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By Maria I. De Rosa

Table 10 and figure 4 show the number of fires and fire injuries occurring at the surface of underground metal/nonmetal and stone mines by state during 1990-2001. Table 10 also shows the injury risk rates, employees' working hours, and lost workdays. A total of 12 fires occurred in 11 states; 5 of the fires caused 5 injuries. The yearly average was one fire and 0.42 injury. Five fires with two injuries occurred at metal mines, five fires with two injuries occurred at nonmetal mines, and two fires with one injury occurred at stone mines. None of the fires involved contractors. The Ewhr value was 58 x 106 hr (Irr = 0.017), and the LWD value was 75. Nevada had the most fires (two fires and no injuries). Ohio, New Mexico, Missouri, South Dakota, and Idaho each had one fire with one injury. Of these states, Missouri had the highest injury risk rate value (In = 0.25). Table 11, partly illustrated in figure 5, shows the number of fires, fire injuries, risk rates, employees' working hours, and lost workdays by time period. The number of fires decreased during most of the six time periods. The number of fire injuries and employees' working hours decreased during all of the periods. The Irr values follow patterns similar to those shown by the injury values. Tables 12-17 show the number of fires by ignition source, method of detection and suppression, equipment involved, location, and burning material by time period. Figure 6 shows the major variables related to fires for 1990-2001. Table 18 shows the number of fire injuries per number of fires causing injuries and total fires by year, ignition source, equipment involved, and location.

Jan 1, 2004

By John W. Adams

The present status of the National Bureau of Standards program is that many magnetic tapes of analog data have been recorded in four major mines. Each mine uses different types of equipment. In addition, some surface measurements of noise have been made at two additional mines. Two types of recordings have been made: (1) broadband measurements for spectral plots and (2) narrowband measurements for amplitude probability density (APD) plots. Only data from one mine (Robena #4) has been processed and was, presented at this workshop. The short-term goals are: (1) finish processing data from the other mines, (2) establish or reduce measurement system uncertainties, (3) put Robella report into final form for distribution, and (4) hold a review to determine what has been done, to distribute and to interpret the preliminary data, and to determine what still needs to be done. Long-term goals are: (1) complete final reports on each of the mine trips, (2) establish techniques for predicting noise in mines already visited and establish uncertainty bounds for these predictions, and (3) establish techniques for predicting noise in mines that have not been visited (but that use similar equipment to those visited) and also establish uncertainty bounds for these predictions. Specific factors or formats to be presented include: (A) For underground broadband measurements: 1. 300 Hz to 100 kHz spectral plots 2. 300 Hz to 384 kHz spectral plots 3. 300 Hz to 192 kHz spectral plots 4. 300 Hz to 6kHz (subject to change to 3 or 12 kHz) spectral plots (B) For surface broadband measurements: 1. 300 Hz to 6 kHz (or 12 kHz) spectral plots 2. 300 Hz to 3 kHz spectral plots (C) For underground narrowband measurements : 1. APD plots at 12 frequencies from 10 kHz to 32 mHz of magnetic field strength 2. R. M.S. and average values will be calculated based on time averaging for these plots (D) Sample spectral measurements of: 1. Roof-bolt voltages 2. Trolley wire-to-rail voltages 3. Phone line currents

Jan 1, 1973

Determine the site specific flow behavior of leachants and groundwater during development, production, and restoration phases of an in situ leaching operation. Approach A computer program has been developed which simulates the hydrologic activity associated with in situ mining. Various user options enable modeling of many of the site specific geologic conditions and well field specifications that affect the hydrology of solution mining. How It Works In situ hydrology is modeled, using a closed-form solution to the three-dimensional, partial differential equation that describes changes in hydraulic head as a result of pumping from leachant Injection and recovery wells. Model capabilities include arbitrary well patterns and pumping schedules, partially penetrating well screens, directionally anisotropic permeability and natural groundwater flow, in either

