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By W. G. Davenport

Chapter 6 examined autotherrnal smelting of pure chalcopyrite concentrate with 50 mass% O2-50 mass% N2 blast. It showed that production of 1500 K products with this blast requires: 181 kg of pure oxygen 337 kg of air per tonne, of concentrate. It also showed that the grade of matte produced with this blast is 58% Cu. This chapter re-examines autotherrnal smelting by asking: (A) WHAT COMPOSITION BLAST (MASS% 02 -MASS% N2), 298 K, WILL AUTOTHERMALL Y PRODUCE 65% Cu MATTE 1500 K FROM PURE CHALCOPYRITE CONCENTRATE? (B) HOW MUCH PURE OXYGEN AND AIR WILL BE NEEDED? These are important questions for flash? smelting because furnace operators usually want to send specific composition matte to converting. This chapter shows how a specified matte can be produced autotherrnally with 298 K oxygen-air blast. Later chapters show how it can be done with hot blast, hydrocarbon combustion, different concentrates etc.

Jan 1, 2001

By G. F. Sowers

Excavation bracing is a special structural system. It is built from the top down. The design is controlled by the economical construction of another structure as well as by the movement of the ground beyond the limits of its construction. It serves a number of purposes, all subordinate to the construction of the principal structure. Despite its importance, bracing design and construction is frequently overlooked in project planning, causing delays and expensive changes. Thoughtful planning, good design and resourceful, innovative construction can improve construction safety and save time and money.

Jan 1, 2010

By L Torckler, R L. Brathwaite

At Neavesville gold-silver (electrum) mineralisation occurs in steeply-dipping zones of intense fracturing, brecciation and quartz veining within rhyolitic pyroclastics, carbohaceous shales and andesites. Hydrothermal alteration extends over an area of greater than 3 by 1.5 km. In rhyolitic tuffs, highly silicified zones containing quartz-adularia-illite assemblages are flanked by less silicified assemblages composed of albite, illite-montmorillonite and chlorite. The mineralogy and sequence of alteration are comparable with the alteration zones which envelop the steam-producing fissures of the active Wairakei and Broadlands geothermal fields. Primary fluid inclusions in quartz from five fissure veins in the Neavesville field show maximum homogenisation temperatures ranging from 220 - 260¦C and salinities of 0.0 - 1.1 wt per cent NaCl equivalent, which cover a similar range to actual measured temperatures and salinities in geothermal fluids at Wairakei and Broadlands. The age of the rhyolitic pyroclastics and related alteration and mineralisation is probably Pliocene and Neavesville therefore represents a fossil geothermal system. The intensely fractured zones containing the gold-silver mineralisation were probably produced by hydraulic fracturing generated by accumulation under pressure of hydrothermal fluid in blind fault zones. Study of fluid inclusions indicates that hydrothermal quartz associated with electrum was deposited under boiling conditions. High grade electrum mineralisation at Graces workings appears to be localised by reaction of hydrothermal fluid with sedimentary marcasite in black shale.

Jan 1, 1980

By E. Gybbon Spilsbury

(Pittsburg meeting, March, 1910.) THE recovery of gold and silver from their ores by means of the cyanide process has been so successful in the last few years that any radical improvement would seem impossible; yet the appliance to which I wish to call attention in this paper is really a radical departure from the methods now in general use. The most modern and approved of these, known as the all-sliming method, depends for its success on the grinding of the. ore so fine that practically 90 per cent. of it will pass through a 200-mesh screen. The slimes thus produced are then agitated and aerated in tanks of various types. The main object of this treatment is to insure such a thorough admixture of the pulp and solution that every particle of the ore is surrounded by a volume of solution sufficient to insure the dissolving of the whole of the gold- and silver-content. In addition, in order to expedite the action of the cyanide, and to oxidize such elements as would, if left in their active state, become cyanicides, air is blown in under pressure. In the Pachuca tank, this air is the active and sole means of agitation. The chief objections to all the methods off agitation used heretofore are the expense of operating and maintaining the mechanical devices for keeping the pulp in suspension, and the length of time required to obtain a fairly complete extraction. of the values. These objections are inherent to any method of agitation effecting a circulation of the pulp and the solution together, by giving the whole mass a circular movement, as in the low-tank system, or a vertical circulation, as in the Pachuca-tank system. In both methods, the particles of ore are kept traveling in the same direction as the solution, and with very little difference of speed; so that, while the whole mass is in

