Engineering Commons^™

Evaluation Of Modified Asphalt Mixtures, Kamyar C. Mahboub, Amy Simpson

Kentucky Transportation Center Research Report

The primary objective of this study was to conduct a comparative analysis on various modified asphalt mixture systems in order to determine their suitability for conditions that are commonly encountered in Kentucky.

Several modified asphalt mixture systems were selected for laboratory and field testing (one-mile long field test section on KY 80, Pulaski County). These systems included the following asphalt mixtures: Control, Vestoplast, Polypropylene Fiber, Gilsonite, PMAC #1, Polyester Fiber, and PMAC #2. Laboratory testing included: Marshall stability and flow, mixture air voids and density, indirect tensile strength, moisture damage susceptibility, freeze-thaw damage susceptibility, resilient modulus, and repeated load permanent …

Dna Mapping Algorithms: Abstract Data Types - Concepts And Implementation, Will Gillett, Liz Hanks

All Computer Science and Engineering Research

The conceptual aspects of and the implementation details of a set of self-identifying abstract data types (ADT) are described. Each of the ADTs constitutes a specific class of object, upon which a set of well-defined access functions is available. The intent of these ADTs is to supply a paradigm in which a class of object is available for manipulation, but in which the underlying implementation is hidden from the application programmer. Specific ADTs are the described in some detail. The tagged architecture used to achieve the self-identifying property of the ADTs is presented, and a set of required system-backbone access …

Report Of The 12th F.V. Hunt Postdoctoral Fellow (1989-1990), E. Carr Everbach

Engineering Faculty Works

No abstract provided.

Pump Polarization Effects In Cw Dye Lasers, Lee W. Casperson, W. J. Sandle, A. C. Wilson, D. M. Warrington, R. J. Ballagh

Electrical and Computer Engineering Faculty Publications and Presentations

The effects of pump polarization on the performance of cw dye lasers have been investigated. A recently developed semiclassical model for synchronously pumped mode‐locked dye lasers is adapted to the problem of cw dye‐laser oscillation, and analytic expressions are obtained for the relationship between the pump power, pump polarization, and dye‐laser output power. The theoretical results are compared with experimental data obtained using an argon‐laser‐pumped rhodamine 6G dye laser.

The Difficulty Of Random Attribute Noise, Sally A. Goldman, Robert H. Sloan

All Computer Science and Engineering Research

This paper studies the robustness of pac learning algorithms when the instance space is {0,1}n, and the examples are corrupted by purely random noise affecting only the instances (and not the labels). In the past, conflicting results on this subject have been obtained-- the "best agreement" rule can only tolerate small amounts of noise, yet in some cases large amounts of noise can be tolerated. We show the truth lies somewhere between the two alternatives. For uniform attribute noise, in which each attribute is flipped independently at random with the same probability, we present an algorithm that pac learns monomial …

Computational Learning Theory Lecture Notes For Cs 582 Spring Semester, 1991, Sally A. Goldman

All Computer Science and Engineering Research

This manuscript is a compilation of lecture notes from the graduate level course CS 582, "Computational Learning Theory," I taught at Washington University in the spring of 1991. Students taking the course were assumed to have background in the design and analysis of algorithms as well as good mathematical background. Given that there is no text available on this subject, the course material was drawn from recent research papers. I selected the first twelve topics and the remainder were selected by the students from a list of provided topics. This list of topics is given at the end of these …

Network Model Investigation Of Gas Transport In Bidisperse Porous Adsorbents, John H. Petropoulos, John K. Petrou, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

A capillary network model consisting of a micropore network permeated by one of macropores of randomly varying size has been constructed. Although simplified (to keep computer space and time requirements low) in relation to a real bidisperse porous adsorbent or catalyst, it embodies the salient pore structural features likely to determine the gas-transport behavior of such porous solids. Suitable model calculations of Knudsen gas-phase and surface diffusion enabled us to (i) validate useful approximate methods for the more economical evaluation of network permeability and (ii) demonstrate certain important characteristic effects of nonrandom bidisperse pore structure on transport behavior and their …

