1 code implementation • ACL (WebNLG, INLG) 2020 • Diego Moussallem, Paramjot Kaur, Thiago Ferreira, Chris van der Lee, Anastasia Shimorina, Felix Conrads, Michael Röder, René Speck, Claire Gardent, Simon Mille, Nikolai Ilinykh, Axel-Cyrille Ngonga Ngomo
The RDF-to-text task has recently gained substantial attention due to the continuous growth of RDF knowledge graphs in number and size.
1 code implementation • COLING 2022 • Alexander Bondarenko, Magdalena Wolska, Stefan Heindorf, Lukas Blübaum, Axel-Cyrille Ngonga Ngomo, Benno Stein, Pavel Braslavski, Matthias Hagen, Martin Potthast
At least 5% of questions submitted to search engines ask about cause-effect relationships in some way.
1 code implementation • 23 Oct 2023 • N'Dah Jean Kouagou, Caglar Demir, Hamada M. Zahera, Adrian Wilke, Stefan Heindorf, Jiayi Li, Axel-Cyrille Ngonga Ngomo
Most of them obtain embeddings by learning the structure of the knowledge graph within a link prediction setting.
1 code implementation • 16 Jun 2023 • Pere-Lluís Huguet Cabot, Simone Tedeschi, Axel-Cyrille Ngonga Ngomo, Roberto Navigli
Relation Extraction (RE) is a task that identifies relationships between entities in a text, enabling the acquisition of relational facts and bridging the gap between natural language and structured knowledge.
1 code implementation • 28 Apr 2023 • Caglar Demir, Michel Wiebesiek, Renzhong Lu, Axel-Cyrille Ngonga Ngomo, Stefan Heindorf
We evaluate LitCQD on query types with and without literal values.
1 code implementation • 3 Mar 2023 • Caglar Demir, Axel-Cyrille Ngonga Ngomo
We reformulate the learning problem as a multi-label classification problem and propose a neural embedding model (NERO) that learns permutation-invariant embeddings for sets of examples tailored towards predicting $F_1$ scores of pre-selected description logic concepts.
no code implementations • 12 Jan 2023 • Leonie Nora Sieger, Stefan Heindorf, Yasir Mahmood, Lukas Blübaum, Axel-Cyrille Ngonga Ngomo
Knowledge bases are widely used for information management, enabling high-impact applications such as web search, question answering, and natural language processing.
1 code implementation • 18 Jul 2022 • Caglar Demir, Axel-Cyrille Ngonga Ngomo
Knowledge graph embedding research has mainly focused on learning continuous representations of knowledge graphs towards the link prediction problem.
1 code implementation • 13 May 2022 • Caglar Demir, Julian Lienen, Axel-Cyrille Ngonga Ngomo
Our experiments suggest that applying Kronecker decomposition on embedding matrices leads to an improved parameter efficiency on all benchmark datasets.
no code implementations • 7 Dec 2021 • Nandana Mihindukulasooriya, Mohnish Dubey, Alfio Gliozzo, Jens Lehmann, Axel-Cyrille Ngonga Ngomo, Ricardo Usbeck, Gaetano Rossiello, Uttam Kumar
The Semantic Answer Type and Relation Prediction Task (SMART) task is one of the ISWC 2021 Semantic Web challenges.
no code implementations • 16 Nov 2021 • N'Dah Jean Kouagou, Stefan Heindorf, Caglar Demir, Axel-Cyrille Ngonga Ngomo
Our main intuition is that class expression learning can be regarded as a translation problem.
1 code implementation • 8 Nov 2021 • Stefan Heindorf, Lukas Blübaum, Nick Düsterhus, Till Werner, Varun Nandkumar Golani, Caglar Demir, Axel-Cyrille Ngonga Ngomo
We contribute a novel initialization method for the initial population: starting from positive examples, we perform biased random walks and translate them to description logic concepts.
1 code implementation • 10 Jul 2021 • N'Dah Jean Kouagou, Stefan Heindorf, Caglar Demir, Axel-Cyrille Ngonga Ngomo
We then extend the CELOE algorithm, which learns ALC concepts, with our concept length predictor.
1 code implementation • 29 Jun 2021 • Caglar Demir, Diego Moussallem, Stefan Heindorf, Axel-Cyrille Ngonga Ngomo
We propose the four approaches QMult, OMult, ConvQ and ConvO to tackle the link prediction problem.
1 code implementation • 29 Jun 2021 • Caglar Demir, Axel-Cyrille Ngonga Ngomo
In this work, we leverage deep reinforcement learning to accelerate the learning of concepts in $\mathcal{ALC}$ by proposing DRILL -- a novel class expression learning approach that uses a convolutional deep Q-learning model to steer its search.