May 1, 1910

By G. Adachi, K. Machida, T. Ozaki, K. Murase

The chlorination rate with CCl4 was unexpectedly slower than carbochlorination using chlorine under the same reaction conditions. Chlorination with CCl4 was topochemical and the amount of monazite reacted after different periods suggested that the kinetic control step was the reaction between CCl4 and the monazite core at the interface. The kinetic order of the reaction was 0.5. The presence of a complex former, AlCl3, promoted the chemical vapour transport of rare-earth chlorides as complexes

Jun 18, 1905

By Henry A. Stiff, J. P. Hammond, A. B. Westerman, H. C. 195-000-000-014 Cross, and Lawrence E. Davis

The phases in Cr-Fe-Mo alloys have been investigated with homo-genization, aging temperature, composition range, and alloy addition as variables. Metallography, three X-ray methods, and hardness were used as methods of study. The behavior of s, M23,C8, and Z phase are reported for cornpasition range 60 pct Cr-15 to 25 pct Fe-15 to 25 pct Mo-<0.005 to 0.36 pct C with aging at 1400º to 2000°F. With 2 pct Ti, Tic and TiC-TiC are formed; with nitrogen Cr2N. THE recently developed class of chromium-base heat-resistant alloys shows appreciably higher strength than commercially used high temperature alloys. However, further developmental work is required to impart needed shock resistance and some degree of room-temperature ductility to these alloys. Extensive exploratory work on chromium-base alloys was begun in a program initiated by the War Metallurgy Committee of the National Defense Research Council at the Climax Molybdenum Co. in the early part of 1942.&apos; Alloys were sought for gas-turbine blades for use at 1600°F. A minimum of 5 pct elongation in the stress-rupture test was a requirement. From the Climax work, ternary alloys of chromium, iron, and molybdenum appeared to show the greatest promise as materials for gas-turbine blades. The composition line in the ternary diagram joining the 60 pct Cr-15 pct Fe-25 pct Mo and 60 pct Cr-25 pct Fe-15 pct Mo alloys was indicated as representing the most useful combination of strength and ductility.&apos; Strength increased while ductility decreased as molybdenum was raised in this composition range.&apos; The 60 pct Cr-15 pct Fe-25 pct Mo type alloy was thought to have the most suitable properties for gas-turbine blades.&apos; Concurrent with the study reported here, other investigations were being made on Cr-Fe-Mo alloys. The liquidus temperatures on a series of low carbon, ternary alloys were being determined, and isothermal sections drawn at 2370°, 2010°, and 1650°F (1300°, 1100°, and 900°C).2 Also, various methods of preparation and some mechanical and physical properties of chromium-base alloys, particularly the 60 pct Cr-15 pct Fe-25 pct Mo type, were being investigated., At the inception of the present program, only a limited study had been made of etchants for developing the microstructures of chromium-base alloys; X-ray analysis of the microconstituents had not been made. A review of the literature revealed that no phase-diagram work had been reported on the Cr-Fe-Mo system. Scope of Work The work on chromium-base alloys includes the following: 1—The development of etching methods for differentiating between the microconstituents; 2—The identification of microconstituents by X-ray diffraction methods; and 3—A comprehensive metallographic and hardness study after various heat treatments. The phases were studied by three standard X-ray techniques: 1—The block-sample focusing-camera method; 2—The powder-diffraction method on elec-trolytically separated residues; and 3—The powder-diffraction method on cold-worked aggregate samples. The results by the first two methods were correlated with the metallographic data. The third method was used largely to study conditions approaching equilibrium, since cold working prior to heat treating accelerated precipitation. Seven types of alloys were investigated: 50 pct Cr-50 pct Fe, 40 pct Cr-40 pct Fe-20 pct Mo, 55 pct

