Understands the concept of Federated Searches. – Linked Data for Professional Education https://ld4pe.dublincore.org Learning resources tagged by competency Thu, 19 Nov 2020 14:45:03 +0000 en-US hourly 1 https://wordpress.org/?v=4.9.16 Linked Statistical Data Analysis https://ld4pe.dublincore.org/learning_resource/linked-statistical-data-analysis/ Sun, 13 Aug 2017 08:18:11 +0000 https://ld4pe.dublincore.org/learning_resource/linked-statistical-data-analysis/ Linked Data design principles are increasingly employed to publish and consume high-fidelity, heterogeneous statistical datasets in a distributed fashion. While vast amounts of linked statistics are available, access and reuse of the data is subject to expertise in corresponding technologies. There exists no user-centered interfaces for researchers, journalists and interested people to compare statistical data retrieved from different sources on the Web. Given that the RDF Data Cube vocabulary is used to describe statistical data, its use makes it possible to discover and identify statistical data artifacts in a uniform way. In this article, the design and implementation of a user-centric application and service is presented. Behind the scene, the platform utilizes federated SPARQL queries to gather statistical data from distributed data stores. The R language for statistical computing is employed to perform statistical analyses and visualizations. The Shiny application and server bridges the front-end Web user interface with R on the server-side in order to compare statistical macrodata, and stores analyses results in RDF for future research. As a result, distributed linked statistics with accompanying provenance data can be more easily explored and analysed by interested parties.

URL: http://csarven.ca/linked-statistical-data-analysis
Keywords: Data analysis, R (programming language), Shiny server, Apache Jena, Federated queries
Author: Riedl, Reinhard
Publisher: CEUR (Central Europe Workshop Proceedings)
Date created: 2013-07-07 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P1H
Educational use: professionalDevelopment
Educational audience: professional
Interactivity type: expositive

]]> Visualising The Location Graph With Gephi and Ordnance Survey Linked Data https://ld4pe.dublincore.org/learning_resource/visualising-the-location-graph-with-gephi-and-ordnance-survey-linked-data/ Sat, 14 Jan 2017 06:46:01 +0000 https://ld4pe.dublincore.org/learning_resource/visualising-the-location-graph-with-gephi-and-ordnance-survey-linked-data/ Building on a previous post, the author shares another example using a SPARQL endpoint to query Linked Open Data and turn the results into a graph (aka, "network") visualization using the Gephi tool (and its 'Semantic Web Import' plugin). Includes an example of federated search as well as a work-around to convert SPARQL results from Turtle to XML.

URL: https://johngoodwin225.wordpress.com/2014/03/28/visualising-the-location-graph-example-with-gephi-and-ordnance-survey-linked-data/
Keywords: Gephi, DBpedia, Geospatial data, SPARQL
Author: Goodwin, John
Date created: 2014-03-26 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M

]]> Wikidata SPARQL Query Tutorial https://ld4pe.dublincore.org/learning_resource/wikidata-sparql-query-tutorial/ Thu, 29 Dec 2016 06:44:05 +0000 https://ld4pe.dublincore.org/learning_resource/wikidata-sparql-query-tutorial/ This video presentation demonstrates how to construct SPARQL queries simply and easily using the Wikidata Query Service. It works through an example of searching for notable females educated at the University of Edinburgh, with results filtered by place of birth. The data is then visualized with images, timelines, maps, and in the new Timeline Viewer using Histropedia.

URL: https://www.youtube.com/watch?v=1jHoUkj_mKw
Keywords: Wikidata, Histropedia, SPARQL
Author: McAndrew, Ewan
Date created: 2016-09-02 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: professional
Interactivity type: expositive

]]> Federating SPARQL Queries Across Government Linked Data https://ld4pe.dublincore.org/learning_resource/federating-sparql-queries-across-government-linked-data/ Thu, 29 Dec 2016 06:44:02 +0000 https://ld4pe.dublincore.org/learning_resource/federating-sparql-queries-across-government-linked-data/ The author describes how to create a single SPARQL query which pulls Linked Data from two separate endpoints to answer complex questions in cases where all the necessary data cannot be found at a single source.

URL: https://johngoodwin225.wordpress.com/2014/03/22/federating-sparql-queries-across-government-linked-data/
Keywords: Government Open Data, Linked Open Data (LOD), SPARQL
Author: Goodwin, John
Date created: 2014-03-22 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M

]]> Linked Data and SPARQL Queries Tutorial https://ld4pe.dublincore.org/learning_resource/linked-data-and-sparql-queries-tutorial-2/ Wed, 30 Dec 2015 18:37:26 +0000 https://ld4pe.dublincore.org/learning_resource/linked-data-and-sparql-queries-tutorial-2/ This tutorial goes through some basic SPARQL queries in order to give the user a sense of how to discover and query different Linked Data (LD) sets. It seeks to answer, through some examples, the following questions:1. How do I know where to look to identify LD sets? 2. Once I know that a LD set of interest exists, how should I query it? 3. How do I query across different LD sets?

