Engineering Commons^™

Flexible Electronics Using Ion Implantation To Adhere Polymer Substrate To Single Crystal Silicon Substrate, Terry L. Alford, Douglas C. Thompson Jr., Hyunchul Kim, Michael A. Nastasi, James W. Mayer, Daniel Adams

Department of Mechanical and Materials Engineering: Faculty Publications

An electronic apparatus uses a single crystalline silicon Substrate disposed adjacent to a flexible substrate. The electronic apparatus may be a flexible flat panel display, or a flexible printed circuit board. The flexible substrate can be made from polymer, plastic, paper, flexible glass, and stainless steel. The flexible substrate is bonded to the single crystalline substrate using an ion implantation process. The ion implantation process involves the use of a noble gas Such as hydrogen, helium, Xenon, and krypton. A plurality of semiconductor devices are formed on the single crystalline silicon Substrate. The semi conductor devices may be thin film …

The Effect Of Particle Surface Area To Volume Ratio On Ion Release From Cocr Spheres, Darin J. Grandfield

Master's Theses

In 2005, over 200,000 Americans underwent a hip arthroplasty, the replacement of a hip joint with an artificial prosthesis. Of these arthroplasties, metal-on-metal type implants represent an increasing usage percentage. Metal-on-metal implants are selected largely for their low volumetric wear rate, durability, and resistance to corrosion. In spite of these advantages, little is known concerning the long-term consequences of heavy metal alloy use in the body, although early research indicates potentially carcinogenic results. This thesis is a preliminary investigation into these long term effects and their root causes.

An improved comprehension of the corrosion kinetics and the rate of ion …

Evaluating The Electrical Response Of Polyaniline To Mechanical Strain, Matthew L. Goebel

Master's Theses

This thesis focuses on the electrical output of polyaniline films subjected to uniaxial strain in hydrochloric acid solutions. Polyaniline belongs to novel class of materials known as conducting polymers. Alternating single and double bonds in the backbone of conducting polymers allow them to transmit electric charge when they are doped with negatively charged ions. Modifying the degree of doping and other electrical/chemical treatments allow conducting polymers to exhibit conducting, semi-conducting, or insulating electrical properties. Resilient mechanical properties, good processability, and low cost make conducting polymers good candidates for applications traditionally held by metals and semi-conductors.

When tensile strain is applied …

Probabilistic Interpretation Of Fuzzy Transforms And Fuzzy Control, Irina Perfilieva, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical applications, it turns out to be useful to use the notion of fuzzy transform: once we have non-negative functions A₁(x), ..., A_n(x), with A₁(x) + ... + A_n(x) = 1, we can then represent each function f(x) by the coefficients F_i which are defined as the ratio of two integrals: of f(x) * A_i(x) and of A_i(x). Once we know the coefficients F_i, we can (approximately) reconstruct the original function f(x) as F₁ * A₁(x) + ... + F …

South Burlington Vt: New Urbanist South Village, Jack Kartez, Richard Barringer

Planning

The 220 acre master plan for South Village, the largest project in the City of South Burlington’s history, encompasses multiple housing types and innovative provisions for affordable housing. It integrates housing with open space and natural resource conservation, including a major Community Supported Agriculture project developed by a nonprofit partner, the Intervale Foundation. While not a mixed-use project (that is, commercial as well as residential development), South Village nonetheless represents a qualitative change in approach for South Burlington by incorporating large-scale open space preservation as part of development and multiple housing-types in one project. The case study recounts events leading …

Engineering Design Under Imprecise Probabilities: Computational Complexity, Vladik Kreinovich

Departmental Technical Reports (CS)

In engineering design problems, we want to make sure that a certain quantity c of the designed system lies within given bounds -- or at least that the probability of this quantity to be outside these bounds does not exceed a given threshold. We may have several such requirements -- thus the requirement can be formulated as bounds [Fc(x); Fc(x)] on the cumulative distribution function Fc(x) of the quantity c; such bounds are known as a p-box.

The value of the desired quantity c depends on the design parameters a and the parameters b characterizing the environment: c = f(a; …

Measurement's Result And Its Error As Fuzzy Variables: Background And Perspectives, Gennady N. Solopchenko, Konstantin K. Semenov, Vladik Kreinovich, Leon Reznik

Departmental Technical Reports (CS)

The possibility of using fuzzy variables for describing measurands and their error characteristics is investigated. The elementary arithmetic operations within the limits of such representation are considered.

