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By Margaret Anne Stephenson

Today, in Australia, it is increasingly common to see agreements between Indigenous peoples and resource companies being achieved generally as Indigenous Land Use Agreements or agreements pursuant to the ?right to negotiation? process under the Native Title Act 1993 (Cth). Despite progress in this area, resource development on Indigenous lands is not without its challenges for both the resource proponents and the Indigenous parties. History demonstrates that resource development on Indigenous lands has produced struggles between the traditional owners of the land and the resource proponents. In Australia their relationship is generally defined by issues of access to land and assuring continued access to the land for the life of the project. In this context, divisions in Indigenous communities often emerge. The proposed resource project can have the effect of polarising members of an Indigenous community. It may be regarded by some traditional land owners as an advantageous opportunity for the community and by others as a hazard to country and culture. The process of agreement making has proved not only a test for the Indigenous community but also for the resource proponent. In this paper we undertake a contemporary case study of a proposed Australian resource related-development project on Indigenous lands. This project involved a multi-billion gas hub precinct proposed at James Price Point in the Kimberley region in Western Australia. The James Price Point proposal produced a litany of challenges for all parties. The traditional owners faced fundamental social and human rights issues, including a minority opposition to the project, the project's potential cultural heritage impact, the threat of compulsory acquisition of their native title interest by a State government due to an initial failure to settle an agreement, a fracture of their unsettled land claim and a minority rejection of the agreement ultimately reached. Additionally, the ?green? lobby also rejected the proposed gas hub on environmental grounds bringing the green lobby into direct conflict with both the traditional owners in favour of the project and the resource proponent. Ultimately, Woodside announced its decision not to proceed with the proposed gas precinct at James Price Point, in April 2013. In this paper we analyse the complexity of the James Price Point gas hub negotiations with the traditional owners which resulted in an Agreement that promised to deliver substantial benefits for the Indigenous communities. We question why such a favourable and beneficial agreement for the Indigenous community also produced the plethora of challenges and concerns and we consider how future negotiation processes could be better structured to avoid the difficulties that have confronted Indigenous land owners and resource proponents alike.

Aug 1, 2013

By A. M. Richmond

Introduction The apparent commonplace, and prosaic, nature of building-stones, lime, cement, gypsum, and clay products, and many other miscellaneous non-metallic minerals, such as abrasives, barite, diatomite, magnesite, mica, slate, salts, etc., and their everyday appearance and necessary in our lives, has removed much of the glamour, romance, and speculative attractiveness so frequently associated with our gold, silver, lead, zinc, and copper mining ventures. However, it will be readily appreciated, with but a brief study of the thirty-five or more non-metallic minerals and products which are mined, prepared, or are known to occur, in British Columbia, that the 'industrial minerals' industry in the Province has an abundance of interesting technical problems, is fraught with speculative possibilities, and, as such, fully deserves much more technical attention than it has hitherro received. The brief notes presented in this paper show, in summary form, the magnitude of the British Columbia industrial and non-metallic mineral industry; outline in synoptically form the principal deposits of non-metallic minerals presently known; and indicate in a general way a few of the possibilities which exist in the Province for the expansion of the industry. For convenience in presentation, the assembled material has been divided into four sections: 1.-Sraristical information 2.-Strucrural non-metallic minerals 3.-Miscellaneous non-metallic minerals 4.-Non-Metallic mineral possibilities in British Columbia 1. -Statistical Information The writer does not propose to dwell at length on the statistical comparisons and deductions which may be drawn from the four tables which have been compiled for this section of the paper, nor is it considered essential, as the figures present a most emphatic story in themselves.

