Digital Commons Network^™

An Investigative Study Of The Snapthrough, Snapback And The Stiffness Properties Of A Kirigami Unit Cell, Aditya Girish Lele

All Theses

Until recently, Carbon Fiber was considered to be a space-age material because of its applications. However, due to the advancements in the synthesis of these materials and manufacturing carbon fiber on a large scale, it has now become possible to use carbon fiber in day-to-day applications. Components which were traditionally being made out of steel or aluminum are now being redesigned and made using carbon fiber composites. The Boeing 787 Dreamliner fuselage is an excellent example where carbon fiber has been used as the major component. This is due to the fact that carbon fiber components are much lighter and …

An Experimental Investigation Of Combined Symmetric Asymmetric Composite Laminates, Guy Maximilian Kemmann

All Theses

It has been found that certain asymmetric composite laminates exhibit bistability, and are thus called bistable composite laminates. A bistable composite laminate is a composite laminate that exhibits multiple stable static equilibrium states. If the bistable composite is actuated it will snap to its secondary equilibrium state and then remain there without any further actuation. This unique behavior of bistable composites has made them the subject of much research in the areas of morphing structures as well as energy harvesting. Much of the research done on bistable laminates has been focused on the fundamental characterization of the bistable behavior and …

Using Contraflow On A Road Segment To Improve Emergency Response Vehicle Speed In A Connected Vehicle Environment, Nitin Srinath

All Theses

Emergency response vehicles (ERVs) need to reach their destinations as fast as possible. Road congestion and unpredictable movement of non-emergency vehicles (non-ERVs) makes it challenging for the ERV to move quickly. By using the autonomous/connected vehicle environment, instructions can be disseminated to the non-ERVs in the vicinity of the ERV to facilitate its passage within a link. In this thesis, an extension to a previously developed mathematical program is proposed to enable the ERV to use a contraflow lane when considerable speed gains can be potentially achieved. An experimental analysis is conducted to evaluate the sensitivity of the model’s output …

Thermal Mechanical Numerical Modeling Of Friction Element Welding, Ankit Varma

All Theses

With the objective of minimizing carbon footprint of vehicles, different organizations across the world are increasingly enforcing higher fuel efficiency targets for the automobile manufacturers. To improve the fuel economy while retaining or further improving the structural integrity, the automobile industry is vigorously shifting towards substituting conventional heavy materials like cast iron with new age materials such as aluminum alloys, steel alloys, etc. which are not only much lighter but also offer superior strength-to-weight ratio. Engineers use a mix of these new age materials with the aim of maximizing the benefits from each material. However, the utilization of such materials …

Developing Optimization System For Improving Highway Network Performance Under Seismic Hazards: A Case Study Of Charleston, Sc, Nixon Wonoto

All Theses

A significant number of bridges in the Central and Southeastern United States (CSUS) are known to have a design that is lacking or no seismic consideration. In an article by Wong et al., Charleston is considered an active seismic zone, and the economic loss from the Charleston region could reach over $14 billion if 1886 Charleston’s earthquake would happen again in the near future. Due to lack of present consideration in seismic design for bridges in CSUS, there has been emerging research that studies retrofit strategies for CSUS region such as in Charleston. However, most of the retrofit program, including …

Implementation And Applications Of Art-Directable Ocean Simulation Tools, Jingcong Zhang

All Theses

Ocean effects are important aspects of the filmmaking. They help to establish emotions and dynamism via the behaviors of the oceans, and provides the different atmosphere for storytelling by creating various ocean scenarios. Gilligan is a prototype environmental scene simulator, whose core technique of the ocean simulation has been widely used in feature film productions. This thesis develops ocean simulation tools working with Maya and Houdini with the techniques provided by Gilligan. The Gilligan-Maya workflow executes ocean simulation methods in Gilligan to simulate oceans. The Gilligan-Houdini workflow integrates Gilligan into Houdini, containing a Houdini wrapper of Gilligan, along with a …

