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Adding COVID information to Wikidata [article]

Andra Waagmeester, Jose Emilio Labra Gayo
Forum: Wikidata as a knowledge graph for the life sciencesValidating RDF  ...  We will describe what Shape Expressions are, how they can be used in Wikidata and explore some related tools.A protocol for adding knowledge to Wikidata: aligning resources on human coronavirusesScience  ...  identifiers ○ IRI mapping Entity schemas and Shape Expressions at Wikidata RDF and knowledge graphs, the good parts Data integration Merging RDF graphs automatically RDF as a basis for knowledge  ... 
doi:10.6084/m9.figshare.14428868.v1 fatcat:mv2kz5ntajbnheqraqqkfhnvva

RDF Repository Optimization Structure Method for Processing Context-aware of IoT Environment

Su-kyoung Kim, Sung-en Kim, Gui-hyun Baek, Kee-hong Ahn
2015 International Journal of Software Engineering and Its Applications  
This paper suggests the optimization method of RDF Repository.  ...  For this, People suggest a method such as SSNO based on ontology. However, techniques were center of modeling to express most things.  ...  Acknowledgments This work was supported by the Korea Foundation for the Advancement of Science & Creativity(KOFAC), and funded by the Korean Government(MOE).  ... 
doi:10.14257/ijseia.2015.9.12.09 fatcat:wvrabb5idrbi7ifrbhgzpcidoe

Semantic Query Routing and Processing in P2P Database Systems: The ICS-FORTH SQPeer Middleware [chapter]

George Kokkinidis, Vassilis Christophides
2004 Lecture Notes in Computer Science  
However, a fully-fledged framework for evaluating semantic queries over peer RDF/S bases (materialized or virtual) is missing.  ...  More and more P2P data management systems rely nowadays on intensional (i.e. schema) information for integrating and querying peer bases.  ...  Acknowledgment We would like to thank Val Tannen for fruitful discussions on peer channels.  ... 
doi:10.1007/978-3-540-30192-9_48 fatcat:fpr4yn7u5fhr3kwz7tyefkrydq

Reasoning on web data: Algorithms and performance

Damian Bursztyn, Francois Goasdoue, Ioana Manolescu, Alexandra Roatis
2015 2015 IEEE 31st International Conference on Data Engineering  
Our tutorial introduces the RDF ontological schema language for enhancing the RDF graphs' semantics, formalizes the query answering problem relying on reasoning, and provides a principled classification  ...  Simple RDF graphs can be seen as collections of facts, which may be further enriched with ontological schemas, or semantic constraints, based on which reasoning can be applied to infer new information.  ...  RDF and RDFS The Resource Description Framework [4] is a graph-based data model accepted as the W3C standard for Semantic Web applications.  ... 
doi:10.1109/icde.2015.7113422 dblp:conf/icde/BursztynGMR15 fatcat:dudx4plquzbebfz7w5s2ooppam


Li Ma, Zhong Su, Yue Pan, Li Zhang, Tao Liu
2004 Proceedings of the Thirteenth ACM conference on Information and knowledge management - CIKM '04  
Such analysis will be helpful for designing RDF storage and query systems as well as for understanding not well-solved issues in RDF based enterprise resource management.  ...  RStar uses a relational database as the persistent data store and defines RStar Query Language (RSQL) for resource retrieval.  ...  The authors would like to thank Bo Hu and Ming Zhao for their constructive comments and help with implementation, Zhuo Zhang, Guotong Xie and Shixia Liu for their helpful discussions.  ... 
doi:10.1145/1031171.1031264 dblp:conf/cikm/MaSPZL04 fatcat:kpuswdfyofaetbw2tjh5vxt6hi

RDFBroker: A Signature-Based High-Performance RDF Store [chapter]

Michael Sintek, Malte Kiesel
2006 Lecture Notes in Computer Science  
Our approach can be used for both in-memory and on-disk relational database-based RDF store implementations.  ...  This technique can therefore be used for arbitrary RDF data, i.e., RDF Schema or any other schema/ontology language on top of RDF is not required.  ...  Our approach can handle, on standard hardware, already fairly large knowledge bases (RDF files with several hundred MBs) in main memory.  ... 
doi:10.1007/11762256_28 fatcat:rcfejzojivfx7iyc7m2wxurgai

Selectivity Estimation for SPARQL Triple Patterns with Shape Expressions [chapter]

Abdullah Abbas, Pierre Genevès, Cécile Roisin, Nabil Layaïda
2018 Lecture Notes in Computer Science  
ShEx (Shape Expressions) is a language for expressing constraints on RDF graphs.  ...  In this work we optimize the evaluation of conjunctive SPARQL queries, on RDF graphs, by taking advantage of ShEx constraints.  ...  . method by exploiting information extracted from a ShEx schema. To the best of our knowledge, this is the first work addressing SPARQL query optimization based on ShEx.  ... 
doi:10.1007/978-3-319-91662-0_15 fatcat:tnpep777vbbvfcgqnsofpid2dm

