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By Meyer Klein

Decision theory is the formal theory of the logic of decisions in view of the decision maker's objectives, preferences, I beliefs, and available information, It usually deals with weighty economic problems involving irrevocable (or costly to reverse) decisions. Capital investment planning problems constitute an instance par excellence for application of the decision theory concepts. Decision theory as it is presently conceived has evolved in recent years. At first it concentrated on decisions in the face of total lack of information and on games with intelligent adversaries. The results of these efforts proved theoretically interesting, but practically of little applicability. In the last few years, stress has shifted to the introduction of subjective probabilities and preferences, and the results have been eminently successful in applications both in government and with- in business firms in the resolution of complex problems.

Jan 1, 1970

By C. A. Heiland

THIS year's review of geophysical activities has a somewhat different complexion than usual. With the ending of the war, the time seems opportune to supplement the customary report on operations and discoveries in oil and mine exploration by a review out-lining the contributions of geophysicists to the. war effort. To give as much space as possible to the latter, presented as Part 2, some of the usual review features have been omitted from the statistical section, given as Part 1 immediately following.

Jan 1, 1946

By David L. Borusiewicz, M. Suri Surendra

"Abstract Helical piles have been used as anchors and for supporting lightly loaded structures as a method of underpinning, etc in the past. Recently, helical piles are being used to support new structures because of their simple installation process using relatively light and mobile equipment. This paper presents the results of evaluation and design performed for the temporary support of existing piers during a bridge rehabilitation project.INTRODUCTIONThe helical screw foundation was invented and patented by Alexander Mitchell in England in 1833. He installed screw piles to support lighthouses in the tidal basins of England. Many applications in the earlier years in the USA were in North Carolina and in Florida to support lighthouses (in coastal plain deposits). A lighthouse of similar foundation design is still in use at Key Biscayne, Florida.In the USA, the helical piles were reintroduced as foundation elements for electrical transmission towers. Helical piles were also used for anchoring guys of self supported towers and as tie-backs for excavation support systems. Typically, helical piles are being used for supporting lightly loaded buildings and for underpinning buildings undergoing distress as a means of remediation. The helical piles are not commonly used in the transportation industry.HELICAL PILESHelical pile is a segmented deep foundation system with helical bearing plates welded to a central steel shaft. Load is transferred from the shaft to the soil through these bearing plates. Central steel shafts are available in either a square shaft (Type SS) or a round shaft (Type RS). The Type SS series are available in 38 mm to 57 mm square sizes. The Type RS series are available in 73 mm to 114 mm diameter sizes. Type SS-RS combinations are also available for compression applications in soil conditions where dense/hard soils must be penetrated with softer/loose soils above the bearing strata.The leading segment consists of a shaft with one or more helical plates that are welded to the shaft. The plates vary in diameter from 203 mm to 355.5 mm and have a thickness of 9.5 mm or 13.7 mm. Typically the plate diameter increases from the bottom of the shaft upward. A helical bearing plate or helix is one pitch of a screw thread. All helices, regardless of their diameter, have a standard 76 mm pitch. Being a true helical shape, the helices do not auger into the soil but rather screw into it with minimal soil disturbance. Helical plates are generally spaced a distance of two to three times the diameter of the plate directly below in order for them to function independently as individual bearing elements. A typical detail of helical pile is shown on Figure 1."

Jan 1, 2014

By Julie Dénommé

Today few in business would argue with the idea that we are living in a world that is Volatile, Uncertain, Complex, and Ambiguous. Coined VUCA by the US Army War College, these four words define the ?turbulence? and ?continuous white water? that the business literature has been documenting for the last decade. This VUCA world became even more relevant to business in 2007 when the Institute for the Future fellow Bob Johansen published the idea of transforming VUCA into Vision, Understanding, Clarity, and Agility. We call this VUCA Prime (VUCA'), and place an infinity loop (8) between them to show their dynamic interaction. This paper presents an exploration of the impact of VUCA 8 VUCA' on business and the conditions under which these dynamic forces help to successfully navigate change.

