Engineering Commons^™

Microstructural Evolution And Physical Behavior Of Palladium And Osmium-Ruthenium Noble Metal Films, Wen-Chung Li

University of Kentucky Doctoral Dissertations

Nanostructured noble metals exhibit novel physical, mechanical and chemical behavior, and hold promise for applications such as gas sensing and electron emission. A strong emphasis was placed on the processing and characterization of these materials, in the form of nanoporous or nanocrystalline thin films. Palladium-based and osmium-ruthenium alloys were investigated in this dissertation research and will be presented as follows:

(1) Preparation and Characterization of Nanoporous Metal Thin Films

(2) Characterization of Osmium-Ruthenium Coatings

Nanoporous palladium (np-Pd) thin films were prepared by dealloying co-sputtered palladium-nickel precursor alloys. Nanoporous structures were created with 3-D interconnected ligaments and open pores. Size of …

Detailed Surface Analysis Of Lip Seal Elastomers Ran Against Shafts Manufactured With Triangular Cavities, Vetrivel Kanakasabai

University of Kentucky Master's Theses

Previous experimental and theoretical results indicate that the keys to successful radial lip seals are the surface characteristics of the shaft and the microasperity pattern that develops due to wear on the elastomer. In this study, the lip seal was tested against five different patterns of shaft surface: plain stainless steel, triangular cavities oriented towards air, triangular cavities oriented towards oil, triangular cavities leading and triangular cavities lagging. Using Zygo optical profilometer and scanning electron microscope, a thorough surface characterization of the micro-asperities and microcavities is done on the lip seal elastomer. Correlation coefficients were calculated between the surface parameters …

Nebraska Summary: S701 Challenger Mt535b, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S699 Massey Ferguson 6495, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Integration Of An Extended Octagonal Ring Transducer And Soil Coulterometer For Identifying Soil Compaction, Santosh K. Pitla, Larry G. Wells, Scott A. Shearer

Biosystems and Agricultural Engineering Faculty Publications

The soil coulterometer is an "on-the-go" electro-mechanical system which collects impedance force data at multiple depths using an oscillating coulter. During the initial testing (summer 2006), only vertical soil impedance force data was collected using a pressure sensor. To improve the performance of the coulterometer, an extended octagonal ring transducer was integrated into the system to collect both the horizontal and vertical impedance forces given by the soil. In the summer of 2007, data was collected using the revised sensor from a typical central Kentucky field setting in a 0.8-ha (2-acre) plot. Four passes were made with the coulterometer. Seventy …

True Binary Random Number Generator Based On A Double Scroll Attractor For Encryption, Marta Blaszczyk

Theses

Random binary sequences play an important role in modem digital communication systems. Their usage for providing secure communication between parties became indelible in cryptosystems. In increased access to the Internet network, random sequences are employed for ensuring that personal information remains confidential. To provide completely unpredictable keys in encipherment the usage of a true random number generator is necessary. True random bit streams are required to assure the security provided by the one-time pad encryption algorithm which is provably unbreakable.

The central objective of this research is the production of such random sequences for short key generation in data encryption …

Rf Mems Capacitors For Sdr, Yamuna Kuberappa

Theses

Micro electro mechanical systems (MEMS) applications in radio frequency (RF) and microwave electronics are revolutionizing the progress in wireless communications. In particular, MEMS switchable/tunable capacitors can facilitate the realization of multistandard software defined transceivers, offering better performance than existing solutions.

In this thesis, characterisation and RF modelling of MEMS switchable/tunable capacitors and the technical requirements for their application in multiband wireless transceiver circuits in a software defined radio (SDR) are described. The first device considered is a curled cantilever capacitive switch, configured in both shunt and series configuration where the capacitance is limited to two stable states. The second device, …

A Virtual Training Environment For Temporal Bone Surgery, Denis Stack

Theses

A virtual training environment for temporal bone surgery incorporating haptic, visual and audio feedback is presented in this work. Data are derived from Computed Tomography (CT) scans, thus patient-specific cases may be examined in the simulator.