Integrating Heterogeneous Data Source Using Ontology

Jinpeng Wang, Jianjiang Lu, Yafei Zhang, Zhuang Miao, Bo Zhou
2009 Journal of Software  
To model different data. source schemas, we propose a describing method based on y A data source describing method based on SPARQL RDF graph patterns.  ...  A source construct ontologies from relational databases schema. describing method based on RDF graph patterns is pro- This method cannot fully capture the semantic behind the posed to specify  ... 
doi:10.4304/jsw.4.8.843-850 fatcat:urepz7hsqjf6hbbrwihjqc55ae

A survey of RDF storage approaches

David C. Faye, Olivier Curé, Guillaume Blin
2012 ARIMA  
In recent years RDF has been a widespread data format for the Semantic Web.  ...  This paper gives an overview of the features of techniques for storing \textttRDF data.  ...  RDFKB [52] (Resource Description Framework Knowledge Base) is a relational database system for RDF datasets supporting OWL inference rules and knowledge management.  ... 
doi:10.46298/arima.1956 fatcat:j2zjgg4dvzhmjm7qoimwzknjc4

An Analysis of RDF Storage Models and Query Optimization Techniques

Asim Sinan Yuksel, Ibrahim Arda Cankaya, Mehmet Erkan Yuksel
2015 International Journal of Information Engineering and Electronic Business  
Resource Description Framework (RDF) is a basis for handling these metadata and is a graph-based, self-describing data format that represents information about web-based resources.  ...  Several storage techniques are discussed along with the methods for optimizing the queries for RDF datasets. We present the differences between the Relational Database and the XML technology.  ...  Based on the sub-graphs, [7] designed their relational schema that includes the relations class, property, resource, triple, path and type as shown in Fig. 5 .  ... 
doi:10.5815/ijieeb.2015.02.04 fatcat:o6c2zmu3xbg3vn6qhgyjdsu2pu

Knowledge Extraction from Structured Sources [chapter]

Jörg Unbehauen, Sebastian Hellmann, Sören Auer, Claus Stadler
2012 Lecture Notes in Computer Science  
This chapter surveys knowledge extraction approaches from structured sources such as relational databases, XML and CSV.  ...  As an example, we provide a formalization and description of SparqlMap, which implements the relational database to RDF mapping language R2RML currently being standardized by the W3C.  ...  This work was partially supported by a grant from the European Union's 7th Framework Programme provided for the project LOD2 (GA no. 257943).  ... 
doi:10.1007/978-3-642-34213-4_3 fatcat:txmhb6vgpvhhxhluad66efalza

Relational processing of RDF queries

Sherif Sakr, Ghazi Al-Naymat
2010 SIGMOD record  
This survey focuses on using relational query processors to store and query RDF data.  ...  The Resource Description Framework (RDF) is a flexible model for representing information about resources in the web.  ...  [18] have proposed a path-based relational RDF database.  ... 
doi:10.1145/1815948.1815953 fatcat:yhobpplevzdjvnbfqgpciyzsx4

Teaching Learning Based Optimization in Semantic Web of Distributed RDF

2019 International journal of recent technology and engineering  
In this research, the Teacher Learning based Optimization (TLBO) algorithm is proposed for the query optimization to reduce query cost, and optimize the computation time of the query.  ...  The TLBO technique select the suitable location and size of the population based on the data that effectively provide the solution for the distributed data i.e.., triple pattern of semantic web.  ...  RDF Schema provides key features like property, sub-property, class, subclass relations, range restrictions and domain.  ... 
doi:10.35940/ijrte.b3191.078219 fatcat:fjikl576r5foxmwwtckm6fpzd4

MedTQ: Dynamic Topic Discovery and Query Generation for Medical Ontologies [article]

Feichen Shen, Yugyung Lee
2018 arXiv   pre-print
A predicate neighborhood pattern-based approach introduced has the ability to compute the similarity of predicates (relations) in ontologies.  ...  In the hierarchical K-Means algorithm, a level-by-level optimization strategy was selected for consistent with the strongly association between elements within a topic.  ...  Definition 2: Given predicates and in a directed RDF schema Graph ( , ).  ... 
arXiv:1802.03855v1 fatcat:t43bswh3ozgpdfgjfip7aqxwvy

Statistics of Knowledge Graphs Based On The Conceptual Schema [article]

Iztok Savnik, Kiyoshi Nitta, Riste Skrekovski, Nikolaus Augsten
2021 arXiv   pre-print
In this paper, we propose a new approach for the computation of the statistics of knowledge graphs.  ...  Furthermore, we propose an algorithm in which the size of the schema graph can be controlled – it is based on the n levels from the upper part of the schema graph.  ...  Conceptual schema of a knowledge graph The formal definition of the schema of a knowledge graph is based on the RDF [27] and RDF-Schema [28] data models.  ... 
arXiv:2109.09391v1 fatcat:likt2tedubgs3ks2mopdzddx2y
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