Digital Commons Network^™

Modeling And Control Of Nanoparticle Bloodstream Concentration For Cancer Therapies, Scarlett S. Bracey

Doctoral Dissertations

Currently, the most commonly used treatments for cancerous tumors (chemotherapy, radiation, etc.) have almost no method of monitoring the administration of the treatment for adverse effects in real time. Without any real time feedback or control, treatment becomes a "guess and check" method with no way of predicting the effects of the drugs based on the actual bioavailability to the patient's body. One particular drug may be effective for one patient, yet provide no benefit to another. Doctors and scientists do not routinely attempt to quantifiably explain this discrepancy. In this work, mathematical modeling and analysis techniques are joined together …

Multi-Segment Multi-Criteria Approach For Selection Of Trenchless Construction Methods, Ashikul Islam

Doctoral Dissertations

The research work presented in this thesis has two broad objectives as well as five individual goals. The first objective is to search and determine the minimum cost and corresponding goodness-of-fit by using a different combination of methods that are capable of resolving the problem that exists in multiple segments. This approach can account for variations in unit price and the cost of the design and the inspection associated with multiple methods. The second objective is to calculate the minimum risk for the preferred solution set. The five individual goals are 1) reduction in total cost, 2) application of Genetic …

Green Synthesis, Processing And Characterization Of Nanostructured Metal- And Bi-Metal (Hydroxy-)Stannates, Kuo-Ting Liao

Doctoral Dissertations

Because our limited fossil fuel reserves are being depleted while worldwide energy demands are increasing, an energy crisis has emerged. To mitigate the problem, one major approach is to design and discover new energy materials with superior cost-effectiveness and functionality. Along this line, this dissertation work presents a high-throughput, low temperature and solution-based, green synthesis and processing strategy to enable various nanostructured, metal and bi-metal stannates for future energy storage and harvesting applications.

Specifically, a generic green synthesis route was developed by applying a room temperature, solution-based process for nanostructured copper and copper-zinc hydroxystannate [CuSn(OH)₆(CuHS) and Cu_{x …}

Pf2Α And Pge2 Their Effects On Cell Respiration And Steroidogensis In The Bovine Corpus Luteum, Charlotte B. Bacon

Doctoral Dissertations

Mitochondria are essential to the process of cell respiration and steroidogenesis. Both of these processes impact the viability of the corpus luteum, which is required to maintain early pregnancy. In cattle and other species, progesterone supports gestation, regulates embryogenesis and works in concert with estrogen to maintain the reproductive tract. Many investigators have sought to understand the processes that control regression of the corpus luteum. Two prostaglandins, PGF2a and PGE2, have been implicated in the functioning of this transient gland. It is accepted by most researchers that the primary luteolysin responsible for functional and structural demise of the corpus luteum …

Reliable Integrated Circuits Design And Test At Sub-45nm Technologies, Jifeng Chen

Doctoral Dissertations

The rapid scaling of CMOS technology into the 45nm feature node or below enables the design of higher performance chips through the construction of complex and powerful circuitry. Under area and power constraints similar to those of the past, circuit performance can raise to multi-GHz. The major impulse is that current design can provide an abundance of functionalities with a compacted layout of millions of transistors in a small chip area. However, shrinking transistor dimensions and highly condensed design layout inevitably raise reliability issues including a notable impact on performance, e-specially aging effects and process variations. The timing uncertainties introduced …

Multiple Testing Under Dependence With Approximate Posterior Likelihood And Related Topics, Sairam D. Rayaprolu

Doctoral Dissertations

This dissertation studies large-scale multiple testing which plays an important role in many areas of modern science and technology, such as biomedical imaging and genomic data processing. It has long been recognized that statistical dependence in data poses a significant challenge to large-scale multiple testing. Failure to take the dependence into account can result in severe drop in performance of multiple testing. In particular, the detection power of large-scale multiple tests is known to suffer under dependence when the False Discovery Proportion must be controlled. However, it often happens that the dependence structure is unknown and only a single, albeit …

