Engineering Commons^™

A Visual Return-To-Home System For Gps-Denied Flight, Benjamin Paul Lewis

Theses and Dissertations

Unmanned aerial vehicle technology is rapidly maturing. In recent years, the sight of hobbyist aircraft has become more common. Corporations and governments are also interested in using drone aircraft for applications such as package delivery, surveillance and communications. These autonomous UAV technologies demand robust systems that perform under any circumstances. Many UAV applications rely on GPS to obtain information about their location and velocity. However, the GPS system has known vulnerabilities, including environmental signal degradation, terrestrial or solar weather, or malicious attacks such as GPS spoofing. These conditions occur with enough frequency to cause concern. Without a GPS signal, the …

Stability Of The M2 Phase Of Vanadium Dioxide Induced By Coherent Epitaxial Strain, N. F. Quackenbush, Yijia Gu, For Full List Of Authors, See Publisher's Website.

Materials Science and Engineering Faculty Research & Creative Works

Tensile strain along the cR axis in epitaxial VO₂ films raises the temperature of the metal insulator transition and is expected to stabilize the intermediate monoclinic M2 phase. We employ surface-sensitive x-ray spectroscopy to distinguish from the TiO₂ substrate and identify the phases of VO₂ as a function of temperature in epitaxial VO₂/TiO₂ thin films with well-defined biaxial strain. Although qualitatively similar to our Landau-Ginzburg theory predicted phase diagrams, the M2 phase is stabilized by nearly an order of magnitude more strain than expected for the measured temperature window. Our results reveal that the …

Preface To The Special Issue On Advanced Microstructural Characterization Of Materials, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Microstructural characterization is a vital part in materials science, as it plays a key role in understanding the structure-property relationship in materials. Various advanced microstructural characterization techniques have emerged, for example, scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, high resolution (scanning) transmission electron microscopy, electron backscatter diffraction, energy dispersive x-ray spectroscopy, electron energy loss spectroscopy, precession electron diffraction, energy-filtered transmission electron microscopy, and atom probe tomography. The applications of these techniques have greatly advanced the understanding of material microstructures on different scales from micrometer to atomic scale. Advanced microstructural characterization can be applied to a variety of …

A Fast Filtering Block-Sparse Proportionate Affine Projection Sign Algorithm, Felix Albu, Jianming Liu, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new proportionate affine projection sign algorithm for block-sparse identification using a fast recursive filtering procedure and dichotomous coordinate descent iterations is proposed. It is shown that the proposed algorithm is a good candidate for network echo cancellation systems operating under impulsive environments.

Free Deterministic Equivalents For The Analysis Of Mimo Multiple Access Channel, An An Lu, Xiqi Gao, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a free deterministic equivalent is proposed for the capacity analysis of the multi-input multi-output (MIMO) multiple access channel (MAC) with a more general channel model compared to previous works. In particular, a MIMO MAC with one base station (BS) equipped with several distributed antenna sets is considered. Each link between a user and a BS antenna set forms a jointly correlated Rician fading channel. The analysis is based on operator-valued free probability theory, which broadens the range of applicability of free probability techniques tremendously. By replacing independent Gaussian random matrices with operator-valued random variables satisfying certain operator-valued …

Laboratory Characterization Of Ohio Gold Frac Sand, Maria Gabriela Alvarado Calle

Open Access Theses

The mechanical response of sand depends on state variables (such as density, stress state and fabric) and intrinsic variables (such as particle size distribution and particle shape). The mechanical response of sand is also a function of sand crushability. Recent research studying the cone penetration process in a unique digital image correlation (DIC) chamber is underway at Purdue University. The test sand is Ohio Gold Frac sand, which meets criteria regarding particle size and gradation related to elimination of chamber boundary and scale effects.

The mechanical behavior of this sand can be simulated by a suitable constitutive model, such as …

Role Of River Bathymetry In Hydraulic Modeling Of River Channels, Sayan Dey

Open Access Theses

Accurate geometric representation of the river channel is required for accurate hydraulic modeling of rivers. These are generally obtained through remote sensing techniques such as Light Detection and Ranging (LIDAR). However, these techniques lack the ability to model the submerged channel bed effectively and need to be complemented with surveyed bathymetric data for complete representation of the channel bathymetry, which can be time and cost prohibitive. An alternative to address this issue is to develop conceptual models that can estimate bathymetry.

