977 resultados para Circuit of rock platense


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No país existem inúmeras estruturas e obras civis que estão em operação a dezenas de anos e necessitam de monitoramento periódico devido a sua importância. Por este motivo, a dissertação apresenta um caso de um túnel antigo com problema de queda de bloco e visa instigar novas pesquisas e aumentar o conhecimento sobre o tema. Foram realizadas inspeções em campo em alguns túneis não revestidos da Estrada de Ferro Vitória-Minas (EFVM), bem como os ensaios em laboratório e in situ realizados nas amostras e no maciço rochoso para caracterizar o problema. Para o estudo foi escolhido o túnel Monte Seco Linha 1 e Linha 2 nos quais foram realizadas sondagens rotativas inclinadas e orientadas próximas ao eixo para investigação dos planos de descontinuidade. Os conceitos da Teoria dos Blocos-Chave foram aplicados às famílias de descontinuidades encontradas nos Túneis Monte Seco L1 e L2 para identificar os possíveis blocos instáveis formados pelas escavações. Para obtenção dos parâmetros geotécnicos de resistência e deformabilidade foram realizados ensaios de compressão uniaxial instrumentados com strain gages. A resistência a tração foi obtida através de Ensaio de Compressão Diametral (ECD). No ensaio de campo foi utilizado o Martelo de Schmidt para avaliação da rocha in situ. Através da análise dos dados foi possível distinguir setores cuja ocorrência de queda de blocos são maiores e a classe do maciço rochoso de acordo com a proposta de Bieniawski.

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El Slope Mass Rating (SMR, Romana, 1985) constituye una clasificación geomecánica de uso muy extendido para la caracterización de taludes en roca. Se obtiene por adición al índice RMR básico, calculado a partir de valores característicos del macizo rocoso, de una serie de factores de corrección dependientes del paralelismo discontinuidad-talud, del buzamiento de las discontinuidades, del buzamiento relativo entre las discontinuidades y el talud, así como del método de excavación empleado. En este trabajo se propone un método gráfico que permite obtener los parámetros de corrección del SMR (F1, F2 y F3) representando en proyección estereográfica los planos de discontinuidad y del talud a estudiar.

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Datasets and results of the paper: Characterization of rock slopes through slope mass rating using 3D point clouds, Riquelme et al 2016, IJRMMS.

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Far-field stresses are those present in a volume of rock prior to excavations being created. Estimates of the orientation and magnitude of far-field stresses, often used in mine design, are generally obtained by single-point measurements of stress, or large-scale, regional trends. Point measurements can be a poor representation of far-field stresses as a result of excavation-induced stresses and geological structures. For these reasons, far-field stress estimates can be associated with high levels of uncertainty. The purpose of this thesis is to investigate the practical feasibility, applications, and limitations of calibrating far-field stress estimates through tunnel deformation measurements captured using LiDAR imaging. A method that estimates the orientation and magnitude of excavation-induced principal stress changes through back-analysis of deformation measurements from LiDAR imaged tunnels was developed and tested using synthetic data. If excavation-induced stress change orientations and magnitudes can be accurately estimated, they can be used in the calibration of far-field stress input to numerical models. LiDAR point clouds have been proven to have a number of underground applications, thus it is desired to explore their use in numerical model calibration. The back-analysis method is founded on the superposition of stresses and requires a two-dimensional numerical model of the deforming tunnel. Principal stress changes of known orientation and magnitude are applied to the model to create calibration curves. Estimation can then be performed by minimizing squared differences between the measured tunnel and sets of calibration curve deformations. In addition to the back-analysis estimation method, a procedure consisting of previously existing techniques to measure tunnel deformation using LiDAR imaging was documented. Under ideal conditions, the back-analysis method estimated principal stress change orientations within ±5° and magnitudes within ±2 MPa. Results were comparable for four different tunnel profile shapes. Preliminary testing using plastic deformation, a rough tunnel profile, and profile occlusions suggests that the method can work under more realistic conditions. The results from this thesis set the groundwork for the continued development of a new, inexpensive, and efficient far-field stress estimate calibration method.

