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By B. D. Sparks, I. E. Puddington, F. W. Meadus

The continuous separation of bitumen from Athabasca tar sands, with a high clay content, has been demonstrated. Recoveries of 95 per cent or higher have been obtained. Further processing of this product, to produce an accept-able type of crude oil, would require less heat than currently used in the hot-water process. Also, by comparison, substantial savings in equipment and operating costs are indicated.

Jan 1, 1971

By P. Mengé

The covering of a hydraulically filled goethite pond is discussed from a geotechnical point of view. The characteristics of the goethite were defined in order to allow a detailed study of the procedure for the construction of the cover on top of the soft material and a verification of the stability of the cover and side slopes after construction. These characteristics and the main results of the studies are given, as well as the experiences and observations made during the execution of the work. Finally, the monitoring plan, during and after construction, is also discussed and some results are given. The 'Design and Construct' contract form was used to allow the contractor to choose the optimum and most economical method to realize the closing of the pond, based on his experience with similar projects. The works were carried out between mid 2003 and the end of 2004. The paper will, amongst others, discuss the special method of working that had to be developed to allow the covering of the whole pond in a relatively short time period, without soil improvement methods such as vertical drains or stabilization by in situ treatment. Fill material was used to establish a platform on top of the soft material so that the cover liner and finishing layer could be installed on top of the fill layer. The 'floating roof' principle was used; subsidences were allowed to occur during the installation of the impermeable top liner and soil cover.

Jan 1, 2006

By Douglas H. Brown

Cadmium and other 'minor' metals in Canada tend to remain inconspicuous given the prominence of the country's massive production of other minerals. This same reality is reflected in the accuracy and deficiency of quantitative data concerning the sources of supply and demand for these metals. It is the intent of this paper to identify the nature of some of these difficulties and to reconstruct a more accurate description of Canada's production and consumption of cadmium, based on the results of recent surveys undertaken by the Mineral Policy Sector of Energy, Mines and Resources Canada and Noranda Sales Corporation Ltd.

Jan 1, 1978

By F. M. Doyle, G. Sidhu, A. J. Dussault, A. Raygani

There is a growing demand for rare earth metals for use in high strength permanent magnets, most notably Nd2Fe14B. Rare earth metals are extremely reactive, with reduction potentials around -2.5V SHE, and are conventionally produced by molten salt electrolysis. The current work was done to investigate an earlier report of electrodeposition of a neodymium ferroalloy from aqueous solution, to determine whether this approach could be an environmentally and economically competitive commercial approach for producing feedstock for permanent magnets. Such a process would be analogous thermodynamically to the Castner- Kellner process, in which aqueous sodium chloride brine is electrolyzed in cells with mercury cathodes. Metallic sodium forms an alloy (amalgam) at the cathode, thereby lowering the activity of the metallic sodium significantly below unity and making the reduction potential of sodium significantly less negative than the standard reduction potential. Here we report the effects of Nd/Fe ratio in the electrolyte, current density, temperature and two different complexing agents, glycine and cysteine, on the composition and morphology of the electrodeposits, along with current efficiency. The energy needed to produce neodymium as Nd:Fe alloys by aqueous electrodeposition was compared with values estimated for production by molten salt electrolysis and the thermodynamic energy requirement.

Jan 1, 2014

By P. J. Routledge

THE purpose of this paper is to discuss the practical aspects of locating gravel deposits and of establishing efficient, portable concrete aggregate beneficiation plants for use on construction projects where limited amounts of high-quality gravel and sand are required. Certain projects are listed, in order to demonstrate the wide variety of problems encountered. Routledge Gravel Contractors Limited, North Vancouver, have supplied concrete aggregate for construction projects in British Colum-bia since 1957. In tl1at year, in sup-plying aggregate for a small project at a site on the northern coast of British Columbia, our quote was as follows: Concrete aggregate to specifications, f.o.b. scow, North Vancouver$ 1.75 per cu. yd. Scowing charges to site. $16.00 per cu. yd. At that time, our company realized that more attractive quotations could be submitted if local gravel was utilized where available. Port-able equipment was then acquired and a simple screening plant (Figures 1 and 1a) was at first used. This was later replaced by heavier, more versatile equipment. The use of suitable equipment, the keeping of cartage to a mini-

