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Articles 67921 - 67950 of 75074
Full-Text Articles in Engineering
Review And Analysis Of Pavement Management Practices In Kentucky, David L. Allen
Review And Analysis Of Pavement Management Practices In Kentucky, David L. Allen
Kentucky Transportation Center Research Report
Pavement Management is becoming increasingly more important in an era of limited budgets and aging pavement structures, State Highway Agencies (SHA) are attempting to manage the pavements under their jurisdiction more carefully and economically. All pavement management systems include all or some of the following items as inputs: (1) pavement distress, (2) serviceability or rideability, (3) inventory of the system, (4) structural adequacy, (5) traffic volumes and loadings, and (6) some form of performance history. This report documents Kentucky's present pavement management system. In addition, the duties and goals of the Pavement Management Branch are catalogged and described. Methods for …
Heat And Momentum Transfer Analogies For The Transitional And Turbulent Flow Of A Non-Newtonian Power-Law Fluid In A Heated Pipe, Prapat Wangskarn, Bahman Ghorashi
Heat And Momentum Transfer Analogies For The Transitional And Turbulent Flow Of A Non-Newtonian Power-Law Fluid In A Heated Pipe, Prapat Wangskarn, Bahman Ghorashi
Chemical & Biomedical Engineering Faculty Publications
A model is proposed for the transfer of heat to non-Newtonian power-law fluids flowing in heated horizontal pipes. Comparisons with the existing models, based on the absolute-percent-arithmetic-average-deviation and the percent-standard-deviation, show that under the transitional and turbulent flow regimes the proposed correlation fits the experimental data more accurately over a wide range of flow behavior index and there are no restrictions for its use when applied to pseudoplastic fluids.
A Numerical Solution For The Turbulent Flow Of Non-Newtonian Fluids In The Entrance Region Of A Heated Circular Tube, Prapat Wangskarn, Bahman Ghorashi, Rama Subba Reddy Gorla
A Numerical Solution For The Turbulent Flow Of Non-Newtonian Fluids In The Entrance Region Of A Heated Circular Tube, Prapat Wangskarn, Bahman Ghorashi, Rama Subba Reddy Gorla
Chemical & Biomedical Engineering Faculty Publications
Numerical solutions of conservation equations are obtained for turbulent flow of non-Newtonian fluids in a circular tube. The forward marching procedure of Patankar and Spalding^1 was implemented in order to obtain the simultaneous development of the velocity and temperature fields by using the apparent viscosity of fluids. Prandtl's mixing length concept is used to determine the apparent turbulent shearing stress. Furthermore, local and average Nusselt numbers are obtained in the entrance region, as well as in the fully developed region. For the case of the fully developed region, values of the Nusselt numbers …
Evaluation Of Wick Drain Stabilization Of Approach Fill Foundation (Bullitt County), Bobby W. Meade, David L. Allen
Evaluation Of Wick Drain Stabilization Of Approach Fill Foundation (Bullitt 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 prefabricated wick drains for dewatering and stabilizing an approach fill foundation. Construction was observed and photologged. Foundation pore pressure was monitored with pneumatic piezometers. Settlement of the entire structure was monitored by use of control points on the retaining wall and pavement.
Construction procedures were acceptable. Wick drains have functioned as expected and the approach fill has been stable for approximately four years since construction.
Investigation Of Premature Cracking On The National Turnpike, Jefferson County, L. John Fleckenstein, R. Clark Graves, David L. Allen
Investigation Of Premature Cracking On The National Turnpike, Jefferson County, L. John Fleckenstein, R. Clark Graves, David L. Allen
Kentucky Transportation Center Research Report
This report discusses the investigation of the premature cracking that occurred on the National Turn pike, Jefferson County (1989). A detailed distress survey was performed evaluating each slab throughout the project site. Falling Weight Deflectometer testing was performed on every third slab. In addition subgrade samples were taken, along with the installation of three water monitoring wells. Laboratory test were conducted on the subgrade samples.