Jan 1, 1935

By P. H. Agson Gani, T. Sitorus, N. P. Widodo

"PT ANTAM UBPE Pongkor underground mine use blasting to develop its tunnels which will cause poisonous and dangerous gases trapped inside mine. To analyze this case, a study of mine ventilation, the dispersion of carbon monoxide (CO) gas concentration and diffusion coefficient is commenced. At the end, the re-entry time formula will be determined. Results indicate that this study is site specific and could only be applied in the place this study executed. The aim of this study is to be further developed by applying Principal Component Analysis (PCA) to find a universal re-entry formula. KEYWORDS Mine Ventilation, Re-Entry, Smoke Clearing, Diffusion Coefficient, Carbon Monoxide Gas, Gas Dispersion INTRODUCTION Pongkor underground mine is using cut and fill as its mining method. Thus, its development and production processes require blasting to develop its tunnel. This process caused poisonous and dangerous gases spread and trapped inside the mine, one of them is carbon monoxide (CO) gas. CO is formed in an unbalanced reaction of explosives detonation and could be the cause of headache, blackout and death to people who inhale CO at certain concentration (McPherson, 2011; Hartman, Mutmansky, Ramani, & Wang, 2012). Mine ventilation system is installed in the mine to resolve this problem. Mine ventilation play an important role to disperse CO gas by absorb the poisonous/dangerous gases and deliver clean air into mine. The important parameter is diffusion coefficient, because diffusion is affecting particulates or gasses spreading from its sources throughout the mine. Diffusion coefficient is the total diffusion in axial direction of turbulent flow mainly by convection of bulk motion, advection and eddy diffusion, while the effect of molecular diffusion is appreciably negligible (Widiatmojo et al, 2015). Taylor (1953, 1954) develops a theory about the dispersion by inducing a slow stream of solvent into a capillary tube. Taylor used Reynolds assumption of radial diffusivity to be analogous with the transfer of the matter in turbulent flow as well as the transfer of momentum and heat. Then, Taylor proposed the formula of diffusion coefficient, D (m2/s), against pipe diameter and turbulent shear velocity are as follow:"

Jan 1, 2019

By B. W. Smee

Glacial lake sediments or glaciolacustrine deposits form a significant portion of the Canadian, Scandinavian and Russian landscapes. Furthermore, 50 per cent of the Archean volcanic belts within the Canadian Shield area are covered wholly or in part by these deposits. Because of the high electrical conductivity and low hydraulic conductivity of these compact sediments, the application of geophysical (electrical) and geochemical techniques in such areas becomes a difficult task. The presence of these sediments has therefore hampered exploration for metallic sulphide deposits in some of the most important metallogenic environments of Canada. Similar problems exist in some tropical countries, such as Australia, where the overburden may be very conductive. In this paper, the extent and provenance of the glaciolacustrine deposits within the Canadian Shield are described. The geochemical and geophysical factors that hinder exploration in the clay belts are reviewed, with case histories of successful and unsuccessful applications of some of these techniques. The most successful geochemical technique used within glacial clay belts is the sampling of lodgement till beneath the clay cover, and the analysis of the heavy mineral fraction of that till. Surficial sampling has not been successfully applied. Some geophysical techniques, more specifically electromagnetic and magnetic induced-polarization techniques, have detected mineralization beneath substantially deep clay or saline overburden layers. Some suggestions have been made, such as the use of anions in hydrogeochemical surveys and the use of wide-band multi-frequency EM systems. When implemented, they will hopefully make the current geochemical and geophysical methods more effective in exploration for base metal sulphides within clay-covered terrains.

Jan 1, 1979

By Paul Guliov

Preliminary investigations of stone resources were conducted in the La Range, Johnson Lake-Pelican Narrows-Deschambault Lake and Creighton-Amisk Lake regions of Saskatchewan. The work identified a rich variety of accessible, attractive and technically promising stone resources. Ordovician dolomites in various combinations of red, buff, yellow, grey and purple are very dense and take a very good polish. These are classified as marbles in the industry and some rival the famous marbles of Verona, Italy. A wide variety of attractive granites have been identified. Among these is a jade green stone (charnockite) and ornamental banded granites (gneisses). A dark greenish to black stone (amphibolite) with white and red veining resembles the well-known Verde Antique variety of Vermont and Italy and surpasses it aesthetically and in engineering properties. Some of these stones have been displayed at Canadian and United States expositions where they received an enthusiastic response from the international stone industry. More detailed evaluation and test quarrying of promising deposits are required. Such work could be rewarding to the industry as some stone varieties in the province have the potential for gaining international markets.