Adaptive Control For Distributed Multi-Agent Coordination, Jie Luo

Doctoral Dissertations

Distributed multi-agent coordination has drawn increased attention in past decades. Distributed coordination refers to the behavior that a group of agents reaches a certain group coordination with local sensor information and limited inter-agent communications. Depending on the specific task of the distributed multi-agent coordination, a group of agents may move together in a collective manner, maintain a certain formation configuration, or reach an agreement on certain quantity of interest. These coordination problems are called flocking, formation control and consensus, respectively. A majority of existing research on distributed multi-agent coordination mainly considers agents governed by linear dynamics, while few papers address …

Investigation Of Bond-Coat Rumpling In Thermal Barrier Coatings Using Advanced 3d Imaging Techniques, Sina Shahbazmohamadi

Doctoral Dissertations

Thermal barrier coatings (TBCs) are used in gas turbines to reduce the metal temperature for a given operating condition. The temperature drop in the TBC can be exploited by running the engine at a higher firing temperature leading to greater fuel efficiency and/or increased durability. Eventually TBCs spall off. One of the contributing factors to the failure in any TBC system is the surface geometry change of the interface commonly known as Bond-coat rumpling. Though rumpling is a three dimensional behavior, previous efforts of studying rumpling were mainly two-dimensional and/or lacked the 3D quantification of surface geometry change. In this …

Layered Rare Earth And Transition Metal Materials: Synthesis, Modification And Catalytic Application, Yashan Zhang

Doctoral Dissertations

This research contains three parts; the first two parts of this thesis demonstrate the synthesis of rare earth layered materials and their application in biodiesel production as basic heterogeneous catalysts. Different rare earth layered materials were synthesized, characterized, modified, and investigated to find a better catalyst for the biodiesel reactions under mild conditions, and the potassium modified neodymium oxycarbonate was the best among them. Both conventional heating and microwave radiation methods were applied to carry out the transesterification reactions. Different parameters such as reaction time, temperature, reactants ratio, and catalyst amount were also studied in the biodiesel reactions to find …

Chemical Processes Influencing Mercury Transformations And Atmospheric Fluxes In The Atmospheric Boundary Layer In Coastal Regions, Susan Warau Gichuki

Doctoral Dissertations

The atmosphere has been recognized as the major contributor of mercury inputs to terrestrial and aquatic environments. While considerable research on atmospheric concentrations and fluxes of Hg has been carried out in the Northern Hemisphere, this is not the case for the Southern hemisphere, remote islands and parts of the open ocean. In this work, atmospheric Hg concentrations and fluxes were determined for locations in South Africa and Bermuda. The concentrations of Hg and other trace metals (Al, Fe, Mn, Co, Ni, Cu, Zn, Cd and Pb) in precipitation are presented for Pretoria, an urban center and Cape Point, a …

Three-Dimensional Finite Element Analysis Of Solid Oxide Fuel Cell Microstructures, Sushrut S. Vaidya

Doctoral Dissertations

Finite element thermal stress analyses of solid oxide fuel cell (SOFC) electrode microstructure models are performed under various conditions to investigate mechanical integrity of electrodes under thermal loads. Image-based three-dimensional finite element models of electrode microstructures are generated from two-dimensional images of actual electrode cross-sections. Finite element thermal stress analyses of anode models under spatially uniform temperature fields of increasing magnitude are performed, and the effects of temperature-dependent material properties and plasticity on mechanical integrity are investigated. Linear elastic material models are found to underestimate the probability of failure of the anode at high temperatures. Analyses of cathode models are …

Selective Area Laser Deposition For The Purpose Of Ceramic Joining And Repair, Clayton M. Weiss

