Engineering Commons^™

Scaffold And Tissue Based Therapies To Improve Skeletal Muscle Regeneration After Volumetric Muscle Loss, Benjamin Kasukonis

Graduate Theses and Dissertations

Volumetric muscle loss (VML) is an injury to skeletal muscle characterized by a loss of more than 20% of a muscles volume. The combination of the bulk loss of tissue, transection and separation of myofibers proximal and distal to the injury, loss of innervation and blood supply, and the depletion of muscle progenitor cells results in permanent fibrosis and functional deficits due to loss of contractile tissue. Scaffolds, cells, and engineered constructs have been explored as potential therapeutic interventions to induce myogenesis at the site of a VML injury in animal models, in addition to limited clinical trials. This dissertation …

Removal Of Carboxylic Acids And Water From Pyrolysis Oil, George Alexander Marshall

Graduate Theses and Dissertations

Over 70% of the world’s energy consumption is provided by fossil fuels and with those reserves depleting at a fast rate, alternative energy sources or methods are needed to support the world’s energy needs. This research was done in an attempt to make it more economically feasible to produce fuel products, such as bio-diesel, from the upgrading of bio-oil obtained from the pyrolysis of biomass waste material such as sawdust. The high water and oxygenated compound content of bio-oil make it undesirable for fuel use; however, two methods involving surface modified commercial membranes were utilized in hopes of overcoming these …

Structure-Property Relationships Of Polyisobutylene-Block-Polyamide Thermoplastic Elastomers, Morgan Dunn Heskett

Master's Theses

Thermoplastic elastomers (TPEs) are a class of polymer fit for a wide variety of applications due to their customizability. In the synthesis of these types of materials, an elastically-performing polymer, deemed the “soft block,” is combined with a stiffer “hard block” polymer, each of which can be selected based on their own specific properties in order to achieve desired material behavior in the final copolymer. Recently, the use of polyisobutylene as a soft block in combination with a polyamide hard block has been investigated for use in TPE synthesis. While the material showed some promising behavior, many properties were still …

M049 Effects Of Compaction And Soil Moisture On American Burying Beetles, W. Wyatt Hoback

Nebraska Department of Transportation: Research Reports

Silphid beetles in the genus Nicrophorus bury themselves during periods of inactivity, however, the influence of soil characteristics on burial behavior remains unclear. We examined soil preferences of the federally endangered Nicrophorus americanus, as well as of N. carolinus, N. marginatus, N. obscurus, and N. orbicollis, in a series of experiments. Differences in burial depth by sex were found for N. carolinus, N. marginatus, and N. obscurus, which are diurnal species. Both sexes of N. americanus bury to a mean depth of 18 cm. Soil preferences tested included sand versus sandy loam versus sandy loess, degrees of soil moisture, and …

Measuring Access To Employment To Guide And Evaluate Public Transit Service Planning In New Orleans, Kevin Harrison

University of New Orleans Theses and Dissertations

New software and technology is making it easier than ever before for public transportation planners to evaluate how quickly residents can reach jobs and other destinations. Because in the past it was difficult to measure access to opportunities, these concepts remained primarily in the theoretical and academic realms of research. This thesis reviews methods that could be used to evaluate routine bus service improvements and performs a comparative analysis of different methods in the context of New Orleans. There are many different variables in how the analysis could be performed, but this thesis focuses on the role that time of …

Spatial Distribution Of Antibiotic Resistance In Soils Receiving Beef Feedlot Runoff, Scott Speicher

Department of Environmental Engineering: Theses and Student Research

A study was conducted to provide new insight on the potential contribution to antibiotic resistance from the land application of beef feedlot runoff to soil. This study reports the distribution and quantity of antibiotic resistant bacteria (ARBs), fecal indicator bacteria (FIB), and antibiotic resistance genes (ARGs) in soil from (i) a field receiving long-term application of beef feedlot runoff holding pond effluent and (ii) a cool-season pasture with no history of supplemental manure application.

