Physical Sciences and Mathematics Commons^™

Gas-Phase Ion/Ion Reactions Of Biomolecules: An Examination Of Carboxylate Reactivity And Arginine Based Non-Covalent Complexes, Nathan Zachary Barefoot

Open Access Theses

The advent of Electrospray Ionization with the ability to generate multiply charges ions has contributed significantly to the study of gas-phase ion/ion reactions. With the tools available in mass spectrometry it has been shown that these reactions are effective at transforming one type of gaseous ion into another through a series of reactions. This work examines some of these reactions and their application to field of proteomics specifically focusing on the amino acids of arginine and lysine. NHS reagents have been shown to react to both of these molecules with in the gas-phase under different conditions but have relies on …

Systems For Delivering Electric Vehicle Data Analytics, Vamshi Krishna Bolly

Open Access Theses

n the recent times, advances in scientific research related to electric vehicles led to generation of large amounts of data. This data is majorly logger data collected from various sensors in the vehicle. It is predominantly unstructured and non-relational in nature, also called Big Data. Analysis of such data needs a high performance information technology infrastructure that provides superior computational efficiency and storage capacity. It should be scalable to accommodate the growing data and ensure its security over a network. This research proposes an architecture built over Hadoop to effectively support distributed data management over a network for real-time data …

A Model-Based Approach To System-Of-Systems Engineering Via The Systems Modeling Language, Kevin Hughes Bonanne

Open Access Theses

In the field of Systems Engineering, a movement is underway to capture the aspects of a system in a centralized model format instead of various documents. This is the basis of Model Based Systems Engineering (MBSE). In order to better formalize this change, the Systems Modeling Language (SysML) was developed to characterize an ontology for MBSE. Despite the growth of both MBSE practices and SysML tools, they have yet to be rigorously analyzed as to their applicability to the field of System-of-Systems (SoS). This thesis applies SysML to a methodology for System-of-Systems Engineering (SoSE) known as the Wave Model, which …

Correlating Molecular Architecture Of A Radical Polymer Based Copolymer With Its Electrical Transport Properties, Holly Chan

Open Access Theses

The design and synthesis of electrically-conductive macromolecules can lead to significant improvements in the performance of polymer-based energy conversion devices (e.g., thermoelectric devices). For these organic electronic devices, conjugated polymers have dominated the area of conductive polymers; however, these materials are usually synthesized using conditions that lead to poorly-defined polymers. Furthermore, in these increasingly-standard polymers, the charge transport ability of the polymer thin films is largely affected by the degree of crystallinity, which is a difficult property to control in a reproducible fashion. Therefore, we seek to explore a new class of amorphous, non-conjugated polymers containing a stable radical …

Systematic Analysis Of Drainage Events In Free Draining And Managed Subsurface Drainage Systems, Guy Bou Lahdou

Open Access Theses

Understanding the hydrologic controls that regulate outflow from free and managed subsurface drainage systems during drainage events can offer improved insight on the overall functioning and effectiveness of the systems so that they can be better managed or retrofitted to increase their environmental benefits. This study used drainage, precipitation, water table, and soil moisture data from a monitoring site located in east central Indiana to investigate the event hydrology of 22 drainage events in free and managed subsurface drainage systems. Relationships between event drainage volume, drain flow hydrograph metrics, column soil moisture, water table depth, and precipitation characteristics were explored …

Online Naturalization: Evolving Roles In Online Knowledge Production Communities, Jeremy David Foote

Open Access Theses

Web-based peer production communities, like Wikipedia and open source software, have created digital artifacts of growing cultural, financial, and technological importance. Understanding how and why people choose to join these communities, and why they eventually leave them, is therefore an important topic.

