Engineering Commons^™

Detecting Stress And Fatigue Cracks, Christian J. Huber, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Discoveries in using open ended rectangular waveguides for microwave surface crack detection and sizing have generated interest. The foundation, potential, advantages and disadvantages of this methodology, developed at the Applied Microwave Nondestructive Testing Laboratory in the Electrical Engineering Department at Colorado State University, are discussed. Microwave techniques in general and this particular approach offer certain unique advantages that can advance the state of the art of fatigue/surface crack detection. The basic features and capabilities of this technique have been theoretically and experimentally investigated these past few years. However, more developmental work is needed to bring this technique from the laboratory …

The Oligonucleotide Probe Database, Elizabeth Wheeler Alm, Daniel B. Oerther, N. Larsen, David A. Stahl, Lutgarde M. Raskin

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Bs News

Building Services Engineering

No abstract provided.

Modeling A High-Efficiency Ozone Injection Contactor, L. Bernard Garrett Jr.

Civil & Environmental Engineering Theses & Dissertations

Significant research over the last several years has focused on applying modeling equations for estimating design parameters of ozone contactors. Much of this research has focused on fine bubble diffusers, which are the more widely used injection system for ozone contactors in the U.S. A recently developed design incorporates a new ozone injection system called a sidestream venturi injector (SVI) which is used with a co-current downflow column to achieve very high ozone mass transfer efficiencies. A pilot study conducted at the Harwood's Mill water treatment plant in Newport News, Virginia, from June to December 1993 demonstrated the high mass …

An Empirical Comparison Of Networks And Routing Strategies For Parallel Computation, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

This paper compares message routing capabilities of important networks proposed for general-purpose parallel computing. All the networks have been proven to have some type of universality property, i.e., an ability to simulate other networks of comparable cost with modest slowdown, using appropriate cost and communication models. But in this paper we seek an empirical comparison of communication capability under typical direct use rather than an analysis of worst-case results for simulating message traffic of another network.

A Continuous Process For The Conversion Of Vegetable Oils Into Biodiesel, Hossein Noureddini, D Harkey, V Medikonduru

Papers in Biomaterials

Over the last few years fatty acid methyl esters have assumed importance as research has intensified on the utilization of vegetable oils and animal fats derivatives from liquid fuels (better known as biodiesel).Traditional batch processing has been an still is the most widely used process for this coversion. New and more efficient processing schemes. for large scale production of biodiesel for fuelfile1 purposes, is a. key for commercialization of biodiesel. In this, study a continuous process for the transesterification of triglycerides to methyl esters was investigated. This process is based a combined high shear and motionless reactor system. The experimental …

Nlo Waveguide "And" Switch And Method Therefor, John J. Kester, Iyad A. Dajani, Peter M. Ranon, Thomas G. Alley

AFIT Patents

Method and apparatus are provided for NLO switching by first providing a phase-matched SHG grating which outputs a reinforced SHG beam only when two input beams of frequency (ω) are present in two modes of such wg. The so encoded NLO switch is operated by directing at least two input pulsed laser beams of frequency (ω) into the two modes of the wg to generate a reinforced pulsed output SHG beam and output same from the wg in an NLO switching process. The two input beams desirably have a separate pulse train and the spatial and temporal overlap of the …

Effective Doses Of Recombinant Human Bone Morphogenetic Protein-2 In Experimental Spinal Fusion, Harvinder Sandhu, Linda E.A. Kanim, J. Michael Kabo, Jeffrey M. Toth, Erik N. Zeegen, David Liu, Rick B. Delamarter, Edgar G. Dawson

Biomedical Engineering Faculty Research and Publications

Study Design

Nineteen dogs underwent L4-L5 intertransverse process fusions with either 58 μg, 115 μg, 230 μg, 460 μg, or 920 μg of recombinant human bone morphogenetic protein-2 carried by a polylactic acid polymer. A previous study (12 dogs) compared 2300 μg of recombinant human bone morphogenetic protein-2, autogenous iliac bone, and carrier alone in this model. All fusions subsequently were compared.

Objectives

To characterize the dose-response relationship of recombinant human bone morphogenetic protein-2 in a spinal fusion model.

