Engineering Commons^™

Novel Convergence Results In Nonlinear Filtering, Jennifer Lynn Bonniwell

Dissertations (1934 -)

In this dissertation, the discrete-time extended Kalman filter is analyzed for its ability to attenuate finite-energy disturbances, known as the H-infinity property. Though the extended Kalman filter is designed to be a locally optimal minimum variance estimator, this dissertation proves that it has additional properties, such as H-infinity. This analysis is performed with the extended Kalman filter in direct form. Since this form reduces assumptions placed on the system in previous works on convergence and H-2 properties of the extended Kalman filter, the extended Kalman filter used as a nonlinear observer for noise-free models is revisited using the direct form …

Injury Risk Assessment Of The Femur In Children With Osteogenesis Imperfecta, Jessica Marie Fritz

Dissertations (1934 -)

Osteogenesis imperfecta (OI) is a genetic disorder characterized by increased bone fragility and decreased bone mass, which leads to high rates of bone fracture. OI has a prevalence of 1/5,000 to 1/10,000 in the United States. About 90% of persons with OI have a genetic mutation in the coding for collagen type I, which is the major protein of connective tissues, including bone. While its prevalence classifies it as a rare disease, it is the most common disorder of bone etiology. Until recently, little was known about the mechanics and materials of OI bone or their impact on fracture risk. …

Proportionate Adaptive Filtering For Block-Sparse System Identification, Jianming Liu, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new family of proportionate normalized least mean square (PNLMS) adaptive algorithms that improve the performance of identifying block-sparse systems is proposed. The main proposed algorithm, called block-sparse PNLMS (BS-PNLMS), is based on the optimization of a mixed norm of the adaptive filter's coefficients. It is demonstrated that both the NLMS and the traditional PNLMS are special cases of BS-PNLMS. Meanwhile, a block-sparse improved PNLMS (BS-IPNLMS) is also derived for both sparse and dispersive impulse responses. Simulation results demonstrate that the proposed BS-PNLMS and BS-IPNLMS algorithms outperformed the NLMS, PNLMS and IPNLMS algorithms with only a modest …

Comparison Of Binary And Multi-Level Logic Electronics For Embedded Systems, Shirly M. Damti, Steve Eugene Watkins, R. Joe Stanley

Electrical and Computer Engineering Faculty Research & Creative Works

Embedded systems are dependent on low-power, miniaturized instrumentation. Comparator circuits are common elements in applications for digital threshold detection. A multi-level, memory-based logic approach is in development that offers potential benefits in power usage and size with respect to traditional binary logic systems. Basic 4-bit operations with CMOS gates and comparators are chosen to compare circuit implementations of binary structures and quaternary equivalents. Circuit layouts and functional operation are presented. In particular, power characteristics and transistor count are examined. The potential for improved embedded systems based on the multilevel, memory-based logic is discussed.

Deformable Contour Models For Digitizing A Printed Brainstem Atlas, Nirmal J. Patel

Electrical & Computer Engineering Theses & Dissertations

The brainstem is a part of the brain that is connected to the cerebrum and the spinal cord. Ten out of twelve pairs of cranial nerves emerge from the brainstem. The cranial nerves transmit information between the brain and various parts of the body. Due to its anatomical and physiological relevance, a descriptive digital brainstem is important for neurosurgery planning and simulation. For both of these neurosurgical applications, the complexity of the brainstem requires a digital atlas approach to segmentation that maps intensities to tissues rather than less descriptive voxel or surface-based approaches. However, a descriptive brainstem atlas with adequate …

Non-Thermal Atmospheric-Pressure Plasma For Sterilization Of Surfaces And Biofilms, Johanna Ursula Neuber

Electrical & Computer Engineering Theses & Dissertations

Bacterial resistance to antimicrobial methods is a critical issue in many fields of medicine. This work describes the studies performed to characterize and optimize the bacterial inactivation effects of a non-thermal atmospheric-pressure plasma brush and plasma jet on a laminate surface inoculated with Acinetobacter baumannii and Staphylococcus aureus, and a cultivated Enterococcus faecalis biofilm, respectively. These treatments are pilot studies for eventual application to surface sterilization in hospitals and root canal disinfection. To evaluate bacterial inactivation, after treatment and recovery, the bacterial colony forming units (CFUs) are counted. Several different methods are used to optimize the antimicrobial effect. For the …