Damage that occurred near the curb inlets and manholes is probably due to insufficient compaction. The remaining damage is most likely related to the combined effects of a very soft subgrade, high water tables, and …
Electrochemical Evaluation Of Copper Deposition With Gas Sparging, D. A. Uceda, Thomas J. O'Keefe
Electrochemical Evaluation Of Copper Deposition With Gas Sparging, D. A. Uceda, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
The influence of gas sparging during copper electrolysis was studied using standard electrochemical techniques. The polarization behavior of acid copper electrolytes was determined in the presence and absence of gas sparging on vertical electrodes. Tracer ion techniques were employed to determine the effect of gas sparging and forced circulation of the electrolyte on the mass transfer characteristics of the system. In addition to the potentiodynamic scans, 3-h copper deposits were produced for morphology and orientation studies. The effect of current density and temperature on deposition were also studied. The polarization experiments have shown that a mass transfer component becomes evident …
The Wic Advisor: A Case Study In Medical Expert System Development, Elizabeth J. Mattson, Matthew M. Thomas, Sharon A. Trenz, Steve B. Cousins
The Wic Advisor: A Case Study In Medical Expert System Development, Elizabeth J. Mattson, Matthew M. Thomas, Sharon A. Trenz, Steve B. Cousins
All Computer Science and Engineering Research
This project provides a good case study of expert system development with untrained experts over a short period of time. We describe the development of a working medical screening and diagnosis expert system for use at the Women, Infants and Children (WIC) clinics in Madison County, Illinois. The system was designed and implemented over the period of four months. A large number of knowledge acquisition techniques were employed, some of them customized in ways that greatly increased their effectiveness. This paper explores the development of THE WIC Advisor, from problem definition through expert system delivery. The knowledge acquisition methods used …
Pneumatic Metering Of Hardwood Tree Seeds, Larry G. Wells, T. W. Richards, Timothy D. Smith, George B. Day
Pneumatic Metering Of Hardwood Tree Seeds, Larry G. Wells, T. W. Richards, Timothy D. Smith, George B. Day
Biosystems and Agricultural Engineering Faculty Publications
A commercial, no-till row planter was extensively modified for use in direct seeding of hardwood tree species in surface mine reclamation. A pneumatic seed metering system was designed, fabricated, and mounted on the planter frame.
The metering device was tested under laboratory conditions which simulated varying terrain slope and field speed with seeds of various hardwood tree species. Metering efficiencies of 97% were achieved for pin oak seeds at 3.2 km/hr (2.0 m/h) and 50% slope. For red oak, 97% efficiency was achieved for 50% slope at 4.0 km/h (2.5 mph). Unsatisfactory metering was noted during tests of larger seeds, …
A Numerical Model For Areal Migration Of Water And Light Hydrocarbon In Unconfined Aquifers, Jagath J. Kaluarachchi, J. C. Parker, R. J. Lenhard
A Numerical Model For Areal Migration Of Water And Light Hydrocarbon In Unconfined Aquifers, Jagath J. Kaluarachchi, J. C. Parker, R. J. Lenhard
Civil and Environmental Engineering Faculty Publications
A finite element model has been developed to simulate simultaneous flow of water and light hydrocarbon in an areal flow region of an unconfined aquifer for analyses of hydrocarbon spreading from subsurface leaks or spills and for use in design of free product recovery systems. Vertically integrated governing equations for water and oil flow are employed which assume local vertical equilibrium and negligible gas pressure gradients. Multiple water and free product recovery wells are handled as internal type-I boundary conditions by stipulating air-oil table elevation and free product height with corrections to convert grid averaged nodal heads to actual well …
Drastic Indices For Selected Agricultural Areas In Utah, Ahmad Yar Ranjha, Richard C. Peralta, Majid Ehteshami
Drastic Indices For Selected Agricultural Areas In Utah, Ahmad Yar Ranjha, Richard C. Peralta, Majid Ehteshami
Civil and Environmental Engineering Faculty Publications
The main objective of this report is to present contour maps of DRASTIC indices for selected areas in Utah. In general, the higher the DRASTIC index value, the greater the potential for ground-water pollution. The acronym DRASTIC is derived from the following hydrogeologic factors which affect vertical movement of water through the soil, and hence affect downward movement of contaminant.
