Search results for "computer.file_format"
showing 10 items of 214 documents
An MDE Approach for Rapid Prototyping and Implementation of Dynamic Reconfigurable Systems
2015
This article presents a co-design methodology based on RecoMARTE, an extension to the well-known UML MARTE profile, which is used for the specification and automatic generation of Dynamic and Partially Reconfigurable Systems-on-Chip (DRSoC). This endeavor is part of a larger framework in which Model-Driven Engineering (MDE) techniques are extensively used for modeling and via model transformations, generating executable models, which are exploited by implementation tools to create reconfigurable systems. More specifically, the methodological aspects presented in this article are concerned with expediting the conception and implementation of the hardware platform and the integration of corre…
Schema-Based Visual Queries over Linked Data Endpoints
2019
We present the option to use the schema-based visual query tool ViziQuer over realistic Linked Data endpoints. We describe the tool meta-schema structure and the means for the endpoint schema retrieval both from an OWL ontology and from a SPARQL endpoint. We report on a store of the endpoint-specific schemas and the options to support the schema presentation to the end-user both as a class tree within the environment and as external visual diagram.
Export of Relational Databases to RDF Databases: A Case Study
2010
The vast amount of business information nowadays is stored in relational databases. For the Semantic Web vision to become a reality, we need ways how to exploit this data in form of RDF triples. The universal and commonly accepted solution for this problem still does not exist. In most cases, mapping languages are used for specification of correspondences between OWL ontology and DB schema. At the same time, these languages generally are not well suited for specification of mappings in cases when there is a substantial difference between OWL ontology and DB schema. In this paper, we describe a new model transformation-based method for specification of correspondences between the elements of…
Faceted Search Over RDF-Based Knowledge Graphs
2016
Knowledge graphs such as Yago and Freebase have become a powerful asset for enhancing search, and are being intensively used in both academia and industry. Many existing knowledge graphs are either available as Linked Open Data, or they can be exported as RDF datasets enhanced with background knowledge in the form of an OWL 2 ontology. Faceted search is the de facto approach for exploratory search in many online applications, and has been recently proposed as a suitable paradigm for querying RDF repositories. In this paper, we provide rigorous theoretical underpinnings for faceted search in the context of RDFbased knowledge graphs enhanced with OWL 2 ontologies. We identify well-defined fra…
The Anatomy of an Optical Biopsy Semantic Retrieval System
2012
A case-based computer-aided diagnosis system assists physicians and other medical personnel in the interpretation of optical biopsies obtained through confocal laser endomicroscopy. Extraction in CLE images shows promising results on inferring semantic metadata from low-level features. In order to effectively ensure the interoperability with potential third-party applications, the system provides an interface compliant with the recent standards ISO/IEC 15938-12:2008 (MPEG Query Format) and ISO/IEC 24800 (JPEG Search).
A framework for context-sensitive metadata description
2006
Expectations regarding the new generation of Web depend on the success of Semantic Web technology. Resource Description Framework (RDF) is a basis for explicit and machine-readable representation of semantics. However RDF is not suitable for describing dynamic and context-sensitive resources (eg. processes). We present the Context Description Framework (CDF) as an extension of the RDF by adding a 'TrueInContext' component to the basic RDF triple ('subject-predicate-object'), and consider contextual value as a container of RDF statements. We also add a probabilistic component, which allows multilevel contextual dependence descriptions as well as presumes possibility for Bayesian reasoning wi…
Towards semantic-based RSS merging
2009
Merging information can be of key importance in several XML-based applications. For instance, merging the RSS news from different sources and providers can be beneficial for end-users (journalists, economists, etc.) in various scenarios. In this work, we address this issue and mainly explore the relatedness relationships between RSS entities/ elements. To validate our approach, we also provide a set of experimental tests showing satisfactory results. © 2009 Springer-Verlag Berlin Heidelberg
Advanced RDB-to-RDF/OWL Mapping Facilities in RDB2OWL
2011
We present advanced features of RDB2OWL mapping specification language that allows expressing RDB-to-RDF/OWL mappings in a concise and human comprehensible way. The RDB2OWL mappings can be regarded as documentation of the database-to-ontology relation. The RDB2OWL language uses the OWL ontology structure as a backbone for mapping specification by placing the database link information into the annotations for ontology classes and properties. Its features include reuse of database table key information, user defined scalar and aggregate functions, table-based functions and multiclass conceptualization that is essential to keep mappings compact in case when large tables are mapped onto several…
ViziQuer: A Tool to Explore and Query SPARQL Endpoints
2011
The presented tool uses a novel approach to explore and query a SPARQL endpoint. The tool is simple to use as a user needs only to enter an address of a SPARQL endpoint of one's interest. The tool will extract and visualize graphically the data schema of the endpoint. The user will be able to overview the data schema and use it to construct a SPARQL query according to the data schema. The tool can be downloaded from http://viziquer.lumii.lv. There is also additional information and help on how to use it in practice.
Export of Relational Databases to RDF Databases by Model Transformations
2011
The Semantic Web is a Web of Data. To fulfill this web with data we need methods how to transfer business data from existing relational databases. In most cases, textual mapping languages are used for the specification of correspondences between relational DB schema and OWL ontology. These languages generally are rather awkward and not well-suited for the specification of mappings in cases when there is a substantial semantic gap between the source ER schema and the target OWL ontology. At the same time specification of mappings is a classical use case for graphical model transformation languages. In our previous work [10] we have proposed a new, model transformation-based method for the sp…