Engineering Commons^™

Synthesis Of Titania Thin Films With Controlled Mesopore Orientation: Nanostructure For Energy Conversion And Storage, Suraj R. Nagpure

Theses and Dissertations--Chemical and Materials Engineering

This dissertation addresses the synthesis mechanism of mesoporous titania thin films with 2D Hexagonal Close Packed (HCP) cylindrical nanopores by an evaporation-induced self-assembly (EISA) method with Pluronic surfactants P123 and F127 as structure directing agents, and their applications in photovoltaics and lithium ion batteries. To provide orthogonal alignment of the pores, surface modification of substrates with crosslinked surfactant has been used to provide a chemically neutral surface. GISAXS studies show not only that aging at 4°C facilitates ordered mesostructure development, but also that aging at this temperature helps to provide orthogonal orientation of the cylindrical micelles which assemble into an …

Three-Dimensional Microstructure-Based Models For Fatigue Crack Nucleation And Fatigue Crack Branching In High Strength Al Alloys, Lin Yang

Theses and Dissertations--Chemical and Materials Engineering

This study is concerned with using numerical three-dimensional microstructure-based models to quantify the multi-site fatigue crack initiation behaviors by simulating the effects of pores in a cast aluminum alloy, and to analyze the mechanism of fatigue crack branching in thick aluminum alloy plates. It has been recently recognized the three-dimensional effects of pores on fatigue crack initiation, which provide opportunity to quantitatively identify the fatigue weak-link density and strength distribution in aluminum alloy. The stress and strain fields around a micro-pore in an A713 aluminum alloy (an elasto-plastic media) under cyclic loading were quantified as a function of pore position …

Lnvestigation Of The Critical Role Of Polymeric Binders For Silicon Negative Electrodes In Lithium-Lon Batteries, Jiagang Xu

Theses and Dissertations--Chemical and Materials Engineering

Silicon is capable of delivering a high theoretical specific capacity of 3579 mAh g^-1, which is about 10 times higher than that of the state-of-the-art graphite-based negative electrodes for lithium-ion batteries (LIBs). However, the poor cycle life of silicon electrodes, caused by the large volumetric strain during cycling, limits the commercialization of silicon electrodes. As one of the essential components, the polymeric binder is critical to the performance and durability of lithium-ion batteries as it keeps the integrity of electrodes, maintains conductive path and must be stable in the electrolyte. The guideline for binder selection of silicon electrodes …

First-Principles Studies Of Structure-Property Relationships: Enabling Design Of Functional Materials, Qunfei Zhou

Theses and Dissertations--Chemical and Materials Engineering

First-principles calculations based on quantum mechanics have been proved to be powerful for accurately regenerating experimental results, uncovering underlying myths of experimental phenomena, and accelerating the design of innovative materials. This work has been motivated by the demand to design next-generation thermionic emitting cathodes and techniques to allow for synthesis of photo-responsive polymers on complex surfaces with controlled thickness and patterns. For Os-coated tungsten thermionic dispenser cathodes, we used first-principles methods to explore the bulk and surface properties of W-Os alloys in order to explain the previously observed experimental phenomena that thermionic emission varies significantly with W-Os alloy composition. Meanwhile, …

Csce 411h: Data Modeling For Systems Development—A Peer Review Of Teaching Project Inquiry Portfolio, Hongfeng Yu

UNL Faculty Course Portfolios

A new course CSCE411H has been developed in 2015-2016. The course tackles the learning of traditional and emerging data modeling techniques in big data related areas from the system and application perspectives. The students have mixed background in Business, Engineering, and Art and Science with different levels. These have introduced a unique set of challenges in the development of this new course. In this inquiry portfolio, I investigated if the adjustment of assignments can benefit the team work of the students with a variety of background. Through the data collection and analysis, the investigation showed that the new assignment design …

Ae 2250: Construction Graphics And Design—A Peer Review Of Teaching Project Benchmark Portfolio, Asregedew Woldesenbet

UNL Faculty Course Portfolios

This course portfolio designs and documents AE 2250 (Construction Design and Graphics) course that is taught in Spring 2016 at UNL's College of Engineering under the Durham School of Architectural Engineering and Construction program. The course is intended to introduce BIM (Building Information Modeling) to architectural engineering, construction engineering, construction management and civil engineering students ranging from freshman to juniors. This course portfolio documents the challenges associated with delivering this course, tailors the course objectives, activities and tracking measures to meet the course objectives throughout the semester. This portfolio uses quantitative and qualitative measures to track student performances and learning …

