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Articles 189781 - 189810 of 196483
Full-Text Articles in Engineering
Field Manual Fm 55-8, Transportation Intelligence, 12 March 1970, Robert Bolin , Depositor
Field Manual Fm 55-8, Transportation Intelligence, 12 March 1970, Robert Bolin , Depositor
United States Department of Defense Military Intelligence
Obviously, reliable information about potential enemy transportation equipment, facilities, systems, capabilities is vital, since our forces may need to prevent an enemy from using them and we may need to use them. Transportation or mobility intelligence is such reliable information. This is a very thorough document describing the collection, production, and dissemination of transportation intelligence. The emphasis of this manual is collection of relevant information in the field.
The manual describes organizations and personnel in the army responsible for collecting transportation related information. It identifies the national-level military intelligence production agencies as:
(a) The Defense Intelligence Agency (DIA) which was …
Electron Emitter Tips And Method, P. D. Ownby
Electron Emitter Tips And Method, P. D. Ownby
Materials Science and Engineering Faculty Research & Creative Works
Boron is deposited on the (110) plane facet at the center of a tungsten electron emitter tip by chemical vapor deposition of boron triiodide. The emission current density is greatest in the center of the emitting area (FIG. 2).
Pavement Slipperiness Studies, James L. Burchett Jr., Ronalds L. Rizenbergs
Pavement Slipperiness Studies, James L. Burchett Jr., Ronalds L. Rizenbergs
Kentucky Transportation Center Research Report
Studies of pavement skid resistance in Kentucky have been in progress since 1956. In 1964, an extensive investigation into the use of an automobile as a testing tool was undertaken and an interim standard method of test was selected. Since then, investigations with the device have continued, both to facilitate meaningful interpretation of skid-test data and to evaluate the skid resistance performance of pavement surfaces.
Variables associated with the testing device, procedures and pavement surfaces were investigated. Several paving projects were tested to determine the number of sites required to obtain a representative result. It was found that on most …
Closed Conduit To Open Channel Usu Stilling Basin, Gordon H. Flammer, Gaylord V. Skogerboe, Chi-Yuan Wei, Hameed Rasheed
Closed Conduit To Open Channel Usu Stilling Basin, Gordon H. Flammer, Gaylord V. Skogerboe, Chi-Yuan Wei, Hameed Rasheed
Reports
Criterion have been developed for designing a stilling basin to serve as a transition from closed conduit flow to open channel flow for a fully submerged pipe outlet. The unique feature of the stilling basin is the short-pipe energy dissipater so located and designed as to provide maximum energy dissipation for the basin configuration. The expanding characteristics of a submerged jet were used in establishing the length of the stilling basin. The unsteadiness of the water surface and the relative boil height in the model basin were used as the criteria for evaluating the effectiveness of the structure for energy …
Hydrologic Inventory Of The Uintah Study Unit, Lloyd H. Austin, Gaylord V. Skogerboe
Hydrologic Inventory Of The Uintah Study Unit, Lloyd H. Austin, Gaylord V. Skogerboe
Reports
The 1963 Utah State Legislature authorized the Utah Water and Power Board (now the Utah Division of Water Resources) to develop a state water plan in order to give coordination and direction to the activities of all state and federal agencies concerned with Utah's water resources. To facilitate the development of this plan, a proposal was submitted through the State Planning Coordinator in the Governor's Office to the Urban Renewal Administration of the Housing and Home Finance Agency. Funding was approved effective May 19, 1966, under the Urban Planning Assistance Program authorized by Section 701 of the Housing Act of …
Interior Corrosion Of Structural Steel Closed Sections, American Iron And Steel Institute
Interior Corrosion Of Structural Steel Closed Sections, American Iron And Steel Institute
CCFSS Library (1939 - present)
A survey of light poles, water-tank stanchions, orthotropic deck bridges, marine tubular catwalks, davits and welded steel columns strongly suggests, contrary to some beliefs, that interior surfaces of closed steel sections rust but little in the atmosphere, even when not fully sealed. Only light rusting occurs because amounts of oxy'gen and water in entrapped air are limited and condensation necessary for rusting is infrequent. Computations based on the oxidation reaction taking into account inside surface, volume of entrapped air, relative humidity and air changes show that the loss of iron thickness due to such rusting is negligible. Use of closed …
Freeze-And-Thaw Phenomena In Concretes And Aggregates, James H. Havens
Freeze-And-Thaw Phenomena In Concretes And Aggregates, James H. Havens
Kentucky Transportation Center Research Report
This report summarizes several years of research relating to damage to concrete and aggregates undergoing freezing and thawing. Basic principles involving freezing and attendant pressures are considered. Application of these principles to the evaluation of concrete was accomplished in experiments on concrete having low and high air contents. The effects of air entrainment upon freeze-thaw resistance were demonstrated.
