Engineering Commons^™

Acuta Enews July 1991, Vol. 20, No. 7

ACUTA Newsletters

In This Issue

ACUTA Forum

Unblocking 1-0-XXX

President's farewell

Affordable fiber to the desk

Value of utility bill audits

$60 million math/science network

Tardiness Heuristic For Scheduling Flexible Manufacturing Systems, Ali S. Kiran, Sema E. Alptekin, A. Celal Kaplan

Industrial and Manufacturing Engineering

This paper evaluates the tardiness performance of a sampling-based adaptive heuristic in a dynamic manufacturing environment. A test bed, following a real world manufacturing system, has been developed. The proposed algorithm has been implemented in this simulated environment. After fine tuning the algorithm, it has been tested in various shop conditions. The results of these simulation studies are summarized.

The Calendar - July And August 1991, Nova University

The Calendar

No abstract provided.

Engineering Estimates And Fhwa Accuracy Criterion, David Q. Hunsucker

Kentucky Transportation Center Research Report

The Federal Highway Administration requires the construction cost estimate of the highway engineer to be a projection of the low bid, and be within +/- 10 percent of the low bid for at least 50 percent of the projects awarded. Construction cost estimates developed by the Estimating Staff of the Kentucky Department of Highways have not always met this criterion in years past.

The Estimating Staff of the Kentucky Department of Highways use an actual cost approach to generate construction cost estimates. It was concluded that the Department's estimating staff possess the ability to do very thorough and accurate work. …

Protective Coating Program Final Report, James E. Funk, Theodore Hopwood Ii, Donald G. Hartman, Christopher M. Oberst, Rick D. Saylor, Anantha R. Sethuraman

Kentucky Transportation Center Research Report

This program consists of two primary segments: 1) installing an environmental monitoring station at the Toyota marshalling yard at Georgetown, Kentucky, and 2) conducting laboratory and field tests of paint and wax-coated painted specimens to assess the protection against acid rain damage afforded by a protective transient coating.

Summary Of Results Of 1990 Field And Laboratory Evaluations Of Pavement Marking Materials (Sashto Regional Test Facility), Kentucky Transportation Center

Kentucky Transportation Center Research Report

This report summarizes the results of data collected as part of the 1990 field and laboratory evaluations of pavement marking materials for the SASHTO Regional Test Facility. The purpose of the Regional Test Facility (RTF) is to minimize the amount of field and laboratory research testing of specific types of materials. This is accomplished by combining efforts in an organized manner to reduce the monetary and man-hour requirements of both the states and industry. A RTF for the twelve SASHTO states was approved at the 1988 SASHTO convention. The twelve SASHTO states are Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, …

Center For Computer And Information Sciences Master Of Science In Computer Science Summer Courses 1991, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer And Information Sciences Master Of Science In Computer Information Systems Summer Courses 1991, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Converting Binary Thresholds Networks Into Equivalent Symmetric Networks, Gadi Pinkas

All Computer Science and Engineering Research

We give algorithms to convert any network of binary threshold units (that does not oscillate) into an equivalent network with symmetric weight matrix (like Hopfield networks [Hopfield 82] or Boltzmann machines [Hinton, Sejnowski 88]). The motivation for the transformation is dual: a) to demonstrate the expressive power of symmetric networks; i.e. binary threshold networks (that do not oscillate) are subsumed in the energy minimization paradigm; 2) to use network modules (developed for the spreading activation paradigm for example), within the energy minimization paradigm. Thus optimization [Tank, Hopfield 88] and approximation of hard problems can be combined with efficient modules, that …

An Access Protection Solution For Heavy Load Unfairness In Dqdb, Lakshmana N. Kumar, Andreas D. Bovopoulos

