Engineering Commons^™

Comparison Of Timing Jitter In External And Monolithic Cavity Mode-Locked Semiconductor Lasers, Dennis J. Derickson, P. A. Morton, J. E. Bowers, R. L. Thornton

Electrical Engineering

A comprehensive timing jitter comparison is made for mode-locked semiconductor lasers using active, passive, and hybrid mode-locking techniques in both external and monolithic cavity configurations. Active mode locking gives the lowest residual rms timing jitter of 65 fs (150 Hz-50 MHz), followed by the hybrid and passive mode-locking techniques. It is found that monolithic cavity devices with all active waveguides have higher timing jitter levels than the comparable external cavity case.

Polymer Research In Austria. I: Introduction And The Facilities, Otto Vogl, Josef Schurz, Bernd Thrattnigg, Klaus Hummel, Wolfgang Daimler, Klaus Lederer

Emeritus Faculty Author Gallery

No abstract provided.

Japan-U.S. Seminar On Polymer Synthesis, Otto Vogl, Hiroyuki Nishide

Emeritus Faculty Author Gallery

No abstract provided.

Evaluation Of Torsional Provisions In Seismic Codes, Anil K. Chopra, Rakesh K. Goel

Civil and Environmental Engineering

The effects of plan asymmetry on the earthquake response of code-designed, one-story systems are identified with the objective of evaluating how well these effects are represented by torsional provisions in building codes. The earthquake-induced deformations and ductility demands on resisting elements of asymmetric-plan systems, designed according to several different codes, are compared with their values if the system plan were symmetric. The presented results demonstrate that the design eccentricity in building codes should be modified in order to achieve the desirable goal of similar ductility demands on asymmetric-plan and symmetric-plan systems. The design eccentricity should be defined differently for elastic …

Unsteady Flow In Vertical, Converging Tubes, Hamid Johari, William W. Durgin

Office of the Provost Scholarship

The discharge of liquids from vertical tubes with various contraction geometries was studied via the unsteady Bernoulli equation. The temporal variations of the exit velocity and fluid level in the tube were found from the numerical integration of nonlinear differential equations. Sudden, quadratic, and exponential contraction geometries were considered. For inlet to exit area ratios greater than two, the flow initially accelerates to a maximum speed and then it decelerates for the geometries studied. The exponential contraction has the shortest discharge time. The solutions also reveal that the largest possible velocity and the shortest discharge time are achieved in a …

Material Handling In A Flexible Manufacturing Systems Processing Part Families, Paul Savory, Gerald Mackulak, Jeff Cochran

Department of Industrial and Management Systems Engineering: Faculty Publications

The objective of this simulation study is to analyze the system performance of a six machine flexible manufacturing system cell in which a material handling system is to be incorporated. The analysis focuses on determining the production potential of the cell by grouping common parts into "families". To accomplish this, computer simulation models are developed using the SIMAN simulation language.

Initially the manufacturing cell is modeled with no material handling system to get an upper bound estimate of production output. We next explore the impact that an automatic guided vehicle (AGV) has on system performance of the manufacturing system cell. …

9th Conference On Senior Engineering Design Projects, College Of Engineering And Applied Sciences

Senior Engineering Design Conference

The 9th Conference on Senior Engineering Design Projects was held on December 10, 1991 at the College of Engineering and applied Sciences on the Parkview Campus of Western Michigan University. The college sponsors the conference to showcase the work of its graduating seniors, who are required to complete a capstone project that puts into practice what they have learned. Many of the projects are sponsored by business and industry.

