Engineering Commons^™

Esd Current Spread Measurement Using Mesh Structure, Jae-Deok Lim, David Pommerenke, Jong-Sung Lee, Byong-Su Seol

Electrical and Computer Engineering Faculty Research & Creative Works

If a PCB is struck by an ESD the injected current spreads throughout the PCB and returns via attached cables. During the current spread a variety of effects occur: The current spreads on the main ground and power planes, couples into traces and IC lead-frames and bond wires. Further, the PCB and the attached cables can form resonators causing ringing at their natural resonance frequencies. Understanding the current spread onto a PCB, best, also onto the traces is of great importance for gaining insight into ESD related problems on products. A test setup has been created that allows capturing and …

Energy From The Skies: Empowering Future Generations, Petros J. Katsioloudis, Stella Bondi, Walter F. Deal

STEMPS Faculty Publications

The article discusses the development of photovoltaic technology. The first account of the use of solar power during war in western civilization was in the second century B.C. during the battle of Syracuse with Archimedes' famed Death Ray. In the late 1800s and early 1900s many advances occurred including the invention of solar-powered engines, the discovery of the photoconductivity of selenium and its ability to produce electricity when exposed to light, and the construction of the first solar cells from selenium wafers. Photovoltaic technology was born in the U.S. in 1954 when Daryl Chapin, Calvin Fuller, and Gerald Pearson developed …

Performance Related Specifications (Prs) For Concrete Pavements In Indiana, Volume 1: Executive Summary, Cole Graveen, Eric Max Falker, Micah Beaver, Narayanan Neithalath, W. Jason Weiss, J. Olek, Tommy Edward Nantung, Victor Lee Gallivan

JTRP Technical Reports

Performance-Related Specifications (PRS) are specifications that base pavement acceptance and pay adjustment on the projected performance and predicted life-cycle cost (LCC) for a specific pavement. PRS relate measurable quality characteristics with pavement performance through computer simulations that incorporate physical distress models. Previously, work at ERES consultants by Darter and co-workers developed prototype PRS for jointed plain portland cement concrete pavements (PCC) through Federal Highway Administration (FHWA) through a series of research projects. However, before this research program began, pavements have not been constructed using these specifications. This report describes the Indiana Department of Transportation’s (INDOT) experience with developing and implementing …

Performance Related Specifications (Prs) For Concrete Pavements In Indiana, Volume 2: Technical Report, Cole Graveen, Eric Max Falker, Micah Beaver, Narayanan Neithalath, W. Jason Weiss, J. Olek, Tommy Edward Nantung, Victor Lee Gallivan

JTRP Technical Reports

Performance-Related Specifications (PRS) are specifications that base pavement acceptance and pay adjustment on the projected performance and predicted life-cycle cost (LCC) for a specific pavement. PRS relate measurable quality characteristics with pavement performance through computer simulations that incorporate physical distress models. Previously, work at ERES consultants by Darter and co-workers developed prototype PRS for jointed plain portland cement concrete pavements (PCC) through Federal Highway Administration (FHWA) through a series of research projects. However, before this research program began, pavements have not been constructed using these specifications. This report describes the Indiana Department of Transportation’s (INDOT) experience with developing and implementing …

Application Of The Actor-Critic Architecture To Functional Electrical Stimulation Control Of A Human Arm, Philip Thomas, Michael Branicky, Antonie Van Den Bogert, Kathleen Jagodnik

Mechanical Engineering Faculty Publications

Clinical tests have shown that the dynamics of a human arm, controlled using Functional Electrical Stimulation (FES), can vary significantly between and during trials. In this paper, we study the application of the actor-critic architecture, with neural networks for the both the actor and the critic, as a controller that can adapt to these changing dynamics of a human arm. Development and tests were done in simulation using a planar arm model and Hill-based muscle dynamics. We begin by training it using a Proportional Derivative (PD) controller as a supervisor. We then make clinically relevant changes to the dynamics of …

Concurrent Simulation Of Neuromuscular Control And Tissue Deformation Is Possible By Adaptive Surrogate Modeling, Jason P. Halloran, Ahmet Erdemir, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

No abstract provided.