Oct 1, 2010

By Tom Treleaven

The success of any blast is dependent on the accuracy of the blast design and the field controls used on the shot. This point cannot be over emphasized because when the geometry is not measured and/or field controls are not properly implemented, it can often have devastating effects on the final blast results. Thus drilling accuracy, tiont row burden control, explosive confinement, energy distribution, explosive selection, timing and structural geology become critical parameters in the design of successful blasts. Understanding the actual dynamics of the blast and why certain results were achieved is the fast step in optimizing a blast design. As stated by R. Frank Chiappetta, “Of all the blast monitoring systems available today, high speed videography still remains as the best stand alone instrumentation system for blast diagnostics.” Over the past years I have analyzed hundreds of blasts using either high-speed lowcams (500 frames per second) cameras or standard digital (30 frames per second). These analyses confirm, without a doubt, that shot geometry, in combination with structural geology, is the most important factor in overall blast results. Drilling accuracy is the single most important component in efficient blasting. Having equal mass associated with an equivalent energy is the basis in which blasts are designed. When drilling inaccuracy or borehole deviation occurs, not only is the energy unevenly distributed, but the basis of all design calculations becomes invalid. Over the past several years, quarry and mining operations have employed the use of boretracking measuring devices to measure borehole deviation and hole toe locations. In cases of operations using top hammer drills, it was discovered that the amount of deviation was significant and far greater than they believed they had. Set up error, improper drilling techniques and bit wear were some of the contributing factors. Through video anaysis of boretracked blasts, blast results were directly linked to drilling ..accuracy. The comparisons here took into account blast design, energy factors and hole sequencing.

Jan 1, 2000

By William B. Plank

IN this paper are presented the results of a complete statistical survey of the enrolment, courses and degrees, and the employment situation of recent graduates in all of the 46 institutions in the United States, including Alaska, and four of the six schools in Canada that grant degrees in mineral technology. The data were collected by the writer by means of a questionnaire in December, 1933, to which all the institutions, except one, replied. Included also are data of a similar study made by the writer in May, 1933, for the S. P. E. E. summer session of mining and metallurgical teachers at the University of Wisconsin and published in the Journal of Engineering Education for December. 1933. Some of the data of a paper of the writer's entitled, "The Trend of Mineral Engineering Student Enrolment in the United States," read at the A. I. M. E. meeting on Feb. 16. 1931, are given for comparison. Acknowledgment is made to all the administrative officers of the institutions who took the time from their busy lives to supply the in- formation asked for. Their fine cooperation has alone made possible these two surveys with a completeness of detail never before attempted

Jan 1, 1934

By H. Boghosian

This paper presents the design and construction of a deep basement in a steeply sloping site in glacial till in Glasgow city centre. Existing foundations, adjacent structures and services, in tandem with asymmetric loading, presented particular challenges in the planning, execution and design of the project. The construction methods and temporary works, analysis by the Finite Element method and monitoring carried out are all described.

Jan 1, 2006

By Bernard Lewis

This report summarizes the fundamental research and technical studies conducted by the Explosives Branch of the Bureau of Mines from July 1, 1943, to June 30, 1949. It is the thirteenth of a series of annual reports, which have aimed to bring to the reader a resume of the research results that have appeared in published form during each fiscal year. The work of the Explosives Branch covers a number of activities - explosives research, explosives testing, flame and combustion research, flammability of gases and vapors, dust-explosions research, and technical studies in the experimental mine. An important part of the work of the branch is fundamental research to advance our knowledge and understanding of explosion processes. Considerable emphasis has been placed on studies of ignition and flame stabilization, as it is felt that an understanding of these processes should assist materially in alleviating explosion hazards in coal mines. The results are also finding important application in the development of jet propulsion. Studies of the explosibility of gases, vapors, and dusts saving thousands of lives and are preventing the destruction of much property. In innumerable instances in which potential explosion hazards exist, safe operating procedures have been recommended from data taken in the Laboratory. Aware of the value to national security of research results of combustion, flame, and explosion, the Army, Navy, and Air Forces are actively supporting important phases of this fundamental research.