Jan 1, 1953

By P. L. Sibrell

The U.S. Bureau of Mines has tested cyanide leaching for recovery of palladium (Pd) from spent petroleum processing catalysts. Three different catalyst samples were supplied by a spent-catalyst processor. These catalysts consisted of a zeolite base and contained 0.4 to 0.7 pct Pd. During alkaline cyanide leaching, the catalysts exhibited ion-exchange properties due to their zeolite matrices. Hydrogen ions were released from the zeolite in exchange for sodium ions in solution, resulting in a significant decrease in solution pH. This could present a safety hazard because of the potential for release of toxic hydrogen cyanide gas. A pretreatment step where the catalysts were contacted with a 1.0M sodium hydroxide solution was found to prevent the pH shift from occurring. Following the sodium hydroxide pretreatment, two stages of leaching at 160 °C with solution containing 1 pct sodium cyanide and 0.1[M] sodium hydroxide gave at least 75 and up to 95 pct Pd recovery. The Pd was quantitatively recovered from the leach solution by thermal decomposition in an autoclave at 250°C for 1 h. The Pd content of the precipitate was over 50 pct. Thermal decomposition also decreased the total cyanide content of the barren solution to less than 0.2 mg/L. The catalyst leach residues passed the Federal Toxicity Characteristic Leaching Procedure and the California Waste Extraction Test, indicating that landfill disposal of the leach residues would be acceptable.

Jan 1, 2010

By Stephen C. Tadolini

PC-Strand tendons, commonly referred to as cable bolts, have become a major rock reinforcement device for underground mining and civil applications. The most common configuration is a 1+6 strand, which designates a center king-wire, with six outer wires wound around it to form a 0.6-in (15-mm) diameter cable. The capacity of this tendon approaches 30 tons, but the performance is largely dependent on the anchorage medium and the ability of the system to transfer stresses back into the rock mass while reinforcing and suspending the immediate roof. Recent developments to improve the transfer mechanisms of the PCstrand via the anchorage medium by impregnating the individual wires with uniquely designed deformations have resulted in improved anchorage and subsequent cable bolt performance. This paper describes a series of laboratory tests used to develop the initial indentation patterns and numerical modeling simulations that were undertaken to refine and optimize the final designs. The new, indented PC-Strands, offered in both bright and properly galvanized, have been tested in the field and are being used effectively in two new cable bolt products. The results of the laboratory, computer modeling, field testing and in-situ installations provide a glance at the next generation of cable bolts. This suite of testing shows how they will improve the safety and serviceability of openings under adverse ground conditions.

Jan 1, 2012

By Walker G. S

A study of the crystalline materials on or near the surface of freshly made or &quot;green&quot; superphosphate granules and mature, &quot;set&quot; superphosphate granules was undertaken using X-ray diffraction, X-ray mapping, scanning electron microscopy and electron probe micro analysis techniques. Calcium sulphate (CaSO4), calcium sulphate hemihydrate (CaSO4 1/2H20), and mono calcium phosphate monohydrate (Ca(H2PO4)2H2O), were the only crystalline species present in the &quot;green&quot; superphosphate.In the set superphosphate however, additional compounds were present, namely complex iron and aluminium phosphates Ca(Fe,AI) H(HPO4hF2)2H2O, (Fe)3(H3O)H8 (PO4)6H2O and calcium sulphate dihydrate (CaSO4.2H2O).The complex phosphates tied up the major part of the Fe and Al in the system and were concentrated on or near the surface of the granule. An intimate mixture of CaSO4.2H2O, and CaSO4, along with the above mentioned complex Fe-AI compounds, crystallize close to the surface of the granule and cause the setting of superphosphate that takes place during storage.