Adaptive Surrogate Modeling For Efficient Coupling Of Musculoskeletal Control And Tissue Deformation Models, Jason P. Halloran, Ahmet Erdemir, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

Background

Finite element (FE) modeling and multibody dynamics have traditionally been applied separately to the domains of tissue mechanics and musculoskeletal movements, respectively. Simultaneous simulation of both domains is needed when interactions between tissue and movement are of interest, but this has remained largely impractical due to high computational cost.

Method of Approach

Here we present a method for concurrent simulation of tissue and movement, in which state of the art methods are used in each domain, and communication occurs via a surrogate modeling system based on locally weighted regression. The surrogate model only performs FE simulations when regression from …

Multiresolution Wavelet Analysis Of The Dynamics Of A Cracked Rotor, Jerzy T. Sawicki, Asok K. Sen, Grzegorz Litak

Mechanical Engineering Faculty Publications

We examine the dynamics of a healthy rotor and a rotor with a transverse crack, which opens and closes due to its self weight. Using discrete wavelet transform, we perform a multiresolution analysis of the measured vibration signal from each of these rotors. In particular, the measured vibration signal is decomposed into eight frequency bands, and the rms amplitude values of the healthy and cracked rotors are compared in the three lowest-frequency bands. The results indicate that the rms vibration amplitudes for the cracked rotor are larger than those of the healthy rotor in each of these three frequency bands. …

Modeling An Instrumented (Tractor-Semitrailer Combination) Vehicle: Using System Identification Methods, Bito Irie

Electrical Engineering Theses - Archive

In this thesis, properties of the input-output relationships of a tractor-semitrailer combination vehicle were analyzed. Predictive models of the system were identified using only input-output data collected separately but for the same portion of the road. A vehicle equipped with an inertial profiling system and a strain gauge instrumented truck were used to collect the input and output data, respectively. Input-output combinations such as single-input-single-output (SISO), multiple-input-single-output (MISO), and multiple-input-multiple-output (MIMO) representing the vehicle models were investigated using the polynomial and state-space black-box modeling (i.e., system identification) techniques. Comparisons among measured and k-steps ahead predicted outputs and residual analysis were …

Electrical Detection Of Single-Based Dna Mutation Using Functionalized Nanoparticles, Mohammud R. Noor

Electrical Engineering Theses - Archive

DNA molecules posses unique structure and molecular recognition properties that makes them excellent candidate for bio-chemical sensors. Understanding the mechanism of charge transport in DNA is essential to develop DNA based molecular electronic devices. In the experiment reported in this thesis, we analyzed an electrical method to detect specific DNA. Hairpin probe DNA was engineered to melt and hybridize with certain perfect complementary sequences and immobilized on a silicon chip between gold nanoelectrodes. Hybridization of target DNA to the hairpin melts or open up the stem nucleotides, which provides DNA hybridization sites. Gold nanoparticle-conjugated universal reporter sequence detects the open …

Signal Processing In Radar And Non-Radar Sensor Networks, Jing Liang

Electrical Engineering Dissertations - Archive

This dissertation studies six topics within the area of radar andnon-radar sensor networks from a signal processing perspective:radar sensor networks (RSN) waveform design and performance analysis(chapter 2), blind speed alleviation using RSN (chapter 3), targetdetection in foliage using Ultra-Wideband (UWB) RSN (chapter 4),sense-through-foliage\&wall channel modeling (chapter 5), channelselection algorithms in virtual multiple-input-multiple-output(MIMO) sensor networks (chapter 6) and RF emitter passivegeolocation using unmanned aerial vehicles (UAVs) and sensors(chapter 7).In RSN, distributed radar sensors work in an ad hoc fashion but aregrouped together by an intelligent clusterhead that combineswaveform diversity. RSN not only provide spatial resilience fortarget detection and tracking compared to …

