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By Isaac A. Zlochower, Michael J. Sapko, Ronald S. Conti

The Bureau of Mines has developed a system using a high-speed electropneumatic mechanism for the rapid (grab) sampling of dusts and gases during an explosion. The sampling system consists of an aluminum housing that incorporates two 30-cm3 preevacuated glass vials with rubber septums. Upon actuation, the sampling probe needle is driven through the septum with a pressurized air pulse, filling the tube with gas and dust from the mine explosion. After a predetermined time, the sampling probe needle is retracted by a second high-pressure air pulse to its normal (quiescent) state, allowing the sampling tube to reseal. The onset and the duration of sampling are independently variable and controlled by a time-delay relay package. This technique enables the monitoring of pyrolysis-charring in coal particles and the generation and combustion of the pyrolysis vapors in both large- and small- scale explosions. The following results were obtained from full-scale dust explosion tests at the Bureau of Mines Lake Lynn Laboratory: (1) Gas sampling of the leading edge of the flame front shows the large concentration changes, characteristic of the flame front; (2) gas samples taken entirely in the flame zone consist of pyrolysis and combustion products with very low residual oxygen; and (3) the particles collected in the flame zone show signs of extensive pyrolysis and charring.

Jan 1, 1988

By Rodrigo Werneck Athouguia

O cerne desse trabalho consiste em demonstrar os resultados obtidos pela implementação de um programa de Lubrificação Confiável na Samarco Ubú com objetivo de reduzir custos através da busca contínua pela lubrificação classe mundial. A Samarco Ubú entende que uma lubrificação de qualidade contribui diretamente para os equipamentos, aumentando a vida útil. A gerência de manutenção lançou no final de 2013 um programa de Lubrificação Confiável com objetivo de buscar continuamente as melhores práticas de lubrificação no mundo.Esse programa abrange desde o recebimento do lubrificante até a manutenção do mesmo no equipamento em condições ótimas de trabalho, capacitação da equipe e as melhores práticas de lubrificação.

Aug 16, 2017

By T. W. Guy

The increased moisture due to water-spraying for coal dust control is of interest even for mines from which the coal is to be wet-washed before screening, because in many cases wet coal dust materially de- 20-mesh X 0 sizes as pct ROM average ............................... 6.3 pct Range 2.3 to 9.5 pct 20-mesh X 0 sizes as pct 3/8 X 0 sizes average........'...................... 18.9 pct Range 12.7. to 23.9 pct creases the loading efficiency of men and equipment at the faces. It also causes a serious increase in the normal wear and deterioration of all equipment with which it comes in contact. It is important to the consumer if it increases his as-received moisture. No attempt will be made in this paper to cover the entire subject of water-spraying of coal for dust control. It will be confined to discussion and data on (I) percentages of dust in bituminous coals, (2) moisture increases due to spraying for dust control in mines or plants by methods which have proved satisfactory for periods of one to five or more years, and (3) a few suggestions for research. Size and Percentage or Coal Dust The U. S. Bureau of Mines1 classifies as coal dust all bituminous coal passing a 20-mesh sieve (0.0328 in. square opening). The percentage of such dust to be found in ROM coal, of course, varies widely with the characteristics of the seam, and with the methods used in the mining and in the preparation of the coal. ROM screen analyses of 12 U. S. coals selected at random from personal files given in Table I show: A few other screen analyses examined indicating 40 pct or more of 20-mesh X 0 dust in 3/8 in. X 0 sizes were not included because of uncertainty that they were representative. The number of results in Table I is not sufficient to give a reliable estimate of the average, or of the range to be expected, but it indicates that in every case the coal dust is a relatively large percentage of the total ROM coal, and, of course, a progressively larger percentage of resultants as the larger sizes are separated for marketing.

