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By Herbert Clark Hoover, Lou Henry Hoover

As stated in the preface, the nomenclature to be adopted for weights and measures has presented great difficulty. Agricola uses, throughout, the Roman and the Romanized Greek scales, but in many cases he uses these terms merely as lingual equivalents for the .German quantities of his day. Moreover the classic language sometimes failed him, whereupon he coined new Latin terms adapted from the Roman scale, and thus added further confusion. We can, perhaps, make the matter dearer by an illustration of a case in weights. The Roman centumpondium, composed of zoo librae, the old German ceniner of 100 pfundt, and the English hundredweight of 1112 pounds can be called lingual equivalents. The first weighs about 494,600 Troy grains, the second 721,900, and the third 784,000. While the divisions of the centumpondium and the centner are the same, the Libra is divided into 12 unciae and the pfundt into 16 unizen, and in most places a summation of the units given proves that the author had in mind the Roman ratios. However, on p. 509 he makes the direct statement that the centumpondium weighs 146 librae, which would be about the correct weight if the centumpondium referred to was a ceniner. If we take an example such as " each centumpondium of lead contains one uncia of silver", and reduce it according to purely lingual equivalents, we should find that it runs 24.3 Troy ounces per short ton, on the basis of Roman values, and 18.25 ounces per short ton, on the basis of old German. If we were to translate these into English lingual equivalents of one ounce per hundredweight, then the value would be 17.9 ounces per short ton. [ ]

Jan 1, 1950

By Cecil E. Lester

Since the advent of coal mining, the minimal lighting in the under¬ground working place has been an obstacle to the safe and efficient performance of the miner's many tasks. Compounding this problem is the fact that the machines being operated in the working place are so large that the vertical and horizontal clearances around the machinery are severely limited. Consequently, in these poorly lighted and congested working places, the machine operator is unable to utilize his peripheral vision. He cannot see hazards as they develop and, too often, cannot react in time to avoid serious injury or death to himself or his fellow miners. The greatest hazard to miners inby the last open crosscut is from falls of roof which are often preceded by warning signs such as falling rock fragments, roof supports taking weight, or a sudden reduction in the height of the working place. These warning signs often go undectected because the machine operator's attention is focused on the small circle of light emitted from his cap lamp. Congress recognized the illumination deficiencies, and, in the Federal Coal Mine Health and Safety Act of 1969, charged the Secretary of the Interior with the authority and responsibility for development and promulgation of minimum standards for illuminating working places in coal mines. These standards have been developed and, as stated in the April 1, 1976 Notice, Federal Register, Volume 41, No. 64, will be promulgated on October 1, 1976, as mandatory regulations under Section 75.1719, Title 30, Code of Federal Regulations. The regulations require that the designated surfaces within the miner's normal field of vision be illuminated to 0.06 foot-lamberts while self¬propelled mining equipment is being operated in the working places. The term "working place" is defined in the Act as "the area of a coal mine inby the last open crosscut".

Jan 1, 1976

By R. V. Ramani, A. S. C. Owili-eger

List of Numbers

Jan 1, 1974

By C. B. Manula, R. L. Sanford, R. A. Rivell

A - Contains the coordinate pair information for deriving the co¬efficients of the 3rd degree polynomial which approximates the loading station equation. C(N) - Coefficients for third degree approximating polynomial. I - General DO LOOP variable. K - Position in BRANCH of next character. L - Format specification in DEFINE FILE statement. X - Uniform displacement for random uniform number. Y - Load increment At. AO-A3 - Coefficients of approximating polynomial for loading station equation. GR - Grade direction, or grade resistance. IQ - Counts quadruples of distance grade speed and end of route for determining total distance. IT - Intersection counter in XXXDEF. Il - Station number trip is leaving. Jl - Station number for trip destination. J2-J8 - Motor assignments and functions for given trip. KK - Location of starting grade and distance in DISTGR KK - Position of decimal point in real number. KZ - DO LOOP variable for motor assignment check. LL - Location of ending grade and distance in DISTGR. Ll - Position in IECB of station satisfied. L3 - Next available position for IECB sort. MM - Flag for printing the failure of sanding to overcome slippage. NN - Trip destination in MOTSER RR - Rolling Resistance. XK - Station level or type.

Jan 1, 1974

Engineering controls for overburden drilling include dry dust collection systems, wet dust suppression systems, and enclosed cabs [Zimmer and Lueck 1986; Volkwein et al. 1979]. Proper maintenance of the dust suppression system is critically important for drills using dry dust suppression methods. Failure to rigorously maintain these systems will result in inadequate dust control. Acute silicosis has been reported in miners operating equipment that relies on dry dust suppression [NOSH 1992].

