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The Semantic Web: An Introduction

The Semantic Web: An Introduction
This document is designed as being a simple but comprehensive introductory publication for anybody trying to get into the Semantic Web: from beginners through to long time hackers. Recommended pre-reading: the Semantic Web in Breadth. Table Of Contents What Is The Semantic Web? The Semantic Web is a mesh of information linked up in such a way as to be easily processable by machines, on a global scale. You can think of it as being an efficient way of representing data on the World Wide Web, or as a globally linked database. The Semantic Web was thought up by Tim Berners-Lee, inventor of the WWW, URIs, HTTP, and HTML. What's the rationale for such a system? So the Semantic Web can be seen as a huge engineering solution... but it is more than that. URI - Uniform Resource Identifier A URI is simply a Web identifier: like the strings starting with "http:" or "ftp:" that you often find on the World Wide Web. RDF - Resource Description Framework A triple can simply be described as three URIs. Logic

Clojure for the Semantic Web - Digital Digressions by Stuart Sie I dropped in to hear Rich Hickey talk about Clojure at the New York Semantic Web meetup group. Some highlights: • Some programs, like compilers or theorem provers, are themselves functions. They take input and produce output. Purely functional languages like Haskell are good for these kinds of programs. • Most Clojure programmers go through an arc. • Rich recommended a paper, Out of the Tar Pit, for a discussion of functional and relational techniques to manage state. • Clojure’s data structures are persistent. • The first thing Rich did when experimenting with the semantic web was to pull data out of the Jena API and get it into Clojure data structures. Screencasts and code from the talk should appear soon — watch or the Clojure Google group for an announcement.

RDF - Semantic Web Standards Overview RDF is a standard model for data interchange on the Web. RDF has features that facilitate data merging even if the underlying schemas differ, and it specifically supports the evolution of schemas over time without requiring all the data consumers to be changed. RDF extends the linking structure of the Web to use URIs to name the relationship between things as well as the two ends of the link (this is usually referred to as a “triple”). Using this simple model, it allows structured and semi-structured data to be mixed, exposed, and shared across different applications. This linking structure forms a directed, labeled graph, where the edges represent the named link between two resources, represented by the graph nodes. Recommended Reading The RDF 1.1 specification consists of a suite of W3C Recommendations and Working Group Notes, published in 2014. A number of textbooks have been published on RDF and on Semantic Web in general. Discussions on a possible next version of RDF

Guide to the semantic web Greasy Fork - scripts de usuario útiles y seguros The Rise of Contextual User Interfaces Web 2.0 has brought many wonderful innovations and ideas to the Internet. We can no longer imagine the web without a social dimension, and we can no longer imagine an online world that is read-only - it is now a read/write web full of user-generated content. But there is another fairly recent innovation, which might have just as profound implications. We're speaking of the contextual user interface. Even five years ago we lived in the boxed world of Windows-dominated UIs. There were standard UI elements - menus, tabs, combo boxes, tables - and every single desktop application was full of these elements and nothing else. Strikingly, the recent wave of UI innovation is proving exactly the opposite. Windows UI - The World Of Never-Ending Choices Looking back at the years when Windows dominated our lives one can hardly believe what we put up with. Every imaginable choice was thrown at users at once and it was up to the poor user to figure out what to do. Apple's Revenge

Las relaciones familiares de todas las lenguas de Europa, explicadas en este brillante mapa Europa es un crisol de lenguas: un vivero que comienza en Tarifa y termina en el Ártico a través del cual conviven y se relacionan entre sí un centenar de lenguas de la más variopinta procedencia. Hay de todo, desde herencias deformadas y antiquísimas del latín hasta monstruos deformes que han terminado dominando el mundo, pasando por idiomas arcanos e ignotos y lenguas que provienen más allá del muro. Si no eres lingüista, hacerse una idea de cómo se relacionan entre sí y de dónde provienen las principales lenguas (y las más pequeñitas) puede convertirse en un quebradero de cabeza. El último y más espectacular con el que nos hemos topado es este realizado por Alternative Transport, un divertido blog anglosajón que atraviesa algunas de nuestras pequeñas obsesiones (transporte, mapas, idiomas, etcétera). El objetivo del mapa es ilustrar cómo de cerca o de lejos están los idiomas entre sí. Las urálicas, incluyendo la lengua húngara, ugria. Las lenguas celtas. Restan los pesos pesados.

Semantic Web in the news Well, the Semantic Web has been in the news a bit recently. There was the buzz about Twine, a "Semantic Web company", getting another round of funding. Then, Yahoo announced that it will pick up Semantic Web information from the Web, and use it to enhance search. And now the Times online mis-states that I think "Google could be superseded". Text search engines are of course good for searching the text in documents, but the Semantic Web isn't text documents, it is data. One thing to always remember is that the Web of the future will have BOTH documents and data. The "Google will be superseded" headline is an unfortunate misunderstanding. Now of course, as the name of The Times was once associated with a creditable and independent newspaper :-), the headline was picked up and elaborated on by various well-meaning bloggers. I note that here the blogosphere was misled by an online version of a conventional organ. A great example of Semantic Web data which works this way is Linked Data.

WhatsApp Ghost, usa WhatsApp sin que se refleje tu última conexión (Android) A pesar de las muchas quejas sobre su seguridad, WhatsApp sigue siendo el cliente de mensajería móvil más popular y empleado por usuarios de todo el mundo. Otra de las características de esta aplicación que no gusta a bastantes de sus usuarios es que se refleje la última conexión, es decir la última vez que abrimos el programa y participamos de WhatsApp. Si formas parte de este segundo grupo, de los que están molestos con que WhatsApp muestre la última vez que se conectaron, puedes evitarlo con la ayuda de una aplicación llamada WhatsApp Ghost. Se trata de una app gratuita para Android que no incluye publicidad, mejor que mejor. El primer paso, como es obvio, es instalarla, después deberás recordar pulsar sobre el icono de WhatsApp Ghost antes de abrir WhatsApp. Si recuerdas este sencillo paso no se reflejará tu conexión, podrás leer todos los mensajes e incluso contestarlos para que se envíen al cerrar WhatsApp Ghost.