Engineering Commons^™

Correlation Between Particle Velocities And Conditions Of Abrasive Waterjet Formation, Wei-Long Chen

Dissertations

The velocities of water and abrasive particles in abrasive waterjet(AWJ) were measured by the use of Laser Transit Anemometer(LTA). A setup for the velocity measurement was constructed and a statistical technique was used to improve the accuracy of the velocity determination. A comparison of the magnitude of velocities determined by LTA, Piezoelectric Force Transducer and Schlieren Photograph clearly indicates the feasibility of the use of LTA.

The velocities of water and particles were measured for different diameters of water and slurry nozzles, abrasive mass flow rates and particle sizes. The performed experiments enabled us to evaluate the effects of conditions …

Solar Energy In Florida, Florida Solar Energy Center, Carolyn King Burns

FSEC Energy Research Center®

To understand Florida's position in the development of solar technologies it's necessary to visualize a bigger picture. Currently, the United States spends over $38 billion per year for crude oil and petroleum product imports, whereas appropriations for research and development on solar energy technology total less than $120 million per year.

Not only do we operate within a global economy, we also operate within a global environment. If the greenhouse effect and global climate change force nations to drastically reduce carbon dioxide emissions, there are very few alternatives to fossil fuels for power production. In a world of dwindling energy …

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 arithmetic joints in a mammal comprise 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. Methods for preparing such microspheres and for carrying out radiation synovectomy of arthritic joints utilizing such microspheres are also disclosed.

Contours Of Constant Pseudo-Brewster Angle In The Complex Є Plane And An Analytical Method For The Determination Of Optical Constants, R. M.A. Azzam, Ericson E. Ugbo

Electrical Engineering Faculty Publications

The locus of all points in the complex plane of the dielectric function є[є_r + jє_i = |є| exp(jθ)], that represent all possible interfaces characterized by the same pseudo-Brewster angle θ_pB of minimum p reflectance, is derived in the polar form: |є| = l cos(ζ/3), where l = 2(tan²Φ_pB)k, ζ = arccos(- cosθ cos²Φ_pB/k³), and k = (1 - 2/3 sin²Φ_pB)½. Families of iso-Φ_pB contours for (I) 0° ≤ Φ_pB ≤ …

Enhanced Magneto-Optic Kerr Effects In Thin Magnetic/Metallic Layered Structures, William A. Mcgahan, Liang-Yao Chen, Z. S. Shan, David J. Sellmyer, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

Enhanced Kerr rotation spectra are measured in thin magnetic layers on silver. Also, variable angle of incidence spectroscopic ellipsometry is employed to measure the optical dielectric function of both the thin magnetic layer and the underlying thick silver layer. These results are explained quantitatively using the electromagnetic theory for reflection of light from multiple layers of isotropic and gyrotropic materials.

Dynamic Behavior Of Co₂ Lasers, Li Zhang

Dissertations and Theses

Spontaneous pulsations have been observed in the output of a CO₂ laser. The temporal waveforms, transverse mode patterns, and laser lines are simultaneously measured under various operation conditions. The experimental data show that these pulsations have a direct connection with the transverse modes. We interpret the oscillations as being caused by mode beating, and the frequency shift of the oscillation as resulting from mode pulling. The theoretical explanations for these effects are in good agreement with the experimental results.

Endless State-Of-Polarization Control For Coherent Optical Communication Systems Using Nematic Liquid Crystal, Scott H. Rumbaugh

Dissertations and Theses

One of the obstacles to coherent fiber-optic communications is the unpredictable polarization drift which necessitates the use of an active polarization controlling system to match the polarizations of the signal and local oscillator. The polarization match must be maintained during the reset of any of the finite range components to prevent loss of data. We present a novel and practical system which uses three liquid crystal devices for the polarization matching process. Also, the required reset control algorithm and its derivation are described in detail.

