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Full-Text Articles in Engineering

Lateral Load Behavior Of Pile Group In Sand, Shamsher Prakash Jan 1990

Lateral Load Behavior Of Pile Group In Sand, Shamsher Prakash

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Optimum Assessment Of Irregular Three-Dimensional Seismic Buildings, Kevin Z. Truman, Franklin Y. Cheng Jan 1990

Optimum Assessment Of Irregular Three-Dimensional Seismic Buildings, Kevin Z. Truman, Franklin Y. Cheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A structural optimization algorithm based on an optimality criteria approach is presented for three-dimensional, statically and dynamically loaded steel or reinforced concrete structures. The theoretical work is presented in terms of scaling, sensitivity analyses, optimality criteria, and Lagrange multiplier determination. The structures can be subjected to a combination of static and dynamic displacement and stress, and natural frequency constraints. The dynamic analyses are based upon the ATC-03 provisions for equivalent lateral force and modal analysis procedures, or multicomponent response spectra modal analyses. Using the algorithm presented, a computer program called ODRESB-3D was developed for analysis and design of various building …


Revised Method Of Approximate Structural Analysis, Richard A. Behr, E. J. Grotton, C. A. Dwinal Jan 1990

Revised Method Of Approximate Structural Analysis, Richard A. Behr, E. J. Grotton, C. A. Dwinal

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Failure Strengths Of Laminated Glass, Joseph E. Minor, Patrick L. Reznik Jan 1990

Failure Strengths Of Laminated Glass, Joseph E. Minor, Patrick L. Reznik

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Laminated glass used in architectural glazing comprises two layers of glass connected by a thin interlayer of polyvinyl butyral. Previously reported nondestructive experimental stress analyses offer evidence that laminated glass behaves like monolithic glass of the same nominal thickness except when temperatures are high. This evidence has been augmented to include failure behavior by destructive tests of a large number of laminated-glass specimens. Test results reveal that failure strengths of annealed laminated-glass specimens are equal to failure strengths of annealed monolithic glass specimens of the same nominal thickness at room temperature and decrease to about 75% of monolithic-glass strength at …


Seal Forces In Structural Glazing Systems, C. V.Girija Vallabhan, Gee D. Chou, Joseph E. Minor Jan 1990

Seal Forces In Structural Glazing Systems, C. V.Girija Vallabhan, Gee D. Chou, Joseph E. Minor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Silicone sealants are used as structural connections between the two glass plates in an insulating glass (IG) unit and between the IG unit and the supporting mullion. These connections become an integral part of the entire glazing system, worthy of attention by structural design engineers. Since the behavior of IG units subjected to lateral pressures, such as wind, is highly nonlinear, von Karman plate equations are employed in the mathematical model developed here. Also, since the two thin glass plates are separated by a sealed air space, a complex interaction occurs between the trapped air space and the glass plates. …


Design Considerations For 1-3 Composites Used In Transducers For Medical Ultrasonic Imaging, Wayne Huebner, Kuiming Liang, Clyde G. Oakley Jan 1990

Design Considerations For 1-3 Composites Used In Transducers For Medical Ultrasonic Imaging, Wayne Huebner, Kuiming Liang, Clyde G. Oakley

Materials Science and Engineering Faculty Research & Creative Works

Ceramic polymer piezoelectric composites with 1-3 connectivity have become an important tool in the design and manufacture of thickness-mode transducers for medical diagnostic ultrasonic imaging. The authors compare annular array transducers made from ceramics alone to those made with these composites to demonstrate the advantages of composites. They examine some of the trade-offs involved in optimizing composite designs for this application. The effects of varying Young's modulus and Poisson's ratio of the polymer phase on the coupling coefficient and high-frequency lateral resonances of the composite are presented


The Fractal Dimension As A Measure Of The Roughness Of Rock Discontinuity Profiles, Y. H. Lee, J. R. Carr, David J. Barr, Charles J. Haas Jan 1990

The Fractal Dimension As A Measure Of The Roughness Of Rock Discontinuity Profiles, Y. H. Lee, J. R. Carr, David J. Barr, Charles J. Haas

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

An important factor in the analysis of deformation and failure of rock masses along discontinuities is the roughness of the jointing surfaces. The fractal dimension is proposed as a method of objectively quantifying the roughness profile of such discontinuities. With this method much less engineering judgement and experience are required in determining the surface roughness,sb than is required for other methods such as the widely used joint roughness coefficient (JRC) suggested by the International Society for Rock Mechanics [1] (Int. J. Rock. Mech. Min. Sci. & Geomech. Abstr. 15, 319-368, 1978). The fractal dimension, suggested by Mandelbrot [2] (Fractals-Form, Chance …


Residual Circulation In Shallow Estuaries 1. Highly Stratified, Narrow Estuaries, David A. Jay, J. Dungan Smith Jan 1990

Residual Circulation In Shallow Estuaries 1. Highly Stratified, Narrow Estuaries, David A. Jay, J. Dungan Smith

Civil and Environmental Engineering Faculty Publications and Presentations

Long-wave theory and simple turbulence closures have been used to show that three distinct types of circulation (highly stratified, weakly stratified, and partially mixed) arise in narrow, shallow estuaries from the finite amplitude of the tide and the interaction of stratification with vertical mixing. Each type has a different dominant process causing the vertical exchange of salt and fresh water on the flood, and each gives rise to a characteristic residual circulation. The tidal circulation in highly stratified shallow estuaries, described herein, is the result of a finite amplitude internal motion driven by the barotropic tide; shear instabilities at the …


Solar Energy In Florida, Florida Solar Energy Center, Carolyn King Burns Dec 1989

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 Dec 1989

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 Dec 1989

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[єr + jєi = |є| exp(jθ)], that represent all possible interfaces characterized by the same pseudo-Brewster angle θpB of minimum p reflectance, is derived in the polar form: |є| = l cos(ζ/3), where l = 2(tan2ΦpB)k, ζ = arccos(- cosθ cos2ΦpB/k3), and k = (1 - 2/3 sin2ΦpB)½. Families of iso-ΦpB contours for (I) 0° ≤ ΦpB ≤ …


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 Dec 1989

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.


