217 research outputs found

    Reconstruction of Marine Fisheries Catches for the Republic of Malta (1950-2010)

    Get PDF
     The marine fisheries catches of Malta were reconstructed for the period 1950-2014, including for reported and previously unreported commercial large- and small-scale catches, unmonitored fisheries catches, i.e., subsistence and recreational fisheries, as well as major discards. The present study updates and improves a previous catch reconstruction for Malta for the 1950-2010 time period. Reconstructed marine fisheries catches for Malta are nearly 1.3 times the official landings reported by the FAO and national authorities on behalf of Malta, increasing from around 1,200 t·year-1 in the 1950s to 3,700 t·year-1 in the 2010s. The discrepancy between reported and reconstructed total catches is mostly due to the subsistence catches estimated, which here consist exclusively of on-board consumption and take-home catch of commercial fishers. While the Maltese fisheries statistical system includes procedures to estimate ‘unmonitored’ commercial landings, this contribution documents that it would be beneficial to also account for non-commercial catches

    Robusno neizrazito prilagođavanje pojačanja RST regulatora za WECS dvostruko napajani asinkroni generator

    Get PDF
    This paper proposes a new robust fuzzy gain scheduling of RST controller for a Wind Energy Conversion System (WECS) based on a doubly fed induction generator (DFIG). First, a designed fuzzy gain scheduling of RST controller is investigated, in which fuzzy rules are utilized on-line to adapt the RST controller parameters based on the error and its first time derivative. The aim of the work is to apply and compare the dynamic performances of two types of controllers (namely, Polynomial RST and Fuzzy-RST) for the WECS. A vector control with stator flux orientation of the DFIG is also presented in order to achieve control of active and reactive power of the wind turbine transmitted to the grid and to make the wind turbine adaptable to different constraints. The results obtained by simulation prove the effectiveness of the proposed controller in terms of decoupling, robustness and dynamic performance for different operating conditions.U radu je predloženo novo robusno prilagođavanje pojačanja RST regulatora za sustav za pretvorbu energije vjetra (WECS) s dvostruko napajanim asinkronim generatorom (DFIG). Prije svega istražena je sinteza neizrazitog prilagođavanja pojačanja RST regulatora u kojem su neizrazita pravila iskorištena on-line za adaptaciju parametara RST regulatora koji koristi signal pogreške i njegovu prvu vremensku derivaciju. Cilj rada primjena je i usporedba dinamičkih svojstava dva tipa regulatora (polinomski RST i neizraziti RST) za WECS. Također je prikazano vektorsko upravljanje s orijentacijom statorskog toka DFIG-a za postizanje upravljanja aktivnom i reaktivnom snagom vjetroagregata koja se predaje mreži te za prilagodbu vjetroagregata za različita ograničenja. Rezultati prikupljeni provedenim simulacijama pokazuju efektivnost predloženog regulatora kroz rasrpegnutost, robusnost i dinamičke performanse za različite uvjete rada

    Machine learning for predicting fracture strain in sheet metal forming

    Get PDF
    Machine learning models are built to predict the strain values for which edge cracking occurs in hole expansion tests. The samples from this test play the role of sheet metal components to be manufactured, in which edge cracking often occurs associated with a uniaxial tension stress state at the critical edges of components. For the construction of the models, a dataset was obtained experimentally for rolled ferritic carbon steel sheets of different qualities and thicknesses. Two types of tests were performed: tensile and hole expansion tests. In the tensile test, the yield stress, the tensile strength, the strain at maximum load and the elongation after fracture were determined in the rolling and transverse directions. In the hole expansion test, the strain for which edge cracking occurs, was determined. It is intended that the models can predict the strain at fracture in this test, based on the knowledge of the tensile test data. The machine learning algorithms used were Multilayer Perceptron, Gaussian Processes, Support Vector Regression and Random Forest. The traditional polynomial regression that fits a 2nd order polynomial function was also used for comparison. It is shown that machine learning-based predictive models outperform the traditional polynomial regression method; in particular, Gaussian Processes and Support Vector Regression were found to be the best machine learning algorithms that enable the most robust predictive models.publishe

    An Interim Report on the Editorial and Analytical Work of the AnonymClassic Project

