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DCMI Webinar: "From 0 to 60 on SPARQL queries in 50 minutes" (Redux)

Mon, 03/30/2015 - 23:59

Categories:

RDF
2015-03-30, This webinar with Ethan Gruber on 13 May provides an introduction to SPARQL, a query language for RDF. Users will gain hands on experience crafting queries, starting simply, but evolving in complexity. These queries will focus on coinage data in the SPARQL endpoint hosted by http://nomisma.org: numismatic concepts defined in a SKOS-based thesaurus and physical specimens from three major museum collections (American Numismatic Society, British Museum, and Münzkabinett of the Staatliche Museen zu Berlin) linked to these concepts. Results generated from these queries in the form of CSV may be imported directly into Google Fusion Tables for immediate visualization in the form of charts and maps. Additional information and free registration is available at http://dublincore.org/resources/training/#2015gruber. Redux: This webinar was first presented as a training session in the LODLAM Training Day at SemTech2014.

National Diet Library of Japan publishes translations of key DCMI specifications

Mon, 03/30/2015 - 23:59

Categories:

RDF
2015-03-30, DCMI is please to announce that the National Diet Library, the sole national library in Japan, has translated the DCMI Metadata Terms and the Singapore Framework for Dublin Core Application Profiles into Japanese. The links to the new Japanese translations, as well as others are available on the DCMI Documents Translation page at http://dublincore.org/resources/translations/index.shtml.

A little stepper motor

Sun, 03/29/2015 - 19:08

Categories:

RDF

I want to make a rotating 3D-printed head-on-a-spring for my

Two AKSW Papers at ESWC 2015

Tue, 03/24/2015 - 12:38

Categories:

RDF

We are very pleased to announce that two of our papers were accepted for presentation as full research papers at ESWC 2015.

Automating RDF Dataset Transformation and Enrichment (Mohamed Ahmed Sherif, Axel-Cyrille Ngonga Ngomo, and Jens Lehmann)

With the adoption of RDF across several domains, come growing requirements pertaining to the completeness and quality of RDF datasets. Currently, this problem is most commonly addressed by manually devising means of enriching an input dataset. The few tools that aim at supporting this endeavour usually focus on supporting the manual definition of enrichment pipelines. In this paper, we present a supervised learning approach based on a refinement operator for enriching RDF datasets. We show how we can use exemplary descriptions of enriched resources to generate accurate enrichment pipelines. We evaluate our approach against eight manually defined enrichment pipelines and show that our approach can learn accurate pipelines even when provided with a small number of training examples.

HAWK – Hybrid Question Answering using Linked Data (Ricardo Usbeck, Axel-Cyrille Ngonga Ngomo, Lorenz Bühmann, and Christina Unger)

The decentral architecture behind the Web has led to pieces of information being distributed across data sources with varying structure. Hence, answering complex questions often required combining information from structured and unstructured data sources. We present HAWK, a novel entity search approach for Hybrid Question Answering based on combining Linked Data and textual data. The approach uses predicate-argument representations of questions to derive equivalent combinations of SPARQL query fragments and text queries. These are executed so as to integrate the results of the text queries into SPARQL and thus generate a formal interpretation of the query. We present a thorough evaluation of the framework, including an analysis of the influence of entity annotation tools on the generation process of the hybrid queries and a study of the overall accuracy of the system. Our results show that HAWK achieves 0.68 respectively 0.61 F-measure within the training respectively test phases on the Question Answering over Linked Data (QALD-4) hybrid query benchmark.

Come over to ESWC and enjoy the talks. Best regards, Sherif on behalf of AKSW

AKSW Colloquium, 03-23-2015, Git Triple Store and From CPU bringup to IBM Watson

Mon, 03/23/2015 - 09:58

Categories:

RDF
From CPU bring up to IBM Watson by Kay Müller, visiting researcher, IBM Ireland

Working in a corporate environment like IBM offers many different opportunities to work on the bleeding edge of research and development. In this presentation Kay Müller, who is currently a Software Engineer in the IBM Watson Group, is going to give a brief overview of some of the projects he has been working on in IBM. These projects range from a CPU bring up using VHDL to the design and development of a semantic search framework for the IBM Watson system.

Git Triple Store by Natanael Arndt

In a setup of distributed clients resp. applications with different actors writing on the same knowledge base (KB) a synchronization of distributed copies of the KB, an edit history with provenance information and a management for different versions of the KB in parallel are needed. The aim is to design and construct a Triple Store back end which records any change on triple-level and enables distributed curation of RDF-graphs. This should be achieved by using a distributed revision control system for holding a serialization of the RDF-graph. Natanael Arndt will present the paper “R&Wbase: Git for triples” by Miel Vander Sande et al. published at LDOW2013 as related work. Additionally, he will present his ideas towards a colaboration infrastructure using DVCS for triples.

