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1995 Midnite Mine Radiation Survey

Description: Abstract: During the week of September 4, 1995, personnel from the U.S. Bureau of Mines conducted a Ra-226 survey at the Midnite Mine. One hundred thirty measurements were made on a rectangular grid with 150-m spacings. Concurrently, Shepherd Miller, Inc., took gross gamma readings in gR/h at the same grid points. In addition, the USBM collected 17 soil samples to be analyzed for radium, thorium, and potassium. The results of this survey are summarized in this report.
Date: 1996
Creator: Stroud, William P. & Droullard, Robert F.
open access

3DTOM, Three-Dimensional Geophysical Tomography

Description: Abstract: 3DTOM is a DOS-compatible computer program developed by the Mines U.S. Bureau of for three-dimensional tomographic imaging of the subsurface at mine sites. The program uses the simultaneous iterative reconstruction technique (SIRT) to invert travel- time data and produce maps of wave velocity, or to invert amplitude data and generate maps of wave attenuation coefficients. Either seismic (compressional and/or shear) or electromagnetic (e.g., radio or radar) wave data may be used. Ray t… more
Date: 1996
Creator: Jackson, Michael J. & Tweeton, Daryl R.
open access

An Adaptive System for Process Control

Description: Abstract: Researchers at the U.S. Bureau of Mines (USBM) have developed adaptive process control systems in which genetic algorithms (GA's) are used to augment fuzzy logic controllers (FLC's). GA's are search algorithms that rapidly locate near-optimum solutions to a wide spectrum of problems by loosely modeling the search procedures of natural genetics. FLC's are rule-based systems that efficiently manipulate a problem environment by modeling the "rule-of-thumb" strategy used in human decision… more
Date: 1995
Creator: Karr, Charles L.; Gentry, E. J. & Stanley, D. A.
open access

Adhesion of Diamond Films on Tungsten

Description: The U.S. Bureau of Mines has investigated the chemical vapor deposition of diamond films on tungsten substrates. The effects of deposition parameters on the adhesion of the films was determined. The films were produced using a hot filament chemical vapor deposition system. Parameters investigated were substrate temperature and methane concentration in the feed gas. Film quality, morphology, and composition were characterized by scanning electron microscopy and Raman spectroscopy. Adhesion testi… more
Date: 1995
Creator: Maggs, K. J.; Walkiewicz, J. W. & Clark, A. E.
open access

Application of Field Measurements and Computer Modeling to Evaluate Deep Mine Shaft Stability in Northern Idaho

Description: Abstract: Researchers at the U.S. Bureau of Mines have developed personal-computer-based data acquisition, instrumentation, and mine visualization and modeling techniques to evaluate a mine accessway in a deep hard-rock mine in northern Idaho. These techniques were applied to a mine shaft in a large silver mine that has been in operation for many years. A very deep, rectangular, timber-supported shaft extending to depths exceeding 2.3 km (7,500 ft) had been deforming continuously as a result of… more
Date: 1996
Creator: Beus, Michael J.; Orr, T. J. & Whyatt, J. K.
open access

Bending Fatigue Tests on Flattened Strand Wire Rope at High Working Loads

Description: Abstract: The U.S. Bureau of Mines established a wire rope research laboratory to examine the factors that affect the safety and the useful life of wire rope. In the most recent work, two 32-mm 6x27H flattened strand ropes were degraded on a bending fatigue machine. The two tests were run at constant loads of 285 and 347 kN or safety factors of 2.5 and 2. Nondestructive and tensile strength tests were performed on samples of the ropes to determine the relationship between rope deterioration and… more
Date: 1995
Creator: Wang, Richard C. & Shapiro, David E.
open access

Beneficiation of Iron-Copper Ores from Kasaan Peninsula, Prince of Wales Island, Alaska

Description: Report issued by the Bureau of Mines over studies conducted on the beneficiation of iron-copper ores. As stated in the summary, "this report summarizes the results of laboratory testing of copper-bearing magnetite ore from the Poorman, Rush and Brown, and Copper Center deposits, Kasaan Peninsula, Prince of Wales Island, southeastern Alaska" (p. 1). This report includes tables, maps, and illustrations.
Date: February 1957
Creator: Wells, R. R.; Erspamer, E. G. & Sterling, F. T.
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