The Policy Process: Cooperation As An Initiative In Utah, Richard C. Peralta, Ann W. Peralta
The Policy Process: Cooperation As An Initiative In Utah, Richard C. Peralta, Ann W. Peralta
Civil and Environmental Engineering Faculty Publications
No abstract provided.
Effects Of Bandwidth‐Limiting Tuning Elements In Synchronously Pumped Mode‐Locked Lasers, Bahram Zandi, Lee W. Casperson, Duncan Leo Macfarlane
Effects Of Bandwidth‐Limiting Tuning Elements In Synchronously Pumped Mode‐Locked Lasers, Bahram Zandi, Lee W. Casperson, Duncan Leo Macfarlane
Electrical and Computer Engineering Faculty Publications and Presentations
A description of bandwidth‐limiting tuning filters is introduced into a semiclassical model for synchronously pumped mode‐locked dye lasers. The finite phase memory of the molecular wave functions is included as are the isotropic molecular distribution and the finite vibrational relaxation times. The new set of equations has been solved numerically using the best available values for the various parameters. The results have been compared with experimental data obtained using a rhodamine 6G dye laser, which is synchronously pumped using an acousto‐optically mode‐locked argon laser. Tuning element effects have been studied using two‐ and three‐plate birefringent filters and a tuning wedge, …
Pulse-Train Instabilities Of A Synchronously Pumped Mode-Locked Dye Laser: Experimental Phase Plots, Duncan Leo Macfarlane, Lee W. Casperson
Pulse-Train Instabilities Of A Synchronously Pumped Mode-Locked Dye Laser: Experimental Phase Plots, Duncan Leo Macfarlane, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
We present experimental phase plots of the pulse-train instability that occurs in synchronously pumped mode-locked dye lasers. From these plots we infer that the instability is of a quasi-periodic, nonlinear dynamical nature. Further, we note that the information lost in this two-dimensional representation is precisely the periodic-versus-erratic character and therefore is of considerable importance.
An Indirect Sensing Technique For Closed-Loop Diesel Fuel Quantity Control, Carl A. Maccarley, Walter D. Clark, Keay T. Nakae
An Indirect Sensing Technique For Closed-Loop Diesel Fuel Quantity Control, Carl A. Maccarley, Walter D. Clark, Keay T. Nakae
Electrical Engineering
Despite significant advances in electronic control technology applied to diesel engines, commercially available injection systems for automotive diesel engines remain limited by the open-loop mapping of the injection pump. An initial calibration is relied upon to translate a fuel delivery command to an actual fuel quantity. In practice, however, these two variables may be substantially different due to the effects of mechanical wear, repair, and the wide range of operating conditions. Possible ramifications of this discrepancy are excessive exhaust smoke due to overfueling, increased fuel consumption, degraded driveability, and poor idle characteristics. The major obstacle to closing the fuel control …
Processing Of One-Fiber Interferometric Fiber-Optic Sensor Signals, A. Tino Alavie, Barry Grossman, Michael Thursby
Processing Of One-Fiber Interferometric Fiber-Optic Sensor Signals, A. Tino Alavie, Barry Grossman, Michael Thursby
Electrical Engineering and Computer Science Faculty Publications
Recent research conducted in the Fiber -Optic Sensor Systems Laboratory at Florida Institute of Technology in fiber -optic strain sensors for use in smart structures has concentrated primarily on one -fiber interferometers. Sensors using this technique are of particular interest because they are rugged and provide reasonable strain sensitivities, typically a thousand times that of microbend sensors, while requiring only a single optical fiber. As in two -fiber interferometers, some method must be used to convert the sensor signal output to an absolute strain value. One technique is to provide active phase tracking to keep the sensor signal output at …
Fiber-Optic Sensor And Smart Structures Research At Florida Institute Of Technology, Barry Grossman, Tino Alavie, Fred Ham, Jorge Franke, Michael Thursby
Fiber-Optic Sensor And Smart Structures Research At Florida Institute Of Technology, Barry Grossman, Tino Alavie, Fred Ham, Jorge Franke, Michael Thursby