Looking For Entropy Rate Constancy In Spoken Dialog, Alejandro Vega, Nigel Ward

Departmental Technical Reports (CS)

The entropy constancy principle describes the tendency for information in language to be conveyed at a constant rate. We explore the possible role of this principle in spoken dialog, using the ``summed entropy rate,'' that is, the sum of the entropies of the words of both speakers per second of time. Using the Switchboard corpus of casual dialogs and a standard ngram language model to estimate entropy, we examine patterns in entropy rate over time and the distribution of entropy across the two speakers. The results show effects that can be taken as support for the principle of constant entropy, …

Equations Without Equations: Challenges On A Way To A More Adequate Formalization Of Causality Reasoning In Physics, Roberto Araiza, Vladik Kreinovich, Juan Ferret

Departmental Technical Reports (CS)

Not all mathematical solutions to physical equations are physically meaningful: e.g., if we reverse all the molecular velocities in a breaking cup, we get pieces self-assembling into a cup. The resulting initial conditions are "degenerate": once we modify them, self-assembly stops. So, in a physical solution, the initial conditions must be "non-degenerate".

A challenge in formalizing this idea is that it depends on the representation. Example 1: we can use the Schroedinger equation to represent the potential field V(x)=F(f,...) as a function of the wave function f(x,t) and its derivatives. The new equation dF/dt=0 is equivalent to the Schroedinger equation, …

Routing In The Dark: Pitch Black, Nathan S. Evans

Electronic Theses and Dissertations

In many networks, such as mobile ad-hoc networks and friend-to-friend overlay networks, direct communication between nodes is limited to specific neighbors. Friendto-friend “darknet” networks have been shown to commonly have a small-world topology; while short paths exist between any pair of nodes in small-world networks, it is non-trivial to determine such paths with a distributed algorithm. Recently, Clarke and Sandberg proposed the first decentralized routing algorithm that achieves efficient routing in such small-world networks.

Herein this thesis we discuss the first independent security analysis of Clarke and Sandberg’s routing algorithm. We show that a relatively weak participating adversary can render …

Lifetime Estimation Of Wireless Body Area Sensor Network For Patient Health Monitoring, Frank Agyei-Ntim

Electronic Theses and Dissertations

Wireless Body Area Sensor Networks (WBASN) is an emerging technology which utilizes wireless sensors to implement real-time wearable health monitoring of patients to enhance independent living. These sensors can be worn externally to monitor multiple bio-parameters (such as blood oxygen saturation (SpO2), blood pressure and heart activity) of multiple patients at a central location in the hospital.

In health monitoring, the loss of critical or emergency information is a serious issue so there is a concern for quality of service which needs to be addressed. It is important to have an estimate of the time the first node will fail …

Conductivity Sensors To Monitor Cover-Zone Performance, W. J. Mccarter, T. M. Chrisp, G. Starrs, E. Owens, Niall Holmes, L. Basheer, S. V. Nanukuttan, M. Basheer

Conference papers

This paper presents developments in the use of an embedded, multi-electrode conductivity sensor to study the response of the concrete cover-zone to environmental action. The sensor enables an evaluation of the temporal and spatial variation of electrical conductivity thereby allowing an integrated assessment of the cover-zone. Conductivity sensors were embedded within concrete samples to study the cover-zone response to cyclic wetting and drying under laboratory conditions. This work was extended to include the use of remote interrogation methods to study samples placed at a marine exposure site and preliminary results are presented.

Satellite Formation Flight Navigation Using The Clohessy-Wiltshire Equations, Anna Kimmich

Aerospace Engineering

This report presents the design and simulation of a satellite navigation program using Matlab. The program allows any number of independent satellites to navigate in a co-planar cluster formation in a circular orbit with no input besides its location coordinates from a simulated GPS unit and the relative location of other satellites from a simulated on-board sensor. This navigation program uses a potential field-like function to calculate the desired satellite position within the formation. It uses the Clohessy-Wiltshire equations to calculate the impulsive maneuvers needed to achieve and maintain the formation.

The Effects Of Thermal Annealing On The Obliquely Deposited Ag–Ge–S Thin Films, F. Wang, W. P. Dunn, M. Jain, C. De Leo, N. Vicker, Richard N. Savage, Xiaomin Jin, S. Mamedov, P. Boolchand

Materials Engineering

Obliquely deposited thin films of ternary Ag–Ge–S glasses are characterized in this work. Thin films are fabricated in a vacuum thermal evaporator at different evaporation angles and examined by Raman spectroscopy. The Raman mode frequency of GeS₄ corner-sharing (CS) structure of the as-deposited films display a red-shift as a function of Ag content due to reduced global connectivity, and therefore decreased network stress. Film thickness of normally deposited thin films is significantly less when compared against obliquely deposited ones. Sulfur-ring (S₈) modes are observed in thin films but not in corresponding bulk material. Thermal annealing of thin …

Hydrological Behavior Of Grasslands Of The Sandhills Of Nebraska: Water And Energy Balance Assessment From Measurements, Treatments And Modeling, Venkataramana Sridhar, David A. Wedin