This study aims to evaluate the potential of a conceptual model, the River Channel Morphology Model (RCMM) which estimates …

Modeling The Impact Of Battery Degradation Within Lifecycle Cost Based Design Optimization Of Heavy-Duty Hybrid Electric Vehicles, Ashish P. Vora

Open Access Dissertations

The optimal design of hybrid electric vehicle (HEV) powertrains from a systems perspective is critical to realize the maximum benefits for a given application. This is particularly true in the heavy-duty vehicle space where the major challenges are: (i) greater emphasis on economic viability, (ii) reluctance to take on risk associated with new technologies, and (iii) numerous diverse applications that preclude a one-size-fits-all approach to hybrid-electric powertrain design. Past studies on HEV powertrain design have either ignored battery degradation, or failed to holistically capture its impact from a lifecycle cost perspective. The focus of this effort is the development of …

Fuel Type Estimation Using Fuel System Parameters, Shambhavi Balasubramanian

Open Access Theses

A number of factors are responsible for an increased interest in alternative fuels for transportation and other uses. Among the most widely available alternative fuels are biodiesel and vegetable oil, both of which can be used to power a diesel engine. Biodiesel has higher density, viscosity, surface tension, sound velocity, and bulk modulus of elasticity than regular diesel fuel. This affects the fuelling, injection timing, and fuel spray and consequently the emission characteristics.

Estimation of fuel type is critical to the performance of the engine. Knowing the fuel type allows the engine controller to determine the proper fuel quantity and …

Roundabout Maintenance Flipbook, Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

This flipbook is a summary of the work published in the Roundabout Maintenance Manual by Indiana LTAP. This information was collected through a series of interviews with city engineers, public works directors, and street commissioners experienced in roundabout maintenance. It serves as a model to guide work crews in correct maintenance procedures.

Roundabout Maintenance Manual, Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

This maintenance manual serves as an additional resource for communities who have imple­mented roundabouts or are considering them. There are a few other published guides, such as the NCHRP Report 672, Roundabouts: An Informational Guide, and the Wisconsin DOT Facilities Develop­ment Manual. However, the information covered in these guides is very broad. This manual provides specific information regarding roundabout maintenance.

Review Of Fluorescence Guided Surgery Systems: Identification Of Key Performance Capabilities Beyond Indocyanine Green Imaging, Alisha V. Dsouza, Huiyun Lin, Eric R. Henderson, Kimberley S. Samkoe

Dartmouth Scholarship

There is growing interest in using fluorescence imaging instruments to guide surgery, and the leading options for open-field imaging are reviewed here. While the clinical fluorescence-guided surgery (FGS) field has been focused predominantly on indocyanine green (ICG) imaging, there is accelerated development of more specific molecular tracers. These agents should help advance new indications for which FGS presents a paradigm shift in how molecular information is provided for resection decisions. There has been a steady growth in commercially marketed FGS systems, each with their own differentiated performance characteristics and specifications. A set of desirable criteria is presented to guide the …

Gamma-Radiation Exposure Alters The Cardiovascular Extracellular Matrix., Nicholas Allen

Electronic Theses and Dissertations

Ionizing radiation has been associated with various cardiovascular complications; however, the associated molecular changes from radiation exposure still remain largely uncharacterized. Alterations to the cardiovascular tissue microenvironment, i.e. the extracellular matrix (ECM), directly affect the function of integrated vascular cells, including cell adhesion, potential to form vessels, and endothelial permeability, which can promote cardiovascular pathologies. The ECM is constantly remodeled in response to stimuli, such as TGF-β1, which leads to excessive ECM accumulation. We hypothesize that radiation exposure will alter the cardiovascular ECM. Human Cardiac Fibroblasts (HCFs) were utilized to produce ECM as an in vitro model to study changes …

Solution Of Fully-Coupled Shallow Water Equations And Contaminant Transport Using A Primitive Variable Riemann Solver And A Semi-Discrete Supg Method, Faranak Behzadi