Summary of Background Data

Recombinant osteoinductive morphogens, such as recombinant human bone morphogenetic protein-2, are effective in vertebrate diaphyseal defect and …

Microwave Telemetry For Sensing Conditions In Enclosed Rotating And/Or Reciprocating Machinery, Richard L. Campbell, Douglas B. Brumm, Carl L. Anderson, Glen L. Barna

Michigan Tech Patents

An apparatus for measuring the pressure within the torque converter of an automatic transmission. The apparatus includes a sensor to sense the interior pressure of the torque converter and generate an electrical signal representative of that pressure. That signal is converted to microwave energy which is radiated into the interior of the torque converter housing from a microwave transmitter located within the torque converter. Receiving microwave antennae exposed to the housing interior receive the microwaves and transmit an electrical signal corresponding to the microwave energy to a remote readout external of the torque converter. The receiving antenna are preferably in …

History Of Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, earthquakes, and other disasters can happen any place, any time. Major disasters destroy homes and businesses, and leave many people without adequate medical services, portable water, electrical service and communications. In response to the need for electrical service, solar energy offers a source of quite, safe, pollution-free power. Over the last few years, photovoltaic (solar electricity) power systems have provided energy for various disaster all over the country. Photovoltaics (PV) have been used to power vaccine refrigerators, medical equipment, lighting, radios, fans, communications, traffic devices and other electrical equipment. Previously, photovoltaics have supplied emergency power for Hurricane …

Review Of: Ike Jeanes, Forecast And Solution - A Trilogy For Everyone Grappling With The Nuclear (Pocahontas Press 1996), Drew Schaefer

RISK: Health, Safety & Environment (1990-2002)

Review of the book: Ike Jeanes, Forecast and Solution - A Trilogy for Everyone Grappling with the Nuclear (Pocahontas Press 1996). Addenda, appendix, figures, front matter, notes, references, tables. ISBN 0-936015-62-4 [800 pp. Cloth $32.00; paper $25.00. P.O. Drawer F, Blacksburg VA 24063-1020.]

Risk Criteria For Approving Or Rejecting Field Tests Of High-Performance Weapons, Shaul Feller, Michael Maharik

RISK: Health, Safety & Environment (1990-2002)

Because details are classified and participation by affected populations is limited, military test ranges impose difficult challenges on those responsible for their safety. Here, the authors catalog some of those challenges and suggest ways to address them.

Integrating Multidisciplinary Design In An Undergraduate Curriculum, Russell M. Cummings, H. Jo Anne Freeman

Aerospace Engineering

Multidisciplinary design and analysis has become the normal mode of operation within most aerospace companies, but the impact of these changes have largely not been reflected at many universities. In an effort to determine if the emergence of multidisciplinary design concepts should influence engineering curricula, NASA has asked several universities (Virginia Tech, Georgia Tech, Clemson, BYU, and Cal Poly) to investigate the practicality of introducing the concepts within their undergraduate curricula. A multidisciplinary team of faculty, students, and industry partners evaluated the aeronautical engineering curriculum at Cal Poly. A variety of ways were found to introduce multidisciplinary themes into the …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 12, Number 7, September 1996, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Behavior Of A Hypersonic Nozzle Using Finite Rate Chemistry, Guillermo Jose Hernandez Paul

Master's Theses - Daytona Beach

This study is concerned with the investigation of the behavior of a hypersonic nozzle with finite rate chemistry. First, equations describing steady one dimensional flow through a nozzle are presented. Solution methodologies for frozen, equilibrium and detailed chemistry flow are then discussed. A hydrogen-air chemical reaction mechanism, which is made up of fourteen different chemical species, and forty nine chemical reactions is used in this investigation for obtaining detailed chemistry flow solutions. The investigation also performs a sensitivity analysis on the reaction mechanism. Results from this may be used to eliminate a particular reaction from the chemical reaction mechanism that …

Acuta Enews September 1996, Vol. 25, No. 9

ACUTA Newsletters

In This Issue

From the President

New Legislation

User Group Reports

Changes Come to Campus Directories

From ACUTA Headquarters

Affinity Purification Of Biologically Active Andinactive Forms Of Recombinant Human Protein C Produced In Porcine Mammary Gland, Kevin E. Van Cott, Barry Williams Department Of Chemical Engineering,Virginia Tech University, Blacksburg, Va 24061, Usa, William H. Velander, Francis C. Gwazdauskas, Tim Lee Jerome Holland Laboratory, American Red Cross, Rockville, Md 20855, Usa, Henryk Lubon, William N. Drohan

Papers in Biotechnology

Recombinant human protein C (rhPC) secreted in the milk of transgenic pigs was studied. 'Ikansgenes having different regulatory elements of the murine milk protein, whey acidic protein, were used with cDNA and genomic human protein C (hPC) DNA sequences to obtain lower and higher expressing animals. The cDNA pigs had a range of expression of about 0.1-0.5 g/l milk. Two different genomic hPC pig lines have expressed 0.3 and 1-2 g/l, respectively. The rhPC was first purified at yields greater than 60 per cent using a monoclonal antibody (mAb) to the activation site on the heavy chain of hPC. Subsequent …