Independent Source Extraction Applied To Radar Imaging, Jeffrey Brandon Hall

Electrical Engineering Theses - Archive

Multiple scattering and random interactions among scattering elements and between the scatterers and the background adversely affect the radar image quality and target detection capability. In radar images formed using physical optics (PO) based techniques, multiple scattering and interactions appear as non-physical scattering centers. A method to enhance the performance of PO based radar imaging systems by extracting independent scattering centers is investigated in this thesis. Independent Component Analysis (ICA) is applied to returns of a radar system to extract independent scattering elements based on their non-Gaussianity. As an example, this method of target extraction is implemented in inverse synthetic …

Modeling And Simulation Of The Flight Dynamics Of Morphing Wing Aircraft, Borna Obradovic

Mechanical and Aerospace Engineering Theses - Archive

Aircraft with variable wing geometry (morphable wings) are of considerable interest, not only for mission-specific optimization, but for enhanced maneuverability as well. In the nascent field of mini- or micro-Unmanned Aerial Vehicles (UAVs), large and rapid changes in wing geometry are achievable, resulting in significant changes of the dynamics of the vehicle. In this thesis, we present a simulation methodology suitable for such aircraft, accounting for the changes in both the aerodynamic and inertial properties. Due to the complexity of the possible wing configurations, the aerodynamics are simulated using an unsteady Vortex-Lattice approach, solved concurrently with six(+) degrees of freedom …

New Model Of Productive Online Discussion And Its Implications For Research And Instruction, Fei Gao, Charles Xiaoxue Wang, Yanling Sun

Visual Communications and Technology Education Faculty Publications

We develop a new model of productive online discussion based on a brief review of research literature on online discussion. As compared to previous discussion models, the new model provides a more systematic and comprehensive framework to understand how learning occurs through online discussion. Based on the new model, we propose several directions for research on improving the quality of online discussion and learning.

Direct Numerical Simulation Of Interaction Of Detonation Wave With Homogeneous Isotropic Turbulence, Hari Narayanan Nagarajan

Mechanical and Aerospace Engineering Theses - Archive

The propagation of a shock or detonation wave through a reactive mixture has been the subject of research for over a century. The basic understanding has been shaped by one-dimensional Euler models, namely, those of Chapman-Jouguet and Zeldovich-Neumann-Doring, despite the fact that the detonation front is multidimensional. Other complications include observations of detonation instability, and spinning and galloping detonations. Recent advances in CFD have made it possible to examine detonation waves in great detail. These studies have revealed the complex nature of detonations that were observed experimentally. Some outstanding issues include the influence of inhomogeneities in the reactive mixture on …

Thermo-Mechanical Interaction Within Engineered Tissue During Freezing, Tenok Dehoyos

Mechanical and Aerospace Engineering Theses - Archive

Cryopreservation is the preserving of biological tissues at sub zero temperature. There are many useful applications to cryopreservation such as storing donated organs till they are needed rather than letting them go to waste. When tissues are frozen and thawed, their original functionality and vitality are not usually maintained. It's been shown that when tissue is frozen its mechanical properties change, such as tensile strength and modulus. Each tissue has an extra cellular matrix made up of many collagen fibrils that is responsible for the structural integrity of the tissue. This study is to investigate the structural changes of ECM …

Applications Of Gis For Mapping And Tracking Underground Infrastructure, Anurag Babu Bhogenahally Lakshminarayanappa

Civil Engineering Theses - Archive

The main objective of this research is to apply Geographic Information Systems (GIS) for construction and renewal of underground infrastructures. As a first step, a suitability analysis to determine location of existing underground infrastructure is performed. Next, a GIS template is developed using a digital elevation model (DEM) to get a three dimensional visualization of the underground infrastructure. Creating a Google Map using ArcGIS is one of the key features of this research, which provides an exact location of the existing site and distances from the nearby reference points. Once the GIS data is exported to Google Map and Google …

Long Term Durability Studies On Chemically Treated Reclaimed Asphalt Pavement (Rap) Materials, Vijay Krishna Ganne

Civil Engineering Theses - Archive

Reclaimed Asphalt Pavement (RAP) is a well known construction material which has been used in Hot Mix Asphalt (HMA) to reduce material costs and stabilizing the pavements for several years. It has been reported that out of 45 million tons of RAP produced every year in US, only 33% is being used in HMA. It is clear that a large amount of RAP produced is disposed off as a waste material in landfills. Hence, in order to utilize the maximum percentage of RAP and reduce the disposal rate, stabilized RAP can be effectively used as a base layer instead of …

