164 research outputs found

    Depositional style and tectonostratigraphic evolution of El Bierzo Tertiary sub-basin (Pyrenean orogen, NW Spain)

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    El Bierzo Tertiary sub-basin (Oligocene-Miocene, NW Spain) is a small remnant of the western Duero Basin, a nonmarine broken foreland basin developed in front of the Cantabrian Mountains (Pyrenean orogen). The alluvial infill of El Bierzo Tertiary sub-basin consists of a coarsening-upward succession from fluvial (Toral Formation) to alluvial-fan deposits (Las Médulas Formation) and reflects the uplift of the Cantabrian Mountains, in the north, and then of the related Galaico-Leoneses Mountains, in the south. These alluvial deposits show signs of having been laid down mainly by catastrophic flows (flood-dominated systems) and consist of three main depositional elements, namely, flood-plain fines, and lobe and channel conglomerates and sandstones. The vertical stacking patterns of these deposits and their relationships to the Alpine structures permit to unravel the tectonosedimentary evolution of the basin. The alluvial-plain element is the main constituent of a wide unconfined alluvial plain (Toral Formation) during the early stages of basin evolution, whereas the channel and lobe elements form a set of relatively small, laterally confined alluvial fans (Las Médulas Formation) fed first from the north and then from the south. Las Médulas deposits form two superposed units, the lower unit, cut by the Alpine thrusts, shows a progradational character, and the upper unit, which postdates most of the thrusts but not the youngest ones, displays a composite retrogradational trend. This organisation reflects the interplay between thrust emplacement and alluvial-fan sedimentation and suggests that maximum progradation took place during the climax of Alpine deformation

    Depositional style and tectonostratigraphic evolution of El Bierzo Tertiary sub-basin (Pyrenean orogen, NW Spain)

    Get PDF
    El Bierzo Tertiary sub-basin (Oligocene-Miocene, NW Spain) is a small remnant of the western Duero Basin, a nonmarine broken foreland basin developed in front of the Cantabrian Mountains (Pyrenean orogen). The alluvial infill of El Bierzo Tertiary sub-basin consists of a coarsening-upward succession from fluvial (Toral Formation) to alluvial-fan deposits (Las Médulas Formation) and reflects the uplift of the Cantabrian Mountains, in the north, and then of the related Galaico-Leoneses Mountains, in the south. These alluvial deposits show signs of having been laid down mainly by catastrophic flows (flood-dominated systems) and consist of three main depositional elements, namely, flood-plain fines, and lobe and channel conglomerates and sandstones. The vertical stacking patterns of these deposits and their relationships to the Alpine structures permit to unravel the tectonosedimentary evolution of the basin. The alluvial-plain element is the main constituent of a wide unconfined alluvial plain (Toral Formation) during the early stages of basin evolution, whereas the channel and lobe elements form a set of relatively small, laterally confined alluvial fans (Las Médulas Formation) fed first from the north and then from the south. Las Médulas deposits form two superposed units, the lower unit, cut by the Alpine thrusts, shows a progradational character, and the upper unit, which postdates most of the thrusts but not the youngest ones, displays a composite retrogradational trend. This organisation reflects the interplay between thrust emplacement and alluvial-fan sedimentation and suggests that maximum progradation took place during the climax of Alpine deformation

    About Attitudes and Perceptions: Finding the Proper Way to Consider Latent Variables in Discrete Choice Models

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    We provide an in-depth theoretical discussion about the differences between attitudes and perceptions, as well as an empirical exercise to analyze its effects. This discussion is of importance, as the large majority of papers considering attitudinal latent variables, just consider those as attributes affecting directly the utility of a certain alternative while systematic taste variations are rarely taken into account and perceptions are normally completely ignored. The results of our case study show that perceptions may indeed affect the decision making process and that they are able to capture a significant part of the variability that is normally explained by alternative specific constants. In the same line, our results indicate that attitudes may be a reason for systematic taste variations, and that a proper categorization of the latent variables, in accordance with the underlying theory, may outperform the customary assumption of linearity