Jan 1, 1962

By A Hitchen

A general outline is given for the determination of copper, nickel, cobalt, zinc, lead, cadmium, bismuth, manganese, uranium, molybdenum, vanadium, sulphate and fluoride by polarographic or amperometric methods in a variety of ores or metallurgical products. The detection of oxygen in gas mixtures by an amperometric method used as a safety device is also discussed. Introduction I N this paper, a general outline will be given of the polarographic and amperometric methods used for the chemical analysis of various ores and metallurgical products in the Chemical Analysis Section of the Extraction Metallurgy Division of the Mines Branch. The methods to be discussed will be confined to those based on the use of normal D.C. polarography and will not include those methods which utilize a cathode-ray, square wave, pulse or A.C. type of polarograph. For the sake of convenience, ? the polarographic methods will be discussed according to the type of supporting electrolyte employed, as the same electrolyte may serve to determine more than one element in more than one type of ore. Amperometric methods will be discussed according to the element to be determined rather than

Jan 1, 1965

By G. A. Witwicki

"The Thyssen Mining Group of Companies has successfully applied ground freezing technology to numerous projects throughout Europe and North America for over 100 years. Recently, the aspect of data acquisition and data verification has received greater focus.Thyssen Mining has been engaged in several relatively deep shaft sinking projects over the past five (5) years, all of which have required ground freezing to successfully sink through water bearing rock. To safely and economically sink through a quantity of water similar to Saskatchewan’s Potash Mines, it is imperative to understand freeze wall thickness and growth rate.Critical to understanding freeze wall thickness and growth rate, is the collection of accurate data as well as the interpretation of those data. The data can then be utilized to gain a better understanding of the freeze wall growth rate in active projects as well as to provide data to be utilized in modeling for future projects.This paper elaborates on the installation and operation of the data acquisition system utilized at the Newmont Leeville project, Nevada’s first frozen shaft project. In addition, this paper elaborates on the methodology developed by Thyssen Mining to manipulate the freeze wall data derived through the data acquisition system.The successful incorporation of the new system of collection and analysis of freeze wall data for the Leeville Project has given Thyssen Mining a high degree of confidence in the understanding, as well as prediction, of the ground conditions during shaft sinking.This paper will include:•,A brief description of ground freezing and its objective;•,An overview of previous data acquisition methods employed;•,Current data acquisition methods;•,Installation requirements; and,•,Data manipulation and presentation methods."

Jan 1, 2015

By Bryan Wilson

Background ?Nickel Rim South Mine started production ramp-up in Q2, 2009. ?The main dewatering pumps were put into use in August 2009. ?3 Feluwa?multisafe?positive displacement pumps ?1700m single lift pumping ?Reliability has been an issue due to the amount of slimes and fibers (from shotcrete) at the pumps. ?Critiqued internal dewatering system to solve some issues we were having with our sumps Findings 1.Much of the final dewatering system was not in place. a)Temporary pain. Difficult to say something is not working when the system was not yet in place as per design. b)Not enough capacity to handle slimes within the system. 2.Need to address issues with the final design: a)Ongoing costs: The end design has operating costs of $2.5 million b)Scoops in Sumps: The end design relies on scoops to be used for cleaning the sumps c)Slimes Recovery: The system mixes 3 different products in the sumps along with the fibers d)Pump repair costs: The existing Tsurumi pumps are too light duty for our slimes

Nov 1, 2011

By M. Reda

Inorganic oxidizing agents of the type MeOx-z such as Chromate, Vanadate, Tungstate, and Molybdate... etc. are widely used as corrosion inhibitor. In non acidic solution these oxidizing agent are reduced on the surface of the meta, according to OX + m e + p H20 Red + n OH" In which y = (n-m)/m. The purpose of this publication is to show that for many metals the value of y for any oxidizing agent determines the possibility of that oxidizing agent being an inhibitor or activator for the corrosion process. The inhibition efficiency for other ions such as Pertecnetate and Tellurate which have not been extensively studied can be predicted. A mathematical, equation was derived to express the relationship among the concentration of oxidizing agent, degree of retardation of the corrosion process I cord cor ° (ratio of corrosion current in the solution containing inhibitor to the base solution) , ionic strength of the solution and the coefficient y. The validity of y and the mathematical, equation were verified by many experimental, works on various metals such as zinc, aluminum and steel. Al, the above research works are based on the published research works of Prof. Mikhailoviskii (from 1979 til, 1998) from the Russian Academy of Science.