Jan 1, 1997

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Jan 1, 1997

By R. V. Ramani, V. T. Burgos, J. A. McClay

Introduction The Cost program was developed to provide the planning engineer with a tool to evaluate the cost implications of the technical mine design decisions. Direct costing methods are employed, where feasible, to provide greater detail and accuracy in the primary cost centers. Options have been provided in the cost computation, economic analysis, and output data subsystems to increase the flexibility of the system. Computer Program The program is written in Fortran IV for use in the IBM System 360/370 computers. i. Main - The main routine reads and stores input data from three sources, user input, Cost Data Library, and data transfer from the Master Design Simulator. Data is trans¬ferred to the appropriate subroutines, as they are called, by means of labeled common blocks. ii. Subroutine CSTCOM - is a data modification routine which computes the peripheral charges related to labor and supervisory costs. iii. Subroutine MANPWR - interrogates section data to determine the total labor and supervisory costs for each cost center. iv. Subroutine CAPCST - computes the total capital investment for each cost center, including the economic life and salvage value of each element. Capital costs are determined by user selection of quantities and models of equipment. Equipment costs are stored in the Cost Data Library for retriev-

Jan 1, 1975

By Craig Haase

A. Introduction

Jan 1, 2003

By R. V. Ramani, C. B. Manula, A. Owili-Eger

PART 1 THE INPUT AND OUTPUT DATA AND THE MINE SCHEMATIC SHOWING THE FLOWS FROM COMPUTER SOLUTIONS FOR APPLICATION I

Jan 1, 1975

By Karl J. C. Harries

"The Table of Contents that follows is only an example and is the Table of Contents from an actual negotiated agreement. It is merely intended to show how an agreement might be set out and the nature of possible provisions. As a negotiated agreement the format was dictated by the negotiations. It is not offered as a precedent of what should be contained in a joint venture agreement (“JVA”), the “proper” sequence of Articles, or a complete listing of the contents of joint venture agreements generally. The set-up used for an agreement should be decided by the parties and be one they consider flows in a logical and workable sequence. This example sets out the “deal” first, followed by the provisions relating to how work is to be carried out and then by administrative provisions necessary to make the agreement work. If you are more comfortable with, say, having the Committee provisions at the beginning, by all means have it drafted that way -- you are going to have to live with the agreement and work under it.Notes:1. The Table of Contents provisions appear in bold print. The italicized sections are annotations, which have been provided in some cases where the heading may not clearly describe the contents. They are not intended to be comprehensive, but refer to some specific matters that are considered to be of interest or to need some clarification.2. The subject matter of many of the articles and paragraphs is discussed or commented upon in the text of the book. Some of section cross-references have been provided. Such references are only to sections where the topic is a principal subject and no attempt has been made to provide a comprehensive indexing.3. Although this particular agreement is a three-party agreement, *B* and *C*, the Owners, are required to act as a unit (see para. 1.09. – § 8.44.), making the agreement effectively a two-party agreement. The parties insisted upon having a decision-making Committee and structuring the agreement accordingly. As is explained in § 8.11., such an arrangement is not recommended and can result in problems.5. See also §§ 8.24., 8.41. and 14.13. for discussions on tables of contents, summaries, and headings."