Jan 1, 1949

By D. J. Hawthorn

The widespread interest shown during the past year in the study of subsurface pressures warrants brief reference to its early development. Though it is impossible to set an exact date when constructive thinking on the subject first began, nevertheless, evidence is available that thought was given to the problem as far back as 16 or 1.7 years ago. There is record in one of the foreign journals of actual subsurface tests made by crude methods in one of the Rumanian fields in 1918 and 1919.' These tests were performed in conjunction with studies made on wells produced by bailing and, incidentally, the final outcome of the work led to the development of the so-called "duplex bailer" which is reputed to have trebled volumetric bailing efficiency. From this time on to 1927 a few scattered bottom-hole pressure determinations were made with makeshift instruments of one form or another, but probably not until 1927 was any great amount of concerted effort directed to the subject. At this fall meeting of the Petroleum Division four years ago was presented one of the first papers2 to appear in this country written for the express intent of advocating the value and importance of subsurface pressure determinations. It is thought to have been the first to present direct data on subsurface pressures obtained through the use of a specially designed recording instrument. As might be expected, the instrument had its limitations, but reasonably accurate results were obtained and, to say the least, it constituted a progressive step in the right direction. During the period from 1927 to 1931, many noteworthy improvements were made in the design and perfection of subsurface pressure instruments suitable to meet all conditions. Because of the magnitude of this task much credit is due the men who pioneered this work. They should feel a keen sense of satisfaction in the thought that their efforts have paved the way for the continuation of this most valuable study. At the present time more than a dozen companies are operating subsurface pressure instruments in the Mid-Continent field. Engineers in

Jan 1, 1933

By Frances Jane Cromwell, D. J. McAdam, G. W. Geil

INTRODUCTION IN a series of papers, the authors and their associates have shown that the technical cohesion limit is affected by the same four factors that affect the flow stress, namely, the stress system, plastic deformation, temperature, and the strain rate.16-28 Moreover, each of these factors affects the technical cohesion limit in the same way that it affects the flow stress.‡ The influence of any one of these factors may be represented by a curve of cohesion limits, although only one point on the curve may represent actual fracture. As the term "fracture stress" has come into use with the same significance as "technical cohesion limit," the authors are here using the shorter term with the understanding that it does not always refer to actual fracture. This paper presents the results of an investigation of the flow of notched and unnotched specimens between yield and fracture. A study has thus been made of the flow and fracture of metals as affected by the stress system, and of the ductility of metals as affected by the stress system throughout plastic deformation. Since two of the principal stresses were equal (S2 = S3), the stress systems can be represented in terms of the radial stress ratio, the ratio of the transverse radial stress S3 to the longitudinal stress Sl.* The results of the experiments are represented by a series of complete flow-stress curves for each of the metals investigated, and these diagrams have been used for the development of other diagrams of various types. Ludwik was the first to suggest that fracture occurs when the flow stress becomes equal to a technical cohesion limit. Although Ludwik was incorrect in his view that the technical cohesion limit depends only on the amount of plastic deformation and not on the stress system, he was correct in his view that the flow-stress curve for any stress system terminates at a point representing a technical cohesion limit. The authors have seen some recent references to assertions by other investigators that a point representing the fracture stress need not be on the flow-stress curve. The Ludwik principle, however, would seem to be axiomatic, provided that the flow stress and fracture stress are properly defined and that the fracture stress is properly determined. Disregard of this principle has led to some untenable theories of criteria for fracture. When a metal is very ductile, the conventional method of determining the ductility and fracture stress by dividing the breaking load by the sectional area after fracture, generally gives values that are much too high. With some metals and in some conditions, the fracture stress thus determined may be two or more times the

Jan 1, 1948

By D. G. Hartley, P. C. Hayward, K. R. Weller, U. J. Sterns

The major copper loss at Mount Lyell is in the coarsest particles presented to flotation. An analysis of data collected from the five Primary and six secondary ball mill circuits showed that grinding was limited by low breakage rates in secondary mills, possibly due to oversize balk. For five months, the make-up ball size for one secondary mill was reduced from 50 to 30 mm (2 to 1.1 in.). Frequent steady-state tests indicated that overall average breakage rates could be increased by about 70% using smaller balk. A mathematical simulation of the whole circuit with increased breakage rates showed that the resultant finer grind was likely to improve copper recoveries by about 2%.