Acuta Enews December 1991, Vol. 20, No. 12

ACUTA Newsletters

In This Issue

10-XXX gives occasion for fraud

President's Message

YaleNET, a variety of services

Think ahead to prevent fraud

MOREnet links 12 campuses

Positions available

Illustrative Examples Based On The Asce Standard Specification For The Design Of Cold-Formed Stainless Steel Structural Members, Shin-Hua Lin, Wei-Wen Yu, Theodore V. Galambos

CCFSS Library (1939 - present)

PREFACE During the past four years, two methods were developed for the design of stainless steel structural members at the University of Missouri-Rolla with consultation of Professor T. V. Galambos at the University of Minnesota. One of the methods is based on the load and resistance factor design (LRFD) and the other is based on the allowable stress design (ASD). Both design methods are now included in the new ASCE Standard 8-90, Specification for the Design of Cold-Formed Stainless Steel Structural Members. At the September 21, 1990 meeting of the Control Group of the ASCE Stainless Steel Cold-Formed Section Standards …

Part 1 Of The Mcmaster University Laboratory Test Program On Brick Veneer/Steel Stud Wall Systems, Robert G. Drysdale, Normand Breton

CCFSS Library (1939 - present)

The behaviour of steel stud backup wall panels subjected to lateral loads was investigated experimentally and analytically. In addition, various steel stud to track connections were investigated experimentally.

The experimental work consisted of the fabrication and testing of 109 steel stud to track connections. Thirty-two full size steel stud backup wall panels were also tested. Some of the panels were braced with various types of commonly used steel bridging while others were braced with gypsum board sheathing or Styrofoam SM insulation. Twelve beam tests were also performed in order to establish the flexural bending capacity of the steel studs tested. …

Seat Belt Attitudinal Survey, Kenneth R. Agent

Kentucky Transportation Center Research Report

The primary objective of this study was to conduct a statewide survey to determine public opinion of a statewide mandatory safety belt law. The survey was conducted so that opinions could be analyzed by areas of the state. The method used to separate the state into geographic regions was to use the boundaries of the 15 Area Development Districts (ADD). A mail survey was conducted with 1,000 questionnaires sent to each ADD. A response rate of 51 percent was obtained.

The respondents were in favor of a statewide law requiring use of safety belts. The statewide percentage in favor of …

Neural Control Of Smart Electromagnetic Structures, Michael Thursby, Kisuck Yoo, Barry G. Grossman

Electrical Engineering and Computer Science Faculty Publications

Artificial neural networks (ANNs) and their ability to model and control dynamical systems for smart structures, including sensors, actuators, and plants, are directly applicable to the smart electromagnetic structures (SEMS) concept. The application of neural networks to the area of controls is being reported frequently. The ability of a structure to adapt to impinging electromagnetic (EM) energy will allow the structure to change its reflection characteristics and thus to change its radar signature. By embedding a control element in the structure of a single microstrip patch element, its electrical characteristics can be changed. If such an element can be controlled …

Composite Damage Assessment Employing An Optical Neural Network Processor And An Embedded Fiberoptic Sensor Array, Barry G. Grossman, Xing Gao, Michael H. Thursby

Electrical Engineering and Computer Science Faculty Publications

This paper discusses a novel approach for composite damage assessment with potential for DoD, NASA, and commercial applications. We have analyzed and modeled a two dimensional composite damage assessment system for real-time monitoring and determination of damage location in a composite structure. The system combines two techniques: a fiberoptic strain sensor array and an optical neural network processor. A two dimensional fiberoptic sensor array embedded in the composite structure during the manufacturing process can be used to detect changes in the mechanical strain distribution caused by subsequent damage to the structure. The optical processor, a pre-trained Kohonen neural network, has …

Construction Evaluation Of Hydraway Edge Drains And Outlet Pipes On Interstate 64, L. John Fleckenstein, David L. Allen

Kentucky Transportation Center Research Report

This report documents the installation of the Hydraway edge drain (version two) on 1-64 in Franklin·Woodford-Scott and Fayette Counties. The edge drain was placed on the back side of the trench against the shoulder and backfilled with a sand/slurry.

