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Articles 70141 - 70170 of 75015
Full-Text Articles in Engineering
Energy In Agriculture: Energy Resource Series For Youth And Adult Energy Programs: 4. Coal, George M. Turner
Energy In Agriculture: Energy Resource Series For Youth And Adult Energy Programs: 4. Coal, George M. Turner
Agricultural Engineering Energy Series
Coal is very close kin to the other fossil fuels, oil and gas. If a chunk of coal is examined with a powerful magnifying glass you will notice a lot of red and gold color. The marks of plants can be plainly seen on many pieces. The imprint of plants and sometimes of animal skeletons indicates to skilled scientists how coal was formed.
Explicit Determination Of Thickness Of A Transparent Film On A Transparent Substrate From Angles Of Incidence Of Equal P And S Reflectivities, R. M.A. Azzam
Electrical Engineering Faculty Publications
No abstract provided.
Modes Of A Laser Resonator With A Retroreflecting Roof Mirror, Guosheng Zhou, Lee W. Casperson
Modes Of A Laser Resonator With A Retroreflecting Roof Mirror, Guosheng Zhou, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
The self-consistent integral equation for the field distribution of the resonant modes in a resonator with a tilted retroreflecting roof mirror is solved. The field distribution in the direction of the roof can be described in terms of Hermite-Gaussian functions. The beam matrix for a retroreflecting roof is found, and a new type of resonator which does not need precise alignment is proposed.
Vegetative Filter Treatment Of Livestock Feedlot Runoff, Elbert C. Dickey, D. H. Vanderholm
Vegetative Filter Treatment Of Livestock Feedlot Runoff, Elbert C. Dickey, D. H. Vanderholm
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Four vegetative filters were installed on feedlots in central and northern Illinois. Two configurations were used: channelized Dow and overland Dow. After settling for partial solids removal, runoff was applied directly to the filters and allowed to Dow from the inlet to the outlet section. Results from measurement analyses and sampling of influent, effluent, and surface Dow at intermediate points were reported.
Most runoff events were infiltrated completely, resulting in no filter discharge. Runoff from larger events was partially discharged. Filters removed as much as 95% of nutrients and oxygen-demanding materials from the applied runoff on a weight basis, and …
Trailer Hitch, T. Richard Robe
Trailer Hitch, T. Richard Robe
Mechanical Engineering Faculty Patents
The present invention is directed to a trailer hitch for a vehicle. The trailer hitch is designed to be connected to a vehicle and permits two degrees of freedom for the hitchpoint. The first degree of freedom is in a lateral direction which permits the hitchpoint to have freedom to move horizontally in a lateral direction. This degree of freedom is dampened by a viscous dampener to improve the lateral stability of a trailer connected to the hitchball. Further, springs are provided to resist lateral movement and to restore the hitchpoint to its original position during the pulling of a …
Energy In Agriculture: The Use Of Ethanol As An Unmixed Fuel For Lnternal Combustion Engines, Joseph L. Taraba, George M. Turner, Robert Razor
Energy In Agriculture: The Use Of Ethanol As An Unmixed Fuel For Lnternal Combustion Engines, Joseph L. Taraba, George M. Turner, Robert Razor
Agricultural Engineering Energy Series
The use of ethanol (ethyl alcohol) as a fuel for spark ignited (Sl) internal combustion engines has been evaluated and considered satisfactory since the early1 900s. Today due to the increasing cost of petroleum and the current world oil uncertainty, which may greatly affect the future availability of petroleum, some alternative fuels for internal combustion engines are needed. Ethanol is one of the fuels that has shown promise as a petroleum substitute. Today the country of Brazil has chosen a path of less dependence on petroleum by developing an ethanol fuel technology. In the spring of 1980, cars designed to …
Identification, Analysis, And Correction Of High-Accident Locations In Kentucky, Charles V. Zegeer, Kenneth R. Agent, Ronalds L. Rizenbergs
Identification, Analysis, And Correction Of High-Accident Locations In Kentucky, Charles V. Zegeer, Kenneth R. Agent, Ronalds L. Rizenbergs
Kentucky Transportation Center Research Report
The first step in the highway safety improvement process involves reporting and summarizing accidents by location. Once the high-accident locations are identified, field investigations and analysis follow. Locations are ranked on the basis of potential for accident reduction. Safety improvements are then scheduled and implemented. Finally, improvements are evaluated in terms of accident reduction.