Electrical Engineering and Computer Science Faculty Publications
This paper discusses the fundamental issues being investigated by Florida Institute of Technology (F.I.T.) to implement the technology of smart structural systems for DoD, NASA, and commercial applications. Embedded sensors and actuators controlled by processors can provide a modification of the mechanical characteristics of composite structures to produce smart structures1-3. Recent advances in material science have spurred the development and use of composite materials in a wide range of applications from rotocraft blades and advanced tactical fighter aircraft to undersea and aerospace structures. Along with the advantages of an increased strength-to-weight ratio, the use of these materials has raised a …
Acuta Enews February 1990, Vol. 19, No. 2
Acuta Enews February 1990, Vol. 19, No. 2
ACUTA Newsletters
In This Issue
Ohio State's Innovative Technique for Student Resale: Bar-Coding
Message From The President
Winter Seminar in Scottsdale a Success!
Update: Board of Directors Meetings in Scottsdale
News from ACUTA Headquaters
Cable and Wire: The Ties That Bind, Gag and Choke
Telephone Calling Cards Save Travelers Time And Money
The Effects Of Lead On The Electrochemical And Adhesion Behavior Of Zinc Electrodeposits, Vijay Srinivasan, J. Sami Cuzmar, Thomas J. O'Keefe
The Effects Of Lead On The Electrochemical And Adhesion Behavior Of Zinc Electrodeposits, Vijay Srinivasan, J. Sami Cuzmar, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
The presence of excessive lead in zinc sulfate electrolytes can lead to problems related to both processing efficiency and the properties of the metal produced. For example, poor adhesion can occur in electrogalvanized steel when it is heated in the temperature range of 215 °C to 280 °C if lead is present in the deposit. The duration of heating necessary to induce the peeling of the zinc was found to be dependent on the temperature, time, and concentration of lead in the electrolyte and the plating parameters. The presence of lead slowed the formation of the intermetallic, and the peeling …
Ultrasonic Measurement Of The Geometric Parameters Of Gaseous Voids In Low Gravity Fluid Containers, A. T. Patten, William W. Durgin
Ultrasonic Measurement Of The Geometric Parameters Of Gaseous Voids In Low Gravity Fluid Containers, A. T. Patten, William W. Durgin
Office of the Provost Scholarship
A demonstration system for the ultrasonic gauging of fluids in low-gravity has been designed and tested. For purposes of simplification, it was assumed that vapor within a liquid container in low-gravity would form a spherical bubble which would float freely in the container. The project was designed to show that ultrasonic techniques could be used to determine the geometry of the resulting sphere given a worst-case transducer arrangement. The motivation was to simplify transducer mounting requirements so that propellant or other storage vessels could be fitted with ultrasonic gauging systems with a single or perhaps a few transducer penetrations. Data …
Image Preprocessing For Phase- Only Filtering, Samuel Peter Kozaitis, Atikom Roeksabutr
Image Preprocessing For Phase- Only Filtering, Samuel Peter Kozaitis, Atikom Roeksabutr
Electrical Engineering and Computer Science Faculty Publications
We compare the performance of an optical binary phase-only correlator using several nonlinear filters for preprocessing. An image of an airfield with different but similar appearing planes is used as the input data. The performance of the correlator was measured by examining several parameters in the correlation plane. Performance criteria are the signal-to-clutter ratio, the signal-to-noise ratio for objects within the same class, and the variance of the correlation peak within a class. Input images to the correlator were preprocessed using nonlinear filters based on both median filtering and adaptive filtering. The preprocessing improved the performance of the correlator by …
Acuta Enews January 1990, Vol. 19, No. 1
Acuta Enews January 1990, Vol. 19, No. 1
ACUTA Newsletters
In This Issue
Seasoned Pro & Nervous Novice
