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By Ovsei Volberg

Motion capture involves recording the position and global orientation of joint sensors of a real object, in most cases a real person performing some human activities. This information is usually recorded at uniformly spaced instances of time, or as it is often called frame-by-frame. Then the recorded motion data sets are processed and mapped into a skeleton hierarchy of a virtual, computer simulated human figure to control the motion of the virtual human in the computer simulation. In the first part of the paper we review several new techniques developed to facilitate the manipulation, noise reduction, storage and reuse of captured data, which have a potential to reduce the overall cost of motion simulation and improve its realism. In the second part of the paper we consider the real life problem of reducing a worker?s risk from being hit by underground mining machinery in a confined space. We formulate a set of requirements to motion editing for this particular task and analyze the limitation of existing techniques

Jan 1, 2000

By W. H. Blackburn

This paper describing the milling practice at the Tybo concentrator is one of a series of similar papers being prepared by the United States Bureau of Mines on milling methods and costs at the various mills in the United States. ACKNOWLEDGMENT A large part of this paper way prepared by H. M. Lewers, mill superintendent of the Tybo plant of the Treadwell Yukon Co., Ltd.

Jan 1, 1931

By Jeffery L. Kohler, Harvinder Singh, Jon G. Bredeson

A survey of electromagnetic noise reports was performed and a summary of the results are given. Industrial concerns were surveyed for techniques to minimize the effects of electromagnetic noise and are presented. The common types of communication links used in mines today are presented. A mathematical development was presented which determines the probability of bit errors versus distance for various types of communication links designed for in mine use. The probability of undetected errors for the protocols of the communication links is given together with burst error detection.

Jan 2, 1981

By William C. Cooley

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Jan 1, 1975

By G. H. Martindill

Complex chemical and physical changes occurring during carbonization result in a heterogeneous system composed of gaseous, liquid, and solid phases, whose relative proportions and chemical compositions change constantly as temperature increases. Studies in which the participating variables are isolated and controlled should be useful in formulating the mechanism of coal carbonization. The most characteristic property of a coking coal is its ability to form a plastic mass at a certain stage of the carbonization process. During this period it is believed that fluidity of the coal influences the properties of the resultant coke. This report gives results of an investigation by the Federal Bureau of Mines of the influence of the maximum fluidity attained by the charge on the physical quality of the coke or char produced. As a first approach to the problem, researchers investigated high-melting-point pitches, which are relatively simple carbonaceous materials. The plastic properties of these pitches, prepared specially for this work, varied greatly; their fluidities, as measured by the Gieseler plastometer, covered most of the fluidity range characteristic of coking coals. Blending these pitches with increasing pro-portions of fine coke progressively reduced their fluidities. Coal-pitch and coal-coke blends also were treated; their fluidities were varied by changing their blending ratios. The various blends were carbonized in a small-scale carbonizer and the resistance of the carbonized residue (char) to abrasion was determined in a small-scale tumbler test, using the Roga drum.

Jan 1, 1960

By Wallace W. Roepke

The Bureau of Mines studied the cutting characteristics of point-attack bits to reduce airborne respirable dust and energy during cutting. Linear cutting of two coal types using four bit types at three depths of cut with three space-depth ratios was performed with a modified horizontal milling machine using an optical particle-size monitor for respirable dust sampling. The cutting action of one bit on a rotary hardhead mining machine was mathematically analyzed and compared with the results of the linear cutting test. Airborne respirable dust per unit mass cut (specific dust) was found to be a monotonically increasing function of specific energy. Specific dust and energy decrease with increasing depth of cut. The amount of nonairborne respirable dust was 100 to 1,000 times greater than the airborne dust. The plumb-bob bit produced the most airborne respirable dust and the highest specific energy of the four bits tested. Rotary cutting was a greater dust producer and energy consumer than linear cutting because of the constantly changing depth of cut, space-depth ratio, and attack angle of the bit relative to the horizontal bedding planes. A new cutting technique is proposed to minimize the existing problems of the rotary cutting machines by providing greater production, reduced dust, and minimized methane ignition potential at the face.

Jan 1, 1976

By L. C. IlsLey

The United States Bureau of Mines has been conducting investigations of electrical equipment curing a period of more than 25 years in an endeavor to encourage the development of safer electrical equipment for coal mines. In order to conduct these investigations in an orderly manner they are carried out under a published schedule of tests known as Schedule 20, which specifies detailed requirements for motors, controllers, etc., and fees covering the various inspections and tests made as part of a routine investigation.

Jan 1, 1937

By L. C. IlsLey

The United States Bureau of clines has been conducting Investigations of electrical equipment during a period of more than 25 years in an endeavor to encourage the development of safer electrical equipment for coal mines. In order to conduct these investigations in an orderly manner they are carried out under a published schedule of tests known as Schedule 2C, which specifies detailed requirements for motors, controllers, etc., and fees covering the various inspections and tests made as part of a routine investigation.