Soil samples were collected June 2015 at the U.S. Meat Animal Research Center near Clay Center, Nebraska. A response surface sampling design (RSSD) model based on …

Models For Decanting Gaseous Fuel Tanks: Simulations With Gfssp Thermal Model, Kailash Kumar Jain Munoth

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

Transport of fuel from distillation/storage plant to different parts of the world has always been challenging task for Engineers. Different methods have been proposed over the time for transporting fuel efficiently and at low cost which include Marine vessels, Pipelines, Rail Cars and Trucks. In order to transport useful amount of fuel in a reasonably sized tank, we have to liquefy it. While few fuels are easy to liquefy there are great number of fuels which liquefy only under extreme pressure/temperature conditions. Methane has a boiling point of -161.7°C at atmospheric pressure which means it has to be cooled to …

Microstructure And Properties Of Spark Plasma Sintered Moalb Ceramics, Ting Lou

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

Molybdenum aluminum boride (MoAlB) is a ternary transition metal boride which has promising aeronautic and nuclear applications. It inheres excellent properties of the binary transitional metal borides (e.g., MoB, ZrB₂) such as high melting temperature, high hardness, and thermal conductivity. Besides, MoAlB is superior to MoB because: (1) the Al element provides an oxidation resistance at high temperatures; (2) its nanolaminated structure consisting of M-B layers with alternating Al layers results in a unique damage tolerance property. In this research, polycrystalline MoAlB have been successfully synthesized and simultaneously sintered using spark plasma sintering (SPS) from molybdenum boride (MoB) …

Design And Evaluation Of Pediatric Gait Rehabilitation Robots, Cale J. Stolle

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

Gait therapy methodologies were studied and analyzed for their potential for pediatric patients. Using data from heel, metatarsal, and toe trajectories, a nominal gait trajectory was determined using Fourier transforms for each foot point. These average trajectories were used as a basis of evaluating each gait therapy mechanism. An existing gait therapy device (called ICARE) previously designed by researchers, including engineers at the University of Nebraska-Lincoln, was redesigned to accommodate pediatric patients. Unlike many existing designs, the pediatric ICARE did not over- or under-constrain the patient’s leg, allowing for repeated, comfortable, easily-adjusted gait motions. This design was assessed under clinical …

Testing The Independence Hypothesis Of Accepted Mutations For Pairs Of Adjacent Amino Acids In Protein Sequences, Jyotsna Ramanan

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

Evolutionary studies usually assume that the genetic mutations are independent of each other. However, that does not imply that the observed mutations are independent of each other because it is possible that when a nucleotide is mutated, then it may be biologically beneficial if an adjacent nucleotide mutates too.

With a number of decoded genes currently available in various genome libraries and online databases, it is now possible to have a large-scale computer-based study to test whether the independence assumption holds for pairs of adjacent amino acids. Hence the independence question also arises for pairs of adjacent amino acids within …

Towards Building A Review Recommendation System That Trains Novices By Leveraging The Actions Of Experts, Shilpa Khanal

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

Online reviews increase consumer visits, increase the time spent on the website, and create a sense of community among the frequent shoppers. Because of the importance of online reviews, online retailers such as Amazon.com and eOpinions provide detailed guidelines for writing reviews. However, though these guidelines provide instructions on how to write reviews, reviewers are not provided instructions for writing product-specific reviews. As a result, poorly-written reviews are abound and a customer may need to scroll through a large number of reviews, which could be up to 6000 pixels down from the top of the page, in order to find …

A New System For Human Microrna Functional Evaluation And Network, Jiachun Han

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

MicroRNAs are functionally important endogenous non-coding RNAs that silence host genes in animal and plant via destabilizing the mRNAs or preventing the translation. Given the far-reaching implication of microRNA regulation in human health, novel bioinformatics tools are desired to facilitate the mechanistic understanding of microRNA mediated gene regulation, their roles in biological processes, and the functional relevance among microRNAs. However, most state-of-the-art computational methods still focus on the functional study of microRNA targets and there is no e ective strategy to infer the functional similarity among microRNAs. In this study, we developed a new method to quantitatively measure the functional …