Carbon And Boron Nitride Nanotube Fabricated Supercapacitors, Derek Christian Demuth

Electrical & Computer Engineering Theses & Dissertations

The fabrication of supercapacitor devices consisting of boron nitride nanotubes (BNNTs) and carbon nanotubes (CNTs) has great theoretical capabilities of high specific capacitance, energy density, and power density. Various methods of dispersion and deposition are utilized to optimize such supercapacitors with BNNTs and CNTs, and also to produce devices with only CNTs to use as a benchmark. In addition to capacitance measurements, BNNTs that were exposed to nitric acid were compared to fabricated devices without acid exposure.

Dispersion has been accomplished through the trial of many solvents and surfactants for both CNTs and BNNTs. Deposition techniques that are utilized rely …

Sparse Coding Based Feature Representation Method For Remote Sensing Images, Ender Oguslu

Electrical & Computer Engineering Theses & Dissertations

In this dissertation, we study sparse coding based feature representation method for the classification of multispectral and hyperspectral images (HSI). The existing feature representation systems based on the sparse signal model are computationally expensive, requiring to solve a convex optimization problem to learn a dictionary. A sparse coding feature representation framework for the classification of HSI is presented that alleviates the complexity of sparse coding through sub-band construction, dictionary learning, and encoding steps. In the framework, we construct the dictionary based upon the extracted sub-bands from the spectral representation of a pixel. In the encoding step, we utilize a soft …

Thin Film Studies Toward Improving The Performance Of Accelerator Electron Sources, Md Abdullah Al Mamun

Mechanical & Aerospace Engineering Theses & Dissertations

Future electron accelerators require DC high voltage photoguns to operate beyond the present state of the art to conduct new experiments that require ultra-bright electron beams with high average current and higher bunch charge. To meet these demands, the accelerators must demonstrate improvements in a number of photogun areas including vacuum, field emission elimination in high voltage electrodes, and photocathodes. This dissertation illustrates how these improvements can be achieved by the application of suitable thin-films to the photogun structure for producing ultra-bright electron beams.

This work is composed of three complementary studies. First, the outgassing rates of three nominally identical …

A Hybrid Position Feedback Controller For Bistable Structures, Mehmet R. Simsek

Mechanical & Aerospace Engineering Theses & Dissertations

Bistability is the property of structures showing the ability to attain two statically stable states. Due to dynamic and static advantages such as no energy demand at stable positions and providing higher deflections compared to a monostable structure, bistability may be appealing in control surface design for aircraft structures and load alleviation for wind turbine blades. The dynamics of bistable structures is nonlinear because of the snap-through occurring during the cross-well oscillation between two stable states. A new control strategy called hybrid position feedback control is developed based on the conventional positive position control to exploit linear dynamics of bistable …

Modeling Shock Waves Using Exponential Interpolation Functions With The Least-Squares Finite Element Method, Bradford Scott Smith Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

The hypothesis of this research is that exponential interpolation functions will approximate fluid properties at shock waves with less error than polynomial interpolation functions. Exponential interpolation functions are derived for the purpose of modeling sharp gradients. General equations for conservation of mass, momentum, and energy for an inviscid flow of a perfect gas are converted to finite element equations using the least-squares method. Boundary conditions and a mesh adaptation scheme are also presented. An oblique shock reflection problem is used as a benchmark to determine whether or not exponential interpolation provides any advantages over Lagrange polynomial interpolation. Using exponential interpolation …

Long-Term Quantitative Study Of Wind-Tunnel Balance Calibrations Across Multiple Calibration Systems, Ryan James Callahan