Jan 1, 1937

By E. D. Gardner

This paper is a progress report on the study of mining methods and costs in the western United States and summarizes that part of the work pertaining to the undercut block-caving method of mining. Ore is mined on a large scale exclusively by the undercut block-caving method at the following six mines in the western United States: The Morenci branch of the Phelps Dodge Corporation, Morenci, Ariz.; the Ray mines of the Nevada Consolidated Copper Co. at Ray, Ariz.; the Inspiration Consolidated Copper Co. at Inspiration, Ariz.; the Miamo Copper Co. at Miami, Ariz.; the Ruth mine of the Nevada Consolidated Copper Co. at Ruth, Nev.; and the Consolidated Coppermines Corporation at Kimberly, Nev. The undercut block-caving method is also used at the mine of the Andes Copper Mining Co. at Potrerillos, Chile.

Jan 1, 1930

By J. E. Hamak

This publication contains analyses and related source data for 920 natural gas samples from 26 States and 2 foreign countries. All samples were obtained and analyzed as part of U.S. Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by mass spectrometer and chromatograph.

Jan 1, 1991

By C. E. Dobbin

The coal fields of Montana are widely distributed through the plains region in the eastern and northern parts of the State, and the mountain regions in the central, southern, and southwestern parts of the State. (See fig. 1.) SURFACE FEATURES The Fort Union region in eastern Montana is a broad plain of almost horizontal rocks, characterized by extensive "bad lands" along the larger streams and by red hills, benches, ridges, and buttes which represent shale and sandstone that have been fused by the burning of an underlying coal bed.

Jan 1, 1932

By S. C. Termes

To help develop the basis for new fine-particle separation methods, the Bureau of Mines has investigated the use of cross-linked starches containing four chelating groups--carboxylate, iminodiacetate, dietha-nolamine, and xanthate--as flocculants for selected metal oxide and hydroxide mineral fines. It was found that those starches capable of interacting with the mineral surface by a chemisorpti,on mechanism (as indicated by zeta potential measurements) produced the highest recover-ies and'grades of the metal oxide or hydroxide when flocculated from a binary mixture with quartz. The effects of pH, dispersing agent, stirring rate, stirring time, and starch dosage on selective flocculation were studied for binary mixtures of hematite and chromite with quartz. Floc strength becomes important in achieving maximum recoveries by mechanical postflocculation separations.

Jan 1, 1985

By A. C. Rice

This report describes a chemical process for preparing solutions of trivalent rare-earth chlorides from sulfate solutions obtained by treating bastnasite concentrate. The chief impurity in the final solution is cerium, and this element is less than 1 percent of the rare-earth oxides. The solution is used directly in the separation of rare-earth elements by ion-exchange methods. The attractive features of the process are that the chemicals are inexpensive and the steps few. The process starts with precipitating the rare-earth hydroxides from sulfate solutions with caustic soda. After the hydroxides are dried to oxidize the cerium, they are treated with dilute hydrochloric acid to dissolve away the trivalent rare-earth elements, leaving the tetravalent cerium. Details for controlling the leaching step are described. The process shortens older procedures by omitting the usual oxalate or double-sulfate-precipitation step.

Jan 1, 1959

By Rolland L. Blake

The Bureau of Mines is concerned with extracting minerals from residual geothermal brines after their heat content and some demineralized water have been recovered. This literature study is based on a survey of the literature and discussions with individuals knowledgeable on various aspects of the subject. This report examines the potential of the domestic geothermal mineral resources, considers the technical problems involved, and outlines possible effects on the environment from reservoir fluid withdrawal and reinjection. Geothermal resources in the Western United States were extensively explored during the 1960's. Limited development operations included exploratory drilling and operating wells producing hot brine, separating steam for experimental electric power generation, and recovering minerals in solar evaporation ponds or in extraction plants. Interest in the recovery of minerals and salts from geothermal fluids waned because of corrosion and scaling problems and low or no market value of the mineral products. Most of these problems can be controlled with existing technology and careful planning of processes and equipment. Extracting geothermal minerals is technically feasible, but the problems of low or no market value for major mineral products, and insufficient amounts of more valuably major products, make mineral recovery uneconomical at present.