Civil Engineering Faculty Publications and Presentations

Understanding energy and water balance processes in the Sandhills is crucial to assess the land-atmosphere feedback effects. The Sandhills located in western Nebraska covers a vast grassland ecosystem with limited variability in vegetation and soil. However, the combined effect of topography, land cover and micrometeorology by subjecting the land surface to various disturbances and treatments is rarely studied. The NOAH Land Surface Model was used to estimate net radiation, latent, sensible and ground heat fluxes as well as water balance components for two growing seasons between 2005 and 2006 in various plots at the Grasslands Destabilization Experimental site where these …

Web Based Classes For Enhancement Of Prelaboratory Lectures, Tiffany Hesser, Michael Collura

Chemistry and Chemical Engineering Faculty Publications

The use of web classes, such as Tegrity Campus1, as a supplement to pre laboratory reading or a replacement for pre laboratory lectures could become a standard tool in laboratory education protocol. In classes with multiple lab sections and instructors, pre laboratory lectures can lack consistency and it can be difficult to gauge the students’ level of preparation. With the ever increasing exposure to technology, students generally prefer information in a digital and multimedia form, rather than textbook readings. Therefore, this method can prove to better prepare students prior to laboratory experiments, increasing the overall understanding of the chemical reactions …

Year Five Annual Report: Activities, Findings And Evaluators' Reports, Ncete Faculty

Reports to NSF

The National Center for Engineering and Technology Education (NCETE) received funding from the National Science Foundation on September 15, 2004. Originally NCETE proposed the following goals for the Center: • To build capacity in graduate education and develop a new cadre of leaders who are engaged in research, teacher preparation, and professional development with the knowledge and skill to integrate engineering into technology education • To conduct research in how students learn engineering and technological concepts; how students learn design and problem solving, assessment and evaluation strategies; and how best to prepare technology teachers • To refocus technology teacher education …

Dredging And Dredged Material Beneficial Use In Ireland, Colm Sheehan, Joseph R. Harrington, Jerry Murphy

Publications

This article provides an overview of the dredging industry in Ireland which may be small by international standards but is of critical importance to the nation’s Ports and Harbours. Open sea disposal of dredged material is most common, but a range of beneficial uses for the coarser fraction of dredged material has been practiced. Details on different aspects of dredging in Ireland are presented including a review of current beneficial uses. A specific site at Fenit Harbour in Tralee Bay is examined to assess the potential for a specific beneficial use of dredged material using geotubes in breakwater and revetment …

Force Chains And Resonant Behavior In Bending Of A Granular Layer On An Elastic Support, Kitti Rattanadit, Florin Bobaru, Konlayut Promratana, Joseph A. Turner

Department of Engineering Mechanics: Faculty Publications

In this paper we investigate the interaction between a granular layer and an elastic foundation using a coupled Discrete Element Method-Finite Element Method (DEM–FEM) computational model. We use this dynamics code to simulate quasi-static bending of the granular layer and we observe the changes taking place in the structure of the force chains for two cases: with and without rolling resistance. A reversal of the arches formed in the force chains leads to a bending resistance similar to that observed in dynamic experiments on resonant behavior under bending of a layer of sand in a container with an elastic bottom. …

Effects Of Learning Rate On The Performance Of The Population Based Incremental Learning Algorithm, Ganesh K. Venayagamoorthy, K. A. Folly

Electrical and Computer Engineering Faculty Research & Creative Works

The effect of learning rate (LR) on the performance of a newly introduced evolutionary algorithm called population-based incremental learning (PBIL) is investigated in this paper. PBIL is a technique that combines a simple genetic algorithm (GA) with competitive learning (CL). Although CL is often studied in the context of artificial neural networks (ANNs), it plays a vital role in PBIL in that the idea of creating a prototype vector in learning vector quantization (LVQ) is central to PBIL. In PBIL, the crossover operator of GAs is abstracted away and the role of population is redefined. PBIL maintains a real-valued probability …

Reconstruction Of The Upper Torso Using X-Ray Imagery, Thomas Wischgoll, Christopher Koehler

Computer Science and Engineering Faculty Publications

No abstract provided.

Chilling Out In The Sim: The Need For Icing Training., Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Flying Precision Approaches Precisely, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Temperature Dependence Of Hot-Carrier Relaxation In Pbse Nanocrystals: An Ab Initio Study, Hua Bao, Bradley F. Habenicht, Oleg V. Prezhdo, X Ruan

Birck and NCN Publications

Temperature-dependent dynamics of phonon-assisted relaxation of hot carriers, both electrons and holes, is studied in a PbSe nanocrystal using ab initio time-domain density-functional theory. The electronic structure is first calculated, showing that the hole states are denser than the electron states. Fourier transforms of the time-resolved energy levels show that the hot carriers couple to both acoustic and optical phonons. At higher temperature, more phonon modes in the high-frequency range participate in the relaxation process due to their increased occupation number. The phonon-assisted hot-carrier relaxation time is predicted using nonadiabatic molecular dynamics, and the results clearly show a temperature-activation behavior. …