Jan 1, 1980

By Thomas M. Larimer

Prior to April, 1961, the coal charge to Clairtonts coke oven batteries was 3" x 0" mine waslied coal having approximately 6.0% to 7.0% moisture. Even at this size and moisture content, the arching, rat-holing and hang-up was excessive and the effective live storage of coal was only 60% to 70% of the rated capacity of the coal bunkers, depending upon the moisture of the coal. In addition, many production delays were encountered in the time and methods required to fill the larry cars. The need for an improved metallurgical coke led to the introduction of pulverized coal to a portion of the plant in 196 1. When the full potential of the pulverizing equipment was realized, we were able to serve seven batteries in our second unit of batteries with pulverized coal through two coal bunkers. The discharge hoppers of these bunkers were equipped with air vibrators to assist the flow of pulverized coal into the larry cars. The vibrators were helpful in this respect but required considerable maintenance and caused damage to the bin plates.

Jan 1, 1968

By William H. Spice

Drilling activities in South Central Texas for the year 1945 continued the steady increase over the past two years, while new fields discovered for the year included four new gas fields and one field extension. In the 30 counties included in this area, which comprises district No. 1, Oil and Gas Division, Railroad Commission of Texas, 141 exploratory wells were completed, compared with 61 drilled in 1944 and 29 drilled in 1943. Of these 141 tests, 55 were field well and 86 were wildcats; 38 were completed as oil wells, S as gas and gas-distillate producers, and 95 were abandoned as dry. Atascosa and McMullen Counties were the most active in the district, accounting for 73 of the wells drilled.

Jan 1, 1946

By Wern-ping (Nick) Chen

The Florida Department of Transportation District 6 (FDOT D6) began a study in 1987 for a master plan to improve the traffic circulation and congestions between the Port of Miami (POM) and downtown Miami, FL. This study included a tunnel connection between two man-made islands, the Watson and the Dodge islands. Though a finding of no significant impact (FONSI) was completed in 1992, the project remained on hold for about 10 years. In 2002, Florida Turnpike took over this project, re-evaluated its benefits to the lo-cal communities, determined its feasibility (specifically the tunnel options) and established a probable cost. In 2005, the FDOT D6 regained its charge over the project and concluded that a bored tunnel under Biscayne Bay is feasible. Its primary components are: ? Widening of the MacArthur Causeway Bridge, to accommodate truck traffic to the Port of Miami. ? A tunnel connection between Watson Island and Dodge Island, where the POM is located. ? Connections to the POM roadway system, either for the traffic from the city of Miami or for the truck traffic from I-395 to the POM. The project will improve access to and from the POM and provide a dedicated roadway connector linking the POM with the MacArthur Causeway (State Route 41/1) and I-395, specifically for the trucks in and out of the POM without going through downtown Miami. As identified in the project information memorandum (PIM), its primary objectives are to: ? Improve access to the POM, helping to keep it competitive and ensuring its ability to handle projected growth in its cruise and cargo operations. [ ] ? Improve traffic safety in downtown Miami by removing POM traffic, trucks and buses from the congested downtown street network and, in doing so, facilitate ongoing and future development plans in and around downtown Miami.