Jan 1, 1974

By Edmund Shaw

This paper is one of a series being prepared by the United states Bureau of Mines describing mining and milling methods and costs at industrial mineral plants throughout the United states. These papers are designed to disseminate technical information regarding the methods and equipment used. The cost tabulations represent operating expenditures only and not total production costs. It is recognized that publication of total production costs might, in many instances, cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention' of the reader? is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. P. J. Weisel, Inc., with office at La Habra and plant at Corona, Calif., is the only local company that produces sand for the Los Angeles glass factories, although silica sand for other purposes is produced in other parts of southern California and the adjacent portions of Nevada. The deposit at Corona consists of coarse sand imbedded in a whitish clay and differs greatly from the other deposits, which are fine-grained sandstone that must be crushed before it can be screened and washed. The preparation of Corona sand has to be thorough and includes grinding in tube mills, repeated washing and rinsing, removal of dust by air separation, and magnetic separation of iron and other minerals. This requires a plant with a complicated flow sheet. The first plant built did not make a. satisfactory glass sand, and many additions and changes were necessary. It is thought that the present flow sheet will remain substantially unchanged until a new plant is built. The design of a new plant would be simpler, but the process would be the same.

Jan 1, 1937

By O. C. Blade

This report on the properties of aviation gasolines and aviation jet fuels produced in the United States during 1953 was made under a co-operative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. Analytical data are presented for 101 samples of aviation gasoline which include, for the second time in this series of reports, data on some samples of grade 108/135 aviation fuel. Data also are given for 32 samples of aviation jet fuel. The analyses were made on samples typical of the manufacturers' production in their laboratories and the results sub-mitted to the Bureau of Mines for compilation. The products of 19 manufacturers of aviation gasolines and of 19 producers of aviation jet fuels are represented.

Jan 1, 1954

By C. M. McKinney

The Bureau of Mines analyzed 626 crude oils from 546 oilfields in the United States that produced 2,500 BOPD or more during at least 1 of the last 3 years. Included also are crude oil analyses from eight fields that produced less but which were located in areas having few or no fields that produced 2,500 BOPD. The tables show the geographical and geological source, general characteristics. and determined and computed analytical data for each sample. The analyses were made according to the Bureau of Mines routine method and are directly comparable to other previously published analyses.

Jan 1, 1966

By J. D. Davis

The carbonizing properties of No. 2-bed coal from the Bartoy mine and No. 5- or Miller-bed coal from the Wilkeson-Miller mine, both at Wilkeson, Pierce County, Wash., were determined by the Bureau of Mines-American Gas Association (BM-AGA) method. Tests were made in the 13-inch retort at 500°, 600°, and 700° C. and in the 18¬inch retort at 800°, 900°, and 1,000° C. Fischer low-temperature and United States Steel Corporation high-temperature assays were made and the results compared with those of the BM-AGA tests at corresponding temperatures. Agglutinating and plastic properties were determined, and chemical and petrographic analyses were made. The No. 2 bed is 58.5 to 88.0 inches thick at three points sampled in the Bartoy mine. The coal is 98 percent bright and contains only a trace of fusain. A composite of three mine samples contained 13.8 percent ash. The washed sample, which was used in the tests described herein, contained 11.4 percent ash, 2.2 percent moisture, and 0.6 percent sulfur upon the as-carbonized basis and 68.4 percent fixed carbon upon the dry, mineral-matter-free basis. The heating value was 15,183 B. t.u. per pound upon the moist, mineral-matter-free basis. No. 2 therefore ranks as a high-volatile A coal and is very high in that, rank. The ash softens at 2,910° F. Except for its ash content, which is higher than the limit of 9.0 percent specified by the American Society for Testing Materials, No. 2 coal fulfills the requirements of a coking coal. It also is classed as extremely friable, the friability being 88.0 percent. The agglutinating index (7.6 for the 15 : 1 ratio of silicon carbide to coal) is high, and the plasticity as indicated by the Gieseler test (60 divisions per minute) is low for a high-volatile A coal.

Jan 1, 1942

By Jack Mantel

The goal of this 42-month contract was to increase safety in low-seam underground coal mines through development and in-mine evaluation of a temporary roof support system for roof drills and floor-riding operator compartments for a loader and shuttle car. The program was performed in three phases. During Phase I, state-of-the-art canopy technology was investigated, and preliminary design and mock-up evaluations were performed for temporary roof supports for single-and dual-boom bolters and for transverse-mounted floor-riding canopies for a shuttle car and coal loading machine. The shuttle car and loader canopies were approved for further development, and the design, fabrication, testing, and certification were completed in Phase II. In Phase III, the Bureau of Mines furnished an FMC 6L shuttle car fur use in the evaluation of the canopy for 45 shifts. The shuttle car canopy was evaluated at Virginia Crews Coal Company in West Virginia. Efforts to secure an evaluation site for the loader canopy were unsuccessful. The loader canopy was shipped to Bruceton for possible future evaluation.

Jan 1, 1985

By E. C. Baker

Costs of disposing of steel slag are estimated based on the present method and a proposed alternate method for a steel mill in the Pittsburgh area. Estimated cost data were calculated by the Bureau of Mines and do not reflect the investment and operating costs and credits of a specific steel mill and processing plant. The alternate method of steel slag disposal would result in an appreciable cost savings to the mill and concurrently supply the industrial and commercial markets with low-cost, high-quality construction materials.

Jan 1, 1970