Real-Time Optically Processed Face Recognition System Based On Arbitrary Moiré Contours, Rafael A. Andrade, Bernard R. Gilbert, Donald W. Dawson, Chris L. Hart, Samuel Peter Kozaitis, Joel H. Blatt

Electrical Engineering and Computer Science Faculty Publications

We demonstrate a hybrid electronic-optical real-time system that performs 3-D face recognition. We constructed custom reference gratings that formed a desired moire pattern when mixed with images of structurally illuminated faces. The moiré patterns could be in any form such as, equal depth contours, error maps, or any arbitrary pattern. We demonstrate video methods to generate such error maps in real time, thus developing a real-time automated face recognition system based on the optical processing of arbitrary moiré contours. We chose the moiré pattern to be in the form of a Fresnel zone plate, which is displayed on a liquid …

Improving The Performance Of Cellular Manufacturing By A Dynamic Part Assignment Approach, Hamid Seifoddini, Manocher Djassemi

Industrial Technology and Packaging

In this paper, a simple dynamic part assignment (DPA) procedure is introduced and its effects on the performance of cellular manufacturing systems is evaluated. In this procedure rerouting of parts among machine cells is allowed for better machine utilization. Three data sets are used to compare the performance of manufacturing systems under job shop and cellular manufacturing when DPA is employed. The results of simulation runs indicate that the proposed DPA method improves the performance of cellular manufacturing significantly by reducing the congestion in machine cells with long waiting lines.

Measurement And Analysis Of Oxygen/Nitrogen/5a-Zeolite Adsorption Equilibria For Air Separation, Orhan Talu, Jianmin Li, Ravi Kumar, Paul M. Mathias, J. Douglas Moyer Jr, Joan M. Schork

Chemical & Biomedical Engineering Faculty Publications

Multicomponent adsorption equilibrium data are essential for the reliable design of processes and equipment for gas separation by adsorption. We discuss techniques for the measurement and analysis of multicomponent adsorption equilibrium data, and present a comprehensive set of equilibrium data for the adsorption of oxygen and nitrogen on 5A-zeolite.

Chemcial Vapor Deposition Precursor Chemistry. 5. The Photolytic Laser Deposition Of Aluminum Thin Films By Chemical Vapor Deposition, John A. Glass, Seong-Don Hwang, Saswati Datta, Brian W. Robertson, James T. Spencer

Department of Mechanical and Materials Engineering: Faculty Publications

Thin films of very high purity aluminum were formed from the laser photolysis of trimethylamine alane (TMAA) using both ultraviolet (pulsed nitrogen) and visible (argon ion) laser irradiation on a variety of substrates including gold. Si (111), GaAs (110) and Teflon (PTFE). At thicknesses of up to 1 μm, nearly linear growth rates of 377 Ås^-1 and 112 Ås^-1 were observed. The formation of volatile species formed during the deposition of aluminum from TMAA was investigated by quadrupole mass spectrometry (QMS) of the reactant gas stream. The highest intensity post-deposition mass fragments were observed at m/z 58, …

Electromagnetic Scattering From Semi-Infinite Planar Arrays, Peter J. Collins

Theses and Dissertations

A hybrid method of moments (MM) based numerical model for the electromagnetic scattering from large finite by infinite planar slot arrays is developed. The method incorporates the novel concept of a physical basis function (PBF) to dramatically reduce the number of required unknowns. The model can represent a finite number of slot columns with slots oriented along the infinite axis, surrounded by an arbitrary number of coplanar dielectric slabs. Each slot column can be loaded with a complex impedance, allowing one to tailor the edge currents to provide a desired echo width pattern. The surface equivalence theorem is used to …

Maximum Likelihood Estimation Of Exponentials In Unknown Colored Noise For Target Identification In Synthetic Aperture Radar Images, Matthew P. Pepin

Theses and Dissertations

This dissertation develops techniques for estimating exponential signals in unknown colored noise. The Maximum Likelihood (ML) estimators of the exponential parameters are developed. Techniques are developed for one and two dimensional exponentials, for both the deterministic and stochastic ML model. The techniques are applied to Synthetic Aperture Radar (SAR) data whose point scatterers are modeled as damped exponentials. These estimated scatterer locations (exponentials frequencies) are potential features for model-based target recognition. The estimators developed in this dissertation may be applied with any parametrically modeled noise having a zero mean and a consistent estimator of the noise covariance matrix. ML techniques …

Numerical Analysis Of Two And Three Dimensional Recessed Flame Holders For Scramjet Applications, Douglas L. Davis