Doctoral Dissertations

Ceramic materials present joining and repair difficulties that metallic and polymeric materials often lack. The high working temperature and potential for thermal decomposition make techniques such as welding and adhesive bonding unfeasible or impractical. It is possible to create ceramic materials from gas phase precursors through the use of chemical vapor deposition methods. A laser can create localized heat in a substrate and cause the productive decomposition where spatially desired. Through computer motion control, arbitrary patterns of ceramic deposits can be grown. This technique can be used to make free form objects. This process is known as selective area laser …

Wavelet Neural Network Based Very Short-Term Load Forecasting And Prediction Interval Estimation, Che Guan

Doctoral Dissertations

Very short-term load forecasting predicts the loads in electrical power network one or several hours into the future in steps of a few minutes (e.g., five minutes) in a moving window manner based on online data collected every few seconds (e.g., four seconds). In order to quantify forecasting accuracy in real-time, the forecasting process should also estimate good prediction intervals online. Accurate forecasting with prediction intervals is important for resource dispatch and area generation control, and helps power market participants make prudent decisions. It is, however, difficult in view of the noisy data collection process with possible malfunctioning of data …

Titanium-6aluminum-4vanadium For Functionally Graded Orthopedic Implant Applications, Kyle D. Crosby

Doctoral Dissertations

Rising costs of health care are attributed to an increasing number of medical procedures with great complexity and costly instrumentation. Novel materials and devices must be developed to reduce the time, economic cost, and physical pain associated with invasive orthopedic surgery. As well the lifetime of components must be extended to meet the needs of a population with an increasing life expectancy. To prolong the lifetime of an implant device, components should closely mimic the naturally occurring biological structure they are replacing in terms of both mechanical and biological function in order to assimilate undetected in the human body. Studies …

Microstructural Investigation Of Astm A913 Grade 65 Steel Subjected To Shock Loads And Elevated Temperatures, Vincent P. Palumbo

Doctoral Dissertations

The Department of Homeland Security (DHS) funded National Transportation Security Center of Excellence (NTSCOE) at the University of Connecticut focuses on developing and characterizing new materials systems and testing methods for the protection of the country’s infrastructure. This study has provided insight into the mechanical behavior of a high strength low alloy (HSLA) steel, ASTM A913 grade 65, under shock loading conditions and elevated temperatures. Shock loading conditions incorporate deformation rates greater than 10s^-1. Studies have shown that the high rates of deformation, as experienced in an explosion, followed by elevated temperatures such as during a fire, can …

Electrothermal Properties Of Perovskite Ferroelectric Films, Jialan Zhang

Doctoral Dissertations

The electrothermal (electrocaloric and pyroelectric) properties of ferroelectric thin films have many applications in active solid-state cooling and infrared sensing devices. It has been shown experimentally that some thin-film ferroelectrics can produce much larger electrothermal responses than their bulk counterparts. In this work, the electrothermal properties of bulk polar dielectric (ferroelectric and incipient ferroelectric) materials and thin films have been computed using a thermodynamic methodology and the effects of electrical, thermal and mechanical boundary conditions have been illustrated. In particular, the sensitivity of pyroelectric and electrocaloric response to bias and driving fields, lateral clamping and misfit strain, thermal stresses and …

On The Inhibition Of Metal Transfer By Ion Implantation, Luke F. Autry

Doctoral Dissertations

Metal transfer is a phenomena associated with adhesive wear during dry-sliding, boundary lubrication, and elastohydrodynamic lubrication. Coatings, lubricants, and proper wear couple selection are traditionally implemented to reduce metal transfer. Ion implantation is a surface modification technique that has been studied for over 30 years with the goal of improving tribosurfaces. It has the following advantages over traditional techniques: it is a non-equilibrium process in that any element can literally be implanted into a surface, is non-evasive in that bulk material chemistry, structure, dimensionality is unaltered, and coating adhesion is not a factor. The goal of this study was to …

Design, Synthesis, And Application Of Photoactive Complexes Of Biologically Relevant Metals, Celina Gwizdala

