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Vol 223

Geology
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Plume tectonics – myth or reality?

The paper is dedicated to the role of mantle plumes in the formation of large igneous provinces. From different regions of the world facts are mentioned that contradict key points of plume tectonics. Closer attention is paid to classical volcanic provinces on Hawaiian islands and in Iceland, as well as to Siberian and Deccan Traps, oceanic plateau Ontong Java, Central Atlantic magmatic province, Alfa and Mendeleev Ridges in the Arctic Ocean. A conclusion is drawn that plumes are a special case of mantle-lithospheric flows, which according to deep geophysics are often located horizontally which leaves out their plume origin. Heated masses of mantle substance under young volcanic regions or rift zones of mid-ocean ridges do not emerge from the depth in the form of a straight column, but rather have arbitrary shapes, skewing to the sides and having outgrowths, offshoots, spherical bulges. Vertically rising flows of hot magma (plumes) are not a cause, but an effect of a lithospheric split and rise of magmatic substance due to decompression. A conclusion is made that it is unproductive to exaggerate the shapes and sizes of plumes and use them to explain all the diversity of endogenous processes.

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Yu. I. Daragan-Sushchov (2017) Plume tectonics – myth or reality?. Journal of Mining Institute. Vol 223. p. 3. DOI: 10.18454/pmi.2017.1.3
Geology
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Combined 2D inversion of electrotomographic and audio-magnetotellurgic sounding data to solve mining problems

Electrical methods of exploration are widely applied in prospecting and estimation of ore mineral resources. It is not always that geoelectrical models obtained in the course of interpretation of different types of electric and electromagnetic sounding are in line with each other. This leads to difficulties in geological interpretation of electrical exploration results. In single cases a geological model can be built that with great precision satisfies data from different electrical explorations, for instance, results of geometric and inductive electromagnetic soundings. For this purpose an algorithm of combined inversion of electrotomographic and audio-megnetotellurgic sounding data has been developed and implemented by A.E.Kaminskii in software ZondRes2D. Advantage of combined inversion has been shown for investigation of sections up till 400-500 m deep on synthetic models and actual field data. 

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V. A. Kulikov, A. E. Kaminskii, A. G. Yakovlev (2017) Combined 2D inversion of electrotomographic and audio-magnetotellurgic sounding data to solve mining problems. Journal of Mining Institute. Vol 223. p. 9. DOI: 10.18454/pmi.2017.1.9
Geology
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Deposits of gold-quartz formation in the Priamur province

A description of gold-quartz formation deposits in the Priamur gold province is presented. Prevalence of gold-quartz deposits defines metallogenic profile of the province and presence of numerous rich placers. Deposits are attributed to frontal, middle and near-bottom parts of the ore pipe. Frontal part of the ore pipe contains a major part of the deposits. They are small and consist of scattered quartz, feldspar-quartz and carbonate-quartz veins. The ore is characterized by erratic percentage of gold, bonanzas can be found. Gold is free, ranging from fine to big grains and small nuggets. It is associated with arsenopyrite, galenite, sometimes with antimonite. Among trace elements can be copper, mercury, antimony and arsenic. Prevalence of frontal deposits in the province points to significant prospects of finding a rich deep mineralization in the middle part of ore pipe. Middle part of the ore pipe contains intermediate and small deposits. Ore bodies are often represented by veined and veinlet-disseminated zones, sometimes zones of metasomatites. For gold-quartz ores, free native gold can commonly be found, usually of fine and very fine grain size. Among ore minerals, apart from arsenopyrite, pyrite and galenite, scheelite is frequently observed. Small deposits of near-bottom ore pipe are quite rare. Ore bodies are represented by quartz veins and zones of metasomatites. Gold is mostly free, of fine and super fine grain size. The prevailing trace element is mercury. Attribution of gold-quartz deposits to a certain part of ore pipe can facilitate more precise estimation of their pros pects. In its own turn, this will allow to choose more favorable objects for further evaluation. 