Matl 260/360: Elements Of Materials Science—A Peer Review Of Teaching Project Benchmark Portfolio, Bai Cui

UNL Faculty Course Portfolios

The goal of MATL 260/360 Elements of Materials Science is to make undergraduate students understand the fundamental concepts of the microstructure-property relationship of materials. This course portfolio addresses several key questions in teaching, such as how to teach new knowledge more effectively, how to increase student engagement, how to promote students’ interests and motivations, and how to use this course to improve students’ analysis and critical thinking skills.

To address each of key questions, the course activities include: relating the new knowledge with daily-life and industry examples; giving PPT slides for after- class study; assigning homework questions after each lecture; …

Behavioral Traps In Flight Crew-Related 14 Cfr Part 121 Airline Accidents, Jonathan Velázquez

Doctoral Dissertations and Master's Theses

This dissertation examined pilot behavioral traps in the multi-crew Part 121 air carrier environment. Behavioral traps are accident-inducing operational pitfalls aviators may encounter as a result of poor decision making. The traps studied were: Loss of Situational Awareness; Neglect of Flight Planning, Preflight Inspections and Checklists; Peer Pressure; Get-There-Itis; and Unauthorized Descent Below an Instrument Flight Rule (IFR) Altitude. The purpose of this dissertation was to study the nature of their occurrence in the airline domain. Another key component was to explore the relationships between the behavioral traps and factors such as pilot age, pilot flight experience, weather, flight conditions, …

Computer Vision Based Structural Identification Framework For Bridge Health Mornitoring, Tung Khuc

Electronic Theses and Dissertations

The objective of this dissertation is to develop a comprehensive Structural Identification (St-Id) framework with damage for bridge type structures by using cameras and computer vision technologies. The traditional St-Id frameworks rely on using conventional sensors. In this study, the collected input and output data employed in the St-Id system are acquired by series of vision-based measurements. The following novelties are proposed, developed and demonstrated in this project: a) vehicle load (input) modeling using computer vision, b) bridge response (output) using full non-contact approach using video/image processing, c) image-based structural identification using input-output measurements and new damage indicators. The input …

Low Impact Development Analysis And Comparative Assessment Of Wet Detention Ponds With Floating Treatment Wetlands, Nicholas Hartshorn

Electronic Theses and Dissertations

The aim of this thesis is to examine, develop, and assess innovative best management practices (BMPs) in stormwater management for pollutant reduction, flood control, and environmental sustainability. Previous research has clearly shown that urban stormwater runoff quickly transports pathogens, metals, sediment, and chemical pollutants to receiving waterbodies, resulting in the degradation of receiving waters and disruption of ecological networks. In response to this growing concern, regulatory agencies, such as the Environmental Protection Agency (EPA) and the Florida Department of Environmental Protection (FDEP), have set forth regulations aimed at protecting and restoring waterbodies. These regulations include numeric nutrient criteria (NNC) and …

It Centralization And The Innovation Value Chain In Higher Education: A Study For Promoting Key Innovations Through Innovation Management And Organizational Design, Edmund Udaya Clark

All Graduate Theses, Dissertations, and Other Capstone Projects

The purpose of the present study was to investigate the impact of organizational centralization in higher education technology support units on institutional innovativeness. The centralization tools used for the present study included measures developed by Hage & Aiken (1971), Kaluzny, et al. (1974), and Ferrell & Skinner (1988). The innovativeness measures were established by Hansen & Birkinshaw's (2007) tool for evaluating innovation value chain activities in organizations. Data were gathered from a nation-wide sample (n = 303) of IT workers at 38 research one institutions in the United States. The results indicated that innovation value chain activities (idea generation, conversion, …

Process Improvement By Lean Thinking In Trucking Industry, Abhiram Reddy Ramasahayam

All Graduate Theses, Dissertations, and Other Capstone Projects

Manufacturing industries with complex production systems are struggling with designing optimal process to increase throughput. Companies will require high amount of labor and process improvement resources to sustain growth and delivery quality products to its customers. A chain of value added activities when designed and deployed with help of lean based methodologies can create high efficiency process. In this paper we have studies and implemented value added process based on the lean manufacturing methodologies which was adapted on the shop floor.