This report compiles, in detail, the process involved in arriving at safety improvements in the high-accident spot-improvement program. References are made to information and methodologies developed in earlier reports by the Division of Research of the Kentucky Department of Transportation. Most of the background information and …
Design Guide For Bituminous Concrete Pavement Structures, James H. Havens, Robert C. Deen, Herbert F. Southgate
Design Guide For Bituminous Concrete Pavement Structures, James H. Havens, Robert C. Deen, Herbert F. Southgate
Kentucky Transportation Center Research Report
To determine pavement thicknesses from design charts and tables, it is necessary to know only the EAL's (equivalent axle loads), the CBR of the subgrade soil, and the modulus of elasticity of the bituminous concrete. Charts permit selection of pavement structures employing alternative proportions of bituminous concrete and crushed stone base. Total thickness varies according to the proportions chosen. It is implicitly intended that the selection of alternative structures be based on engineering considerations, such as 1. estimates of comparative construction costs, 2. compatibility with cross section template and shoulder designs, 3. uniformity or standardization of design practices, 4. highway …
Analysis Of Time-Deflection Consolidation Data, E. Gregory Mcnulty
Analysis Of Time-Deflection Consolidation Data, E. Gregory Mcnulty
Kentucky Transportation Center Research Report
A computerized statistical curve-fitting algorithm has been developed for determining the time-dependent properties of conventional (load-incremental) consolidation test data. Analytical models of the graphical methods developed by Taylor and Casagrande and of the Naylor-Doran method of successive approximations determtne values for the coefficients of consolidation, permeability, and the values of deflection corresponding to the begimltng and endtng of primary consolidation. The coefficients of volume change and secondary compression are also calculated. A modified statistical definition is used to select the linear portions of the data curves and is applicable to other data-fitting problems. After the Naylor-Doran method has been used, …
Structural Capacity Of In-Place Asphaltic Concrete Pavements From Dynamic Deflections, Herbert F. Southgate, Gary W. Sharpe, Robert C. Deen, James H. Havens
Structural Capacity Of In-Place Asphaltic Concrete Pavements From Dynamic Deflections, Herbert F. Southgate, Gary W. Sharpe, Robert C. Deen, James H. Havens
Kentucky Transportation Center Research Report
The proper design of asphaltic overlay thicknesses involves four major factors; the in-place modulus of the subgrade, an estimate of the structural capacity of the existing pavement, estimates of the future traffic expressed as equivalent axleloads and required or desired design levels, and a thickness design procedure. This paper deals with estimating the in-place subgrade modulus and the remaining load-carrying capacity of the existing pavement. The method presented herein is valid for any Road Rater or other dynamic tester such as the Dynaflect. This procedure was based upon a 600-pound (272.4-kg) peak-to-peak dynamic load applied at a rate of 25 …
Identification Of Kentucky Shales, Tommy C. Hopkins, Brian C. Gilpin
Identification Of Kentucky Shales, Tommy C. Hopkins, Brian C. Gilpin
Kentucky Transportation Center Research Report
Results obtained from a series of engineering tests performed on 40 different types of shales are summarized and discussed. Both hard and soft shales, as well as shales having well-documented histories of involvement in highway embankment failures and shales having little known involvement, were tested. A major portion of the report examines the suitability of the slake-durability tests, originally devised by Franklin-Chandra of England, as a means of broadly characterizing the engineering properties of Kentucky shales. Results obtained from ten different slake-durability testing procedures, which include procedures proposed by Franklin and Chandra and others as well as procedures devised during …
Electromagnetic Modes Of An Inhomogeneous Sphere, Lee W. Casperson
Electromagnetic Modes Of An Inhomogeneous Sphere, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
In many cases the electromagnetic modes of a sphere can be obtained exactly. Special simplifications occur when the conductivity, complex permittivity, and complex permeability vary only in the radial direction, and static and time dependent examples are discussed. With quadratic or Coulomblike permittivity variations, the wave functions resemble the quantum mechanical harmonic oscillator or hydrogen atom wave functions, and similar angular momentum operators are obtained.