We take all of the edit data from six years of activity on the online genealogy wiki WeRelate, and create monthly snapshots of behavior and interaction networks for all 9,570 users who edited the site. We use machine learning to cluster these behavioral snapshots into four "behavioral roles". We identify one of these roles as being indicative of …

Catalysts For Portable, Solid State Hydrogen Genration Systems, Jason Robert Gabl

Open Access Theses

Hydrogen and air powered proton exchange membrane fuel cells are a potential alternative to batteries. In portable power systems, the design requirements often focus on cost efficiency, energy density, storability, as well as safety. Ammonia borane (AB), a chemical hydride containing 19.6 wt. % hydrogen, has a high hydrogen capacity and is a stable and non-toxic candidate for storing hydrogen in portable systems.

Throughout this work, Department of Energy guidelines for low power portable hydrogen power systems were used as a baseline and comparison with commercially available systems. In order to make this comparison, the system parameters of a system …

The Use Of Business Intelligence Techniques In Supply Chain Performance, Jue Gu

Open Access Theses

Who likes data? Businesses are always loyal data followers. Companies analyze various forms of data to maintain businesses and identify their current performance in different areas so they can find business opportunities to improve and obtain more market share in advance (Qrunfleh & Tarafdar, 2012). When Big Data comes to businesses, companies who can take advantage of data the best tend to regularly get more business and customers (Waller & Fawcett, 2013). Collecting, analyzing, and demonstrating data could be essential to a single business, a company's supply chain performance and its sustainability. As an intelligent data processing product in terms …

A Quantitative Framework Of Skill Evaluation Of It Workforce, O Hyun Hwang

Open Access Theses

Every employee has different abilities as well as experience, leading to different results in terms of skills and job performance. In order to improve employee IT skills, organizations should evaluate their employees' skills to understand the current levels of skills and knowledge and to figure out areas where skills are currently lacking.

This study used a different approach than other existing methods to evaluate the IT skills of employees. The research used quantitative empirical data that represents the work experience of employees based on their task history and job positions. The suggested method defines the relationship between IT skills and …

Separation Of On-Column Labeled Model Proteins With Packed Capillary Electrophoresis, Yingxu Hao

Open Access Theses

Protein drugs are increasingly developed in the pharmaceutical company. Under the regulation of FDA, high purity of therapeutic proteins needs to be maintained. Before putting those drugs in the market, fast and efficient method is in need to achieve homogeneity. Traditionally, polyacrylamide gel electrophoresis (PAGE), capillary electrophoresis (CE), and size-exclusion chromatography (SEC) are used for the purification process. These methods have the disadvantages of low time and cost efficiency, and this quality assurance process has become the bottleneck of production. In our group, sub-micron silica colloidal particles with polyacrylamide layer on the surface are packed inside capillaries to increase the …

Using The Microsoft Kinect To Assess Human Bimanual Coordination, Joshua James Liddy

Open Access Theses

Optical marker-based systems are the gold-standard for capturing three-dimensional (3D) human kinematics. However, these systems have various drawbacks including time consuming marker placement, soft tissue movement artifact, and are prohibitively expensive and non-portable. The Microsoft Kinect is an inexpensive, portable, depth camera that can be used to capture 3D human movement kinematics. Numerous investigations have assessed the Kinect's ability to capture postural control and gait, but to date, no study has evaluated it's capabilities for measuring spatiotemporal coordination. In order to investigate human coordination and coordination stability with the Kinect, a well-studied bimanual coordination paradigm (Kelso, 1984, Kelso; Scholz, & …

Physical And Chemical Attributes Of A Genetically Modified Fruit Pectin, Carl Patrick Littrell

Open Access Theses

Pectin is an important polymer used in the food industry as a thickening and gelling agent. Though pectin is ubiquitous in plants, chemical and structural differences among pectin molecules prevent most from being viable for industrial use. Enzymes found naturally in fruit cell walls during the ripening process impair many desirable attributes of fruit pectins, rendering them unsuitable for industrial applications. Pectin methylesterase (PME) is one such enzyme whose expression can be altered during ripening through the use of recombinant genetic engineering. Reduction in levels of PME results in increased degree of methylation and molecular size of pectin, greatly increasing …

