Engineering Commons^™

Disasters And Energy Security Management, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

In the past, natural disasters, such as hurricanes, floods, tornados, and earthquakes, were one of our major concern. Now, terrorist events are becoming more common and more destructive. Whether, natural or man made, a disaster can happen at any time, often with little or no advance warning. A disaster can leave many people without adequate medical services, potable water, electrical service and communications for long periods of time. They can be as destructive as Hurricane Mitch leaving several hundred-thousand people homeless or as minor as an afternoon thunderstorm knocking down local power lines to your home. Not only can lives …

A Closed-Form Dynamic Model Of The Compliant Constant-Force Mechanism Using The Pseudo-Rigid-Body Model, Cameron Boyle

Theses and Dissertations

A mathematical dynamic model is derived for the compliant constant-force mechanism, based on the pseudo-rigid-body model simplification of the device. The compliant constant-force mechanism is a slider mechanism incorporating large-deflection beams, which outputs near-constant-force across the range of its designed deflection. The equation of motion is successfully validated with empirical data from five separate mechanisms, comprising two configurations of compliant constant-force mechanism. The dynamic model is cast in generalized form to represent all possible configurations of compliant constant-force mechanism. Deriving the dynamic equation from the pseudo-rigid-body model is useful because every configuration is represented by the same model, so a …

Double-Scaled Potential Profile In A Group-Iii Nitride Alloy Revealed By Monte Carlo Simulation Of Exciton Hopping, K. Kazlauskas, G. Tamulaitis, A. Zukauskas, M. A. Khan, J. W. Yang, J. Zhang, Grigory Simin, M. S. Shur, R. Gaska

Faculty Publications

The temperature dependences of the peak position and width of the photoluminescence band in Al_0.1In_0.01Ga_0.89N layers were explained by Monte Carlo simulation of exciton localization and hopping. The introduction of a doubled-scaled potential profile due to inhomogeneous distribution of indium allowed obtaining a good quantitative fit of the experimental data. Hopping of excitons was assumed to occur through localized states distributed on a 16 meV energy scale within the In-rich clusters with the average energy in these clusters dispersed on a larger (42 meV) scale.

Predicting Drag Polars For Micro Air Vehicles, Mark Elden Luke

Theses and Dissertations

Drag polars for three Micro Air Vehicles (MAVs) were measured at Reynolds numbers of 70,000, 50,000, 30,000, and 10,000 and compared to predictions generated using the classical approach. The MAVs tested had different configurations and aspect ratios varying from 1.2 to 1.6 and ratios of wetted surface area to planform area from 2.6 to 3.9.

A force balance was used to measure the lift and drag on the MAVs at angles of attack ranging from -5 degrees (or -10 degrees) to 10 degrees. The force balance allowed the MAVs to rotate in the pitching axis. The MAV angle of attack …

Steel Stud Brick Veneer Design Guide, American Iron And Steel Institute

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

The following Design Guide has been developed under the direction of the American Iron and Steel Institute Committee on Specifications for the Design of Cold- Formed Steel Structural Members. The development of the Guide was sponsored by the American Iron and Steel Institute. The AISI Committee on Specifications wishes to acknowledge and expresses gratitude to Mr. Thomas Trestain of T. W. J. Trestain Structural Engineering who was the author of this Guide.

With anticipated improvements in understanding of the behavior of cold-formed steel and the continuing development of new technology, this material might become dated. It is possible that AISI …

Soil Salinity Accumulation In Orchards With Drip And Micro-Spray Irrigation In Arid Areas Of California, Charles M. Burt, Brett Isbell

BioResource and Agricultural Engineering

A soil salinity accumulation study was conducted by ITRC during the summer of 2002 to examine the long-term impact of drip and micro irrigation on salinity build-up in orchards, focusing on the salinity concentration pattern across a soil profile. This study assessed the current level of salinity accumulation in orchards irrigated with drip/micro systems and provided information to support recommendations on the most effective and efficient leaching techniques.

There is a concern that soil salinity accumulation in orchards, which comprise large acreages in the Central Valley of California, will eventually require reclamation leaching. Not only would this consume large quantities …

Reclamation Leaching For Salinity Buildup Under Drip/Micro Irrigation Of Trees, Charles M. Burt, Brett Isbell

BioResource and Agricultural Engineering

ITRC conducted a reclamation leaching experiment in a pistachio orchard in order to quantify the leaching water required to remove salts from the effective root zone of trees. This experiment tested a new reclamation leaching technique - multiple lines of low-flow drip tape were used to apply water to the area of salinity accumulation along a tree row.