Jan 1, 2010

By K. Trapani

"The study undertaken aims to investigate an ice stope heating and cooling system for its potential to be implemented in sub-arctic mines, as a low carbon alternative to conventional natural gas and refrigeration chiller systems. Its performance was simulated for a years’ worth of data, taking into consideration hourly temperature data. Results showed that to supply the required heating and cooling loads, the ice stope system had to supplement its heating with natural heating. The techno-economic performance of this system was compared to that of a conventional heating and cooling system in a mine, with the ice stope thermal storage system hawing the lowest annuitized cost and significantly lower carbon emissions.INTRODUCTIONConventional heating and cooling, in a mine is implemented using natural gas heaters and chiller refrigeration systems respectively. This results in a significant portion of energy consumption in underground mines attributable to ventilation (De Souza, 2015), including the conditioning of the air to ensure that temperatures do not exceed work comfort standards (ACGIH, 2011). Especially at depth where heat could become a significant issue. An ice stope thermal storage, using ice as the storage medium is being proposed as an alternative to provide the heating and cooling—with the ice creation resulting in heating and the ice melting providing the cooling required. A techno-economic investigation of the two systems is undertaken to identify the capital and operating costs for the two systems, and to assess the ice stope’s potential to be considered a low cost and carbon solution for heating and cooling of mines in sub-arctic climates.NATURAL STORAGE SYSTEM – CONCEPT DEVELOPMENTThe concept for the natural storage system is developed from the ice stope at Frood-Stobie Mine, ON, Canada (Stachulak, 1991). The ice stope was developed for mine air heating, with the heating occurring by spraying warm return service water onto the cold intake air—resulting in the air temperature increasing and ice being created in the stope. In summer this ice was melted by passing warm air on top of it, resulting in slight cooling of the air but no significant temperature difference which could allow effective cooling. A schematic of the Frood-Stobie Mine ice stope is provided in Figure 1."

Jan 1, 2019

By Y. M. Jubeli

"Gamma-ray spectrometry, an effective tool in geological mapping, was used to de?ne boundaries between various lithological formations in three adjacent areas of Central Syria, namely, the Syrian Desert, Ar Rassafeh Badiayat and the Northern Palmyrides mountains.This paper describes the role of an airborne gamma spectrometric survey which was originally undertaken to assist uranium exploration. Interpretation of the total count data obtained through the survey has led to signi?cant modi?cations and corrections to the previously published distribution map of the palaeogene phosphate rocks.Another important result of the survey is the discovery of four previously unknown phosphorite horizons in the Rasm Al-Aawabed area of the Northern Palmyrides. In addition, previously unknown phosphatic horizons are outlined in the other study areas. The importance of this technique as an effective prospecting method, not only for U but also for exploring for the economically important phosphorite formations in Syria, is emphasized. Furthermore, its role in geological mapping is stressed, especially in areas that lack suf?cient geological data."

Jan 1, 1997

By R. D. Prettie

Wood preservation may be defined as the art of protecting wood from decay. In its broadest sense, however, it includes a much wider field. It might be more properly de-fined as the art of protecting wood from destructive agents, such as decay, insects, marine borers, mechanical wear, etc. The earliest data on record for the preservation of organic bodies is found in Egyptian manuscripts. The bodies which we call mummies were impregnated with antiseptics, of which the principal were natrum (sodium sesqui-carbonate), sodium chloride, and sodium sulphate. After being steeped in the solution, they were subjected to either a boiling or baking process in a bituminous preparation. The first attempts in Europe to preserve timber were made by the Greeks and Romans. They extracted essential oils from the juniper and cypress trees, and either rubbed these oils into the wood they wished to preserve, or bored thousands of small holes in the wood and poured the preservative oil into the holes. The famous statues of Jupiter and Diana were carved out of wood. The ceremony of pouring in the preservative oil by the High Priests was a religious pageant of great importance, of which there are many records.