URL: http://ctsaconnect.org/system/files/Linked%20data%20and%20SPARQL%20queries%20tutorial.pdf
Keywords: Linked Data, Linked Open Data Cloud, Dataset, RDF, SPARQL, Query, SPARQL endpoint
Publisher: VIVO
Date created: 2012-01-01 07:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: generalPublic
Interactivity type: active

]]> Linked Data Query Processing: Introduction https://ld4pe.dublincore.org/learning_resource/linked-data-query-processing-introduction/ Tue, 20 Oct 2015 19:20:00 +0000 https://ld4pe.dublincore.org/learning_resource/linked-data-query-processing-introduction/ These slides represent the first of a five-part tutorial presentation given at the 22nd International World Wide Web Conference (WWW 2013). This introduction gives a quick overview of Linked Data principles and SPARQL endpoints, which are requirements for understanding the rest of the tutorial. The focuses then shifts to Linked Data query processing with emphasis on the specific challenges faced due to the differences between Linked Data and both central and distributed databases. The author argues that current paradigms for processing queries over Linked Data (SPARQL endpoint federation and warehousing) could be replaced by either a data retrieval approach, a result construction approach, or a combination of the new approaches with the traditional paradigms.

URL: http://dsg.uwaterloo.ca/LDQTut2013/LDQTut2013_1.pdf
Keywords: Data Warehousing, SPARQL endpoint, Web of Data
Author: Hartig, Olaf
Date created: 2013-05-14 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M
Educational use: instruction
Educational audience: professional
Interactivity type: expositive

]]> Learn About SPARQL 1.1 https://ld4pe.dublincore.org/learning_resource/learn-about-sparql-1-1/ Tue, 15 Sep 2015 02:33:10 +0000 https://ld4pe.dublincore.org/learning_resource/learn-about-sparql-1-1/ This S5 format slideshow details the changes made to the query language in SPARQL 1.1- it is not a basic introduction to SPARQL and assumes that the reader is already familiar with the basic functions of SPARQL 1.0.

URL: https://www.dajobe.org/talks/201105-sparql-11/
Keywords: Federated query, SPARQL
Author: Beckett, David
Date created: 2011-05-01 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: student
Interactivity type: expositive

]]> Querying Semantic Web Data with SPARQL (and SPARQL 1.1) https://ld4pe.dublincore.org/learning_resource/querying-semantic-web-data-with-sparql-and-sparql-1-1/ Tue, 15 Sep 2015 02:33:08 +0000 https://ld4pe.dublincore.org/learning_resource/querying-semantic-web-data-with-sparql-and-sparql-1-1/ This lengthy slide presentation covers SPARQL 1.1. It begins with the fundamentals: graph patterns, operators, and algebraic representations. The second half dives deeply into complex topics: semantics, property paths, navigational capabilities. Description Logics are used throughout to illustrate concepts.

URL: http://web.ing.puc.cl/~marenas/talks/BNCOD13.pdf
Keywords: SPARQL, Graph, Triple, RDF Schema
Author: Arenas, Marcelo
Date created: 2013-01-01 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P60M
Educational use: instruction
Educational audience: student
Interactivity type: expositive

]]> ELITE: An Entailment-based Federated Query Engine for Complete and Transparent Semantic Data Integration https://ld4pe.dublincore.org/learning_resource/elite-an-entailment-based-federated-query-engine-for-complete-and-transparent-semantic-data-integration/ Tue, 15 Sep 2015 02:33:08 +0000 https://ld4pe.dublincore.org/learning_resource/elite-an-entailment-based-federated-query-engine-for-complete-and-transparent-semantic-data-integration/ In recent years, the core of the Semantic Web has evolved to a conceptual layer built by a set of ontologies mapped onto data distributed in numerous data sources which are interlinked, interpreted and processed in terms of semantics. In this context federated querying of Linked Data becomes a central issue. This paper presents the federated query engine ELITE, which facilitates a complete and transparent integration and querying of distributed autonomous data sources.

URL: http://www.semanco-project.eu/index_htm_files/ELITE.pdf
Keywords: Description Logics, Query rewriting, Web Ontology Language (OWL), Entailment Regimes, Ontology-based Data Access (OBDA)
Author: Nolle, Andreas
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P45M
Educational use: professionalDevelopment
Educational audience: professional

]]> Querying Linked Data with SPARQL https://ld4pe.dublincore.org/learning_resource/querying-linked-data-with-sparql/ https://ld4pe.dublincore.org/learning_resource/querying-linked-data-with-sparql/#respond Thu, 13 Aug 2015 03:26:21 +0000 https://ld4pe.dublincore.org/learning_resource/querying-linked-data-with-sparql/ This slideset was part of the "How to Consume Linked Data" tutorial at the International Semantic Web Conference (ISWC), Oct. 2009. Predates SPARQL 1.1, so some of the information on federated queries may be outdated. However, this resource is of particular interest to those wishing to learn about automated link traversal.

URL: http://www.slideshare.net/olafhartig/querying-linked-data-with-sparql?related=2
Keywords: SQUIN, SPARQL endpoint, Link traversal based query execution (LTBQE), Automated link traversal
Author: Hartig, Olaf
Date created: 2009-10-25 07:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P45M
Educational use: instruction
Educational audience: generalPublic
Interactivity type: expositive

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