Soil Salinity Accumalation In Orchards With Drip And Micro-Spray Irrigation In Arid Areas Of California, Charles M. Burt, Brett Isbell

BioResource and Agricultural Engineering

A soil salinity accumulation study was conducted to examine the long-term impact of drip and micro irrigation on salinity build-up in orchards, focusing on the salinity concentration pattern across a soil profile. The study assessed the current level of salinity accumulation in orchards irrigated with drip/micro systems and provided information to support recommendations on the most effective and efficient leaching techniques.

Long-Term Salinity Buildup On Drip/Micro Irrigated Trees In California, Charles M. Burt, Brett Isbell, Lisa Burt

BioResource and Agricultural Engineering

The Irrigation Training and Research Center (ITRC) of Cal Poly State University, San Luis Obispo, CA, hypothesized that there is salinity accumulation in the root zone of tree crops that have been irrigated with drip or micro-spray irrigation systems, located in arid and semi-arid regions. Therefore, a study was conducted by ITRC during the summer of 2002 to examine the long-term impact of drip and micro irrigation on salinity accumulation in orchards, focusing on the salinity concentration pattern across a soil profile. The project also provided information to support recommendations on the most effective and efficient leaching techniques.

During the …

Coordinate Metrology For Machine Tools, Brian Warren

Electronic Dissertations and Theses

This thesis is concerned with Coordinate Metrology for Machine Tools. The contributions of the thesis are of two criteria. First, by making use of techniques from available software to determine geometry characteristic performance of a Mazak Quick Turn 20 Slant-Bed Lathe, and we determine theory for categorizing typical lathe evaluation; second, we extend this powerful geometric process to verification formulation of the error estimates by utilizing coordinate metrology notations contained in Brown & Sharpe's "Coordinate Metrology" standards and develop evaluation techniques for verifying machine tool path error estimation based on important observations that machined part features have a deviation from …

Acuta Enews November 2003, Vol 32, No. 11

ACUTA Newsletters

In This Issue

From ACUTA Headquarters................................. Jeri A. Semer, CAE, Executive Director

Tech Talk................................................. Kevin Tanzillo, Dux Public Relations

No Spam for Me, Please

VolP Design Recommendations................................. John Garrison, Alcate

DC Update....................... Whitney Johnson, Retired, Northern Michigan Univ.

Thanks to Exhibitors for '03

ACUTA Board Report................................... Carmine Piscopo, Providence College

Welcome New Members

ACUTA: Have You Shopped the eStore Lately?

Complying With Florida's Green Land Development Standard: Case Studies And Lessons Learned, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

The Florida Green Building Coalition, Inc. (FGBC), developed a standard for green land development. It is the first voluntary, non-government standard of its kind to target an entire state. Other groups have created development standards that apply to just a local Home Building Associations (HBA) or a local jurisdiction. The U.S. Green Building Council (USGBC) is beginning a Leadership in Energy & Environmental Design (LEEDTM) for neighborhoods. To comply with Florida's standard, a developer has to earn sufficient points among six categories:

1. Protect Ecosystems and Conserve Natural Resources: for example, surveys, conservation areas, wildlife corridors, wetland preservation and management
2. Circulation: …

The Benefits Of Using Window Shades, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

Windows play an important aesthetic role in our daily lives. At the same time, windows typically add significantly to the cost of heating and cooling buildings. After reviewing the physical principles by which windows add heat to buildings and the standard techniques employed to reduce unwanted heating, this paper focuses on one type of device which is readily available, inexpensive to purchase and operate, and capable of being adjusted to changing conditions on even an hourly basis. The device is the common window shade. This paper develops a simple, but realistic, model for computing the advantage of using reflective interior …

Effects Of Intermetallic Morphology At The Metallic Particle/Solder Interface On Mechanical Properties Of Sn-Ag-Based Solder Joints, H. Rhee, F. Guo, J. G. Lee, Katherine C. Chen, K. N. Subramanian

Materials Engineering

Mechanical incorporation of metallic particles in the Sn-Ag-based solder resulted in various intermetallic compound (IMC) morphologies around these particles during reflow. Unlike with the Ni particles, the IMCs formed around Cu and Ag particles are relatively insensitive to reflow profiles employed. The IMC formed around the Ni particles ranges from “sunflower” morphology to “blocky” morphology with increasing time and temperature above liquidus during the heating part of the reflow profile. Mechanical properties, such as simple shear strength and creep behavior, of these composite solders were affected by the IMC morphologies in the composite solders investigated. Sunflower-shaped IMC formed around an …

Salinity Patterns: On Row Crops Under Subsurface Drip Irrigation (Sdi) On The Westside Of The San Joaquin Valley Of California, Charles M. Burt, Othman Al-Amoudi, Alejandro Paolini

BioResource and Agricultural Engineering

The objectives of this study were to identify if there was detrimental salinity buildup in the upper layers of soil caused by the usage of SDI on row crops, identify the extent of any detrimental salinity buildup, and identify successful and/or essential practices used by farmers who use SDI.