Jan 1, 2001

By E. Goris Cervantes

"A theoretical framework based on a detailed analysis of mine operations data from an oil sands mine in northern Alberta and the static simulation of truck cycle times are developed, verified, and validated in this paper. Implementation of this framework provides better results than existing tools that rely solely on manufacturer data. This, therefore, aids in efficient equipment planning for the life of the mine. The use of this framework to modify existing productivity curve estimation methods currently in use at the mine site is also proposed. This method replaces “loaded flat haul” with “loaded effective flat haul” in the productivity estimation. Validation of the model results in a 4% overestimation of productivity, versus an underestimation of more than 10% when using the existing in-house method. ¦ KEYWORDS Equipment planning, Life-of-mine (LOM) planning, Oil sands, Productivity, Truck cycle times RÉSUMÉ Un cadre théorique fondé sur une analyse détaillée des données relatives aux activités minières d’une exploitation de sables bitumineux dans le nord de l’Alberta et la simulation statique des temps de cycle des camions sont développés, vérifiés et validés dans cet article. La mise en oeuvre de ce cadre offre de meilleurs résultats que ce que proposent les outils existants, lesquels se basent uniquement sur des données des constructeurs. Ceci contribue donc à une planification efficace de l’équipement pour des projets relatifs à la durée de vie de la mine. On propose également de se servir de ce cadre pour modifier les méthodes d’estimation de la courbe de productivité actuellement utilisées sur le site minier. Cette méthode remplace le concept de loaded flat haul (la distance parcourue par des camions avec un chargement du point de collecte jusqu’au point de déchargement des résidus miniers) par celui d’effective loaded flat haul (la distance relative parcourue par des camions avec un chargement du point de collecte jusqu’au point de déchargement des résidus miniers) dans l’estimation de la production. La validation du modèle résulte en une surestimation de 4 % de la productivité, par rapport à une sous-estimation de plus de 10 % avec la méthode actuellement utilisée en interne. ¦ MOTS CLÉS planification de la durée de vie de la mine, planification de l’équipement, productivité, sables bitumineux, temps de cycle d’un camionINTRODUCTION One aspect that differentiates oil sands mines in northern Alberta from conventional hard-rock mining is the environment in which they operate. Due to ground characteristics, producers in the region experience roads with very high rolling resistance (RR) that, in turn, negatively affect haul-truck performance and greatly increase fuel consumption and emissions. Oil sands mining companies use some of the largest haul trucks in the world. In addition, oil sands mines cover more extensive areas than hard-rock pits, resulting in longer haul distances on roads made of comparatively more viscous material."

Jan 1, 2019

By S. Kline

The compositions of metamorphic minerals of the south limb of the Dore Lake Complex have been determined by microprobe techniques. Mineral assemblages typical of the greenschist facies occur in Mg-rich bulk compositions, but in Fe-rich rocks albite-epidote amphiboli te facies assemblages occur. Low oxygen fugaci ties and a general paucity of metamorphic fluids prevailed in most of the complex, but a higher oxygen fugacity is indicated near the Chibougamau Pluton, and a local abundance of C0z and Cl in fluids near the pluton is suggested by the presence of scapoli te. The metamorphic gradient overprinted on the complex near the Grenville Front is apparent in mineral chemistries as well as by the appearance of garnet. Chlorite becomes richer in Mg, and iron is fractionated more strongly into hornblende. The amphibole also increases in Alz03.

Jan 1, 1984

By W. G. Miller, J. D. Scott, D. C. Sego

ABSTRACT An overall study was conducted to evaluate the properties and processes influencing the rate and magnitude of consolidation for oil sands fine tailings produced using different extraction processes. As part of the overall study, a comprehensive description of physical and chemical characteristics of fine tailings generated by caustic and non-caustic processes was carried out. Ultimately, the influence of these fundamental properties on the compressibility, hydraulic conductivity and shear strength properties of the fine tailings was assessed. The characteristics of the fine tailings are presented in terms of index properties, mineralogy, specific surface area, water chemistry, liquid limits, particle size distribution and structure. A difference in water chemistry was concluded to be the cause of substantial differences in particle size distributions and degree of dispersion of the comparable caustic and non-caustic fine tailings. The degree of dispersion was consistent with predictions for dispersed clays established by the sodium adsorption ratio (SAR) values for these materials. A linear variation of increasing dispersion with increasing SAR up to a SAR value of about 40 has been suggested, above which fine tailings are completely dispersed. The observed dispersed or flocculated structures (viewed using a scanning electron microscope) supported the predictions based on SAR values.