 

About the AKSW Colloquium

This event is part of a series of events about Semantic Web technology. Please see http://wiki.aksw.org/Colloquium for further information about previous and future events. As always, Bachelor and Master students are able to get points for attendance and there is complimentary coffee and cake after the session.

 

AKSW Colloquium, 03-23-2015, Query Tree Learner and From CPU bringup to IBM Watson

Mon, 03/23/2015 - 09:58

Categories:

RDF
From CPU bring up to IBM Watson by Kay Müller, visiting researcher, IBM Ireland

Working in a corporate environment like IBM offers many different opportunities to work on the bleeding edge of research and development. In this presentation Kay Müller, who is currently a Software Engineer in the IBM Watson Group, is going to give a brief overview of some of the projects he has been working on in IBM. These projects range from a CPU bring up using VHDL to the design and development of a semantic search framework for the IBM Watson system.

Git Triple Store by Natanael Arndt In a setup of distributed clients resp. applications with different actors writing on the same knowledge base (KB) you need Synchronization of distributed copies of the KB, an edit history with provenance information and a management for different versions of the KB in parallel. The aim is to design and construct a Triple Store back end which records any change on Triple level and enables distributed curation of RDF-graphs. This should be achieved by using a distributed revision control system for holding a serialization of the RDF-graph.

Today I will present the paper “R&Wbase: Git for triples” by Miel Vander Sande et al. published at LDOW2013 as related work. Additionally I will present my ideas towards a colaboration infrastructure for a DVCS for triples.

 

About the AKSW Colloquium

This event is part of a series of events about Semantic Web technology. Please see http://wiki.aksw.org/Colloquium for further information about previous and future events. As always, Bachelor and Master students are able to get points for attendance and there is complimentary coffee and cake after the session.

 

Tiny micro servo 9g and Duemilanove w/ ATmega168

Sat, 03/21/2015 - 18:43

Categories:

RDF

It’s eons since I messed with an Arduino, and I’ve forgotten it all. All I have handy is a Duemilanove with ATmega168 and the newish version of the Arduino IDE doesn’t have Duemilanove ATmega168 as an option. Following

Gradle, etc.

Tue, 03/17/2015 - 02:01

Categories:

RDF
A few thoughts on improving build processes.

DCMI Webinar: "Approaches to Making Dynamic Data Citable: Recommendations of the RDA Working Group"

Mon, 03/16/2015 - 23:59

Categories:

RDF
2015-03-16, Being able to reliably and efficiently identify entire or subsets of data in large and dynamically growing or changing datasets constitutes a significant challenge for a range of research domains. In order to repeat an earlier study, to apply data from an earlier study to a new model, we need to be able to precisely identify the very subset of data used. While verbal descriptions of how the subset was created (e.g. by providing selected attribute ranges and time intervals) are hardly precise enough and do not support automated handling, keeping redundant copies of the data in question does not scale up to the big data settings encountered in many disciplines today. Furthermore, we need to be able to handle situations where new data gets added or existing data gets corrected or otherwise modified over time. Conventional approaches, such as assigning persistent identifiers to entire data sets or individual subsets or data items, are thus not sufficient. In this webinar, Andreas Rauber will review the challenges identified above and discuss solutions that are currently elaborated within the context of the working group of the Research Data Alliance (RDA) on Data Citation: Making Dynamic Data Citeable. The approach is based on versioned and time-stamped data sources, with persistent identifiers being assigned to the time-stamped queries/expressions that are used for creating the subset of data. We will further review results from the first pilots evaluating the approach. Additional information and registration available at http://dublincore.org/resources/training/#2015rauber.

Open Semantic Framework 3.3 Released

Wed, 03/04/2015 - 22:18

Categories:

RDF
Structured Dynamics is happy to announce the immediate availability of the Open Semantic Framework version 3.3. This new release of OSF lets system administrators choose between two different communication channels to send SPARQL queries to the triple store:
  1. HTTP
  2. ODBC

In OSF 3.1, the only communication channel available was a ODBC channel using the iODBC drivers. In OSF 3.2, the only communication channel available was a HTTP channel. What we did with OSF 3.3 is to let the system administrator choose between the two.

Quick Introduction to the Open Semantic Framework

What is the Open Semantic Framework?

The Open Semantic Framework (OSF) is an integrated software stack using semantic technologies for knowledge management. It has a layered architecture that combines existing open source software with additional open source components. OSF is designed as an integrated content platform accessible via the Web, which provides needed knowledge management capabilities to enterprises. OSF is made available under the Apache 2 license.

