candle installation by inserting equal masses of the oxidant candles (7.6-cm vs 5.1-cm dia). The 5.1-cm dia candles were inserted with direct-push rods while the 7.6-cm candles were housed in screens and lowered into 10 permanent wells. Since installation, the 7.6-cm oxidant candles have been refurbished approximately …

Airborne Lidar Acquisition, Post-Processing And Accuracy-Checking For A 3d Webgis Of Copan, Honduras, Jennifer Von Schwerin, Heather Richards-Rissetto, Fabio Remondino, Maria Grazia Spera, Michael Auer, Nicolas Billen, Lukas Loos, Laura Stelson, Markus Reindel

Department of Anthropology: Faculty Publications

Archaeological projects increasingly collect airborne LiDAR data to use as a remote sensing tool for survey and analysis. Publication possibilities for LiDAR datasets, however, are limited due to the large size and often proprietary nature of the data. Fortunately, web-based, geographic information systems (WebGIS) that can securely manage temporal and spatial data hold great promise as virtual research environments for working with and publishing LiDAR data. To test this and to obtain new data for archaeological research, in 2013, the MayaArch3D Project (www.mayaarch3d.org) collected LiDAR data for the archaeological site of Copan, Honduras. Results include: 1) more accurate archaeological maps, …

Glucocorticoid Cell Priming Enhances Transfection Outcomes In Adult Human Mesenchymal Stem Cells, Abby M. Kelly, Sarah A. Plautz, Janos Zempleni, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Human mesenchymal stem cells (hMSCs) are one of the most widely researched stem cell types with broad applications from basic research to therapeutics, the majority of which require introduction of exogenous DNA. However, safety and scalability issues hinder viral delivery, while poor efficiency hinders nonviral gene delivery, particularly to hMSCs. Here, we present the use of a pharmacologic agent (glucocorticoid) to overcome barriers to hMSC DNA transfer to enhance transfection using three common nonviral vectors. Glucocorticoid priming significantly enhances transfection in hMSCs, demonstrated by a 3-fold increase in efficiency, 4–15-fold increase in transgene expression, and prolonged transgene expression when compared …

Ecosystem Evapotranspiration: Challenges In Measurements, Estimates, And Modeling, D.M. Amatya, Suat Irmak, P. Gowda, G. Sun, J.E. Nettles, K.R. Douglas-Mankin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Evapotranspiration (ET) processes at the leaf to landscape scales in multiple land uses have important controls and feed backs for local, regional, and global climate and water resource systems. Innovative methods, tools, and technologies for improved understanding and quantification of ET and crop water use are critical for adapting more effective management strategies to cope with increasing demand for freshwater resources under global climate change. This article introduces an ASABE Special Collection of 12 articles on ET monitoring and modeling research for multiple land uses and scales. The collection focuses on recent advances in four critical topical areas: (1) reference …

Wireless Communication In Data Centers: A Survey, Abdelbaset S. Hamza, Jitender Deogun, Dennis R. Alexander

School of Computing: Faculty Publications

Data centers (DCs) is becoming increasingly an integral part of the computing infrastructures of most enterprises. Therefore, the concept of DC networks (DCNs) is receiving an increased attention in the network research community. Most DCNs deployed today can be classified as wired DCNs as copper and optical fiber cables are used for intra- and inter-rack connections in the network. Despite recent advances, wired DCNs face two inevitable problems; cabling complexity and hotspots. To address these problems, recent research works suggest the incorporation of wireless communication technology into DCNs. Wireless links can be used to either augment conventional wired DCNs, or …

Method For Hyper-Polarizing Nuclear Spns At Arbtrary Magnetic Felds, Carlos A. Meriles, Daniela Pagliero, Abdelghani Laraoui

Department of Mechanical and Materials Engineering: Faculty Publications

A method of dynamically polarizing the nuclear spin host of nitrogen-vacancy (NV) centers in diamond is provided. The method uses optical, microwave and radio-frequency pulses to recursively transfer spin polarization from the NV electronic spin. Nitrogen nuclear spin initialization approaching 80% at room temperature is demonstrated both in ensemble and single NV centers without relying on level anti-crossings. This makes the method applicable at arbitrary magnetic fields.

Case Study Of Quantifying Energy Loss Through Ceiling-Attic Recessed Lighting Fixtures Through 3d Numerical Simulation, Ri Na, Shengmao Lin, Zhigang Shen, Linxia Gu

Durham School of Architectural Engineering and Construction: Faculty Publications

Air leakage through improperly installed recessed lighting fixtures has been identified as a common issue causing extra energy consumption of residential buildings. However, little quantitative study was found in this area. In this paper, a preliminary evaluation of the magnitude of such energy loss was conducted by numerical simulations using 3 dimensional transient computational fluid dynamics (CFD) model. A typical layout of recessed lighting fixtures was used in this case study with boundary conditions in four different seasons, which were obtained from past measured roof/attic temperature data sets. The results of the numerical simulations indicate that leakage of recessed lighting …

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Yun Zhang, Yuping Zhang, J. Brett Sallach

Nebraska Water Center: Faculty Publications

A total of 59 papers published in 2015 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Steroid Hormones, Pharmaceutical Contaminants, Transformation Products, and “Antibiotic Resistance, Drugs, Bugs and Genes”.

Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson

School of Natural Resources: Faculty Publications

Green leaf area index (LAI) provides insight into the productivity, physiological and phenological status of vegetation. Measurement of spectral reflectance offers a fast and nondestructive estimation of green LAI. A number of methods have been used for the estimation of green LAI; however, the specific spectral bands employed varied widely among the methods and data used. Our objectives were (i) to find informative spectral bands retained in three types of methods, neural network (NN), partial least squares (PLS) regression and vegetation indices (VI), for estimating green LAI in maize (a C4 species) and soybean (a C3 species); (ii) to assess …

Recent Morphodynamic Evolution Of The Largest Uninhibited Island In The Yangtze (Changjiang) Estuary During 1998-2014: Influence Of The Anthropogenic Interference, Wen Wei, Xuefei Mei, Zhijun Dai, Zhenghong Tang

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Estuarine geomorphology worldwide has greatly changed in the Anthropocene due to intensive human inferences in river basin and within estuary, which has received increasing global concerns. Here, recent morphodynamic evolution of Jiuduan Shoal (JDS), the largest uninhabited island in the Yangtze (Changjiang) Estuary, and associated controlling factors were analyzed based on unique high-resolution seasonal-surveyed bathymetric data during 1998–2014. It can be indicated that JDS presents novel 12 and 48 months fluctuations though significant accretion was detected on high flats above −2 m. Meanwhile, morphodynamic evolution of JDS during 1998–2014 was divided into three stages: significant siltation on land-ward half of …

A Compact To Revitalise Large-Scale Irrigation Systems Using A Leadership-Partnership-Ownership 'Theory Of Change', Bruce Lankford, Ian Makin, Nathanial Matthews, Peter G. Mccornick, Andrew Noble, Tushaar Shah

Daugherty Water for Food Global Institute: Faculty Publications

In countries with transitional economies such as those found in South Asia, large-scale irrigation systems (LSIS) with a history of public ownership account for about 115 million ha (Mha) or approximately 45% of their total area under irrigation. In terms of the global area of irrigation (320 Mha) for all countries, LSIS are estimated at 130 Mha or 40% of irrigated land. These systems can potentially deliver significant local, regional, and global benefits in terms of food, water and energy security, employment, economic growth, and ecosystem services. For example, primary crop production is conservatively valued at about US$355 billion. However, …