Investigation Into The Control Of Melittin Secondary Structure And Antimicrobial Activity, Zachary B. Molinets

Open Access Theses

Antimicrobial resistance has been an exponentially growing problem since the discovery of antibiotics. Antibiotics have been misused for many years and this misuse has grown into a real problem for the medical community. While there are countless safeguards to prevent infection by a resistant strain of bacteria, there are still many plagued by it and must be treated with sometimes dangerous antibiotics. Melittin, along with many other peptides, contain potent antimicrobial properties, but are also toxic toward enthrocytes. The control of the secondary structure of peptides provides the key to adjusting their activity.

Study Of A Generalized Empirical Model For Predicting Pressure Drop For Internal Flows, Tejas Anup Pant

Open Access Theses

A generalized empirical model for estimating the pressure drop across a channel for a given massflow rate is studied through computational fluid dynamics (CFD) simulations. It is observed that for developing laminar and turbulent flow through channels and pipes of arbitrary cross-section, the variation in the pressure drop between any two points in the flow direction with massflow rate can be well approximated by a second degree expression in massflow rate which is referred to as the empirical model in this study. In the first part of this study, a correlation between the pressure gradient and the massflow rate is …

Experimental Study Of Unsteady Heat Release In An Unstable Single Element Lean Direct Injection (Ldi) Gas Turbine Combustor, Varun S. Lakshmanan

Open Access Theses

In an effort to curb emissions from gas turbine engines, many low emission engine concepts have been developed. Among the most promising of these is the LDI (Lean Direct Injection). These systems operate at relatively low equivalence ratios close to blowout and are prone to instabilities. Combustion instabilities can reduce the life of the combustor by causing large pressure fluctuations and enhanced heat release to the walls of the combustor and reduce the efficiency of the engines. The understanding of combustion instabilities is vital to the implementation of such systems. Combustion instabilities are studied in an self-excited single element gas …

Preparation & Characterization Of High Purity Cu2 Znsn(Sxse1-X)4 Nanoparticles, Bethlehem G. Negash

Open Access Theses

Research in thin film solar cells applies novel techniques to synthesize cost effective and highly efficient absorber materials in order to generate electricity directly from solar energy. Of these materials, copper zinc tin sulfoselenide (Cu₂ZnSn(S_xSe_1-x) ₄) nanoparticles have shown great promise in solar cell applications due to optimal material properties as well as low cost & relative abundance of materials.^1,2 Sulfoselenide nanoparticles have also a broader impact in other industries including electronics³, LED ⁴, and biomedical research⁵. Of the many routes of manufacturing these class of semiconductors, …

Modeling Spatial Covariance Functions, Inkyung Choi

Open Access Dissertations

Covariance modeling plays a key role in the spatial data analysis as it provides important information about the dependence structure of underlying processes and determines performance of spatial prediction. Various parametric models have been developed to accommodate the idiosyncratic features of a given dataset. However, the parametric models may impose unjustified restrictions to the covariance structure and the procedure of choosing a specific model is often ad-hoc. In the first part of the dissertation, a new nonparametric covariance model that can avoid the choice of parametric forms is proposed. The estimator is obtained via a nonparametric approximation of completely monotone …

Synthesis And Dna-Binding Studies With Two Stericallyfriendly Porphyrin Frameworks, Srijana Ghimire

Open Access Dissertations

Peripheral substituents on cationic porphyrins play a significant role during binding with DNA hosts. Possible applications of these systems in photodynamic therapy as well as in anti-bacterial and anti-cancer therapies motivate the binding studies. For characterizing DNA binding motifs different methods are useful including absorption, emission, and circular dichroism spectroscopies, as well as viscometry and X-ray crystallography. With the classic H₂ T₄ porphyrin, or 5,10,15,20-tetra(N-methylpyridinium-4-yl)porphyrin, the mode of binding varies with the base composition of the DNA host. The porphyrin binds adenine-thymine rich sequences externally whereas intercalation occurs in guanine-cytosine rich sequences. The McMillin group has made some …