Finite Element Discretizations For Linear Elasticity, Emma Cinatl

All Theses

The elasticity equations describe how an elastic material moves under a force. An elastic material is one that returns to its original shape after the force is lifted. Modeling elasticity is useful in manufacturing applications such as suspension cables and nail bending, and biological applications such as weight on bones and tendons [1]. In this thesis we study the modeling of nearly incompressible linearly elastic materials. A nearly incompressible material is one that does not change much under pressure. Linearly elastic materials exhibit small deformations under a force. Standard finite element methods do not work well on nearly incompressible materials …

Examining The Role Of Summer Camps In Developing Academic And Workplace Readiness, Cait Wilson, Jim Sibthorp

Journal of Youth Development

Summer camps are an effective setting for youth to develop skills essential for academics and the workplace yet are often not recognized as such. Therefore, the primary aim of this study was to investigate learning outcomes from camp most applicable to academics and workplace readiness. As a secondary aim, the researchers sought to identify the mechanisms at camp that support this learning. Youths’ primary learning outcomes include relationship skills, teamwork, how to live with peers, self-confidence, organization, responsibility, independence, perseverance, career orientation, and emotion regulation. In general, mechanisms that supported participants’ learning of outcomes included experiential learning, camp as separate …

The Role Of Camp In Shaping College Readiness And Building A Pathway To The Future For Camp Alumni, Anja Whittington, Barry Garst

Journal of Youth Development

The purpose of this study was to examine whether attending camp promotes college readiness skills in camp alumni. A sample of 420 participants retrospectively reflected on their camp experience and how it helped them gain college readiness skills through an online survey. Quantitative results suggested that a variety of college readiness skills are impacted by the camp and differ slightly based on male and female respondents. Qualitative analysis indicated that camp influences academic pursuits by inspiring one’s academic interest, shaping where one studies, and motivating one to persevere and complete college. Supportive peers and adults within the camp setting influence …

Intermittent Estimation Of Volumetric Mass Transfer Coefficient Using Offgas Sensor Data For Continuous Our Estimation For Cho Cell Culture, Swadeel Deepak Gaad

All Theses

For the last several years drugs based on monoclonal antibodies have been manufactured using Chinese Hamster Ovaries (CHO) cells by the bio-pharmaceutical industries to treat cancer and other autoimmune diseases. Several control strategies are used to increase the productivity and efficiency in bio-pharmaceutical manufacturing. Cell growth can be controlled by adjusting the feed rate based on oxygen uptake rate of the cells in the bioreactor. Determining the volumetric mass transfer coefficient and oxygen saturation concentration is vital in correctly estimating oxygen uptake rate. Thus, a robust and efficient method to determine volumetric mass transfer coefficient and oxygen saturation concentration, which …

An Investigation Into The Usability Of An Innovation Management Assessment Tool, Elizabeth Jane Westerlund Gendreau

All Theses

Two tools for assessing external knowledge absorption maturity were developed during Part 1 of this research based upon the work of a previous researcher. The first of these tools assesses the maturity of a single organization, or actor. The second tool assesses the maturity of the collaborative innovation network that actor is a part of. Each tool produces a maturity profile for that actor or network which can then be used to inform innovation strategy decision making. An actor maturity assessment tool had been developed in previous research, however it did not consider how important evaluation criteria were to the …

An Introduction To Homological Algebra And Its Applications, Todd Anthony Morra

All Theses

Ext modules have a number of applications in homological algebra and commutative abstract algebra as a whole. In this document we prove Ext modules are well-defined and motivate their study by characterizing the depth of a ring in terms of Ext modules as well as by giving an application in combinatorial commutative algebra. In particular, we give a way of constructing Cohen-Macaulay rings from simple graphs and show that when we localize these rings, their type is easily computed by counting the number of maximal cliques in the appropriate simple graph. When R is a noetherian ring and S the …