In many traditional truck body production industries have facing many problems like low production rate, big lead times, material …

Global Data Association For Multiple Pedestrian Tracking, Afshin Dehghan

Electronic Theses and Dissertations

Multi-object tracking is one of the fundamental problems in computer vision. Almost all multi-object tracking systems consist of two main components; detection and data association. In the detection step, object hypotheses are generated in each frame of a sequence. Later, detections that belong to the same target are linked together to form final trajectories. The latter step is called data association. There are several challenges that render this problem difficult, such as occlusion, background clutter and pose changes. This dissertation aims to address these challenges by tackling the data association component of tracking and contributes three novel methods for solving …

Modeling Early Stage Bone Regeneration With Biomimetic Electrospun Fibrinogen Nanofibers And Adipose-Derived Mesenchymal Stem Cells, Michael P. Francis, Yas M. Moghaddam-White, Patrick C. Sachs, Matthew J. Beckman, Stephen M. Chen, Gary L. Bowlin, Lynne W. Elmore, Shawn E. Holt

School of Medical Diagnostics & Translational Sciences Publications

The key events of the earliest stages of bone regeneration have been described in vivo although not yet modeled in an in vitro environment, where mechanistic cell-matrix-growth factor interactions can be more effectively studied. Here, we explore an early-stage bone regeneration model where the ability of electrospun fibrinogen (Fg) nanofibers to regulate osteoblastogenesis between distinct mesenchymal stem cells populations is assessed. Electrospun scaffolds of Fg, polydioxanone (PDO), and a Fg:PDO blend were seeded with adipose-derived mesenchymal stem cells (ASCs) and grown for 7-21 days in osteogenic differentiation media or control growth media. Scaffolds were analyzed weekly for histologic and molecular …

Accessible Bioprinting: Adaptation Of A Low-Cost 3d-Printer For Precise Cell Placement And Stem Cell Differentiation, John A. Reid, Peter A. Mollica, Garett D. Johnson, Roy C. Ogle, Robert D. Bruno, Patrick C. Sachs

School of Medical Diagnostics & Translational Sciences Publications

The precision and repeatability offered by computer-aided design and computer-numerically controlled techniques in biofabrication processes is quickly becoming an industry standard. However, many hurdles still exist before these techniques can be used in research laboratories for cellular and molecular biology applications. Extrusion-based bioprinting systems have been characterized by high development costs, injector clogging, difficulty achieving small cell number deposits, decreased cell viability, and altered cell function post-printing. To circumvent the high-price barrier to entry of conventional bioprinters, we designed and 3D printed components for the adaptation of an inexpensive 'off-the-shelf' commercially available 3D printer. We also demonstrate via goal based …

It Governance-An Integrated Framework And Roadmap: How To Plan, Deploy And Sustain For Improved Effectiveness, Gad J. Selig

Journal of International Technology and Information Management

The issues, opportunities and challenges of effectively managing and governing an organization’s Information Technology (IT) demands, investments and resources has become a major concern of the Board and executive management in enterprises on a global basis. A rapidly growing number of organizations have become increasingly dependent on a broad array of technologies to manage and grow their businesses. IT is an integral part of most organizations today and will certainly become more critical in the future. This paper proposes a comprehensive and integrated IT governance framework and roadmap which identifies the appropriate current and emerging best practices methodologies for each …

Usability Test Of Personality Type Within A Roommate Matching Website: A Case Study, Mrinalini Shekhawat, Shilpa Deshmukh, Gabriel Monroy, Anupriya Tiwari, Xiaoyun He, Heechang Shin, Yuan Hong, Haibing Lu

Journal of International Technology and Information Management

We designed and built a roommate matching website, exclusively for students, which allow students to have a central point in which they can meet credible roommate candidates, search for verified housing, and easily reach out to these individuals to further their relationship, and eventually share living space. Our website aims to allow a user to search for compatible roommates not just by living habits, but by tying in the personality of candidates in reference to their own personality type. This type of personality matching in conjunction with a standard behavioral survey is the basis of the algorithm used for roommate …

Table Of Contents

Journal of International Technology and Information Management

Table of Contents for Volume 25 Number 4

Conceptual Models On The Effectiveness Of E-Marketing Strategies In Engaging Consumers, Cheristena Bolos, Efosa C. Idemudia, Phoebe Mai, Mahesh Rasinghani, Shelley Smith