Jan 1, 1926

By Y. M. Jubeli

"Abstract - Gamma-ray spectrometry, an effective tool in geological mapping, was used to define boundaries between various lithological formations in three adjacent areas of Central Syria, namely, the Syrian Desert, Ar Rassafeh Badiayat and the Northern Palmyrides mountains. This paper describes the role of an airborne gamma spectrometric survey which was orginally undertaken to assist uranium exploration. Interpretation of the total count data obtained through the survey has led to significant modifications and corrections to the previously published distribution map of the palaeogene phosphate rocks.Another important result of the survey is the discovery of four previously unknown phosphorite horizons in the Rasm Al-Aawabed area of the Northern Palmyrides. In addition, previously unknown phosphatic horizons are outlined in the other study areas. The importance of this technique as an effective prospecting method, not only for U but also for exploring for the economically important phosphorite formations in Syria, is emphasized. Furthermore, its role in geological mapping is stressed, especially in areas that lack sufficient geological data."

Jan 1, 1997

By R. A. Halet

"The Malartic Gold Fields mine is a good example of the association of ore deposits with a major fault zone. It also exemplifies the control exerted by the physical and chemical character of the host rocks on the localization of orebodies.The mine is in Fourniere and Dubuisson townships, Abitibi county. It is 6 miles east of the town of Malartic, 9n the main highway and railway from Noranda to Val d'Or.The discovery of the mine is due largely to the enterprise of the late J. P. Norrie, who organized the present Company in 1935. The ground is entirely covered by overburden, but Mr. Norrie believed that the extension of the Cadillac-Malartic 'break', the principal ore-bearing structure of the district, would be found on this group of claims. This belief was supported by the discovery of gold-bearing float in the area, and was confirmed by a dip-needle survey and a few pilot diamond drill holes that showed that the favourable Malartic greenstone band passes through the centre of the property.In this way the most favourable area for prospecting was narrowed to a zone 2 ½ miles long by ½ mile wide underlain' by greenstone. The remainder of the property is underlain by sedimentary rocks, which, from experience elsewhere in the camp, were not considered as promising. However, as the entire surface is covered by deep overburden, the location of orebodies even within this more or less restricted area could be accomplished only by a long campaign of diamond drilling. Systematic diamond drilling began in 1936.The contacts of the greenstone band were considered to be the most promising places to begin the work, and the early drilling was concentrated on the south contact, because the orebody of the East Malartic mine, 4 miles to the west, had been discovered on this structure and it was reasonable to hope for a repetition of these conditions. Although the south contact was very thoroughly explored, with a certain amount of encouragement, the work did not prove the existence of deposits of ore grade, and attention was shifted to the north contact zone of the greenstone band. In this locality much more promising results were obtained, and a number of good orebodies were outlined."

Jan 1, 1954

By J. Ita, F. Malekzadeh

"Multi-scale simulation in coupled fluid flow- geomechanical systems is a computationally efficient method for numerically solving large poroelastic systems. When using multi-scale methods, care must be taken in ensuring consistency when information is exchanged between systems that have a different discretization. Here a method is presented which provides consistency between the pore pressure being calculated on a fine scale fluid flow domain and upscaled to the coarser scale geomechanical domain and the pore volume change being calculated on the coarse geomechanical domain and down-scaled to the fine fluid flow domain. Central to this process is the characterization of the mechanical properties of the poroelastic system at both scales.Another advantage of the method presented here is that it is applicable to hydraulically disconnected but laterally drained (i.e. multi-porosity) layered systems as well as hydraulically connected, layered systems. Thus it can be used in geological situations where thin shale streaks or hardpans impede flow between laterally extensive, hydraulically conductive units. This is significant as the pressure evolution of such a hydraulically disconnected, laterally drained system can be very different than a hydraulically connected one as shown here. INTRODUCTIONA multi-scale treatment of fluid flow and deformation is a key enabler when simulation of poroelastic phenomena is limited by computational resources. As the spatial domain of the geomechanics model is usually larger than the fluid flow model, it is desireable to use a coarser discretization in the geomechanical model compared to the fluid-flow model. This type of multi-scale simulation requires a consistent up-scaling of pore pressure from the fine scale fluid flow model to the coarse scale geomechanical model and down-scaling of pore volume change from the geomechanical model to the fluid flow model (see Figure 1)."