Jan 1, 2010

By F. Awotwe-Appiah, P. Koshy, A. Y. Fosu, J. Dankwah, J. R. Dankwah

Ghana currently exports its bauxite raw without any value addition. Gradual depletion of high grade bauxite (with high alumina content) and the emergence of low grade bauxite (with high iron oxide content) calls for novel and inexpensive ways to recover alumina from these low grade ores. Bauxite users have indicated their willingness to pay 10% to 50% higher for a corresponding reduction in impurities by a similar amount. This project therefore investigates the carbothermal upgrading of the Ghana Awaso bauxite using waste polypropylene as reductant in a locally designed gas-fired furnace. Composite pellets of low grade bauxite sample (assaying 45% Al2O3) containing pulverised waste polypropylene were formed, oven dried, placed in fireclay crucible and fired for 30 minutes. The magnetic fraction after reduction was separated by a Low Intensity Magnet and weighed. It was observed that up to 97% of the iron oxides (occurring as hematite and goethite) could be separated into the magnetic fraction as magnetite leaving a nonmagnetic fraction with over 98% Al2O3 as opposed to the 45% Al2O3 in the as-received bauxite sample. This research direction provides yet another simple but effective way for simultaneously upgrading low grade bauxite and recycling waste polypropylene, whilst at the same time decreasing the amount of waste material generated as red mud after the Bayer process.

Jan 1, 2015

By Jack Craft

Local Environment Atmospheric conditions (or lack thereof) Drilling fluids are impractical Cuttings removal is a major concern Heat dissipation is a major concern Some tried-and-true mechanisms need air to function properly Gravity Low gravity means low downforce Microgravity means even less downforce Regolith Local dust may be highly abrasive Packaging for Spaceflight System mass is highly constrained The drill must fit within the spacecraft?s launch envelope Power is constrained

May 1, 2013

By R. J. Craig

Introduction All mining operations produce rock dust. Inhalation of rock dust, particularly if it has a high silica content, causes silicosis. Silicosis is, therefore, recognized as a hazard of the mining industry and has been made compensable throughout most of Canada. Most of the dust in any mining operation is caused by rock drilling and blasting operations and the movement and transportation of broken rock. Dust from blasting cannot be eliminated, but it can be controlled by means of increased ventilation, the use of water sprays, and the control of blasting hours. Dust from ore movement can be reduced by keeping the broken rock in a moist condition at all times. The dust from the rock drilling operation has been found to be the most difficult to control. Concentrations of dust caused by rock drills in stopes can usually be reduced to the safe minimum of 300 particles per cubic centimeter (p.p.c.c.) by diluting the air with increased ventilation. In development headings, where the machines are more confined, this is not always practicable. Therefore, the dust must be eliminated at its source. This paper deals with the reduction of dust from Leyner machines by adopting improved designs.

Jan 1, 1947

By Victor Azbe

Introduction Lime enters our daily life in many ways. Our building, chemical, agricultural, sanitary, and industrial endeavours depend on it to such a great extent that it could probably be called the most important inorganic chemical, and the extent to which it is used might be considered an index of industrial development. Industrial limes vary greatly in quality, due to internal structure and other characteristics. They may be good or bad, sensitive or slow to react. While improper manufacture may not greatly alter the appearance of the lime, it may affect its properties considerably and thus its suitability in the many processes in which lime is used. In some of the processes, one kind of lime is wanted, in others another. While the nature of the stone from which it is made has much to do with whether a lime is suitable or not, its burning and hydration are the crux of the matter. Up to not so many years ago, the knowledge of lime burning was rather imperfect and it is only relatively recently that its manufacture is approaching the state of a higher industrial art. This slow development was in part due to lime manufacture being scattered among many small concerns who, independently, either lacked the inclination or could not afford to strive for a higher technical development.