Energy Research Projects, Florida Solar Energy Center, David Lahart

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) is a research and education arm of the State University System hosted by the University of Central Florida. The Florida legislature established FSEC in 1974 to conduct research in alternative energy technologies, to ensure the quality of solar energy equipment sold in Florida, and to educate people about renewable energy technology. One method of disseminating research results has been through teacher education programs and the development of instructional materials. FSEC-developed materials are designed to teach science and social studies research methods and for process skills. All units are field-tested and correlated with student performance …

Iupac 32nd International Congress On Macromolecules "Macro 88", Otto Vogl, Naohuki Koide, Tatsuki Kitayama, Koichi Hatada

Emeritus Faculty Author Gallery

No abstract provided.

An Investigation Of The Combined Heat And Mass Transfer Processes In The Drying Of Hygroscopic Porous Media With Two Disparate Length Scales, Thomas Joseph Phillips

Doctoral Dissertations

A mathematical model describing the drying process in a hygroscopic porous medium with two disparate length scales is formulated. The mathematical model is used to identify the important dimensionless parameters appearing in the problem; and, a parametric study is performed to determine the effects of varying these parameters on the drying process. Of particular interest in this study is to apply the model to the drying of large, round hay bales. Therefore a discussion of how the results of the parametric study impact on the efficient use of a hay drier is also presented.

The results from the parametric study …

The Influence Of Environmental Factors On The Temperature Of The Radiosonde Thermistor, James K. Luers

Doctoral Dissertations

A technique was developed to calculate the radiosonde temperature error as a function of altitude under different environmental conditions. The environmental conditions analyzed include the surface (or cloud) temperature, the atmospheric gaseous constinuents, the aerosol and thermodynamic structure of the atmosphere, the solar elevation angle, the solar albedo, the rise rate of the balloon, and the atmospheric density.

The heat balance equations for the thermistor and lead wires were derived and a sensitivity analysis performed to establish the significance of each heating term. The Air Force LOWTRAN 6 code was used to model the solar and infrared irradiation of the …

Ellipsometric Study Of Al2O3/Ag/Si And Sio2/Ag/Quartz Ashed In An Oxygen Plasma, Bhola N. De, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

Using monolayer-sensitive variable angle of incidence spectroscopic ellipsometry, the silver oxide growth on a silver mirror, coated with an Al₂ O₃ or SiO₂ protective layer, was investigated. The oxidation was done in a pure oxygen plasma asher. The resulting silver oxide growth was monitored accurately as a function of exposure time in the plasma asher. It was found that silver was converted to silver oxide under the protective coating, during ashing of a sample. The optical constants of a dense silver oxide thin film, created by oxidizing in the asher, were also measured.

Investigation And Evaluation Of A Computer Program To Minimize Vfr Flight Planning Errors, Peter Joseph Mcalindon

Master's Theses - Daytona Beach

The purpose of this study was to investigate the effect of computer aided flight planning on flight planning errors. Subjects were selected from the introductory flight courses at Embry-Riddle Aeronautical University. After the subjects completed a conventional VFR navigation log, they were asked to plan the return trip of the flight using a computer aided flight plan. It was initially expected that the computer aided flight plans would have fewer flight planning errors than those calculated using conventional methods. The results supported the hypothesis that flight planning errors are greatly reduced when computer aided flight planning techniques are used.

Optimized Engine Out Procedures To Extend The Range Of Jet Transport Airplanes, Miltos Miltiadous

Master's Theses - Daytona Beach

The purpose of this study was to develop optimum engine-out procedures for the Boeing 747 and 767 on extended flights that will increase the range of the aircraft in case of engine failure. Theory suggests that an optimum amount of bank angle that will minimize drag resulting from asymmetric thrust in a multiengine airplane experiencing an engine failure, can be determined. By banking the airplane into the operative engines by that optimum bank angle, the range of the airplane can be improved significantly. Wind tunnel tests of both a Boeing 747 and a 767 model were performed to determine experimentally …

Iupac 32nd International Congress On Macromolecules "Macro 88", Otto Vogl, Naohuki Koide, Tatsuki Kitayama, Koichi Hatada

Otto Vogl

No abstract provided.

