Engineering Commons^™

An Assessment Of Delivery Risks In Transportation Projects, Velvet Fitzpatrick, Kumares C. Sinha

JTRP Technical Reports

A large number of uncertainties exist in the delivery of highway projects, and it is important to describe the extent so that budgeting and programming can be carried out in a manner that duly accounts for such uncertainties. The study investigates the sources of delivery variability (risk factors) that occur in the period between project proposed date and the letting date. Data on 366 highway projects were collected from the Indiana Department of Transportation Management Information Portal. Using statistical and econometric techniques, the data was analyzed to identify the potential risk factors and to determine the magnitude and direction of …

Impaired Vascular Reactivity Following Chronic Ischemia In The Arteries Of The Mouse Hindlimb, Thomas (Tom) Kesler

Biomedical Engineering

Collateral dependent hyperemia is reduced following chronic ischemia, but the contribution of individual vessel reactivity is unknown. Further, it is not known what aspect of the complex ischemic injury response impacts vascular reactivity. To determine the impact of ischemia on vascular reactivity, we measured functional vasodilation in the muscular branch artery following resection of the femoral artery proximal to the muscular branch. On day-14 after surgery the diameter of the muscular branch was measured using side-stream dark field (SDF) imaging intravital microscopy. At moderate intensity skeletal muscle contraction (1mA, 200µs, 8Hz, 90sec), functional vasodilation is reduced compared to the contralateral …

Morphological Assessment Of Basic Multicellular Unit Resorption Parameters In Dogs Shows Additional Mechanisms Of Bisphosphonate Effects On Bone, Matthew R. Allen, Antonia M. Erickson, Xiang Wang, David B. Burr, R. Bruce Martin, Scott J. Hazelwood

Biomedical Engineering

Bisphosphonates (BPs) slow bone loss by reducing initiation of new basic multicellular units (BMUs). Whether or not BPs simply prevent osteoclasts from initiating new BMUs that resorb bone or also reduce the amount of bone they resorb at the BMU level is not clear. The goal of this study was to determine the effects of BPs on three morphological parameters of individual BMUs, resorption depth (Rs.De), area (Rs.Ar), and width (Rs.Wi). After 1 year of treatment with vehicle (VEH), alendronate (ALN; 0.10, 0.20, or 1.00 mg/kg/day), or risedronate (RIS; 0.05, 0.10, or 0.50 mg/kg/day), resorption cavity morphology was assessed in …

Impaired Vascular Reactivity Following Chronic Ischemia In The Arteries Of The Mouse Hindlimb, Trevor Cardinal, Thomas J. Kesler, Matthew D. Yocum, Tyler S. Smith, Nolan M. Mott

Biomedical Engineering

No abstract provided.

Forty Years Of Movie Hacking: Considering The Potential Implications Of The Popular Media Representation Of Computer Hackers From 1968 To 2008, Damian Gordon

Articles

Increasingly movies are being produced which feature plots that incorporate elements of computer security and hacking, and cumulatively these movies are creating a public perception as to the nature of computer security. This research examines movies that feature hackers (and hacking) to identify if any common themes emerge from these movies in their representation of these issues. To achieve this, first a corpus of hacking movies is created, and then using a qualitative data analysis technique, guidelines are developed which distinguish those movies that actually have the potential to create a perception with the general public. The resultant dataset is …

Defending Privacy: The Development And Deployment Of A Darknet, Conor Mcmanamon, Fredrick Mtenzi

Conference papers

New measures imposed by governments, Internet service providers and other third parties which threaten the state of privacy are also opening new avenues to protecting it. The unwarranted scrutiny of legitimate services such as file hosters and the BitTorrent protocol, once relatively unknown to the casual Internet user, is becoming more obvious. The darknet is a rising contender against these new measures and will preserve the default right to privacy of Internet users. A darknet is defined in the context of file sharing as a network which operates on top of another network such as the Internet for the purpose …

Helmsman, Set A Course : Using A Compass And Rfid Tags For Indoor Localisation And Navigation, Yan Li, Brian Mac Namee, John D. Kelleher

Conference papers

Localisation and navigation are still two of the most important issues in mobile robotics. In certain indoor application scenarios RFID (radio frequency identification)-based absolute localisation has been found to be especially successful in supporting navigation. In this paper we evaluate the feasibility of an RFID and compass based approach to robot localisation and navigation for indoor environments that are dominated by corridors. We describe our system and evaluate its performance in a small, but full-scale, test environment.

