Digital Commons Network^™

Intercode Advanced Fuels And Cladding Comparison Using Bison, Frapcon, And Femaxi Fuel Performance Codes, Aaren Rice

Theses and Dissertations

The high density uranium-based fuels are regaining popularity as the current fleet of LWR’s are showing interest in uprating plants to increase accident tolerance and performance. Fuels such as U3Si2, UN, and UC all contain a higher uranium loading and thermal conductivity than that of UO2 making them attractive in combination with an advanced cladding type such as the ceramic SiC cladding. In addition to adding more mass uranium to the core without surpassing current enrichment limits, these advanced fuels and claddings are designed with increased accident tolerance performance in a LOCA type scenario in mind. One of the possible …

Estimating The Water Quality Condition Of River And Lake Water In The Midwestern United States From Its Spectral Characteristics, Jing Tan

Open Access Dissertations

This study focuses on developing/calibrating remote sensing algorithms for water quality retrieval in Midwestern rivers and lakes. In the first part of this study, the spectral measurements collected using a hand-held spectrometer as well as water quality observations for the Wabash River and its tributary the Tippecanoe River in Indiana were used to develop empirical models for the retrieval of chlorophyll (chl) and total suspended solids (TSS). A method for removing sky and sun glint from field spectra for turbid inland waters was developed and tested. Empirical models were then developed using a subset of the field measurements with the …

Monitoring And Modeling The Hydrological Performance Of Extensive Green Roof Systems, Joseph Seidl

Theses and Dissertations

Urban stormwater runoff causes many problems for watersheds located within large metropolitan areas, including such detrimental effects as flooding, erosion, pollution, and the increased risk of combined sewerage overflows. Increased amounts of impervious areas resulting from urban sprawl have also been shown to escalate stormwater flows, which exacerbates water management issues in these metropolitan areas. Water resource engineers have progressively turned toward green infrastructure to solve stormwater problems, and green roof systems represent one type of this green infrastructure. As of current, however, green roof systems are largely underused in as an effective stormwater management tool.

The major factor limiting …

Numerical Simulation And Modeling Of Combustion In Scramjets, Ryan James Clark

Dissertations

In the last fifteen years the development of a viable scramjet has quickly approached the following long term goals: responsive sub-orbital space access; long-range, prompt global strike; and high-speed transportation. Nonetheless, there are significant challenges that need to be resolved. These challenges include high skin friction drag and high heat transfer rates, inherent to vehicles in sustained, hypersonic flight. Another challenge is sustaining combustion. Numerical simulation and modeling was performed to provide insight into reducing skin friction drag and sustaining combustion.

Numerical simulation was used to investigate boundary layer combustion, which has been shown to reduce skin friction drag. The …

Modeling The Feasibility Of Corn Stover Combustion As A Heat Source At Corn Ethanol Plants, Sulekha Tamvada

Theses and Dissertations

Alternative energy sources are of prime interest for most of the nations across the world. Rising fuel prices and depleting petroleum reserves are of serious national and global concern. Bio-fuels if proved feasible for larger scale implementation could become the ideal breakthrough in easing the extensive dependence on fossil fuels and retaining the current engine technology of fossil fuels. Current methods of producing bio-fuels rely heavily on the consumption of non-renewable energy in the production process. Therefore, it is desirable to find renewable alternatives to these non-renewable energy sources.

Although bio-mass based fuels have been tested and proven to be …

Spatial Variation In Fine Sediment And Microbial Transport Along Stream Cross Sections: Implications To Modeling And Monitoring, Thomas Michael Walton

Masters Theses

Spatial variations in suspended concentrations of fine sediment and indicator bacteria in streams is noted as a source of uncertainty in various applications of water quality datasets. Without proper analysis of the persistence and reasoning for this variance in natural systems, a finer resolution of model calibration is necessary to account for spatial variation in stream cross sections. This level of calibration has become of utmost importance due to technological advancements presenting the ability for water quality modeling frameworks to generate a much finer resolution of outputs. While the importance of model calibration has been noted for remediating levels of …

