AKSW Colloquium, 12 October, 3pm, A High Performance Approach to String Distance using Most Frequent K Characters

Posted on October 12, 2015 by Andre Valdestilhas

Andre Valdestilhas will present the current state of his work “A High Performance Approach to String Distance using Most Frequent K Characters”.

Abstract

The idea is to reduce the computation in Link Discovery using and improving a String Distance Function called Most Frequent K Characters in order to get the Euclidean distance between two strings with a high performance. In order to do that we did experiments implementing a threshold and filters that allow skip cases when the distance between two strings are so much that no need to do a the whole computation. Also, we did experiments with parallel and GPU, also with a performance gain.

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.

Posted in Colloquium | Comments Off on AKSW Colloquium, 12 October, 3pm, A High Performance Approach to String Distance using Most Frequent K Characters

AKSW Colloquium, 28 September, 3pm, Overcoming Challenges of Question Answering in the Semantic Web

Posted on September 28, 2015 by MohamedSherif

Konrad Höffner will present the current state of the survey “Overcoming Challenges of Question Answering in the Semantic Web”, which will be submitted to the Semantic Web Journal. It is a joined work with the QA experts in the group and a researcher from Uni Bielefeld. The survey will form the related work chapter of his thesis.

Abstract

Semantic Question Answering (SQA) removes two major access requirements to the Semantic Web: the mastery of a formal query language like SPARQL and knowledge of a specific vocabulary. Because of the complexity of natural language, SQA presents difficult challenges and many research opportunities. Instead of a shared effort, however, many essential components are redeveloped, which is an inefficient use of researcher’s time. This survey analyzes 62 different SQA systems, which are systematically and manually selected using predefined inclusion and exclusion criteria, leading to 72 selected publications out of 1960 candidates. We identify common challenges, structure solutions, and provide recommendations for future systems. This work, based on publications from the end of 2010 to July 2015, is also compared to older, similar surveys.

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.

Posted in Colloquium | Comments Off on AKSW Colloquium, 28 September, 3pm, Overcoming Challenges of Question Answering in the Semantic Web

AKSW Colloquium, 21 September, 3pm, An Open Question Answering Framework

Posted on September 20, 2015 by EdgardMarx

This Colloquium will be presented by Edgard Marx and Diego Moussallem.

Edgard MarxEdgard Marx will present the progress of his PhD titled “An Open Question Answering Framework”. Billions of facts pertaining to a multitude of domains are now available on the Web as RDF data. However, accessing this data is still a difficult endeavour for non-expert users. The goal of this PhD is the development of a framework for Question Answering over Linked Data.

 

Edgard MarxDiego Moussallem will present a survey about machine translation using semantic web technologies as well as his future works. Although Machine Translation systems have achieved significant results int the last decade, there are still space for improvement. One of the main challenges in Machine Translation is the ambiguity. However, the use of semantic web technologies can overcome this obstacles.

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.

Posted in Colloquium | Comments Off on AKSW Colloquium, 21 September, 3pm, An Open Question Answering Framework

AKSW Colloquium, 14 September, 3pm, Learning Metrics for Link Discovery

Posted on September 13, 2015 by TommasoSoru

Tommaso SoruIn this Colloquium, Tommaso Soru will present the progress of his PhD titled “Learning Metrics for Link Discovery”. The discovery of new links is essential for the construction of the Linked Data cloud. The use of links to other URIs was initially suggested by Tim Berners-Lee and is known as the 4th Linked Data Principle. The goal of this PhD is to research new approaches based on machine- and statistical-learning techniques for Link Discovery.

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.

Posted in Colloquium, LIMES, PHD progress report, PhD topic | Tagged , , | Comments Off on AKSW Colloquium, 14 September, 3pm, Learning Metrics for Link Discovery

AKSW Colloquium, 7 September, 3pm, Practice Talks

Posted on September 7, 2015 by Claus Stadler

Afterwards, Claus Stadler will give a practice talk on Unsupervised Learning of an Extensive and Usable Taxonomy for DBpedia on behalf of Marco Fossati, Dimitris Kontokostas and Jens Lehmann.

ABSTRACT: In the digital era, Wikipedia represents a comprehensive cross-domain source of knowledge with millions of contributors. The DBpedia project transforms Wikipedia content into RDF and currently plays a crucial role in the Web of Data as a central multilingual interlinking hub. However, its main classification system depends on human curation, which causes it to lack coverage, resulting in a large amount of untyped resources. We present an unsupervised approach that automatically learns a taxonomy from the Wikipedia category system and extensively assigns types to DBpedia entities, through the combination of several interdisciplinary techniques. It provides a robust backbone for DBpedia knowledge and has the benefit of being easy to understand for end users. Crowdsourced online evaluations demonstrate that our strategy outperforms state-of-the-art approaches both in terms of coverage and intuitiveness.