Jan 1, 1984

By Kenneth Cottingham

The number of completions in 1944 in Ohio was only slightly greater than completions in the preceding year, but the initial daily volumes both of oil wells and gas wells declined considerably. The dry-hole ratio was a little lower than in 1943, even though in the year under review considerable effort was made to find new production. No new areas of consequence were discovered. Thirteen new gas pools, the largest of which was 1000 acres and the average 565 acres, were opened during the year. Eleven of these pools were in the Clinton sand, one was in the Oriskany, and one was in the Berea. Approximately 15 small pools might also be rated as discoveries, but because only one or two wells have thus far been completed in each, they cannot at present be properly evaluated. The latter pools average about 120 acres each. Some extensions were made to existing gas pools. The number of oil wells drilled was only one less than in 1943, yet compared with the year 1941, when twice as many oil wells were drilled, the difference is startling. Effective Aug. I, 1944, a blanket subsidy was granted of 35¢ per barrel on all Cleveland-Chatham, Coming, and Lima grades of oil, and 75¢ per barrel on Pennsylvania grade crude. The subsidy was authorized by the Office of Price Administration, with reimbursement to purchasers of the various grades made through the Defense Supplies Corporation, a branch of Reconstruction Finance Corporation. For several years the small operator, particularly the owner of stripper wells, was in a serious position. The subsidy has been a means of real help and, in addition to aiding the operator, it has prolonged the life of many small wells that otherwise would have been abandoned, with consequent loss of daily production and unre-covered reserves. It is questionable whether the price increase is sufficient to revive production of Corning grade, which has

Jan 1, 1945

By M. B. Bever, A. B. Michael

THE structure of cast A1-Si alloys is altered profoundly by modifying agents. Sodium, in particular, reduces the size of the silicon particles in the eutectic and tends to change their shapes from plates to nearly rounded grains. This refinement is accompanied by a shift of the eutectic to higher silicon concentrations and lower temperatures. Similar effects can be attained by rapid solidification. Hypotheses advanced to explain modification have involved the formation of a ternary eutectic,1 the removal of oxides by fluxing,' and even a presumed allotropic transformation of silicon. Other hypotheses assume that the modifying agent causes an envelopment of the silicon particles by the aluminum-rich solid solution, but attribute this envelopment to different mechanisms. According to various explanations, the growth of the silicon particles is obstructed by an immiscible sodium-rich liquid," an adsorbed layer of sodium,' or a ternary compound;5 his obstruction has been conceived as purely mechanical or as a colloidal action.' It has also been proposed that sodium reduces the surface tension on the Al-Si interface, thus permitting the aluminum-rich solid to grow faster and to envelop the silicon particles.? Still other hypotheses stress undercooling and the attendant change in the rate of nucleation of silicon, but fail to ascribe any definite function to the sodium addition." '" Procedure High-purity alloys of aluminum and 3 or 7 pct Si were treated with modifying agents containing radioactive sodium tracers. The experiments were intended to investigate the partition of sodium between the primary aluminum-rich solution and the eutectic, and, if possible, to determine whether sodium is concentrated in or around the silicon particles in the eutectic. Radioactive sodium fluoride, alone or mixed with stable sodium chloride, was allowed to react with the alloy for 5 min immediately before solidification in the crucible. Modification could not be attained with additions of less than the equivalent of approximately 0.1 pct Na. Some alloys were not completely modified, but comparison of the structures of treated and untreated specimens indicated a very considerable reduction in particle size of the silicon in all of the former. A treated alloy is shown in Fig. 1. Radioactive sodium fluoride was prepared by bombardment with deuterons having an energy of 14 mev. This bombardment (totaling, for example, 6 microampere-hours in one run) produced radioactive Na24 (half-life 14.8 hr) by the reaction 11Na23 (d,p) 11Na24. The radioisotopes of fluorine also produced have short half-lives and were not detected. A half-life determination by counting confirmed that the measured activity was due to Na24. The distribution of the sodium in the solidified alloys was determined by an autoradiographic technique by which a suitable stripping film is attached to a very thin metallographic specimen. After exposure and development, this emulsion remains superimposed on the specimen and may be examined microscopically or photographed by reflected light. The emulsion of the autoradiograph can be correlated directly with the underlying surface by simple adjustment in focus. The details of this technique have been described elsewhere." Results Fig. 2 is a micrograph of the autoradiographic emulsion ("autoradiograph") lying directly above the area of eutectic in Fig. 1. Fig. 3 shows a similar autoradiograph of a region consisting of primary solid solution. The small black dots (tracks) in these autoradiographs are developed grains in the emul-

