Engineering Commons^™

Atomistic Study Of Electronic Structure Of Pbse Nanowires, Abhijeet Paul, Gerhard Klimeck

Birck and NCN Publications

Lead Selenide (PbSe) is an attractive ‘IV-VI’ semiconductor material to design optical sensors, lasers and thermoelectric devices. Improved fabrication of PbSe nanowires (NWs) enables the utilization of low dimensional quantum effects. The effect of cross-section size (W) and channel orientation on the bandstructure of PbSe NWs is studied using an 18 band sp3d5 tight-binding theory. The bandgap increases almost with the inverse of the W for all the orientations indicating a weak symmetry dependence. [111] and [110] NWs show higher ballistic conductance for the conduction and valence band compared to [100] NWs due to the significant splitting of the projected …

Starting Cansat – Where To Now?, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs titled "Starting CanSat – Where to Now?" from March 8, 2011.

Polymeric Splint And Rapid-Setting Polyurethane, Lanny Griffin, Dane Robert Jones

Biomedical Engineering

A splint includes a first container capable of being wrapped about an item to be supported and a second container capable of containing a multiple part mixture during a mixing operation. The second container being capable of delivering the mixture into the first container, wherein the mixture hardens to form a support structure. A method for using the splint is also disclosed.

Genomic Library Screens For Genes Involved In N-Butanol Tolerance In Escherichia Coli, Luis Reyes, Maria Almario, Katy Kao

Faculty Publications

Backgroundn-Butanol is a promising emerging biofuel, and recent metabolic engineering efforts have demonstrated the use of several microbial hosts for its production. However, most organisms have very low tolerance to n-butanol (up to 2% (v/v)), limiting the economic viability of this biofuel. The rational engineering of more robust n-butanol production hosts relies upon understanding the mechanisms involved in tolerance. However, the existing knowledge of genes involved in n-butanol tolerance is limited. The goal of this study is therefore to identify E. coli genes that are involved in n-butanol tolerance.Methodology/Principal FindingsUsing a genomic library enrichment strategy, we identified approximately 270 genes …

Xdl-Based Hard Macro Generator, Subhrashankha Ghosh

Theses and Dissertations

In a conventional hardware design flow, the compilation process to create the physical circuit on the FPGA takes a long time. HMFlow is a design flow that reduces the compilation time by using pre-compiled modules called hard macros. HMFlow uses System Generator to create the designs, which are then converted to hard macros. The hard macro creation process takes a long time and a possible solution is a hard macro generator called XdlCoreGen, which is described in this thesis. XdlCoreGen can quickly create fully mapped and placed hard macros using XDL. XDL is a human readable design format that describes …

Effects Of Damköhler Number On Flame Extinction And Reignition In Turbulent Non-Premixed Flames Using Dns, David O. Lignell, Jacqueline H. Chen, Hans A. Schmutz

Faculty Publications

Results from a parametric study of flame extinction and reignition with varying Damköhler number using direct numerical simulation are presented. Three planar, non-premixed ethylene jet flames were simulated at a constant Reynolds number of 5120. The fuel and oxidizer stream compositions were varied to adjust the steady laminar extinction scalar dissipation rate, while maintaining constant flow and geometric conditions. Peak flame extinction varies from approximately 40% to nearly global blowout as the Damköhler number decreases. The degree of extinction significantly affects the development of the jets and the degree of mixing of fuel, oxidizer, and combustion products prior to reignition. …

Polarity Effects In The X-Ray Photoemission Of Zno And Other Wurtzite Semiconductors, M. W. Allen, Dmitry Zemlyanov, G.I.N. Waterhouse, J. B. Metson, T. D. Veal, C. F. Mcconville, S. M. Durbin

Birck and NCN Publications

Significant polarity-related effects were observed in the near-surface atomic composition and valence band electronic structure of ZnO single crystals, investigated by x-ray photoemission spectroscopy using both Al K(alpha) (1486.6 eV) and synchrotron radiation (150 to 1486 eV). In particular, photoemission from the lowest binding energy valence band states was found to be significantly more intense on the Zn-polar face compared to the O-polar face. This is a consistent effect that can be used as a simple, nondestructive indicator of crystallographic polarity in ZnO and other wurtzite semiconductors. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3562308]

Modal Logic And Its Applications, Explained Using Puzzles And Examples, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

1.We shall be concerned, at first, with alethicmodal logic, or modal logic tout court. 2.The starting point, once again, is Aristotle, who was the first to study the relationship between modal statements and their validity. 3.However, the great discussion it enjoyed in the Middle Ages. 4.The official birth date of modal logic is 1921, when Clarence Irving Lewis wrote a famous essay on implication.