Numerical Analysis Of Scramjet Cavity Flameholders At Varying Flight Mach Numbers, Matthew Quinones

All Theses

Various types of air breathing engines are used as propulsion devices in aviation. At high flight velocities, the use of a ramjet or supersonic combustion ramjet (scramjet) may be preferred due to the natural compressibility of air at high speed. A scramjet, while similar to the ramjet, does not slow air to subsonic speeds prior to combustion, allowing it to operate at much higher flight velocities at very high altitude. For this reason, however, the residence time of air inside of the combustor is on the order of milliseconds, requiring rapid mixing and ignition of the fuel to generate adequate …

Physical And Virtual Prototyping In Product Design, Matthew S. Sheppard

All Theses

The objective of this research is to demonstrate the role of physical and virtual prototyping in product design. The product development process that was used as a case study for this research was a piece of equipment that improves the ability to capture accurate dimensions of extruder bores of diameter ranging from 39.69 mm to 92.08 mm and depth ranging from 96.52 cm to 327.66 cm. The motivation is that the Eastman Chemical Company expressed difficulty capturing accurate measurements of circularity, diameter, and runout throughout the depth of their polymer extruders because conventional technology is cumbersome at significant depths and …

The Effects Of Using An Information Literacy Model On The Information Seeking Behavior Of Sixth-Grade Students, Jessica L. Kohout-Tailor

All Dissertations

This action research study describes how teaching an information literacy model affects the information behavior of sixth-grade students. The theoretical framework that supported this study was Carol Kuhlthau’s Information Search Process or ISP (1989). This study used a sequential mixed-methods design to examine the following questions: “How will teaching the Simple Four information literacy model (Alewine, 2006) to sixth-grade students affect their information seeking behavior?” The study also explored the effects the model had on students’ affective behavior through the second research question: “How will teaching the Simple Four information literacy model (Alewine, 2006) to sixth-grade students affect their confidence …

The Emac Scheme For Navier-Stokes Simulations, And Application To Flow Past Bluff Bodies, Sergey Charnyi

All Dissertations

The Navier-Stokes equations model the evolution of water, oil, and air flow (air under 220 m.p.h.), and therefore the ability to solve them is important in a wide array of engineering design problems. However, analytic solution of these equations is generally not possible, except for a few trivial cases, and therefore numerical methods must be employed to obtain solutions. In the present dissertation we address several important issues in the area of computational fluid dynamics. The first issue is that in typical discretizations of the Navier-Stokes equations such as the mixed finite element method, the conservation of mass is enforced …

Tight Representations Of Specially-Structured 0-1 Linear, Quadratic, And Polynomial Programs, Audrey N. Devries

All Dissertations

This research derives improved mathematical representations for various expressions of binary variables. There are three main efforts, consisting of: the Target Visitation Problem (TVP), the Quadratic Linear Ordering Problem (QLOP), and a special family of monomials of binary variables. For the first two efforts, which are known in the literature to be (mixed) 0-1 programs, we derive new families of valid inequalities that tighten existing forms and lead to superior performance. We give computational experience to show the advantages of our approaches. For the third effort, we provide an explicit convex hull representation for special forms of monomials of binary …

Computational Approaches To Understanding Structure-Function Relationships At The Intersection Of Cellular Organization, Mechanics, And Electrophysiology, Tyler George Harvey

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The heart is a complex mechanical and electrical environment and small changes at the cellular and subcellular scale can have profound impacts at the tissue, organ, and organ system levels. The goal of this research is to better understand structure-function relationships at these cellular and subcellular levels of the cardiac environment. This improved understanding may prove increasingly important as medicine begins shifting toward engineered replacement tissues and organs. Specifically, we work towards this goal by presenting a framework to automatically create finite element models of cells based on optical images. This framework can be customized to model the effects of …

Augmenting A Hazard Analysis Method With Error Propagation Information For Safety-Critical Systems, Fryad Khalid M. Rashid