Jan 1, 1954

By J Vann

Mineral Resource and Ore Reserve estimation is a challenging and demanding field, requiring application of professional knowledge, skill and experience of the highest order. If the many potential pitfalls are to be avoided, however, there are two other requirements which are of equal, if not greater, importance:good communication, and common sense. Estimation of Mineral Resources and particularly of Ore Reserves is almost always a team effort, involving a number of disciplines. Good teamwork requires good communication, both between team members and between the team and other parties having an interest in the process. Breakdown in these lines of communication can have far reaching effects on the project under consideration. The need to use common sense during a Resource or Reserve estimation exercise would seem to be self-evident. It is surprising, however, how often rigid adherence to procedures and methods prevails at the expense of clear thinking, usually with adverse and sometimes fatal effects on the project under consideration. This has become increasingly true as computerised methods have assumed a central role in Resource/Reserve estimation. The critical question that estimators should ask themselves at all stages of the process is: æIs what is being done sensible given the data available, what is known of this deposit and the purpose of the exercise?Æ

Jan 1, 1999

Australian contract mining as it is known today had its origins in the early-1980s. Before this time there were numerous examples of underground mine development, and specifically shaft sinking being carried out by contractors. However, these were typically international contracting companies who came to Australia for specific projects. Growth in the underground mining industry in the 1980s opened up the opportunity for contractors. Mine owners had a need for contractors who could bring technical and operational capabilities to a project combined with capital in the form of equipment. In the early years the contracting industry was dominated by smaller players who focussed on mine development. The relationship between mine owner and contractor was loose and typically contract documents were rarely referred to. Through the 1980s and 1990s the underground contracting industry in Australia grew to where today there are over 20 underground contracting companies operating in an industry with an estimated annual value in excess of $1 billion. Of these 20 companies approximately five dominate with annual turnovers exceeding $100 million. Underground contractors now provide all facets of underground mining including development and production. Over the last 20 years the underground contracting industry has been able to consistently lower costs to mine owners through a combination of:equipment productivity, labour productivity, and technical innovation.

Jan 1, 2002

By F. M. L. Mulaudzi

Metal dusting is a corrosion phenomenon that occurs in strongly carburizing gas atmospheres at elevated temperatures. Reaction kinetics and product characterizations of Alloys 602CA and 800 were examined by scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) and X-ray diffraction (XRD).The results showed that Alloy 602CA is more resistant to metal dusting than Alloy 800. Visual examination and SEM surface analysis showed that Alloy 800 suffered metal dusting attack after a relatively short exposure period. The amount of coke deposits increased on Alloy 800 with increased exposure from 96 to 336 hours. X-ray diffraction on the reacted surfaces identified graphite and austenite in both alloys and some iron oxides/spinel for Alloy 800.

Jan 1, 2012

By J. S. Miller

THIS paper describes the method of mining a steeply pitching anthracite seam on a heavy pitch in the Orchard vein in No. 1 Tunnel of the Lehigh Coal and Navigation Co. The Orchard vein in the Nesquehoning district has a thickness of about 15 ft. on the level of the gangway, which is sufficient thickness for the gangway to be driven full width in coal. Above the gangway, the vein becomes thinner and near the surface is about 8 ft. thick. The coal is of good hard quality and carries a fairly good roof. The pitch of the vein is between 65° and 70°. Usually the breast-and-pillar method has been employed in the mining of the steeply pitching veins in this section. This method produced good results as far as the mining of the breast was concerned but the recovery of the pillar was difficult as to full extraction and expensive as regards costs. To recover these pillars after the breasts were driven, three methods were commonly employed; they were known as the pillar-breast method, pillar-skipping method, and pillar-chute method. The pillar-breast method consisted in putting a battery in one corner of the pillar (Fig. 1), coupling the manways A and B of the two adjacent breasts for two or three lengths ahead of the working face of the pillar being cut, and working the pillar as a breast. This method was used by the more skilled miners of the earlier days but has practically been abandoned. A slight variation of this method is used to some extent. In this case, the pillars are left wider than ordinarily and of sufficient width for the full-width breast to be driven in and a small pillar left on each side of the pillar breast between it and the regular breasts. With the completion of the "pillar breast," the ribs are drilled full of holes, loaded, and fired.

Jan 3, 1925

By C E. J de Ronde, J L. Mauk

Sulfide chimney samples collected during the 1998 - 1999 R/V Atlantis û DSV Alvin 3 - 30 research cruise have been examined and classified into four types, based on common characteristics. Chimney morphology is the most important characteristic and resulted in the following groups: 1. flutes, 2. cones, 3. wide-flats, and 4. beehives. Other characteristics resulted in the classification of subgroups within the flute, cone and wide-flat groups. The combination of characteristics, including; the presence of an orifice, internal chimney fabrics, wall thickness, extent of weathering, and the presence of Alvinella worm casts, enable evolutionary trends between the different chimneys types to be established. These trends indicate that with time, flutes evolve from immature zoned chimneys with a central orifice and smooth thin-walls, into cone chimneys with thick walls and massive fabrics which have their orifices infilled by massive sulfides, and a rough exterior. Repeated mineralisation within, cones may result in the formation of wide-flat chimneys. Beehive chimneys can form at any time during chimney growth.