Jan 1, 1981

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

1. Introduction This document represents Part II of our final report on the development of a "Remote Sealing System for Extinguishing Coal Mine Fires. " It is a technical report which summarizes the results of system development and field demonstration. Part I of this two - part final report is an Operator's Manual for the application of the Remote Sealing System to a coal mine fire. 1.1 Background When coal mine fires go out of control and can no longer be fought directly, the standard fire fighting technique is to construct air-tight seals in the mine passages leading to the fire area so'--,that the oxygen supply to the fire is". cut off. Ultimately, it is desirable to isolate the fire zone in such a way that normal operations can resume in the remainder of the mine. The construction of seals in the- mine causes the atmosphere to pass through a toxic and explosive phase. Explosions, if they occur, are not only hazardous to the men working at the sealing operation, but can also undo much of the sealing work which has already been accomplished. Sealing of passageways surrounding the fire zone from within the mine is extremely difficult and dangerous. Methods for direct sealing are detailed in "Control of Mine Fires'. 1 An alternative to this approach is the technique of remote sealing. This involves drilling boreholes which intersect the mine passages at the locations where the desired seals are to be constructed. The seals are then constructed by pouring material down the borehole and filling a segment of the passage from bottom to top. During this operation, there are no personnel in the mine, all operations taking place on the ground surface.

Jan 1, 1973

Reliably measure stress chan¬ges in order to assess stability of mine openings. Approach: A durable, permissible, sensor and readout system have been developed and tested. How It Works: The stress sensing element is a taut steel wire which is, vibrated at its natural frequency, If the tension on the wire is changed because of deformation of the sensor housing, the natural frequency of the wire changes. This effect is similar to decreasing or increasing the pitch of a violin string by loosening or tightening it. Because the stress sensor electrical output is a frequency signal, rather than an amplitude signal, its accuracy is unaffected by the resistance of the signal wire, or other attenuation. Signal wires can be a mile or longer without affecting accuracy. When a button is pushed on the readout box, the sensor wire is electromagnetically excited and vibrates at its natural frequency. That signal causes a readout in illuminated digits. (By referring to calibration chart and the previous reading, the user knows the change in stress.) This system is permissible. To install the sensor, a slightly oversize hole is drilled into the mine pillar. Next, a special tool is used to both position the sensor and wedge it in place. Figure 1, shows the sensor and its integral wedge and hole-fitting piece.

Jan 1, 1976

By Maria I. De Rosa

Table 10 and figure 4 show the number of fires and fire injuries occurring at the surface of underground coal mines by state during 199&1999. Table 10 also shows by state the risk rate, employees' working hours, and lost workdays. A total of 65 fires occurred in 10 states. Thirteen of those fires caused 12 injuries and 1 fatality (the yearly average was 6.5 fires and 1.2 injuries). Four fues and one fire injury involved con- tractors. The Ewhr value was 97 x l O6 hr (Irr = 0.025); the LWD value was 6,206. Pennsylvania had the most fues (20 fues and 5 injuries), followed by West Virginia (1 6 fires and 1 fatality) and Kentucky (1 5 fires and 3 injuries). Among these states, Pennsylvania had the highest injury risk rate value (Irr - 0.095). Table 1 1, partly illustrated in figure 5, shows by time period the number of fires, fire injuries, and fire fatalities; risk rates; employees' working hours; and lost workdays. The number of fires and fire injuries show a decrease followed by an increase during the five time periods, accompanied by a decline in employees' working hours throughout the periods (see table 11 and figure 5). The Irr values follow patterns similar to those shown by the injury values. Tables 12- 17 show the number of fires by ignition source, method of detection and suppression, equipment involved, location, and burning material by time period. Figure 6 shows the major variables during 199&1999. Table 18 shows the number of fire injuries per number of fires causing injuries and total fires by year, ignition source, equipment involved, and location.

