220 research outputs found

    Idmb: a tool for navigating the Inspire data model and generating an Inspire SQL database and WFS Configuration

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    The Inspire Data Model Browser (IDMB) is a free tool that performs the following functions: (i) it presents the Inspire UML Data Model as a tree-based structure, which is complementary to the UML diagrams; (ii) it generates a Postgis SQL Script for creating an INSPIRE compliant SQL database (Inspire Database) and a configuration file for the Deegree tool that enables the access to the Inspire Database through a Web Feature Service (WFS) producing GML according to the Inspire XML Schemas

    Application of the GeoUML Tools for the Production and Validation of Inspire Datasets

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    The structure of INSPIRE datasets is oriented to the exchange of data, not to its storage and manipulation in a database. Therefore data transformation is required. This paper analyses the possibility of using in this context the tools developed by SpatialDBGroup at Politecnico di Milano in order to create and validate spatial databases. The considered scenario is the following one: - an organisation (data provider) is willing to provide WFS and GML conformant to INSPIRE specifications (services and data); - this organisation is hosting geodata related to one or more INSPIRE themes on a spatial relational database, called here Source Database - in order to facilitate the implementation of INSPIRE compliant GML data, the organisation implements a new "INSPIRE-structured" spatial database, called here INSPIRE Database - a Transformation Procedure is created which extracts the data from the Source Database and loads it into the INSPIRE Database - the INSPIRE Database is "validated" also using topological operators, in order to identify also topological constraints gaps. We assume that both the Source Database and the INSPIRE Database are SQL based and that their physical schemas have been generated by the GeoUML Catalogue tool from the corresponding conceptual schemas, called SCSOURCE and SCINSPIRE. In this scenario the availability of the conceptual schemas suggests different areas where the tools can provide a great benefit: 1. Creation of the GeoUML specification SCINSPIRE, automatic generation of the corresponding physical SQL structure and Validation of the INSPIRE Database with respect to the specification 2. (Semi)automatic generation of the Transformation Procedure using a set of correspondence rules between elements of SCSOURCE and SCINSPIRE 3. Automatic generation of the WFS configuration from the SCINSPIRE In this paper we describe the work which has already been done and the research directions which we are following in order to deal with these points

    What makes spatial data big? A discussion on how to partition spatial data

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    The amount of available spatial data has significantly increased in the last years so that traditional analysis tools have become inappropriate to effectively manage them. Therefore, many attempts have been made in order to define extensions of existing MapReduce tools, such as Hadoop or Spark, with spatial capabilities in terms of data types and algorithms. Such extensions are mainly based on the partitioning techniques implemented for textual data where the dimension is given in terms of the number of occupied bytes. However, spatial data are characterized by other features which describe their dimension, such as the number of vertices or the MBR size of geometries, which greatly affect the performance of operations, like the spatial join, during data analysis. The result is that the use of traditional partitioning techniques prevents to completely exploit the benefit of the parallel execution provided by a MapReduce environment. This paper extensively analyses the problem considering the spatial join operation as use case, performing both a theoretical and an experimental analysis for it. Moreover, it provides a solution based on a different partitioning technique, which splits complex or extensive geometries. Finally, we validate the proposed solution by means of some experiments on synthetic and real datasets

    Unexpected Stereoselective Access to 2-Aminooxazolines from Propargyl Ureas by Silver Salts under Mild Conditions

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    Propargyl ureas can lead to a range of possible heterocyclic compounds, mainly depending on the employed catalyst. Silver salts are known to promote the N-5-exo-dig cyclization mode to imidazolidinone derivatives. Conversely, a versatile and stereoselective O-5-exo-dig cyclization of propargyl ureas to 2-aminooxazolines by Ag(I) catalysis is here disclosed. Good to excellent yields and complete stereoselectivity of the external double bond have been achieved under milder reaction conditions(50–60°C). A one-po protocol starting from the corresponding propargylic amines and isocyanates has been developed as well. N,N’-Dipropargyl ureas underwent a uncommon O-5-exo-dig/N-5-endo-dig double cyclization sequence. Finally, insights into the tautomeric equilibrium of 2-aminooxazoles and on their relative reactivity are provided

    The Astronomical Orientation of Ancient Greek Temples

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    Despite its appearing to be a simple question to answer, there has been no consensus as to whether or not the alignments of ancient Greek temples reflect astronomical intentions. Here I present the results of a survey of archaic and classical Greek temples in Sicily and compare them with temples in Greece. Using a binomial test I show strong evidence that there is a preference for solar orientations. I then speculate that differences in alignment patterns between Sicily and Greece reflect differing pressures in the expression of ethnic identity

    Spontaneous and deliberate future thinking: A dual process account

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    © 2019 Springer Nature.This is the final published version of an article published in Psychological Research, licensed under a Creative Commons Attri-bution 4.0 International License. Available online at: https://doi.org/10.1007/s00426-019-01262-7.In this article, we address an apparent paradox in the literature on mental time travel and mind-wandering: How is it possible that future thinking is both constructive, yet often experienced as occurring spontaneously? We identify and describe two ‘routes’ whereby episodic future thoughts are brought to consciousness, with each of the ‘routes’ being associated with separable cognitive processes and functions. Voluntary future thinking relies on controlled, deliberate and slow cognitive processing. The other, termed involuntary or spontaneous future thinking, relies on automatic processes that allows ‘fully-fledged’ episodic future thoughts to freely come to mind, often triggered by internal or external cues. To unravel the paradox, we propose that the majority of spontaneous future thoughts are ‘pre-made’ (i.e., each spontaneous future thought is a re-iteration of a previously constructed future event), and therefore based on simple, well-understood, memory processes. We also propose that the pre-made hypothesis explains why spontaneous future thoughts occur rapidly, are similar to involuntary memories, and predominantly about upcoming tasks and goals. We also raise the possibility that spontaneous future thinking is the default mode of imagining the future. This dual process approach complements and extends standard theoretical approaches that emphasise constructive simulation, and outlines novel opportunities for researchers examining voluntary and spontaneous forms of future thinking.Peer reviewe
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