From observations on this project and several previous projects, the sand/slurry backfill helps to insure the integrity of the drainage system during initial backfilling. It is apparent that the sand slurry backfill provides a better installation in comparison to previous methods using excavated trench material. Notable trench settlement did occur on this project. It is apparent that insufficient water was used …

Resource Integration Using A Large Knowledge Base In Carnot, Christine Collet, Michael N. Huhns, Wei-Min Shen

Faculty Publications

A method for integrating separately developed information resources that overcomes incompatibilities in syntax and semantics and permits the resources to be accessed and modified coherently is described. The method provides logical connectivity among the information resources via a semantic service layer that automates the maintenance of data integrity and provides an approximation of global data integration across systems. This layer is a fundamental part of the Carnot architecture, which provides tools for interoperability across global enterprises.

Test 1656: Ford 5640 (16x4) Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Electrical Characterization Of Metal‐Insulator‐Semiconductor Diodes Fabricated From Laser‐Ablated Yba2Cu3O7−Δ/Yttria‐Stabilized Zirconia Films On Si Substrates, Eric M. Ajimine, Felino E. Pagaduan, M. Mahmudur Rahman, Cary Y. Yang

Electrical and Computer Engineering

The purpose of this investigation is to study the electrical properties of the YBCO/YSZ/Si metal‐insulator‐semiconductor structure and the yttria‐stabilized zirconia (YSZ)/Si interface. The YBCO and YSZ layers were epitaxially grown in situ on Si by pulsed laser deposition. Current‐voltage measurements of devices fabricated on p‐type Si(100) showed a small leakage current density at 292 K, which decreased further at 80 K. Comparison of capacitance‐voltage measurements at 292 K for frequencies between 10 and 400 kHz showed a large variation of capacitance in the accumulation region demonstrating the presence of mobile ions in the YSZ layer. This variation is less pronounced …

Room Temperature Wear Characteristics Of Al2O3-Particle-Reinforced Aluminum Alloy Composite, A. R. Nesarikar, Surendra N. Tewari, E. E. Graham

Chemical & Biomedical Engineering Faculty Publications

Room temperature dry wear and friction properties of a metal matrix composite sliding against cast iron have been studied in a pin-on-plate reciprocating wear tester. The composite consists of Al₂O₃ particles in an aluminum alloy matrix. Wear is caused by abrasion, interfacial adhesion and ploughing of the softer surface with the asperities of the harder surface and the debris. With increasing load the friction coefficient and wear initially increase and then ecrease. The decreases in wear and friction are caused by increased hardness resulting from re-embedding of the fractured Al₂O₃ particles near the surface …

Solder/Polymer Composite Paste And Method, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An improved solder/polymer fluxless composite paste interconnection material having a low reflow temperature to form electrical contacts having good bonding strength and low contact resistance. The present pastes comprise a major proportion of a meltable metal alloy powder filler, free of noble metals and preferably free of lead, a minor proportion of a solution of a temperature-stable thermoplastic polymer having a softening temperature above the melting temperature of the metal powder filler in a volatile solvent which evaporates during reflow, and a minor proportion of a fluxing agent having a boiling point lower than the reflow temperature of the composition …

One-Tier Plastic-Covered Tobacco Curing Structure—Tier Rail Design, George A. Duncan

Agricultural Engineering Extension Publications

A tobacco grower occasionally has insufficient barn space to house his crop. This problem is especially severe when a barn is damaged or destroyed and cannot be repaired or replaced before harvest. Also, those leasing or having extra poundage may need short-term, low-cost housing.

Kentucky weather conditions are suited for curing in conventional barns as well as in other special structures with adequate covering and crop protection.

Improved Efficiency In Semiconducting Polymer Light-Emitting Diodes, David Braun, A. J. Heeger, H. Kromer

Electrical Engineering

We report visible light emission from metal-polymer diodes made from semiconducting polymers, with indium-tin oxide as the “ohmic” contact, and a variety of metals as the barrier metal. Our results, which confirm the discovery by the Cambridge group [Nature347, 539 (1990)], demonstrate that light-emitting diodes can be fabricated by casting the polymer film on indium-tin oxide from solution with no subsequent polymer processing or heat treatment required. Electrical characterization reveals diode behavior with rectification ratios greater than 105 at sufficiently high voltages. Use of an electrode material with low work function leads to more than an order of magnitude improvement …

Acuta Enews November 1991, Vol. 20, No. 11

ACUTA Newsletters

In This Issue

President's message

Distance learning in Maine

FCC backs phone-line video

Pooling purchasing power

Area code shortage

Positions available

A Note On Repeated-Root Cyclic Codes, Robert H. Morelos-Zaragoza

Faculty Publications

In papers by Castagnoli et al. and Van Lint, cyclic codes with repeated roots are analyzed. Both papers fail to acknowledge a previous work by Chen, dating back to 1969, which includes an analysis of even, length binary cyclic codes. Results from Chen’s study are presented.