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This survey of European industrial policy aims to set out and explain the great significance of European integration in determining (changes in) structure and performance of industry in the EU. This influence is explored from the policy side by analysing the transformation of the framework within which both EU and Member States' industrial policy can be pursued. Empirical economic analysis is not included because this BEEP Briefing was originally written for a handbook3 in which other authors were assigned a range of industrial economics subjects. In the last 25 years or so, the transformation is such that the nature and scope of industrial policy at both levels of government has profoundly changed as well. Indeed, the toolkit of measures has shrunk considerably, disciplines have been tightened and the economic policy views behind industrial policy have altered everywhere. The pro-competitive logic of deeper market integration itself is rarely questioned nowadays and industrial policy at the two levels takes on different forms. The survey discusses at some length the division of powers between, and the complementarity of, the Member States' and EU levels of government when it comes to industrial policy, based on a fairly detailed classification of industrial policy instruments. The three building blocks of the wide concept of industrial policy as defined in this BEEP Briefing consist of the EU framework of market integration, EU horizontal industrial policy and its EU sectoral or specific counterpart. Each one is surveyed at the EU level. Preceding these three sections is a discussion of three cross-cutting issues, namely, the indiscriminate use of the 'competitiveness' label in the EU circuit of business and policy makers, the relation between services and EU industrial policy and, finally, that of European infrastructure. One major conclusion is that, today, the incentive structure for industry and industrial markets is dominated by the stringency of the overall EU framework and to some moderate degree by the horizontal approach.

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The achievement of deep penetration (562 m) of seafloor basalts at Hole 504B, near the Costa Rica Rift (1°13.63'N, 83°43.81'W), on DSDP Legs 69 and 70 presented a rare opportunity to examine the structure of young (6 m.y.) oceanic crust. In addition to the recovery of samples for laboratory studies, an extensive suite of downhole logs and experiments was carried out at this site, for two main purposes: (1) to allow reliable deductions about the nature of the entire section of penetrated crust, because recovery of samples was far from complete (-25%); (2) to probe the physical state of rock around the drilled hole on a scale of tens of meters to kilometers. Information on the latter large-scale phenomena at Hole 504B were provided mainly by the oblique seismic experiment, utilizing a bore-hole seismometer (Stephen 1983), and by the large-scale-electrical- resistivity experiment described below.

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A large number of samples of nonlithified and lithified sediments from Leg 93 sites were analyzed for their contents of organic carbon and calcium carbonate. An average of two samples was selected from every core for carbonate determination; organic carbon was measured in most of these samples. Nearly all of these analyses were performed on board Glomar Challenger for samples from Sites 603 and 604. Site 605 samples, plus some of the deeper samples from Hole 603B, were analyzed at the University of Michigan. The procedures used in both cases were virtually the same, and their results compared well. Organic carbon analyses were done using a Hewlett- Packard 185-B CHN Analyzer. Portions of samples selected for calcium carbonate determinations were treated with dilute HC1 to remove carbonate, washed with deionized water, and dried at 110°C. A Cahn Electrobalance was used to weight 20-mg samples of sediment for CHN analysis. Samples were combusted at 1050°C in the presence of an oxidant, and the volumes of the evolved gases determined as measures of the C, H, and N contents of sediment organic matter. Areas of gas peaks were determined and compared to those of rock standards of known carbon and nitrogen contents. These values were used to standardize instrument response so that C/N atomic ratios could be reported. Organic carbon concentrations were calculated on the basis of sediment dry weight. Hydrogen elemental analysis with the procedure used is untrustworthy because of the variable amounts of clay minerals and their hydrates, hence hydrogen values are not reported for samples analyzed by this method.

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v. 1. The circuit of Ireland, by Muircheartach Mac Neill, prince of Aileach / by Cormacan Eigeas; with a translation and notes by John O'Donovan. A brief description of Ireland: 1590 / edited by Aquilla Smith -- v. 2. A treatice of Ireland / by John Dymmok; with notes by Richard Butler. Annales de Monte Fernandi (Annals of Multifernan) / edited by Aquilla Smith. A statute of the fortieth year of King Edward III, enacted in a Parliament held in Kilkenny, A.D. 1367 / with a translation and notes by James Hardiman.

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CONTENTS: 1. An act to create a Bureau of Highways, and prescribe its duties and powers, and to make an appropriation for its expenses. [Approved March 27, 1895.]--2. An act providing for the erection and operation of rock-crushing plants at the state prisons, for the preparation of highway material for the benefit of the people of the state, and providing for the necessary advances and appropriation of money to carry out said work. [Approved March 28, 1895.]--3. Physical features of the state, by Marsden Manson.--4. The effect of roads upon industrial development, by R.C. Irvine.--5. Proposed highway legislation, with comments and resolutions thereon