Energy Research Projects, Florida Solar Energy Center, David Lahart Dec 1989

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 …


Noninteractive Macroscopic Reliability Model For Ceramic Matrix Composites With Orthotropic Material Symmetry, Stephen F. Duffy, Jane M. Manderscheid Dec 1989

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 …


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 Dec 1989

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 …


Analysis Of Whisker-Toughened Ceramic Components -- A Design Engineer's Viewpoint, Stephen F. Duffy Phd, Pe, Jane M. Manderscheid, Joseph L. Palko Dec 1989

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 …


Development Of A Priority Ranking System For Bridge Rehabilitation And Replacement, Theodore Hopwood Ii, Vishwas G. Oka Dec 1989

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 …


Evaluation Of Wick Stabilization Of Approach Fill Foundation (Carroll County), Bobby W. Meade, David L. Allen Dec 1989

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.


Integrated Truck Monitoring System, Jerry G. Pigman, John A. Deacon Dec 1989

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 …


A Methodology For Developing Correct Rule-Based Programs For Parallel Implementation, Rosanne Fulcomer Gamble Dec 1989

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 …


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 Dec 1989

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 Sr1-x Lax TiO3+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 …


Ellipsometric Study Of Al2O3/Ag/Si And Sio2/Ag/Quartz Ashed In An Oxygen Plasma, Bhola N. De, John A. Woollam Dec 1989

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.


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 Nov 1989

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 Nov 1989

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 Nov 1989

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 …


Conformational Changes In An Epitope Localized To The Nh2-Terminal Region Of Protein C, Carolyn L. Orthener, Rapti D. Madurawe, William H. Velander, William N. Drohan, Frances D. Bettey, Dudley K. Strickhand Nov 1989

Conformational Changes In An Epitope Localized To The Nh2-Terminal Region Of Protein C, Carolyn L. Orthener, Rapti D. Madurawe, William H. Velander, William N. Drohan, Frances D. Bettey, Dudley K. Strickhand

Papers in Biotechnology

Murine monoclonal antibodies, developed following immunization with human protein C, were characterized for their ability tboin d antigen in thpe resence of either CaClz or excess EDTA. Three stablec lones were obtained which produced antiboditehsa t bound to protein C only itnh e presence of EDTA. Allt hree antibodies bound to the light choafi np rotein C on immunoblots and also bound to the homologous proteins factor X and prothrombin in solid-phase radioimmunoassays. One antibody, 7D7B10 was purified and studied further. The binding of 7D7B10 to human protein C was characterized bya KOo f 1.4 nM. In competition studies, it …


The Display And Manipulation Of Temporal Information, Steve B. Cousins, Michael G. Kahn Washington University In St. Louis, Mark E. Frisse Washington University In St. Louis Nov 1989

The Display And Manipulation Of Temporal Information, Steve B. Cousins, Michael G. Kahn Washington University In St. Louis, Mark E. Frisse Washington University In St. Louis

All Computer Science and Engineering Research

Because medical data have complex temporal features, special techniques are required for storing, retrieving, and displaying clinical data from electronic databases. One significant problem caused by the temporal nature of medical data has been called the temporal granularity problem. The temporal granularity problem is said to occur when the set of facts relevant to a specific problem changes as the time scale changes. We argue that what is needed to deal with changes in the relevant time scale are temporal granularity heuristics. One heuristic that we have explored is that, for any level of problem abstraction, and for each type …


Acuta Enews November 1989, Vol. 18, No. 11 Nov 1989

Acuta Enews November 1989, Vol. 18, No. 11

ACUTA Newsletters

In This Issue

A Conversation with Kid Malott, ACUTA Post President

Message From The President

Toronto Seminar a Smash!

Update: More on McGill..

Changing your prefix? Read this first...

Administrative Director's Column


Scattering By A Narrow Gap In An Impedance Plane, John R. Natzke Nov 1989

Scattering By A Narrow Gap In An Impedance Plane, John R. Natzke

Faculty Publications - Department of Electrical Engineering and Computer Science

No abstract provided.


Water Seepage From Unlined Ditches And Reservoirs, Nigel W.T. Quinn, Richard B. Smith, Charles M. Burt, Tracy S. Slavin, Stuart W. Styles, Amir Mansoubi Nov 1989

Water Seepage From Unlined Ditches And Reservoirs, Nigel W.T. Quinn, Richard B. Smith, Charles M. Burt, Tracy S. Slavin, Stuart W. Styles, Amir Mansoubi

BioResource and Agricultural Engineering

Seepage losses in the San Joaquin Valley's Westlands Water Districts were estimated at 27,000 acre-feet a year, or about 2% of the district's water supply. Ditch configuration and construction techniques appear to influence seepage rates.