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V. A. Stepanov, A. V. Mel'nikov (2017) Deposits of gold-quartz formation in the Priamur province. Journal of Mining Institute. Vol 223. p. 20. DOI: 10.18454/pmi.2017.1.20
Geology
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Possibilities of seismic exploration for crystalline basement study

Possibilities of seismic methods of reflected and refracted waves have been examined for the purposes of detailed study on crystalline basement structure. Investigation of depth and structure of the basement plays an important role in the exploration of various deposits. Sedimentary cover is usually associated with oil and gas reserves. Ore deposits are formed in the basement rocks, basement splits and structure of its surface have a genetic relation not only to ore minerals, but also to oil resources. Reflection seismology is one of the main seismic methods of investigating structural geometry of the sedimentation mass, forecasting its material composition and possible hydrocarbon reserves. However, its possibilities for investigating crystalline basement are limited. Basing on many years’ experience of reflection seismology and physical modeling it has been identified that actual roughness of basement surface limits the obtainable amount of waves reflected from it. Possibilities of reflection seismology for basement structure study are mostly related to investigation of discontinuous faults as diffraction objects using diffracted waves. Method of refracted waves combined with modern procedures and material processing aimed at getting dynamic seismic sections holds much significance for the basement study, especially in the process of surface mapping and, to a lesser extent, in investigating discontinuous faults. Combining seismic methods of reflected and refracted waves in basement study increases reliability of forecasting its geological structure: in particular, its surface can be well defined by means of refraction seismology, and zones of discontinuous faults are identified from diffraction objects using both reflection and refraction methods. As a result of applying both reflection and refraction seismology, an opportunity arises to carry out detailed analysis of basement structure and to predict its oil and gas content.

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A. N. Telegin (2017) Possibilities of seismic exploration for crystalline basement study. Journal of Mining Institute. Vol 223. p. 30. DOI: 10.18454/pmi.2017.1.30
Mining
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Impact of the shape of geological contact on mining losses in the process of near-contact zone development

In Russia development of mineral resources is carried out on a truly grand scale, and mining industry is in its essence a basic sector, supporting and facilitating the development of national economy. It predetermines the need of safe and responsible attitude towards riches of our subsoil – mineral resources. With this in mind, one of the key requirements to extraction technologies is minimization of mining losses and ore dilution. The biggest ore losses in the mining block take place in the process of development of contact areas between the ore body and surrounding rocks, due to differences between development pattern and surface of geological contact. Complexity of the contact between ore and surrounding rocks is traditionally characterized by so called «stochastic contact zone». Technological difficulty of extracting ore from the ore – wallrock contact is determined by volatility of geometric parameters in «stochastic contact zone» in the plane of geological contact. Current paper focuses on the issues of standard-setting for mining losses and ore dilution in the process of near-contact zone development. A method is suggested to estimate standard values of losses and ore dilution in stochastic zones. Authors have developed an algorithm of defining the shape of the contact. In the stochastic zone the contact can have a rectangular, sinusoidal, serrate and straight-line shapes. Research has established a relation between the contact shape and amounts of mining losses and ore dilution, formulas to calculate standard values are presented. Using suggested method, standard values for contact ore losses can be obtained in a quicker and more reliable way. 

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G. S. Kurchin, S. A. Vokhmin, A. A. Kytmanov (2017) Impact of the shape of geological contact on mining losses in the process of near-contact zone development. Journal of Mining Institute. Vol 223. p. 37. DOI: 10.18454/pmi.2017.1.37
Mining
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Open-pit mining of lignin waste storage

The purpose of this paper is to develop performance criteria for fleet selection in surface mining of lignin as a raw material for factory-made fuel. The East Siberian Biotechnical Plant (ESBP) proposes to close the Lignin Waste Storage (LWS) at Tulun, Irkutsk Region of Russia. The LWS is a 9.6 ha facility used for the long-term storage of hydrolysis lignin and some fly ash. The project provided whole-year open-pit mining of lignin storage with one mining ledge within 3 years. Productivity – 1500 t/day or 447 000 t/year. Excavated lignin will be stockpile on the Pellet Plant territory for later processing. Part of this closure effort would involve constructing an artificial reservoir on the place of LWS. The objectives of this project were as follows: determine equipment needs and develop optimal procedures for the lignin excavation and transportation. Lignin moving may include site preparation, excavation, transportation and road surfacing. Lignin excavation is conduct by using techniques similar to those used for open-pit mining of peat. For this project, the excavator is the most important piece of equipment required for lignin removal and handling. The mining process consist of excavating the lignin (using Kraneks ЕК-270LC) and hauling it to pellet plant via six off-road tractors&semitrailers (John Deere 7730& ISON-8520).