Freeze-thaw characteristics of saturated aggregates relative to their physical properties such as porosity, absorption and bulk specific gravity were studied by submerging individual particles in pre-chilled mercury. Pressures associated with popouts in concrete were monitored and are presented along with accompanying theoretical …
An Investigation Of Low-Strength Concrete And Resulting Structural Failure In A Bridge Deck, James H. Havens
An Investigation Of Low-Strength Concrete And Resulting Structural Failure In A Bridge Deck, James H. Havens
Kentucky Transportation Center Research Report
This investigation concerns the discovery of weak concrete in a portion of the deck of the Elkhorn City bridge, APD 640(4), within a year after it was opened to traffic. The deck concrete was placed between April 14 and June 14, 1968. The bridge serves heavy coal-trucks traffic. Failures occurred in the eastern-most span (No. 5) in April or May of 1969, Undoubtedly, the heavy loading contributed to early disclosure of defective concrete.
A preliminary investigation was made in May 1969, and reported by memorandum May 21, 1969. The bottom third or half of concrete in the affected portion, Span …
Locating And Tracing Seepage Water In Unstable Slopes, Yasin A. Alkhoja, Gordon D. Scott
Locating And Tracing Seepage Water In Unstable Slopes, Yasin A. Alkhoja, Gordon D. Scott
Kentucky Transportation Center Research Report
With the increase in modern highway construction, the occurrence of landslides has been growing proportionally due to the use of deeper cuts and higher fills. It has been observed that landslides on highways often occur in fills on hillsides. Accumulation of water in the embankment, usually seeping from a nearby hill, may reduce the shear strength of the embankment soil and result in failure at a later time. Many landslides on Kentucky highways have occurred a few years after construction and obviously have been caused by the gradual weakening of the embankment due to a damming and accumulation of water. …
Slip-Form Paving, Kerry P. Magan
Slip-Form Paving, Kerry P. Magan
Kentucky Transportation Center Research Report
The proper placement, consolidation, and finishing of low-slump concrete without the aid of pre-erected side, forms has been widely acclaimed as an economical and effective procedure in the construction of portland cement concrete pavements. This construction procedure, commonly referred to as slip-form paving, depends upon the ability of low-slump concrete to remain in place after consolidation and removal of forms.
Slip-form pavers differ from conventional pavers in that no fixed side forms are required inasmuch as the slip-form paver has side forms that advance with the machine. Concrete is merely deposited on the prepared subgrade in front of the machine, …
Final Performance Report On Experimental Use Of Thermoplastic Pavement-Striping Materials, Assaf S. Rahal, Ronald D. Hughes
Final Performance Report On Experimental Use Of Thermoplastic Pavement-Striping Materials, Assaf S. Rahal, Ronald D. Hughes
Kentucky Transportation Center Research Report
This study was undertaken in order to: 1) evaluate the performance of thermoplastic striping materials, 2) compare their performance on both portland cement concrete and bituminous concrete pavements to that of conventional traffic paints, and 3) to evaluate the economics of thermoplastics in terms of cost per mile per day of useful life. The performance of two brands of thermoplastic striping materials and conventional traffic paints applied at nine test sites in both rural and urban areas is reported herein. Application procedures, site locations, repair histories and materials specifications are included. Accumulative costs for each material at all sites for …
Slurry Seal Maintenance Applications, Robert L. Florence, Herbert F. Southgate
Slurry Seal Maintenance Applications, Robert L. Florence, Herbert F. Southgate
Kentucky Transportation Center Research Report
A slurry seal mixture consists of graded fine aggregate (normally minus 3/8-inch material), mixing grade emulsified asphalt (SS-1 or SS-lH), and water. The water is added to aid in mixing and to provide a free-flowing consistency so that the mixture can be spread in thin layers on the surface of an existing pavement. After the mixture is spread, the water evaporates and the remaining material, aggregate and base asphalt, forms a thin seal on the pavement surface which resembles a fine-grained asphaltic-concrete surface. As a result of the free-flowing consistency and the fineness of the aggregate, a slurry mixture readily …
Fluid Friction Reduction By Water Soluble Linear High Polymers, Arthur Edward Davis
Fluid Friction Reduction By Water Soluble Linear High Polymers, Arthur Edward Davis
Theses
The effects of various dilute aqueous linear high polymer solutions on turbulent pipe flow were studied to determine the polymer most suitable for testing as the drag reducing component in the proposed coating. Results of this study are presented for commercial schedule 40 1/4 inch NPS black iron pipe. Tests were conducted at Reynolds numbers of 6.2x104,8.3x104 and 9.8x104.