Message From The President
Make a membership
Working with Vendors
Party Line
Tests Of Full Scale Brick Veneer Steel Stud Walls To Determine Strength And Rain Penetration Characteristics, Michael J. Wilson, A. S. Essawy, A. Kluge
Tests Of Full Scale Brick Veneer Steel Stud Walls To Determine Strength And Rain Penetration Characteristics, Michael J. Wilson, A. S. Essawy, A. Kluge
CCFSS Library (1939 - present)
The design, construction and physical testing of five full scale (2.75 m x 5.2 m) brick veneer rain screen wall specimens are reported. Also, the documentation of the design and fabrication of a new test apparatus and of the development of test procedures are major components of the report. The test program included sequences of air pressure loading stages both with and without simulated rain to establish both the structural and rain penetration performances of the test walls. The test walls included four brick veneer/steel stud specimens and one brick veneer/concrete block specimen. Additional tests were performed on bricks, mortar …
Self-Mode-Locking Of A Semiconductor Laser Using Positive Feedback, Dennis J. Derickson, R. J. Helkey, A. Mar, P. A. Morton, J. E. Bowers
Self-Mode-Locking Of A Semiconductor Laser Using Positive Feedback, Dennis J. Derickson, R. J. Helkey, A. Mar, P. A. Morton, J. E. Bowers
Electrical Engineering
A new mode-locking technique, self-mode-locking, is described which uses the detected optical pulses from the mode-locked laser as the active driving source. This technique forms narrow-width mode-locked optical pulses at low repetition rates without the use of a microwave synthesizer
New Product Performance Evaluation Under Simulated Rain (Part Ii), C. Earl Israelsen, Gilberto Urroz
New Product Performance Evaluation Under Simulated Rain (Part Ii), C. Earl Israelsen, Gilberto Urroz
Reports
Introduction: In January, 1990 a report bearing the same title as this report was prepared and submitted to CONWED Corporation. It contained results from tests performed on experimental erosion control blankets that CONWED was developing. This report provides similar test results of additional new material.
Using Topographic Maps In Extension, Richard C. Warner
Using Topographic Maps In Extension, Richard C. Warner
Agricultural Engineering Extension Updates
Enclosed is an index of available topographic maps, as of September, 1990, which covers the entire state. Most counties will need twelve maps to obtain complete coverage. county agents will find that these maps will significantly aid producers in making decisions about pond locations, drainage, location of structures, elevation differences, slopes, etc. Detailed topographic maps can be obtained from:
- KY Geological Survey
228 Mining & Mineral Resources Bldg.
University of Kentucky
Lexington, Ky 40546-0107 - Eastern Distribution Branch
U.S. Geological Survey
1200 South Eads Street
Arlington, VA 22202 - Western Distribution Branch
U.S. Geological Survey
Federal Center, Box 25286
Denver, CO 80225
Canal Control Training, Charles M. Burt
Canal Control Training, Charles M. Burt
BioResource and Agricultural Engineering
When compared to other industrial processes, irrigation processes are poorly controlled. Due to the unpredictable and uncontrollable nature of many present aspects of irrigation, a high degree of non-transferrability, or "art", is associated with irrigation. The Irrigation Training and Research Center (ITRC) at Cal Poly is dedicated to finding a retirement home for "Art". T
There is a great potential for excellent on-farm irrigation water management. Many tools (center pivots, linear moves, surge irrigation, drip, laser land grading, to name a few) exist to enable farmers to distribute water evenly across their fields. Other tools (computerized irrigation scheduling programs, automated …
Us Army Foreign Science And Technology Center [A Brochure], Robert Bolin , Depositor
Us Army Foreign Science And Technology Center [A Brochure], Robert Bolin , Depositor
United States Department of Defense Military Intelligence
The Foreign Science and Technology Center (FSTC) was a special-purpose intelligence production organization concerned with weapons and equipment of foreign ground forces.
