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Conformal moduli of symmetric circular quadrilaterals with cusps. ETNA - Electronic Transactions on Numerical Analysis
No full textWe investigate moduli of planar circular quadrilaterals that are symmetric with respect to both coordinate axes. First we develop an analytic approach that reduces this problem to ODEs and then devise a numerical method to find out the accessory parameters. This method uses the Schwarz equation to determine a conformal mapping of the unit disk onto a given circular quadrilateral. We also give an example of a circular quadrilateral for which the value of the conformal modulus can be found in analytic form. This example is used to validate the numeric calculations. We also apply another method, the so called hpFEM, for the numerical calculation of the moduli. These two different approaches provide results agreeing with high accuracy
Multi-Feature Sample Database for Enhancing Deep Learning Tasks in Operational Humanitarian Applications. GI_Forum|GI_Forum 2021, Volume 1|
No full textAmongst the many benefits of remote sensing techniques in disaster- or conflict-related applications, timeliness and objectivity may be the most critical assets. Recently, increasing sensor quality and data availability have shifted the attention more towards the information extraction process itself. With promising results obtained by deep learning (DL), the notion arises that DL is not agnostic to input errors or biases introduced, in particular in sample-scarce situations. The present work seeks to understand the influence of different sample quality aspects propagating through network layers in automated image analysis. In this paper, we broadly discuss the conceptualisation of such a sample database in an early stage of realisation: (1) inherited properties (quality parameters of the underlying image such as cloud cover, seasonality, etc.); (2) individual (i.e., per-sample) properties, including a. lineage and provenance, b. geometric properties (size, orientation, shape), c. spectral features (standardized colour code); (3) context-related properties (arrangement Several hundred samples collected from different camp settings were hand-selected and annotated with computed features in an initial stage. The supervised annotation routine is automated so that thousands of existing samples can be labelled with this extended feature set. This should better condition the subsequent DL tasks in a hybrid AI approach
Coarsening in algebraic multigrid using Gaussian processes. ETNA - Electronic Transactions on Numerical Analysis
No full textMultigrid methods have proven to be an invaluable tool to efficiently solve large sparse linear systems arising in the discretization of Partial Differential Equations (PDEs). Algebraic multigrid methods and in particular adaptive algebraic multigrid approaches have shown that multigrid efficiency can be obtained without having to resort to properties of the PDE. Yet the required setup of these methods poses a not negligible overhead cost. Methods from machine learning have attracted attention to streamline processes based on statistical models being trained on the available data. Interpreting algebraically smooth error as an instance of a Gaussian process, we develop a new, data driven approach to construct adaptive algebraic multigrid methods. Based on Gaussian a priori distributions, kriging interpolation minimizes the mean squared error of the a posteriori distribution, given the data on the coarse grid. Going one step further, we exploit the quantification of uncertainty in the Gaussian process model in order to construct efficient variable splittings. Using a semivariogram fit of a suitable covariance model we demonstrate that our approach yields efficient methods using a single algebraically smooth vector
U3. Der römische Limes in Österreich|Das Heiligtum des Jupiter Optimus Maximus auf dem Pfaffenberg/Carnuntum Band 3 Der römische Limes in Österreich, Heft 49|Teil 1 Der römische Limes in Österreich, Heft 49|
No full textTitelei. Internationale Geschichte/International History|Die polnische Frage und der Wiener Kongress 1814–1815 Internationale Geschichte/International History Band 6|
No full textIntentions and Childbearing
No full textThe adult life of women and men is characterised by a plurality of choices and eventspertaining to different life domains. In the literature pregnancy intentions are usuallystudied in isolation from intentions pertaining to other spheres of life. In this research,we investigate the correspondence of birth intentions and birth outcome in a life courseframework, encompassing several life domains such as partnership, education, workand residence. Using longitudinal data from the Generations and Gender Surveys in fiveEuropean countries (Austria, Bulgaria, France, Hungary, and Lithuania), we examine thematching processes of individuals’ childbearing intentions and subsequent outcomespaying attention to the mediating and moderating role of intentions other thanchildbearing. We find empirical support for the hypothesis that adults’ plans aremultidimensional and that the more simultaneous intentions individuals have, the lesslikely they are to achieve their fertility goals. Some intentions, like moving to a newdwelling, facilitate the realization of birth intentions; others, like changing a job, tend tohinder the realisation of birth intentions. Finally, individuals are more successful inachieving their fertility targets in contexts that promote a reconciliation of work andfamily life
Production Regions and Technology of Pottery at Punta di Zambrone: NAA and Petrography in a Combined Approach. Orea|Punta di Zambrone I Oriental and European Archaeology Volume 17|
No full textWe analysed 37 samples of pottery and daub fragments from Punta di Zambrone (province of Vibo Valentia) by combining thin-section petrography and Neutron Activation Analysis (NAA) geochemistry. The aim is to identify possible production areas for some wheelmade vessels of Aegean type and better define raw materials and paste recipes for the local handmade impasto ware. By integrating petrographic and NAA results, one reliable group emerged, which refers to the local specialised production of Recent Bronze Age (RBA) open shapes. A filter test allowing larger elemental variances was applied on NAA data in order to identify further groups (named special groups) to be specifically compared with petrographic fabrics. The special NAA group Ul41 and petro group 3, including local reference materials such as daub fragments, correlate well. Furthermore, the concentration pattern of Ul41 is close to that of local clay deposits (Cava Monaca and Fiumara Jona). The RBA closed shapes show a lower correspondence between geochemical and petrographic results, presumably attributable to less standardised production processes
Die erste Fassung von Gregors Moralia in Iob – ein verschollener Text. Mit einer textkritischen Appendix zu Greg. M. epist. 1. Wiener Studien|Wiener Studien 134 134|
No full textP. Meyvaert claimed that traces of a first (oral) version of Gregory’s Moralia in Iob,which was preached, were preserved in Isidore’s Sententiae and in quotations by an anonymousauthor from Bec (Paris, BNF lat. 2342, s. XII). In a philological comparison, evidence isprovided that the Anonymus Beccensis does not quote Gregory’s lost first version, but isdependent on the Collationes of Odo of Cluny, who paraphrased Gregory freely. Isidore, too,cannot serve as a witness for Gregory’s first (oral) version because of his paraphrastictechnique. In a text-critical appendix on Greg. M. epist. 1,41: verbis sensibusque tepentibus,the variant repentibus (“with improvised words and thoughts”) is preferred