Jan 1, 2015

By R. Matusewicz, A. Kaye

Ausmelt Top Submerged Lancing (TSL) Technology has gained widespread commercial acceptance in non-ferrous applications, including the processing of lead and zinc primary concentrates and secondary (post-consumer) materials. TSL is highly flexible and efficient, and is one of the few technologies which can process primary and secondary feeds, and use varying fuels, to deliver high recoveries and excellent environmental performance. With the recent high value of both lead and zinc, and an escalating awareness of the sustainable use of resources, focus on the processing of secondary feed material sources has surged. Ausmelt Technology has proven to be well suited to the economic recovery of values, with twenty-two (22) Ausmelt furnaces processing lead and zinc bearing feed sources now in operation, under design or construction. This paper describes Ausmelt's progress in the fields of lead and zinc processing, and developments in new processing areas such as EAF dust processing and linking to innovative hydrometallurgical technology. Ausmelt has recently committed to the Whyalla Zinc project as the owner/operator of a facility for the treatment of zinc bearing secondary feeds. This project is due for start up in the first quarter of 2008.

Jan 1, 2008

By D. A. Trotter

"This paper traces the main advances in mine lighting from neolithic times to the 1960s. The earliest lights consisted of reeds or strips of wood soaked in grease. As man's knowledge increased, the oil lamp, the candle, kerosene, acetylene and finally electricity have allowed him to see where no natural light could penetrate. These advances in technology, however, did not come easily. Many false starts were made and great dedication was required by a few lighting pioneers to overcome the many technical difficulties that were encountered. The lighting of coal mines in particular caused unique problems, as there was the ever-present threat of methane explosions. Advances in mine lighting will continue, but these advances are only possible because men like Davy, Wolf, Marsuat and Edison paved the way.IntroductionMan's first efforts at mining consisted of merely picking rock off the surface of the earth. The sun was his only source of light. The early mines of the Neolithic age were simply vertical pits, 5 to 8 m deep. In order to follow an orebody, miners began to dig horizontally from the bottom of these pits, and as work progressed the need for additional light became apparent. With the discovery of the light-giving properties of fire, man was no longer dependent on natural light. Figure 1 gives an impression of the earliest artificial mine lighting used.Early Evidence of Mine LightingCarbonized residue from wood chips which had been inserted into rock cracks can be found in early Neolithic workings. The mines at Krzemionki Opatowski in Poland contain very narrow low tunnels that were lit in this fashion and were worked from 2300 to 1800 B. C. The wood had to burn downward to provide light and because wood burns poorly in this position, the chips were probably soaked in animal fat to make them burn more easily."

Jan 1, 1982

By J. L. Feng, F. Zhang, S. K. Hu

"Cracking is one of the most serious damages in tunnel linings, which is often observed by in-situ inspection to tunnel engineering. It is difficult to better characterise for the deformations from continua to discontinua by the traditional continuum mechanics due to emerging of crack initiation, crack propagation, and coalescence, at several scales. In this paper, the process of failure that was from micro damage to macro crack in concrete tunnel linings under experimental load conditions, was quantitatively simulated by the combined finite-discrete element method (FDEM). Comparison of the simulating results with that obtained by the full-scale test of concrete lining under different loading conditions in the literature was respectively good agreed and shows that such FDEM technique is appropriate to model the continuousdiscontinuous problems. The present study indicates that the FDEM technique could be benefit to quantitatively evaluate the stability and damage level of tunnel lining system. INTRODUCTIONMost damage to tunnel linings is caused during the construction phase, which can emerge in a form of single macro cracks or even large-scale spalling. The cause of such damage is mostly the occurrence of, either impermissibly large contact stresses resulting from high thrust loads combined with production and installation tolerances in the segments resulting in a geometrical lack of fit (Maidl et al., 2012; Transportation Research Board, Basic Research and Emerging Technologies Related to Concrete Committee, 2006), or unallowable tensile/shear stresses appearing in the tunnel linings under complicated loading conditions (Ansell, 2010). Such a macro failure phenomenon may also be regarded to as a result of growth, coalescence, initiation of microcracks in tunnel linings due to the complicated loading action, and even potentially lead to an instability or collapse of the local or entire tunnel system. Much work has been devoted to investigate for the characters of micro and macro cracks, the influence factors of damage patterns, the settlement of a tunnel, the width, length and density of lining cracks, especially from classifiedly and qualitatively (Wang, 2010; Huang et al., 2013). However, the safety evaluation of tunnel is definitely required to not only inspect in situ, but further also quantify computing and analyzing for tunnel lining systems, so as to provide a global viewpoint of process of the tunnel deformation, which aims to help for subsequent decisions, e.g. controlling traffic flow or immediately repairing task. Additionally, the design of lining thickness and its structural analysis that is mostly determined by previous experience and similar construction examples is also needed to be improved."