Jan 1, 2004

By Lynn L. Rethi, Barbara Fotta

Recent employment figures (taken from the Mine Safety and Health Administration's database) indicate that the number of independent contractor' employees working in the coal mining industry has doubled over the past ten years. As their numbers increase, they become a more visible segment of the industry. [ ] Increased exposure to mining hazards has also brought an increase in the number of fatalities involving independent contractor workers. One gauge that is traditionally used to evaluate the overall safety of an entity is the "number of fatalities." Over the five-year period from 1985-89, 27 independent contractor employees were fatally injured while working on coal mine property. This number increased to 45 fatalities during the subsequent five-year period from 1990-94. Nearly half of these fatalities (47%) were due to accidents involving powered haulage (See Table); 13% were electrical accidents; and 9% were machinery accidents. Combined, these three accident classifications accounted for 69% of all coal nine independent contractor fatalities. Information taken from fatality data is an important piece of the safety puzzle; however, other variables need to he examined in order to better define contributing factors associated with accidents. More specifically, information on trends in fatal and nonfatal accident and injury data is necessary before deciding what approach should be used to improve safety. In order to implement appropriate safety strategies, it is important for safety practitioners to examine all available lost time accident and injury information. The following coal industry data sites specific and present trends of independent contractor employees working in underground locations at coal mines, surface areas of underground coal mines, surface coal mines, and preparation plants. The data compares employment and accidents for time periods at the beginning and the end of a ten-year span from 1985 to 1994. Because the number of incidents involving independent contractors in certain accident categories during any one year may be small, three-year totals are used; the first three years (1985-87) of the ten-year period are compared with the last three years (1992-94). [ ]

By A. M. Dale, J. Standeven, B. Evanoff

Tool manufacturers continue to incorporate new designs to the internal mechanism of tools in order to decrease the vibration that is delivered to the hand during operation. Modification of some tools to minimize tool vibration is not easily resolved through internal tool design. For this reason, vibration damping materials applied between the tool and the hand are a simple alternative. The damping materials may be applied to the area of the tool directly contacted by the operator or in a glove containing a vibration absorbing pad. These interventions are developed specifically to damp vibration but are not necessarily produced and tested under the same work conditions that a company may expose their workers. Therefore, it is important to test the value of the proposed interventions for the specific applications. This study evaluates the effectiveness of anti-vibration interventions currently in use at a local manufacturing company. Methods The design of this study evaluates the vibration energy produced at the tool handle and from the back of the operator’s hand. Each operator performed a series of fastener installations in metal using several interventions and one series with no intervention as a control. Four of the interventions were gloves containing anti-vibration material and the fifth intervention was an anti-vibration material wrapped around the tool handle. The protocol for wrapping the tool handle was developed and is part of the equipment procedure at this manufacturing company. Test conditions mimicked production work conditions including similar materials, fasteners and technique for installation. Vibration values were collected using 3 tri-axial accelerometers with one firmly glued to the tool handle close the hand grip as recommended by ISO 5349. A second accelerometer was placed on the top of the pistol shaped tool. The third accelerometer was attached to the back of the hand close to the third knuckle using double sided tape. Results Preliminary results for 3 volunteers show a difference between the vibration values of the control condition (mean hand vibration on bare hand = 1.77 Gs) compared to all of the interventions (p=.0001 using Mixed Procedure, Tests of Fixed Effects). The graph below shows individual trials for each subject for each condition. Glove 3 with the air bladder insert shows large variability between subjects (Range = 0.84-3.33 Gs). The other interventions show much less variability both within subjects and between subjects indicating consistent response with use of the intervention.