All Computer Science and Engineering Research

This paper discusses the unfairness issue arising in a 802.6 DQDB network at high loads-- when the traffic demand to a bus exceeds the capacity of that bus. As per the 802.6 protocol, at heavy loads, the end nodes along a bus experience longer delays than the other nodes. The origin and remedy of this heavy load unfairness is discussed. An access control scheme is proposed as a solution. The comparison of the proposed scheme with 802.6 protocol is presented. The simulation results and performance characteristics are discussed under several types of loads. With symmetric load conditions under the proposed …

The Spectrum Simulation System: A Formal Approach To Distributed Algorithm Development Tools, Kenneth J. Goldman

All Computer Science and Engineering Research

We present the Spectrum Simulation System, a new research tool for the design and study of distributed algorithms. Based on the formal Input/Output Automation model of Lynch and Tuttle, Spectrum allows one to express distributed algorithms as collections of I/O automata and simulate them directly in terms of the semantics of that model. This permits integration of algorithm specification, design, debugging, analysis, and proof of correctness within a single formal framework that is natural for describing distributed algorithms. Spectrum provides a language for expressing algorithms as I/O automata, a simulator for generating algorithm executions, and a graphics interface for constructing …

Rapid Display Of Radiographic Images, Jerome R. Cox Jr., Stephen M. Moore, Robert A. Whitman, G. James Blaine, R. Gilbert Jost, L. Magnus Karlsson, Thomas L. Monsees, Gregory L. Hansen, Timothy C. David

All Computer Science and Engineering Research

The requirements for the rapid display of radiographic images exceed the capabilities of widely available display, computer and communication technologies. Computed radiography captures data with a resolution of about four megapixels. Large format displays are available that can present over four megapixels. One megapixel displays are practical for use in combination with large format displays and in areas where the viewing task does not require primary diagnosis. This paper describes an electronic radiology system that approximates the highest quality systems, but through the use of several interesting techniques allows the possibility of its widespread installation throughout hospitals. The techniques uses …

Composition, Superposition, And Encapsulation In The Formal Specification Of Distributed Systems, Kenneth J. Goldman

All Computer Science and Engineering Research

Composition, superposition, and encapsulation are important techniques that work well together for designing large distributed software systems. Composition is a symmetric operator that allows system components to communicate with each other across module boundaries. Superposition is an asymmetric relationship that allows one system component to observe the state of another. Encapsulation is the ability to define the reason about the behavior of a module in terms of a well-defined boundary between that module and its environment, while hiding the internal operations of that module. In this paper, the I/O automation model of Lynch and Tuttle is extended to permit superposition …

Engineering Soils Map Of Washington County, Indiana, Wei-Yao Chen

JTRP Technical Reports

No abstract provided.

Transmission Ellipsometry On Transparent Unbacked Or Embedded Thin Films With Application To Soap Films In Air, R. M.A. Azzam

Electrical Engineering Faculty Publications

The ratio ρ_t = T_p/T_s of the complex amplitude transmission coefficients for the p and s polarizations of a transparent unbacked or embedded thin film is examined as a function of the film thickness-to-wavelength ratio d/λ and the angle of incidence Φ for a given film refractive index N. The maximum value of the differential transmission phase shift (or retardance), Δ_t = argρ_t, is determined, for given N and Φ, by a simple geometrical construction that involves the iso-Φ circle locus of ρ_t in the complex plane. The …

Fabrication Of High-Conductivity, Transparent Electrodes With Trenched Metal Bus Lines, Otto J. Gregory, R. J. Zeto, E. Hryckowian, K. A. Burbank

Chemical, Biomolecular, and Materials Engineering Faculty Publications

A novel transparent electrode system has been developed for thin film electroluminescent displays in which the poor conductivity of the indium-tin-oxide (ITO) electrodes has been augmented by high-conductivity buses of thick aluminum or silver. The augmented electrode system consists of patterned ITO electrodes, 200 Fm wide, centered over narrow aluminum or silver lines 40 ~m wide and separated by an intermediate diffusion barrier film of titanium to promote adhesion to the ITO and prevent blackening of the main ITO electrode by interfacial reactions. The sheet resistances of the augmented ITO electrodes (A1-Ti-ITO and Ti-Ag-Ti-ITO) were lowered by two orders of …