Masters Theses and Doctoral Dissertations

In the present dissertation, a finite volume and a finite element model are developed and tuned for the solution of the fully-coupled two-dimensional Shallow Water and Contaminant transport Equations with arbitrary bed topography and wetting-drying fronts. A Riemann-solver finite volume scheme, using primitive variables rather than conserved variables, and a semi-discrete Streamline Upwind Petrov-Galerkin (SUPG) method in finite element context are applied to compare the performance of these two numerical models. The Riemann-solver scheme is based on the unstructured finite volume discretization using primitive-variable Roe-flux approximation with an entropy fix. Second-order accuracy in space and time, an implicit scheme based …

Least Squares Spectral Element Method For Laminar And Turbulent Flows, –Continuous And Discontinuous Approaches–, Jaber Javanshir Hasbestan

Masters Theses and Doctoral Dissertations

In this research, application of a least squares spectral element method for compressible laminar and turbulent flow problems is investigated. For the turbulent Reynolds Averaged Navier-Stokes (RANS), a modified Spalart-Allmaras (SA) turbulence model is employed and integrated with the mean flow equations in a segregated fashion. Two different approaches are presented for solving the SA model using the least squares method. The first method represents a simple rearrangement of the equation. However, proper arrangement of the SAmodel is required in order to produce a stable scheme for the least squares methodology. The second approach is into divide the SA equation …

Active Fault Tolerant Control For Vertical Tail Damaged Aircraft With Dissimilar Redundant Actuation System, Wang Jun, Wang Shaoping, Wang Xingjian, Shi Cun, Mileta M. Tomovic

Engineering Technology Faculty Publications

This paper proposes an active fault-tolerant control strategy for an aircraft with dissimilar redundant actuation system (DRAS) that has suffered from vertical tail damage. A damage degree coefficient based on the effective vertical tail area is introduced to parameterize the damaged flight dynamic model. The nonlinear relationship between the damage degree coefficient and the corresponding stability derivatives is considered. Furthermore, the performance degradation of new input channel with electro-hydrostatic actuator (EHA) is also taken into account in the damaged flight dynamic model. Based on the accurate damaged flight dynamic model, a composite method of linear quadratic regulator (LQR) integrating model …

A Transcutaneous Data And Power Transfer System For Osteogenesis Monitoring Sensors, Deepak Dileepkumar

Masters Theses

Implant devices are widely used in health care applications such as life support systems, patient rehabilitation devices and patient monitoring devices. Medical implants have enabled physicians to obtain relevant real time information regarding an organ, or a site of interest with in the body and suggest treatment accordingly. In some cases, the position of the implant within the body or threats of infections prevents wired communication techniques to extract information from the implant. Wireless communication is the alternative in such cases. Distraction osteogenesis is one such application where wireless communication can be established with callus growth monitoring sensors to obtain …

Framework For Incorporating Probabilistic Building Performance In The Assessment Of Community Seismic Resilience, Henry V. Burton, Gregory Deierlein, David Lallemant, Ting Lin

Civil and Environmental Engineering Faculty Research and Publications

A framework is presented for incorporating probabilistic building performance limit states in the assessment of community resilience to earthquakes. The limit states are defined on the basis of their implications to postearthquake functionality and recovery. They include damage triggering inspection, occupiable damage with loss of functionality, unoccupiable damage, irreparable damage, and collapse. Fragility curves are developed linking earthquake ground motion intensity to the probability of exceedance for each of the limit states. A characteristic recovery path is defined for each limit state on the basis of discrete functioning states, the time spent within each state, and the level of functionality …

Rare Earth Emissions From Polyethylene Terephthalate Fiber, Joshua Jenkins Furtick

All Theses

Rare earth-polymer blends can be useful in many applications including safety, security, displays, and novelty. Polyester, specifically polyethylene terephthalate, is a ubiquitous material in the world today and offers many opportunities for the usefulness of visible light rare earth emissions.