Flight Physician - November, 2003, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A twenty-four page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Screw Dislocation Interacting With Twin Interfacial Edge Cracks Between Two Bonded Dissimilar Piezoelectric Strips, Xiangfa Wu, Yuris A. Dzenis, Tian-You Fan

Department of Engineering Mechanics: Faculty Publications

This paper is concerned with the electroelastic potentials and the fracture parameters of a twin-edge-cracked piezoelectric bimaterial strip with a screw dislocation. By means of conformal mapping technique and the known dislocation solution, the antiplane displacement and inplane electric potentials are obtained in closed-form. The intensity factors and the energy release rate are extracted explicitly. In some limiting cases, the present solutions cover those in the literature.

A Macrokinetic Study Of The High-Temperature Solid-Phase Titanium-Carbon Reaction, Julia Y. Kostagorva, Hendrik J. Viljoen, Alexander S. Shteinberg

Papers in Reaction Kinetics

An experimental method, electro thermal explosion (ETE), is used to measure the macro kinetic parameters of the high-temperature titanium/carbon reaction. Different stages of the reaction have been identified, but the focus of this study is on the reaction between solid titanium and solid carbon, i.e., prior to the melting of titanium. The reaction has high activation energy, and an electric current is used to heat the cylindrically shaped sample to a specified temperature. The current is shut off at a temperature below the melting point of titanium; any further temperature rise is only due to reaction. The output of the …

Minimality Of Solution Update In Conflict Resolution: An Application Of Revision Programming To Von Neumann-Morgenstern Approach, Inna Pivkina, Vladik Kreinovich

Departmental Technical Reports (CS)

In a 1944 book that started game theory (and mathematical approach to conflict resolution), von Neumann and Morgenstern proposed the notion of a solution. When the situation changes, the old solution is often no longer a solution, so it needs to be updated. In practical applications, it is usually desirable to keep the solution change "minimal" in some reasonable sense. We show that for a seemingly straightforward formalization of this minimality, checking whether a change is minimal is NP-hard. We also show that by representing the notion of a solution as a collection of revision rules, we can produce a …

Turning An Articulated Truck On A Spreadsheet, Jim Mcgovern

Articles

This paper describes how a standard office spreadsheet application was used to set up an engineering model for the simulation and analysis of the turning of articulated trucks

Task Allocation Via Multi-Agent Coalition Formation: Taxonomy, Algorithms And Complexity, Hoong Chuin Lau, L. Zhang

Research Collection School Of Computing and Information Systems

Coalition formation has become a key topic in multiagent research. In this paper, we propose a preliminary classification for the coalition formation problem based on three driving factors (demands, resources and profit objectives). We divide our analysis into 5 cases. For each case, we present algorithms and complexity results. We anticipate that with future research, this classification can be extended in similar fashion to the comprehensive classification for the job scheduling problem.

Design And Characterization Of Null Convention Self-Timed Multipliers, Satish K. Bandapati, Scott C. Smith, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

Self-timed multipliers, designed using the delay-insensitive null convention logic (NCL) paradigm, were analyzed. NCL require less power, generate less noise, produce less electromagnetic interference, and allow easier reuse of components. Simulation results show a large variance in circuit performance in terms of power, area, and speed. NCL paradigm also represent bit-serial, iterative, and fully parallel multiplication architectures. They reduce the effort required to ensure correct operation under all timing scenarios, compared to equivalent synchronous designs.