Bankfull Geomorphic Relationships And Hec-Ras Assessment In Small Catchments Of The Cumberland Plateau Ecoregion, Ryan Lee Hodges

Masters Theses

There is a great need for state governments to have effective watershed restoration and mitigation efforts to return degraded ecosystems to a stable, healthy condition. Given the growing investment in stream restoration efforts, there is an urgent need for tools to assess and improve the effectiveness of restoration efforts at local, state, and nationwide scales. In 2000 there was less than ten stream restoration permits provided by the state of Tennessee and has increased each year with almost forty permits issued in 2013. To better achieve successful stream restoration, appropriate channel designs must be used that reflect the hydraulic conditions …

Modeling Water Quality For Switchgrass Crop Production: Implications For Bioenergy Sustainability In East Tennessee, Zachariah Tzvi Seiden

Masters Theses

With passing of the US Energy Independence and Security Act (EISA) of 2007, there has been considerable research conducted on the sustainability of bioenergy crop production in the United States; switchgrass has shown particular potential for bioenergy production in East Tennessee. Many studies evaluating the environmental impact switchgrass has on runoff and water quality use the Soil and Water Assessment Tool (SWAT) for watershed modeling. Because SWAT is a lumped watershed model, it evaluates the result of hydrological processes for each hydrologic response unit (HRU), without accounting for the physical interactions between these HRUs. The Water Erosion Prediction Project (WEPP) …

A Cloud-Based Gssha Index Map Editor Utility For Watershed Decision Support, Jocelynn Marie Anderson

Theses and Dissertations

Preventing damages from flooding is critically important for city managers and planners.Efforts in protecting infrastructure from flooding are often coupled with building hydrologicmodels to provide predictions of what is likely to happen during storm events. As land usechanges, these models must be updated, which is more challenging with sophisticated models. Ateam of researchers from universities in Utah and Wyoming have been developing tools forwater management in the Intermountain West as part of a collaborative NSF research grantcalled CI-WATER. In particular, a free and open source web platform called Tethys has beendeveloped to support the development and hosting of hydrologic web …

Design Of High Temperature Evaporator For Spectroscopic Study Of Equilibrated Vapor Phase Materials, Yarden Bosch

MSU Graduate Theses

This work details the design, assembly, and testing of a high temperature electron beam evaporator for equilibrated vapor phase evaporation of rock oxides for the purpose of astrophysical characterization of extrasolar planetary atmospheres. Infrared spectroscopy of high temperature SiO2 atmosphere created through the electron beam evaporation technique and trapped by argon ice matrix isolation was performed to generate a reference spectrum against which absorption lines in stellar spectra taken during planetary transits can be compared. Studies demonstrate that water inclusions in milky quartz (SiO2) can be used to create H2O/SiO2 equilibrated atmospheres within a Knudsen cell. Modeling of exoplanet spectra …

Detecting, Modeling, And Predicting User Temporal Intention, Hany M. Salaheldeen

Computer Science Theses & Dissertations

The content of social media has grown exponentially in the recent years and its role has evolved from narrating life events to actually shaping them. Unfortunately, content posted and shared in social networks is vulnerable and prone to loss or change, rendering the context associated with it (a tweet, post, status, or others) meaningless. There is an inherent value in maintaining the consistency of such social records as in some cases they take over the task of being the first draft of history as collections of these social posts narrate the pulse of the street during historic events, protest, riots, …

Tethys Platform: A Development And Hosting Platform For Water Resources Web Apps, Nathan R. Swain

Theses and Dissertations

The interactive nature of web applications or “web apps” makes it an excellent medium for conveying complex scientific concepts to lay audiences and creating decision support tools that harness cutting edge modeling techniques. However, the technical expertise required to develop them represents a barrier for would-be developers. The barrier can be characterized by the following hurdles that developers must overcome: (1) identify, select, and install software that meet the spatial and computational capabilities commonly required for water resources modeling; (2) orchestrate the use of multiple FOSS and FOSS4G projects and navigate their differing application programming interfaces (APIs); (3) learn the …

Probing Mechanical Forces In Flagella By Manipulation Of Media Viscosity And Axonemal Structure, Kate Wilson