Mechanical & Aerospace Engineering Theses & Dissertations

Internal strain-gauge balances are multi-dimensional force transducers widely employed in wind tunnels to obtain accurate aerodynamic force and moment data on an aircraft model. Balances are calibrated periodically to assure measurement accuracy. The calibration provides a mathematical model relating the forces applied to the balance and the output signal from the balance. Currently, there are multiple types of internal strain-gauge balances used in wind-tunnel testing as well as multiple methods by which balances are calibrated. Because of the differences in the hardware and methodologies used to calibrate a wind-tunnel balance, it is hard to quantify the differences seen between the …

Secondary Electron Emission From Plasma Processed Accelerating Cavity Grade Niobium, Miloš Bašović

Mechanical & Aerospace Engineering Theses & Dissertations

Advances in the particle accelerator technology have enabled numerous fundamental discoveries in 20th century physics. Extensive interdisciplinary research has always supported further development of accelerator technology in efforts of reaching each new energy frontier.

Accelerating cavities, which are used to transfer energy to accelerated charged particles, have been one of the main focuses of research and development in the particle accelerator field. Over the last fifty years, in the race to break energy barriers, there has been constant improvement of the maximum stable accelerating field achieved in accelerating cavities. Every increase in the maximum attainable accelerating fields allowed for higher …

Idpal - Input Decoupled Partially Adiabatic Logic Family: Theory And Implementation Of Side-Channel Attack Resistant Circuits, Matthew Edward Mcallister

Electrical & Computer Engineering Theses & Dissertations

The Input Decoupled Partially Adiabatic Logic (IDPAL) family was developed by Cutitaru to consume less power than other logic families as well as producing a resistance to side-channel attacks. With modifications made to IDPAL, the side-channel attack resistance is being revisited and quantified. The three logic families are compared in the work are CMOS, 2N2P, and IDPAL. An AND/NAND gate was created using each logic family and compared with two tests: 1) a simulated side-channel attack and 2) an energy analysis. In this work, a side-channel attack is the ability to predict the inputs of a logic circuit based on …

Nonlinear Flight Control Design Using Backstepping Methodology, Thanh Trung Tran

Mechanical & Aerospace Engineering Theses & Dissertations

The subject of nonlinear flight control design using backstepping control methodology is investigated in the dissertation research presented here. Control design methods based on nonlinear models of the dynamic system provide higher utility and versatility because the design model more closely matches the physical system behavior. Obtaining requisite model fidelity is only half of the overall design process, however. Design of the nonlinear control loops can lessen the effects of nonlinearity, or even exploit nonlinearity, to achieve higher levels of closed-loop stability, performance, and robustness. The goal of the research is to improve control quality for a general class of …

Concurrent Spatial Mapping Of The Viscoelastic Behavior Of Heterogeneous Soft Materials Via A Polymer-Based Microfluidic Device, Wenting Gu

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation presents a novel experimental technique, namely concurrent spatial mapping (CSM), for measuring the viscoelastic behavior of heterogeneous soft materials via a polymer-based microfluidic device. Comprised of a compliant polymer microstructure and an array of electrolyte-enabled distributed resistive transducers, the microfluidic device detects both static and dynamic distributed loads. Distributed loads deform the polymer microstructure and are recorded as resistance changes at the locations of the transducers.

The CSM technique identifies the elastic modulus of soft materials by applying a precisely controlled indentation depth using a rigid probe to a sample placed on the device. The spatially-varying elastic modulus …

Experimental Investigation Of Turbulent Structures And Non-Equilibrium Effects In Axial Wake Vortices Via Particle Image Velocimetry, Jeffry William Ely

Mechanical & Aerospace Engineering Theses & Dissertations

Vortices are a common phenomenon in fluid flows that arise as kinetic energy dissipates into heat via viscous interaction. They arise naturally at large scales in the form of dust devils, tornadoes, and as a counter-rotating vortex pair in the wake of aircraft. It is important to understand the conditions leading to their formation, their duration, and their dissipation in order to forecast or prevent undesirable effects. Among these deleterious effects is a decrease in safety of aircraft operations in the wake of other aircraft, an extremely common situation at airports around the world. A large number of mathematical models …

Notes On Contributions To The Science Of Rare Earth Element Enrichment In Coal And Coal Combustion Byproducts, James C. Hower, Evan J. Granite, David B. Mayfield, Ari S. Lewis, Robert B. Finkelman

Center for Applied Energy Research Faculty and Staff Publications

Coal and coal combustion byproducts can have significant concentrations of lanthanides (rare earth elements). Rare earths are vital in the production of modern electronics and optics, among other uses. Enrichment in coals may have been a function of a number of processes, with contributions from volcanic ash falls being among the most significant mechanisms. In this paper, we discuss some of the important coal-based deposits in China and the US and critique classification systems used to evaluate the relative value of the rare earth concentrations and the distribution of the elements within the coals and coal combustion byproducts.