In this work we have attempted to incorporate rare earth complexes with polyester yarn using various methods including coating, extrusion, and dyeing, with the latter having the most success. Nanoparticles were used initially for these experiments, however certain limitations of the particles could not be overcome, for example the size of the particles and the incompatibility of the inorganic matrix …

Autologous Protein Solution Exhibits Potential To Mitigate Osteoarthritis (Oa) Progression In A Human Explant Co-Culture Model, Kathleen Emily Steckbeck

All Theses

Osteoarthritis (OA) is a debilitating and painful disease that affects upwards of one in every eight adults1,2. OA influences the entire joint, but is traditionally characterized by cartilage degradation3. OA is a multifactorial disease with genetic, biological, and biochemical consideration, but there has been a recent shift in scientific opinion that the pathological progression of OA stems from an inflammatory milieu produced by the feed-forward progressive pathway as evidenced by simultaneous cartilage and synovium co-culture4–7. Autologous protein solution (APS) poses as an intriguing potential OA therapy by possessing a high anti-inflammatory and anabolic mediator concentration profile that could potentially mitigate …

Enhanced Thermal Conductance Of Polymer Composites Through Embedding Aligned Carbon Nanofibers, David S. Wood, Dale K. Hensley, Nicholas A. Roberts

Mechanical and Aerospace Engineering Faculty Publications

The focus of this work is to find a more efficient method of enhancing the thermal conduc-tance of polymer thin films. This work compares polymer thin films embedded with randomly oriented carbon nanotubes to those with vertically aligned carbon nanofibers. Thin films embedded with carbon nanofibers demonstrated a similar thermal conductance between 40–60 µm and a higher thermal con-ductance between 25–40 µm than films embedded with carbon nanotubes with similar volume fractions even though carbon nanotubes have a higher thermal conductivity than carbon nanofibers.

Repair Severed Nerve Connections Through A Multi-Branch Microchannel Scaffold To Control The Direction Of The Regenerated Nerve, Luis Enrique Castanuela Ramon

Theses and Dissertations

Damage to the peripheral nervous system may result in functional abnormalities due to disrupted nerve connections. Existing methods of repairing severed nerve connections in the peripheral nervous system have limitations and disadvantages such as a limited availability of donor nerves and a lack of control of the direction of nerve regeneration within nerve conduits. A handcrafted multi-branch microchannel scaffold improves upon the current methods of nerve repair by incorporating microchannels, which guide and accommodate the nerve regeneration to distal ends, allowing for the treatment of nerve injuries involving multiple branches with fewer surgeries. This scaffold is also made more accessible …

Biocompatible Microchannel Scaffold With Microwires For Recording Regenerative Peripheral Nerve Neural Spikes, Manisankar Chennamsetti

Theses and Dissertations

A new process for the fabrication of a microchannel scaffold with microwires for peripheral nerve applications is presented. This microchannel scaffold implemented between the ends of nerves, the axons of which regenerate through microchannel in scaffold and fixed microelectrodes. This device is entirely handcrafted using commercially available materials such as microwires, PDMS film, liquid PDMS, dental cement, and epoxy glue. This device was implemented in the a Lewis rat sciatic nerve to better analyze the electrical signals of regenerated axons. 64-electrode microchannel scaffolds were developed for both peripheral nerve interfacing and peripheral nerve regeneration. The microwires were used for recording …

Detecting Delamination In Carbon Fiber Composites Using Piezoresistive Nanocomposites, Sandeep Chava

Doctoral Dissertations and Master's Theses

Carbon fiber prepreg composites are utilized successfully as structural materials for different lightweight aerospace applications. Delamination is a critical failure mode in these composite materials. As composite plies separate from each other, the composite loses some of its ability for supporting expected loads. Therefore, detection of delamination at right time is a foremost significance. This study presents a new way for detecting delamination in composite plates using piezoresistive nanocomposites. This new procedure is setup and studied through both experimental and computational investigations. In this research, nanocomposites with 5% coarse graphene platelets are fabricated for detecting delamination. 8-ply carbon fiber prepreg …

Vision-Aided Navigation For Autonomous Vehicles Using Tracked Feature Points, Ahmed Saber Soliman Sayem