Analysis Of Whisker-Toughened Ceramic Components -- A Design Engineer's Viewpoint, Stephen F. Duffy Phd, Pe, Jane M. Manderscheid, Joseph L. Palko

Civil and Environmental Engineering Faculty Publications

The use of ceramics components in gas turbines, cutting tools, and heat exchangers has been limited by the relatively low flaw tolerance of monolithic ceramics. The development of whisker-toughened ceramic composites offers the potential for considerable improvement in fracture toughness as well as strength. However, the variability of strength is still too high for the application of deterministic design approaches. This report reviews several phenomenological reliability theories proposed for this material system, and reports on the development of a public domain computer algorithm. This algorithm, when coupled with a general-purpose finite element program, predicts the fast fracture reliability of a …

Thiokol/Wasatch Installation Evaluation Of The Redesigned Field Joint Protection System (Concepts 1 And 3) Final Test Report, United States, National Aeronautics And Space Administration

Miscellaney

Redesigned field joint protection system installations were performed between 7 and 15 Nov 1989 at the Thiokol Corporation Static Test Bay T-18. The purpose of the installations was to develop procedures for two field joint protection system redesign concepts (Concepts 1 and 3), and to evaluate the processing capability of each concept. The Concept 1 (Double Cork Band Design) configuration consists of two cork bands with K5NA ablation compound applied between them and to the bottom edge of the aft cork band. The Concept 3 (K5NA Design) configuration consists of a single layer of K5NA over the joint/heater/sensor/pin retainer band …

Structural Characteristics Of Sr1-Xlaxti 3+Δ As A Function Of Oxygen Partial Pressure At 1400°C, S. A. Howard, J. K. Yau, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The structural characteristics of Sr_1-x La_x TiO_3+δ (0≤x≤0.4) at 1400°C have been investigated as a function of ambient oxygen partial pressure. A modified Rietveld pattern-fitting structure-refinement program [H. M. Rietveld, J. Appl. Crystallogr. 2, 65 (1969)] was used to determine the nature of the distortions of the fundamental perovskite unit cell, the degree of lattice perfection, and the cation vacancy concentrations. Specimens equilibrated in forming gas displayed a linear relation between x, the lattice parameters, and the degree of lattice perfection while those samples annealed in air and oxygen deviated significantly from linearity. A monoclinic distortion of …

Application Of Risk Analysis In Investment Decision Making For New Products, Chul Paik

Masters Theses

This study presents the development of a quantitative model to deal with the decision to invest or not invest in the development and production of a new product. It is most applicable to new products which present a high probability of economic failure. The model employs only simple mathematics and statistics, so the decision maker can easily understand the model.

The model uses as input data three variables. These include: (1) the risk of product failure, (2) the maximum loss a company can afford in an investment, and (3) the estimated project cost. These three variables combined furnish as output …

Flotation Deinking Of Ultraviolet Radiation Cured Inks, Narayanasamy Seenivasan

Masters Theses

The objectives of this study were to optimize the variables of pH and surfactant concentration for the maximum flotation efficiency of ultraviolet radiation-cured inks and to increase the understanding of the behavior of the ink particles during flotation. Experiments were designed in two phases: water and ink system and water, fiber and ink system. At 7.t pH at room temperature the flotation efficiency increased with surfactant concentration to 8.2 <μ/>M/L and then dropped with increase in surfactant concentration. Statistical analysis showed that maximum flotation efficiency of 94.8% was obtained at pH of 7.56 at 12.18 <μ/>M/L surfactant concentration. Ink particles …

A Methodology For Developing Correct Rule-Based Programs For Parallel Implementation, Rosanne Fulcomer Gamble

All Computer Science and Engineering Research

Production systems, also called rule-based systems, are very useful in automating certain human expert tasks, but the current technology exhibits many problems. We believe that parallelism is difficult to exploit in production system programs for two reasons. First, the original serial programs are designed with a priori knowledge of an explicit global control mechanism which must be simulated for correct execution in parallel. The second reason for the difficulty is that no formal language exists in which to express these programs and no verification techniques are utilized to prove properties which guarantee correct execution in parallel. With these two obstacles …

Noninteractive Macroscopic Reliability Model For Ceramic Matrix Composites With Orthotropic Material Symmetry, Stephen F. Duffy, Jane M. Manderscheid