OSF can integrate and manage all types of content â€" unstructured documents, semi-structured files, spreadsheets, and structured databases â€" using a variety of best-of-breed data indexing and management engines. All external content is converted to the canonical RDF data model, enabling common tools and methods for tagging and managing all content. Ontologies provide the schema and common vocabularies for integrating across diverse datasets. These capabilities can be layered over existing information assets for unprecedented levels of integration and connectivity. All information within OSF may be powerfully searched and faceted, with results datasets available for export in a variety of formats and as linked data.

Why Multiple Channels in OSF?

Historically, OSF only used the ODBC channel to communicate with Virtuoso, and it was using the iODBC drivers. As explained in a previous blog post, the fact that we were using the iODBC drivers in Ubuntu was adding a lot of complexity into the system since we had to recompile most of the PHP packages to use that other ODBC driver.

With OSF 3.2, we refactored the code such that we could query any SPARQL HTTP endpoint. The goal of this current improvement is to be able to use any triple store that has a compatible SPARQL HTTP endpoint with OSF, and not just Virtuoso.

With OSF 3.3, what we choose to do is to make both options a possibility. However, what we did is to make sure that the latest version of Virtuoso was now properly working with the unixODBC drivers, which are shipped by default with Ubuntu.

This means that people can now use the ODBC channel, but using the unixODBC drivers instead. The end result of this enhancement is that it makes the maintenance of a Ubuntu/OSF instance much easier since no packages are on hold, and that the PHP5 packages can be updated at any time without needing to be recompiled using the iODBC drivers.

Deploying a New OSF 3.3 Server Using the OSF Installer

OSF 3.3 can easily be deployed on a Ubuntu 14.04 LTS server using the osf-installer application. The deployment is done by executing the following commands in your terminal:

mkdir -p /usr/share/osf-installer/

cd /usr/share/osf-installer/

wget https://raw.github.com/structureddynamics/Open-Semantic-Framework-Installer/3.3/install.sh

chmod 755 install.sh

./install.sh

./osf-installer --install-osf -v Using an Amazon AMI

If you are an Amazon AWS user, you also have access to a free AMI that you can use to create your own OSF instance. The full documentation for using the OSF AMI is available here.

Upgrading Existing Installations

It is not possible to automatically upgrade previous versions of OSF to OSF 3.3. It is possible to upgrade an older instance of OSF to OSF version 3.3, but only manually. If you have this requirement, just let me know and I will write about the upgrade steps that are required to upgrade these instances to OSF version 3.3.

Conclusion

This new version of the Open Semantic Framework should be even simpler to install, deploy and maintain. Several additional small updates have also provided in this new version to other aspects of installation simpler and faster.

A writable Web based on LDP

Tue, 03/03/2015 - 16:34

Categories:

RDF
Last week has marked the culmination of almost three years of hard work coming out of the Linked Data Platform WG, resulting in the publication of the Linked Data Platform 1.0 as a W3C Recommendation. For those of you not yet familiar with … Continue reading →

ALIGNED project kick-off

Tue, 03/03/2015 - 11:43

Categories:

RDF

ALIGNED, AKSW’s new H2020-funded project, kicked off in Dublin. The project brings together computer science researchers, companies building data-intensive systems and information technology, and academic curators of large datasets in an effort to build IT systems for aligned, co-evolving software and data lifecycles. These lifecycles will support automated testing, runtime data quality analytics, model-generated extraction and human curation interfaces.

AKSW will lead the data quality engineering part of ALIGNED, controlling the data lifecycle and providing integrity and verification techniques, using state-of-the-art tools such as RDFUnit and upcoming standards like  W3C Data Shapes. In this project, we will support our partners at Trinity College Dublin and Oxford Software Engineering as technical partners, Oxford Anthropology and Adam Mickiewicz University Poznan as data curators and publishers, as well as the Semantic Web Company and Wolters Kluwer, Germany providing enterprise solutions and use cases.

Find out more at aligned-project.eu and following @AlignedProject on Twitter.

Martin Brümmer on behalf of the NLP2RDF group

ALIGNED project kick-off

Tue, 03/03/2015 - 11:43

Categories:

RDF

ALIGNED, AKSW’s new H2020-funded project, kicked off in Dublin. The project brings together computer science researchers, companies building data-intensive systems and information technology, and academic curators of large datasets in an effort to build IT systems for aligned, co-evolving software and data lifecycles. These lifecycles will support automated testing, runtime data quality analytics, model-generated extraction and human curation interfaces.

AKSW will lead the data quality engineering part of ALIGNED, controlling the data lifecycle and providing integrity and verification techniques, using state-of-the-art tools such as RDFUnit and upcoming standards like  W3C Data Shapes. In this project, we will support our partners at Trinity College Dublin and Oxford Software Engineering as technical partners, Oxford Anthropology and Adam Mickiewicz University Poznan as data curators and publishers, as well as the Semantic Web Company and Wolters Kluwer, Germany providing enterprise solutions and use cases.