Jan 6, 2006

By Rudolf Kudlich

"The realization that fuel costs, high as compared with those enjoyed prior to the war, are apparently permanent, has caused steam power plant operators to apply their best efforts towards improving the fuel economy of their plants.Though they have given much attention to the reduction in combustion losses by improving methods of firing and improved equipment, and to diminishing the heat losses by more care in maintaining clean heating surfaces and tight and adequate baffling, they have almost universally neglected the waste that occurs from discarding unconsumed combustible with the boiler refuse.This loss varies between extremely wide limits, depending on the quality of the coal, the type of plant and the firing practice in general, the higher the ash content of the coal the greater will be the amount of combustible appearing in the refuse, and the losses will be greater as the boilers are driven at higher ratings. The refuse from stoker fired boilers is apt to have a lower aver-eve percentage of combustible than that from hand fired boilers if operated at the same rating, but stoker fired boilers are usually pushed to higher ratings and the combustible in the refuse will run higher.In actual operating practice the amount of unconsumed combustible in the boiler refuse may range from a few percent to as high as forty or fifty percent. In an informal statement one well known combustion engineer estimates that the average amount of combustible in the refuse from a large stoker fired central station boiler plant is about 15 or 20%. Assuming that the coal burned contains 12% of ash, and allowing for flue dust losses, approximately two percent of the coal will be lost through this channel. The operating engineer of one large modern central power plant reports that when burning coal of about the same ash content, the average amount of combustible in the refuse was in the neighborhood of 33%, en tailing a loss of approximately 4% of the heating value of the fuel fired. Where the coal used daily runs up into hundreds of tons, an appreciable economy could be effected by recovering this percentage."

Sep 1, 1924

This chapter details the perspective from which collected data have been examined. The first part, intended primarily for lay readers, discusses several topics related to mining as an enterprise. Initially, the organizational functioning of atypical large mine will be described. It is the formal structure above a miner that decides the conditions of his or her work. A second point of concern is the technology itself An underground coal mine is a sociotechnical system, with workers and machines organized in particular ways during production. Third, general conditions and dangers underground will be described in detail. The physical environment of an operation is a powerful factor in the work life of miners. Fourth, a discussion of the process of formal training is given. During this training, a new worker is taught what the organization expects of him or her in the role of safe, productive, coal miner. Next, there are outside organizations that act as significant forces in the workplace. Examples include the Mine Safety and Health Administration (MSHA), State agencies, and the United Mine Workers of America (UMWA). The roles of these entities will also be examined. The second part of this chapter will depict each study site as a concrete setting, so that findings can be interpreted in their proper context. The Organizational and Technical Nature of Mining A coal mine is a complex system. It is defined as all parts of a mining plant's property (both underground and surface) that contribute, under one management, to the extraction or handling of coal [American Geological Institute 1997]. As suggested, many functions that must be carried out at an operation are only indirectly related to coal mining and processing. Even the jobs that are di¬rectly related tend to be numerous and varied [Wallwork 1981]. According to Palowitch [1982], the chief reason for this sophistication is that "after more than two centuries of exploiting our coal resources, today's coal industry finds itself saddled with a horrendous legacy of human impairments and environmental damages which society demands be corrected." Now, the effects of government regulation are evident in every aspect of the mining industry. Any operation, if it is to survive, must be administered with an eye for social efficiency and accountability. Long-range planning is needed to ensure that the mine produces coal in a cost-effective manner. One of the first things that must be considered is location and method of access. To extract coal from an underground mine, a coalbed (or "seam") must be reached from the surface. The term "portal" is generally given to any entrance that provides access to a coal mine. In hilly terrain, such as is found in Appalachia, the coal may "outcrop" on a hillside. This allows direct