Ceramic-Ceramic Welds, Greg Hilmas, William Fahrenholtz, Jeremy Lee Watts, Derek Scott King, Sean Landwehr

Materials Science and Engineering Faculty Research & Creative Works

A method of producing a ceramic weld, including identifying a ceramic first surface an a ceramic second surface to he bonded together, maintaining a non-oxidizing atmosphere over the first and second surfaces, and engaging the first and second surfaces to define a joint, An arc is generated between an electrode and the joint to create a liquid phase, and the liquid phase is cooled to yield a solid fusion layer, wherein the first and second surfaces are joined in the fusion layer.

Ensemble Forecasts: Probabilistic Seasonal Forecasts Based On A Model Ensemble, Hannah Aizenman, Michael D. Grossberg, Nir Y. Krakauer, Irina Gladkova

Publications and Research

Ensembles of general circulation model (GCM) integrations yield predictions for meteorological conditions in future months. Such predictions have implicit uncertainty resulting from model structure, parameter uncertainty, and fundamental randomness in the physical system. In this work, we build probabilistic models for long-term forecasts that include the GCM ensemble values as inputs but incorporate statistical correction of GCM biases and different treatments of uncertainty. Specifically, we present, and evaluate against observations, several versions of a probabilistic forecast for gridded air temperature 1 month ahead based on ensemble members of the National Centers for Environmental Prediction (NCEP) Climate Forecast System Version 2 …

The Impact Of Damage Accumulation On The Kinetics Of Network Strength Recovery For A Physical Polymer Gel Subjected To Shear Deformation, Travis Thornell, Krithika Subramaniam, Kendra Erk

School of Materials Engineering Faculty Publications

Shear rheophysical experiments were used to quantify the kinetics of strength recovery of model thermoreversible polymer gels that were fractured and ultimately sheared to different total magnitudes of strain (700 and 4000%) before resting for set periods of time. Relationships between the amount of strength recovered and the normalized ratio of resting times to characteristic relaxation times were developed. It was found that gels displayed fully healed networks within timescales that were 2-3 orders of magnitude greater than the gel’s characteristic relaxation time. Gels deformed to 700% applied strain either healed slower at lower gel concentrations as compared to experiments …

More Investigations In Capillary Fluidics Using A Drop Tower, Andrew Paul Wollman, Mark M. Weislogel, Brentley M. Wiles, Donald Pettit, Trevor Snyder

Mechanical and Materials Engineering Faculty Publications and Presentations

A variety of contemplative demonstrations concerning intermediate-to-large length scale capillary fluidic phenomena were made possible by the brief weightless environment of a drop tower (Wollman and Weislogel in Exp Fluids 54(4):1, 2013). In that work, capillarity-driven flows leading to unique spontaneous droplet ejections, bubble ingestions, and multiphase flows were introduced and discussed. Such efforts are continued herein. The spontaneous droplet ejection phenomena (auto-ejection) is reviewed and demonstrated on earth as well as aboard the International Space Station. This technique is then applied to novel low-g droplet combustion where soot tube structures are created in the wakes of burning drops. …

Interactive Spatiotemporal Analysis Of Oil Spills Using Comap In North Dakota, Yong Shin Park, Hamad Al-Qublan, Eunsu Lee, Gokhan Egilmez

Mechanical and Industrial Engineering Faculty Publications

The aim of the study is to analyze the oil spill pattern from various types of incidents and contaminants to determine the extent that incident data can be used as a baseline to prevent hazardous material releases and improve response activities at a state level. This study addresses the importance of collecting and sharing oil spill incidents as well as analytics using the data. Temporal, spatial and spatiotemporal analysis techniques are employed for the oil-spill related environmental incidents observed in the state of North Dakota, United States of America, from 2000 to 2014, as a result of the oil boom. …

