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Puron L.D.R.,Higher Institute of Mining and Metallurgy, Moa | Puron L.D.R.,University of the State of Amazonas | Neto J.E.,Higher Institute of Mining and Metallurgy, Moa | Neto J.E.,University of the State of Amazonas | And 2 more authors.
2016 IEEE International Conference on Automatica, ICA-ACCA 2016 | Year: 2016

The presence of higher order harmonics causes problems in the quality and efficiency of energy supply by voltages sinusoidal inverters (VSI) to pulse-width-modulated (PWM) of the asynchronous motors drives, widely used in industry. This paper proposes an artificial neural network that identifies the quality of the sine wave and calculates the efficiency of electric drive system according to the index modulation of the sine wave voltage delivered to the electric motor, along with inverters modulated devices semiconductors (IGBTs). Also shown the effect on the efficiency of the operation of the harmonic losses. © 2016 IEEE.

Rodriguez J.B.,Autonomous University of Coahuila | Moreno J.B.,Higher Institute of Mining and Metallurgy, Moa | Infante A.R.,Higher Institute of Mining and Metallurgy, Moa
Geofisica Internacional | Year: 2012

New structural details of the Saramaguacán basin in central Cuba are presented, based on 3D inversion of gravimetric data constrained by wells and surface geology information. The basin shows complex tectonics of the overthrust process. A probable structural analysis of the basin suggests structures of ramp and shelf, as well as the location and geometry of the basin and several sub-basins. Known location and behavior of fault depth suggests some possible new or unknown faults. Geometry variation, depth and thickness were determined for different rock formations. This has great importance for the sedimentary (oil-bearing) and paleomargin (oil-source) rocks, because it is the basis for future research to select the best sites for drilling, as well as a broad estimate calculation of hydrocarbon volume that can be stored in the oil-collector rocks. Both groups of rocks are potential targets for oil prospecting. The oil-source rocks of the Cuban system were found to be around 4 km depth. They are associated with carbonated rocks of the Paleomargin. The oil-bearing rocks reache a depth of 10 km. The 3D model obtained supports the hypothesis that the ophiolites and the Cretaceous volcanic arc rocks were tectonically emplaced from south to north, on top of carbonate-terrigenous sequences from the Bahamas paleomargin. The model shows elements of the compressive tectonics that originated the Saramaguacán basin in the Mesozoic-Tertiary. It also suggests that the Saramaguacán basin presents favorable geologic conditions for oil deposits.

Rodriguez B.A.,Polytechnic University of Catalonia | Garcia G.G.,University of Oviedo | Coello-Velazquez A.L.,Higher Institute of Mining and Metallurgy, Moa | Menendez-Aguado J.M.,University of Oviedo
International Journal of Mineral Processing | Year: 2016

Bond standard procedures are often used in design of comminution circuits, especially in the case of ball mill grinding circuits. Although it is usually considered as an industry standard, its procedure was not fully defined by Fred Bond, and sometimes sensible variations in test results can be obtained due to some undefined steps in the method. This is the case of the calculation of characteristic size in product (P80), which must be calculated through interpolation using some PSD (particle size distribution) function and Bond's procedure did not establish the way to perform this calculation. The purpose of this technical note is to outline an evaluation of the adjustment quality of different distribution models in order to determine P80 in Bond's ball mill test. © 2016 Elsevier B.V.

Blanco-Quintero I.F.,University of Granada | Rojas-Agramonte Y.,University Mainz | Garcia-Casco A.,University of Granada | Garcia-Casco A.,Instituto Andaluz Of Ciencias Of La Tierra Csic Ugr | And 7 more authors.
Lithos | Year: 2011