Two main classes of volume haptic algorithm exist for virtual surgery, namely proxy-based and non proxy-based. A review of the evolution of relevant haptic algorithms is presented. Proxy-based and non proxy-based algorithms are implemented and their performance measured against each other by comparison with real-world force data. An improved proxy-based feedback algorithm is also presented. This algorithm uses a spherical proxy which prevents the …

Trust Based Agent Geographic Coalition Formation For Intelligent Transportation Systems, Gary O'Connor

Theses

In recent years there has been an increase in the area of applied research for the intelligent transport domain. This surge in research has many contributing factors such as: advancements in information technologies, substantial escalations of traffic congestion and the advent of wireless networking. The possibility of collaboration among vehicles and roadside infrastructure enriches transportation systems, where the goals of improved safety, traffic efficiency and environmental benefits can be addressed. The primary objective of these Intelligent Transportation Systems (ITS) is the creation of advanced road traffic safety systems for improved traffic safety, efficiency and travelling comfort. These systems provide a …

Cross-Verified, Combined Methodologies For High Frequency Electrical Characterisation Of Electronic Packaging, Eoin Mcgibney

Theses

Methodologies for cross-verified, wide bandwidth (50MHz-20GHz) electrical model extraction for as-manufactured electronic packaging and interconnection are presented. They are presented in the context that packaging and interconnection is now following a rapidly-evolving Moore’s-type Law in terms of new generations of packaging and interconnection materials, technologies and manufacturing processes. Significant frequency content is also increasing while, at the same time, final product cost constraints mean that packages and circuit boards must typically be manufactured using low cost materials and mass-manufacturing processes, often geographically remote, with their inherently higher levels of variability. Wide bandwidth signal integrity analysis cannot be performed during electronic …

Design, Analysis, And Optimization Of Diffractive Optical Elements Under High Numerical Aperture Focusing, Toufic Jabbour

Electronic Theses and Dissertations

The demand for high optical resolution has brought researchers to explore the use of beam shaping diffractive optical elements (DOEs) for improving performance of high numerical aperture (NA) optical systems. DOEs can be designed to modulate the amplitude, phase and/or polarization of a laser beam such that it focuses into a targeted irradiance distribution, or point spread function (PSF). The focused PSF can be reshaped in both the transverse focal plane and along the optical axis. Optical lithography, microscopy and direct laser writing are but a few of the many applications in which a properly designed DOE can significantly improve …

Macroscopic Traffic Safety Analysis Based On Trip Generation Characteristics, Chowdhury Siddiqui

Electronic Theses and Dissertations

Recent research has shown that incorporating roadway safety in transportation planning has been considered one of the active approaches to improve safety. Aggregate level analysis for predicting crash frequencies had been contemplated to be an important step in this process. As seen from the previous studies various categories of predictors at macro level (census blocks, traffic analysis zones, census tracts, wards, counties and states) have been exhausted to find appropriate correlation with crashes. This study contributes to this ongoing macro level road safety research by investigating various trip productions and attractions along with roadway characteristics within traffic analysis zones (TAZs) …

Vectorpad: A Tool For Visualizing Vector Operations, Jared Bott

Electronic Theses and Dissertations

Visualization of three-dimensional vector operations can be very helpful in understanding vector mathematics. However, creating these visualizations using traditional WIMP interfaces can be a troublesome exercise. In this thesis, we present VectorPad, a pen-based application for three-dimensional vector mathematics visualization. VectorPad allows users to define vectors and perform mathematical operations upon them through the recognition of handwritten mathematics. The VectorPad user interface consists of a sketching area, where the user can write vector definitions and other mathematics, and a 3D graph for visualization. After recognition, vectors are visualized dynamically on the graph, which can be manipulated by the user. A …

Understanding Practical Limits To Heavy Truck Drag Reduction, Drew Landman, Richard Wood, Whitney Seay, John Bledsoe