Evaluation Of Rumble Strip Design And Usage, Jerry G. Pigman, Michael M. Barclay
Evaluation Of Rumble Strip Design And Usage, Jerry G. Pigman, Michael M. Barclay
Kentucky Transportation Center Research Report
The objective of this study was to investigate the following aspects of rumble strips: the optimum height and width of elements in a rumble strip pattern, spacing between them, the effect of grouping elements into sets, the effects of speed on design criteria, and driver reaction to the audible and physical stimuli produced by rumble strips. A survey of design and usage in other states was conducted; and the results show that even though 35 of the 44 responding states have installed rumble strips, only five have warrants for usage.
Two types of rumble strip design were evaluated -- one …
Evaluation Of Watertight Bridge Expansion Joints, Wm. Vernon Azevedo
Evaluation Of Watertight Bridge Expansion Joints, Wm. Vernon Azevedo
Kentucky Transportation Center Research Report
Engineers have long recognized the importance of bridge expansion joints. The inadequacy in design of such joints has also been realized. Proprietary products are now available which may eliminate well-documented problems associated with bridge expansion.
The objective of this study was to evaluate the field performance of such products.
Vehicle Noise Emission Levels In Kentucky, Kenneth R. Agent
Vehicle Noise Emission Levels In Kentucky, Kenneth R. Agent
Kentucky Transportation Center Research Report
The objectives of this study were to update individual vehicle noise data taken in previous years in Kentucky and to determine reference mean energy emission levels for Kentucky vehicles for use in the SNAP 1 noise prediction procedure.
Comparison of Kentucky and nationwide emission levels showed a close agreement for medium and heavy trucks; however, automobile noise levels in Kentucky were higher than nationwide levels. An analysis of emission levels of the various vehicle types showed that a fourth category, light trucks, may need to be added. The Kentucky emission levels were input into SNAP 1 in place of the …
Synthesis Of Gaussian Beam Optical Systems, Lee W. Casperson
Synthesis Of Gaussian Beam Optical Systems, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
Systematic procedures are presented for determining the the optical components needed to obtain an arbitrary transformation of a propagating light ray or Gaussian beam.
Identification And Rehabilitation Of High-Risk Drivers, Kenneth R. Agent
Identification And Rehabilitation Of High-Risk Drivers, Kenneth R. Agent
Kentucky Transportation Center Research Report
This report deals with the identification and rehabilitation of high-risk drivers. Methods used to identify negligent drivers were examined. Kentucky's point system was compared to those tn other states. The consequences of drivers attending driverimprovement clinics were studied by analyzing driving records.
The analysis showed that accident involvement was directly related to the accumulation of penalty points and number of violations. Definite relationships were found between several specific types of violations and accidents.
A very significant improvement in driving records was noted for those drivers who completed a driver-improvement clinic; however, a similar improvement occurred for drivers eligible for the …
The Impact Of A Computerized Conferencing System On Scientific Research Communities, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz
The Impact Of A Computerized Conferencing System On Scientific Research Communities, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz
Computerized Conferencing and Communications Center Reports
The author is indebted to Murray Turoff for coauthoring the sections describing the EIES system and for his suppport and encouragement for this study at all stages. Mary Anne Solimine served as a research assistant, supervising the distribution, coding and tabulations of questionnaire responses. Without her diligent efforts, the study would not have been possible. Ann Marie Rabke, Joanne Garofalo, Diane Price, Duchess Brooks, Margaret Wnorowski, Christine Naegle, Sonia Khalil, and Marion Whitescarver provided valuable assistance with coding and data entry and editing tasks. Larry Landwebber was most cooperative in providing access to the Theory Net group. Alan Leurck, Thomas …
Ohio River Suspension Bridges: An Inspection Report, Theodore Hopwood Ii
Ohio River Suspension Bridges: An Inspection Report, Theodore Hopwood Ii
Kentucky Transportation Center Research Report
For many years, suspension bridges have been employed to economic advantage where long uninterrupted spans were required. While they have been supplanted for most common applications by cantilever and arch bridges in the United States, suspension bridges are a valid design type. Two American suspension bridges have been in service for over 100 years. A new form of suspension bridge, the cable-stayed bridge, is widely used in Europe and is expected to be as popular in the United States.