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A. V. Mikhailov (2017) Open-pit mining of lignin waste storage. Journal of Mining Institute. Vol 223. p. 44. DOI: 10.18454/pmi.2017.1.44
Mining
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Research of compression strength of fissured rock mass

The article examines a method of forecasting strength properties and their scale effect in fissured rock mass using computational modelling with final elements method in ABAQUS software. It shows advantages of this approach for solving tasks of determining mechanical properties of fissured rock mass, main stages of creating computational geomechanic model of rock mass and conducting a numerical experiment. The article presents connections between deformation during loading of numerical model, inclination angle of main fracture system from uniaxial and biaxial compression strength value, size of the sample of fissured rock mass and biaxial compression strength value under conditions of apatite-nepheline rock deposit at Plateau Rasvumchorr OAO «Apatit» in Kirovsky region of Murmanskaya oblast. We have conducted computational modelling of rock mass blocks testing in discontinuities based on real experiment using non-linear shear strength criterion of Barton – Bandis and compared results of computational experiments with data from field studies and laboratory tests. The calculation results have a high-quality match to laboratory results when testing fissured rock mass samples. 

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A. G. Protosenya, P. E. Verbilo (2017) Research of compression strength of fissured rock mass. Journal of Mining Institute. Vol 223. p. 51. DOI: 10.18454/pmi.2017.1.51
Mining
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Methodology of reducing rock bump hazard during room and rillar mining of North Ural deep bauxite deposits

The article describes practical experience of using room and pillar mining (RAPM) under conditions of deep horizons and dynamic overburden pressure. It was identified that methods of rock pressure control efficient at high horizons do not meet safety requirements when working at existing depths, that is explained by changes in geodynamic processes during mining. With deeper depth, the geodynamic processes become more intensive and number of pillar and roof failures increase. When working at 800 m the breakage of mine structures became massive and unpredictable, which paused a question of development and implementation of tools for compliance assessment of used elements of RAPM and mining, geological, technical and geodynamic conditions of North Ural bauxite deposits and further development of guidelines for safe mining under conditions of deep horizons and dynamic rock pressure. It describes reasons of mine structure failures in workings depending on natural and man-caused factors, determines possible hazards and objects of geomechanic support. It also includes compliance assessment of tools used for calculations of RAPM structures, forecast and measures for rock tectonic bursts at mines of OAO “Sevuralboksitruda” (SUBR). It describes modernization and development of new geomechanic support of RAPM considering natural and technogenic hazards. The article presents results of experimental testing of new parameters of RAPM construction elements of SUBR mines. It has data on industrial implementation of developed regulatory and guideline documents at these mines for identification of valid parameters of RAPM elements at deep depths. 

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D. V. Sidorov (2017) Methodology of reducing rock bump hazard during room and rillar mining of North Ural deep bauxite deposits. Journal of Mining Institute. Vol 223. p. 58. DOI: 10.18454/pmi.2017.1.58
Mining
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Development of methods of analytical geometry of a sphere for solving geodesy and navigation tasks

The article develops ideas and formulas of analytical geometry for spherical surface of the Earth globe in relation to main tasks of global geodesy and navigation. It examines peculiarities of sphere inner geometry and properties of its primary, secondary and higher-order curves. It was proved that spherical hyperbola and parabola are spherical ellipses with specific parameters. The Cartesian ordinates were introduced into the sphere and the relation between them and polar spherical coordinates was established. With the help of central projection of sphere points on tangential plane the corresponding elliptical plane with beltrami ordinates was introduced. The article describes main formulas of analytical geometry for projected elliptical plane, which correspond to geometry of projected sphere. It also introduces several formulas for primary, secondary and higher-order curves for this sphere.