Jan 1, 1946

By A. H. Burns

"Regenerative and recuperative burner systems require advanced combustion techniques to minimize NOx emissions. Various methods of pollutant minimization and furnace design considerations are described. Cited examples are a large high temperature furnace and a small Zinc vaporizing furnace. The concept of total carbon footprint is introduced. The application of Biomass combustion as an effective method of cost and green-house gas (GHG) reduction is discussed. Practical considerations of scale, location and process limitations are discussed. Two examples of biomass fired equipment are cited. Ideal sites have large biomass resources available locally. Processed biomass fuels will be an important substitute for fossil fuel. INTRODUCTIONIn 1992, I presented a paper entitled Combustion Strategies In The Modern Industrial Environment (1992). At that time an abundant supply of cheap fossil fuel made many of the measures I talked about difficult to justify for anything but new equipment.Since 1992 we, as a society, have demonstrated an ability to accelerate the pace of industrial and societal change. The term industrial revolution applied to this age of incessant change is completely meaningless, implying a discrete moment in historical time. What our society has built is a system capable of unfettered, continuous and accelerating technological change. With this change comes an increasing demand for energy and materials.This year is the anniversary of the Titanic disaster, a moment in time when technological certainty met the caprice of nature and gave us a brutal reminder of what can happen to us if we underestimate that power (Mowbray, 1912). In the intervening interval we have regained the technological arrogance that was lost in 1912 bringing us back to the problems of climate change and the need for sustainable industrial activities.We use advanced mathematics to describe many complex systems, sometimes with disastrous results. For example there has been a recent attempt to model the global economy as a completely deterministic system. This premise is flawed at its foundation as human nature and emotion are indeterminate constants in the equations, yielding probabilistic solutions at best. As engineers we are all familiar with stiff problems. The solution to such a problem is meaningless and we have all had the misfortune to live through and rue the effects of that miscalculation over the last few years."

Jan 1, 2012

By C. S. Parsons

Introduction Up to the present, the operation of small mills for the treatment of gold ores has not been favoured in Canada to the extent that it has in other countries. For instance, a list of the operating properties in Southern Rhodesia, published in The Rhodesian Mining Journal of November, 1934, shows for the month of September, 1934, that there were over 500 small mills treating less than 50 tons per day, and the majority of these between 5 and 25 tons. They are operated by individuals, syndicates, and small mining companies. It is presumed that the operations are profitable, although from the published figures of the tonnages treated and the yields, it is difficult for one familiar with Canadian operations to understand how this can be possible, in the majority of cases. Most of these small mills employ stamps with plate amalgamation and with, occasionally, tables to produce a concentrate. Enquiries have been received from many parts of the world respecting milling practice suitable for small gold mines and the type of plant used in Canada. The tenor of these enquiries leaves the impression that the majority of the writers assume that the practice would be similar at all small properties. This, of course, is not the case. Conditions vary widely, and what would be a suitable mill for a typical Nova Scotia ore would not necessarily be wholly adaptable to many ores in Ontario, Quebec, or British Columbia. This paper has been written with the intention of inviting discussion, and it is hoped that, by such discussion, the subject will be more fully dealt with than has been possible in the time at the disposal of the writer. Only more or less standard principles and practices have been dealt with, and, purposely, no reference has been made to plants using mills of the Hadsel, the Nutt, or the Gibson type. As there is available but little reliable information on the costs of installation and operation of small mills, it is also hoped that those contributing to the discussion of milling practices for small mines will be in a position to give these data for the benefit of those contemplating the erection of small plants in Canada. Although it is difficult to generalize, it can be said that there are three types of gold mills commonly used at small mines: (1) Amalgamation and Gravity Concentration; (2) Amalgamation and Flotation; and (3) Cyanidation.

Jan 1, 1935

By Ben Habermann

"The object of the work described in this paper was to increase the understanding of the relation that capillary pressure of a rock, hydro-dynamics, and accumulation of oil in stratigraphie traps have to one an-other. The hydrodynamic oil-water tilt equation is derived by considering the two vector gradients involved: (1) buoyancy of oil in water and (2) hydraulic gradient.Recent theories show the necessity for oil to have a continuons phase in the reservoir rock in order to mi-grate; this fact applies to hydro-static as well as to hydrodynamic conditions. Hydrostatically, the displacement pressure of the rock deter-mines the amount of oil that can be trapped behind a permeability barrier. If the buoyancy of oil in water exceeds the displacement pressure, oil will migrate up-dip; an oil trap will be formed where displacement pressure is greater.In stratigraphie traps the pressure drop caused by moving water is positive when its direction is down-dip, helping accumulation; and it is negative when its direction is up-dip, forcing the oil into the tighter section of the reservoir. Theoretically, pro-vided we have data such as: (1) the displacement pressure of an up-dip permeability pinchout, (2) density difference between the oil and water in place, and (3) the direction and magnitude of the hydrodynamic gradient (if any), the possible extent of a stratigraphie oil accumulation down-dip can be predicted.To test the above theory sample cores from three wells in the Denver Basin were analyzed and the oil column that could be held under hydro-static conditions was calculated. After the hydrodynamic influence was considered, the results were compared with actual field data.The significant fact shown by this investigation is that the calculated oil column in one reservoir very closely approximates the actual extent of the oil column in a well. Also in accordance with the theory, the capillary pressure caused by the buoyancy of the oil column exceeded the measured displacement pressure on core samples from another productive field. For very tight shaly sand and questionable oil shows, the interpretation of data is very critical, as shown by experiments on core samples from a third field."