Autonomous Uavs For Near Earth Environmental Sensing, David J. Anthony

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

Unmanned aerial vehicles (UAVs) are playing an increasing role in large scale environmental monitoring. Small UAVs are increasingly used to monitor agricultural fields, infrastructure projects, and disaster areas. The combination of their sensors, ease of use, and portability make them an ideal tool for collecting information on demand about geographic regions. These small UAVs do have several significant limitations. The UAVs have very limited autonomy and fly pre-determined flight paths far above the underlying terrain, limiting the spatial resolution of the collected data. Current battery technology severely limits their flight times, which in turn limits the temporal resolution of the …

Optimization Of Irrigation Decision In Cornsoywater, Dharmic Payyala

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

A crop simulation model is used to estimate crop production as a function of weather conditions, soil parameters, and plant related inputs. These crop simulation models are extensively used by farmers, corporations and policy makers for agronomical planning and decision making. CornSoyWater is one such application which provides irrigation recommendation for soy and corn farmers using hybrid maize and soy sim models. As this is a simulation technology, the accuracy of results depends on the quality of data provided to it. One such important input parameter is weather data. CornSoyWater simulates field and crop conditions by retrieving the updated weather …

Rectilinear Steiner Tree Construction, Zhiliu Zhang

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

The Minimum Rectilinear Steiner Tree (MRST) problem is to find the minimal spanning tree of a set of points (also called terminals) in the plane that interconnects all the terminals and some extra points (called Steiner points) introduced by intermediate junctions, and in which edge lengths are measured in the L1 (Manhattan) metric. This is one of the oldest optimization problems in mathematics that has been extensively studied and has been proven to be NP-complete, thus efficient approximation heuristics are more applicable than exact algorithms.

In this thesis, we present a new heuristic to construct rectilinear Steiner trees (RSTs) with …

Finding Dna Motifs: A Probabilistic Suffix Tree Approach, Abhishek Majumdar

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

We address the problem of de novo motif identification. That is, given a set of DNA sequences we try to identify motifs in the dataset without having any prior knowledge about existence of any motifs in the dataset. We propose a method based on Probabilistic Suffix Trees (PSTs) to identify fixed-length motifs from a given set of DNA sequences. Our experiments reveal that our approach successfully discovers true motifs. We compared our method with the popular MEME algorithm, and observed that it detects a larger number of correct and statistically significant motifs than MEME. Our method is highly efficient as …

Characterization Of Molecular Communication Based On Cell Metabolism Through Mutual Information And Flux Balance Analysis, Zahmeeth Sayed Sakkaff

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

Synthetic biology is providing novel tools to engineer cells and access the basis of their molecular information processing, including their communication channels based on chemical reactions and molecule exchange. Molecular communication is a discipline in communication engineering that studies these types of communications and ways to exploit them for novel purposes, such as the development of ubiquitous and heterogeneous communication networks to interconnect biological cells with nano and biotechnology-enabled devices, i.e., the Internet of Bio-Nano Things. One major problem in realizing these goals stands in the development of reliable techniques to control the engineered cells and their behavior from the …

On Path Consistency For Binary Constraint Satisfaction Problems, Christopher G. Reeson

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

Constraint satisfaction problems (CSPs) provide a flexible and powerful framework for modeling and solving many decision problems of practical importance. Consistency properties and the algorithms for enforcing them on a problem instance are at the heart of Constraint Processing and best distinguish this area from other areas concerned with the same combinatorial problems. In this thesis, we study path consistency (PC) and investigate several algorithms for enforcing it on binary finite CSPs. We also study algorithms for enforcing consistency properties that are related to PC but are stronger or weaker than PC.