Jan 1, 2003

By R. V. Ramani, R. Stefanko, G. W. Luxbacher

MINE VENTILATION NETWORK ANALYSIS

Jan 1, 1977

By Dan Nilsson

INTRODUCTION A company must have an objective, and that usually is to earn money. In some countries an objective can also be to reduce unemployment in an area or to develop nonindustrialized areas. Government-owned companies can also have as an objective that of serving the com¬munity. This discussion is limited to the consideration of normal companies wanting to earn money. Such an objective, however, has to be defined in more detail. It is not satisfactory only to maximize the total annual profit from, for example, a mining project. In comparison with most other branches, the mining in¬dustry is very capital intensive. When starting a new project, the mining company must invest a lot of money in mines, ore treatment plants, etc. It is normally many years before any income is received from the ore. Fig. 14 illustrates the payments for a new mining proj¬ect with an expected lifetime of 10 years. Whether this project is a profitable one depends on a lot of things. If the company has a shortage of money, it can be impossible to finance the project. Even if the company has enough money, the management may think that perhaps the project may not return the money fast enough. Such limitations will not be discussed here. Suppose that the company has internal funds from its own operation or can borrow them. Since the mining company must invest the money in advance, it is not satisfactory only to add all of the costs during the mine's lifetime and compare them with the total income during the lifetime. The company must include the time value of the capital. In this appendix, the basic investment theory neces¬sary to judge the profitability and costs of mining proj¬ects will be discussed. INVESTMENT THEORY Time Value of Money If a private person has a dollar and puts it into a bank, he or she will receive interest. If the interest rate is r%, the value after one year will be $(1 + r), after 2 years $(I + r)2 , etc. The interest rate represents the time value of money. If the same person wants to have $1 in the bank af¬ter one year, he or she has to put $(1 + r)-1 in the bank today. If the person wants $1 after 2 years, it is neces¬sary to put $(1 + r)-2 into the bank today, etc. So one dollar today is worth more than one dollar tomorrow. It is, of course, not correct to compare money at differ¬ent times since each dollar has a different value. It is necessary to transform all payments to the same point in time. That is called the calculation of the capital value of a cash flow, and to do this an interest rate is used. In the same way, the cash flow from a project like that shown in Fig. 14 can be translated to any other point in time. Most common is to translate all payments to the beginning of the mining period. That capital value is often called the present capital value. Interest Rate What interest rate will the company use? A com¬pany, just like an individual, has the basic alternatives of keeping its money in the bank and receiving interest, or borrowing money from a bank and paying an interest rate. The interest rate represents the time value of money for the company. If the company has a shortage of money, or many good potential investment projects, it has to use a higher interest rate than if it has a lot of money available. Most companies also increase their interest rate as a hedge against the risk involved by using money for uncertain investments, because of taxes, etc. Capital Value When the interest rate has been decided, it is possi¬ble to estimate the capital value of a project. Here the discussion will be limited to the estimation of present capital values. Suppose that one wants to know the present capital value of $1 (Fig. 15), which will be received after n years. To transform it n years back in time, one must multiply it by the factor (1 + r)-, where r is the inter¬est rate the company uses. Table 1 gives these factors for different years and interest rates. Example: At the end of year 5 a mining company has to invest $50 million in a new mine. What is the present capital value at the end of year 0? The company uses an interest rate of 15%a.

Jan 1, 1982

By G. Grassmück

The question of whether the air curtain principle could be used under conditions prevailing in Canadian metal mines was investigated. A vertical, portable BERRY air curtain was tested, at first in a wind tunnel built at Ecole Polytechnique at full scale (8-by 8-ft cross section) to simulate a drift and its lateral connections, and then in the haulage ways of a metal mine under actual conditions. The results permit us to predict under what conditions this type of air curtain is capable of acting as an air stopping or flow regulator and how it could be further developed.

Jan 1, 1969

By R. Heikkilä

As a part of a large research and development program in Finland, a system calibration for an UAV measurement method having practical experiments in a Jorvas Railway Yard design and construction project. The Railway yard construction are was measured using an UAV measurement device by Smartplanes (Smartone) and using some reference points measured by a GNSS device. The measured data was cleaned, combined and adjusted through Least Squares Optimization using the software developed by a Finnish company Pieneering Oy. As references, two different laser scans as well as total station surveys were used. For applicability evaluation, the accuracy of measurement, the reliability of measurement, and the economy of measurement were used. Based on the comparisons, the achieved precision of the UAV measurement was high, instead the accuracy of measurement was not sufficient in this case. The principle of this photogrammetric measurement includes a lot of redundant observations making it possible to achieve a high level of reliability. The economy in this Railway Yard Design project was not able to achieve.

Aug 1, 2013

By A Jewbali, R Perry, R Inglis, L Allen

"The use of conditional simulation to characterise mine plan uncertainty is increasing for the assessment of risk in mining projects. While the development of grade uncertainty profiles is relatively straightforward and can be validated using standard geostatistical techniques, the addition of geological uncertainty to evaluate total risk remains problematic. Some of the problems associated with geological uncertainty methods include the clustering of data in favourable geologic units, difficulty in training image definition and the inability to address change of support issues for categorical variables. Despite these obstacles, the importance of geological uncertainty as a contributor to total uncertainty has prompted Newmont to explore and evaluate the use of various techniques (and combinations of techniques) on different deposit types.Two orogenic deposits of different geological complexity were selected for the study: Subika, a shear zone-hosted deposit, and Merian, a deposit containing gold mineralisation associated with quartz vein zones and stockwork within which are found higher-grade quartz breccia zones. Newmont trialled various categorical simulation approaches to determine the applicability of these methods for each deposit type and the effect of parameter choice on the width of the uncertainty interval. Some of the techniques that were trialled include multiple point statistics methods, sequential indicator simulation using local probabilities as well as variations of these methodologies.The goals of this study included: gaining an understanding of which techniques may work best in which deposit types gaining an understanding of the intricacies of each method gaining an understanding of the effect that each method has on total uncertainty analysis.This paper presents a comparison of the various techniques and makes recommendations for their use in uncertainty analysis.CITATION:Jewbali, A, Perry, R, Allen, L and Inglis, R, 2014. Applicability of categorical simulation methods for assessment of mine plan risk, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 85–98 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 24, 2014

By Raymond F. Moran

The history and development of the FMC Coke process has been reported in numerous presentations over the past 10 years (1, 2, 3, 4, 5, 6) but a short review is desirable, especially regarding the aspects that are influenced by the coal to be used. F'MC has been developing this process in pilot facilities since 1956 and in a modest sized plant in Kemmerer, Wyoming since 1960 (Figure I). This plant produces strong uniformly sized coke briquettes from a completely non-coking coal, namely Elkol, a sub-bituminous coal of the Adaville seam. Since operating commercially, over 300,000 tons have been produced, 90% of which has been used in electric phosphorus furnaces and some 10% of which went for trials in iron blast furnaces. We believe that this commercial use of non-coking coals is a unique experience in the history of coke manufacture.