Mechanical & Aerospace Engineering Faculty Publications

A heavy truck wind tunnel test program is currently underway at the Langley Full Scale Tunnel (LFST). Seven passive drag reducing device configurations have been evaluated on a heavy truck model with the objective of understanding the practical limits to drag reduction achievable on a modern tractor trailer through add-on devices. The configurations tested include side skirts of varying length, a full gap seal, and tapered rear panels. All configurations were evaluated over a nominal 15 degree yaw sweep to establish wind averaged drag coefficients over a broad speed range using SAE J1252. The tests were conducted by first quantifying …

Modeling Microbiological And Chemical Processes In Municipal Solid Waste Bioreactor: Development And Applications Of A Three-Pha, Nitin Gawande

Electronic Theses and Dissertations

The numerical computer models that simulate municipal solid waste (MSW) bioreactor landfills have mainly two components--a biodegradation process module and a multi-phase flow module. The biodegradation model describes the chemical and microbiological processes of solid waste biodegradation. The models available to date include predefined solid waste biodegradation reactions and participating species. In a bioreactor landfill several processes, such as anaerobic and aerobic biodegradation, nitrogen and sulfate cycling, precipitation and dissolution of metals, and adsorption and gasification of various anthropogenic organic compounds, occur simultaneously. These processes may involve reactions of several species and the available biochemical models for solid waste biodegradation …

The Effects Of Inorganic Solids And Certain Gases On The Thermal Decomposition Of Catechol, Jerome Apilan Robles

LSU Doctoral Dissertations

In order to investigate the effects of calcium carbonate and iron oxide on the thermal decomposition of solid fuels, we have constructed an isothermal flow reactor to perform experiments on the model compound catechol (ortho-dihydroxybenzene), a phenol-type compound representative of coal, wood and biomass. Calcium carbonate and iron oxide are inorganic components of coal and wood, which have demonstrated catalytic properties in thermal reactions and are commercially used to enhance the conversion of solid fuels. In this study, the effects of the inorganic solids on pyrolysis and combustion are conducted through identification and quantification of the products formed after subjecting …

Integrated Data-Driven Techniques For Environmental Pollution Monitoring, Swathi Pakalapati

LSU Doctoral Dissertations

The adverse health e_x000B_ffects of tropospheric ozone around urban zones indicate a substantial risk for many segments of the population. This necessitates the short term forecast in order to take evasive action on days conducive to ozone formation. Therefore it is important to study the ozone formation mechanisms and predict the ozone levels in a geographic region. Multivariate statistical techniques provide a very e_x000B_ffective framework for the classifi_x000C_cation and monitoring of systems with multiple variables. Cluster analysis, sequence analysis and hidden Markov models (HMMs) are statistical methods which have been used in a wide range of studies to model the …

Task Scheduling And Placement For Reconfigurable Devices, Mostafa Elbidweihy

LSU Doctoral Dissertations

Partially reconfigurable devices allow the execution of different tasks at the same time, removing tasks when they finish and inserting new tasks when they arrive. This dissertation investigates scheduling and placing real-time tasks (tasks with deadline) on reconfigurable devices. One basic scheduler is the First-Fit scheduler. By allowing the First-Fit scheduler to retry tasks while they can satisfy their deadlines, we found that its performance can be enhanced to be better than other schedulers. We also proposed a placement idea based on partitioning the reconfigurable area into regions of various widths, assigning a task to a region based on its …

Preliminary Investigation Of Novel Bone Graft Substitutes Based On Strontium-Calcium-Zinc-Silicate Glasses, D. Boyd, G. Carroll, Mark R. Towler, C. Freeman, P. Farthing, I. M. Brook

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone graft procedures typically require surgeons to harvest bone from a second site on a given patient (Autograft) before repairing a bone defect. However, this results in increased surgical time, excessive blood loss and a significant increase in pain. In this context a synthetic bone graft with excellent histocompatibility, built in antibacterial efficacy and the ability to regenerate healthy tissue in place of diseased tissue would be a significant step forward relative to current state of the art philosophies. We developed a range of calcium-strontium-zinc-silicate glass-based bone grafts and characterized their structure and physical properties, then evaluated their in vitro …