    Model-Free Predictive Current Control of a Voltage Source Inverter

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    Indexación: Scopus.Conventional model predictive control (MPC) of power converter has been widely applied to power inverters achieving high performance, fast dynamic response, and accurate transient control of power converter. However, the MPC strategy is highly reliant on the accuracy of the inverter model used for the controlled system. Consequently, a parameter or model mismatch between the plant and the controller leads to a sub-optimal performance of MPC. In this paper, a new strategy called model-free predictive control (MF-PC) is proposed to improve such problems. The presented approach is based on a recursive least squares algorithm to identify the parameters of an auto-regressive with exogenous input (ARX) model. The proposed method provides an accurate prediction of the controlled variables without requiring detailed knowledge of the physical system. This new approach and is realized by employing a novel state space identification algorithm into the predictive control structure. The performance of the proposed model-free predictive control method is compared with conventional MPC. The simulation and experimental results show that the proposed method is totally robust against parameters and model changes compared with the conventional model based solutions.https://ieeexplore.ieee.org/document/926284

    Analyzing the Continuity of Attitudinal and Perceptional Indicators in Hybrid Choice Models

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    This paper addresses the continuity of attitudinal and perceptual indicators in hybrid discrete choice models and the main objective of this work is to compare the consequences of treating the indicators as continuous or ordinal outcomes, given different assumptions about the way in which these are stated. Based on tradition and for computational reasons, such indicators are predominantly treated as continuous outcomes. This usually neglects their nature (as respondents are normally asked to state their preferences, or level of agreement with a set of statements, using a discrete scale) and may induce important bias. We conducted an analysis based on simulated data and real data (two case studies) and were able to find that the distribution of the indicators (especially when associated with non-uniformly spaced thresholds) may lead to a clear deterioration of the model's predictive capacity, especially when assuming continuous indicators. Along the same line, higher relative variability among the latent variables increases the differences between both approaches (ordinal and continuous outcomes), especially concerning goodness-offit of the discrete-choice component. It was not possible to identify a relation between the predictive capacity of both approaches and the amount of available information. Finally, both case studies using real data show an improvement in overall goodness-of-fit when considering the indicators as ordinal outcomes, but this does not translate in a better predictability of the discrete choices

    Endocrine Disruptor Impacts on Fish From Chile: The Influence of Wastewaters

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    Indexación ScopusIndustrial wastewaters and urban discharges contain complex mixtures of chemicals capable of impacting reproductive performance in freshwater fish, called endocrine-disrupting compounds (EDCs). In Chile, the issue was highlighted by our group beginning over 15 years ago, by analyzing the impacts of pulp and paper mill effluents (PPME) in the Biobio, Itata, and Cruces River basins. All of the rivers studied are important freshwater ecosystems located in the Mediterranean region of Central Chile, each with a unique fish biodiversity. Sequentially, we developed a strategy based on laboratory assays, semicontrolled-field experiments (e.g., caging) and wild fish population assessments to explore the issue of reproductive impacts on both introduced and native fish in Chile. The integration of watershed, field, and laboratory studies was effective at understanding the endocrine responses in Chilean freshwater systems. The studies demonstrated that regardless of the type of treatment, pulp mill effluents can contain compounds capable of impacting endocrine systems. Urban wastewater treatment plant effluents (WWTP) were also investigated using the same integrated strategy. Although not directly compared, PPME and WWTP effluent seem to cause similar estrogenic effects in fish after waterborne exposure, with differing intensities. This body of work underscores the urgent need for further studies on the basic biology of Chilean native fish species, and an improved understanding on reproductive development and variability across Chilean ecosystems. The lack of knowledge of the ontogeny of Chilean fish, especially maturation and sexual development, with an emphasis on associated habitats and landscapes, are impediment factors for their conservation and protection against the threat of EDCs. The assessment of effects on native species in the receiving environment is critical for supporting and designing protective regulations and remediation strategies, and for conserving the unique Chilean fish biodiversity. © Copyright © 2021 Barra, Chiang, Saavedra, Orrego, Servos, Hewitt, McMaster, Bahamonde, Tucca and Munkittrick.https://www.frontiersin.org/articles/10.3389/fendo.2021.611281/ful

    The contribution of Real Madrid’s first five European Cups to the emergence of a common football space

