Engineering Commons^™

Relative And Absolute Timing Jitter In Actively Mode-Locked Semiconductor Lasers, Dennis J. Derickson, A. Mar, J. E. Bowers

Electrical Engineering

No abstract provided.

Acuta Enews September 1990, Vol. 19, No. 9

ACUTA Newsletters

In This Issue

Are colleges aggregators?

President's column

Four workshops scheduled

Revising the directory

A six-node network

Update on Portland

Optical Processors For Smart Structures, Barry G. Grossman, Howard Hou, Ramzi H. Nassar

Electrical Engineering and Computer Science Faculty Publications

For underwater fiber-optic sensor arrays containing hundreds of sensors as well as smart aerospace structures and skins using fiber-optic strain sensor arrays, the output of the sensors are optical signals that are a function of the measurand. We are also employing optical signals to energize smart-structure actuators (shape-memory alloys). An all-optical processor would thus seem to be logical choice for the processor since we must simultaneously process, in real time, multiple optical input (sensor) signals and generate multiple output (actuator) signals. In addition, with an all-optical processor, there would be no reduction in processor performance due to converting between optical …

On The Maximum Range Of Flying Wings, Peter J. Torvik

AFIT Documents

The classical equations for determining the maximum range of aircraft with propeller and jet propulsion systems are reviewed, along with previous work conducted to determine the optimal division of aircraft volume between fuselage and wing components. That the jet powered flying wing configuration produces optimal range only for limited geometries is confirmed. The optimal range of aircraft employing high bypass jet engines is explored, and found to lead to a broader range of design parameters for which the flying wing design produces maximum range than is the case when a pure jet system is used.

Analysis Of Traffic Accident Data In Kentucky (1985-1989), Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

This report includes an analysis of traffic accident data in Kentucky for the years of 1985 through 1989. A primary objective of this study was to determine average accident statistics for Kentucky highways. Average and critical number and rates of accidents were calculated for various types of highways in rural and urban areas. These data can be used in Kentucky's procedure to identify locations that have abnormal rates or numbers of accidents.

Another objective of this study was to provide data which can be used in the preparation of the problem identification portion of Kentucky's Annual Highway Safety Plan. County …

Road Rater Correlation, R. Clark Graves, David L. Allen

Kentucky Transportation Center Research Report

In this study, a correlation has been conducted between the Model 400B and the Model 2000 Road Rater. Also contained in this study, is a study of the linearity of the Road Rater measurements. Information gained from this study will provide better understanding of Road Rater measurements.

1990 Safety Belt Usage Survey And Evaluation Of Effectiveness In Kentucky, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of the survey was to establish 1990 safety belt and child safety seat usage rates in Kentucky. Data were collected at 100 sites and combined based on vehicle miles travelled for a given type of highway, rural or urban location, and county population category. Also included in this report is an analysis of accident records evaluating the effectiveness of safety belts.

Statewide usage rates were 32 percent for drivers and front-seat passengers (over 19 years of age) and 57 percent for children under four years of age (front and rear seats). Usage rates had increased significantly in 1990 …

Comment On "On The Fractal Dimension Of Stream Networks" By Paolo La Barbera And Renzo Rosso, David G. Tarboton, Rafael L. Bras, Ignacio Rodriguez-Iturbe

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Pesticide Use On Utah's Crops, Howard M. Deer, Richard C. Peralta, Majid Ehteshami

Civil and Environmental Engineering Faculty Publications

Utah State University's Cooperative Extension Service has placed high priority on a Water Quality Initiative for Utah. As a part of that emphasis, a research project was initiated to analyze the hazards that agricultural chemicals pose to Utah's ground water. The initial phase of this research was to determine those locations in Utah that are at greatest risk of ground water contamination by pesticides. This was accomplished by interfacing data on pesticide usage with soil and hydrologic factors. The results identified specific areas in the state where potential hazards exist. This report summarizes data on the use of pesticides on …

Experimental Performance Of A Binary Phase-Only Optical Correlator Using Visual And Infrared Imagery, Samuel Peter Kozaitis, Sandra L. Halby, Wesley E. Foor

Electrical Engineering and Computer Science Faculty Publications

Experimental results of an optical binary phase-only correlator using both visual and IR imagery are presented. The inputs to the correlator originate from actual aerial imagery containing aircraft and a variety of distortions. Filters used as a database for the system are derived from models of aircraft. Digital image processing techniques are used on images before being input into the optical correlator to enhance the performance of the system. Both noise removing and segmentation techniques are investigated. Input images to the correlator are displayed on a 128×128 magneto-optic spatial light modulator (SLM). Experimental results are presented which show that the …

Studies In The Hybrid Deterministic Parsing, Stan C. Kwasny, Anne M. Johnstone, Barry L. Kalman

All Computer Science and Engineering Research

This report details research plans to extend work on hybrid deterministic parsing. The approach is hybrid in its combination of symbolic and sub-symbolic (connectionist) approaches. The research is investigating (1) new and more robust architectures for deterministic parsing which are hybrid mixtures of symbolic and sub-symbolic components, (2) combinations of syntax with lexical access and other components of natural language processing in order to determine how the distributed patterns of connectionism may enable better interfaces among these components, and (3) properties of the rules in the rule-based deterministic processing of natural language that make them most suitable for sub-symbolic training. …