All Dissertations

Safety-critical systems need specific activities in the software development life cycle to ensure that the system will operate safely. The objective of this dissertation is to develop a new safety analysis method to identify hazards. The method uses error propagation information and the internal structure rather than the interfaces of a system. We propose development procedures to augment STPA (System-Theoretic Process Analysis) with error propagation information derived from the architecture description of a system represented in the AADL (Architecture Analysis Design Language). We will focus on how the AADL error ontology can be used to assist in identifying errors, how …

The Effects Of Various Retort Motions On The Rate Of Heat Penetration Of A Food Simulant In Pouches, Mollye Macnaughton

All Dissertations

Processing foods in a retort is a reliable and established method of creating sterile and shelf stable products. The formula of the product and the package size dictates the processing time. Rotary retorts were invented to agitate cans to reduce the processing times and create uniform heating within the can. Recently, horizontal reciprocating agitation has become a feature of retorts referred to as Gentle Motion® and Shaka®. Oscillating agitation is an even newer possible retort motion. This research experiment was designed to (1) determine the effects of oscillating continuously and oscillating-dwell time on the rate of heat penetration in a …

Towards Automated Verification Of Object-Based Software With Reference Behavior, Yu-Shan Sun

All Dissertations

Automated verification is critical for ensuring that an implementation is correct and meets the specified behavior on every valid input. Verification should be modular to promote reuse and to scale up. However, for code that involves explicit reference behavior, there is the added complexity of reasoning that only the intended objects are being affected. This research focuses on simplifying automated verification and enabling modular verification using data abstractions that hide explicit reference behavior. While avoiding explicit reference behavior simplifies reasoning for a majority of software components, for capturing unavoidable reference behavior, such as that needed to implement classes of lower-level …

Surface Functionalized Gold Nanoparticle Applications In Catalysis And Lipid-Nanoparticle Assemblies, Saptarshi Chakraborty

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The general objectives of my dissertation are to devise strategies to impart unique functionality to gold nanoparticles (AuNPs) through surface modification and utilizing such surface-functionalized AuNP systems to 1) facilitate colloidal catalyst recovery and reuse while maintaining activity and 2) measure the interactions of engineered AuNPs with biological membranes as related to stimuli-responsive liposomal therapeutics.

AuNP surface functionalization is an essential step in the synthesis, stability and functionality-specific applications of AuNPs. Due to the ability to control AuNP shape, size and surface properties, AuNP applications have seen an exponential growth in various sectors that include catalysis, biomedicine, drug-delivery, sensing, imaging, …

Improving Deep Reinforcement Learning Using Graph Convolution And Visual Domain Transfer, Sufeng Niu

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Recent developments in Deep Reinforcement Learning (DRL) have shown tremendous progress in robotics control, Atari games, board games such as Go, etc. However, model free DRL still has limited use cases due to its poor sampling efficiency and generalization on a variety of tasks. In this thesis, two particular drawbacks of DRL are investigated: 1) the poor generalization abilities of model free DRL. More specifically, how to generalize an agent's policy to unseen environments and generalize to task performance on different data representations (e.g. image based or graph based) 2) The reality gap issue in DRL. That is, how to …

Discrete Element Modeling Of The Grading- And Shape-Dependent Behavior Of Granular Materials, Zhengshou Lai

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Granular materials, such as sand, biomass particles, and pharmaceutical pills, are widespread in nature, industrial systems, and our daily life. Fundamentally, the bulk mechanical behavior of such materials is governed by the physical and morphological features of and the interactions among constituent particles at the microscopic scale. From a modeling standpoint, the particle-based discrete element method (DEM) has emerged as the most prevalent numerical tool to model and study the behavior of granular materials and the systems they form. A critical step towards an accurate and predictive DEM model is to incorporate those physical and morphological features (e.g., particle size, …

Trust-Based Control Of Robotic Manipulators In Collaborative Assembly In Manufacturing, Behzad Sadrfaridpour