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G. I. Khudyakov (2017) Development of methods of analytical geometry of a sphere for solving geodesy and navigation tasks. Journal of Mining Institute. Vol 223. p. 70. DOI: 10.18454/pmi.2017.1.70
Mining
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Technological problems and fundamental principles of methods of engineering-geocryological exploration during construction and exploitation of wells in permafrost rock mass

The article describes peculiarities and complicating factors when constructing wells in cryolithic zones. It also presents fundamental principles of methods of pilot parametric drilling for complex exploration of engineering-geocryological conditions of multiple-well gas production platforms. The article describes peculiarities of geophysical examinations within the complex of parametric drilling for clarification and correlation of log sheet, and identifying non-commercial gas reservoirs and interpermafrost head oil-filed water horizons in permafrost rock mass. We defined main ecological issues of parametric drilling and presented potential environment pollutants from well drilling in cryolithic zones. It concludes a list of factors, which should be considered during gas well drilling in northern zones for meeting the «safety – sustainability – low waste» criteria.

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Z. N. Cherkai, E. B. Gridina (2017) Technological problems and fundamental principles of methods of engineering-geocryological exploration during construction and exploitation of wells in permafrost rock mass. Journal of Mining Institute. Vol 223. p. 82. DOI: 10.18454/pmi.2017.1.82
Oil and gas
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Research on technical and technological parameters of inclined drilling

An analysis of operational capabilities of inclined drilling equipment and technology is presented. Two options of rotary drilling are reviewed as technical and technological solutions, facilitating construction of wells with difficult profiles. The first option implies that the driver unit of the drill bit is represented by downhole drilling motor, the second one utilizes sophisticated rotary steerable systems. Practical results of drilling wells with difficult profiles are presented. A quality assessment of drilling is provided through the example of comparing designed and actual trajectories, using different driver units for the drill bit, as well as properties of surrounding rocks, rheology of the drill fluid and other characteristics of dynamically active systems. A range of rotation speed has been determined that allows rotary steerable systems to have minimal oscillation amplitude of the bottom-hole assembly.   Analysis of investigation results showed that the main source of oscillations is linked to bending and compressing stresses, caused by well deviations as well as rigidity of the drilling tool. In effect, in the bottom-hole assembly occur auto-oscillations, making it impossible to correct azimuth and zenith angles. Alteration of rigidity in the bottom part of the tool and drilling parameters, implying reduced rotation speed of the drill string and regulation of drill bit pressure, can partially solve this problem, though increase in rotation speed is limited by technical characteristics of existing top drive systems.   

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M. V. Dvoinikov (2017) Research on technical and technological parameters of inclined drilling. Journal of Mining Institute. Vol 223. p. 86. DOI: 10.18454/pmi.2017.1.86
Oil and gas
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Modelling of fiberglass pipe destruction process

The article deals with important current issue of oil and gas industry of using tubes made of high-strength composite corrosion resistant materials. In order to improve operational safety of industrial pipes it is feasible to use composite fiberglass tubes. More than half of the accidents at oil and gas sites happen at oil gathering systems due to high corrosiveness of pumped fluid. To reduce number of accidents and improve environmental protection we need to solve the issue of industrial pipes durability. This problem could be solved by using composite materials from fiberglass, which have required physical and mechanical properties for oil pipes. The durability and strength can be monitored by a fiberglass winding method, number of layers in composite material and high corrosion-resistance properties of fiberglass. Usage of high-strength composite materials in oil production is economically feasible; fiberglass pipes production is cheaper than steel pipes. Fiberglass has small volume weight, which simplifies pipe transportation and installation. In order to identify the efficiency of using high-strength composite materials at oil production sites we conducted a research of their physical-mechanical properties and modelled fiber pipe destruction process.