Spaceborne Radar Measurement Of Wind Velocity Over The Ocean-An Overview Of The Nscat Scatterometer System, David G. Long, F. M. Naderi, Michael H. Freilich

Faculty Publications

Scatterometry and scatterometer design issues are reviewed. The design of the NASA Scatterometer (NSCAT) to be flown on the Japanese ADEOS mission is presented. Building on Seasat experience, the NSCAT system includes several enhancements, such as three antenna azimuths in each of two swaths, and an onboard digital Doppler processor to allow backscatter measurements to be colocated everywhere within the orbit. These enhancements will greatly increase the quality of the NSCAT wind data. The ground processing of data is discussed, and scatterometers of the next decade are briefly described.

The Fracture Of Ice On Scales Large And Small: Arctic Leads And Wing Cracks, E. M. Schulson, W. D. Hibler

Dartmouth Scholarship

From observations and calculations of crack patterns in ice, it is suggested that a similar mechanism may account for cracking over a wide range of scales.

General Phase Modulation Method For Stored Waveform Inverse Fourier Transform Excitation For Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Shenheng Guan, Patrick R. Jones

Pacific Patents

A method for reducing the dynamic range of FT-ICR signal generated by the SWIFT technique includes the step of time shifting wave packets corresponding to segments of the Fourier spectral magnitude function to prevent coherent summing of the various frequency components of the excitation signal.

Apparatus And Method For Automatically Identifying Chemical Species Within A Plasma Reactor Environment, Richard N. Savage

Materials Engineering

A method and apparatus to control the plasma environment in a semiconductor or thin-film fabrication chamber. The apparatus and method include a means for measuring an optical emission spectrum of the chemical species in the plasma and a library containing a multiplicity of predefined spectral patterns. A processor automatically correlates the spectrum with the predefined spectral patterns in the library, and yields a correlation value for all the correlations. A subset of the predefined spectral patterns based upon the highest correlation values are selected and used to identify the chemical species and abundances thereof in the plasma. A comparator compares …

Visible Light Emission From Semiconducting Polymer Diodes, David Braun, A. J. Heeger

Electrical Engineering

We report visible light emission from Shottky diodes made from semiconducting polymers, confirming the discovery by the Cambridge group [Nature 347, 539 (1990)]. Our results demonstrate that light-emitting diodes can be fabricated by casting the polymer film from solution with no subsequent processing or heat treatment required. Electrical characterization reveals diode behavior with rectification ratios greater than 104. We propose that tunneling of electrons from the recitifying metal contact into the gap states of the positive polaron majority carriers dominates current flow and provides the mechanism for light emission.

Measuring Thermostat And Air Conditioner Performance In Florida Homes, Florida Solar Energy Center, Hugh Henderson, Jr.

FSEC Energy Research Center®

This report summarizes the experimental results from 30 field tests in 23 Central Florida homes during the Summer of 1990. Detailed thermostat measurements were made at each site for a one to three day period. The purpose of this study was to determine how thermostats operate in actual buildings. This knowledge is necessary to understand the part load performance of air conditioners (ACs).

Effects Of Plan Asymmetry In Inelastic Seismic Response Of One-Story Systems, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

The effects of plan asymmetry on the earthquake response of one-story systems are identified by comparing the dynamic response of an asymmetric-plan system and the corresponding symmetric-plan system for a wide range of system parameters—uncoupled lateral vibration period, uncoupled torsional-to-lateral frequency ratio, stiffness eccentricity, and yield factor. Elastic as well as inelastic systems are studied. For the latter, two values of the strength eccentricity are considered: equal to the stiffness eccentricity and zero; the latter is representative of code-designed buildings. Based on the response results for a wide range of system parameters, this paper identifies how the structural response is …

Acuta Enews May 1991, Vol. 20, No. 5

ACUTA Newsletters

In This Issue

Golf outing set for St. Louis

Network ties islands together

Reorganization at Chicago

Recycling phone books

Party Line

Call for nominations

Hydraulic Roughness Coefficients As Affected By Random Roughness, John E. Gilley, S. C. Finkner

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Random roughness parameters are used to characterize surface microrelief. In this study, random roughness was determined following six selected tillage operations. Random roughness measurements agreed closely with values reported in the literature.