Jan 1, 2000

This chapter focuses on smoke as it relates to escape from underground mine fires. Among the topics discussed are the measurement of visibility in smoke; smoke-related hazards such as the production of CO, hydrochloric acid (HCI), or other byproducts of combustion; and miners' personal experiences while escaping through smoke. Smoke Measurement and Visibility In general, smoke consists of hundreds of thousands of very small particles. These particles have some "size," usually expressed in terms of their diameters, and they have some concentrations, usually expressed either in the number of these particles per unit volume or the total mass of the particles per unit volume. Humans cannot see individual smoke particles because they are too small. Similarly, "umber concentrations" and "mass concentrations" of smoke particles do not have much meaning to people unless they are trained technically. Still, individuals know that they can see smoke, independent of all the technical jargon used to describe it. Also, they know that when the smoke level gets too high, it is no longer visible. In fact, nothing is visible because the smoke absorbs all of the light in its surroundings. The eye is only sensitive to light in the wavelength region from about 400 nm to about 700 nm. The maximum sensitivity of the human eye is to light that has a wavelength of about 555 nm. It is important to know how the eye responds to light because if its response is known, it is possible to use a light detector that has almost the same response as the eye. Such a detector can then be used to quantify the visible characteristics of smoke because it responds in the same manner as the human eye. Smoke is visible because it either scatters or attenuates (diminishes) light. In some instances, smoke is visible because the smoke particles reflect light which is then detected by the eye. The eye actually "sees" an intensity of light that has been reflected from a cloud of smoke particles. Imagine shining a flashlight into a cloud of smoke. Someone off to the side can actually "see" the beam of light as it traverses the smoke cloud. This is called scattering. Smoke is also visible be¬cause it attenuates light. Imagine having someone shine a flashlight into your eyes. As smoke begins to build up along the beam of the flashlight, the light begins to dim. The smoke is visible because it is now reducing the intensity of light that falls upon the eye. As the smoke level increases, it is said to obscure our visibility. When the beam is no longer visible, the smoke obscuration is said to be 100%. In other words, none of the light energy from the flashlight makes its way through the cloud of smoke. Another way of saying that the obscuration is 100% is to say that the transmission of light through the cloud is zero.

Jan 1, 2000

By John J. Gordon, Neil K. Cooperrider

The International Organization for Standardization (ISO) standard ISO 2631 [1,2] provides three methods for evaluation of human exposure to vibrations that contain occasional shocks or impacts. Part 1 of the standard specifies the running r.m.s. or maximum transient vibration method (MTVV) and the fourth power vibration dose value (VDV). Part 5 of the standard provides a method of computing the stress in the lumbar spine for humans exposed to multiple shocks. Alem et al [3] have reported application of these methods to data for tactical ground vehicles. This paper reports and compares VDV and spinal stress evaluations of more than 90 hours of vibration and shock measurements on North American locomotives engaged in through freight operations. The measurements evaluated in this paper were obtained for full crew shifts on 19 freight locomotive runs on mainline track in locations from New York to California. The shifts ranged in duration from 187 minutes to 497 minutes. The average speeds for the shifts were from 21.0 mph to 54.6 mph. All measurements were made on locomotives hauling freight trains in regular revenue service. Data Acquisition and Processing The results reported here were computed using test data acquired from a tri-axial seat pad, accelerometer at a sample rate of 400Hz with an anti-aliasing filter corner frequency of 100Hz. The VDVs and the lateral and longitudinal spinal stress values were computed directly from the acquired test data according to the procedures specified and described in [1] and [2]. The vertical spinal stress values were computed by converting the as-acquired test data to a sample rate of 160Hz for input to the vertical spine model, as required in [2]. The conversion of the test data from the as-acquired sample rate of 400Hz to the required sample rate of 160Hz involved up sampling or interpolating the test data to an equivalent sample rate of 800Hz, band limiting the resultant data with a low-pass filter corner frequency of 60Hz and finally down sampling or decimating the 800Hz data to a sample frequency of 160Hz. Discussion The vertical VDVs computed according to [2] for the 19 shifts ranged from 2.68 to 9.33 m/s1.75. In all but one case, the vertical values were greater than the values for the lateral or longitudinal directions. Note that the health guidance in [1] puts the lower boundary of the health guidance caution zone at a VDV value of 8.5 and the upper boundary at 17 m/s1.75. The daily equivalent static compression dose computed following [2] ranged from 0.123 to 0.434 MPa. Health guidance provided in [2] states that there is a low probability of an adverse health effect if the daily dose is less than 0.5 MPa.