Energy Efficient Hybrid Computing Systems Using Spin Devices, Mrigank Sharad

Open Access Dissertations

Emerging spin-devices like magnetic tunnel junctions (MTJ's), spin-valves and domain wall magnets (DWM) have opened new avenues for spin-based logic design. This work explored potential computing applications which can exploit such devices for higher energy-efficiency and performance. The proposed applications involve hybrid design schemes, where charge-based devices supplement the spin-devices, to gain large benefits at the system level. As an example, lateral spin valves (LSV) involve switching of nanomagnets using spin-polarized current injection through a metallic channel such as Cu. Such spin-torque based devices possess several interesting properties that can be exploited for ultra-low power computation. Analog characteristic of spin …

Fundamental Studies On Copper Zeolites For Catalytic No X Abatement, Anuj Arun Verma

Open Access Dissertations

Stringent regulations in mobile NOx emissions have resulted in the development of Standard Selective Catalytic Reduction (SCR) as the dominant NOx abatement technology in lean burn diesel engines. Standard SCR is a reaction of nitric oxide (NO) with ammonia (NH₃), in the presence of oxygen (O ₂) to form nitrogen (N₂) and water (H₂O). Copper containing zeolites show commercially viable SCR performance. Cu-SSZ-13 (CHA framework), a member of this family, is a preferred catalyst for SCR applications because it shows exceptional hydrothermal stability in addition to commercially viable SCR performance. Our work focuses …

Optical Position Sensing In Free Space Optical Communication, Muhammad Salman Bashir

Open Access Theses

In this thesis the performance of three estimators, (center of gravity, template matching and maximum likelihood (MLE)) to estimate the center of the beam on a photoemissive receiver array in a Free Space Optics (FSO) system, is compared in terms of mean square error. Simulations have been conducted in Matlab by generating a two dimensional nonhomogeneous Poisson process, and, mean square error is computed for three estimators. The cases of continuous and discrete arrays are also considered for various levels of signal-to-noise (SNR) ratio. Simulations have shown that the MLE gives the least mean squared error and especially performs significantly …

Field To Flight: A Techno-Economic Analysis Of Stover To Aviation Biofuels Supply Chain, Amanda C. Bittner

Open Access Theses

Greenhouse gas emissions have been a growing concern. The transportation sector contributes to one-third of GHG emissions in the United States from fossil fuel burning. The Renewable Fuel Standard set a requirement for 16 billion gallons (ethanol equivalent) of cellulosic biofuels to be used in the market. Aviation biofuels can help to meet both of these problems as well as improve U.S. energy security.

Investment in the biofuel industry carries a lot of risk. The biofuel industry is run by the private sector, but can be incentivized by government. Cellulosic biofuels carry even more risk than first generation biofuels, because …

Assessing Inland Hazards Associated With Hurricanes In The U.S. Atlantic Basin, Dereka Latrese Carroll

Open Access Theses

The skill of tropical-cyclone (TC) track forecasts has steadily improved over the past decades, as has the understanding of TC risk in coastal regions. However, there is still much to be learned about the TC risk in inland regions, which is complicated by the presence of coastal evacuees, and includes hazards such as inland flash flooding and tornadoes. This was exemplified by Hurricane Ivan (2004), which spawned 118 tornadoes and produced significant rainfall amounts contributing to flooding inland. Ivan was responsible for 25 deaths in the U.S. and $18.8 billion (2004 USD) in damages. As part of a larger effort …

A Novel Microgrid Demand-Side Management System For Manufacturing Facilities, Terance Jerome Harper

Open Access Theses

Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable.