Jan 1, 2009

By R. P. Bhagat

The paper reports results on sinterability of iron ores from the mines of Tata Steel Limited. The objective was to improve tumbler index (TI) of sinter and its reduction parameters, reduction degradation index (RDI) and reducibility (RI) while maintaining strand productivity same or to improve. Pot sintering experiments were carried out with Joda and Noamundi mines having LOI 3.8% and 2.9% respectively. Sinter basicity (CaO/SiO2) was varied in the 2.1 to 2.5 range and its MgO content was kept in the 1.4% to 1.8% range according to the blast furnace requirement. The ignition condition and vacuum was maintained according to the plant practice. The effect of variables namely, granulometric composition of ores vis-à-vis that of sinter mix, bed height, solid fuel, moisture content of green mix on the sintering indices was studied. The productivity with Noamundi ore (26 %+6.3 mm) was lower than that with Joda ore (45% +6.3 mm) at 4% coke in the mix and sinter basicity (CaO/SiO2) 2.1. However, with 4% coke (ash 22%) the RDI value was significantly high in case of Noamundi Ore, which decreased significantly to 29% with 5% coke. The size parameter of ore fines and its LOI content do influence the sintering speed and the sinter properties significantly. At 2.1 basicity ratio, the sinter with the Joda ore having coarsergranulometry had highest TI (=70.2%). The RDI (27%) in this case was inferior to that (23.2%) when Joda ores with finer size was sintered. Better RDI with finer sized ore could be attributed to better assimilation of CaO/ MgO with more balanced and uniformly distributed hematite minerals. The size parameter has been inter-influenced by the coke requirement. With the lower mean sized Joda ore the sinter RDI decreased significantly to 23% and the productivity improved to 42.9 T/(sq m*d) when the coke in the mix increased from 4% to 5%. An attempt to reduce the coke in the mix from 5% to 4% with respect to both the ores was not successful as it resulted higher RDI and lower strand productivity. The present study has revealed that sinter RDI improves (decreases) with decrease in the sintering time, while such correlation was absent between TI of sinter and speed of sintering. Corollary to this observation, one can take advantage of other stronger parameters to increase the sintering speed (and hence sinter productivity) without affecting the sinter strength. In the present study higher FeO sinters has displayed excellent RDI, however cold strength of sinter was not correlated with its FeO content. The TI and RI parameters of sinter improves marginally with increase in its MgO content while RDI got worsened. Keywords: LOI content, iron ore, reduction properties, sinter, noamundi, joda

Sep 1, 2012

By M. J. Walker

The lead .smelter at Cominco&apos;s operations at Trail, B.C. has been undergoing. a modernization program since 1986. In that year a contract agreement was reached with German-based Lurgi GmbH which allows Cominco to construct and operate a lead smelter using Lurgi&apos;s QSL process. Cominco Engineering Services Ltd. (CESL), a subsidiary of Cominco Ltd., was contracted to provide project management, engineering, procurement and construction management? services for the project. The new smelter replaces the existing sinter-blast furnace plant ?and will have a capacity of up to 1601000 tonnes per year of refined lead. This new smelting proc.ess results in significant operating cost reductions and major environmental .improvements. Start-up of the new plant is scheduled for the fall of 1989. The metallurgy and the operating parameters, important to the design of the new smelter, are described together with projected deportments of lead, zinc, silver and minor metals. A plant description, will be given for the following major areas that make up the modernization project: the pressure filter operation for the preparation of ,zinc leach residues feed material, the QSL reactor and boiler itself, together with its feed system and process gas treatment, and the drossing plant with a new continuous drossing furnace and oxygen softening and thallium removal. Slag from the QSL reactor will be treated in existing slag furnaces until a subsequent second phase of the modernization is completed in the 1990s.