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A. K. Nikolaev, Al'fredo Lazaro Koeio Velaskes (2017) Modelling of fiberglass pipe destruction process. Journal of Mining Institute. Vol 223. p. 93. DOI: 10.18454/pmi.2017.1.93
Geoecology and occupational health and safety
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Mathematical models of gas-dynamic and thermophysical processes in underground coal mining at different stages of mine development

New trends have been traced and the existing ones refined regarding filtration and diffusive motion of gases in coal beds and surrounding rock, spontaneous heating of coal and transport of gas traces by ventilation currents in operating coal mines. Mathematical models of gas-dynamic and thermophysical processes inside underworked territories after mine abandonment have been justified. Mathematical models are given for feasible air feeding of production and development areas, as well as for the development of geotechnical solutions to ensure gas-dynamic safety at every stage of coal mine operation. It is demonstrated that the use of high-performance equipment in the production and development areas requires more precise filtration equations used when assessing coal mine methane hazard. A mathematical model of pressure field of non-associated methane in the edge area of the coal seam has been justified. The model is based on one-dimensional hyperbolic equation and takes into consideration final rate of pressure distribution in the seam. Trends in gas exchange between mined-out spaces of high methane- and CO 2 -concentration mines with the earth surface have been refined in order to ensure environmental safety of underworked territories. 

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M. V. Gryazev, N. M. Kachurin, S. A. Vorob'ev (2017) Mathematical models of gas-dynamic and thermophysical processes in underground coal mining at different stages of mine development. Journal of Mining Institute. Vol 223. p. 99. DOI: 10.18454/pmi.2017.1.99
Geoecology and occupational health and safety
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Gas-dynamic processes affecting coal mine radon hazard

The paper focuses on vertical migration of radon in surrounding rocks described by Fick's first law as well as by the continuity equation for diffusion flow, with allowance for sorption and radioactive decay processes. Taking into account special characteristics of vertical radon diffusion, the process can be considered stable. It is demonstrated that for productive areas it is feasible to consider one-dimensional convective diffusion, as diffusive transport of radon by the air of productive areas occurs at steady-state conditions. Normally the factor of radon emissions prevails if atmospheric pressure is constant. Amount of air, calculated using this factor, by 20-30 % exceeds the one needed to dilute carbon dioxide to maximum allowed concentration (MAC). 

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V. I. Efimov, A. B. Zhabin, G. V. Stas' (2017) Gas-dynamic processes affecting coal mine radon hazard. Journal of Mining Institute. Vol 223. p. 109. DOI: 10.18454/pmi.2017.1.109
Geoecology and occupational health and safety
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Development of energy-saving technologies providing comfortable microclimate conditions for mining

The paper contains analysis of natural and technogenic factors influencing properties of mine atmosphere, defining level of mining safety and probability of emergencies. Main trends in development of energy-saving technologies providing comfortable microclimate conditions are highlighted. A complex of methods and mathematical models has been developed to carry out aerologic and thermophysical calculations. Main ways of improvement for existing calculation methods of stationary and non-stationary air distribution have been defined: use of ejection draught sources to organize recirculation ventilation; accounting of depression losses at working intersections; inertance impact of  air streams and mined-out spaces for modeling transitory emergency scenarios. Based on the calculation algorithm of airflow rate distribution in the mine network, processing method has been developed for the results of air-depressive surveys under conditions of data shortage. Processes of dust transfer have been modeled in view of its coagulation and settlement, as well as interaction with water drops in case of wet dust prevention. A method to calculate intensity of water evaporation and condensation has been suggested, which allows to forecast time, duration and quantity of precipitation and its migration inside the mine during winter season. Solving the problem of heat exchange between mine airflow and timbering of the ventilation shaft in a conjugation formulation permits to estimate depression value of natural draught and conditions of convective balance between air streams. Normalization of microclimatic parameters for mine atmosphere is forecasted for the use of heat-exchange units either heating or cooling and dehumidifying ventilation air. Algorithms are presented that permit to minimize ventilation energy demands at the stages of mine design and exploitation. 