Navigating The Corridors Of Power : Using Rfid And Compass Sensors For Robot Localisation And Navigation, Yan Lee, Brian Mac Namee, John D. Kelleher

Conference papers

Localisation and navigation are still of the most important issues in mobile robotics. In certain indoor application scenarios Radio frequency identification (RFID) based absolute localisation has been found to be especially successful in supporting navigation. In this paper we examine the feasibility of an RFID and compass based approach to robot localisation and navigation for indoor environments that are dominated by corridors. We present a proof of concept system and show how it can be used to localized within and navigate through an environment.

Evaluating Sensorineural Hearing Loss With An Auditory Nerve Model Using A Mean Structural Similarity Measure, Andrew Hines, Naomi Harte

Conference papers

Hearing loss research has traditionally been based on perceptual criteria, speech intelligibility and threshold levels. The development of computational models of the auditory-periphery has allowed experimentation via simulation to provide quantitative, repeatable results at a more granular level than would be practical with clinical research on human subjects. This work seeks to create an objective measure to automate this inspection process and ranks hearing losses based on auditory-nerve discharge patterns. A systematic way of assessing phonemic degradation using the outputs of an auditory nerve model for a range of sensorineural hearing losses would aid in rapid prototyping development of speech-processing …

Development Of A Framework For The Assessment Of The Role And Impact Of Technology On The Public Procurement Process: An Irish Health Sector Study, Paul Davis

Doctoral

This thesis sets out to examine how the role and impact of technology, in the context of the public procurement process, can be assessed by addressing it as a single bounded structural entity. The thesis specifically examines the procurement process in the Irish Health Sector. This thesis takes the view that context for the procurement process is critical and that adopting a structuration approach to the examination of the process allows for a greater understanding of the role of technology. The thesis is built around a thematic structure which examines the changing relationship between information technology systems and organisational structure. …

In-Plane Thermal Conductivity Modeling Of Carbon Filled Liquid Crystal Polymer Based Resins, Tayloria N. G. Adams

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

Adding conductive carbon fillers to insulating thermoplastic resins increases composite electrical and thermal conductivity. Often, as much of a single type of carbon filler is added to achieve the desired conductivity, while still allowing the material to be molded into a bipolar plate for a fuel cell. In this study, varying amounts of three different carbons (carbon black, synthetic graphite particles, and carbon fiber) were added to Vectra A950RX Liquid Crystal Polymer. The in-plane thermal conductivity of the resulting single filler composites were tested. The results showed that adding synthetic graphite particles caused the largest increase in the in-plane thermal …

Investigation Into The Impact Of Grain Boundaries, Film Interface, And Crystallographic Orientation On The Ionic Conductivity Of Thin Film Gadolinium-Doped Ceria, Matthew M. Swanson

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

The research reported in this dissertation investigates the impact of grain boundaries, film interface, and crystallographic orientation on the ionic conductivity of thin film Gd-doped CeO2 (GDC).