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The aim of this study has been to revaluate Bronze Age society using rock art as an archaeological material. It has also sought to question certain prevailing interpretative trends within the research of rock art; ascribing it as ritual practices, expression of a social elite and the adoption of symbols from cultures along the Mediterranean Sea. This has chiefly been made possible through the application of Slavoj Žižeks ideas about the ideological fantasy and the sublime object of ideology. The thesis proposes a connection between art and ideology. A selected sampling of rock carvings from three areas in Sweden has been made in order to further investigate the relationship between different figurative motives both at a regional level, as well as a local. This study claims that rather than having been under the control of an elite, rock art has been accessible for the majority of the population both to produce and view. The depiction of human representation as rock carving does not depict a clear social stratification. It is also argued that the idea of images displayed on the rocks having roots in the imagery of Mediterranean civilizations is a construct of current western ideology, as the symbolic connection between the cultures is tenable at best, according to this study. 

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We theoretically study thermal transport in an electronic interferometer comprising a parallel circuit of two quantum dots, each of which has a tunable single electronic state which are connected to two leads at different temperature. As a result of quantum interference, the heat current through one of the dots is in the opposite direction to the temperature gradient. An excess heat current flows through the other dot. Although locally, heat flows from cold to hot, globally the second law of thermodynamics is not violated because the entropy current associated with heat transfer through the whole device is still positive. The temperature gradient also induces a circulating electrical current, which makes the interferometer magnetically polarized.

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The patterns of rock comminution within tumbling mills, as well as the nature of forces, are of significant practical importance. Discrete element modelling (DEM) has been used to analyse the pattern of specific energy applied to rock, in terms of spatial distribution within a pilot AG/SAG mill. We also analysed in some detail the nature of the forces, which may result in rock comminution. In order to examine the distribution of energy applied within the mill, the DEM models were compared with measured particle mass losses, in small scale AG and SAG mill experiments. The intensity of contact stresses was estimated using the Hertz theory of elastic contacts. The results indicate that in the case of the AG mill, the highest intensity stresses and strains are likely to occur deep within the charge, and close to the base. This effect is probably more pronounced for large AG mills. In the SAG mill case, the impacts of the steel balls on the surface of the charge are likely to be the most potent. In both cases, the spatial pattern of medium-to-high energy collisions is affected by the rotational speed of the mill. Based on an assumed damage threshold for rock, in terms of specific energy introduced per single collision, the spatial pattern of productive collisions within each charge was estimated and compared with rates of mass loss. We also investigated the nature of the comminution process within AG vs. SAG mill, in order to explain the observed differences in energy utilisation efficiency, between two types of milling. All experiments were performed using a laboratory scale mill of 1.19 m diameter and 0.31 m length, equipped with 14 square section lifters of height 40 mm. (C) 2006 Elsevier Ltd. All rights reserved.

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Através de pesquisas bibliográficas, entrevistas e do procedimento de observaçãoparticipante, a dissertação realiza uma análise da ocorrência de hábitos e costumes genuinamente caiçaras nas comunidades situadas no Saco do Mamanguá e na Ilha do Araújo - em Paraty - e o processo de hibridação cultural identificado nas comunidades em questão, em decorrência do turismo cultural ocasionado pela realização de eventos - mais especificamente, da Festa Literária Internacional de 'Parati' e do Circuito Paralelo de Idéias. Mostra como as comunidades aparecem representadas em tais eventos e discorre sobre a importância dada à participação em eventos tidos como culturais pela sociedade atual. Além disso, traça um diagnóstico das reais interferências ocasionadas na cultura caiçara através da atividade turística - viável aos interesses de manutenção e difusão de tal cultura - e que, por sua vez, é responsável por 80% do sistema econômico local.

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Lichens are symbiotic organisms that often dominate stressful environments such as the surfaces of rock and tree bark. Whether or not competition occurs between lichens in these environments, however, is controversial. This review considers various aspects of the competitive interactions between lichens including the observational studies that suggest competitive effects may be important, the methods that have been used to study lichen competition in the field, the result of marginal contacts between lichen thalli, the attributes that may give a species a competitive advantage, and the role of competition in structuring lichen communities. These studies suggest that competition for space and light does occur in lichen communities and that individual lichen species can be excluded from a substratum as a result of competition. Moreover, competitive interactions in multi-species communities can also lead to stable assemblages of species. Future research should consider those aspects of the lichen symbiosis that may confer a competitive advantage and the factors that may promote stability in multi-species communities. Studies of competition in lichen communities may have implications for other stressful environments in which symbiotic organisms play a significant role. ©2007 Balaban.