 

 

Posted in Colloquium, paper presentation | Comments Off on AKSW Colloquium, 7 September, 3pm, Practice Talks

AKSW Colloquium, 31 August, 3pm, Dockerizing Linked Data

Posted on September 1, 2015 by NatanaelArndt

In this colloquium, Natanael Arndt will present his paper “Knowledge Base Shipping to the Linked Open Data Cloud“.

Abstract: Popular knowledge bases that provide SPARQL endpoints for the web are usually experiencing a high number of requests, which often results in low availability of their interfaces. A common approach to counter the availability issue is to run a local mirror of the knowledge base. Running a SPARQL endpoint is currently a complex task which requires a lot of effort and technical support for domain experts who just want to use the SPARQL interface. With our approach of containerised knowledge base shipping we are introducing a simple to setup methodology for running a local mirror of an RDF knowledge base and SPARQL endpoint with interchangeable exploration components. The flexibility of the presented approach further helps maintaining the publication infrastructure for dataset projects. We are demonstrating and evaluating the presented methodology at the example of the dataset projects DBpedia, Catalogus Professorum Lipsiensium and Sächsisches Pfarrerbuch.

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.

Posted in Colloquium, paper presentation | Comments Off on AKSW Colloquium, 31 August, 3pm, Dockerizing Linked Data

AKSW Colloquium, 24 August, 3pm, Lucene, SOLR, FEASIBLE

Posted on August 24, 2015 by AmrapaliZaveri

In this colloquium, first, Kay Müller and Nilesh Chakraborty will give an overview of Lucene and SOLR and how they can be used in information retrieval scenarios, along with a short peek into ElasticSearch, introducing a few recent features, their respective use-cases and how they compare with SOLR.

Then, Muhammed Saleem will present his paper “FEASIBLE: A Featured-Based SPARQL Benchmark Generation Framework“

Abstract: Benchmarking is indispensable when aiming to assess technologies with respect to their suitability for given tasks. While several benchmarks and benchmark generation frameworks have been developed to evaluate triple stores, they mostly provide a one-fits-all solution to the benchmarking problem. This approach to benchmarking is however unsuitable to evaluate the performance of a triple store for a given application with particular requirements. We address this drawback by presenting FEASIBLE, an automatic approach for the generation of benchmarks out of the query history of applications, i.e., query logs. The generation is achieved by selecting prototypical queries of a user-defined size from the input set of queries. We evaluate our approach on two query logs and show that the benchmarks it generates are accurate approximations of the input query logs. Moreover, we compare four different triple stores with benchmarks generated using our approach and show that they behave differently based on the data they contain and the types of queries posed. Our results suggest that FEASIBLE generates better sample queries than the state of the art. In addition, the better query selection and the larger set of query types used lead to triple store rankings which partly differ from the rankings generated by previous works.

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.

Posted in Announcements, Colloquium, Events | Comments Off on AKSW Colloquium, 24 August, 3pm, Lucene, SOLR, FEASIBLE

AKSW has 10 accepted publications in Semantics’2015 conference

Posted on August 18, 2015 by Ivan Ermilov

The Semantics‘2015 conference will take place in Vienna, Austria on September 15-17, 2015. AKSW is happy to announce 10 accepted publications: 6 for research track and 4 for demos/posters track. Semantics’2015 has received 93 submissions for research track, out of which 24 were accepted (an acceptance rate of 26%).

For the research track our accepted papers are:

For the poster/demo track:

See you at the conference in September!

Posted in Papers | Comments Off on AKSW has 10 accepted publications in Semantics’2015 conference

AKSW Colloquium, 17-08-2015, Relational Machine Learning for Knowledge Graphs, Zoo Keeper, Apache Mesos

Posted on August 17, 2015 by Patrick Westphal

Relational Machine Learning for Knowledge Graphs

In this colloquium Patrick Westphal will present the paper “A Review of Relational Machine Learning for Knowledge Graphs” by Nickel, Murphy, Tresp and Gabrilovich.

Abstract: Relational machine learning studies methods for the statistical analysis of relational, or graph-structured, data. In this paper, we provide a review of how such statistical models can be “trained” on large knowledge graphs, and then used to predict new facts about the world (which is equivalent to predicting new edges in the graph). In particular, we discuss two different kinds of statistical relational models, both of which can scale to massive datasets. The first is based on tensor factorization methods and related latent variable models. The second is based on mining observable patterns in the graph. We also show how to combine these latent and observable models to get improved modeling power at decreased computational cost. Finally, we discuss how such statistical models of graphs can be combined with text-based information extraction methods for automatically constructing knowledge graphs from the Web. In particular, we discuss Google’s Knowledge Vault project.

Zoo Keeper, Apache Mesos

A short introduction to the coordination system ‘ZooKeeper’ and cluster manager ‘Apache Mesos’ will be presented by Hajira.
Mesos provides efficient resource isolation and sharing across distributed applications and frameworks. It can run a multitude of applications on a dynamically shared pool of resources being coordinated by zookeeper.