Jan 1, 1960

By Minghao Hu, Hongbo Zhao, Jun Wang, Wenqing Qin, Rui Liao, Central South University

"In the present work, X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS) analysis and electrochemical analysis were carried out to investigate the intermediate species and electrochemical dissolution process of chalcopyrite in the presence of sulfur and iron oxidizing microorganisms. For bioleaching of chalcopyrite by the sulfur oxidizing microorganism Acidithiobacillus caldus, the redox potential was always lower than the appropriate value and chalcopyrite was mainly directly oxidized to polysulfide (Sn 2-), thus resulting in low copper extraction. As for bioleaching of chalcopyrite by the iron oxidizing microorganism Leptospirillum ferriphilum, chalcopyrite was mainly directly oxidized to polysulfide at the initial stage where redox potential was lower than the appropriate value and resulted in low dissolution rate. At the middle stage where redox potential was appropriate (about 350–480 mV vs. Ag/AgCl), chalcopyrite was mainly transformed to intermediate species of Cu2S rather than polysulfide, thus resulting in high dissolution rate. At the later stage where redox potential was higher than the appropriate value, chalcopyrite was mainly directly oxidized to polysulfide which caused the later passivation of chalcopyrite. Finally, a model of electrochemical dissolution process of chalcopyrite in the presence of sulfur and iron oxidizing microorganisms was provided.INTRODUCTIONBiohydrometallurgy is considered as one promising mineral processing technique in processing low grade ores due to the advantages of simplicity, low cost and eco-friendly. Chalcopyrite (CuFeS2) is the most abundant copper-bearing resource, accounting for appropriately 70% of the known reserves in the world, while is recalcitrant to bio-hydrometallurgy mainly due to the coated passivation layer (Klauber, 2008; Li, Kawashima, Li, Chandra, & Gerson, 2013). However, the detailed dissolution and passivation mechanisms of chalcopyrite bioleaching are still uncertain. The microorganisms assisting chalcopyrite dissolution can be mainly classified into three types, including mesophilic microorganisms (e.g., Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans), moderately thermophilic microorganisms (e.g., Acidithiobacillus caldus, Sulfobacillus thermosulfidooxidans and Leptospirillum ferriphilum), and extremely thermophilic microorganisms (e.g., Metallosphaera sedula, Sulfolobus sp., Acidianus sp., and Sulfurcoccus mirabilis). Moderately thermophilic microorganisms have a better prospect in the future industrial application of chalcopyrite bio-hydrometallurgy (Olson, Brierley, & Brierley, 2003; Rohwerder, Gehrke, Kinzler, & Sand, 2003). Hence, investigating the detailed dissolution and passivation mechanisms of chalcopyrite bioleaching by moderately thermophilic microorganisms is of important significance, which will provide essential information for promoting chalcopyrite bioleaching by moderately thermophilic microorganisms in laboratory or industrial plant."

Jan 1, 2016

By M. Abouhamad

According to the Canadian Urban Transit Association (CUTA), 140 Billion CAD is required to maintain, rehabilitate, and replace subway infrastructure between 2010 and 2014. The current practice adopted by transit authorities for prioritizing subway stations for rehabilitation is based on the station structural needs. While this classification is reflective of station condition, other factors, such as station size, location and passenger capacity, play an important role. The criticality of a station is an index that represents the functional importance of a station depending upon a set of identified factors. The system criticality is based on several attributes, such as station location, size, and nature of use. This paper presents a novel method of clustering subway stations for rehabilitation priority based on their criticality level. The different stations in a subway network are rated according to their relative importance against predefined attributes. The weights and scores of the attributes are computed with the help of experts and current subway network data. The analysis is done using the Fuzzy Analytic Network Process (FANP) to accommodate the subjectivity of human judgment as being expressed in natural language which entails ?fuzziness? in real-life problems and account for the interdependency between the selected attributes. The output of the model is a criticality based clustering of subway stations. The proposed framework helps authorities prioritize stations for rehabilitation and highlight stations with more criticality for a more robust asset analysis.