Doctoral Dissertations and Master's Theses

This thesis discusses the evaluation, implementation, and testing of several navigation algorithms and feature extraction algorithms using an inertial measurement unit (IMU) and an image capture device (camera) mounted on a ground robot and a quadrotor UAV. The vision-aided navigation algorithms are implemented on data-collected from sensors on an unmanned ground vehicle and a quadrotor, and the results are validated by comparison with GPS data. The thesis investigates sensor fusion techniques for integrating measured IMU data with information extracted from image processing algorithms in order to provide accurate vehicle state estimation. This image-based information takes the forms of features, such …

A Novel Particle Filtering Method For Estimation Of Pulse Pressure Variation During Spontaneous Breathing, Sunghan Kim, Fouzia Noor, Mateo Aboy, James Mcnames

Electrical and Computer Engineering Faculty Publications and Presentations

Background: We describe the first automatic algorithm designed to estimate the pulse pressure variation ([Formula: see text]) from arterial blood pressure (ABP) signals under spontaneous breathing conditions. While currently there are a few publicly available algorithms to automatically estimate [Formula: see text] accurately and reliably in mechanically ventilated subjects, at the moment there is no automatic algorithm for estimating [Formula: see text] on spontaneously breathing subjects. The algorithm utilizes our recently developed sequential Monte Carlo method (SMCM), which is called a maximum a-posteriori adaptive marginalized particle filter (MAM-PF). We report the performance assessment results of the proposed algorithm on …

Profit Based Simulation Model For The Rail Transportation Industry, Mark Patrick Doran

Engineering Management & Systems Engineering Theses & Dissertations

Schedules often conflict in the rail transportation industry. Operations managers assign resources and make scheduling decisions with no visibility of the revenue, cost, and profitability characteristics of the route they are manipulating. Transit speed decisions focus on ensuring trains safely reach their destination on time with little regard given to the actual service needs of the customer. Although all customers want on-time deliveries, few actually pay a premium to garner this level of preferential treatment. Operating in this type of environment results in decisions that severely erode profits.

In this dissertation, a simulation model referred to as the Rail Profit …

Visualizations Of Travel Time Performance Based On Vehicle Re-Identification Data, Stanley E. Young, Elham Sharifi, Christopher M. Day, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

This paper provides a visual reference of the breadth of arterial performance phenomena based on travel time measures obtained from reidentification technology that has proliferated in the past 5 years. These graphical performance measures are revealed through overlay charts and statistical distribution as revealed through cumulative frequency diagrams (CFDs). With overlays of vehicle travel times from multiple days, dominant traffic patterns over a 24-h period are reinforced and reveal the traffic behavior induced primarily by the operation of traffic control at signalized intersections. A cumulative distribution function in the statistical literature provides a method for comparing traffic patterns from various …

Study Design Of A Cluster-Randomized Controlled Trial To Evaluate A Large-Scale Distribution Of Cook Stoves And Water Filters In Western Province, Rwanda, Corey L. Nagel, Miles Kirby, Laura D. Zambrano, Ghislaine Rosa, Christina K. Barstow, Evan A. Thomas, Thomas Clasen

Mechanical and Materials Engineering Faculty Publications and Presentations

Background: In Rwanda, pneumonia and diarrhea are the first and second leading causes of death, respectively, among children under five. Household air pollution (HAP) resultant from cooking indoors with biomass fuels on traditional stoves is a significant risk factor for pneumonia, while consumption of contaminated drinking water is a primary cause of diarrheal disease. To date, there have been no largescale effectiveness trials of programmatic efforts to provide either improved cookstoves or household water filters at scale in a low-income country. In this paper we describe the design of a clusterrandomized trial to evaluate the impact of a national-level program …

A Distributed Processing Platform With Reconfigurable Autonomous Nodes, Grzegorz Chmaj

UNLV Theses, Dissertations, Professional Papers, and Capstones

Distributed processing is a fast growing area of interest due to the exploding popularity of Internet of Things (IoT) and Unmanned Aerial Vehicles (UAV) technologies. IoT is a distributed processing structure by nature, while UAVs evolve from single-UAV applications towards multiple-UAV (teams). The demand for processing capabilities is expanding as well. The general purpose processors (e.g. CPUs) can be used for any type of application, however this flexibility is at the cost of operational efficiency. Application Specific Integrated Circuits (ASICs) are designed for certain types of application and have great operational efficiency, but they rarely can be used for other …