An Introduction To Dezert-Smarandache Theory (Dsmt), Jean Dezert, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The management and combination of uncertain, imprecise, fuzzy and even paradoxical or highly conflicting sources of information has always been, and still remains today, of primal importance for the development of reliable modern information systems involving artificial reasoning. In this introduction, we present a survey of our recent theory of plausible and paradoxical reasoning, known as Dezert-Smarandache Theory (DSmT), developed for dealing with imprecise, uncertain and conflicting sources of information. We focus our presentation on the foundations of DSmT and on its most important rules of combination, rather than on browsing specific applications of DSmT available in literature. Several simple …

Optimizing Computer-Aided Colonic Polyp Detection For Ct Colonography By Evolving The Pareto Front, Jiang Li, Adam Huang, Jack Tao, Jiamin Liu, Robert L. Van Uitert, Nicholas Petrick, Ronald Summers

Electrical & Computer Engineering Faculty Publications

A multiobjective genetic algorithm is designed to optimize a computer-aided detection (CAD) system for identifying colonic polyps. Colonic polyps appear as elliptical protrusions on the inner surface of the colon. Curvature-based features for colonic polyp detection have proved to be successful in several CT colonography (CTC) CAD systems. Our CTC CAD program uses a sequential classifier to form initial polyp detections on the colon surface. The classifier utilizes a set of thresholds on curvature-based features to cluster suspicious colon surface regions into polyp candidates. The thresholds were previously chosen experimentally by using feature histograms. The chosen thresholds were effective for …

Rapid Sensor Technology: A Risk And System Complexity Analyses Of Early Detection Of Influenza-Like-Illnesses, Cesar Ariel Pinto, Ipek Bozkurt

Engineering Management & Systems Engineering Faculty Publications

The development of effective and reliable methods to defend the nation against biological terrorism remains an urgent challenge to researchers in the areas of risk, bio-defense, public health, and emergency medicine. The emerging threat of the avian flu pandemic also highlights the unpreparedness of our nation's health care system to meet a highly contagious and infectious disease outbreak. The implementation of a rapid sensor technology for early detection of influenza-like-illness provides possible opportunities, as well as problems. Bounding and defining such a complex problem is one of the first challenges this research addresses. Approaching this problem from various perspectives such …

Embedding Simulation Education Into The Engineering Management Body Of Knowledge, Andreas Tolk, Ghaith Rabadi, Donald N. Merino

Computational Modeling & Simulation Engineering Faculty Publications

The American Society for Engineering Management (ASEM) established a Body of Knowledge (BoK). As simulation is of growing interest to engineers in general and to engineering managers in particular, simulation is part of this documentation of domains of interest that characterise the profession. The basis for the Body of Knowledge comprises of established and accredited curricula and additional input from practitioners of the field. As it is essential to cover the basic topics and core competences as well as application specific domain knowledge, the simulation education for engineers is categorised into topics on simulation theory and simulation application.

Vibrational And Mechanical Properties Of 10 Mol % Sc2o3-1 Mol % Ceo2- Zro2 Electrolyte Ceramics For Solid Oxide Fuel Cells, Svetlana Lukich

Electronic Theses and Dissertations

Solid Oxide Fuel Cells (SOFCs) are emerging as a potential breakthrough energy conversion technology for clean and efficient production of electricity and heat from hydrogen and hydrocarbon fuels. Sc0.1Ce0.01ZrO2 electrolytes for Solid Oxide Fuel Cells are very promising materials because their high ionic conductivity in the intermediate temperature range 700°C-800°C. The vibration response of cubic and rhombohedral (β) 10 mol%Sc2O3 - 1 mol%CeO2 - ZrO2(Sc0.1Ce0.01ZrO2 ) both at room and high-temperatures is reported. The in-situ heating experiments and ex-situ indentation experiments were performed to characterize the vibrational behavior of these important materials. A temperature and stress-assisted phase transition from cubic …

