Digital Commons Network^™

Real-Time, Variable-Depth Tillage For Managing Soil Compaction In Cotton Production, Jonathan Fox

All Theses

Cotton is one of the most important crops in the southern USA with an estimated production value of $6 billion. Cotton root growth is often hindered in the Southeastern U.S. due to the presence of root-restricting soil layers. Soils in this region have three distinct layers, the A horizon, the E horizon and the Bt horizon. The E horizon is often plagued with a hardpan layer that has a much higher bulk density than optimum for crop production. This limits the ability of the plant roots to penetrate into the Bt horizon for uptake of water and nutrients, therefore, reducing …

An Experimental Investigation Of The Effect Of Functional Ordering On Morphological Chart Exploration, Anant Chawla

All Theses

Morphological Charts are tools used to systematically explore the design solution space. It consists of a table with first column listing the functions that define the design problem and subsequent columns enumerating means (solutions) to achieving each function. Combining one means for each function produces an integrated design concept solution. The potential number of integrated design concept solutions which can be generated from a morphological chart increase when adding rows or columns. However, limited guidelines are available to aid in curbing this combinatorial explosion while identifying high quality concepts. In addition, instructions to systematically arrange functions and means in the …

Clemson Commencement Program, May 2018, Clemson University

Clemson Commencement Programs

No abstract provided.

Use Of Image Analysis As A Tool For Evaluating Various Construction Materials, Venkat Sai Kumar Kothala

All Theses

Characterization of internal structure is necessary to understand the behavior of construction materials under different conditions. Image analysis possesses the technological advantages to better understand construction materials and it also provides information that can help to improve the properties of various construction materials. The purpose of this study was to evaluate the internal structure of various construction materials using image analysis and investigate the infiltration in porous friction course mixtures using thermal image analysis. Automated image processing algorithms were developed to determine the a) long-term binder draindown in asphalt mixtures over time, b) roughness of asphalt mixtures, c) fiber distribution …

In Vitro Study On The Viability For Use Of 3d Printed Valves For Treatment Of Chronic Venous Insufficiency, Kyle Benjamin Yeomans

All Theses

Chronic venous insufficiency (CVI) is a medical disease caused as a result of incompetent vein valves in the lower extremities by the failure to reduce venous pressure during calf exercise. This condition affects 2.5 million individuals in the United States; some estimates are over 6 million due to undiagnosed cases. Healthy venous flow is characterized by the calf muscle producing a lower venous pressure with competent vein valves maintaining this reduced pressure by preventing blood from flowing back into the lower legs; instead of returning to the heart. Conversely, an individual suffering from CVI has partially or fully incompetent vein …

Convex Hulls, Relaxations, And Approximations Of General Monomials And Multilinear Functions, Yibo Xu

All Dissertations

Motivated by a variety of problems in global optimization and integer programming that involve multilinear expressions of discrete or continuous variables, this research derives approxima-tions of multilinear functions, and studies the accuracy of these approximations through worst-case error-analyses:

• The derivation of the convex hull representations of large families of symmetric multilinear polynomials (SMPs) that are defined over box constraints through geometrical exploitation of the polytope symmetry and specially designed facet generation method; and

• The identification of the set of all points at which a nonnegative multilinear polynomial on a box vanishes, which applies to the identification of the …

Properties Of Some Markov Chains On Linear Extensions Of Posets, Kara Stasikelis

All Dissertations

The Tsetlin library is a well-studied Markov model for how an arrangement of books on a library shelf evolves over time. It assumes that, given n books, one book is read and returned at the end of the shelf before another one is picked up. One of the most interesting properties of this Markov chain is that its spectrum can be computed exactly and its eigenvalues are linear in the transition probabilities. This result has been generalized in different ways by various people. In this work, we investigate three generalizations given by the extended promotion Markov chain on linear extensions …

Optimization Models For Sustainable Design And Management Of Biopower Supply Chains, Hadi Karimi

All Dissertations

This dissertation presents optimization models to aid with the sustainable design and management of biopower (biomass cofiring) supply chains. We address three main challenges associated with today’s biopower projects: i) high cost of biomass collection, storage and delivery, ii) inefficiency of the mechanisms used to incentivize biomass usage for generating electricity, and iii) lack of clear understanding about the trade-offs between economic and environmental impacts of biopower supply chains. In order to address the high cost of delivering biomass, we present a novel mixed integer nonlinear program that integrates production and transportation decisions at power plants. Proposed model captures the …

Programming Of Retention Capacity And Release Capabilities Of Propargyl Acrylate Nanoparticles Decorated With Poloxamer Copolymer, Oleksandr Klep