X-Ray Absorption Spectroscopy Study Of The Effect Of Rh Doping In Sr2Iro4, C. H. Sohn, Deok-Yong Cho, C. -T. Kuo, L. J. Sandilands, Tongfei Qi, Gang Cao, T. W. Noh

Center for Advanced Materials Faculty Publications

We investigate the effect of Rh doping in Sr₂IrO₄ using X-ray absorption spectroscopy (XAS). We observed appearance of new electron-addition states with increasing Rh concentration (x in Sr₂Ir_1−xRh_xO₄) in accordance with the concept of hole doping. The intensity of the hole-induced state is however weak, suggesting weakness of charge transfer (CT) effect and Mott insulating ground states. Also, Ir J_eff = 1/2 upper Hubbard band shifts to lower energy as x increases up to x = 0.23. Combined with optical spectroscopy, these results suggest a hybridisation-related mechanism, in …

The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2016, Ven Basco

Libraries' Newsletters

No abstract provided.

Increasing 18f-Fdg Pet/Ct Capabilities In Radiotherapy For Lung And Esophageal Cancer Via Image Feature Analysis, Jasmine Alexandria Oliver

USF Tampa Graduate Theses and Dissertations

Positron Emission Tomography (PET) is an imaging modality that has become increasingly beneficial in Radiotherapy by improving treatment planning (1). PET reveals tumor volumes that are not well visualized on computed tomography CT or MRI, recognizes metastatic disease, and assesses radiotherapy treatment (1). It also reveals areas of the tumor that are more radiosensitive allowing for dose painting - a non-homogenous dose treatment across the tumor (1). However, PET is not without limitations. The quantitative unit of PET images, the Standardized Uptake Value (SUV), is affected by many factors such as reconstruction algorithm, patient weight, and tracer uptake time (2). …

Spin-Gapless Semiconductivity And Half Metallicity In Heusler Alloys, Bradley A. Staten, Pavel V. Lukashev

Research in the Capitol

In recent years, ever increasing interest in spin-based electronics (spintronics) has resulted in the search for a new class of materials that can provide a high degree of transport spin polarization. An ideal candidate would act like insulator for one spin channel and a conductor or semiconductor for the opposite spin channel (e.g. half metals (HM), spin gapless semiconductors (SGS)). In this work, we present results of our computational and theoretical study (Staten, et al., J. Appl. Phys. 117, 17D115 (2015)) of Heusler compounds with potential commercial applications in the field of spintronics. We show that naturally these materials are …

Congratulations A-Pin Recipients | College Of Engineering, Usu College Of Engineering

College of Engineering News

March 29, 2016 – Dean Christine Hailey and department heads from across the College of Engineering on Tuesday recognized 13 students for receiving the prestigious A-Pin award.

The A-Pin is one of the oldest awards at Utah State University. Initiated in 1910, it acknowledges and rewards students who achieve a straight-A grade point average while carrying 15 graded credit hours for two consecutive semesters.

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Dr. Mitra Accepts PLTW Award for Georgia

Method To Fabricate Portable Electron Source Based On Nitrogen Incorporated Ultrananocrystalline Diamond (N-Uncd), Anirudha V. Sumant, Ralu Divan, Chrystian M. Posado, Carlos Henry Castano Giraldo, Edwin J. Grant, Hyoung-Koo Lee

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

A source cold cathode field emission array (FEA) source based on ultra-nanocrystalline diamond (UNCD) field emitters. This system was constructed as an alternative for detection of obscured objects and material. Depending on the geometry of the given situation a flat-panel source can be used in tomography, radiography, or tomosynthesis. Furthermore, the unit can be used as a portable electron or X-ray scanner or an integral part of an existing detection system. UNCD field emitters show great field emission output and can be deposited over large areas as the case with carbon nanotube “forest” (CNT) cathodes. Furthermore, UNCDs have better mechanical …