Surface runoff on upland areas is analyzed using hydraulic roughness coefficients. Darcy-Weisbach and Manning hydraulic roughness coefficients were identified in this investigation on each soil surface where random roughness values were determined. Hydraulic roughness coefficients were obtained from measurements of discharge rat巳and flow velocity.

The experimental data were used to derive regression relationships which related Darcy-Weisbach and Manning hydraulic roughness coefficients to random roughness and Reynolds number. Random …

Calculating Farm Machinery Field Capacities, J. N. Hancock, Larry D. Swetnam, F. J. Benson

Agricultural Engineering Extension Publications

Calculating field capacities is just part of the overall concept of farm machinery management. Successful farm machinery management does not guarantee a profit, but machinery costs are a major expense and they must be monitored and managed. Therefore, the efficient use of farm machinery starts with determining working capacity in conjunction with the amount of work to be accomplished in a timely manner.

The Calendar - May 1991, Nova University

The Calendar

No abstract provided.

Cost Effective Maintenance Contracting -- A Literature Review, Bobby W. Meade, David Q. Hunsucker

Kentucky Transportation Center Research Report

Faced with ever increasing maintenance needs and constrained resources for meeting those needs, government agencies are searching for the most cost effective means of conducting highway maintenance. One alternative being used is contracting highway maintenance to private agencies. This report includes the findings of a literature search of articles pertaining to contract maintenance.

Review of the articles acquired in the literature search indicates that contract maintenance is increasing in usage and is a cost effective alternative.

Evaluation Of Highway Geometrics Related To Large Trucks, Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

One objective of this study was to determine the extent of highway safety and geometric problems associated with larger trucks using Kentucky's highways. The accident analysis involved both a general analysis of all truck accidents statewide as well as the identification of specific high-accident locations. A second objective was to identify criteria which can be used in identifying roadway sections that cannot safely accommodate large trucks.

The accident analysis given can be used to investigate locations which have a high number of truck accidents. The general accident statistics related to trucks can be used in the investigation of the high-accident …

Investigation Of Threaded Code, K. E. Graves, Paul D. Stigall

Computer Science Technical Reports

The design, structure and performance of threaded code are examined through the development of a threaded. code classification system and the modification of the threaded code technique used by a Forth programming language implementation. The classification system distinguishes threaded code designs by three elements: the interpreter, the code structure and the reference method to routines. Threaded code designs from the literature are described using the new classification scheme. The threaded code techniques of variable depth indirect threaded code and token indirect token threaded code are examined in a Forth programming language system on an INMOS IMS T222 transputer. Their design …

Investigation Of Threaded Code, K. E. Graves, Paul D. Stigall

Computer Science Technical Reports

The design, structure and performance of threaded code are examined through the development of a threaded. code classification system and the modification of the threaded code technique used by a Forth programming language implementation. The classification system distinguishes threaded code designs by three elements: the interpreter, the code structure and the reference method to routines. Threaded code designs from the literature are described using the new classification scheme. The threaded code techniques of variable depth indirect threaded code and token indirect token threaded code are examined in a Forth programming language system on an INMOS IMS T222 transputer. Their design …

Field-Equation Approximations And The Dynamics Of High-Gain Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Semiclassical models for laser-dynamics studies typically incorporate a derivative approximation that reduces the second-order wave equation for the electric field to a first-order equation. It is shown here that this approximation and further frequency approximations are not necessary and may lead to significant errors for some high-gain laser systems. A more exact analysis also reveals a partial decoupling of the electric and magnetic fields that occurs with fast transient phenomena. These ideas are illustrated in terms of well-known dynamical effects.