All Dissertations

Nanoparticle based drug delivery offers an advantage over free drug deliv-ery as it allows the manufacturer to introduce various control mechanisms either for targeted delivery or for the controlled release profile of the drug. Systems ca-pable to encapsulate different active molecules, ranging from dyes to drugs, gained a lot of attention in recent years. It was shown that it is possible to create a pro-grammable device that can serve multiple functions ranging from enhanced imag-ing techniques to cancer treatment along with extended drug delivery applications. Therefore methods for fabrication and characterization of the devices that can be used in the …

Essays On Skill-Biased Technological Change And Labor Market Inequality, Yiheng Huang

All Dissertations

There are three chapters in this dissertation. In the first two chapters, I focus on the deceleration of college wage premium growth at national level. In the first chapter, I use a decomposition and counterfactual simulation approach to evaluate three explanations of flattening college wage premium during 2000-2010 and 2000-2015, i.e., demand reversal, polarization and supply change. The simulation results suggest: i. supply change is the most powerful explanation; ii. polarization has expla-natory power but not robust; and iii. demand reversal has little eÿcacy in explaining the fact. By a close look of three explanations, I argue that the “failure” …

Genomic Data Mining For Functional Annotation Of Human Long Noncoding Rnas, Brian L. Gudenas

All Dissertations

Life may have begun in an RNA world, which is supported by the increasingly vital role that RNA has been shown to perform in biological systems. To understand how the genome encodes life, one must look to the transcriptome, the set of all RNA molecules in a cell. The transcriptome illustrates which RNA transcripts are expressed at what times and this orchestrated network of gene expression is responsible for multicellular development. In humans, most genes are noncoding RNAs, meaning that they do not encode proteins. The largest class of noncoding genes are long noncoding RNAs (lncRNAs), RNA transcripts greater in …

Environmental Impact Predictions For Disposal Of Emerging Energy Technologies In Solid Waste Landfills: Application To Lithium Ion Batteries And Photovoltaic Modules, Mary Kayla Kilgo

All Dissertations

As the use of photovoltaic (PV) modules and batteries rapidly increases to meet the growing worldwide energy demand, so does the waste stream of these products at end-of-life (EOL). In locations without sufficient recycling laws or take-back programs, these products could be landfilled with municipal solid waste (MSW). To determine the potential effects from landfill disposal of these products, metal leaching from PV modules and two types of batteries (Li-ion and nickel metal hydride (NiMH)) was studied using the regulatory Toxicity Characteristic Leaching Procedure (TCLP) as well as batch leaching and outdoor column testing. The data from the leaching tests …

Affective Gaming: At The Intersection Of Rhetoric, Affect, And Video Games, Joshua A. Wood

All Dissertations

Affective Gaming is an intervention in the field of game studies, designed to address the lack of racial diversity in games. I examine the role that emotion plays in games by melding game studies and rhetorical theory with affect theory and critical identity studies. I build a theory of gaming that is attuned to the way games provoke emotion in players in order to bring a new understanding of identity to game studies. I then turn towards a theory of game design that uses affect toward a rhetorical end, and finally turn this toward games in the classroom. I also …

Estimating Animal Abundance By Employing An External Experiment To Account For Detection And Count Bias With An Application To Wintering Ducks In The Mississippi Alluvial Valley, April L. Thomas

All Dissertations

A valid concern when structuring an aerial survey of wildlife populations is the presence of visibility bias. Many studies attempt to correct for visibility bias by including additional parameters in estimators for wildlife abundance. Often these parameters are estimated through data collected during the aerial survey. Some, how-ever, have suggested using an external visibility experiment to estimate parameters being used to adjust for visibility bias. This work considers a bias adjusted estimator, proposed by Pearse et al. (2008), in which the bias correction parameters are esti-mated via an external visibility experiment using decoys in place of the live animals. The …

Ontology-Based Domain-Specific Semantic Similarity Analysis And Applications, Xuebo Song

All Dissertations

Millions of text data are penetrating into our daily life. These unstructured text data serve as a huge source of information. Efficient organization and analysis of the overwhelming text can filter out irrelevant and redundant information, uncover invaluable knowledge, thus significantly reduce human effort, facilitate knowledge discovery and enhance cognitive abilities. Semantic similarity analysis among text objects is one of the fundamental problems in text mining including document classifi-cation/clustering, recommendation, query expansion, information retrieval, relevance feedback, word sense disambiguation, etc. While a combination of common sense and domain knowledge could let a person quickly determine if two objects are similar, …

Computational Investigation Of The Morphological Design Dimensions Of Historic Hexagonal-Based Islamic Geometric Patterns, Mostafa Waleed Hashem Alani

All Dissertations

This dissertation examines the morphology of Islamic Geometric Patterns (IGP). Using mixed methods, including the simulation of historical designs and content analysis, this dissertation explores the question of how it is possible to mathematically describe the IGP. The study argues that the compositional analysis of geometry is not solely sufficient to investigate the design characteristics of the IGP, and the underlying mathematics and computational nature of the IGP should be considered when investigating historical IGP.