    Get PDF
    In this collective article, members of the AnonymClassic project discuss various aspects of their work on the textual tradition Kalīla and Dimna. Beatrice Gruendler provides a general introduction to the questions being considered. This is followed by a number of short essays in specific areas, organized into three categories: codicology, literary history and theory, and the digital infrastructure of the project. Jan J. van Ginkel summarizes the challenges involved in editing the Syriac versions of Kalīla and Dimna; Rima Redwan explains the AnonymClassic team’s approach vis-à-vis the transcription and textual segmentation of Arabic manuscripts; Khouloud Khalfallah follows this with an overview of the types of data that are recorded for each codex that is integrated into the project; Beatrice Gruendler, in a second contribution, shares some preliminary results from the analysis of interrelationships among manuscripts; and Rima Redwan, also in a second contribution, discusses the sets of illustrations, or »image cycles«, that are found in many copies of Kalīla wa-Dimna. Moving into the realm of literary history and theory, Isabel Toral poses a range of questions relating to the status of Kalīla and Dimna, as (arguably) anonymous in authorship and as a fundamentally translated book; Johannes Stephan explores the references to Kalīla wa-Dimna found in various medieval Arabic scholarly works; and Matthew L. Keegan confronts the problem of the genre(s) to which Kalīla wa-Dimna might be assigned and the exceptional »promiscuity« of the text. The last section of the article, on digital infrastructure, contains two contributions: Theodore S. Beers describes a web application that the team has created to facilitate the consultation of published versions of Kalīla and Dimna, and, finally, Mahmoud Kozae and Marwa M. Ahmed offer a more comprehensive discussion of the digital tools and methods – specialized and in some cases developed »in-house« – on which the AnonymClassic project relies

    Medium-spin states in neutron-rich 83As and 81As

    No full text
    The 83,81 As nuclei have been produced as fission fragments in the fusion reaction 18O + 208Pb at 85 MeV bombarding energy and studied with the Euroball array. Medium-spin states of 83,81 As have been established up to ∼3.5 MeV excitation energy. From angular correlation analysis, spin values have been assigned to most of the 81 As excited states. The behaviors of the yrast structures identified in this work are discussed in comparison with the general features known in the mass region. Then they are compared to the results of two theoretical approaches: the "rotor + quasiparticle" for 81 As and the shell model using the effective interactions JUN45 for 83,81 As

    New high-spin states of 58142^{142}_ {58}Ce and 56140^{140}_{56}Ba from fusion-fission reactions: Proton excitations in the N = 84 isotones

    Get PDF
    High-spin states in the 142^{142}Ce and 140^{140}Ba nuclei have been populated in the 12^{12}C + 238^{238}U and 18^{18}O + 208^{208}Pb fusion-fission reactions at 90 MeV and 85 MeV bombarding energy, respectively. The emitted γ\gamma-radiation was detected using the Euroball III and IV arrays. The high-spin yrast and near-to-yrast structures of 142^{142}Ce have been considerably extended. The level scheme of 140^{140}Ba has been extended by six new levels. The newly observed structures in these N = 84 isotones are discussed by analogy with the neighbouring nuclei

    Nucleic Acids Res

    Get PDF
    Fragile X syndrome (FXS), the most common form of inherited intellectual disability, is caused by the silencing of the FMR1 gene encoding an RNA-binding protein (FMRP) mainly involved in translational control. We characterized the interaction between FMRP and the mRNA of GRK4, a member of the guanine nucleotide-binding protein (G protein)-coupled receptor kinase super-family, both in vitro and in vivo. While the mRNA level of GRK4 is unchanged in the absence or in the presence of FMRP in different regions of the brain, GRK4 protein level is increased in Fmr1-null cerebellum, suggesting that FMRP negatively modulates the expression of GRK4 at the translational level in this brain region. The C-terminal region of FMRP interacts with a domain of GRK4 mRNA, that we called G4RIF, that is folded in four stem loops. The SL1 stem loop of G4RIF is protected by FMRP and is part of the S1/S2 sub-domain that directs translation repression of a reporter mRNA by FMRP. These data confirm the role of the G4RIF/FMRP complex in translational regulation. Considering the role of GRK4 in GABAB receptors desensitization, our results suggest that an increased GRK4 levels in FXS might contribute to cerebellum-dependent phenotypes through a deregulated desensitization of GABAB receptors
    corecore