Civil and Environmental Engineering Faculty Publications

A macroscopic noninteractive reliability model for ceramic matrix composites is presented. The model is multiaxial and applicable to composites that can be characterized as orthotropic. Tensorial invariant theory is used to create an integrity basis with invariants that correspond to physical mechanisms related to fracture. This integrity basis is then used to construct a failure funciton per unit volume (or area) of material. It is assumed that the overall strength of the composite is governed by weakest link theory. This leads to a Weibull type model similar in nature to the principle of independent action (PIA) model for isotropic monolithic …

Evaluation Of Wick Stabilization Of Approach Fill Foundation (Carroll County), Bobby W. Meade, David L. Allen

Kentucky Transportation Center Research Report

The purpose of this study was to document construction procedures and evaluate the effectiveness of wick drains as a foundation stabilization method. This effort was executed by use of field inspections, photologs, and instrumentation to monitor foundation and field response. Instrumentation included a multipoint settlement gage, settlement platforms, and vertical slope inclinometers.

This procedure was judged to be successful in that 90 percent consolidation of the deep foundation occurred within approximately 100 days. Construction procedures were generally satisfactory.

Development Of A Priority Ranking System For Bridge Rehabilitation And Replacement, Theodore Hopwood Ii, Vishwas G. Oka

Kentucky Transportation Center Research Report

The main objective of this study was to review a Bridge Priority Ranking System for Bridge Replacement developed by the Kentucky Transportation Cabinet Division of Maintenance. The system ranked bridges for improvement (rehabilitation or replacement) based on a benefit/cost ratio.

The system was used to rank a large data base consisting of 267 bridges. Analysis of the rankings revealed that the ranking system gave priority to bridges having low improvement costs. Many of those had low traffic volumes and subsequently, they had high costs of improvement per vehicle served.

The equation used to compute bridge deficiency points was revised. Several …

Integrated Truck Monitoring System, Jerry G. Pigman, John A. Deacon

Kentucky Transportation Center Research Report

The primary objectives of the study are as follows: 1) Develop functional specifications for an integrated truck monitoring system for use in Kentucky, 2) Determine the extent to which KYU numbers (unique identification for large trucks operating in Kentucky) are being displayed as required, 3) Examine the impact of the KYU numbering system on motor carrier operations, and 4) Determine the magnitude of the problems related to trucks using bypass routes to avoid inspection stations.

Accomplishments documented in this interim report include the following: 1) Field studies were conducted to determine the frequency of trucks bypassing inspection stations and compliance …

Irish Building Services News

Building Services Engineering

No abstract provided.

Propagation Of Millimeter Wave Signals In Forests Using The Equation Of Radiative Transfer With Strong Forward Scattering Phase Functions, Nack Yang Cho

Dissertations

A forest is a highly scattering medium at millimeter wave frequencies. The propagation of cw millimeter wave signals in forests has been studied previously, both theoretically and experimentally. Published experimental data verified that continuous wave transmission is possible over lengths of the order of a few hundred meters and that a forest acts to strongly scatter energy in the forward direction. The cw studies yielded the determination of the range dependence, beam broadening effects and depolarization effects of millimeter wave signals in a forest. However, pulse broadening effects, which are of importance particularly in the case of digital signal transmission, …

To The U.S. Department Of Transportation: Comments Of The Environmental Defense Fund On The Secretary Of Transportation’S National Transportation Policy, Robert E. Yuhnke

Air Quality Protection in the West (November 27-28)

20 pages.

Motor Vehicle Air Pollution Control: The Remaining Issues, Michael P. Walsh

Air Quality Protection in the West (November 27-28)

26 pages (includes illustrations).

Contains references.

Agenda: Air Quality Protection In The West, University Of Colorado Boulder. Natural Resources Law Center

Air Quality Protection in the West (November 27-28)

Conference organizers, session moderators and/or speakers included University of Colorado School of Law professor Mark S. Squillace.

Visibility, acid rain, air toxics, and urban air pollution are the topics of an upcoming Center conference on air quality in the West. The conference will be held at the School of Law in Boulder on November 27-28, 1989. Presentations will describe the nature and scope of the issues, the existing legal framework and experience with its implementation, and proposed changes in the law. Emphasis will be placed on air quality issues in the West and efforts underway to address these problems. Special …