Effects Of Alternative Sprinkler Irrigation Parameters On Pesticide Movement, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill, Antonio Maria Requena, Howard M. Deer, Majid Ehteshami

Civil and Environmental Engineering Faculty Publications

The relative reduction in potential ground-water contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate infiltration depths. The movement of pesticides through soils following sprinkler irrigations was simulated with one-dimensional model. Pesticide contamination of ground water can be reduced by careful selection of pesticides, properly designed irrigation systems and improved water management techniques. Procedures for selecting an appropriate sprinkler design and pesticide are presented.

Applying Formal Verification Methods To Pure Rule-Based Programs, Rose F. Gamble, Gruia-Catalin Roman, William E. Ball, H. Conrad Cunningham

All Computer Science and Engineering Research

Reliability, defined as the guarantee that a program satisfies its specifications, is an important aspect of many applications for which rule-based expert systems are suited. Verification refer to the process used to determine the reliability of the rule-based program. Because past approaches to verification are informal, guarantees of reliability cannot fully be made without severely restricting the system. On the other hand, by constructing formal specifications for a program and showing the program satisfies those specifications, guarantees of reliability can be made. This paper presents an assertional approach to the verification of rule-based programs. The proof logical needed for verification …

Composition And Method For Radiation Synovectomy Of Arthritic Joints, D. E. Day, Gary J. Ehrhardt

Materials Science and Engineering Faculty Research & Creative Works

Radioactive microspheres for radiation synovectomy of arthritic joints in a mammal comprises a biodegradable glass material and a beta radiation emitting radioisotope chemically dissolved in and distributed substantially uniformly throughout the glass material. The biodegradable glass material may be lithium silicate, lithium aluminosilicate, lithium aluminoborate, lithium germa- nate, lithium aluminogermanate, potassium silicate, potassium aluminosilicate, potassium aluminoborate, potassium germanate or potassium aluminogermanate and the beta radiation emitting radioisotope may be samarium-153, holmium-166, erbium-169, dysprosium-165, rhenium-186, rhenium-188 or yttrium-90. Method for preparing such microspheres and for carrying out radiation synovectomy of arthritic joints utilizing such microspheres are also disclosed.

Radioactive Glass Microspheres, D. E. Day, Gary J. Ehrhardt

Materials Science and Engineering Faculty Research & Creative Works

A radioactive microsphere for radiation therapy of a mammal comprising a biologically compatible glass material containing a beta or gamma emitting radioisotope distributed substantially uniformly throughout the glass. Advantageously, the radioisotope is produced by irradiation of the microsphere.

Hybrid Wafer Scale Microcircuit Integration -- [ 5008213 ], Edward S. Kolesar Jr.

AFIT Patents

A wafer scale integration arrangement wherein integrated circuit die of varying size, fabrication processes, and function are commonly mounted in the same host wafer using a filled epoxy material of special characteristics. The mounting epoxy material also serves as a substrate for the die interconnecting conductors in regions adjacent the mounted die. The described assembly also includes a newly available photosensitive polyimide material as a planarization and passivation covering for the die and hose wafer and as a mounting surface for an interconnecting metal conductor array. Multiple levels of interconnection metal. Fabrication processes for the die to host wafer attachment …

The Thermal Response Of Downhill Skis, S. C. Colbeck, G. C. Warren

Dartmouth Scholarship

No abstract provided.

Optical And Magneto-Optical Characterization Of Tbfeco Thin Films In Trilayer Structures, William A. Mcgahan, Ping He, Liang-Yao Chen, Sal Bonafede, John A. Woollam, F. Sequeda, T. Mcdaniel, H. Do

Department of Electrical and Computer Engineering: Faculty Publications

A series of TbFeCo films ranging in thickness from 100 to 800 Å have been deposited in trilayer structures on silicon wafer substrates, with S₃N₄ being employed as the dielectric material. These films have been characterized both optically and magneto-optically by variable angle of incidence spectroscopic ellipsometry, normal angle of incidence) reflectometry, and normal angle of incidence Kerr spectroscopy. From these measurements, the optical constants n and k have been determined for the TbFeCo films, as well as the magneto-optical constants Ql and Q2. Results are presented that demonstrate the lack of dependence of these …