1 code implementation • 26 May 2021 • Caglar Demir, Axel-Cyrille Ngonga Ngomo
As benchmarks are crucial for the fair comparison of algorithms, ensuring their quality is tantamount to providing a solid ground for developing better solutions to link prediction and ipso facto embedding knowledge graphs.
no code implementations • 18 Apr 2021 • Moemmur Shahzad, Ayesha Amin, Diego Esteves, Axel-Cyrille Ngonga Ngomo
Our model outperforms the current state of the art on various NER datasets.
Ranked #5 on Named Entity Recognition (NER) on WNUT 2016
1 code implementation • 2 Apr 2021 • Umair Qudus, Muhammad Saleem, Axel-Cyrille Ngonga Ngomo, Young-Koo Lee
Albeit informative, these metrics are generic and unable to quantify and evaluate the accuracy of the cardinality estimators of cost-based federation engines.
1 code implementation • 11 Mar 2021 • Daniel Vollmers, Rricha Jalota, Diego Moussallem, Hardik Topiwala, Axel-Cyrille Ngonga Ngomo, Ricardo Usbeck
In this paper, we present a novel QA approach, dubbed TeBaQA.
no code implementations • 25 Feb 2021 • Waqas Ali, Muhammad Saleem, Bin Yao, Aidan Hogan, Axel-Cyrille Ngonga Ngomo
RDF has seen increased adoption in recent years, prompting the standardization of the SPARQL query language for RDF, and the development of local and distributed engines for processing SPARQL queries.
Knowledge Graphs Databases
1 code implementation • 22 Jan 2021 • Caglar Demir, Diego Moussallem, Axel-Cyrille Ngonga Ngomo
We predict missing triples via the relation prediction.
1 code implementation • 1 Dec 2020 • Nandana Mihindukulasooriya, Mohnish Dubey, Alfio Gliozzo, Jens Lehmann, Axel-Cyrille Ngonga Ngomo, Ricardo Usbeck
Each year the International Semantic Web Conference accepts a set of Semantic Web Challenges to establish competitions that will advance the state of the art solutions in any given problem domain.
no code implementations • 16 Sep 2020 • Diego Moussallem, Dwaraknath Gnaneshwar, Thiago castro Ferreira, Axel-Cyrille Ngonga Ngomo
The RDF-to-text task has recently gained substantial attention due to continuous growth of Linked Data.
1 code implementation • 13 Sep 2020 • Xinyue Zhang, Meng Wang, Muhammad Saleem, Axel-Cyrille Ngonga Ngomo, Guilin Qi, Haofen Wang
Based on Semantic Web technologies, knowledge graphs help users to discover information of interest by using live SPARQL services.
1 code implementation • 7 Aug 2020 • Caglar Demir, Axel-Cyrille Ngonga Ngomo
In this paper, we study the problem of learning continuous vector representations of knowledge graphs for predicting missing links.
1 code implementation • 3 Apr 2020 • Ram G Athreya, Srividya Bansal, Axel-Cyrille Ngonga Ngomo, Ricardo Usbeck
When the top-2 most likely templates were considered the model achieves an accuracy of 0. 945 on the LC-QuAD dataset and 0. 786 on the QALD-7 dataset.
2 code implementations • 4 Mar 2020 • Aidan Hogan, Eva Blomqvist, Michael Cochez, Claudia d'Amato, Gerard de Melo, Claudio Gutierrez, José Emilio Labra Gayo, Sabrina Kirrane, Sebastian Neumaier, Axel Polleres, Roberto Navigli, Axel-Cyrille Ngonga Ngomo, Sabbir M. Rashid, Anisa Rula, Lukas Schmelzeisen, Juan Sequeda, Steffen Staab, Antoine Zimmermann
In this paper we provide a comprehensive introduction to knowledge graphs, which have recently garnered significant attention from both industry and academia in scenarios that require exploiting diverse, dynamic, large-scale collections of data.
1 code implementation • 21 Jan 2020 • Caglar Demir, Axel-Cyrille Ngonga Ngomo
We present a novel and scalable paradigm for the computation of knowledge graph embeddings, which we dub PYKE .
1 code implementation • 17 Dec 2019 • Michael Röder, Geraldo de Souza, Denis Kuchelev, Abdelmoneim Amer Desouki, Axel-Cyrille Ngonga Ngomo
Although Data Web crawlers exist, and general Web crawlers could be adapted to focus on the Data Web, there is currently no benchmark to fairly evaluate their performance.