Theses and Dissertations

This study investigated the flame holding properties of recessed cavities in supersonic flow using numerical analysis techniques. A simplified analytical model indicated that an important property for flame holding was the lower residence time. Several chemical kinetic rate models for hydrogen and hydrocarbon combustion were compared. The perfectly stirred reactor model also indicated that trace species diffusion should increase flame spreading rate, and that heat loss reduces flame holding limits. After nonreacting calibration, two-dimensional simulations confirmed the perfectly stirred reactor results for blowout limits. Also, the effect of trace species diffusion on flame spreading was shown to be negligible, and …

Development And Analysis Of A Dual-Role Fighter Deployment Footprint Logistics Planning Equation, Stanley E. Griffis, Joseph D. Martin

Theses and Dissertations

This research investigated the deployment footprint of a developing dual-role fighter, the Joint Strike Fighter (JSF). This thesis documents the creation of a point estimate linear equation and a spreadsheet model for deployment footprint analysis and provides three example applications of the spreadsheet model for the JSF. The development of the model focused towards direct application in the JSF acquisition process, however, this research also serves as a proof of concept for modeling any future weapon system's deployment footprint. The developed spreadsheet model allows the model manipulator to select a baseline weapon system then alter the various components which make …

An Analysis Of Air Mobility Express Requirements Operating Within A Lean Logistics Wartime Environment, Jennifer A. Bollinger, Kellie L. Davila-Martinez

Theses and Dissertations

Lean Logistics was developed in response to budget cuts, force reductions, and a new political world order. The primary objective of Lean Logistics is to minimize the total system wide costs of the Air Force organization. Currently, the Air Force is seeking to cut costs by reducing inventories, improving repair processes, and employing faster transportation where possible. The purpose of this thesis is to determine if the Air Mobility Express (AMX) current sizing plan is capable of supporting the retrograde assets generated during the sustainment portion of a war. The Dyna-METRIC version 6.4 simulation program is employed to analyze the …

Numerical Analysis Of Two And Three Dimensional Recessed Flame Holders For Scramjet Applications, Douglas L. Davis

Theses and Dissertations

This study investigated the flame holding properties of recessed cavities in supersonic flow using numerical analysis techniques. A simplified analytical model indicated that an important property for flame holding was the lower residence time. Several chemical kinetic rate models for hydrogen and hydrocarbon combustion were compared. The perfectly stirred reactor model also indicated that trace species diffusion should increase flame spreading rate, and that heat loss reduces flame holding limits. After nonreacting calibration, two-dimensional simulations confirmed the perfectly stirred reactor results for blowout limits. Also, the effect of trace species diffusion on flame spreading was shown to be negligible, and …

An Evaluation Of U.S. Air Force Aviation Fuel Consumption Factors To Accurately Predict Aviation Fuel Costs By Aircraft Mission, Design, And Series, Jodi A. Clayton

Theses and Dissertations

The purpose of this thesis was to undertake a systematic, scientific study of the accuracy of Air Force published fuel factors to estimate fuel costs at MAJCOM level by mission, design, and series (MDS) since the implementation of the Fuels Automated Management System (FAMS) under the current environment of decentralized aviation fuel (AVFUEL) funding. The research found that, at MAJCOM level, the use of USAF published AVFUEL factors in estimating out-year costs would have overstated costs in both fiscal year (FY) 1994 and FY 1995 by $2.5 M (FY 1994), by $.25 M (FY 1995), and may potentially understate costs …

An Analysis Of The Relationship Between Risk Alignment And Cost Performance, Christopher M. Wegner

Theses and Dissertations

This thesis investigates the relationship between risk alignment and cost performance in DoD procurement. Both the government and the contractor conduct independent assessments of the perceived risk in a contract. The results of inaccurate risk assessments are undesirable consequences, one of which is the inability to achieve cost targets. If both the contractor's and the government's perceptions of risk are in alignment with the actual risk involved in a contract, then we would expect minimal impact. If, however, either or both parties fail to accurately assess the actual risk, then we would expect consequences, such as cost overrun/underrun. The level …

Integration Of The Distribution And Repair In Variable Environments (Drive) Model Into Micap Policy, Bradley E. Anderson

Theses and Dissertations

The United States Air Force has implemented the Distribution and Repair In Variable Environments (DRIVE) Model to a limited degree for a limited range of items, and policy makers seem unsure as to the proper level of DRIVE utilization. New asset release sequences and policies have been proposed without evidence to support those decisions. The purpose of this study is to explore different levels of DRIVE implementation relating to proposed asset release policies in order to provide some evidence on which policy could best support Air Force weapon systems. A second purpose of this study is to show how the …