Jan 1, 2003

Lieutenant Gorman was born in Ottawa, Canada, in 1888, and after preliminary education at Ottawa University and the Ottawa Collegiate Institute, he graduated from McGill University in 1913, as a mining engineer. After graduation, Mr. Gorman spent several months in a tour of Europe. The year 1909 was occupied at one of the Canadian graphite mines, and the summer of 1911 he spent with the Granby Mining, Smelting & Power Co., Ltd. At the time of his admission to the Institute, in 1914, he was sampler with the Dome mines at South Porcupine, Ontario. His next engagement was at the Creighton mine, Ontario, but in 1916 he joined the Canadian Expeditionary Force and went to England. A letter written by Major Ritchie, commanding the Second Tunnelling Company, to Lieut. Gorman's mother, contains the following words. Tommy was lulled at our headquarters by a nine-inch shell which struck the officers' quarters. The Hun had been shelling a small village close to the camp with a long-range gun and a shot fell into our camp. Tom was killed instantly by the concussion. He mas buried this morning with Military Honours in the military cemetery close to our camp. Tommy was an efficient officer and a good soldier and his loss is very keenly felt by the officers and men of this unit. Lieutenant William Hague William Hague, First Lieutenant Co. F, 116th Regiment of Engineers, and a member of the Institute since 1906, died of pneumonia in France, on Jan. 1, 1918. Lieutenant Hague was born in Orange, N. J., Mar. 31, 1882, the son of the late James D. Hague, a distinguished mining engineer and a life member of the Institute, and Mary Ward (Foote) Hague, of Guilford, Conn. He attended Milton Academy, Milton, Mass., and was graduated from Harvard in the class of 1904. He was a nephew of the late Arnold Hague, of the United States Geological Survey. Seven years ago he married Elizabeth Stone, of Milton, who with their son, James D. Hague, six years old, survives him. Lieutenant Hague's mining career began immediately after his graduation from Harvard, when he went to Bisbee, Ariz., to be a surveyor's helper in the mines of the Copper Queen Consolidated Mining Co. In 1905, he became an instrument man, being engaged on the construction work of the Copper Queen smelting plant at Douglas, Ariz. In the latter part of the same year he was transferred to the geological depart-

Jan 1, 1920

By Raja P. Upadhyay

An evaluation of the economics of mining the deep, thick oil shale deposits of the central portion of the Piceance Creek basin, Colorado, U.S.A. is presented in this paper. For the analysis, a modified large scale underground mining system developed by Cameron Engineers, Inc. and the Gas Combustion retorting process developed by the U.S. Bureau of Mines were used to determine capital investment and annual operating costs. A modified risk analysis computer program was then used to calculate DCFROI’s for various grades of oil shale and selling prices of partially refined shale oil. Sensitivity analyses were performed to quantify the affect of bonus bid payments, operating costs, capital investment, and all costs on DCFROI. In addition, a probabilistic evaluation was made to determine the risk involved in obtaining desired rates of return. Results of the economic evaluation indicate that for current selling prices of crude oil a high risk is involved in obtaining a DCFROI of 15%, unless only higher grades of oil shale are mined. However, mining only the higher grade oil shales, 125 l/mt (30 gpt) and above, would effectively reduce the potentially mineable resources by 90%. Risk can also be reduced through higher selling prices of shale oil. Sensitivity analyses indicate that the capital investment has a three times greater effect on required selling price than total operating costs.

Jan 1, 1977

By V. Barúa

El presente estudio revisa el panorama historiográfico sobre las etapas del minado de tajo abierto desde el pasado, presente hasta el futuro. En el pasado, la minera superficial a tajo abierto surgió para obtener principalmente materiales no metálicos de construcción, alcanzando su auge a partir de las últimas décadas del siglo pasado. Sin embargo, existieron algunos obstáculos en el desarrollo de su mecanización y tecnología que posteriormente fueron mejoradas. Posteriormente, existe una competencia por desarrollar equipos mecánicos de mayor capacidad y operación, como un interés por el advenimiento de nuevas tecnologías y uso de la investigación. Finalmente, el panorama sobre el futuro del minado a cielo abierto, presenta condiciones en las que no se asume nuevos progresos mecánicos ni mayores espectativas que en el pasado.