The study presents a parametric description method that captures the reality of the IGP in numeric form and utilizes the form to derive representational codes …

Evaluation Of Thermal Mechanisms To Predict The Transient Electroplastic Effect In Aluminum And An Investigation Of Electrically Assisted Drilling, Brandt J. Ruszkiewicz

All Dissertations

The objective of this research is twofold: first, to evaluate if the microscale Joule heating theory can predict the transient electroplastic effect in 7075-T6 aluminum. Second, to determine if electrical application can have a significant impact on drilling of 1500MPa steel, and if the operation is predictable using a modified Merchant’s machining model. Both 7075-T6 and 1500 MPa steel are of interest to the automotive industry due to their high strength-to-weight ratios. These metals are important to aid in lightweighting to meet increasingly strict governmental fuel economy standards. However, the strength of the steel makes it difficult to machine in …

Evaluation Of Pedometer Performance Across Multiple Gait Types Using Video For Ground Truth, Ryan Stephen Mattfeld

All Dissertations

This dissertation is motivated by improving healthcare through the development of wearable sensors. This work seeks improvement in the evaluation and development of pedometer algorithms, and is composed of two chapters describing the collection of the dataset and describing the im-plementation and evaluation of three previously developed pedometer algorithms on the dataset collected. Our goal is to analyze pedometer algorithms under more natural conditions that occur during daily living where gaits are frequently changing or remain regular for only brief periods of time. We video recorded 30 participants performing 3 activities: walking around a track, walking through a building, and …

Assessment Of The Structural And Thermal Behavior Of Concrete Masonry Construction Via Experimentally Informed Numerical Models, Marcos Javier Martínez Andino

All Dissertations

This dissertation aims at describing and examining the compressive and out-of-plane behavior and failure patterns of mortarless masonry prisms and walls through experimental tests and numerical models. In addition, the thermal performance of various masonry units is investigated through detailed thermo-fluid dynamic models to contribute to the masonry construction knowledge base. Studies on the behavior of masonry systems are fundamental to understanding their structural and thermal performance. One of the variations of this type of construction is dry-stack masonry, i.e., units laid without mortar between the joints. Despite reducing the time and cost of construction, mortarless construction has not gained …

Quasi-Continuum Non-Local Plate And Shell Models Of Carbon-Based 2d Nanomaterials, Jixuan Gong

All Dissertations

Non-local plate and shell models have attracted much interest in the area of grap-hene and carbon nanotube simulations. This work explores further into this area and aims to provide more accurate and reliable non-local modeling methods to graphene and carbon nanotubes. At first, a semi-analytical model for determining the equilibrium configuration of single wall carbon nanotubes is presented. By taking advantage of the symmetry charac-teristics, a carbon nanotube structure is represented by five independent variables. A line search optimization procedure is employed to determine the equilibrium values of these variables by minimizing the potential energy. With the equilibrium configuration obtai-ned, …

Robust Solutions To Uncertain Multiobjective Programs, Garrett M. Dranichak

All Dissertations

Decision making in the presence of uncertainty and multiple conflicting objec-tives is a real-life issue, especially in the fields of engineering, public policy making, business management, and many others. The conflicting goals may originate from the variety of ways to assess a system’s performance such as cost, safety, and affordability, while uncertainty may result from inaccurate or unknown data, limited knowledge, or future changes in the environment. To address optimization problems that incor-porate these two aspects, we focus on the integration of robust and multiobjective optimization. Although the uncertainty may present itself in many different ways due to a diversity …

Accounting For Uncertainty In Process Optimization Initiatives With Statistical Convolutions And Stochastic Programming Techniques, Russell William Krenek

All Dissertations

The purpose of this dissertation is to explore the uncertainty of process means and variances in order to improve processes with stochastic characteristics due to the complex nature of the underlying probability distributions. First, the gap between the existing conceptual notion of defects per million opportunities (DPMO) as part of process improvement initiatives and its applications to real-world engineering processes is explored. This is important because the current way of obtaining the DPMOs documented in the literature is problematic since it strictly assumes that there will be a shift in the process mean over time, while process variability remains unchanged. …