McKelvey School of Engineering Theses & Dissertations

Cilia and flagella are subcellular organelles used to generate fluid flow or propel the cell. These long cylindrical structures are composed of cytoskeletal elements activated by the unidirectional motor protein dynein. Cilia and flagella are crucial to a number of physiological functions, yet the specific mechanisms of dynein activation and coordination remain unclear. This work investigates the response of the flagellum of Chlamydomonas reinhardtii to increased mechanical loading achieved by variation of media viscosity, and to structural changes achieved by genetic manipulation. Effects of these perturbations are quantified using high spatiotemporal resolution recordings; the results demonstrate mutation-specific changes to the …

Saturable Reactor For Power Flow Control In Electric Transmission Systems: Modeling And System Impact Study, Marcus Aaron Young Ii

Doctoral Dissertations

A Saturable Reactor for Power Flow Control (SRPFC) is a novel application of a concept well known to electronics and power electronics engineers that provides continuous modulation of line reactance by controlling the magnetization in a ferromagnetic core. The novelty of the SRPFC is the target application, which is power flow control in meshed electric power networks. Modulation of the line impedance occurs by altering the current in a DC winding to control the magnetization of the ferromagnetic core, thereby varying the reactance of the AC winding. The deployment of power system equipment, like SRPFC, requires careful planning and study …

Modeling Transportation Planning Applications Via Path Flow Estimator, Seungkyu Ryu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The current practice for modeling in the field of transportation planning is through a four-step travel demand forecasting procedure (i.e., trip generation, trip distribution, mode choice, and traffic assignment); the practice is commonly referred to as the four-step model. Although such a modeling approach has become standard practice, it is deficient in several areas. Specifically, (1) it lacks capability for modeling non-motorized modes such as bicycles, (2) it is inadequate for modeling multiple vehicle types sharing the same roadway space, and (3) it is difficult to apply to small communities with limited resources. This dissertation recognizes these deficiencies and responds …

Microscopic Modeling Of Crowds Involving Individuals With Physical Disability: Exploring Social Force Interaction, Daniel S. Stuart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nearly one quarter of a population is affected by a disability which influences crowd evacuation. Emergencies such as stampede or crowd crush can occur during evacuations. While research has investigated crowd evacuation, little has been researched involving individuals with disabilities. There is a need to understand and model individuals with disabilities in their interaction and how it impacts crowd movement. This dissertation creates a video tracking system to study heterogeneous crowds with individuals with disabilities towards conducting crowd experiments. A large-scale crowd experiment is conducted and the results are analyzed through a developed analysis graphical user interface. Preliminary results of …

Systems Modeling And Economic Analysis Of Photovoltaic (Pv) Powered Water Pumping Brackish Water Desalination For Agriculture, Michael A. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to determine the economic viability of solar powered water pumping and desalination systems for agriculture. Growing global demand for agricultural production has put increased pressure on limited freshwater resources in various locations around the word. Many areas have low quality groundwater resources that have not been utilized for agriculture due to limited availability to electricity, high operational costs of diesel generators and the economics associated with water pumping and processing. Reverse osmosis is a desalination technology that removes salts and other minerals from low-quality water, making it fit for drinking or irrigation. Reduced costs …

Modeling Of Environmentally Assisted Fatigue Crack Growth Behavior, Sree Phani Chandar Reddy

Dissertations

The formation of fatigue cracks and their propagation due to cyclic loading in metals have been a concern for more than hundred years. Since fatigue failure were first reported by the railroad industry in 1840s, tremendous progress has been achieved in understanding fatigue behavior of metals. But fatigue damage is still a concern due to its complex dependency on various environmental variable like humidity, temperature, time and corrosive environment. Although numerous theories and models have been proposed in the past, the effects of environment on fatigue crack growth (FCG) is not completely understood. This dissertation aims to shed light on …

Creep And Shrinkage Behavior Of Fly Ash Based Geopolymer Concrete, Md Rashedul Islam