For this research, a manufacturing process that had approximately …

High Temperature Flooded Expansion For Solar Thermal Power Generation, Nelson Alexander James

Open Access Theses

Even though solar power usage has seen rapid growth over the past decade, fossil fuel generation sources are still generally a less expensive means of producing power. The Liquid-Flooded Ericsson Cycle (LFEC) was investigated as a high efficiency power cycle for reducing the cost of concentrated solar power (CSP) plants and helping to address this cost disparity. High temperature flooded expansion was identified as one of the main challenges in regards to utilizing the LFEC as a power cycle. Thermodynamic models were developed to help assess the performance of the LFEC and a load stand was constructed to test a …

Changes In Tundra Plant And Soil Organic Geochemical Composition In Response To Long-Term Increased Winter Precipitation In N. Alaska, Olivia Miller

Open Access Theses

Tundra ecosystem soils store half of the global soil organic carbon (SOC) pool and have the potential to release large amounts of greenhouse gases, primarily CH₄ and CO₂. As climates warm and permafrost thaws, the emissions of these gases as organic matter decomposition rates increase may become increasingly important to the chemistry of the atmosphere. Increases in precipitation that accompany warming, may shift tundra vegetative composition from moss/graminoid- to shrub-dominated systems. These vegetation shifts may result in important feedback effects as altered plant and litter chemistry may affect SOC storage in soils. Questions investigated include: 1) How …

Nickel Aluminum Shape Memory Alloys Via Molecular Dynamics, Keith Ryan Morrison

Open Access Theses

Shape memory materials are an important class of active materials with a wide range of applications in the aerospace, biomedical, and automobile industries. These materials exhibit the two unique properties of shape memory and superelasticity. Shape memory is the ability to recover its original shape by applying heat after undergoing large deformations. Superelasticity is the ability to undergo large, reversible deformations (up to 10%) that revert back when the load is removed. These special properties originate from a reversible, diffusionless solid-solid phase transformation that occurs between a high temperature austenite phase and a low temperature martensite phase. The development of …

Synthesis And Characterization Of Crystalline Iron Nanoparticles From Zerovalent Iron Sandwich Complexes, Anh Tue Nguyen

Open Access Theses

In this project we present a systematic study on the synthesis of crystalline iron nanocubes by thermal decomposition of an iron sandwich complex, ( π-C₅H₅)Fe⁰(π-C ₆H₇), in the presence of oleylamine and oleylamine.HCl as surfactants and n-decane as a solvent. The presence of oleylamine.HCl is essential for the reproducible formation of crystalline iron cores.^ Reaction parameters such as temperature, surfactant concentration, effect of counterion, and organoiron reagent structure were investigated in order to obtain iron nanoparticles with uniform size and shape. The nanoparticles, which were characterized by …

Computer Vision Aided Lip Movement Correction To Improve English Pronunciation, Shuang Wei

Open Access Theses

This paper explored the possibility of improving the pronunciation of English as a Foreign Language (EFL) learners by correcting their mouth-lip movement through visual feedback methods. As an EFL learner, I noticed that while learning pronunciation, for some words, the mouth-lip movement (e.g., opening size and duration) will affect the final pronunciation. A prototype system was developed to compare the standard pronunciation mouth shape movement with a user's pronunciation mouth shape movement and give visual feedback to users. Using computer vision technology, the mouth shape movement of standard pronunciation is extracted into moving contours. The user's mouth movement is video …

The Optimization Of Emergency Call Systems Using Simulation Modeling, Evar C. Jones

Open Access Theses

Using computer simulation modeling, this research assessed the effectiveness and response times when using a mobile safety system versus an emergency call box when reporting an emergency at Purdue University, West Lafayette's Engineering Mall area, attempting to answer the first question "What emergency call system is more effective: a mobile safety system or an emergency call box?" The second question asks "What emergency call system has a faster response time: a mobile safety system or an emergency call box?" A discrete event simulation model of the emergency call service is used. The outcome of the study was that the mobile …