Jan 6, 2006

GLOSSARY Acid- and toxic-forming materials. Rock or coal layers containing significant amounts of pyrite or other minerals which, if exposed by coal mining, will cause acid or toxic drainage to occur when acted upon by air and water. Add mine drainage. Any water with a pH less s than 6.0 draining from a coal mine. Water is often orange-colored because of the presence of oxidized iron. Adit. An underground mine entry at sites where coal seams are exposed at ground level. Apple core. A complete hilltop (360°) left exposed by not backfilling the highwall. Approximate original contour. The surface configuration achieved by backfilling and grading the mined area so that be reclaimed land closely resembles the general pre-mining surface configuration and blends into and complements the drainage pattern of the surrounding terrain. Area mining. A surface mining method that is carried on in level to gently rolling topography on relatively large tracts of land. Active area mine pits may be several miles long. Arid and semiarid regions. Lands, generally west t of We 100% meridian, where water use by native vegetation equals or exceeds that supplied by natural precipitation, and rainfall is insufficient to support agriculture. Annual precipitation is normally 20 inches or less. Auger mining. A mining technique often used by surface mine operators when the overburden becomes too for the coal to be mined economically using traditional surface mining methods. Large-diameter (usually 2'-4') horizontal holes are drilled as much as 300 feet into We vertical Me of the coal bed by an auger. Like a bit used for boring holes in wood, coal augers consist of a cutting head with a screw-like extension. As the auger turns, the head breaks up the coal and the screw carries it back into a conveyor that loads it directly into a truck. Backfilling. The operation of refilling an excavation using material removed during the mining process. Bench. The level or flat working area at the base of the highwall that is excavated between the exposed coal seam and the original surface of the ground. Bucket wheel excavator. A continuous-digging machine that uses a rotating vertical wheel with buckets for large-scale stripping and excavating. Cessation Order. Order to cease mining issued to a coal operator by the regulatory authority due to severity of violations, Contemporaneous reclamation. Restoration of mined land that occurs as soon as practical after coal removal. Contour mining. A mining method commonly used in eastern mountainous topography where coal is removed in a narrow strip around the hillside. The extent of the cut into the hillside is determined by the depth of overburden at the highwall compared with the thickness of the coal seam. Daylighting. A term used to describe a surface mining procedure that exposes abandoned underground coal mine workings to enable removal of the remaining coal. Daylighting is followed by land reclamation. Dragline. An excavating machine, usually used in large, flat areas, that drags a bucket (which holds up to 220 cubic yards of material) toward the machine by cables, loads it with spoil, and then hoists it wit a boom up to 350 feet long, allowing the machine to excavate wide benches by depositing the spoil hundreds of feet away from the highwall. Grading. The process of smoothing the disturbed areas of the mine site, after the coal is removed, to closely approximate the pre¬mining terrain. Haul road. Any road constructed, improved, maintained, or used by mine operators and located within the permit area. Head-of-hollow fill. See "valley rill." Highwall. The cliff-like excavated face of exposed overburden and coal in a surface mine. Hydroseeding. Planting of seed mixed in a water medium. Water, mulch, lime, fertilizer, and seed are blended and sprayed onto regarded soil.

Jan 1, 1992

The Mine Safety and Health Administration (MSHA) defines an independent contractor as "any person, partnership, corporation, subsidiary of a corporation, firm, association or other organization that contracts to perform services or construction at a mine." Contractors that perform specific types of work are required to report the number of employees who perform work at coal mines and at noncoal mines.

Feb 1, 2005

To reduce operator exposure to drilling noise from roof bolting machines. Background Noise-induced hearing loss (NIHL) is a prevalent occupational illness in the United States. Studies indicate that 70%?90% of miners have NIHL significant enough to be classified as a hearing disability. Mine Safety and Health Administration studies indicated that roof bolting machine operators are among those overexposed to noise. Field studies support the premise that, on average, drilling is the loudest noise source to which a roof bolting machine operator is typically exposed and contributes greatly to the operator?s noise exposure. The National Institute for Occupational Safety and Health (NIOSH) has further determined that the drill steel and chuck radiate a significant amount of noise during drilling. To address this noise hazard, NIOSH developed a collapsible drill steel enclosure (CDSE) to encapsulate the drill steel during the drilling portion of the roof bolting machine duty cycle. In addition, NIOSH is collaborating with J. H. Fletcher & Co. in the continued development of a CDSE.