Posted in Colloquium, Uncategorized | Comments Off on AKSW Colloquium, 17-08-2015, Relational Machine Learning for Knowledge Graphs, Zoo Keeper, Apache Mesos

18 AKSW Papers at ISWC 2015

Posted on August 12, 2015 by Muhammad Saleem

logoWe are very pleased to announce that AKSW will be presenting 18 papers in the upcoming International Semantic Web Conference (ISWC) 2015.  Following are the details:

Research track:

  1. TITLE: FEASIBLE: A Featured-Based SPARQL Benchmarks Generation Framework
    AUTHORS: Muhammad Saleem, Qaiser Mehmood, Axel-Cyrille Ngonga Ngomo
  2. TITLE: LANCE: Piercing to the Heart of Instance Matching Tools
    AUTHORS: Tzanina Saveta, Evangelia Daskalaki, Giorgos Flouris, Irini Fundulaki, Melanie Herschel, Axel-Cyrille Ngonga Ngomo

  In-Use and Software track: 

  1. TITLE: ASSESS —Automatic Self-Assessment Using Linked Data
    AUTHORS: Lorenz Bühmann, Ricardo Usbeck,  Axel-Cyrille Ngonga Ngomo 
  2. TITLE: Assessing and Refining Mappings to RDF to Improve Data Quality
    AUTHORS: Anastasia Dimou, Dimitris Kontokostas, Markus Freudenberg, Ruben Verborgh, Jens Lehmann, Erik Mannens, Sebastian Hellmann, Rik Van de Walle

  Data Sets and Ontologies: 

  1. TITLE: LSQ: Linked SPARQL Queries Dataset
    AUTHORS: Muhammad Saleem, Muhammad Intizar Ali, Aidan Hogan, Qaiser Mehmood, Axel-Cyrille Ngonga Ngomo
  2. TITLE: DBpedia Commons: Structured Multimedia Metadata for Wikimedia Commons
    AUTHORS: Gaurav Vaidya, Dimitris Kontokostas, Magnus Knuth, Jens Lehmann, Sebastian Hellmann

  Posters and Demos: 

  1. TITLE: Enhancing Dataset Quality Using Keys          [demo]
    AUTHORS: Tommaso Soru, Edgard Marx, Axel-Cyrille Ngonga Ngomo
  2. TITLE: The DBpedia Events Dataset          [demo]
    AUTHORS: Magnus Knuth, Jens Lehmann, Dimitris Kontokostas, Thomas Steiner, Harald Sack
  3. TITLE: Test-driven Assessment of [R2]RML Mappings to Improve Dataset Quality
    AUTHORS: Anastasia Dimou, Dimitris Kontokostas, Markus Freudenberg, Ruben Verborgh, Jens Lehmann, Erik Mannens, Sebastian Hellmann, Rik Van de Walle
  4. TITLE: Interoperable Machine Learning Metadata using MEX          [demo]
    AUTHORS: Diego Esteves, Diego Moussallem, Jens Lehmann, Maria Claudia, J.Cesar Duarte
  5. TITLE: Automatic SPARQL Benchmark Generation Using FEASIBLE          [demo]
    AUTHORS: Muhammad Saleem, Qaiser Mehmood, Axel-Cyrille Ngonga Ngomo
  6. TITLE: The LSQ Dataset: Querying for Queries          [demo]
    AUTHORS: Muhammad Saleem, Muhammad Intizar Ali, Aidan Hogan, Qaiser Mehmood, Axel-Cyrille Ngonga Ngomo
  7. TITLE: openQA: An Open-Source Question Answering Framework          [demo]
    AUTHORS: Edgard Marx, Tommaso Soru, Diego Esteves, Axel-Cyrille Ngonga Ngomo, Jens Lehmann 
  8. TITLE: LANCE: A Generic Benchmark Generator for Linked Data
    AUTHORS: Tzanina Saveta, Evangelia Daskalaki, Giorgos Flouris, Irini Fundulaki, Melanie Herschel, Axel-Cyrille Ngonga Ngomo
  9. TITLE: SPARQL Query Formulation and Execution using FedViz          [demo]
    AUTHORS: Syeda Sana e Zainab, Ali Hasnain, Muhammad Saleem, Qaiser Mehmood, Durre Zehra, Stefan Decker

  Workshops: 

  1. TITLE: FedViz: A Visual Interface for SPARQL Queries Formulation and Execution
    AUTHORS: Syeda Sana e Zainab, Ali Hasnain, Muhammad Saleem, Qaiser Mehmood, Durre Zehra, Stefan Decker
  2. TITLE: Answering Boolean Hybrid Questions with HAWK
    AUTHORS: Ricardo Usbeck, Erik Körner,  Axel-Cyrille Ngonga Ngomo

  Tutorial: 

TITLE: Federated Query Processing over Linked Data
AUTHORS: Muhammad Saleem, Muhammad Intizar Ali, Ruben Verborgh, Axel-Cyrille Ngonga Ngomo

 

Come over to ISWC 2015 and enjoy the talks.

Best Regards,
Saleem on behalf of AKSW

Posted in Announcements, Papers | Tagged , | Comments Off on 18 AKSW Papers at ISWC 2015