Jan 1, 1950

By Michael K. Watkeys, Charlesworth. E. GUY, Jacobus E. Potgieter, Anhaeusser. Carl R., Roger L. Gibson, Alexander F. M. Kisters

Abstract - Intrusive features of cupriferous noritoids from the deeply eroded Proterozoic granite-gneiss terrane of the Okiep Copper District in South Africa illustrate the emplacement of basic magmas into a mid- to lower-crustal environment. The small, easterly trending intermediate to basic intrusions of the so-called Koperberg Suite display a wide variety of geometries, occurrence and emplacement modes, including dike-, sill- and plug-like bodies. Coeval granulite-facies metamorphism, partial melting and ductile deformation of country rock gneisses during intrusion of the basic magmas led to emplacement and dilation processes of the intrusions which differ significantly from those described for dikes and sills at shallow crustal levels. Regional tectonic stresses are largely negligible due to very low differential stress (?1 - ?3) during deformation and intrusion, which permits emplacement at high angles to the principal compressive stress and which follows favorably inclined structural anisotropies. Dilation of the basic intrusions is largely determined by compositional differences of host rocks and occurs by thermal erosion, i.e., assimilation of wall rock gneisses. Low length-to-width ratios of basic to ultrabasic dikes and predominantly diaper -like outlines of mesocratic bodies are indicative of low viscosity contrasts between the mafic magmas and high-grade metamorphic host-rock gneisses. Buoyancy-controlled ascent of the basic to intermediate intrusions is expressed by a broad compositional zoning of basic bodies with respect to the granite-gneiss stratigraphy. Various intrusion modes within the stratigraphic column of the granite-gneiss sequence reflect a lithological and structural stratification of the seemingly homogeneous granite-gneiss terrane.

Jan 1, 1994

By Helen D. Robinson

Traditional practice to resist large lateral loads on foundations is the use of large diameter caissons, battered driven piles, or battered micropiles. Dense urban construction environments, however, limit the usefulness of these systems due to the close proximity of below- and above-grade obstructions. This paper presents two micropile construction projects in the United States where a complex scheme of battered micropiles and grade beams was developed to counteract large lateral loads at the foundation level. The paper also presents a procedure used to design vertical micropiles for large lateral loads, which can greatly simplify the design of foundations subject to significant lateral loads in urban environments. A design example shows a case where vertical micropiles were used to support allowable design lateral loads greater than 80 kip per micropile.

Jan 1, 2010

By J. N. Geyer

During the early stages of the mining industry of the United States an apparently inexhaustible supply of high-quality, easily accessible coal made the product cheap and the attendant mining methods wasteful of recoverable coal. Because coal from advance places could be mined with less effort and a large outwit obtained as the entries advanced, much of the coal left in pillars to support the roof was lost. Squeezes often developed in these mined-over areas, or, if pillars were of sufficient size to-prevent squeeze, the roof would be so weakened by long exposure that any pillar recovery was extremely hazardous. As the value of unmined coal increased, a high recovery of the available coal became necessary. Numerous plans were tried during the period that followed, some of the methods proving successful while others were complete failures or only partly successful. As a better knowledge was pained of the roof strata and its behavior, however, pillar mining became more successful and methods suited to special roof conditions were developed.