Databases Performance
no code implementations • 19 Nov 2019 • Abdullah Fathi Ahmed, Mohamed Ahmed Sherif, Axel-Cyrille Ngonga Ngomo
Complex LS com- bine similarity measures with thresholds to determine whether a given predicate holds between two resources.
no code implementations • RANLP 2019 • Axel-Cyrille Ngonga Ngomo, Diego Moussallem, Lorenz Bühmann
With the ever-growing generation of data for the Semantic Web comes an increasing demand for this data to be made available to non-semantic Web experts.
no code implementations • 23 Jul 2019 • Diego Moussallem, Matthias Wauer, Axel-Cyrille Ngonga Ngomo
Moreover, our research suggests that while Semantic Web technologies can enhance the quality of machine translation outputs for various problems, the combination of both is still in its infancy.
1 code implementation • 23 Feb 2019 • Diego Moussallem, Mihael Arčan, Axel-Cyrille Ngonga Ngomo, Paul Buitelaar
While neural networks have been used extensively to make substantial progress in the machine translation task, they are known for being heavily dependent on the availability of large amounts of training data.
1 code implementation • European Semantic Web Conference 2018 • Andre Valdestilhas, Tommaso Soru, Markus Nentwig, Edgard Marx, Muhammad Saleem, Axel-Cyrille Ngonga Ngomo
One of the Semantic Web foundations is the possibility to dereference URIs to let applications negotiate their semantic content.
1 code implementation • 29 May 2018 • Diego Moussallem, Ricardo Usbeck, Michael Röder, Axel-Cyrille Ngonga Ngomo
A plethora of Entity Linking (EL) approaches has recently been developed.
1 code implementation • LREC 2018 • Diego Moussallem, Thiago castro Ferreira, Marcos Zampieri, Maria Claudia Cavalcanti, Geraldo Xexéo, Mariana Neves, Axel-Cyrille Ngonga Ngomo
The generation of natural language from Resource Description Framework (RDF) data has recently gained significant attention due to the continuous growth of Linked Data.
1 code implementation • LREC 2018 • Diego Moussallem, Mohamed Ahmed Sherif, Diego Esteves, Marcos Zampieri, Axel-Cyrille Ngonga Ngomo
In this paper, we describe the LIDIOMS data set, a multilingual RDF representation of idioms currently containing five languages: English, German, Italian, Portuguese, and Russian.
1 code implementation • 10 Feb 2018 • Tommaso Soru, André Valdestilhas, Edgard Marx, Axel-Cyrille Ngonga Ngomo
Graph representations of large knowledge bases may comprise billions of edges.
no code implementations • 26 Nov 2017 • Diego Moussallem, Matthias Wauer, Axel-Cyrille Ngonga Ngomo
A large number of machine translation approaches have recently been developed to facilitate the fluid migration of content across languages.
1 code implementation • 3 Nov 2017 • Tommaso Soru, Diego Esteves, Edgard Marx, Axel-Cyrille Ngonga Ngomo
Markov Logic Networks join probabilistic modeling with first-order logic and have been shown to integrate well with the Semantic Web foundations.
1 code implementation • 24 Oct 2017 • Ricardo Usbeck, Michael Hoffmann, Michael Röder, Jens Lehmann, Axel-Cyrille Ngonga Ngomo
In particular, we develop a multi-label classification-based metasystem for question answering over 6 existing systems using an innovative set of 14 question features.
1 code implementation • WS 2018 • Axel-Cyrille Ngonga Ngomo, Michael Röder, Diego Moussallem, Ricardo Usbeck, René Speck
The main advantage of our benchmarks is that they can be readily generated at any time.
1 code implementation • 17 Jul 2017 • Diego Moussallem, Ricardo Usbeck, Michael Röder, Axel-Cyrille Ngonga Ngomo
Currently, the best performing approaches rely on trained mono-lingual models.
no code implementations • 1 Dec 2016 • Kleanthi Georgala, Micheal Hoffmann, Axel-Cyrille Ngonga Ngomo
Some of the most rapid Link Discovery approaches rely internally on planning to execute link specifications.
no code implementations • 6 Nov 2016 • Ricardo Usbeck, Jonathan Huthmann, Nico Duldhardt, Axel-Cyrille Ngonga Ngomo
Based on these descriptions, our approach will be able to automatically compose QA systems using a data-driven approach automatically.
no code implementations • LREC 2014 • Axel-Cyrille Ngonga Ngomo, Norman Heino, Ren{\'e} Speck, Prodromos Malakasiotis
We introduce the BIOASQ suite, a set of open-source Web tools for the creation, assessment and community-driven improvement of question answering benchmarks.