Nov 20, 1972

By Russell F. Palmer

"THE PRACTISING MINING ENGINEER has little time for the expression of opinion on abstract questions concerning the definition and future of mining engineering. The following comments indicate some of the thoughts and suggestions of those who have found mining engineering a very satisfying field of endeavour. The future of mining engineering has been under discussion for perhaps twenty years. It is significant that the University of Saskatchewan program was in- 88 traduced at the time that some traditional mining schools were questioning the need for mining engineers. One Canadian university, and some American schools, actually abandoned the field at this time, some ten years ago.Five years ago, Mining Magazine sponsored an international debate on training for the future, and concurrently, the CIM undertook a major survey of the mineral industry's manpower needs. The current CIM discussions should prove more fruitful, as they are directed toward mining engineering alone, rather than the broad, and confusing, spectrum of all professionals and semi-professionals of the mineral industry."

Jan 1, 1972

By R. C. Bunge

Many minerals float best with fatty acids in the intermediate pH range. For example, fluorite, a semi soluble salt mineral, exhibits a maximum contact angle and a maximum flotation recovery in the pH range of 6-8 after conditioning in a palmitate solution (fig. 1). The maximum in flotation coincides roughly, as many researchers have observed, with the boundary of bulk precipitation of the fatty acid. According to fig. Z this boundary is in the above case of 5xl0-7 M palmitate approximately at pH 6.3. For assessing the phenomena occurring at the bulk precipitation boundary of fatty acids, the surface tensions of carboxylate solutions have been measured under various conditions. Fig. 3 shows the surface tension development of palmitate and myristate solutions of increasing concentration at pH 12. Also shown are the bulk precipitation edges (BPE) of the respective solid species that is stable under these conditions, that is the potassium acid soap, HKAZ. Both curves display a similar behavior. As the concentration of carboxylat,e increases, the surface tension decreases, until a minimum is reached at which the curves level off. The decrease of surface tension with increasing carboxylate concentration is generally taken to indicate the surface excess of the carboxylate ion. The point where the curve suddenly levels off has not yet been explained. While it is well known that the onset of micellization (CMC) may cause such an inflexion of the surface tension curve, this cannot be the case here because the position of this point depends, as shown in fig. 4 for palmitate, on pH (the CMC is generally independent of pH). We believe that this point indicates the precipitation of a colloidal acid soap (colloidal precipitation edge, CPE) before the bulk precipitation of this species sets in (BPE).

Jan 1, 1994

By R. Fraher

Hazard analysis utilizes interaction mechanisms in combination with geologic, structural and mining conditions to delineate areas of potential damage in seams subject to interaction. Using characterizations of conditions peculiar to multi-seam mining, such as innerburden thickness, geology and structures, initial interaction contour maps can be constructed. Geologic hazard analysis is then carried out on roof, pillar and floor conditions in the affected seam using lower seam rock properties and layout geometries in the overlying seam. Either safety factors or damage ratings can then be developed representing degree of hazard in the lower seam. The final hazard map shows both the aerial extent and magnitude of potential damage from interaction.

Jan 1, 1992

By C. L. Schaidle

Computers and communications technology have revolutionized many industries. In earthmoving, this revolution has just begun. The major changes are still to come but are just around the corner. This article presents a vision of this upcoming revolution in the earthmoving industry. This vision includes basic communication, machine monitoring and diagnostics, job and business management, planning and operations, and machine control. For the industry to realize maximum benefits from the information age, it must have a vision of the future that is shared by technologists, machinery producers and miners. History of the information age During the 1970s, the information age revolutionized retailing, starting with the grocery business. By using bar codes and laser scanners, individual items were connected to the information world of computers and communications. Once this connection was made, the data on what an item was and where and when it moved became valuable information for inventory control and marketing. Not only was the information valuable, it was easy and inexpensive to collect and manipulate. The effort required to provide the consumer with the right product at the right time was reduced. Costs went down and customer satisfaction went up. But there were casualties of this revolution. Many inventory counters lost their jobs. There were also equipment casualties. Cash registers that could not interface with the digital world were discarded long before the end of their useful life.

Jan 1, 1994