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Human-robot interaction (HRI) is vastly addressed in the field of automation and manufacturing. Most of the HRI literature in manufacturing explored physical human-robot interaction (pHRI) and invested in finding means for ensuring safety and optimized effort sharing amongst a team of humans and robots. The recent emergence of safe, lightweight, and human-friendly robots has opened a new realm for human-robot collaboration (HRC) in collaborative manufacturing. For such robots with the new HRI functionalities to interact closely and effectively with a human coworker, new human-centered controllers that integrate both physical and social interaction are demanded. Social human-robot interaction (sHRI) has been …

Matching Potential In Randomized Complete Block Designs, Elaine Sotherden

All Dissertations

A small sheep experiment (nobs=32) planned to use a randomized complete block design (RCBD) treatment assignment of two binary factors. Complications creating the RCBD blocks prompted the researchers to discard the original blocks from the initial analysis plan and to rearrange their experimental units into new groups using linear covariate adjustment. We compare the blocks from the experiment's initial analysis plan and the groups from the researcher's linear covariate adjustment to groups formed by potential matching methods. We evaluate these three analysis approaches on the original sheep dataset and on simulated sheep datasets. We find that the groups created using …

A Numerical Method For The Navier Stokes Equations In A Velocity-Vorticity Form, Liang Zhao

All Dissertations

In physics, the Navier-Stokes equations (NSE) describe Newtonian fluid flows. Instead of focusing on the standard NSE with velocity and pressure as primary variables, we are interested in the Navier Stokes equations in a velocity-vorticity form (NSE-VV). In NSE-VV, vorticity is included in the system as an independent variable so that it can be computed directly. The main contribution of this thesis is proposing a numerical method for solving NSE-VV, which includes an efficient solver, an adaptive mesh refinement strategy and error analysis. A nested solver plays a fundamental role in the numerical method of NSE-VV. Similar to how it …

Characterization And Cultivation Of Marine Protist, Thraustochytrium Striatum For High-Value Bioproducts, Rui Xiao

All Dissertations

DHA/EPA producing marine protists have recently become more attractive due to their additional high-value products, including extracellular enzymes, extracellular polymeric substances (EPS), and astaxanthin. In this study, Thraustochytrium striatum ATCC 24473 was studied and the cultivation conditions were been optimized to achieve high biomass and fatty acid yield. Results showed that seawater salinity, neutral pH and mild rotation speed favored biomass growth, while better lipid accumulation was observed under high C/N ratio, higher salinity or high pH. Comparison in different carbon sources showed starch and glycerol improved fatty acid accumulation the most, and ammonia chloride was the best nitrogen source …

Edge-Computing Deep Learning-Based Computer Vision Systems, Edwin Lee Weill

All Dissertations

Computer vision has become ubiquitous in today's society, with applications ranging from medical imaging to visual diagnostics to aerial monitoring to self-driving vehicles and many more. Common to many of these applications are visual perception systems which consist of classification, localization, detection, and segmentation components, just to name a few. Recently, the development of deep neural networks (DNN) have led to great advancements in pushing state-of-the-art performance in each of these areas. Unlike traditional computer vision algorithms, DNNs have the ability to generalize features previously hand-crafted by engineers specific to the application; this assumption models the human visual system's ability …

Cases Of Contingent Stem Faculty Who Practice Critical Pedagogies With/In The Neoliberal University, Jeffrey Michael Kenney

All Dissertations

An increasingly neoliberal university means diminishing resources and labor security for those located in the lowest echelon, particularly those engaged in critical/radical/activist projects. The purpose of this study was to generate knowledge in an effort to sustain and advance critical pedagogical practices in college teaching. This study focused principally on the knowledge and insights of contingent STEM faculty who practice critical pedagogies in the neoliberal conditions of public universities. Utilizing critical and pragmatic perspectives, I explored both the ingenuity and practicality of the participants’ praxis as well as examined the structural machinations of neoliberal capitalism within their teaching and learning …