Attempts were made to prepare a coating containing a friction drag reducing polymer - Polyhall 295 polyacrylamide - utilizing various techniques of polymer incorporation into the paint including several grinding and dispersion methods, adding the polymer …
Commentary On The 1968 Edition Of The Specification For The Design Of Cold-Formed Steel Structural Members, George Winter
Commentary On The 1968 Edition Of The Specification For The Design Of Cold-Formed Steel Structural Members, George Winter
American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)
No abstract provided.
Proceedings Of The International Symposium On Low Cost Housing Problems Related To Urban Renewal And Development, Oktay Ural
International Symposia on Low Cost Housing Problems
PREFACE TO SECOND EDITION--We are very happy to have a second printing of the Proceedings of the First International Symposium on Low-Cost Housing Problems Related to Urban Renewal and Development. The rather quick and large demand of this publication proved to us, once more, the importance and timeliness of the concern on the topic of housing technology and production. The contributions from eighteen nations painted a real picture of housing conditions and needs around the world.
The fifty-one technical papers included in this volume have been selected intentionally in various aspects of housing to draw a complete and meaningful picture …
Column Research Council: Proceedings 1970, Column Research Council
Column Research Council: Proceedings 1970, Column Research Council
CCFSS Library (1939 - present)
The purposes of Column Research Council are to study and discuss problems related to the stability and strength of metal compression members; to organize research in this field; to disseminate information; and to formulate design rules for consideration by specification-writing bodies. The activities of the Council in 1970 are summarized in this report. A particular feature is the Proceedings of the 1970 Annual Technical Session. As in the past, the rosters of members of the Council and the By-Laws are also included. The support and technical contributions of the members and investigators are sincerely appreciated. Those individuals and organizations that …
Effects Of Cold Work In Cold-Formed Steel Structural Members, S. J. Britvec, Alexander Chajes, K. W. Warren, Jairo Uribe, George Winter
Effects Of Cold Work In Cold-Formed Steel Structural Members, S. J. Britvec, Alexander Chajes, K. W. Warren, Jairo Uribe, George Winter
CCFSS Library (1939 - present)
No abstract provided.
Influence Of Ductility On The Structural Behavior Of Light-Gage Cold-Formed Steel Members, A. K. Dhalla, George Winter, S. J. Errera
Influence Of Ductility On The Structural Behavior Of Light-Gage Cold-Formed Steel Members, A. K. Dhalla, George Winter, S. J. Errera
CCFSS Library (1939 - present)
Ductility parameters defined in the second progress report were previously obtained by conducting tension coupon tests on specially produced A and S steels. In this report, tension coupon test results are presented for a 20 gage commercial low ductility steel, i.e. an ASTM Grade E steel, herein designated as steel B. Its behavior is compared with that of the specially rolled A and S steels to test the validity of conclusions arrived at in the second progress report. Test programs were set up to study the behavior of B steel under static tension loading, one program for single bolted connections …
Systems Reliability Using The Flow Graph, Kenneth Edward Farrier
Systems Reliability Using The Flow Graph, Kenneth Edward Farrier
Dissertations and Theses
The problem of calculating the reliability of a complex system of interacting elements is delineated to a linear system, no element of the system having a reliability distribution in terms of any other e1ement of the system, where only one path is taken through the system at a time. A precise definition is then developed to specify the reliability of the linear, single path at a time, system. A precise and concise generating function is found that effortlessly produces the reliability of the linear, single path at a time, system directly from the reliability flew graph of the system.
Case Study And Analysis Of A Low Cost Housing Project In An Urban Area In India, P. Purusothaman, Jawalker K. Sridhar Rao
Case Study And Analysis Of A Low Cost Housing Project In An Urban Area In India, P. Purusothaman, Jawalker K. Sridhar Rao
International Symposia on Low Cost Housing Problems
An urban development project involving residential and school buildings as an extension of Madras city is described. The analysis of the project is made using the systems approach as a problem of human settlements. The methods adopted for efficient utilisation of space at optimal cost by functional planning, use of prefabricated units and use of new constructional procedures is described. The interrelationship between environmental, technical, social, cultural, psychological, economic, financial and management factors in making decisions for the project is discussed.