The key to the success of suspension bridges lies in the use of high-strength wires that are consolidated into the main …
Traffic Accidents In Kentucky (1978), Kenneth R. Agent
Traffic Accidents In Kentucky (1978), Kenneth R. Agent
Kentucky Transportation Center Research Report
Highway locations having an abnormal history of accidents should be identifiable in some way. Average and critical accident numbers and rates must be known for similar locations. Averages have been determined previously for rural highways, but it is necessary to update those numbers and to determine rates for urban areas. A detailed picture of traffic accidents in Kentucky in 1978 is presented.
Average rates in terms of accidents per 100 million vehicle-miles (160 million vehicle-kilometers) were calculated for various classifications of rural and urban highways. Also, average rates in terms of accidents per million vehicles were determined for 0.3-mile (0.48-km) …
Evaluation Of Raised Pavement Markers In Kentucky: Statewide Installations; 1975-1979, Jerry G. Pigman, Kenneth R. Agent, Rolands L. Rizenbergs
Evaluation Of Raised Pavement Markers In Kentucky: Statewide Installations; 1975-1979, Jerry G. Pigman, Kenneth R. Agent, Rolands L. Rizenbergs
Kentucky Transportation Center Research Report
Raised markers have become commonplace in delineation on highways in states where snowfall is minimal and snowplows are not needed. They have proven to be especially effective for wet, nighttime, and other poor visibility conditions when paint stripes are least effective. In Kentucky, over one million raised markers have been installed and damage from snowplowing has been significant during some of the more severe winters. As a result of costs associated with replacing damaged markers and requirements of the Pavement Marking Demonstration Program, an evaluation of all installations was undertaken.
Between 1975 and 1979, a total of 1,082,250 markers were …
Strain-Rate Selection In The Constant-Rate-Of-Strain Consolidation Test, C. Thomas Gorman
Strain-Rate Selection In The Constant-Rate-Of-Strain Consolidation Test, C. Thomas Gorman
Kentucky Transportation Center Research Report
Constant-rate-of-strain (CRS) consolidation tests were performed on remolded kaolinite specimens. The effect of strain rate on CRS test data is shown. A relation between soil parameters and strain rate was developed and used to formulate a strain-rate selection procedure. The fmal selectlon procedure is based on liquid limit and initial degree of saturation of the specimen and is presented in graphical form. The procedure is applicable to all types of soils.
Mound Sewage Waste Treatment Systems, Elbert C. Dickey, Phillip W. Harlan, Cheryl Kisling-Crouch
Mound Sewage Waste Treatment Systems, Elbert C. Dickey, Phillip W. Harlan, Cheryl Kisling-Crouch
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Several areas in Nebraska are not appropriate for onsite home sewage treatment using conventional septic tank absorption field systems. Site factors that limit the use of conventional absorption fields include slowly permeable soils, shallow or gravelly soils and high water tables. The septic tank-mound system, which consists of a septic tank for primary sewage treatment and a constructed mound for final waste treatment was developed to overcome these site limitations (Figure 1).