Sep 1, 2008

By Susan B. Bealko

Mining provides a large part of the energy and raw materials that feed this Nation's economy. Copper pipe, concrete, and window glass serve as well known examples of the reliance on minerals in modern society. Less appreciated, but as important, are the hundreds of mined commodities that are an integral and necessary part of everyday products, ranging from medicines and computers to carpet and paper. Coal is a major portion of the country's energy mix today, as it will likely continue to be in a future hydrogen-based economy. The domestic mining industry also provides strategic minerals that are important for the Nation's security. The processes to recover these mineral commodities are among the most demanding and complex in an industrial society, and this inherently dangerous industry has historically had the highest risks of fatality and injury. The mining industry has been undergoing some trying and challenging times because of the recent mine disasters in the coal fields. These events have been alarming in light of the strong and encouraging safety record that has characterized mining in the United States for most of the past decade. While mining communities deal with their grief, mine operators, government regulators, and other safety personnel, set about trying to determine why these fatalities occurred. Subsequently, the mining industry is currently experiencing changes in legislation at an unusually rapid pace. The most recent regulatory changes are the Mine Improvement and New Emergency Response Act of 2006 (MINER Act) and the temporary emergency standard for mine seals. The new mine safety laws call on the nation's mines to adopt certain procedures and safety technologies immediately, or as soon as they become commercially available. Putting all the provisions in place from these new laws is a major undertaking, and will necessitate strong collaborations and partnerships among mine operators, manufacturers, regulatory and research agencies, labor unions, and community groups. It is against this background that Prevention through Design (PtD) components for the Mining Sector are recommended.

Jan 1, 2008

By F. J. Gallagher

The purpose of this circular is to present information on the construction and use of reinforced rubber-jacketed tubing and insulating air-line couplings in coal mines where Airdox is used for breaking coal in order to eliminate, insofar as possible, arcing at the face between Airdox tubing and the track or other face equipment.

Sep 1, 1949

By R. V. Ramani, K. V. K. Prasad, M. Swaminathan

"Engineering design involves, in addition to numerical calculations, considerable amount of expertise and judgement. The expertise and judgement is required to conceptualize and idealize the problem, select a suitable mathematical model for the problem and to interpret the model results in terms of stipulated design constraints. In recent years, knowledge based systems (KBS) have provided the capability to integrate the qualitative experiential and expert knowledge with ~he quantitative knowledge for improved analysis and design of systems. A possible KBS architecture for mine ventilation system design was discussed by Ramani and Prasad · (1987). The expert system (ES) component of the KBS supports the analysis and interpretation phases of the ventilation design process with an algorithmic program used for the solution of alternate designs. The purpose of this paper is to discuss the data and knowledge needs for developing such a system and a formal means of their representation on the computer. A number of ES shells were evaluated to explore possible development and delivery environments for the system. A brief summary of this evaluation is also provided.INTRODUCTIONLuxbacher and Ramani (1979) have discussed the design process of mine ventilation systems and have provided the interrelationships that exist between ventilation, strata control, drainage and material handling systems and mining methods. They have also outlined the importance of correct analysis of the problem, choice of the right solution method and a rigorous interpretation of the solutions. The expertise required for analysis and interpretation phases was identified as the key element in developing effective and efficient ventilation system designs. Such expertise is embedded in the right choice of questions to be asked of the user as well as in directing the user to a wide array of alternative methods that may satisfy the design requirements. With advances in artificial intelligence applications in recent years, particularly expert systems, the integration of expertise into traditional mine planning and design algorithms has been facilitated. These planning and design aids, employing the integration of numeric and symbolic logic and called coupled systems, are powerful tools for engineers to tap the benefits of experts (Kitzmiller and Kowalik, 1985; Fenves, 1985). The purpose of this paper is to discuss the means of representing knowledge for the design of mine ventilation systems through the use of a coupled system. The KBS is visualized as consisting of the following components:"

Jan 1, 1989