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B. P. Kazakov, L. Yu. Levin, A. V. Shalimov, A. V. Zaitsev (2017) Development of energy-saving technologies providing comfortable microclimate conditions for mining. Journal of Mining Institute. Vol 223. p. 116. DOI: 10.18454/pmi.2017.1.116
Geoecology and occupational health and safety
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Justified selection of a seam degassing technology to ensure safety of intensive coal mining

The paper contains main aspects of methodological approach to objective analytic assessment of maximum permissible output of the mine faces from the viewpoint of gas factor. Analytic forecast is centered around the assessment of methane inflow into the face area from all possible sources, based on fundamental physical laws, modern tools of mathematical modeling and in-situ tests of main properties and state parameters of the gas-bearing coal formation. Objective and reliable estimation of permissible outputs is a starting point for justified selection of a seam degassing technology, that has to be based on time factor and predicted value of gas recovery from a coal seam to a degassing well. Recommendations have been formulated on the selection of degassing technology for the coal seam «Boldyrevsky» of the Kirov mine, based on the use of cutting-edge technological schemes (hydraulic fracture, carried out from development workings, etc.), successfully implemented on the mentioned site. 

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S. V. Slastunov, E. P. Yutyaev (2017) Justified selection of a seam degassing technology to ensure safety of intensive coal mining. Journal of Mining Institute. Vol 223. p. 125. DOI: 10.18454/pmi.2017.1.125
Geoeconomics and Management
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Principles of assessment and management approaches to innovation potential of coal industry enterprises

This paper examines problems related to forming a complex of indicators to assess innovation potential of an industrial enterprise, on the example of coal industry enterprises, and an integral indicator of innovation potential, used for comparative analysis of the state of affairs in the industry. Analysis of different approaches to defining the term «innovation potential» for industrial enterprises has been carried out; resource-based, resultative, integrative and capacitive approaches have been highlighted, the latter one based on assessment of enterprise capacities. A conclusion has been made regarding advantages of integrative approach. Research has been made on the role of industry in the fuel and power sector of China and dynamics of industry and enterprise development in Shanxi province. Basing on suggested approach a system of assessment principles has been formulated, taking into account specific features of coal industry enterprises. Complex of indicators to assess innovation potential has been developed using expert evaluation method. An expertise procedure is proposed to assess competence of experts; results obtained from the expertise are presented. Proposed complex of indicators includes 23 parameters combined into three groups. Testing of proposed complex of indicators has been carried out on the example of coal industry in Shanxi province (China). Application of all stated principles has been proved in the process of indicator selection, assessment and formulation of recommendations for subsequent innovation potential management of coal industry enterprises. Proposed approach to forming a complex of indicators of innovation potential for industry enterprises permits to link together the logic of innovation potential definition, formation of the system of its principles, selection of the indicators complex for assessment and subsequent innovation potential management of the enterprise.

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A. V. Kozlov, A. B. Teslya, Sya Chzhan (2017) Principles of assessment and management approaches to innovation potential of coal industry enterprises. Journal of Mining Institute. Vol 223. p. 131. DOI: 10.18454/pmi.2017.1.131
Geoeconomics and Management
  • Date submitted
    2017-03-01
  • Date published
    2017-02-26

Formation and development of theoretical principles for mineral resources logistics

Market transformations in Russia became foundations for formation and development of a new scientific and practical field in economics – logistics. Out of more than 30 existing definitions of logistics the authors according to their opinion have chosen the most appropriate. Logistics of mineral resources should be attributed to production (industrial) logistics. It is a proven fact that processes of supply chain management in mining industry and its infrastructure in the framework of mineral resources chain have some fundamental distinctions. Importance of material resources recycling in theory and practice of mineral resources logistics has been highlighted. Special features of merchandise assortment and classifications in the mining industry have been examined in conjunction with substantial contents of material flow. Special consideration has been given to relevant issues in the field of price formation for mining produce, in the view of specific relations between its costs and logistic procurement of the industry. Moreover, questions of inventory control in the mining industry, activity of commodity exchanges, management of mining logistics system have been addressed.

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B. K. Plotkin, M. M. Khaikin (2017) Formation and development of theoretical principles for mineral resources logistics. Journal of Mining Institute. Vol 223. p. 139. DOI: 10.18454/pmi.2017.1.139