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    Real Madrid won the first five editions of the European Champion Clubs’ Cup (now formally known as the UEFA Champions League, and to which we will refer hereon as the European Cup) between 1956 and 1960, contributing decisively to the competition’s consolidation. The tournament’s history started towards the end of 1954, when a journalist of the French sports daily L’Équipe, Gabriel Hanot, published an article arguing the need to organise a competition that could bring together the champions of every European league. However, this was not an original proposal. Thirty years before Hanot’s article proposals for such a football competition were circulated among the game’s ruling elite. Unfortunately, at that time the lack of a good transport infrastructure to travel through Europe discouraged the proposers which, instead, turned their attention to regional supranational competitions, such as the Mitropa Cup or the Latin Cup. The first five editions of the European Cup witnessed as many victories of Real Madrid, thus forging an indissoluble bond between the competition and the Spanish club. These five European titles did not only cement the supremacy of Real Madrid on the pitch as a great football team, but they also contributed to the consolidation of the European Cup itself in the public’s imaginary. We also argue that given the expectations raised by Real Madrid’s triumphs across Europe those matches might have contributed as well to the emergence of a European football space. Since 1955 Real Madrid occupied an ever increasing space in the press across Europe. Real Madrid was then considered as the best expression of modernity in football. This chapter aims to analyse the meaning of these five European Cup titles for the emergence and definition of a nascent European football space. We, of course, also question whether such a common space can be found. The chapter explores in depth the reasons behind Real Madrid’s enthusiasm with the new European competition. We also examine the social impact that Real Madrid’s hegemony in the European Cup had in the context of Spain’s international isolation during General Franco’s dictatorship (1939-1975). In order to achieve the above mentioned objectives, the chapter relies on thematic analysis of selected publications in the Spanish and British press during those years. Moreover, we have also relied on a review of academic literature on the role of Real Madrid during the Franco dictatorship years, mainly the 1950s and 60s. This chapter is part of wider on-going research. In this research we examine the content of two Spanish dailies (ABC and Marca) and three British newspapers (The Guardian, The Times and the Daily Mirror). We searched these newspapers for content related to Real Madrid on specific dates: The semifinal games (two legs) and the final of each one of the five years where Real Madrid won the European Cup. We searched for content the day of each match, the day before and two days after each one of the matches. This chapter is a presentation of the findings obtained through thematic analysis of the data obtained through those searches

    The Potential of Electromobility in Austria: An Analysis Based on Hybrid Choice Models

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    This paper analyses the impact of the introduction of electromobility in Austria, focusing specifically on the potential demand for electric vehicles in the automotive market. We estimate discrete choice behavioral mixture models considering latent variables; these allows us to deal with this potential demand as well as to analyze the effect of different attributes of the alternatives over the potential market penetration. We find out that some usual assumptions regarding electromobilityalso hold for the Austrian market (e.g. proclivity of green-minded people and reluctance of older individuals), while others are only partially valid (e.g. the power of the engine is not relevant for purely electric vehicles). Along the same line, it was possible to establish that some policy incentives would have a positive effect over the demand for electrical cars, while others - such as an annual Park and Ride subscription or a one-year-ticket for public transportation - would not increase thewillingness-to-pay for electromobility. Our work suggests the existence of reliability thresholds, concerning the availability of charging stations. Finally this paper enunciates and successfully tests an alternative approach to address unreported information regarding income in presence of endogeneity and multiple information sources

    Validation of energy deposition simulations for proton and heavy ion losses in the CERN Large Hadron Collider

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    Monte Carlo shower simulations are essential for understanding and predicting the consequences of beam losses in high-energy proton and ion colliders. Shower simulations are routinely used at CERN for estimating the beam-induced energy deposition, radiation damage, and radioactivity in the Large Hadron Collider (LHC). Comparing these shower simulations against beam loss measurements is an important prerequisite for assessing the predictive ability of model calculations. This paper validates fluka simulation predictions of beam loss monitor (BLM) signals against BLM measurements from proton fills at 3.5 and 4 TeV and 208^{208}Pb82+^{82+} ion fills at 1.38A  TeV. The paper addresses typical loss scenarios and loss mechanisms encountered in LHC operation, including proton collisions with dust particles liberated into the beams, halo impact on collimators in the betatron cleaning insertion, proton-proton collisions in the interaction points, and dispersive losses due to bound-free pair production in heavy ion collisions. Model predictions and measured signals generally match within a few tens of percent, although systematic differences were found to be as high as a factor of 3 for some regions and source terms
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