Jan 1, 1975

By H. C. Harrell

The Tennessee Valley Authority began employing geophysical well logging for foundation investigations in October 1973. Since that time more than 3,000 holes have been evaluated for engineering purposes. The Tennessee Valley Authority has not actively used geo-physical well logging for exploration of construction materials, but we feel that much of the information derived from geophysical logs for foundation exploration is applicable to the construction materials industry. This paper will then discuss geophysical logging as applied to foundation engineering and, by implication, the feasibility of use in construction materials exploration. The use of geophysical logging and percussion drilling instead of coring has greatly expanded TVA's data acquisition capabilities and has also resulted in substantial savings in time and money. Economical boreholes are obtained through the use of large percussion track drills (Figure 1). This equipment is capable of drilling through the overburden, setting steel casing on the top of rock, and drilling the rock beneath the casing. Holes as deep as 400 feet (121.9 m) have been drilled by this method.

Jan 1, 1977

By F. J. A. van Ruitenbeek, M. Dalm

In the presented study test work was performed with near-infrared hyperspectral imagery (NIR-HI) on 36 ore samples from a South-American epithermal Au-Ag mine. The aim of the test work was to investigate if NIR-HI provides information about the alteration mineralogy of samples that can be used to predict their economic value. Mineral distribution maps were produced from the hyperspectral images by using correlation coefficients between the image pixels and a set of reference spectra. These maps showed that detection of mineralogy with NIR-HI can be used to distinguish; i) ore particles with low Au and Ag grades, ii) ore particles with high carbon contents, iii) ore particles with high sulphur contents.

Jan 1, 2015

By G. M. Wolfaardt, B. C. Qi

"From a lifecycle point of view, biologically digested sludge is a valuable product that should be reused if possible. Sludge may be applied to agricultural land for further sludge treatment and improvement of the characteristics of the soil. The characteristics of sludge that affect its applicability for soil conditioning include moisture content, pathogens, nutrients and metals. In this paper, the use of solid anaerobic digestion sludge of the lignocellulosic residues to condition soil was investigated in regards to nutrient composition, water content/retention capacity, hygienic quality (contamination of pathogenic bacteria) and heavy metal adsorbing/releasing characteristics of the sludge.It was found that the digested sludge had approximately 44.5% free and immobilized water and 46.9% bound water. The water-holding capacity of the sludge was high. This was a merit to apply the sludge to agriculture in dry areas. Anaerobic digestion under thermophilic conditions showed a promising disinfecting effect to the sludge, in contrast to the landfill digestion. The anaerobic digestion sludge could be considered as a humus-rich hygienic product that improves soil fertility and water holding capacity, nourishes plants and immobilizes heavy metals in the environment"

Jan 1, 2003

By Richard H. Spencer, Warren G. Bender

Since the passage of the Coal Mine Health and Safety Act of 1969, the Bureau of Mines has made many advances in mine communications. These efforts have resulted in the following developments and demonstrations: • Surface-to-surface electromagnetic transmission of baseband voice signals through overburdens as deep as 600 feet. This transmission was achieved with equipment from the Interim Mine Rescue and Survival System Program, and demonstrated that baseband voice communications could be obtained through these overburdens in the absence of mine-generated noise; that is, when the mine power system was shut off. However, during mine operational conditions, the mine-generated noise proved to be so large that effective baseband voice communications to the desired depths could not be effected. • The development of beacon transmitters for locating trapped miners. This work was again the outgrowth of the Interim Mine Rescue and Survival System. Extensions of this work have led to reliable detection and location of trapped miners to depths of 1000 feet. The system, which makes use of a loop antenna deployed where the trapped miner is located, uses low-duty-cycle, tone-burst transmission. Portable tuned receivers and loop antennas are used on the surface to determine the location of the trapped miner. An extension of this work has led to a call-alert paging system concept, wherein a transmitter, similar to that used in the trapped miner system, is used to audibly and/or visually alert key mine personnel carrying pocket receivers that they are wanted at the nearest mine telephone. In addition, a roof-bolt paging system has been developed, wherein commercial paging and mine carrier phone equipment are used in conjunction with a long-wire "roof bolt" antenna to page individuals and relay to them short voice messages.

Jan 7, 1975