Jan 1, 1990

By John Wulff, J. H. Hollomon

SERVICE failures in brass condenser tubes are often due to corrosion. One of the commonest types of corrosion reveals a surface structure of redeposited copper.1 The study of the effect of alloy addition agents in preventing this kind of corrosion has received impetus from the extensive publication of Bengough and May.2 The mechanism of such inhibition gauged from immersion corrosion,&apos; cell corrosion,&apos; and electrolytic potential&apos; measurements is controversial. This controversy may be attributed in part to a lack of definite knowledge5 of the actual nature of the initial films formed in corrosion experiments. In our own corrosion work on copper and 70-30 brass this lack became apparent and necessitated an examination of surface films by X-ray and electron diffraction methods. The present paper is but an introduction to the subject of inhibition and reports the structure of films formed in active corrodents. EXPERIMENTAL PROCEDURE The arsenical coppers and brasses used in this investigation were made by one of the writers* in the plant of the Revere Copper and Brass Co. at Rome, N. Y. Standard commercial melting practice was followed. O.F.H.C. copper and electrolytic zinc were used and all arsenic additions were made by additions of a master copper alloy. The final analyses are given in Table I. Likewise, the extrusion, cold-rolling, and intermediate anneals employed followed standard usage. Final heat-treatments were given to all materials to produce a similar grain size (0.035 to 0.045 mm. for brass and 0.015 to 0.025 for [ ] copper) for the alloys containing various percentages of arsenic. Samples ¼ by ½ by ¼ in. were cut from sheet material resurfaced and finished with 0000 metallographic papers. The surfaces were all degreased in alcohol and benzine before immersion. After immersion in the corrodent, they were washed gently in tap water, dipped first in alcohol and then in pure benzine and allowed to dry in the diffraction apparatus. The reflection electron diffraction apparatus used has been described by Burwell

Jan 1, 1941

By James M. Barker

The occurrence of borates and zeolites at Mesa del Alamo is well documented by McAnulty and Hoffer (1) and Lefond and Barker (2). Further investigation indicates the presence of priceite and meyerhofferite in addition to the howlite (1) and colemanite (2). Analcime occurs in addition to the clinoptilolite and phillipsite (2). The Mesa del Alamo area is about 200 !a south of Tucson, Arizona, and 13 km southeast of Magdalena, Sonora, Mexico, just south of the unpaved road to Cucurpe (Figure 1). The geology and mineralogy of northcentral Sonora is known only on a regional basis except for small areas mapped in detail during copper exploration. The study area is within the Basin and Range province of North America from which borates and zeolites are now produced in California. The borates and zeolites at Mesa del Alamo occur in geological environments similar to those of the Mojave and Death Valley regions of California (3, 4). Thus, a detailed exploration pro- gram in the Magdalena area could result in the discovery of economic borate and/or zeolite deposits.

Jan 1, 1979

By Edward D. Elkins

CalMat Co. is one of the largest producers of construction aggregates in the United States. The CalMat Reliance plant is located in Irwindale, California, and is situated on an alluvial fan formed by the San Gabriel River. The fan deposits are of Quaternary age and were derived from granitic and metamorphic bedrock exposed in the San Gabriel Mountains to the north. The sediments are poorly sorted and range in size from large boulders to clay size particles. The coarse material is hard and durable and consists of quartz diorite, granodiorite, granitic gneiss, schist and minor amounts of volcanic rock. The matrix is comprised of silty sand with varying amounts of clay. Thin silt and clay lenses occur sporadically throughout the deposit. The clay content of the matrix and the degree of weathering of the coarse material increases with depth. Based on seismic data, the alluvial fan varies from 200 to 400 feet thick and overlies crystalline bedrock. The Reliance plant was constructed in 1971 and 1972. It has a nominal capacity of 1200 to 1400 tons per hour, and typically produces more than three million tons of aggregate products per year. Alluvial fan sediments are mined from a gravel pit situated adjacent to the plant. The material is fed through a mobile, 48- by 60-inch, in-pit jaw crusher, then transported by conveyor to the main plant to be processed. The plant is modern and highly efficient. It has a typical wet and dry circuit and is capable of producing a wide range of aggregate products. To extend the life of the plant, a 9,000 foot conveyor system is being constructed to connect it to a granite quarry operated by Azusa Rock Inc. The quarry is located north of Irwindale, and is 50 percent owned by CalMat Co. The conveyor will be used to export crushed rock from the quarry to Reliance. The existing plant will be modified to process the crushed rock.

Jan 1, 1995

By Donald J. Ninteman

This Bureau of Mines publication is a literature study of the problem of spontaneous oxidation and combustion of sulfides in underground mines. It summarizes the present-day hazards, process mechanisms, and prevention and control techniques of this growing problem in underground mines. The iron sulfides generally have the greatest tendency to oxidize, particularly pyrrhotite. The presence of moisture and oxygen is essential for the oxidation reaction. Highly fractured sulfides, when found with timber or combustible refuse in slowly circulating air, pose the most serious fire hazard. Quenching with water is effective in quickly dealing with local hot spots, but ventilation at high flaw rates is the most effective and economical means for long-term prevention and control.

