Underground System
Mostrando 1-12 de 70 artigos, teses e dissertações.
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1. Unplanned dilution back analysis in an underground mine using numerical models
Abstract In underground mines, stability problems can cause unplanned dilution, increasing the costs of mining operations, such as loading, transport, crushing and grinding. This is usually dealt with by simply increasing investments with support. However, the design geometry of stopes and drifts also has a great effect on a stope’s stability. The use of e
REM - International Engineering Journal. Publicado em: 2022
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2. Strategies used to control the costs of underground ventilation in some Brazilian mines
Abstract In an underground mine, the ventilation is responsible for 25% to 50% of its electrical energy consumption. In countries such as South Africa, United States and Canada researchers have started to achieve a significant reduction in energy consumption without neglecting aspects of the quantity and quality of air required for the best performance of th
REM, Int. Eng. J.. Publicado em: 2020-12
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3. Technical Losses Reduction in Underground Reticulated Distribution Systems using Artificial Neural Networks and Smart Grid Features
ABSTRACT This work presents the methodology, development and testing of an autonomous system, based on Artificial Neural Networks (ANN), for the reduction of technical losses in reticulated underground systems through the optimal control of the capacitor banks (CBs) present in the grid. The proposed methodology includes Smart Grid features, including practic
Braz. arch. biol. technol.. Publicado em: 22/10/2018
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4. Thermal profiles in pervious concrete during summer rain simulations
ABSTRACT Pervious concrete pavement systems may have many environmental benefits including the mitigation of heat island impacts. This mitigation is a complex combination of pervious concrete’s insulating capability and its ability to store water which may provide evaporative cooling. However, the introduction of water may also bring heat into the system,
Matéria (Rio J.). Publicado em: 18/10/2018
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5. Degradación de un efluente textil real asistida por Fe/PVA y materiales residuales magnéticos
ABSTRACT Organic compounds present on industrial wastes are mostly resistant to conventional biological and chemical treatments. Textile industry has presented several environmental problems mainly related to the use and management of water resources. It has a high consumption of potable and underground water in its processes. These wastewaters are one of th
Matéria (Rio J.). Publicado em: 19/07/2018
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6. Temperature and circadian effects on metabolic rate of South American echimyid rodents, Trinomys setosus and Clyomys bishopi (Rodentia: Echimyidae)
ABSTRACT Basal metabolic rate (BMR) represents the lowest level of metabolic activity capable to sustain homeostasis in an endotherm and is an important tool to compare metabolic rates of different species. Echimyidae is the most specious family within caviomorph rodents, however, little is known about the biology of its species, such as Trinomys setosus (De
Zoologia (Curitiba). Publicado em: 26/04/2018
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7. New concept of tunnel boring machine: high performance using water jet and diamond wire as rock cutting technology
Abstract Tunnel boring machines are important tools in underground infrastructure projects. Although being well established equipment, these machinesare based on designsof more than 60 years ago and are characterized by big dimensions, enormous weight and high power consumption. Commercial aspects should be noted too. The model adopted by the TBM industry re
REM, Int. Eng. J.. Publicado em: 2018-03
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8. Structural features of species of Asteraceae that arouse discussions about adaptation to seasonally dry environments of the Neotropics
ABSTRACT Seasonally-dry environments of the Neotropics, such as the South American Chaco, exert selective pressures on vegetation through a pronounced water deficit. We describe the underground system and leaf anatomy of three species of Asteraceae from the Brazilian portion of the Chaco (Pterocaulon purpurascens Malme, Wedelia trichostephia DC., and Pectis
Acta Bot. Bras.. Publicado em: 27/11/2017
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9. Fructan dynamics in the underground organs of Chresta exsucca (Asteraceae), a dry season flowering species
ABSTRACT Climatic seasonality has an influence on the phenology of native Cerrado plants. Herbs and subshrubs tend to flower in the rainy season, although some species of these habits flower in the dry season. Reserve carbohydrates, stored in the underground organs, are used to support phases of high energy-demand, but also may protect plants from damage dur
Acta Bot. Bras.. Publicado em: 06/11/2017
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10. Risk analysis and reliability of the GERDA Experiment extraction and ventilation plant at Gran Sasso mountain underground laboratory of Italian National Institute for Nuclear Physics
Abstract The aim of this study is the risk analysis evaluation about argon release from the GERDA experiment in the Gran Sasso underground National Laboratories (LNGS) of the Italian National Institute for Nuclear Physics (INFN). The GERDA apparatus, located in Hall A of the LNGS, is a facility with germanium detectors located in a wide tank filled with abou
REM, Int. Eng. J.. Publicado em: 2017-09
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11. Design of Ground Penetrating Radar Antenna for Detecting Soil Contamination at L-band Frequencies
Abstract Maintenance of oil pipelines is an issue of great concern for oil companies. Soil contamination is caused by oil leaks from underground pipelines. Ground penetrating radar (GPR) is a rapid and relatively inexpensive technique used for locating and characterizing soil contaminated sites without producing fractures and causing further migration of con
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-09
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12. AC Induced Corrosion of Underground Steel Pipelines. Faradaic Rectification under Cathodic Protection: II. Theoretical Approach with Electrolyte Resistance and Double Layer Capacitance for Bi-Tafelian Corrosion Mechanism
AC corrosion enhancement of buried steel pipe is induced by high stray AC electromagnetic field and to the faradaic rectification due to non-linearity of current-potential characteristics. In Part I, this phenomenon was evaluated by neglecting the electrical resistance of soil electrolyte. In this part, we will examine when this resistance is no longer negli
J. Braz. Chem. Soc.. Publicado em: 2016-03