High pressure igneous rocks (tonalites), generated by partial melting of subducted basaltic rocks accreted to the mantle wedge, are present in the La Corea serpentinite-matrix mélange (eastern Cuba) as centimeter- to meter-sized blocks and as concordant to crosscutting veins within high-pressure parent amphibolite blocks. The slab melts have adakitic signatures, in agreement with formation after partial melting of metabasite. Thermobarometric calculations indicate 620-680°C and 13-15kbar during crystallization of tonalites and down to 250-300°C, 6kbar during retrogression, indicating counter-clockwise P-T paths (hot subduction-cool exhumation). Free water required for melting of amphibolite at moderate temperature (700-750°C) and moderate pressure (13-16kbar) close to the wet basaltic solidus is inferred to have been provided after dehydration of sediments, altered basaltic crust and serpentinite of the subducting Proto-Caribbean lithosphere. Single zircon (SHRIMP) and phengite 40Ar/39Ar age data constrain the P-T-t evolution of the mélange from the timing of crystallization of melts at ~110-105Ma to cooling at ~87-84Ma, ca 350°C, ca 9kbar. These figures are consistent with subduction of an oblique ridge, shortly before 115Ma. Furthermore, our data indicate very slow exhumation (ca. 1mm/yr) in the subduction channel during the oceanic convergence stage (120-70Ma) until final fast exhumation to the surface occurred at 70-65Ma during a regional arc-platform collision event. © 2011 Elsevier B.V.

Rodriguez-Barcenas G.,Higher Institute of Mining and Metallurgy, Moa | Lopez-Huertas M.J.,University of Granada
Journal of the American Society for Information Science and Technology | Year: 2013

This research studied the role of knowledge organization in the process of decision making in the field of energy efficiency and rational use of energy (EERUE). Theoretical contributions to knowledge organization and decision making are stressed. We chose to work with a type of methodology known as multiple criteria decision making - Saaty's analytical hierarchies process (AHP). This made it possible to develop a detailed analysis of the decision-making process and arrive at a hierarchical model. The model provided a structure representing the studied field, where an order of priority could be given to the decision-making process. The knowledge derived may be used in other fields of study such as information retrieval and knowledge representation. © 2013 ASIS&T.

Gonzalez-Jimenez J.M.,Macquarie University | Proenza J.A.,University of Barcelona | Gervilla F.,University of Granada | Melgarejo J.C.,University of Barcelona | And 3 more authors.
Lithos | Year: 2011

Several chromitite bodies of variable sizes are hosted in dunite-harzburgite of the small (< 3. km) mining district of Sagua de Tánamo, in the Mayarí-Cristal ophiolitic massif, eastern of Cuba. The chromian spinel in these bodies displays a large range in Cr# (Cr/Cr + Al) atomic ratio from 0.74 to 0.45. In high-Cr chromitites, Cr# and Ti contents increase from harzburgite to dunite, to chromitite. A roughly opposite trend of variation in Cr# is observed in high-Al chromitites, although in this case Ti distributes randomly. The differences in the type of chromian spinel (i.e., high-Cr or high-Al) in the chromitite coincide with a different behavior of the platinum-group elements (PGE). Whereas high-Cr chromitites are rich in PGE and contain abundant grains of platinum-group minerals (PGM), high-Al chromitites are systematically poor in PGE and in PGM. The calculated melts in equilibrium with chromian spinel of high-Cr chromitite are island arc thoeliites (IAT) with boninitic affinity whereas those in equilibrium with chromian spinel of high-Al chromitites are back-arc basin basalts (BABB). The formation of high-Cr chromitites is interpreted as a result of the extensive reaction of harzburgite with migrating island arc tholeiite melts of boninitic affinity. Melt-rock reaction produces boninitic melts with variable composition and porous dunitic channels in which the mixing/mingling of melts promotes crystallization of mononomineralic high-Cr chromian spinel. In contrast, high-Al chromitites formed by the mixing/mingling of BABB melts within conduits not in equilibrium with dunite. Percolation of primitive BABB melts through pre-existing dunite dissolved olivine, producing melt conduits in which BABB melts mixed and formed high-Al chromian spinel. The higher PGE and PGM in high-Cr chromitites is not only a function of the degree of partial melting but is linked to interaction between the migrating melt and mantle harzburgite during the formation of the chromitite. The coexistence of both types of chromitites in one small mining district reflects the temporal and/or spatial variations of separate melt intrusions emplaced in different subarc mantle domains during the opening of a back-arc basin in a supra-subduction zone environment. © 2011 Elsevier B.V.