Test Case Series 1 (Overview Of Intercalibration Results: A Model Comparison), Thermal Performance Database Team

Ablation Workshop: Code Comparison

Presentation Overview:

• Comparison of model results
• All comparisons (plots) are percent difference from FIAT reference model

Overview Of Roughness And Blowing Effects In Flows Over Ablating Surfaces, Adam Amar, Charles Powars

Ablation Workshop

The scope of this session includes ablation effects on surface roughness and surface roughness effects on ablation. Ablation involves blowing, and so we address blowing including combined roughness and blowing effects. The two distinct types of ablating material surface roughness are defined with examples: 1) roughness related to the material inhomogeneity, and 2) roughness induced by turbulent flow that appears to be unrelated to material inhomogeneties.

Existing approaches for modeling ablative material surface roughness and blowing effects are overviewed. These range from empirical “augmentation factor” correlations to high-fidelity simulations of flow-surface interactions using modern CFD techniques. For models requiring input …

Gsi Modeling Overview: Requirements For Macroscopic Gas/Surface Interaction Coupling To Cfd Codes, Matthew Maclean, Jochen Marschall

Ablation Workshop

An overview is presented of a generalized finite-rate surface chemistry model that has been developed for gas/surface interaction coupling to the Data-Parallel Line-Relaxation (DPLR) code. Species from the gaseous environment are allowed to interact with species adsorbed onto one or more phase of a surface and with one or more phases of a bulk thermal protection system through an arbitrary number of finite-rate reactions. The reactions may include types such as adsorption, desorption, Eley-Rideal recombination, Langmuir-Hinschelwood recombination, partial or total dissociative adsorption, oxidation, reduction, sublimation, or condensation where forward and reverse rates are constrained by thermodynamics. A simple pyrolysis model …

High Enthalpy Ablation Testing At Dlr Cologne, Bunkard Esser, A. Gülhan, U. Koch

Ablation Workshop

Testing thermal protection capabilities of ablative materials is one of the main working areas of DLR’s arc heated facilities LBK in Cologne. Work on this particular topic has been intensified about five years ago with the following major focus points:

• Significant improvement of the facilities testing capabilities with respect to cold wall heat flux rates and stagnation pressure.
• Ablation testing in Martian atmosphere.
• Influence of dust particle erosion on ablation.

Building America Industrialized Housing Partnership (Baihp Ii) Final Report Budget Periods 1-5, April 1, 2006 - November 30, 2010, Florida Solar Energy Center, Robert Abernethy

FSEC Energy Research Center®

This report summarizes the work conducted by the Building America Industrialized Housing Partnership (BAIHP - www.baihp.org) during the final budget period (BP5) of our contract, January 1, 2010 to November 30, 2010. Highlights from the four previous budget periods are included for context.

BAIHP is led by the Florida Solar Energy Center (FSEC) of the University of Central Florida. With over 50 Industry Partners including factory and site builders, work in BP5 was performed in six tasks areas:

• Task 1: Building America System Research Management, Documentation and Technical Support
• Task 2A: Stage G1A: Integrated Solutions for Specific Climate Regions
• Task …

Nitric Oxide Plif Measurements In The Hypersonic Materials Environmental Test System (Hymets), Paul M. Danehy

Ablation Workshop

A nonintrusive laser-based measurement system has been applied for the first time in the HYMETS (Hypersonic Materials Environmental Test System) 400 kW arc-heated wind tunnel at NASA Langley Research Center. Planar laser-induced fluorescence of naturally occurring nitric oxide (NO) has been used to obtain instantaneous flow visualization images, and to make both radial and axial velocity measurements. Results are presented at selected facility run conditions, including some in simulated Earth atmosphere (75% nitrogen, 20% oxygen, 5% argon) and others in simulated Martian atmosphere (71% carbon dioxide, 24% nitrogen, 5% argon), for bulk enthalpies ranging from 6.5 MJ/kg to 18.4 MJ/kg. …

Experimental Data Need For High-Fidelity Material-Response Models, Jean R. Lachaud, Ioana Cozmuta, Nagi N. Mansour

Ablation Workshop

Several high-fidelity material-response models are being developed by the hypersonic community. These models require, in addition to the input parameters traditionally used in the state-of-the-art material-response codes, data not currently available - at least in the open literature. The presentations in the session will describe both state-of-the-art experimental techniques and innovative methods in support of model development and data acquisition for high-fidelity models.