Interaction Of Sodium, Sulfur, And Silica During Coal Combustion, Thomas A. Erickson, Douglas K. Ludlow, Steven A. Benson

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Interaction of Sodium, Sulfur, and Silica at Conditions Typical in a Pulverized Coal Furnace Was Investigated by using Both Model Mixtures and a Synthetic Coal. the Model Mixtures Consisted of Selected Inorganic Constituents that Were Well Mixed in Proportions Typically Found in Low-Rank Coal. the Synthetic Coal Consisted of a Furfuryl Alcohol Polymer with Appropriate Amounts of Sodium, Sulfur, and Silica to Duplicate the Characteristics of Low-Rank Coal. the Model Mixtures and Synthetic Coal Were Burned in a Laminar Flow (Drop-Tube) Furnace at 900, 1100, 1300, and 1500 °C and Residence Times of 0.1,0.5,1.5, and 2.4 S. the Resulting …

Optimal Sustained-Yield Groundwater Pumping Strategy For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Optimal sustained-yield pumping strategies were developed for the irrigated and industrialized eastern shore of the Great Salt Lake. The combined optimization and simulation model contains steady-state, finite difference, quasi-three-dimensional, groundwater flow equations embedded as constraints. The model computes the optimal spatial distribution of sustainable annual groundwater pumping rates for alternative scenarios. The addressed aquifer is a multilayer and confined/unconfined (linear/nonlinear) system. The research can help manage water in the study area, where the demand for water of sufficient quality and quantity is increasing due to urbanization.

Tractor Museum Committee Establishment 1991, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

No abstract provided.

Investigation Of Real-Time Optical Scanning Holography, Bradley D. Duncan

Electro-Optics and Photonics Faculty Publications

Real-time holographic recording using an optical heterodyne scanning technique was proposed by Poon in 1985. The first part of this dissertation provides a detailed theoretical treatment of the technique, based on a Gaussian beam analysis. Topics to be addressed include the derivations of the optical transfer function (OTF) and impulse response of the scanning holographic recording system, reconstructed image resolution and magnification, methods of carrier frequency hologram generation and experimental verification of the recording technique based on careful measurements of a hologram corresponding to a simple transmissive slit. Furthermore, computer simulations are presented pertaining to the incoherent nature of the …

The Use Of A High Level Cfd Code In Engineering Education, J.E.S. Venart, P. Lemieux, A.C.M. Sousa, D. Tatchell

Mechanical Engineering

An advanced multipurpose Computational Fluid Dynamics (CFD) code, FloSYS, developed for use in a CAD/CAE environment has been utilized in undergraduate and graduate courses in heat transfer. Problems are introduced at an introductory level in: -steady 2- and 3-dimensional conduction, -transient 1-, 2-, and 3-dimensional conduction, -free convective cavity flow with conjugate heat transfer, and -turbulent flows with heat transfer. More sophisticated problems, related to the use of porous media concepts for modelling heat exchangers, and compartment fire modelling are introduced at a more senior level. After one year's experimental use, the CFD code is being recommended for use in …

Tensile Strength Of Welded Connections, Wei-Wen Yu, Roger A. Laboube

CCFSS Library (1939 - present)

PREFACE The tensile strength of an arc spot weld is given only limited attention in the current edition of the AISI Specification for the Design of Cold-Formed Steel Structural Members. To broaden the design engineer's understanding of the behavior of arc spot welds, and to expand the specification's application for arc spot welds, the American Iron and Steel Institute, in 1989, initiated a research study at the University of Missouri-Rolla. The UMR research consisted of a comprehensive literature review, and experimental study which comprised of over 260 individual connection test specimens. The test specimen selection enabled the investigation of the …

Flexural Behavior Of Web Elements With Openings, Roger A. Laboube, Wei-Wen Yu, K. D. Batson

CCFSS Library (1939 - present)

INTRODUCTION The purpose of this phase of the research has been to investigate the flexural behavior of C-shaped members with web openings. Three common industry standard C-sections were tested as outlined in the first progress report. The web openings were located at 24 inches on center as illustrated in Fig. 1. Each test specimen was subjected to two point loads until the ultimate flexural strength of the member was obtained. This report summarizes the test procedure and results of the research to date.