Jan 1, 1978

By J. Navoyski, B. Macdonald, W. J. Helfrich, J. L. Bellanca, B. Demich

DISCLAIMER The findings and conclusions in this paper are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention. Mention of company names or products does not constitute endorsement by NIOSH. ABSTRACT The pervasiveness of high-fidelity video games raises expectations of quality, detail, and lighting in virtual reality (VR) applications. However, high-quality models of mining equipment and environments are often not readily available, and developers may not be familiar with the latest techniques, such as physically based rendering (PBR). Because a consistent aesthetic is critical for maintaining immersion and controlling visual stimuli in research as well as in training, researchers at the National Institute for Occupational Safety and Health (NIOSH) created an asset development workflow. This paper details this workflow, including precision modeling and PBR techniques as well as a rigorous review process. It also describes lessons learned in the creation of photorealistic VR assets. BACKGROUND Virtual reality (VR) describes the simulated experience generated by an assemblage of hardware and software that are used to immerse the user. Over many years VR developers targeted the development of virtual environments (VE) toward various purposes: entertainment, the treatment of phobias [1], rehabilitation [2], and training [3]. A large part of the VE development includes digital assets, where digital assets refer to the non-programmed elements including 3D models, audio, and user interface. Because vision provides nearly 10Mbps of data [4] and accounts for the majority of all sensory input combined [5], a focused effort on asset appearance in VEs is warranted. Furthermore, research has shown that higher-resolution imagery increases search performance and training transfer, necessitating high-fidelity assets [6, 7]. In addition to being visually appealing, it is important that the assets and environment are also dimensionally accurate and consistent in order to elicit appropriate responses from the end users as they interact with and among these items [8, 9]. Researchers at the National Institute for Occupational Safety and Health (NIOSH) have developed VEs and digital assets under several research projects over the course of the last two decades [10, 11, 12, 13]. This work has provided researchers with a strong knowledge base for digital asset development. However, the assets themselves have had limited reuse value. Due to the extended timeframes and limited scope of these projects, the previously developed assets are not consistent in visual quality and dimensional accuracy. Moving forward, researchers wanted to minimize future development time and use of resources as well as adopt new asset development tools and game engine technology. Therefore, the aim of this paper is to document a new asset development workflow including geometry, materials, UV layout, and shader implementation combined with review steps in order to produce high-fidelity simulation assets that are accurate with consistent characteristics, using repeatable methodologies that are well documented.

Jan 1, 2019

By A. T. Iannacchione, D. G. Puglio

The Bureau of Mines established geologic factors affecting the mining of the Lower Kittanning coalbed to aid in coalbed minability studies and examined the occurrence of "wants" (places where coal is missing) and types of unstable roof rock strata. Trends established from mapping, including prediction of areas of high methane emissions, were extrapolated to unmined areas. "Wants" in the coalbed are of two types: Erosional and depositional. Erosional features occur where north-south-trending sand-filled channels cut into the coalbed. Variations in depositional environments have caused the coalbed to "split" into several thinner units. Slickensides, commonly indicative of unstable roof, are adjacent to and on the underside of sandstone channels; they were caused by differential compaction and by soft sediment sliding along the contact between the sandstone and adjacent shale. The frequency of unstable roof also increases where the interval between the Middle and Lower Kittanning coalbed is less than 30 feet. The zones of weakness at the contacts above and below the Middle Kittanning coalbed are the controlling factors for unstable roof in these strata. Methane emissions from the coalbed are controlled primarily by depth, fracture permeability, and rank of coal. Local geologic factors are coalbed thickness, associated rock strata, structure, and proximity to outcrop.

Jan 1, 1979