Population Trends For Indiana Counties, Cities, And Towns 1970–1990, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

This report presents tabulation and rankings that permit a direct comparison of population growth and population totals for city, town, and county units to assist officials in making amore comprehensive interpretation of the 1990 census figures.

Uniform System For Accident Reporting, Jorge A. Vanegas

Indiana Local Technical Assistance Program (LTAP) Publications

This report presents the results of Project 91-08 Task 5, Project 1, Part III: Uniform System for Accident Reporting.

Analysis Of Baseband Equivalent Noise In A First-Order Correlation Loop Utilizing Filtered Pseudonoise Signals, Kurt Louis Kosbar, Christopher J. Scholten

Electrical and Computer Engineering Faculty Research & Creative Works

Conventional direct-sequence and frequency-hopping spread spectrum systems utilize delay-lock loops to track the timing epoch of pseudonoise codes. These devices perform admirably at high signal-to-noise ratios (SNR), however, they are suboptimal at moderate and low SNR. A correlation loop that employs appropriately filtered pseudonoise signals for the local cross-correlation waveform may have superior performance under these conditions. The performance of this modified correlation loop will be determined by the cross correlation function of the transmitted waveform and locally generated reference signals, along with the statistics of the baseband equivalent noise process. In this work, we find the statistics of the …

Green's Law Revisited: Tidal Long-Wave Propagation In Channels With Strong Topography, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Green's Law states that tidal long-wave elevation ζ and tidal transport Q vary with width b and depth h according to ζ ≌ b^−1/2h^−1/4 and Q ≌ b^+1/2h^+/4. This solution is of limited utility because it is restricted to inviscid, infinitesimal waves in channels with no mean flow and weak topography (those with topographic scale L ≫ wavelength λ). An analytical perturbation model including finite-amplitude effects, river flow, and tidal flats has been used to show that (1) wave behavior to lowest order is a function of only two nondimensional parameters representing, respectively, …

Field Performance Report On Corrugated Polyethylene Pipe, L. John Fleckenstein, David L. Allen

Kentucky Transportation Center Research Report

This report documents the installation and performance of corrugated smooth lined polyethylene pipe installed during construction of South Forbes Road in Fayette County, KY 54 in Daviess County, US 62 in McCracken County, Nicholasville Road in Fayette County, US 68/KY 80 in Warren County, KY 127 in Franklin County, US 62 in Hardin County, Donaldson Road and KY 236 in Kenton County, KY 17 in Kenton County, and Anderson Road in Kenton County. The majority of the pipe installed was N-12 pipe manufactured by Advanced Drainage Systems, Inc., and is designated as ADS N-12. ADS N-12 is a corrugated high-density …

Sensitivity Study Of 1986 Aashto Guide For Design Of Pavement Structures, Herbert F. Southgate

Kentucky Transportation Center Research Report

A sensitivity study of 14 items added to the 1986 AASHTO Guide for Design of Pavement Structures indicated: (1) variations in percent reliability were most influential on the design EAL for the same pavement structure while (2) variations in standard deviations had minimal effects. (3) Resilient moduli for base and subbase materials are very dependent upon stress state (or bulk stress). (4) A method was developed to quantify the effect of drainage capabilities for various soils and its effect upon reduction in structural coefficients for base and subbase materials. (5) Literature review revealed 13 relationships to define soil stiffness. The …

1991 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library

Scholars and Artists Bibliographies

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti