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Index. Projet. PostGIS on Amazon RDS: A Spatial Database in the Cloud. IT (513) What is Linked Data? Croiser des statistiques : l’enjeu des URI. Voilà un cas pratique qui vient de tomber pour illustrer une utilisation "simple" (oserai-je "intuitive" ?)

Croiser des statistiques : l’enjeu des URI

Des URI. L’enjeu Il y a quelques jours, Symac a initié sur Bibliopedia une page Services numériques en BU, afin de pouvoir décrire et comparer les "services numériques" (au sens décrit dans un précédent billet, c’est-à-dire avec toute la diversité des tâches qui vont ou non rentrer dans cette appellation) entre eux. Si ce genre de tableau est intéressant, il est à mon sens forcément insuffisant : savoir qu’il y a 3 ou 10 personnes dans un tel service n’est vraiment utile que si ça peut devenir un outil d’aide à la décision, par exemple dans le cadre d’une réflexion sur une réorganisation interne.

Rdf. RDFa. Rdfonthego - RDF store and query processor. RDF On The Go is the project to build a persistent RDF store and query processor on Android phone.

rdfonthego - RDF store and query processor

For storage of the data, RDF on The Go uses a lightweight version of the Berkeley DB that is suitable for mobile devices, which provides a B-Tree implementation for accessing the RDF graphs. For each RDF node, the system employs dictionary encoding where node values are mapped to integer identi ers. This reduces the space required to store each RDF node, since the encoded version of the nodes are considerably smaller than the original ones. Moreover, dictionary encoding also allows faster processing, since integer comparisons are cheaper. Fast lookups are achieved in a two-step approach: fi rst, each triple node is stored in multiple ways with different orderings of the triple elements, similar to Hẽxastore. To encourage developers to use RDF On the Go to build their applications, we have adapted the core APIs of Jena and ARQ to the Android environment. What is RDF and what is it good for? How RDF Databases Differ from Other NoSQL Solutions - The Datagraph Blog.

This started out as an answer at Semantic Overflow on how RDF database systems differ from other currently available NoSQL solutions.

How RDF Databases Differ from Other NoSQL Solutions - The Datagraph Blog

I've here expanded the answer somewhat and added some general-audience context. RDF database systems are the only standardized NoSQL solutions available at the moment, being built on a simple, uniform data model and a powerful, declarative query language. These systems offer data portability and toolchain interoperability among the dozens of competing implementations that are available at present, avoiding any need to bet the farm on a particular product or vendor. In case you're not familiar with the term, NoSQL ("Not only SQL") is a loosely-defined umbrella moniker for describing the new generation of non-relational database systems that have sprung up in the last several years.

These systems tend to be inherently distributed, schema-less, and horizontally scalable. RDF Web Applications Working Group. Current and Upcoming Events Teleconferences: The first Thursday of each month at 10am US Eastern time.

RDF Web Applications Working Group

An agenda is sent to rdfa-wg 24 hours in advance; minutes follow within a day or two. Will be monitoring comments on any specification or test cases W3C Standards and Notes HTML+RDFa 1.1 (REC) This specification defines rules and guidelines for adapting the RDFa Core 1.1 and RDFa Lite 1.1 specifications for use in HTML5 and XHTML5.

RDF and Mind Maps. Kerstin Forsberg has written an article about mind maps and how the concept of mapping the mind calls for RDF triples and formal models.

RDF and Mind Maps

She writes, “When I see these mind maps I see graphs just begging for RDF triples (subject, predicate, object)… An interesting exercise would be to have the Parkinson’s disease example completed in the concept mapping tool (CMAP) the whole way down to SDTM. And export the mind maps using as RDF triples.” She goes on, “When I these mind maps I can also see how easy it is to start drawing such diagrams and exporting them as representations of generic mind maps.

However, to fulfill the ultimate goal to have them ’captured in a way that these can be used both for human understanding and for computer interpretation’ the ‘mind maps’ need underlying formal models of the clinical and biomedical reality. Therefore, I see an interesting connection between the high level maps for disease and clinical processes to the Ontology for General Medical Science (OGMS). Introduction to: RDF vs XML. RDF triple stores — an overview. There's a huge range of triple stores out there, and it's not trivial to find the one most suited for your exact needs.

RDF triple stores — an overview

I reviewed all those I could find earlier this year for a project, and here is the result. I've evaluated the stores against the requirements that mattered for that particular project. I haven't summarized the scores, as everyone's weights for these requirements will be different. How RDF Databases Differ from Other NoSQL Solutions - The Datagraph Blog.

Pour aller plus loin avec RDFa. Je répète à longueur de temps que structurer un contenu en XML, et a fortiori en HTML, ne constitue pas une sémantisation, mais permet d'indiquer le rôle joué par la portion d'information dans le contexte d'un document.

Pour aller plus loin avec RDFa

Les normes du Web sémantique ont à l'inverse vocation à aider à la sémantisation du contenu. Mais, à force de le répéter sans rien montrer de probant, vous allez finir par croire que c'est une chimère. Soyons clairs, nous sommes encore loin du compte, mais nous avons fait des avancées, exemple avec RDFa. RDFa fait déjà énormément parler de lui, comme le prouvera ma prochaine pelote. Transforming Relational Data to RDF – R2RML Becomes Official W3C Recommendation. Today, the World Wide Web Consortium announced that R2RML has achieved Recommendation status.

Transforming Relational Data to RDF – R2RML Becomes Official W3C Recommendation

As stated on the W3C website, R2RML is “a language for expressing customized mappings from relational databases to RDF datasets. Such mappings provide the ability to view existing relational data in the RDF data model, expressed in a structure and target vocabulary of the mapping author’s choice.” In the life cycle of W3C standards creation, today’s announcement means that the specifications have gone through extensive community review and revision and that R2RML is now considered stable enough for wide-spread distribution in commodity software.

Richard Cyganiak, one of the Recommendation’s editors, explained why R2RML is so important. “In the early days of the Semantic Web effort, we’ve tried to convert the whole world to RDF and OWL. RGI_Version1 0.pdf. RDF: The Basics. Publier des stats en RDF (1) : ébauche et errances.