Design Guide For Cold-Formed Steel Purlin Roof Framing Systems, American Iron And Steel Institute (Aisi)

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

"The Design Guide for Cold-Formed Steel Purlin Roof Framing Systems provides information for the designer of single span and continuous multiple span steel purlin-supported roof systems with an emphasis on the design anchorage systems. The Design Guide is based on the American Iron and Steel Institute (AISI) North American Specification for the Design of Cold-Formed Steel Structural Members, 2007 Edition. Where the Specification is silent on design issues, the procedures are based on published references and on the opinions of the authors.

The Design Guide was co-sponsored by the American Iron and Steel Institute (AISI) and the Metal Building …

Development And Delivery Of An Integrated Project-Based Jobsite Management Undergraduate Course, Philip L. Barlow

Construction Management

At universities offering professional degrees, such as construction management, some programs are moving towards and exploring alternative delivery methods for achieving the curriculum's goals and objectives. This article describes an integrated and project-based learning Jobsite Construction Management course being taught at a major university. A course overview describing the various delivery methods used (such as lectures, reading assignments, supplemental materials, guest lecturers, lab assignments, technology, and jobsite visits) is presented. The benefits of vertical and horizontal course integration in a project-based learning environment are emphasized and more fully explained. A class survey was conducted over two quarters to assess the …

Investigation Of The Behavior Of Free-Standing Gabions In Seismic Regions, Amy Ransom

Master's Theses

This thesis investigates the behavior of free-standing gabion walls in areas of mild seismicity. To investigate this behavior, three walls of varying internal cable patterns were constructed at a quarter-scale. These walls were tested with a mass shaker, and mode shapes, tone extractions, and damping ratios were calculated. A modal analysis was conducted using design spectra created from a suite of seven earthquakes from countries bordering Kenya. The corresponding lateral forces to these spectral displacements were found, and the restoring eccentricities from the soil restoring force were backed out through a summation of moments. All analysis was experimentally done due …

Exploring Trade-Offs In Auv Controller Design For Shark Tracking, Louis James Bertsch Iv

Master's Theses

This thesis explores the use of an Autonomous Underwater Vehicle (AUV) to track and pursue a tagged shark through the water. A controller was designed to take bearing and range to the shark tag and then control the AUV to pursue it.

First, the ability of a particle filter to provide an accurate estimation of the location of the shark relative to the AUV is explored. Second, the ability of the AUV to follow the shark's path through the water is shown. This ability allows for localized environmental sampling of the shark's preferred path. Third, various path weightings are used …

Material Weight Station Optimization Senior Project, Douglas Peters, Michael Eng

Industrial Technology and Packaging

The main principle of all industry is that “time is money”. This senior project focuses on reducing operation times for Specialty Silicone Fabricators (SSFab) materials weighing station. Currently SSFab is set up so that multiple operators check the weights of materials. This is done to guarantee the accuracy of the readings and maintain tight quality control. This project will focus on eliminating the need of multiple weight checkers as a way to save time and ultimately save money.

Through detailed research and studies it has been determined that the most appropriate solution to this problem is a weight checking software …

Gauge Repeatability And Reproducibility Study For A Bulge Test Fixture For Corrugated Boxes, Anthony J. Hall

Industrial Technology and Packaging

This senior project evaluates the measurement variation within a corrugated container bulge tester by utilizing a gauge repeatability and reproducibility study. Bulge is a type of deformation containers experience when subject to compressive forces such as stacking or internal forces due to under- and over-packaging. Both compressive and internal forces can accelerate the failure of a container by causing panels to flex and flutes to buckle, compromising structural integrity. Additionally, variable environmental conditions such as temperature and humidity can magnify the effect bulge has on a container, speeding up the failure rate of a container.