Saw Reflective Transducers And Antennas For Orthogonal Frequency Coded Saw Sensors, Bianca Maria Santos

Electronic Theses and Dissertations

Passive sensors that vary its impedance per measured parameter may be used with surface acoustic wave (SAW) reflective transducers (SRT) for wireless acquisition of the measurand. The device is composed of two transducers, where one, which may be attached to an antenna, is used to launch the wave within the device substrate, and the other is where the sensor load is attached to. The latter is able to reflect the incident wave. How much power is reflected is determined by the attached sensor load. Amplitude variations as well as peak frequency variations of the SRT reflectivity response are explored in …

An Analysis Of Silver Candlesticks From A Casting Point Of View: Originals, Copies, Forgeries, Jaromir Audy, Emil Evin

Research outputs pre 2011

Collecting silver artefacts has traditionally been a very popular hobby. Silver is addictive, therefore the number of potential collectors and investors appears to grow each year. Unfortunately, increases in the interest and buying potentials resulted in a number of forgeries manufactured and introduced to the open antique market. The items such as early silver candlesticks dictate a very high price, for many high quality fakes show very good appearances and matching similarities with originals. Such copies are traditionally manufactured by casting using the original items as patterns. Small details and variances in design features, position and shape of hallmarks, including …

Biomedical Technology: Supporting Movement, Petros Katsioloudis

STEMPS Faculty Publications

According to the National Institute on Disability and Rehabilitation Research, an estimated 8.5 million children 21 years and younger have a disability (Jans & Stoddard, 1999). After about a decade, with the development of new and sophisticated materials (aluminum alloys, titanium alloys, and carbon fibers) and the integration of electronics, it was then possible to significantly improve the performance of prostheses, built with the so-called endo skeletal (or skeletal-modular) method (Mora, Beratni & Pedrotti, 2006).

Asset Management Application Towards An Improved Right Of Way Acquisition, Dora Oralia Francis

Open Access Theses & Dissertations

The purpose of this research is to discover a most suitable approach when the right of way acquisition process begins. As soon as it is known that the right of way acquisitions begin, speculations are made to parcels in order to increase the values of these parcel. Different types of speculations can be made, at a different phase of the right of way (ROW) acquisition process. The parcel cost can vary due to speculations according to the phase of the right of way acquisition process. To help assist the Texas Department of Transportation (TxDOT) on the right of way acquisition …

Art In A New Light: Design And Assessment Of Illuminants To Reduce Photochemical Degradation Of Works Of Art, Monica Fabiola Delgado

Open Access Theses & Dissertations

The purpose of this research is to design the best lighting that will minimize long term photochemical degradation of Old Master Drawings and/or other works of art, while maintaining the patron's appreciation of the object's color and detail. The present approach is a technological refinement to the basic underlying earlier work on fluorescent lighting by W. A. Thornton, W.A. at General Electric1. Thin-film dielectric, multi-coating technology is used to create filters that eliminate ultraviolet light, near infrared light and significant unnecessary parts from the visible spectrum, thus maximizing the reduction in photochemical degradation, while maintaining optimal color rendering. Three interference …

Additive Layer Manufacturing Of Ti-6al-4v By Electron Beam Melting From Powder Particles: Solid, Mesh And Foam Components Study, Sara M. Gaytan

Open Access Theses & Dissertations

Additive Manufacturing by Electron Beam Melting Rapid Manufacturing is a technology that consists of the fabrication of a CAD design by melting powder particles in a layer by layer fashion. In this study, Ti-6Al-4V has been utilized to fabricate solid, mesh and foam components by EBM technologies. Powder analysis of Ti-6Al-4V was performed to obtain a better understanding of the porosity obtained by the system. After proper optimization of the machine, and porosity control, microstructural analysis was performed to the components already mentioned and correlated by transmission electron microscopy. Besides the microstructural analysis, tensile and hardness testing was performed to …