Optimized Cross Correlation Waveforms For First Order Correlation Loops, Kurt Louis Kosbar

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, the steady state mean square tracking error of first order correlation loops is minimized by varying the locally generated cross correlation function produced by the voltage controlled oscillator. This analysis should assist in the design of modified first order delay locked loops used for pseudonoise code synchronization in direct sequence spread spectrum receivers. The optimum cross correlation waveform is generated by filtering a replica of the originally transmitted signal. The optimal filter imposes a 90 degree phase shift at all frequencies and has an amplitude response that is a function of the channel signal to noise ratio. …

Real-Time, In-Situ Measurement Of Film Thickness And Uniformity During Plasma Ashing Of Photoresist, Richard N. Savage, Horace Simmons, John T. Davies, Thomas Metz

Materials Engineering

This paper will discuss the performance of equipment which monitors and so controls photoresist thickness and uniformity during plasma ashing without interfering with the process. Practical monitoring of a subtractive process of this type is significantly more complex than monitoring deposition processes. An initial absolute thickness measurement is needed. In addition the device must view the layer through a luminous medium and cannot rely on simple optical interference fringe counting. The equipment is self-calibrating and sensitive to layers dnm thick. An application to partial plasma resist ashing in high uniformity equipment will be described. Application to other films (e. g. …

Puffing Biological Material, Frederick A. Payne

Biosystems and Agricultural Engineering Faculty Patents

A method and apparatus for puffing biological material such as fruits and vegetables are provided. The method includes the steps of: (a) placing the material in a pressure chamber; (b) subjecting the material to a puffing gas such as carbon dioxide at an increased pressure between substantially 400 and 1200 psi; (c) quickly releasing the puffing gas pressure in less than 1 second to puff the material; and (d) drying the material after puffing to set it in the puffed state. The material is prepared for puffing by sizing so as to include at least one dimension of between substantially …

Nondestructive Detection Of An Undeserable Metallic Phase, T1, During Processing Of Alumnum-L Thumalloys, Otto Buck, David J. Bracci, David C. Jiles, Lisa J.H. Brasche, Jeffrey E. Shield, Leonard S. Chumbley

Department of Mechanical and Materials Engineering: Faculty Publications

A method is disclosed for detecting the T1 phase in aluminum-lithium alloys through simultaneous measurement of conductivity and hardness. In employing eddy current to measure conductivity, when the eddy current decreases with aging of the alloy, while the hardness of the material continues to increase, the presence of the T1 phase may be detected.

Method For Fabricating Or Modifying An Article Comprising The Removal Of A Polymer Coating, Bonnie Bachman, Elizabeth A. Hofstatter, Joan M. Ritter, Jerry J. Rubin

Economics Faculty Research & Creative Works

Disclosed is a method for removing poly-para-xylylene, its derivatives, and copolymers (collectively called "parylene") from bodies, including relatively large bodies such as printed circuit (PC) boards, that is capable of yielding relatively high removal rates. A body such as a PC board coated with parylene is placed into a reaction chamber downstream from a microwave plasma such that plasma discharge products generated by the microwave plasma react with the parylene, etching the parylene without exposing the body to bombardment by energetic ions and/or electrons. The plasma is generated from a gas mixture containing oxygen, a second gas, and optional additives …

Recent Applications Of Glass Science, Norbert J. Kreidl

Materials Science and Engineering Faculty Research & Creative Works

Recent, often exciting, applications of glass science include solid state batteries, electronic switches and memories, electrophotography, solar cells, microspheres for optical strengthening and medical uses, novel glass ceramics such as machinable and bioactive materials, solder glasses, composites, sol-gel glasses, gradient index optics, communication fibers, sensors, non-linear and active optics, and, perhaps, digital optics. The large field of special coatings is not covered in this review. © 1990.

Acuta Enews August 1990, Vol. 19, No. 8

ACUTA Newsletters

In This Issue

New President's column

Conference gets high marks

Regions consolidated

Birds of a Feather

Party Line

Summer-time Blues

Ccfss News August 1990, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.

Load And Resistance Factor Design Of Cold-Formed Steel Reliability Based Criteria For Cold-Formed Steel Members, Ling-En Hsiao, Wei-Wen Yu, Theodore V. Galambos

CCFSS Library (1939 - present)

In the design of steel buildings, the "Allowable Stress Design (ASD)" method has long been used for cold-formed steel structural members in the United States and other countries. In this approach, member forces, or moments, determined on the basis of working loads should not exceed the allowable values. The allowable value is used to prevent the possible structural failure by using an appropriate factor of safety selected primarily on the basis of engineering judgment and long-time experience. Recently, in the United States, the concepts of risk and reliability analysis have been successfully applied to the Load and Resistance Factor Design …