Jan 1, 1933

By Daniel I. Carey

Current and potential dragline reclamation usage was evaluated for the U.S. coalfields based on data gathered and analyzed during field surveys, literature reviews and contacts with manufacturers. It was concluded that current wining plans have been adapted to federal and state strip mine and reclamation laws in ways which limit the potential for drag line reclamation systems at active mine sites. At abandoned conventional contour mine sites in steep-sloping areas such as central Appalachia, however, it was found that dragline reclamation systems have great potential application and may be the only practical solution to many reclamation problems. Alternative dragline systems were examined for restoring abandoned sites, and it was concluded that a tower excavator system offered superior characteristics and should be evaluated and developed under field conditions. A testing program was developed to provide a framework for the monitoring and analysis of cost, production and environmental data during a field demonstration of a tower excavator system.

Jan 1, 1981

The placer gold industry has experienced a roller-coaster history incorporating four major boom eras. The first, 'hand-methods' boom arose in the mid-19th Century from application of an old idea in new places around the globe. The subsequent hydraulic mining, bucket dredging, and 'hydraulic excavator-portable plant' booms each arose from application of new ideas in old places around the globe, ie in places where gold had been found during earlier booms. The new ideas that heralded the second, third and fourth booms were all significant advances in excavation technology. These enabled the industry to target the known deposits that were too deep, too wet, too small, or too low-grade for recovery by earlier boom methods. Relatively few new deposits or new deposit styles arose from the 'history book' exploration approach, so the number of known deposits to which each of the boom methods were applicable was limited. Consequently, the first three booms were each followed by significant periods of industry decline, and the fourth boom is currently waning inNew Zealand. Further decline is not inevitable and can be avoided by changing to a knowledge-based exploration approach similar to that adopted by the hard rock gold industry in the 1970s. Such an approach could easily herald the next placer gold boom.   Most of the relatively coarse, easily won alluvial gold in proximal and medial reaches of the active placer systems is gone. However, a substantial alluvial gold resource remains in the distal reaches of active systems, and in ancient placers formed onshore and on the continental shelf during previous sedimentary cycles. The resource in these deposits probably exceeds the total New Zealand placer production to date. Successful development of these placers requires application of robust geologic models for the formation and distribution of the placers through time, and advanced exploration technology that has not been used before in New Zealand. Nevertheless, the knowledge and technology required to explore and mine these deposits is available now. Many of these deposits contain a large proportion of problematic gold types that are difficult to recover with the commonly used gravity technology without sustaining significant losses. Despite advances in recovery technology in last few years, too much emphasis is placed on the incorrect assumption that gold size is the primary control on recovery efficiency. Other gold particle parameters, especially particle shape, exert a much greater control on whether gold will be saved or lost to the tails, and must be considered in the design of recovery technology and configuration of recovery circuits.

Jan 1, 2003

JAMES A. BARR Consulting Engineer Mt. Pleasant; Tennessee Washington, D.C. BEHRE DOLBEAR G COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4. N. Y. BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia LENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 210 La Arcada Bldg. Santa Barbara, Calif.

Jan 1, 1952

JAMES A. BARR Consulting Engineer Mt. Pleasant. Tennessee Washington. D.C. BEHRE DOLBEAR G COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4, N. Y. BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 210 La Arcada Bldg. Santa Barbara, Callf.

Jan 1, 1952

By IPMI Educational and Scientific Foundation

It is with great pleasure that we announce the availability of this fourth issue of the IPMI Journal, a publication of the International Precious Metals Educational and Scientific Foundation. This digital peer reviewed publication has been created as a vehicle for the sharing of technical information related to the science and technology of precious metals. Since 1976, the International Precious Metals Institute has championed the exchange of information of critical importance to the precious metals scientific and commercial communities through its various communications vehicles. This has included instructional videos, annual conference symposia, special topic committee meetings, regional seminars, and professional and student achievement awards. Due to the breadth of important topics related to all aspects of precious metals, it has been the vision of the IPMI to provide a publication available to the general public that would become a key source of pertinent topics containing high quality publications by experts in their fields of study. Historically, the IPMI has attracted world renowned experts in many fields (including Nobel Laureates Henry Taube, Ei-ishi Negishi, Robert Grubs, Professor Ben Feringa, and David MacMillan) in the dissemination of discoveries, inventions, and industry proven practices. Such information has a total value greater than the sum of its parts as seemingly unrelated innovations from distinct focus areas can be adapted to solve problems. Because of this important characteristic of information exchange, we have decided to create a digital journal, available to the general public, that will not only communicate state of the art discoveries and sound practices, but will also review historical communications from the IPMI’s archives that have value and use even in today’s environment. On behalf of the members and leaders of the IPMI, we hope you will find value in this new publication.