Doctoral Dissertations

Photo-labile organic molecules have been broadly utilized as photoprotective groups (PPGs) in “caging compounds”. Inactive caged analyte can be easily introduced in its active form to the system under investigation by photolysis of the PPG. This light induced manipulation permits release of the analyte and allows for spatial and temporal control of its concentration. Photocages presented within utilize specific strategy of metal release that relies on decrease in metal-ligand interaction triggered by delocalization of lone pair of electrons on the metal coordinating nitrogen(s). Synthesis and photochemical properties of nitrobenzhydrol based photocages of Zn²⁺ and Ni²⁺ are presented and …

Hydrologic Data Assimilation For Operational Streamflow Forecasting, Feyera Aga Hirpa

Doctoral Dissertations

Data assimilation (DA) is a method that optimally combines imperfect models and uncertain observations to correct model states using new information acquired from the incoming observations. In recent years, DA has been extensively used for improving the uncertainty of hydrologic prediction, largely due to the emergence of advanced remote sensing tools for observations of soil moisture, river discharge and precipitation. Several DA methods have been explored in hydrology; however the choice and the effectiveness of a specific DA method may vary depending on the model and the observation. The goal of this dissertation study was reducing streamflow forecast uncertainty, and …

Physical Vapor Deposition Of Nanorods From Science To Technology, Stephen P. Stagon

Doctoral Dissertations

The transition from nanoscience to nanotechnology is dependent on a level of scientific maturity. After over 6 decades of nanoscience, this level of maturity has only recently been approached. In this work we first present the current state of nanoscience and nanotechnology in the context of nanofabrication using solution syntheses, chemical vapor deposition and physical vapor deposition. To lay the groundwork for scientific investigation into these three, we choose physical vapor deposition as the prototype due to its high purity and elimination of interfering variables. We then present the emergence of a new level of scientific understanding of nanorod growth …

Stannate Nanomaterials For Sustainable Fire Safety: Processing, Characterization And Application, Gregory M. Wrobel Mr.

Doctoral Dissertations

Statistically, accidental residential and vehicle fires cause ~3000 fatalities, and ~$10 billion in damages per year in the United States. To reduce the hazard, many flammable products are protected with bromated flame-retardants. However, studies have proven their use to pose major environmental and health hazards. A recent EPA mandate calls to phase out common formulations by 2014. To fill the void, incorporation of replacements is critical, however few offer such efficient and versatile protection. This dissertation intends to provide solutions through research and development of non-toxic zinc and calcium hydroxystannate (ZHS, CHS) nanoparticle based flame retardants for common textiles.

Using …

Development Of Reduced Chemical Kinetics For Combustion Simulations With Transportation Fuels, Zhaoyu Luo

Doctoral Dissertations

In reacting flow simulations, detailed chemical kinetics for practical fuels is important for accurate prediction of flames and limit combustion phenomena, such as ignition and extinction in engines. However, detailed chemical kinetic mechanisms are typically large and computationally expensive to apply in practical computational fluid dynamic (CFD) simulations. To resolve this difficulty, various methods for mechanism reduction have been developed over the last few decades to generate reduced mechanisms that can accurately mimic detailed mechanisms. For instance, the method of directed relation graph (DRG) features linear reduction time and was fully automated, rendering it highly efficient for skeletal reduction of …

Electronic And Mechanical Properties Of Nano-Heterostructures From First Principles, Satyesh K. Yadav

Doctoral Dissertations

Reducing the size of components to the nanoscale (e.g., in nano-heterostructures) gives rise to new possibilities. Nano-heterostructures are material systems involving at least two different materials with at least one of them having dimensions less than 100 nm. Such architectures have demonstrated great potential for diverse functionalities within a single nanostructure, which is nonexistent in the individual component materials. Nevertheless, it has been difficult to utilize their full potential due to a lack of understanding of the complex correlation between structure and properties. In this bifocal thesis, state-of-the-art first principles computations are employed to perform systematic studies of (1) the …

On The Integrated Squared Error Of The Linear Wavelet Density Estimator, Lu Lu

Doctoral Dissertations

Archival abstract submitted

Geographical Concentration Of Manufacturing Industries In China —Measurements And Determinants, Zhiqiang Liu

Doctoral Dissertations

This dissertation uses China's Industrial Survey data to explore the degrees and causes of geographical concentration of China's manufacturing industries. The combination indices provide a more sophisticated framework in measuring degree of manufacturing concentration. In addition, determinants of manufacturing concentration are also explored by a series of econometric models. The results show state capital and state subsidies all have significant impact on geographical concentrations of China's manufacturing activities.