Nepa And The Dynamics Of Public Participation In The Environmental Review Process: An Analysis Of The Northmet (Polymet) Mining Project Near Hoyt Lakes Minnesota, Amber Neumann

Political Science Theses and Capstones

Hypothesis: That comments collected from agency “experts” during the scoping phase of the National Environmental Policy Act (NEPA) process would be disproportionately represented as changes in subsequent drafts of NorthMet’s Environmental Impact Statement (EIS).

Methods: Tabular analysis of data collected from the Minnesota DNR publication of Response to the Public Scoping Projects PolyMet Mining Inc.; NorthMet Project. 2005

Results: There is an excellent cross section of comment sources represented in changes to subsequent drafts of NorthMet’s EIS. A lot of overlap exists between various types of participants and their concerns, resulting in many of the successful comments stemming from …

Modeling Of The Interior Electric Field In Photovoltaic Cells, Tara Jeatran

The Journal of Undergraduate Research

With the emergence of photovoltaic technologies, there is a strong technological demand for high-performance photovoltaic devices. One of the most promising device concepts developed at SDSU is organic-based photovoltaic cells. The performance of the PV cells is controlled by charge generation and charge separation, and charge transportation processes. Extraordinary control over the properties of the organic photovoltaic materials will be needed in order for this research to succeed. Therefore, the interior electric field and the macro electric properties of the system are the foundation behind these facts and are critical properties on their performance. In this paper, the fundamentals of …

Reduction Of Model Order Based On Proper Orthogonal Decomposition For Lithium-Ion Battery Simulations, Long Cai, Ralph E. White

Faculty Publications

A reduced-order model (ROM) is developed using proper orthogonal decomposition (POD) for a physics-based lithium-ion battery model. The methodology to obtain the proper orthogonal modes and to analyze their optimality is included. The POD-based ROM for a lithium-ion battery is used to simulate a charge/discharge process and the behavior of a battery pack. Compared to the physics-based model, the computational time to solve the ROM is significantly less, and the two models show excellent agreement.

Effect Of Water Transport On The Production Of Hydrogen And Sulfuric Acid In A Pem Electrolyzer, John A. Staser, John W. Weidner

Faculty Publications

The thermochemical cycle involving the interconversion between sulfur dioxide and sulfuric acid is a promising method for efficient, large-scale production of hydrogen. A key step in the process is the oxidation of sulfur dioxide to sulfuric acid in an electrolyzer. Gaseous SO₂ fed to a proton exchange membrane (PEM) electrolyzer was previously investigated and was shown to be a promising system for the electrolysis step. A critical factor in the performance of this gas-fed electrolyzer is the management of water since it: (i) is needed as a reactant, (ii) determines the product sulfuric acid concentration, …

Electrochemical Removal Of Carbon Monoxide In Reformate Hydrogen For Fueling Proton Exchange Membrane Fuel Cells, Sivagaminathan Balasubramanian, Charles E. Holland, John W. Weidner

Faculty Publications

A twin-cell electrochemical filter is demonstrated to reduce the CO concentration in reformate hydrogen. In this design, the potential and gas flow are switched between the two filter cells so that alternative CO adsorption and oxidation occur in each cell while providing a continuous flow of H2 to a fuel cell. The effects of filter switching time and applied potential on the CO concentration of gas exiting the filter are presented here for a CO concentration of 1000 ppm in nitrogen flowing at 100 cm3/min. The parasitic loss of hydrogen from a corresponding reformate stream was estimated to be 1.5%.