Acuta Enews March 2011 Vol. 40, No. 3

ACUTA Newsletters

ln This lssue

Meet the Board for 2011-12

Tech Talk: Take Two Tablets and Catt Me in the Morning.......... Kevin Tanzillo, Dux PR

Free Webinars Coming Soon to ACUTA

Learn More about UC, Voice Trends, the Cloud, and More from Your Desktop

From ACUTA Headquarters: Member Years of Service ,Jeri A. Semer, CAE, Executive Dir

Board Report......... George Denbow, univ. of Texas, Austin

New to ICT or Not, ACUTA Members Are All Busy!........... Young Professionals Subcommittee

lT's Funny!

lnfo Links ........... .. Randy Hayes, Univ' of Northern lowa

ACUTA 2011 Event Calendar

Welcome New Members

Check lt Out: Press Releases...Job …

Single-Beam Holographic Tomography Creates Images In Three Dimensions, George Nehmetallah, Partha P. Banerjee, Nickolai Kukhtarev

Electrical and Computer Engineering Faculty Publications

In digital holography (DH), the interference between light scattered from an object and a reference wave is recorded using a CCD camera. DH has various advantages over analog holography: no film processing is needed, reconstruction is performed using numerical methods, and no further experimental setup is necessary. However, one of the disadvantages of DH is that current CCDs have a resolution of approximately 1,000 lines/mm, which is less than that of photographic film.

Anisotropic Electrical Properties Of Nanostructured Metallic Thin Films, Mo Ahoujja, Piyush Shah, Andrew Saragan, Said Elhamri, Elena A. Guliants

Electrical and Computer Engineering Faculty Publications

High surface area, porous, metallic (Ti, Cr) nanorod thin ¯lms with columnar microstructure can be deposited using conventional physical vapor deposition technique of E-beam evaporation. The technique relies on the physical vapor deposition onto a static substrate oriented in a position where °ux from the source material (Ti, Cr) arrives at oblique angle. The adatoms provides geometrical shadowing which results in growth of nanorod columns in the direction of vapor source. Deposition conditions such as angle of the incoming vapor °ux, substrate temperature, surface di®usion etc. have strong in°uence on the shape and arrangement of the columnar thin ¯lms. In …

Optimizing Trajectories For Unmanned Aerial Vehicles (Uavs) Patrolling The Border, Chris Kiekintveld, Vladik Kreinovich, Octavio Lerma

Departmental Technical Reports (CS)

Estimating Covariance For Privacy Case Under Interval (And Fuzzy) Uncertainty, Ali Jalal-Kamali, Vladik Kreinovich, Luc Longpre

Departmental Technical Reports (CS)

Knowledge Annotations In Scientific Workflows: An Implementation In Kepler, Aida Gandara, George Chin Jr., Paulo Pinheiro Da Silva, Signe White, Chandrika Sivaramakrishnan, Terence Critchlow

Departmental Technical Reports (CS)

Scientific research products are the result of long-term collaborations between teams. Scientific workflows are capable of helping scientists in many ways including collecting information about how research was conducted (e.g., scientific workflow tools often collect and manage information about datasets used and data transformations). However, knowledge about why data was collected is rarely documented in scientific workflows. In this paper we describe a prototype system built to support the collection of scientific expertise that influences scientific analysis. Through evaluating a scientific research effort underway at the Pacific Northwest National Laboratory, we identified features that would most benefit PNNL scientists in …

Department Of Biological Systems Engineering Newsletter, Volume 7, Number 1, March 2011

BSE Department Magazine

No abstract provided.

Superlattice Ultrasonic Generation, Thomas E. Wilson, M. Oehme, E. Kasper, H-J. L. Gossmann

Physics Faculty Research

We report the first experimental evidence for the resonant excitation of coherent high-frequency acoustic phonons in semiconducting doping superstructures by far-infrared laser radiation. After a grating-coupled delta-doped silicon doping superlattice is illuminated with ~1 kW/mm² nanosecond-pulsed 246 GHz laser radiation, a delayed nanosecond pulse is detected by a superconducting bolometer at a time corresponding to the appropriate time-of-flight for ballistic longitudinal acoustic phonons across the (100) silicon substrate. The absorbed phonon power density in the microbolometer is observed to be ~10 μW/mm², in agreement with theory. The phonon pulse duration also matches the laser pulse duration. The …

Topscholar® Creating Opportunities [2011 Brochure], Connie Foster, Jennifer Wilson

TopSCHOLAR® Presentations and Reports

No abstract provided.