Jan 1, 2015

By G. W. Poling, G. W. Hawthorn

"""Unassayable gold and platinum group metals"" have come into vogue in the 70sand 80s in certain jurisdictions as a means of perpetrating fraud. Usual arguments are that a particular ore is not amenable to ""conventional fire assaying"". Explanations for unassayable gold usually revolve around: evaporation of micron-size gold; vaporization of organic gold complexes; volatization of gold halides; alloying of gold with PGM's which prevents fusion or alloying which prevents collection .This paper reviews several of the myths and truths of gold and PGM assaying with the knowledge that not a single mine operatesin thefree world producing gold from unassayable ore.INTRODUCTIONAccurate analyses of exploration data and estimation of ore reserves are two of the most important functions of professional geologists and engineers in mine development. The problems encountered become particularly acute when dealing with precious metal values where very low grade deposits (in the range of 0.0 I Troy oz per ton or - 0.2 ppm (g/t) by weight) sometimes are economic or constitute ""ore"". To emphasize this ""scarcity effect"", a gold assay of 0.4 g/t (0.01 T oz/st) would result from the presence of a single 420 J.tm (35 mesh) gold flake (which weighs I milligram) in a 5 kilogram siliceous sample.The current high gold price and the prospects of high profit margins awaiting exploitation of even very low grade gold deposits, has spawned a sizeable group of incompetent or fraudulent gold assayers. These ""assayers"" will often report significant precious metal values where no such values occur. Failures of legitimate assay labs to confirm these ""significant"" assays are often attributed, by the charlatan, to their capability of detecting ""unassayable gold"" while the check assayer cannot. Geologists and engineers lacking detailed knowledge of sampling and assaying techniques are often hard-pressed to convince a gold-fever aroused company executive or investor-client to abandon a property on which attention-grabbling values have been reported, often by more than one laboratory. Professionals engaged in such evaluations must acquire an understanding of contemporary precious metal sampling and assaying techniques . Only then can they determine whether misrepresentation of values have been perpetrated"

Jan 1, 1989

By M. L. F. Paullo, S. Cristian Mejia, D. Roehl

"Rock fracture simulation most often presents non-linear behaviour due to loss of material integrity and strain concentration in the fracture zone. These strains generate local instabilities that propagate to the global system of equilibrium equations, generating convergence problems of the numerical solution. Often, in such cases, analyses in the post-critical regime are unfeasible. To overcome the numerical difficulties associated with problems of stiffness loss in the post-critical regime control methods, also called continuation methods, are employed. Among them are the arc-length method, the energy control method and the indirect displacement control method. These methods are employed in conjunction with a Newton- Raphson scheme for the solution of non-linear systems of equations. However, depending on the system instability, convergence in not guaranteed even with very small increments. In the present work these control techniques are investigated in combination with cohesive elements to simulate rock fracture. The constitutive model employed with the cohesive elements represents stiffness degradation through a damage law, which leads to serious convergence difficulties as reported in the literature. Here the continuation methods mentioned are applied to a Mode I rock fracture problem and to hydraulic fracture simulations. The effectiveness of the different continuation methods is compared.INTRODUCTIONThe process of rock fracture induced by the fluid pressure is called hydraulic fracturing. The propagation of a hydraulic fracture is a complex process, which is basically defined by the mechanical deformation of the rock, the fluid flow within the fracture and the fracture propagation itself (Mokryakov, 2011). In the works of Bendezu et al. (2013), Chen (2012) and Carrier et al. (2012), vertical hydraulic fracture propagation is modeled by cohesive elements with traction-separation law. The softening behavior of rock in post-critical regime is demonstrated by experimental testing and is characterized mainly by high strains and low stresses (Crowder and Bawden, 2004). This nonlinear behaviour can arise due to material nonlinearity, such as micro-cracking and damage, leading to softening behaviour (Chandrakant, S.D., 2012). The cohesive fracture model considers in its formulation the softening behaviour that most rocks present in post-critical regime with propagation criteria."

Jan 1, 2015