Cardenas-Parraga J.,University of Granada | Garcia-Casco A.,University of Granada | Garcia-Casco A.,Instituto Andaluz Of Ciencias Of La Tierra Csic Ugr | Nuez-Cambra K.,Institute Geologia y Paleontologia | And 4 more authors.
Boletin de la Sociedad Geologica Mexicana | Year: 2010

A new jadeitite jade locality has been discovered in the serpentinite-matrix subduction mélange of the Sierra del Convento (eastern Cuba) in a context associated with tectonic blocks of garnet-epidote amphibolite, tonalitic-trondhjemitic epidote gneiss and blueschist. The jade outcrops occur as blocks surrounded by serpentinite, as late Miocene-early Pliocene detritic sedimentary deposits formed during erosion of the mélange, and as Recent river and beach deposits related to the Macambo and Guardarraya rivers and their mouths. Jade from these outcrops show gem-quality varieties with colours ranging from greenish white to dark green. Potentially, the deposits may be easily exploited. Former exploitation (probably of the beach deposits) by the pre-Columbian Taino inhabitants of Cuba is documented by a large number of jade artifacts (mostly, petaloid axes) found in eastern Cuba.

Pozo A.C.,University of Information Sciences | Codorniu R.T.,Higher Institute of Mining and Metallurgy, Moa
Computacion y Sistemas | Year: 2015

In this paper we propose an online Wavelet Discrete Transform implementation scheme. Our proposal improves the execution time compared to the traditional sliding window method. Also, we modify the definition of the data window concept given in the original scheme. The experiments we performed show that the runtime cost of the proposed algorithm is better than that of the traditional sliding window method.

Martinez R.D.,Higher Institute of Mining and Metallurgy, Moa
Boletin de la Sociedad Geologica Mexicana | Year: 2010

The history of gold mining in Cuba has been described in numerous published works; however, it has not been systematized in accordance with the socio-economic developments of the island. Several classifications and conceptual models have been presented on the gold metallogeny in Cuba, but they are not clear and do not plainly reflect the essential attributes that characterize gold mineralization on the island. The aforementioned circumstances justified a historical-descriptive research project based on an exhaustive literature review, and the analysis and interpretation of the available information. Gold mining on the island extends over three historical stages: colonial, neocolonial and revolutionary. Four main metallogenetic episodes for gold formation can be distinguished on the island of Cuba: (i) an Aptian-Campanian stage of mineralization with low- and high-sulfidation Au-Cu porphyries, Au skarns and Au-Ag epithermal deposits; (ii) a late Campanian-early Danian episode that hosts orogenic-type gold mineralization and listvenites; (iii) very prolific Danian-middle Eocene gold mineralization in listvenites in Central Cuba and in Palaeogene volcanic island arc rocks in the southern part of eastern Cuba; and lastly, (iv) an Oligocene-Recent mineralization stage in which surface gossans are produced by the oxidation of sulfide ores and placers. The future of gold mining in Cuba is very attractive, but at a small to medium scale.

The hotel exploitation, while continuing to satisfy the customers, needs to decrease the requests of electric power as the principal energy carrier. Solving issues regarding the occupation of a hotel integrally, taking the air conditioning as center of attention, which demands the bigger consumptions of electricity, results in a complex task. To solve this issue, a procedure was implemented to optimize the operation of the water-chilled systems. The procedure integrates an energy model with a strategy of low occupation following energetic criteria based on combinatorial-evolutionary criteria. To classify the information, the formulation of the tasks and the synthesis of the solutions, a methodology of analysis and synthesis of engineering is used. The energetic model considers the variability of the local climatology and the occupation of the selected rooms, and includes: the thermal model of the building obtained by means of artificial neural networks, the hydraulic model and the model of the compression work. These elements allow to find the variable of decision occupation, performing intermediate calculations to obtain the velocity of rotation in the centrifugal pump and the output temperature of the cooler water, minimizing the requirements of electric power in the water-chilled systems. To evaluate the states of the system, a combinatorial optimization is used through the following methods: simple exhaustive, stepped exhaustive or genetic algorithm depending on the quantity of variants of occupation. All calculation tasks and algorithms of the procedure were automated through a computer application. © IBERAMIA and the authors.

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