Aug 1, 2013

By C. E. Baltzer

This paper highlights the electric power situation in Canada, and introduces brief explanation of the salient differences between electrical practice in the United States and Canada. The availability of bask energy in the two countries is touched on, also the hydro versus thermal outlook as applying to Canada. De-v2lopment of thermal-electric power is dealt with in some detail, followed by Canada's thermal-electric power requirements, present and future. The fuel requirements for steam-electric generating plant are assessed on the basis of a survey recently made, and the location and size of the major thermal plant operations are given. Fuel contractual obligations on the part ?of suppliers and consumers are mentioned. Finally, an opinion is expressed in regard to the types of f.uel in ?demand on a regional basis with emphasis on the need for coal in the several areas dealt with.

Jan 1, 1958

By T. R. Kostecki

"Instrumented rock bolts are effective tools for assessing the reinforcement and condition of immediate roofs; however, instrumentation can have relatively high costs, which can be justified by high reliability and repeatable and representative data measurements. The instrument’s durability and operational life are of great importance, along with accuracy, applicability, and usefulness. This paper develops reliability models for three instrumentation technologies used in slotted rebar, drawing data from studies at five underground coal mines. Three case studies demonstrate instrument applicability and usefulness. Finally, two types of instrumented rock bolts are used to determine the direction of bend and maximum bending strain. RÉSUMÉ Les boulons d’ancrage instrumentés sont des outils performants qui permettent d’évaluer la consolidation et la condition des toits immédiats. L’instrumentation peut cependant se révéler très onéreuse, des coûts qui se justifient par sa fiabilité élevée ainsi que par des mesures de données reproductibles et représentatives. La durabilité de l’instrument et sa durée de vie opérationnelle sont très importantes, de même que son exactitude, son applicabilité et son utilité. En s’appuyant sur des données issues d’études menées dans cinq mines de charbon souterraines, cet article développe des modèles de fiabilité pour trois technologies d’instrumentation utilisées pour des barres d’armature nervurées. Trois études de cas démontrent l’applicabilité de l’instrument et son utilité. Enfin, deux types de boulons d’ancrage instrumentés sont utilisés pour déterminer la direction de la flexion et la contrainte de flexion maximale.INTRODUCTION Using instrumented rock bolts to monitor strain changes in a rock bolt array allows engineers to understand the per-formance and effectiveness of the rock reinforcement system and the response of the rock mass to such support; however, instrumentation remains a niche solution for solving complex ground-control problems—particularly for underground coal mines, which is where they are needed most. From 2000 to 2016, fall-of-ground fatalities still accounted for an average of approximately 30% of the total annual underground coal mine fatalities in the United States alone (United States Department of Labor, 2018). These tools would also be useful for deep hard-rock mining conditions. The main reasons for the lack of widespread use are not only cost but also accuracy, applicability, implementation procedures, intrinsic permissibility, and reliability (Peng, 2015). As a result, measurements of coal mine roof behaviour using instrumented rock bolts are quite scarce, not widely published, or inadequately presented to provide a seamless understanding of a roof’s response to support."

Jan 1, 2018

By G. J. Birnie

Introduction The preparation of the following paper has been undertaken in the belief that a description of the development methods and equipment used at Lake Shore, at the present time, will prove of general ? interest. Working depths of nearly a mile and a half in shaft sinking and of more than one mile for stoping operations have imposed problems not encountered at shallower horizons. Among the problems contributing to the difficulty of mining at extreme depths might be mentioned: Rock pressures Ventilation Hoisting Shorter work period at the face Geological considerations In the main, the effects of these factors add to the difficulty of mining at depth, but it is not entirely true to say that each must necessarily become more pronounced as mining operations proceed to greater depths. Corrective measures may, in some cases, retard the effect and in others may even relieve some of the difficulty. It is proposed here to discuss these features in the light of the experience at Lake Shore, and to present, in some detail, the current practice in shaft sinking and in driving ore and waste passes, raises, drifts and cross-cuts.

Jan 1, 1950