Journal of International Technology and Information Management

Effective marketing has always been an important factor in business success. Without the ability to identify customers and convince them to purchase the product or service being offered, businesses would not survive. Recent advancements in technology have given rise to new opportunities to engage customers through the use of electronic marketing (e-marketing). E- marketing draws from traditional marketing principles, while also expanding the types of strategies available to companies. Websites, social media, and online marketplaces are just some examples of how businesses are leveraging e-marketing approaches to connect with potential customers. In formulating sound e-marketing strategies, it is important for …

Healthcare System-Use Behavior: A Systematic Review Of Its Determinants, Jiming Wu

Journal of International Technology and Information Management

To understand patient and physician behavior, researchers have investigated the determinants of using healthcare information systems. Although this stream of research has produced important findings, it has yet to appreciably advance our understanding of system-use behavior in healthcare. To fill this gap, the current paper employs a systematic review to synthesize past research, reveal the key determinants of healthcare system usage, and illuminate a deeper understanding of the topic. This study thus helps healthcare researchers expand their baseline knowledge of these core determinants and conduct more fruitful future research on system-use behavior in healthcare.

Smart Fabrics For Colorimetric Detection, Breland Edwards

UROP Posters

Due to the prevalence of chemical warfare, soldiers often carry chemical sensing devices, to warn of oncoming nerve agents. However, these devices are cumbersome. A lightweight, wearable chemical sensing fabric that doubles as a protectant against toxins would be beneficial. This fabric can be created by incorporating (1) organophosphate hydrolase, an enzyme capable of degrading organophosphates and releasing an acidic by product, and (2) polyaniline, a color changing polymer that changes from purple to green in the presence of acid, into nylon or polyvinyl alcohol nanofibers. The first step is to produce fabrics containing polyaniline and demonstrate that the fabrics …

Modeling Of Selection Of Supply Sources For Hospitals, Siva Raghava Sai Rohith Valiveti

Graduate Dissertations and Theses

Most of the hospitals in the USA carry out their purchasing of supplies, including pharmaceuticals, through Group Purchasing Organizations (GPO). GPO is an organization, which aggregates procuring volumes of their member hospitals and negotiates low prices from manufacturers or vendors. According to 2013 statistics, 98% of hospitals in U.S. are purchasing their bulk health care products through GPOs, and it saves U.S. health care industry approximately $36 billion annually. Through these hospitals enjoy advantages by purchasing through their GPOs, there are some disadvantages such as paying membership fees to their GPOs, restricting the purchasing power of the hospitals outside their …

Scalable Methods For Monitoring Limited Access Roadways Using Crowd-Sourced Probe Data, Howell Li, Stephen M. Remias, Aaron Taylor, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Real-Time Probe Data Dashboards For Interstate Performance Monitoring During Winter Weather And Incidents, Margaret Mcnamara, Howell Li, Stephen Remias, Deborah Horton, Ed Cox, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Scaling Detailed High-Resolution Data Split Performance Measures To Statewide System Level Management, Howell Li, Christopher M. Day, James R. Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Use Of High Resolution Signal Controller Data To Identify Red Light Running, Steven M. Lavrenz, Christopher M. Day, Jay Grossman, Rick Freije, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Rate Of Pedestrian Signal Phase Actuation As A Proxy Measurement Of Pedestrian Demand, Christopher M. Day, Hiromal Premachandra, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Extending Link Pivot Offset Optimization To Arterials With Single Controller Diverging Diamond Interchange, Christopher M. Day, Steven M. Lavrenz, Amanda L. Stevens, R Eric Miller, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Opportunities For Detector-Free Signal Offset Optimization With Limited Connected Vehicle Market Penetration: A Proof-Of-Concept Study, Christopher M. Day, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Eliminating Magnetic Forces From The Surface Tension Measurement Of Magnetic Surfactants, Emily Koehler

Honors Theses

Surfactants have many applications due to their ability to reduce the surface tension between two phases. Magnetic surfactants, a relatively new form of surfactants, offer the possibility of further controlling a surfactant system by using an external magnetic field to induce alignment on the molecular level. One method of studying a magnetic field's effect on the magnetic surfactant system involves analyzing the change in surface tension at varied solution concentrations both in and outside a magnetic field. The pendent drop method uses the downward gravitational force on a droplet suspended from a needle to find the surface tension based on …