Dec 1, 2020

[JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington, D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4, N. Y. BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Montieello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 210 La Arcada Bldg. Santa Barbara, Calif.]

Jan 1, 1952

By Linda L. Chasko, Charles P. Lazzara, Gary Braselton, Ronald S. Conti

Preparedness is an important element of any underground mine's strategic plan in dealing with an unexpected event, such as a fire. A fully implemented fire preparedness and response plan is essential in reducing the probability and seriousness of a mine fire. This report describes the development of an underground coal mine fire preparedness and response checklist (MFPRC). The checklist is a data collection instrument for profiling both the fire prevention and response capabilities of a mine site and usually requires 3 to 4 days to complete. The checklist encompasses conditions, procedures, and equipment that have frequently been identified as the primary or contributing causes of underground coal mine fires. At least 1 day is needed underground to evaluate the water system. This entails measurements of water flows and pressures at fire hydrants, and water throw distances of fire hose and nozzles at several locations (mains and branch lines). A few of the other topics that are discussed with mine personnel include detection and suppression systems, combustible materials, mine rescue and fire brigades, and firefighting equipment. The MFPRC was developed by the National Institute for Occupational Safety and Health (NIOSH),Pittsburgh Research Laboratory. Under a Cooperative Research and Development Agreement (CRADA) with Cyprus Amax, Twenty mile Coal Co. (Oak Creek, CO), the checklist was field tested and further refined. Additional field tests were conducted at several other operating coal mines.

Jan 1, 2000

The evident need to improve the reliability of fluid power systems in underground coal mining equipment prompted the U.S. Bureau of Mines, and later the Department of Energy, to contract with the Fluid Power Research Center at Oklahoma State University for a research project to develop methods for achieving this end. Since the work of the contract was completed at about the time DOE was relinquishing its underground coal mining projects to BOM it was decided to issue the final report under 80M cover. The contract revealed that the major causes of poor reliability were: (1) poor overall system design, (2) poor component contamination toleranace, (3) poor system filtration, and 4) poor maintenance practices stemming from a lack of defined maintenance procedures and enforcement of same. This report demonstrates the variability of the reliabilities of components of similar performance description when subjected to standard tests. Improved design procedures are recommended and the information needed to specify and select components whose reliability is predictable and optimum without sacrifice in performance or significant increase in envelope size.

Jan 1, 1983

By Enrique Monge Gordillo

Si bien el fierro es el metal más barato en la industria minera, el incremento de su demanda y agotamiento gradual de sus depósitos, genera que su costo se eleve progresivamente. Por tal motivo, el objeto del presente texto describe el proceso de consumo del hierro y acero y su repercusión en el mercado occidental a través de cuatro capítulos: El primero, refiere a la demanda de hierro y acero tanto en Estados Unidos, los depósitos en Québec y Labrado en Canadá, el tratamiento y comercio de minerales de hierro; el segundo, a las operaciones mineras en Canadá y América Latina como las de Canadá, Venezuel, Brasil, Chile, Perú, México, Colombia, Cuba, Santo Domingo, Argentina, entre otros países; el tercero, revisa las plantas de hierro y acero en América Latina como las de Brasil, México, Chile, Argentina, Colombia y Perú, mientras que el último, refiere la industria de fierro y acero en los Estados Unidos, producción de fierro cochino y costos e importaciones del acero.

Jul 20, 1959