A Case For University Credits For Industry's In-House Continuing Education Programs, Robert E. Carlile
A Case For University Credits For Industry's In-House Continuing Education Programs, Robert E. Carlile
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The minerals industries have long recognized the tangible and intangible returns from continuing education programs for their technical scientific and administrative personnel. These programs originate from the mutual desires of the employer to upgrade the professional competence of the employee and the employee's concurrent desires to keep abreast of new developments to review the state of the art of specialized subjects and to better qualify himself to compete in an every changing technology. In-house training and continuing education programs to provide such review and education for the employee are becoming a recognized function of companies comprising this industry. These company-sponsored …
A Theory On Interpreting Engine Noises, Robert C. Erickson
A Theory On Interpreting Engine Noises, Robert C. Erickson
Undergraduate Student Work
Mechanics have always used sounds to "trouble shoot" an engine. To a trained ear, each sound is different. Since an ear can be this sensitive, this paper will attempt to prove that electronic equipment can be considerably more accurate in detecting engine problems. The writer of this paper has attempted a project in which he hopes to prove that valve and bearing problems can be located by studying oscilloscope displays. These displays would picture the sound frequencies of valve and bearings in operation. The writer assumed that a comparison could be made of the displays of a normal engine operation …
Test 1058: Case 770 Power Shift Diesel, Nebraska Tractor Test Lab
Test 1058: Case 770 Power Shift Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
A History Of Maine Roads 1600 - 1970, State Highway Comission
A History Of Maine Roads 1600 - 1970, State Highway Comission
Maine Collection
A History of Maine Roads 1600 - 1970.
State Highway Commission, Augusta, Maine, 1970.
Sections: Two Transportation Firsts, Early Roads, The Stagecoach Arrives, Steamboats and Railroads, Better Roads Movement, The Automobile, State Roads, First Highway Commissioner, State Highway Department, State Highway Commission, Patrol Maintenance, Bridge Law, Federal Aid, Highway Finances, World War 1, First Route Markers, Traffic Counts, Snow and Ice Control, Planning Activities, World War 2, The Maine Turnpike, Right of Way, Division Offices, Chairman Full-Time Position, Engineering Tools and Techniques, Engineering Pioneers, The Interstate Program, Roadside Beauty, Highway Safety, Operation of the Department Today.
The Proposed Eastern Nebraska International Airport Plan, George T. C. Peng, Joseph H. Bain
The Proposed Eastern Nebraska International Airport Plan, George T. C. Peng, Joseph H. Bain
Nebraskiana Publications: Resources and Materials on the 37th State
Excerpt from the prologue:
Passenger growth has led to expansion of facilities at both the Omaha and Lincoln airports; but like many others in the nation, they are rapidly becoming congested. The Federal Aviation Administration, the State Government officials, and many civic leaders in Nebraska are now becoming aware of the need for establishing a regional airport for the Eastern Nebraska region in order to promote and handle international air transportation for the future. People are also beginning to think of such a modern airport as an essential factor in bringing new industries to Nebraska and in shaping the urbanization …
Test 1045: International Farmall 826 Diesel (Also International 826 Diesel), Nebraska Tractor Test Lab
Test 1045: International Farmall 826 Diesel (Also International 826 Diesel), Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Initial Operation And Calibration Of The Umr Supersonic Axisymmetric Wind Tunnel, James Riley Murphy
Initial Operation And Calibration Of The Umr Supersonic Axisymmetric Wind Tunnel, James Riley Murphy
Masters Theses
"Initial testing and a preliminary calibration were conducted in the UMR supersonic variable Mach number axisymmetric blowdown wind tunnel facility. During initial operations problems were encountered with control valve seat failure, control valve response and stability, and automatic operation. After having brittle fracture failures with seats made of nylon, Teflon and Telfon-copper composite, a copper seat was found to perform satisfactorily with minimal valve leakage. Control valve response and stability were greatly influenced by the setting of the needle valve located between the total pressure probe and the controller. The needle valve setting was observed to depend upon the stagnation …
Measurement Of The Surface Energy Of Rock By The Three-Point Bending Of Notched Beams, John Walter Corwine
Measurement Of The Surface Energy Of Rock By The Three-Point Bending Of Notched Beams, John Walter Corwine
Masters Theses
"In this investigation, the surface energy of a medium-grained igneous rock (Barre granite) was measured by breaking small, notched beams in bending. The technique was adapted from fracture toughness tests that have been used with metals and ceramics. The equations used for the calculation of surface energy were derived from several writers' equations for the stress intensity at the end of a notch in a beam subject to bending. Beam thickness, notch width and mineral occurring at the notch tip were evaluated for their influence on the calculated values of surface energy. The surface energy values obtained were used in …
Investigation Of The System Al₂O₃-Teo₂-O₂, Vera Zelenkova Sestak
Investigation Of The System Al₂O₃-Teo₂-O₂, Vera Zelenkova Sestak
Masters Theses
"The system Al₂O₃-TeO₂-O₂ has been investigated by X-ray diffraction and differential thermal analysis in air and in sealed silica ampoules. The tellurate, Al₂TeO₆, with tellurium in the +6 valence state, forms in air but not in vacuum at 1 mm pressure. A second phase, a tellurite, possibly Al₂Te₂O₇, forms in air or vacuum by devitrification. The glass-forming region is wider than previously stated and is more extensive in vacuum--from 50% to 98% TeO₂. Tentative phase boundaries have been placed for the system in air and vacuum"--Abstract, page ii.