A Mathematical Model And Numerical Method For Thermoelectric Dna Sequencing, Liwei Shi

Doctoral Dissertations

DNA sequencing is the process of determining the precise order of nucleotide bases, adenine, guanine, cytosine, and thymine within a DNA molecule. It includes any method or technology that is used to determine the order of the four bases in a strand of DNA. The advent of rapid DNA sequencing methods has greatly accelerated biological and medical research and discovery. Thermoelectric DNA sequencing is a novel method to sequence DNA by measuring the heat that is released when DNA polymerase inserts a deoxyribonucleoside triphosphate into a growing DNA strand. The thermoelectric device for this project is composed of four parts: …

The Measurement Of The Dielectric Constant Of Concrete Pipes And Clay Pipes, David Mcgraw

Doctoral Dissertations

To optimize the effectiveness of the rehabilitation of underground utilities, taking in consideration limitation of available resources, there is a need for a cost effective and efficient sensing systems capable of providing effective, in real time and in situ, measurement of infrastructural characteristics. To carry out accurate non-destructive condition assessment of buried and above ground infrastructure such as sewers, bridges, pavements and dams, an advanced ultra-wideband (UWB) based radar was developed at Trenchless Technology Centre (TTC) and Centre for Applied Physics Studies (CAPS) at Louisiana Tech University (LTU). One of the major issues in designing the FCC compliant UWB radar …

Position-Adaptive Localization Of An Electro-Magnetic Source Using Static And Mobile Wireless Sensor Networks, Miguel D. Gates

Doctoral Dissertations

We present new results in detection and localization of a hidden emitter using Wireless Sensor Networks (WSNs). While this type of problem has been explored extensively, this research combines multiple dynamics, such as mobility and adaptation, to extend the value beyond the typical search mission. Using Micro-Aerial Vehicles (MAVs), in conjunction with multiple static wireless sensor nodes, we create a hybrid sensor network capable of detection and localization of a hidden electro-magnetic (EM) emitter.

In order to localize the emitter, a Received Signal Strength Indicator (RSSI) is used as an approximation of distance from the transmitter to the revolving receivers. …

A Computational Model Of Nanoparticle Transport And Delivery In Tumor Tissue, Vishwa Priya Podduturi

Doctoral Dissertations

Determining the factors that influence the delivery of nanoparticles to tumors and understanding the relative importance of each of these factors is fundamental to optimize the drug delivery process. In this research, a model that combines random walk with the pressure driven flow of nanoparticles in a tumor vasculature is modeled. Nanoparticle movement in a cylindrical tube with dimensions similar to the tumor's blood capillary with a single pore is simulated. Nanoparticle velocities are calculated as a pressure driven flow over imposed to Brownian motion. During the study, the effect of red blood cells (RBC) is also studied by comparing …

Exploration Of Aqueous Interfaces And Their Effect On Ion Behavior, Oneka T. Cummings

Doctoral Dissertations

An in-depth understanding of a wide range of physical, chemical, atmospheric and biological processes can only be achieved after the structure and dynamics of interfaces and the interfacial behavior of aqueous species, such as ions, are thoroughly studied and understood. This dissertation describes computational studies conducted to gain a more comprehensive understanding of such interfaces and the behavior of ions in the bulk and interfacial regions of the (1) air/water interface, and (2) alkane/water interfaces.

At the air/water interface the effect of counterion (sodium cations) charge and the influence of ion pairing on anion (chloride) propensity for the air/water interface …