Thermal Conductivity Of Bismuth Telluride Nanowire Array-Epoxy Composite, Kalapi G. Biswas, Timothy D. Sands, Baratunde Cola, Xianfan Xu

Birck and NCN Publications

Electrodeposition of nanowire array in porous anodic alumina (PAA) templates combine the performance benefits offered by crystallographic texture control, lattice thermal conductivity suppression through boundary scattering of phonons, elastic relaxation of misfit strain, and scalablity essential for high efficiency thermoelectric devices. The template material, however, can serve as a thermal shunt thereby reducing the effective thermoelectric performance. Here, we demonstrate a process of minimizing the parasitic thermal conduction by replacing the PAA matrix with SU-8 (kappa similar to 0.2 W/m K). We report a reduction in the performance penalty from 27% for Bi2Te3/PAA to similar to 5% for Bi2Te3/SU-8 nanocomposite …

Demonstration Of Quadrature-Squeezed Surface Plasmons In A Gold Waveguide, Alexander Huck, Stephan Smolka, Peter Lodahl, Anders S. Sorensen, Alexandra Boltasseva, Jiri Janousek, Ulrik Andersen

Birck and NCN Publications

We report on the efficient generation, propagation, and reemission of squeezed long-range surface-plasmon polaritons in a gold waveguide. Squeezed light is used to excite the nonclassical surface-plasmon polaritons, and the reemitted quantum state is fully characterized by complete quantum tomographic reconstruction of the density matrix. We find that the plasmon-assisted transmission of nonclassical light in metallic waveguides can be described by a beam splitter relation. This result is explained theoretically.

Performance Analysis Of Statistical Samples Of Graphene Nanoribbon Tunneling Transistors With Line Edge Roughness, Mathieu Luisier, Gerhard Klimeck

Birck and NCN Publications

Using a three-dimensional, atomistic quantum transport simulator based on the tight-binding method, we investigate statistical samples of single-gate graphene nanoribbon (GNR) tunneling field-effect transistors (TFETs) with different line edge roughness probabilities. We find that as the nanoribbon edges become rougher, the device OFF-current drastically increases due to a reduction of the graphene band gap and an enhancement of source-to-drain tunneling leakage through the gate potential barrier. At the same time, the ON-current remains almost constant. This leads to a deterioration of the transistor subthreshold slopes and to unacceptably low ON/OFF current ratios limiting the switching performances of GNR TFETs.

Demonstration Of Quadrature-Squeezed Surface Plasmons In A Gold Waveguide, Alexander Huck, Stephan Smolka, Peter Lodahl, Anders S. Sorensen, Alexandra Boltasseva, Jiri Janousek, Ulrik Andersen

Birck and NCN Publications

We report on the efficient generation, propagation, and reemission of squeezed long-range surface-plasmon polaritons in a gold waveguide. Squeezed light is used to excite the nonclassical surface-plasmon polaritons, and the reemitted quantum state is fully characterized by complete quantum tomographic reconstruction of the density matrix. We find that the plasmon-assisted transmission of nonclassical light in metallic waveguides can be described by a beam splitter relation. This result is explained theoretically.

Why Is Fresh Self-Compacting Concrete Shear Thickening?, Dimitri Feys, Ronny Verhoeven, Geert De Schutter

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Rheological Properties of Fresh Concrete Are Mostly Described by Means of the Bingham Model. for Self-Compacting Concrete, the Bingham Model is Applicable in a Lot of Cases, But Some Authors Report that the Rheological Behavior is Non-Linear. the Apparent Viscosity Increases with Increasing Shear Rate and the SCC Shows Shear Thickening Behavior. Shear Thickening Becomes Important in Operations Occurring at High Shear Rates, Like Mixing and Pumping. in These Cases, Shear Thickening Should Not Be Forgotten in Order to Avoid Breaking of the Mixer, Pump or Pipes. This Paper Will Describe Two Possible Theories for Shear Thickening Behavior of …

Design, Construction And Evaluation Of A Multi Layered Solar Distillation Prototype, Arlen A. Flanagan

BioResource and Agricultural Engineering

Water is arguably the most important resource to any individual; especially in areas of deserts and open oceans where drinkable water suppliers are scarce. The prototype Solar Desalination Unit allows normally undrinkable water to be distilled into a potable source with minimal inputs. The unit’s main power source is focused sunlight to thermally heat water inducing evaporation which is then condensed and collected. While solar desalination has been around for many years, lately more complex designs have been investigated in order to increase yields and efficiency. This paper focuses on the design, construction and testing of a Multi-Plate Solar Desalination …