Doctoral Dissertations

The manuscript presented herein is based on the investigation of the short and long term properties of fly ash based geopolymer concrete (GPC) and their link to fly ash characteristics. Fly ash (FA) exhibits a significantly different particle morphology, which impacts the mechanical properties of the resulting GPC and typically contains impurities that fluctuate from one FA source to another. A key contribution of this research work is the capturing of the variability posed by the FA stockpile with a wide range of physical, chemical, and crystallographic characteristics as a source material to select the GPC mix design. In the …

Identification And Retraining Of Sensorimotor Deficits To Reduce Intention Tremor In Multiple Sclerosis, Megan Heenan

Dissertations (1934 -)

Multiple sclerosis (MS) affects approximately 1 in 1000 Americans and is a significant cause of disability in the United States. One significant contributor to disability in MS is intention tremor, which manifests as an oscillation about the endpoint of a goal-directed movement. A major challenge of treating intention tremor is that the underlying causes of tremor in MS are unknown. In this study, we describe a systems-level computational model and an experimental technique that parameterizes subject-specific deficits in sensory feedback control during goal-directed movements. We used this approach to characterize sensorimotor control and examine how sensory and motor processes are …

Toward A Theory Of Multi-Method Modeling And Simulation Approach, Mariusz A. Balaban

Computational Modeling & Simulation Engineering Theses & Dissertations

The representation via simulation models can easily lead to simulation models too simple for their intended purpose, or with too much detail, making them hard to understand. This problem is related to limitations of the modeling and simulation methods. A multi-method Modeling and Simulation (M&S) approach has the potential for improved representation by taking advantage of methods' strengths and mitigating their weaknesses. Despite a high appeal for using multiple M&S methods, several related problems should be addressed first. The current level of theoretical, methodological, and pragmatic knowledge related to a multi-method M&S approach is limited. It is problematic that there …

Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara

Theses and Dissertations

The goal of this study is to use Modeling and Simulation of Evacuation Plan (MSEP) to support management to execute proper evacuation plan in case of emergency at Hancock Stadium in Illinois State University. Analyses of the research literature and evacuation scenarios are used to build a simulation system that will connect a description of emergency and evacuation situation with its context. It shows how an evacuation plan actually functions. The results of the study will help safety managers to understand the current situations of evacuation according to the specific simulation scenarios. The evacuation simulation is categorized according to the …

Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden

Dissertations, Master's Theses and Master's Reports - Open

The thermoset epoxy resin EPON 862, coupled with the DETDA hardening agent, are utilized as the polymer matrix component in many graphite (carbon fiber) composites. Because it is difficult to experimentally characterize the interfacial region, computational molecular modeling is a necessary tool for understanding the influence of the interfacial molecular structure on bulk-level material properties. The purpose of this research is to investigate the many possible variables that may influence the interfacial structure and the effect they will have on the mechanical behavior of the bulk level composite. Molecular models are established for EPON 862-DETDA polymer in the presence of …

A Methodology For Physically-Based Contact And Meniscus Properties In Rigid-Body Computational Knee Modeling, Stephen Wilson

Open Access Theses & Dissertations

Determining natural inner knee mechanics is a longstanding goal for researchers with applications to prevention and treatment of knee trauma and osteoarthritis. Physical testing has only provided limited information of knee mechanics due to technical challenges and cost. Modeling has been used for decades to obtain some of this otherwise inaccessible information, and recently finite element analysis (FEA) has become a popular means to this end. However, FEA requires time intensive mesh-creation and has large computational requirements. Ideally, model creation should be easy and simulations should be fast to allow for sensitivity analysis. Although allowing easier model creation and offering …

Evaluación De La Huella Hídrica Del Cultivo Lirio Japonés Hemerocallis En La Vereda Ricaurte Del Municipio De Rondón, Boyacá, Yuri Stephani Vanegas Rojas, Lorena Margoth Vera Ramírez

Ingeniería Ambiental y Sanitaria

Colombia es uno de los países que posee una gran riqueza en biodiversidad y fuentes hídricas, siendo uno de los 10 países con mayor disponibilidad de este recurso en el mundo. Los seres humanos gastamos a diario agua para ducharnos, preparar alimentos, lavar los platos o la ropa, o simplemente para beberla directamente, pero también debemos saber que gastamos gran cantidad de agua en todo lo que consumimos (bienes, productos, servicios), ya que en su producción la requieren. La huella hídrica es utilizada como un indicador del uso de agua de los consumidores tanto domésticos como industriales, de forma directa …