We identify and correct errors in the literature …

Power Management In Heterogeneous Mapreduce Cluster, Rojee Sunuwar

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

The growing expenses of power in data centers as compared to the operation costs has been a concern for the past several decades. It has been predicted that without an intervention, the energy cost will soon outgrow the infrastructure and operation cost. Therefore, it is of great importance to make data center clusters more energy efficient which is critical for avoiding system overheating and failures. In addition, energy inefficiency causes not only the loss of capital but also environmental pollution. Various Power Management(PM) strategies have been developed over the years to make system more energy efficient and to counteract the …

Design And Implementation Of Reconfigurable Patch Antennas For Wireless Communications, Fei He

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

Reconfigurable patch antennas have drawn a lot of research interest for future wireless communication systems due to their ability to adapt to changes of environmental conditions or system requirements. The features of reconfigurable patch antennas, such as enhanced bandwidths, operating frequencies, polarizations, radiation patterns, etc., enables accommodation of multiple wireless services.

The major objective of this study was to design, fabricate and test two kinds of novel reconfigurable antennas: a dual-frequency antenna array with multiple pattern reconfigurabilities, and a pattern and frequency reconfigurable Yagi-Uda patch antenna. Comprehensive parametric studies were carried out to determine how to design these proposed patch …

Design Of A Flexible Control Platform And Miniature In Vivo Robots For Laparo-Endoscopic Single-Site Surgeries, Lou P. Cubrich

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

Minimally-invasive laparoscopic procedures have proven efficacy for a wide range of surgical procedures as well as benefits such as reducing scarring, infection, recovery time, and post-operative pain. While the procedures have many advantages, there are significant shortcomings such as limited instrument motion and reduced dexterity. In recent years, robotic surgical technology has overcome some of these limitations and has become an effective tool for many types of surgeries. These robotic platforms typically have an increased workspace, greater dexterity, improved ergonomics, and finer control than traditional laparoscopic methods. This thesis presents the designs of both a four degree-of-freedom (DOF) and 5-DOF …

Dynamic Responses Of Wheel-Rail Systems With Block Dampers, Tzuyu Tseng

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

The wheel-rail interaction problem has been widely studied in the past few decades. In this problem, dynamic responses at the contact areas remain the central issue since they induce damage to the rail over time. In particular, the dynamic responses at the contact areas between the wheels and rails present difficulties in understanding and mathematical modeling. Even with the computer power one has today, its mathematical modeling employs the versatile numerical analysis method, the finite element method (FEM) remains a formidable challenge due to its extremely small contact areas and in turn the extremely high stress levels. In addition, friction …

Optimal Grading For Strength And Functionality Of Parts Made Of Interpenetrating Polymer Networks: Load Capacity Enhancement, Zhong Chen

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

Uniform parts with stress concentrations or singularities are prone to failure under relatively small loads, which motivates researchers to seek methods to enhance the strength of these parts. This dissertation studies the optimization of material grading to design parts made of functionally graded interpenetrating polymer networks (FG-IPNs) to improve their load capacity.

An acrylate/epoxy IPN with variations of elastic Young’s modulus, Poisson’s ratio, and ultimate stress at failure is used for optimization of a plate with stress concentration. The grading is optimized by attaching the finite element method (FEM) solver to a general purpose bound-constrained optimizer. Two examples, a plate …

Orienteering Problem: A Survey Of Recent Variants, Solution Approaches And Applications, Aldy Gunawan, Hoong Chuin Lau, Pieter Vansteenwegen

Research Collection School Of Computing and Information Systems

The Orienteering Problem (OP) has received a lot of attention in the past few decades. The OP is a routing problem in which the goal is to determine a subset of nodes to visit, and in which order, so that the total collected score is maximized and a given time budget is not exceeded. A number of typical variants has been studied, such as the Team OP, the (Team) OP with Time Windows and the Time Dependent OP. Recently, a number of new variants of the OP was introduced, such as the Stochastic OP, the Generalized OP, the Arc OP, …

Sustainable Temporary Housing: Global Trends And Outlook, Daniel V. Perrucci, Bianca A. Vazquez, Can B. Aktas

