The authors propose a new method for mining sets of patterns for classification, where patterns are represented as SPARQL queries over RDFS. The method contributes to so-called semantic data mining, a data mining approach where domain ontologies are used as background knowledge, and where the new challenge is to mine knowledge encoded in domain ontologies, rather than only purely empirical data...

RDF is the common data model to publish structured data on the Web. RDF data sets are given as subject-predicateobject triples and typically are represented as directed edgelabeled graphs. To make the information represented by such graphs comprehensible, RDF-schema (RDFS) provides concepts to define a class-structure as part of the given RDFgraph and thus supports a more abstract view on the d...

In the last years, a large number of RDF data sets has become available on the Web. However, due to the semi-structured nature of RDF data, missing values affect answer completeness of queries that are posed against this data. To overcome this limitation, we propose RDF-Hunter, a novel hybrid query processing approach that brings together machine and human computation to execute queries against...

A standard model for exposing structured provenance metadata of scientific assertions on the Semantic Web would increase interoperability, discoverability, reliability, as well as reproducibility for scientific discourse and evidence-based knowledge discovery. Several Resource Description Framework (RDF) models have been proposed to track provenance. However, provenance metadata may not only be...

Large-scale RDF graph databases stored in shared-nothing clusters require query processing engine that can effectively exploit highly parallel computation environment. We propose algebra of RDF graphs and its physical counterpart, physical algebra of RDF graphs, designed to implement queries as distributed dataflow programs that run on cluster of servers. Operations of algebra reflect the chara...

Both the notion of Property Graphs (PG) and the Resource Description Framework (RDF) are commonly used models for representing graph-shaped data. While there exist some systemspecific solutions to convert data from one model to the other, these solutions are not entirely compatible with one another and none of them appears to be based on a formal foundation. In fact, for the PG model, there doe...

In this paper, we present a multi-temporal RDF data model, which can be used to support RDF(S) light-weight ontology versioning. The data model is equipped with ontology change operations, which are defined in terms of low-level updates acting on RDF triples. As a result, the operational semantics of a complete set of primitive ontology changes has been formalized, taking care of preservation o...

protecting the environment is becoming one of the most important concerns of the developed and developing countries. reclamation of msw landfills, which are sources of many pollutants including leachate and greenhouse gases, would be very valuable in saving the resources and reducing the pollution scale. in the current article the potential for use of reclaimed waste in rdf production has been ...

Nowadays, the RDF data model is a crucial part of the Semantic Web. Especially web developers favour RDF serialization formats like RDFa and JSON-LD. However, the visualization of large portions of RDF data in an appealing way is still a cumbersome task. RDF visualizers in general are not targeting the Web as usage scenario or simply display the complex RDF graph directly rather than applying a...