Energy Use In Attached And Detached Residential Developments: Survey Results, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

The relationship between land use, density, dwelling types and energy use in Florida has never been comprehensively examined. Few people consider both energy used in housing and energy used for local transportation. Florida state officials and some land planners have called for compact urban growth to reduce traffic congestion and travel distances. However, energy is rarely mentioned in these arguments. Local governments are trying to respond to the state's concern for compact growth. Developers, on the other hand, are concerned with meeting the local regulations. Unfortunately, energy use is seldom considered and there is little data available to guide decision …

Investigation Of Air Distribution System Leakage And Its Impacts In Central Florida Homes, Florida Solar Energy Center, James B. Cummings

FSEC Energy Research Center®

Testing for air leakage in air distribution systems was done in 160 central Florida homes. Tracer gas tests found that infiltration rates were three times greater when the air handler was operating that when it was off, indicating that there are large leaks in the air distribution system. Infiltration averaged 0.91 air changes per hour (ach) with the air handler (AH) operating continuously and 0.28 ach with the AH off. Return leaks were measured by tracer gas and found to average 10.7% of AH total flow. House airtightness, in 99 of these homes, determined by blower door testing, averaged 12.7 …

High-Frequency Electrooptic Fabry-Perot Modulators, R. J. Simes, R. H. Yan, C. C. Barron, Dennis J. Derickson, D. G. Lishan, Judy R. Karin, L. A. Coldren, M. Rodwell, S. Elliott, B. Hughes

Electrical Engineering

Electrooptic modulators built from GaAs/Al_xGa_1-xAs Fabry-Perot cavities operating up to 6.5 GHz are reported. The measured frequency response agrees well with the one predicted using an equivalent circuit model derived from high-speed electrical measurements. The parasitic capacitances have been reduced to approximately 30 fF by fabricating the devices on semi-insulating GaAs substrates and integrating them with on-wafer bound pads which have dimensions compatible with microwave coplanar probes.

The Calendar - June 1991, Nova University

The Calendar

No abstract provided.

A Prolog System For Converting Vhdl-Based Models To Generalized Extraction System (Ges) Rules, Michael A. Dukes, Frank M. Brown, Joanne E. Degroat

AFIT Documents

With the advent of VHDL accurate documentation of hardware designs is a practical reality. In the past, schematics were typically used for documentation of hardware designs. However, these schematics would usually become obsolete as the hardware design was being constructed. Deviations in the hardware design would sometimes not be reflected in the schematics. For design groups, failure to update schematics could lead to different parts of a hardware design becoming incompatible. A system to ensure compliance of hardware with its VHDL documentation is presented in this paper. The system, vhdl2ges, is meant to help guide the development of hardware by …

Acuta Enews June 1991, Vol. 20, No. 6

ACUTA Newsletters

In This Issue

Panel to focus on fraud

Interactive video bandwidth

Aggregator requirements

Telex can still be useful

Penn State still pioneering

Positions availabe

Bearing Capacity Analysis Of Pavements, Tommy C. Hopkins

Kentucky Transportation Center Research Report

A multilayered, mathematical model for analyzing the ultimate bearing capacity of soil subgrades and asphalt pavements is presented. Theoretical considerations and mathematical derivations of limit equilibrium equations, based on plasticity principles, for analyzing the ultimate bearing capacity of soil subgrades and partially completed asphalt pavements, and the extension of these equations to the analyses of asphalt pavements composed of multiple layers, are presented. The model is unique since shear strength parameters, Φ and c, (the angle of internal friction and cohesion, respectively) are used to describe each layer of material of the pavement structure and a factor of safety against …