Chapter 2 of this work addresses claims in the literature that submicron grain boundaries have the potential to dramatically increase the ionic conductivity of GDC films. Unambiguous testing of this claim requires directly comparing the ionic conductivity of single-crystal GDC films to films that are identical except for the presence of submicron grain boundaries. In this work techniques have been developed to grow GDC films by RF magnetron sputtering from a GDC target …

Measuring The Elastic Modulus Of Polymers Using The Atomic Force Microscope, Daniel Hoffman

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

Testing a new method of nanoindentation using the atomic force microscope (AFM) was the purpose of this research. Nanoindentation is a useful technique to study the properties of materials on the sub-micron scale. The AFM has been used as a nanoindenter previously; however several parameters needed to obtain accurate results, including tip radius and cantilever sensitivity, can be difficult to determine. To solve this problem, a new method to determine the elastic modulus of a material using the atomic force microscope (AFM) has been proposed by Tang et al. This method models the cantilever and the sample as two springs …

Spin-Strain Coupling In A 3-D Transition Metal Oxides, Ghous Bakhsh Narejo

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

ab-initio Hartree Fock (HF), density functional theory (DFT) and hybrid potentials were employed to compute the optimized lattice parameters and elastic properties of perovskite 3-d transition metal oxides. The optimized lattice parameters and elastic properties are interdependent in these materials. An interaction is observed between the electronic charge, spin and lattice degrees of freedom in 3-d transition metal oxides. The coupling between the electronic charge, spin and lattice structures originates due to localization of d-atomic orbitals. The coupling between the electronic charge, spin and crystalline lattice also contributes in the ferroelectric and ferromagnetic properties in perovskites. The cubic and tetragonal …

Characterization Of Legacy Organic Carbon In A Culturally Eutrophic Lake : The Role Of The Historic Carbon Deposition In The Time Course And Extent Of Lake Recovery , Phillip A. Depetro

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

The time course of lake recovery after a reduction in external loading of nutrients is often controlled by conditions in the sediment. Remediation of eutrophication is hindered by the presence of legacy organic carbon deposits, that exert a demand on the terminal electron acceptors of the lake and contribute to problems such as internal nutrient recycling, absence of sediment macrofauna, and flux of toxic metal species into the water column. Being able to quantify the timing of a lake’s response requires determination of the magnitude and lability, i.e., the susceptibility to biodegradation, of the organic carbon within the legacy deposit. …

Characterizing The Effects Of Turbulence On Sediment Oxygen And Sediment Nitrate Demand Using Flow-Through Reactors, Brandon J. Ellefson

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

Onondaga Lake has received the municipal effluent and industrial waste from the city of Syracuse for more than a century. Historically, 75 metric tons of mercury were discharged to the lake by chlor-alkali facilities. These legacy deposits of mercury now exist primarily in the lake sediments. Under anoxic conditions, methylmercury is produced in the sediments and can be released to the overlying water. Natural sedimentation processes are continuously burying the mercury deeper into the sediments. Eventually, the mercury will be buried to a depth where it no longer has an impact on the overlying water. In the interim, electron acceptor …

Quantification Of Relativistic Perturbation Forces On Spacecraft Trajectories, Nicholas Palma Mastricola

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

The intent of the work presented in this thesis is to show that relativistic perturbations should be considered in the same manner as well known perturbations currently taken into account in planet-satellite systems. It is also the aim of this research to show that relativistic perturbations are comparable to standard perturbations in speciffc force magnitude and effects. This work would have been regarded as little more then a curiosity to most engineers until recent advancements in space propulsion methods { e.g. the creation of a artiffcial neutron stars, light sails, and continuous propulsion techniques. These cutting-edge technologies have the potential …

Modeling Mechanical Response Of Heterogeneous Materials, Siladitya Pal

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

Heterogeneous materials are ubiquitous in nature and as synthetic materials. These materials provide unique combination of desirable mechanical properties emerging from its heterogeneities at different length scales. Future structural and technological applications will require the development of advanced light weight materials with superior strength and toughness. Cost effective design of the advanced high performance synthetic materials by tailoring their microstructure is the challenge facing the materials design community. Prior knowledge of structure-property relationships for these materials is imperative for optimal design. Thus, understanding such relationships for heterogeneous materials is of primary interest. Furthermore, computational burden is becoming critical concern in …

Energy Harvesting From Body Motion Using Rotational Micro-Generation, Edwar. Romero-Ramirez

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

Autonomous system applications are typically limited by the power supply operational lifetime when battery replacement is difficult or costly. A trade-off between battery size and battery life is usually calculated to determine the device capability and lifespan. As a result, energy harvesting research has gained importance as society searches for alternative energy sources for power generation. For instance, energy harvesting has been a proven alternative for powering solar-based calculators and self-winding wristwatches. Thus, the use of energy harvesting technology can make it possible to assist or replace batteries for portable, wearable, or surgically-implantable autonomous systems. Applications such as cardiac pacemakers …

Structural And Surface Property Characterization Of Titanium Dioxide Nanotubes For Orthopedic Implants, Tolou Shokuhfar

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

This research focused on the to modification of the surface structure of titanium implants with nanostructured morphology of TiO₂ nanotubes and studied the interaction of nanotubes with osteoblast cells to understand the parameters that affect the cell growth. The electrical, mechanical, and structural properties of TiO₂ nanotubes were characterized to establish a better understanding on the properties of such nanoscale morphological structures.

To achieve the objectives of this research work I transformed the titanium and its alloys, either in bulk sheet form, bulk machined form, or thin film deposited on another substrate into a surface of titania nanotubes …

Parametric Combustion Modeling For Ethanol-Gasoline Fuelled Spark Ignition Engines, Yeliana

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

Ethanol-gasoline fuel blends are increasingly being used in spark ignition (SI) engines due to continued growth in renewable fuels as part of a growing renewable portfolio standard (RPS). This leads to the need for a simple and accurate ethanol-gasoline blends combustion model that is applicable to one-dimensional engine simulation.

A parametric combustion model has been developed, integrated into an engine simulation tool, and validated using SI engine experimental data. The parametric combustion model was built inside a user compound in GT-Power. In this model, selected burn durations were computed using correlations as functions of physically based non-dimensional groups that have …

Water Absorption Of Carbon Nano-Fiber Enhanced Polyester/E-Glass Composite Materials, Basil I. Farah, Gail D. Jefferson, Kuang-Ting Hsiao

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, October 1-2, 2010. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 173-177

An Ab-Initio Study Of The Elastic Properties Of Important Group Iv Diborides At High Temperatures, Manny Gonzales

Open Access Theses & Dissertations

Presented is an ab-initio Molecular Dynamics (MD) study, employing the Density Functional Theory (DFT), of the lattice parameter, thermal expansion coefficients and elastic constants of ZrB₂, TiB₂ and HfB₂ as a function of temperature. The MD trajectories provide the equilibrium lattice parameters at finite temperatures, and the gradient of the energy from these equilibrium solutions is then used to calculate the components of the stiffness tensor. The results for ZrB₂ are shown to agree well with reported experimental results for the lattice parameters and elastic constants as a function of temperature.

Sodium Hydroxide Pretreatment And Enzymatic Hydrolysis Of Coastal Bermuda Grass, Ziyu Wang, Deepak R. Keshwani, Arthur P. Redding, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Coastal Bermuda grass was pretreated with NaOH at concentrations from 0.5% to 3% (w/v) for a residence time from 15 to 90 minutes at 121 °C. The pretreatments were evaluated based on total lignin removal and production of total reducing sugars, glucose and xylose from enzymatic hydrolysis of the pretreated biomass. Up to 86% lignin removal was observed. The optimal NaOH pretreatment conditions at 121 °C for total reducing sugars production as well as glucose and xylose yields are 15 minutes and 0.75% NaOH. Under these optimal pretreatment conditions, total reducing sugars yield was about 71% of the theoretical maximum, …

Nonparametric Estimation Of Derivatives With Applications, Benjamin Hall

University of Kentucky Doctoral Dissertations

We review several nonparametric regression techniques and discuss their various strengths and weaknesses with an emphasis on derivative estimation and confidence band creation. We develop a generalized C(p) criterion for tuning parameter selection when interest lies in estimating one or more derivatives and the estimator is both linear in the observed responses and self-consistent. We propose a method for constructing simultaneous confidence bands for the mean response and one or more derivatives, where simultaneous now refers both to values of the covariate and to all derivatives under consideration. In addition we generalize the simultaneous confidence bands to account for heteroscedastic …

Laminar-Turbulent Transition For Attached And Separated Flow, Qian Zhang

University of Kentucky Doctoral Dissertations

A major challenge in the design of turbomachinery components for aircraft gas turbine engines is high cycle fatigue failures due to flutter. Of particular concern is the subsonic/transonic stall flutter boundary which occurs at part speed near the stall line. At these operating conditions the incidence angle is large and the relative Mach number is high subsonic or transonic. Viscous effects dominate for high incidence angles.

In order to predict the flutter phenomena, accurate calculation of the steady and unsteady aerodynamic loading on the turbomachinery airfoils is necessary. The development of unsteady aerodynamic models to predict the unsteady forces and …

Targeted Polymeric Biomaterials For The Prevention Of Post Surgical Adhesions, John M. Medley

University of Kentucky Doctoral Dissertations

Despite recent advances in surgical technique and the development of numerous therapeutic agents, the formation post surgical adhesions (PSA) continues to cause complications for many patients. In this research, we have employed a rational system to develop a novel treatment to address this clinical need. Based on an understanding of the biochemical events that lead to PSA formation, a series of targeted polymeric biomaterials was designed to interrupt the fibrin gel matrix propagation and suppress PSA formation.

Using group transfer polymerization, a series of well controlled block copolymers of polyacrylic acid and poly(ethylene glycol-methacrylate) based materials was synthesized. Subsequent functionalization …

Engineering Sport Safety: A Study Of Equestrian Cross Country Eventing, Katherine M. Kahmann

University of Kentucky Master's Theses

The sport of equestrian cross country eventing has seen many serious and even fatal injuries due to rotational horse falls in recent years. The sport originally consisted of horse and rider teams jumping stationary, wood fences. However, in a move towards increasing safety for horses and riders, frangible and deformable safety devices have been emerging in the field. This thesis provides an overview of safety designs that are currently available and those that are on the horizon. Also, a path-finder method of evaluating and developing safety fence designs was outlined and applied to two distinct designs, a hinged gate and …

Interfacial Thermal Conductivity Using Multiwall Carbon Nanotubes, Carissa Don Russell

University of Kentucky Master's Theses

Shrinking volume, coupled with higher performance, microprocessors and integrated circuits have led to serious heat dissipation issues. In an effort to mitigate the excessive amounts of waste heat and ensure electronic survivability, heat sinks and spreaders are incorporated into heat generating device structures. This inevitability creates a thermal pathway through an interface. Thermal interfaces can possess serious thermal resistances for heat conduction. The introduction of a thermal interface material (TIM) can drastically increase the thermal performance of the component. Exceptional thermal properties of multiwall carbon nanotubes (MWCNTs) have spurred interest in their use as TIMs. MWCNTs inherently grow in vertically-oriented, …

Experimental Study Of Blast Resistant Glazing System Response To Explosive Loading, William Chad Wedding

University of Kentucky Master's Theses

This thesis recounts the experimental study of the dynamic response of a blast resistant glazing system to explosive loading. A combination of triaxial force sensors, pressure gauges, and laser displacement gauges capture the response in detail over a wide range of scenarios. The scenarios include low level blast loading to characterize the reaction at points around the perimeter of the window, moderate level blast loading to examine the repeatability of the blast scenario, and high level blast loading to capture the response during failure as the tensile membrane forms. The scenarios are modeled via an analytical Single-Degree-of-Freedom model as well …