Diseño Y Construcción De Un Túnel De Viento Para El Desarrollo De Aplicaciones Académicas En Contaminación Atmosférica, Wendy Johana Olarte Español, Karina Tatiana García Espitia

Ingeniería Ambiental y Sanitaria

Con el fin de desarrollar una herramienta capaz de modelar dinámicamente la dispersión de contaminantes se diseña y construye un túnel de viento de 2,95 m de longitud y 0,73 m de alto, cuya operación consiste en la aplicación de las teorías de similitud desarrolladas a partir de la dinámica atmosférica a un estudio de caso. Debido a los alcances de la modelación, la obtención de los resultados se realiza por métodos visuales utilizando patrones de opacidad como referencia de una concentración determinada, mediante la cual se logran distribuir espacial y objetivamente las medidas de contaminación con un índice de …

Information Propagation Algorithms For Consensus Formation In Decentralized Multi-Agent Systems, Christopher Hollander

Electronic Theses and Dissertations

Consensus occurs within a multi-agent system when every agent is in agreement about the value of some particular state. For example, the color of an LED, the position or magnitude of a vector, a rendezvous location, the most recent state of data within a database, or the identity of a leader are all states that agents might need to agree on in order to execute their tasking. The task of the decentralized consensus problem for multi-agent systems is to design an algorithm that enables agents to communicate and exchange information such that, in finite time, agents are able to form …

Evaluación Del Impacto En Calidad Del Aire, Asociado A Resuspensión De Material Particulado Por La Pavimentación De La Vía Principal De Caracolí - Ciudad Bolívar, Bogotá D.C, Laura Catalina Pinto Herrera, Juan Felipe Méndez Espinosa

Ingeniería Ambiental y Sanitaria

En Bogotá D.C., la Unidad de Planeación Zonal Ismael Perdomo (UPZ- N°69), en la que se encuentra el Barrio Caracoli (zona estrato uno), es catalogada según Decreto 623 de 2011, como área-fuente de contaminación Clase I por PM10 (SDA, 2012), por lo que se hace imperativo según Resolucion 601/2006 (Art 9.), la ejecución de programas que contribuyan a la reducción y control de la resuspensión de material particulado, acciones encaminadas a pavimentación de calles, asi como la implementación de criterios ambientales por parte de entidades públicas como la Unidad Administrativa Especial de Rehabilitación y Mantenimiento Vial (UAERMV), el Instituto de …

Joining And Assembly With Long Fiber Thermoplastic Composites, Danila Kaliberov

All ETDs from UAB

Thermoplastic composites are used extensively in automotive, mass transit, aerospace and other commercial industries. Current industry usage is typically limited to short fiber composites formed by injection molding processes, and continuous fiber reinforced composites through processes such as autoclave molding, filament winding etc. Long fiber thermoplastics (LFT) are a class of composites known for their specific strength, corrosion resistance, impact and damping properties, as well as high production rates, recyclability, and ability for complex part fabrication. The overall objective of this research was to investigate viability of joining and assembly with long fiber thermoplastic composites. This research deals with (1) …

Assessing Biofiltration Pretreatment For Ultrafiltration Membrane Processes, Andrea Cumming

Electronic Theses and Dissertations

An engineered biological filtration (biofiltration) process treating a nutrient-enriched, low-alkalinity, organic-laden surface water downstream of conventional coagulation-clarification and upstream of an ultrafiltration (UF) membrane process was assessed for its treatment effectiveness. The impact of biofiltration pretreatment on UF membrane performance was evaluated holistically by investigating the native source water chemistry and extending the analysis into the drinking water distribution system. The biofiltration process was also compared in treatment performance to two alternative pretreatment technologies, including magnetic ion exchange (MIEX®) and granular activated carbon (GAC) adsorption. The MIEX®, GAC adsorption, and biologically active carbon (BAC) filtration pretreatments were integrated with conventional …