Electrical Use, Efficiency, And Peak Demand Of Electric Resistance, Heat Pump, Desuperheater, And Solar Hot Water Systems, Florida Solar Energy Center, Timothy Merrigan

FSEC Energy Research Center®

Eighty single family residences in Florida were monitored for two years in order to collect data on water heating electrical energy consumption, efficiency, and time-of-day demand. The homes were divided into equally sized samples of four different water heating systems: conventional electric resistance, heat pump, desuperheater and solar hot water systems. Electrical consumption for electric resistance water heaters averaged 8.3 kWh per day in Florida with an average water heating system efficiency of 82%. Desuperheaters used an annual average of 7.4 kWh per day at an annual system efficiency of 110% and heat pump water heaters used 6.1 kWh per …

Monte Carlo Simulation Of Atmospheric Neutron Transport At High Altitudes Using Mcnp, Donald R. Culp, David L. Monti, James R. Shoemaker, David Wesley, Kirk A. Mathews

AFIT Documents

Neutron transport calculations were performed using the Monte Carol code, MCNP. The transport problem considered has a point source at high altitude (40 km). Since atmospheric density decreases with altitude, two-dimensional effects (cylindrical coordinates) can be important. Results were compared to those obtained with the SMAUG-II computer code, which performs mass-integral scaling of approximate fits to one-dimensional spherical discrete ordinates solutions. These comparisons show the importance of two-dimensional computations. The report discusses practical issues of applying MCNP to this problem, without code modifications and includes example input files for MCNP and for SMAUG-II. Computational modelling of neutron transport in the …

Extension Of A Noninteractive Reliability Model For Ceramic Matrix Composites, Stephen F. Duffy, Robert C. Wetherhold, Lalit K. Jain

Civil and Environmental Engineering Faculty Publications

In the next decade ceramic composites will increasingly be used as high-temperature components in advanced gas turbines. Ceramic components will allow an increase in the operating temperature of the gas stream (measured by the turbine entry temperature), thereby resulting in greater fuel economy in aerospace and automotive turbine applications. Since these materials will be produced from abundant nonstrategic materials, computational structural mechanics methods are evolving to keep pace with this technology. As a result, establishing protocols for sound design methodology, which is the subject of this technical note, is the focus of much current analytical research.

Our objective was to …

Correlation Of Astm And Kentucky Cbr Methods For Fayette County, Tony L. Beckham, David L. Allen

Kentucky Transportation Center Research Report

No abstract provided.

Guide To Revenue Calculations—Local Option Highway User Tax 1990, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

This guide is provided to explain the output generated by the computer programs, and to suggest ways in which the results can be adapted to specific LOHUT proposals before a County Council. HERPICC neither endorses nor opposes passage of a LOHUT. The revenue projections it provides are intended to be an aid to well-informed decision-making on the part of a county’s citizens and its County Council.

Optical Switch, Richard N. Savage

Materials Engineering

An optical switch for transmitting light between a first location and a selected one of a plurality of second locations. The switch includes a mirror having a concave, reflective surface and an axis. The switch also includes a plurality of fiber optic cables, one of which is disposed at the first location and the remainder of which are disposed at the second locations, each cable having a light transmission face at their respective locations. The light transmission face at the first location is substantially parallel to the focal plane of the mirror. The light transmission face at each of the …

Control Of Vortical Separation On A Circular Cone, Nikos J. Mourtos

Faculty Publications

For conical bodies, at moderate angles of attack, the flow separates from the lee side, forming two vortices. Although the vortex lift contrihution is highly desirable, as the angle of attack increases, the vortex system becomes asymmetric, and eventually the vortices breakdown. Thus, some control of the separation process is necessary if the vortex lift is to be exploited at higher angles of attack. The theoretical model which is used in this analysis has three parts. First, the 'single line-vortex' model is used within the framework of 'slender-body theory' to compute the outer inviscid field for specified separation lines. Second, …

Pavement Deflection Test Database, Bobby W. Meade, David L. Allen

Kentucky Transportation Center Research Report

Pavement deflection measurements have been collected on various pavement types by both research and the Pavement Management Branch of the Transportation Cabinet for several years. This report outlines the establishment of a data base of deflection measurements which have been collected. A index program has been developed to search the available data base for pavement sections which meet given criteria. This data base will provide up-to-date information which may be used for both research and pavement management activities. The presence of historical data will assist in evaluating the structural performance of various pavement types. It will also provide additional information …

Acuta Enews July 1990, Vol. 19, No. 5

ACUTA Newsletters

In This Issue

Long distance aggregators: A new wrinkle

Telecommunications: one of 'hottest' careers

Message From President

Portland Seminar to give full story on TMS

Do thorough check before joining aggregator

Portland Seminar to give full story on TMIS

Party Line

Touch screens may replace Touch Tone

Workstations pay for themselves in 9 months

Univ. of Chicago fits old halls with new wires

Funding sought for high speed 'data highway'

Proposed Revisions To Kentucky Revised Statutes, Theodore Hopwood Ii, Donald G. Hartman

Kentucky Transportation Center Research Report

No abstract provided.