Civil Engineering Faculty Publications

The concept of sustainable housing can take many forms or definitions. The view embraced in this study for sustainable housing was a structure that is low-cost, energy efficient, and one that uses local renewable or recycled materials, while at the same time being safe and providing shelter to its occupants from the elements. Rather than focus on a few aspects of housing in isolation from spatial necessities or occupant demographics, the approach used in this study was to seek best practices for sustainable temporary housing that also accounts for local climatic conditions. The global need for temporary housing may be …

Eveleth, Minnesota: A Portrait Of My Home Town, Judith I. Luna

Graduate Theses and Dissertations

This 30-minute documentary film provides snapshots of the small northeastern iron mining town of Eveleth, Minnesota, on the Mesabi Iron Range. It uses a two-pronged approach: 1) a first-person return to the town by the filmmaker almost 50 years after graduating from high school to see how the town may have changed, 2) a look at some historical and cultural factors which made the town what it was when the filmmaker was growing up and what continues to animate the town in the face of iron mining’s decline and rebirth. The latter include the immigrant experience and influence as the …

Exploring The Production Of Extracellular Matrix By Astrocytes In Response To Mimetic Traumatic Brain Injury, Addison Walker

Graduate Theses and Dissertations

Following injury to the central nervous system, extracellular modulations are apparent at

the site of injury, often resulting in a glial scar. Astrocytes are mechanosensitive cells, which can create a neuroinhibitory extracellular environment in response to injury. The aim for this research was to gain a fundamental understanding of the affects a diffuse traumatic brain injury has on the astrocyte extracellular environment after injury. To accomplish this, a bioreactor culturing astrocytes in 3D constructs delivered 150G decelerations with 20% biaxial strain to mimic a traumatic brain injury. Experiments were designed to compare the potential effects of media type, number of …

Coarse-Grained Simulations Of The Self-Assembly Of Dna-Linked Gold Nanoparticle Building Blocks, Charles Wrightsman Armistead

Graduate Theses and Dissertations

The self-assembly of nanoparticles (NPs) of varying shape, size, and composition for the purpose of constructing useful nanoassemblies with tailored properties remains challenging. Although progress has been made to design anisotropic building blocks that exhibit the required control for the precise placement of various NPs within a defined arrangement, there still exists obstacles in the technology to maximize the programmability in the self-assembly of NP building blocks. Currently, the self-assembly of nanostructures involves much experimental trial and error. Computational modeling is a possible approach that could be utilized to facilitate the purposeful design of the self-assembly of NP building blocks …

Examination Of Pseudomonas Fluorescence As A Recombinant Expression Host: Cloning, Expression, And Chromatography, Ahmed K.Ali Elmasheiti

Graduate Theses and Dissertations

In an effort to expand the pool of bacterium useful for biotechnology applications, Pseudomonas fluorescens, a common gram negative microbe, was examined for its ability to function in a recombinant setting. P. fluorescens is ubiquitous in nature and was initially identified as a soil bacterium found in dirt and is typically associated with plant material. Past literature indicates that it shared characteristics common to Escherichia coli and Bacillus subtilis, including simple growth conditions and potential cloning vectors, providing motivation to look into both the upstream and downstream characteristics of this bacterium. First, it was demonstrated that P. fluorescens could be …

Just In Time Assembly (Jita) - A Run Time Interpretation Approach For Achieving Productivity Of Creating Custom Accelerators In Fpgas, Sen Ma

Graduate Theses and Dissertations

The reconfigurable computing community has yet to be successful in allowing programmers to access FPGAs through traditional software development flows. Existing barriers that prevent programmers from using FPGAs include: 1) knowledge of hardware programming models, 2) the need to work within the vendor specific CAD tools and hardware synthesis. This thesis presents a series of published papers that explore different aspects of a new approach being developed to remove the barriers and enable programmers to compile accelerators on next generation reconfigurable manycore architectures. The approach is entitled Just In Time Assembly (JITA) of hardware accelerators. The approach has been defined …