Tunable Laser Interrogation Of Surface Plasmon Resonance Sensors, Vaibhav Badjatya

University of Kentucky Master's Theses

Surface plasmons are bound TM polarized electromagnetic waves that propagate along the interface of two materials with real dielectric constants of opposite signs. Surface plasmon resonance (SPR) sensors make use of the surface plasmon waves to detect refractive index changes occurring near this interface. For sensing purposes, this interface typically consists of a metal layer, usually gold or silver, and a liquid dielectric. SPR sensors usually measure the shift in resonance wavelength or resonance angle due to index changes adjacent to the metal layer. However this restricts the limit of detection (LOD), as the regions of low slope (intensity vs. …

Joint Visual And Wireless Tracking System, Viswajith Karapoondi Nott

University of Kentucky Master's Theses

Object tracking is an important component in many applications including surveillance, manufacturing, inventory tracking, etc. The most common approach is to combine a surveillance camera with an appearance-based visual tracking algorithm. While this approach can provide high tracking accuracy, the tracker can easily diverge in environments where there are much occlusions. In recent years, wireless tracking systems based on different frequency ranges are becoming more popular. While systems using ultra-wideband frequencies suffer similar problems as visual systems, there are systems that use frequencies as low as in those in the AM band to circumvent the problems of obstacles, and exploit …

Direct Electron-Beam Patterning Of Teflon-Af And Its Application To Optical Waveguiding, Vijayasree Karre

University of Kentucky Master's Theses

Thin films of Teflon AF have been directly patterned by electron-beam lithography without the need for post exposure chemical development. The relationship between pattern depth and exposure dose was found to be linear over a wide range of doses. Pattern depth was also observed to be dependent on initial film thickness. Teflon AF can be directly patterned at doses similar to typical e-beam resists. High resolution features as small as ~200 nm have been resolved. FTIR measurements revealed that CF3 and fluorinated dioxole groups play a significant role in the patterning mechanism. Teflon AF films also exhibited an increase in …

The Effectiveness Of Asynchronous Podcasting Of Classes, John Chen

Mechanical Engineering

In this study we examine in some detail the effectiveness of enhanced podcasting compared with traditional face-to-face class meeting. Enhanced podcasting goes beyond simply recording the audio portion of a lecture. It may include the video footage from the class meeting or, as in our case, the presented material (including each written pen stroke) exactly as seen by students sitting in the classroom with the instructor. The course we studied is Applied Thermodynamics, a junior-level course for mechanical engineering students. For this study we had access to three sections of the course, all taught by the same faculty member. For …

Urban Transportation Planning Decision Making: A Robustness Analysis Approach, Deogratias Eustace

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Travel demand modeling remains a cornerstone of the transportation planning process. Although current transportation planning procedures are mostly performed by an interdisciplinary team approach, there are still a number of institutional issues which may hinder the process from providing the best results. According to Marshment (2001), the most notable setback is a lack of coordination between land use and transportation planning. Most of the time, land use plans do not reflect the influence of the accessibility to the alternative transportation facilities.

The lack of interaction between land use and transportation planning may play a major role in using unrealistic and …

Contextualizing Observational Data For Modeling Human Performance, Viet Trinh

Electronic Theses and Dissertations

This research focuses on the ability to contextualize observed human behaviors in efforts to automate the process of tactical human performance modeling through learning from observations. This effort to contextualize human behavior is aimed at minimizing the role and involvement of the knowledge engineers required in building intelligent Context-based Reasoning (CxBR) agents. More specifically, the goal is to automatically discover the context in which a human actor is situated when performing a mission to facilitate the learning of such CxBR models. This research is derived from the contextualization problem left behind in Fernlund's research on using the Genetic Context Learner …

Effect Of Sodium And Absorber Thickness On Cigs2 Thin Film Solar Cells, Parag Vasekar

Electronic Theses and Dissertations

Chalcopyrites are important contenders among solar cell technologies due to direct band gap and higher absorption coefficient. CuIn1-xGaxS2 (CIGS2) thin-film solar cells are of interest for space power applications because of near optimum bandgap of 1.5 eV for AM0 solar radiation outside the earth's atmosphere. The record efficiency of 11.99% has been achieved on a 2.7 µm CIGS2 thin film prepared by sulfurization at FSEC PV Materials Laboratory. Since CIGS2 films are typically grown in copper-rich regime, excess cuprous sulfide which helps in the formation of CIGS2 is etched away. This makes CIGS2 nearly stoichiometric. However, it is difficult to …