Find out more at aligned-project.eu and following @AlignedProject on Twitter.

Martin Brümmer on behalf of the NLP2RDF group

AKSW Colloquium: Tommaso Soru and Martin Brümmer on Monday, March 2 at 3.00 p.m.

Fri, 02/27/2015 - 12:57

Categories:

RDF

On Monday, 2nd of March 2015, Tommaso Soru will present ROCKER, a refinement operator approach for key discovery. Martin Brümmer will then present NIF annotation and provenance – A comparison of approaches.

Tommaso Soru – ROCKER – Abstract

As within the typical entity-relationship model, unique and composite keys are of central importance also when their concept is applied on the Linked Data paradigm. They can provide help in manifold areas, such as entity search, question answering, data integration and link discovery. However, the current state of the art does not count approaches able to scale while relying on a correct definition of key. We thus present a refinement-operator-based approach dubbed ROCKER, which has shown to scale to big datasets with respect to the run time and the memory consumption. ROCKER will be officially introduced at the 24th International Conference on World Wide Web.

Tommaso Soru, Edgard Marx, and Axel-Cyrille Ngonga Ngomo, “ROCKER – A Refinement Operator for Key Discovery”. [PDF]

Martin Brümmer – Abstract – NIF annotation and provenance – A comparison of approaches

The uptaking use of the NLP Interchange Format (NIF) reveals its shortcomings on a number of levels. One of these is tracking metadata of annotations represented in NIF – which NLP tool added which annotation with what confidence at which point in time etc.

A number of solutions to this task of annotating annotations expressed as RDF statements has been proposed over the years. The talk will weigh these solutions, namely annotation resources, reification, Open Annotation, quads and singleton properties in regard to their granularity, ease of implementation and query complexity.

The goal of the talk is presenting and comparing viable alternatives of solving the problem at hand and collecting feedback on how to proceed.

AKSW Colloquium: Tommaso Soru and Martin Brümmer on Monday, March 2 at 3.00 p.m.

Fri, 02/27/2015 - 12:57

Categories:

RDF

On Monday, 2nd of March 2015, Tommaso Soru will present ROCKER, a refinement operator approach for key discovery. Martin Brümmer will then present NIF annotation and provenance – A comparison of approaches.

Tommaso Soru – ROCKER – Abstract

As within the typical entity-relationship model, unique and composite keys are of central importance also when their concept is applied on the Linked Data paradigm. They can provide help in manifold areas, such as entity search, question answering, data integration and link discovery. However, the current state of the art does not count approaches able to scale while relying on a correct definition of key. We thus present a refinement-operator-based approach dubbed ROCKER, which has shown to scale to big datasets with respect to the run time and the memory consumption. ROCKER will be officially introduced at the 24th International Conference on World Wide Web.

Tommaso Soru, Edgard Marx, and Axel-Cyrille Ngonga Ngomo, “ROCKER – A Refinement Operator for Key Discovery”. [PDF]

Martin Brümmer - Abstract – NIF annotation and provenance – A comparison of approaches

The uptaking use of the NLP Interchange Format (NIF) reveals its shortcomings on a number of levels. One of these is tracking metadata of annotations represented in NIF – which NLP tool added which annotation with what confidence at which point in time etc.

A number of solutions to this task of annotating annotations expressed as RDF statements has been proposed over the years. The talk will weigh these solutions, namely annotation resources, reification, Open Annotation, quads and singleton properties in regard to their granularity, ease of implementation and query complexity.

The goal of the talk is presenting and comparing viable alternatives of solving the problem at hand and collecting feedback on how to proceed.

Open Data Standards

Thu, 02/26/2015 - 16:34

Categories:

RDF
Data on the Web Best Practices WG co-chair Steve Adler writes: Yesterday, Open Data reached a new milestone with the publication of the W3C’s first public working draft of its Data on the Web Best Practices. Open Data is spreading … Continue reading →

DC-2015 Professional Program Session in Portuguese & English

Mon, 02/23/2015 - 23:59

Categories:

RDF
2015-02-23, DCMI and the DC-2015 host, São Paulo State University, are please to announce that session proposals as well as the presentation language of sessions in the Professional Program at DC-2015 may be in either Portuguese or English. Depending on the language of the session presenters, simultaneous English/Portuguese or Portuguese/English translation will be provided. Tracks in the Professional Program include special topic sessions and panels, half- and full-day tutorials, workshops, and best practice posters and demonstrations.The call for participation in both the Professional and Technical Programs remain open until 28 March 2015. The call for participation can be found at http://purl.org/dcevents/dc-2015/cfp.