Although mound systems differ only slightly in principle from conventional sewage systems, they allow the user to select suitable materials to build an absorption field that relies …
A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee
A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee
Electrical and Computer Engineering Faculty Publications
The present thesis attempts to give a concise and critical account of the evolution of the echo phenomena over the last thirty years. Starting with spin and photon echoes, which were among the earliest to be observed and studied, the thesis explores the experimental findings and the models proposed in connection with the more contemporary echo experiments, viz. those involving electroacoustic or polarization echoes in single and polycrystalline piezoelectric materials and in powders. Although the investigations regarding the various mechanisms of short and long term echo formation are by no means complete, a coherent picture is beginning to emerge as …
Problem Identification For Highway Safety Plan (Fy 1982), Jerry G. Pigman, Kenneth R. Agent, Joseph D. Crabtree
Problem Identification For Highway Safety Plan (Fy 1982), Jerry G. Pigman, Kenneth R. Agent, Joseph D. Crabtree
Kentucky Transportation Center Research Report
To comply with Section 402, Title 23 of the United States Code, each state is required to prepare an annual highway safety program. Kentucky's program, which includes identification, programming, budgeting, and evaluation of highway safety projects, is intended to have a positive impact on the reduction of traffic accidents. The first step in the program, problem identification, requires systematic, statistical analyses of accident records. In-depth analyses of accident data were performed, and 24 problem areas were investigated. Accident rates were found for counties and cities in the following categories: total accidents; fatal accidents; accidents by driver age and sex; and …
County Storm Drainage Manual 1981, Christopher B. Burke
County Storm Drainage Manual 1981, Christopher B. Burke
Indiana Local Technical Assistance Program (LTAP) Publications
This manual is a comprehensive catalog of procedures, design methods and criteria, and general background information which will enable the designer to quickly learn or review the basic principles of storm drainage design. Subjects included are the precipitation and hydrological cycle, runoff and its estimation, open channels, flow in gutters and inlets, stormwater storage, and storm sewer system design. Included in the appendices are basics of statistical analysis, fundamentals of hydraulics, and a list of regulatory agencies and governmental bodies which may have jurisdiction over drainage projects.
The Effect Of Adhesive Bond Strength Of Selected Species Of Laminated Wood, Daniel L. Henderson
The Effect Of Adhesive Bond Strength Of Selected Species Of Laminated Wood, Daniel L. Henderson
Graduate Research Papers
Wood laminating has been used by man for centuries and is a very important part of industrial enterprises today. In most woodworking textbooks reviewed however, those sections devoted to wood laminating are typically miniscule. Topics are hastily covered and only general information is provided. This study has been conducted in order to provide more adequate explanation of the laminating process in addition to those presently available and to explore the interrelationship of laminated components with the ultimate function of the product. A glance at any furniture manufacturing or construction industry periodical, however, will show the importance of wood laminating in …
Modes Of A Laser Resonator With A Retroreflective Mirror, Guosheng Zhou, Lee W. Casperson
Modes Of A Laser Resonator With A Retroreflective Mirror, Guosheng Zhou, Lee W. Casperson
Electrical and Computer Engineering Faculty Publications and Presentations
The self-consistent integral equation for the field distribution of the resonant modes in an inclined retroreflective grating resonator is solved in the limit of large Fresnel numbers. The transverse field distribution in the direction perpendicular to the grating grooves can be described in terms of Hermite-Gaussian functions provided that λ « d « w, where λ is the wavelength, d is the grating spacing, and w is the beam spot size.
Conduction Polarization In Sodium Germanate Glasses, Akira Doi, D. E. Day
Conduction Polarization In Sodium Germanate Glasses, Akira Doi, D. E. Day
Materials Science and Engineering Faculty Research & Creative Works
Only one thermally stimulated depolarization current (TSDC) peak was found in germanate glasses containing from 0.19 to 32.5 mol% Na20, whereas comparable silicate glasses exhibit two such peaks. Equations are developed showing that the distortion of the equilibrium Na+-ion distribution by an applied electrical field produces a polarization in general agreement with the observed TSDC peak. It is proposed that the TSDC peak is due to dc conduction.
Computerized Twist Drill Selection For Cast Iron And Steel, Clinton K. Orth
Computerized Twist Drill Selection For Cast Iron And Steel, Clinton K. Orth
Graduate Research Papers
The science of hole making can hardly be considered new to modern day industry. Evidence of drilling dates back as early as 4000 B.C. However, computers are considered relatively new to industry and their use is growing rapidly. One of the major concerns of industry is to identify a consistent method of selecting the proper drill when given a set of variables. The problem is to identify the sets of variables and select a drill that will give consistent results.