This document is a lengthy, polished brochure giving a general overview of FSTC apparently intended for recruitment purposes. It outlines the mission and function of FSTC and of its subdivisions and gives a thumb-nail sketch of the history of the organization.
Although it is undated, information in the text indicates that it was probably published around 1990.
Physiological Diversity And Distributions Of Heterotrophic Bacteria In Deep Cretaceous Sediments Of The Atlantic Coastal Plain, James K. Fredrickson, David L. Balkwill, John M. Zachara, Shu-Mei W. Li, Fred J. Brockman, Mary Simmons
Physiological Diversity And Distributions Of Heterotrophic Bacteria In Deep Cretaceous Sediments Of The Atlantic Coastal Plain, James K. Fredrickson, David L. Balkwill, John M. Zachara, Shu-Mei W. Li, Fred J. Brockman, Mary Simmons
United States Department of Energy: Publications
A series of 23 intact core segments was obtained from two distinct deep subsurface geological formations, the Middendorf and the Cape Fear formations, underlying the southeastern coastal plain of South Carolina. The Middendorf formation in this region consists of permeable, saturated, sandy sediments; the Cape Fear formation consists mainly of less permeable sediments. The core segments were separated by vertical distances ranging from several centimeters to 48 m. Aerobic chemoheterotrophic bacteria were enumerated on a dilute medium, and populations ranged from 3.1 to 6.4 log CFU g of sediment-1 in the Middendorf cores and from below detection to 4.3 …
Identification Of Solubility-Controlling Solid Phases In A Large Fly Ash Field Lysimeter, Jonathan S. Fruchter, Dhanpat Rai, John M. Zachara
Identification Of Solubility-Controlling Solid Phases In A Large Fly Ash Field Lysimeter, Jonathan S. Fruchter, Dhanpat Rai, John M. Zachara
United States Department of Energy: Publications
Samples of pore fluids and leachates were obtained from a large fly ash field lysimeter in central Pennsylvania. The fly ash in the lysimeter was usually only partially saturated, and only 0.3 pore volumes of water leached through the lysimeter during the 3-year study period. The samples were analyzed for major and trace inorganic anions and cations. The resulting analyses were modeled by using an equilibrium speciation/solubility code to test the hypothesis that the solubilities of at least some species in the fly ash leachate were controlled by solid phases. Potential solubility-controlling solids were identified for Al, Ba, Ca, Cr, …
Influence Of Mineral-Bound Humic Substances On The Sorption Of Hydrophobic Organic Compounds, Ellyn M. Murphy, John M. Zachara, Steven C. Smith
Influence Of Mineral-Bound Humic Substances On The Sorption Of Hydrophobic Organic Compounds, Ellyn M. Murphy, John M. Zachara, Steven C. Smith
United States Department of Energy: Publications
The sorption of three hydrophobic organic compounds (HOC) was investigated on hematite and kaolinite that had been coated with natural humic substances over a mass percent carbon range of 0.01-0.5%. Increasing quantities of sorbed humic substances increased the sorption of HOC. Anthracene, the most hydrophobic HOC, showed the greatest sorption enhancement, while the most aromatic coating, peat humic acid, was the strongest sorbent. Depending on the type of humic acid coating and the mineral substrate, the experimental Koc values were either higher or lower than those predicted by the Kow The sorptivity of a given humic acid for …