An Improved Simulation Model For Spaceborne Scatterometer Measurements, David G. Long, Peter K. Yoho

Faculty Publications

Development of scatterometer designs and applications requires extensive data simulation. The advancing capabilities of instruments motivates our proposal for an improved simulation model for noisy scatterometer measurements. Previous simulation models do not separately account for the two forms of random variation - signal fading and additive noise - which affect scatterometer measurements. The proposed model is able to generate data that are statistically equivalent (in a mean and variance sense) to actual instrument measurements by accounting for both variations, while maintaining ease of implementation. The model is particularly adept at handling design tradeoffs related to signal-to-noise ratios by appropriately separating …

Yieldlike Constitutive Transition In Shear Flow Of Entangled Polymeric Fluids, Prashant Tapadia, Shi-Qing Wang

College of Polymer Science and Polymer Engineering

We describe an unexpected constitutive transition in entangled polymer solutions. At and beyond a critical stress, the initial spatially homogeneous and well-entangled sample transforms from its entangled (coiled) state into a fully disentangled (stretched) state over a period during which the resulting shear rate increases in a spatially inhomogeneous fashion. In the mode of controlled shear rate, the sample exhibits a stress plateau over three decades. Flow birefringence and normal stress observations unravel additional features of these flow phenomena.

Converting Plant Biomass To Fuels And Commodity Chemicals In South Africa: A Third Chapter?, L R. Lynd, H H Von Blottnitz, B Tait, J De Boer, I S. Pretorius, K Rumbold, W H. Van Zyl

Dartmouth Scholarship

There have been two distinct chapters in the history of converting cellulosic biomass to fuels and commodity chemicals in South Africa. The first chapter, fromthe late 1970s to the early 1990s, involved some of the most active research and development efforts of their kind anywhere in the world. Thereafter, during the second chapter, there has been very little activity in the field in South Africa while there has been an unprecedented awakening to the potential of biomass conversion elsewhere. This paper considers the rationale and possible benefits of a potential third chapter based on a revitalized effort on biomass conversion …

Pavement Evaluation, I-265 Jefferson County Mp 15.0-19.0, Brad Rister, R. Clark Graves, David L. Allen

Kentucky Transportation Center Research Report

The Transportation Center conducted a field survey of the pavement conditions located on I-265 in Jefferson County from MP 15.17 to 18.34, in both the eastbound and westbound directions. The existing pavement structure consists of 10″ of PCC pavement and 6″ of DGA. The field survey involved testing the 3.17 mile segment with a Falling Weight Deflectometer (FWD), Ground Penetrating Radar (GPR), and taking core samples of the pavement structure.

Tongue Movements In Feeding And Speech, Karen M. Hiiemae, Jeffrey B. Palmer

Biomedical and Chemical Engineering - All Scholarship

The position of the tongue relative to the upper and lower jaws is regulated in part by the position of the hyoid bone, which, with the anterior and posterior suprahyoid muscles, controls the angulation and length of the floor of the mouth on which the tongue body 'rides'. The instantaneous shape of the tongue is controlled by the 'extrinsic muscles ' acting in concert with the 'intrinsic ' muscles. Recent anatomical research in non-human mammals has shown that the intrinsic muscles can best be regarded as a 'laminated segmental system ' with tightly packed layers of the 'transverse', 'longitudinal', and …

Temperature Control Of A Solid Substrate Cultivation Deep - Bed Reactor Using An Internal Heat Exchanger, Mari S. Chinn, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

The solid substrate cultivation (SSC) process is often limited by rapid increases in temperature as a result of metabolic activity and poor heat transfer properties of the solid substrate. High temperatures can adversely affect microbial growth and product formation. Reduction of substrate temperatures is important for improved productivity, yet effective and efficient control of heat transfer in a deep-bed SSC reactor has proven difficult. An internal cooling water coil was incorporated into a deep-bed reactor system and evaluated for its ability to reduce substrate temperature. Three operating treatments were investigated: cooling water circulation whenever the center bed temperature was above …

Melanoma And Seborrheic Keratosis Differentiation Using Texture Features, Srinivas V. Deshabhoina, Scott E. Umbaugh, William V. Stoecker, Randy Hays Moss, Subhashini K. Srinivasan

Chemistry Faculty Research & Creative Works

Purpose: To explore texture features in two-dimensional images to differentiate seborrheic keratosis from melanoma.

Methods: A systematic approach to consistent classification of skin tumors is described. Texture features, based on the second-order histogram, were used to identify the features or a combination of features that could consistently differentiate a malignant skin tumor (melanoma) from a benign one (seborrheic keratosis). Two hundred and seventy-one skin tumor images were separated into training and test sets for accuracy and consistency. Automatic induction was applied to generate classification rules. Data analysis and modeling tools were used to gain further insight into the feature space. …

Steel Bridge System With Delayed Composite Action, Atorod Azizinamini, Aaron Jon Yakel

Nebraska Department of Transportation: Research Reports

No abstract provided.