Nonlinear Optical Phenomena In Emerging Low-Dimensional Materials, Yongchang Dong

All Dissertations

As digital information technologies continue to evolve at much faster rates than the growth of Si-based processors, the encroachment of light-based technologies into computing seems inevitable. With the advent of lasers, photonic crystals, and optical diodes, photonic computing has made significant strides in information technology over the past 30 years. This continuing integration of light into all-optical computing, optoelectronic components, and emerging optogenetic technologies demands the ability to control and manipulate light in a predictable fashion, or by design. Of particular interest, is the passive control and manipulation of light in all-optical switches, photonic diodes, and optical limiting which can …

Clemson Trustees Minutes, 2018 April 20, Clemson University Board Of Trustees

Minutes

No abstract provided.

The Tiger Vol. 112 Issue 10 2018-04-09, Clemson University

Tiger Newspapers 2018

No abstract provided.

"Safety In Numbers" And Bicycle Safety: A Detailed Analysis Of The Denver Metropolitan Area, Rachael Thompson Panik

All Theses

Recently across the US, there has been a push to accommodate and encourage the viability of alternative modes of transportation—especially bicycling. Leaders across all levels of government, trade groups, advocacy and policy groups, and others are promoting different methods to make urban areas more bikeable. Now, as planning practice is moving towards implementing a transportation system that serves different types of travelers, the US faces challenges involved with retrofitting existing automobile-oriented streets.

While implementing bicycle safety initiatives is becoming a popular movement among municipalities, there have been differing opinions on the best way to make cities more bikable in academic …

A Versatile Carbon Nanotube-Based Scalable Approach For Improving Interfaces In Li-Ion Battery Electrodes, Lakshman K. Ventrapragada, Jingyi Zhu, Stephen E. Creager, Apparao M. Rao, Ramakrishna Podila

Publications

Resistive interfaces within the electrodes limit the energy and power densities of a battery, for example, a Li-ion battery (LIB). Typically, active materials are mixed with conductive additives in organic solvents to form a slurry, which is then coated on current collectors (e.g., bare or carbon-coated Al foils) to reduce the inherent resistance of the active material. Although many approaches using nanomaterials to either replace Al foils or improve conductivity within the active materials have been previously demonstrated, the resistance at the current collector active material interface (CCAMI), a key factor for enhancing the energy and power densities, remains unaddressed. …

Factors Affecting The Treatment Of Concussions Within South Carolina Children Aged 5-19, Tyler Crawford

All Theses

The purpose of this research is to evaluate the treatment of concussions for South Carolina school-aged children with an intent of discovering potential disparities in treatment between socioeconomic groups. The results are generated from the entire population of emergency department visits by children aged 5-19 in South Carolina emergency departments, the internal validity of the results is equivalent to the external validity for the population specified. The results found within the dataset constitute the effects of these variables on all children that visited an emergency department in South Carolina with a concussion as a primary or secondary diagnosis between the …

Information Literacy And Mathematics Education Students: A Case Study In Library Instruction, M. H. Albro, K. Megan Sheffield, Anne Grant, Renna Tuten Redd

Publications

Prior to 2016 library instruction for mathematics courses was nonexistent at Shippensburg University. The hiring of the STEM librarian in August 2016 led to an initiative to engage the mathematics faculty and students in using resources and services offered by the Ezra Lehman Memorial Library. This outreach resulted in two sessions of the Fundamentals of Mathematics course coming into the library for instruction in the fall semester. These first sessions found that detailed instruction in how to search and identify articles related to key concepts from the desired journal type was particularly useful to the students; however, these sessions also …

Measuring And Modeling Flow Rates In Tidal Creeks: A Case Study From The Central Coast Of South Carolina, Kathryn K. Ellis, Timothy Callahan, Dianne I. Greenfield, Denise Sanger, Joshua Robinson, Martin Jones

Journal of South Carolina Water Resources

The purpose of this study was to collect site- and condition-specific hydrology data to better understand the water flow dynamics of tidal creeks and terrestrial runoff from surrounding watersheds. In this paper, we developed mathematical models of tidal creek flow (discharge) in relation to time during a tidal cycle and also estimated terrestrial runoff volume from design storms to compare to tidal creek volumes. Currently, limited data are available about how discharge in tidal creeks behaves as a function of stage or the time of tide (i.e., rising or falling tide) for estuaries in the southeastern United States, so this …