Nowadays, the majority of data sources in the current web are stored in Relational Data Bases (RDB), the semantic web main idea is to solve the problem of sharing and reusing information between applications and companies in different common areas, based on data stored in RDBs. This article present a complete automatic approach that generate Ontology from a giving relational database based on a...

Since a big part of web content is stored in relational databases (RDB) there are several approaches for generating of semantic web metadata from RDB. In our previous work we designed a novel approach for RDB to RDF data transformation. This paper describes experimental comparison of our system with several means of RDF production. We benchmarked both systems for the RDB to RDF transformation a...

Laboratory fracture toughness tests of concrete using wedge-loaded round double beam specimens with a length to diameter ratio of 2:1 show two distinctly different specimen behaviors. Either the crack remains in the plane of the notch, and a valid test result can be obtained, or there is lateral cracking around mid-length which invalidates the results. Results of a controlled study show that th...

This paper presents several basic results on compiling indefinite and GCWA(Generalized Closed World Assumption) inference in IDDB(Indefinite Dedutive Databases). We do not allow function symbols, but do allow non-Horn clauses. Further, although the GCWA is used to derive negative assumptions, we do also allow negative clauses to occur explicitly. We show a fundamental relationship between indef...

During the past several years, many enterprises have created data warehouses (and data marts) in order to run applications. Data warehousing technologies used have been primarily extract-transform-load (ETL) tools, database modeling and design tools, and relational database (RDB) systems. There are three major holes in data warehousing today. These include inadequate attention to dirty data, in...

Graph data mining is highly versatile, as it applies not only to graph data but to relational data, as long as it can be represented as pairs of relationships. However, modeling RDBs as graphs using existing methods is limited in describing semantics of the relational data. In this paper, we propose a two-phased graph-modeling framework that converts any RDB to a directed graph with richer sema...

In the renewal of old process computer system of the continuous casting plant, Nippon Steel Corporation has attained cost reduction by the introduction of general-purpose PC server and OS, and middleware (NS SEMI SYSTEM) originally developed in the activity of open system solution. Also the adopting general purpose RDB to the continuous casting plant has been realized in the first time. The red...

D2RQ Mapper (http://d2rq.dbcls.jp/) is a web application to edit a mapping file of D2RQ, a middleware to bridge Relational Database (RDB) and Resource Description Framework (RDF). A D2RQ mapping file defines how to map data stored in an RDB to RDF in the turtle format, and to write it by a text editor is cumbersome. D2RQ Mapper assists you to edit it by contextualizing input forms in the mappin...

The W3C Relational Database to RDF (RDB2RDF) standards are positioned to bridge the gap between Relational Databases and the Semantic Web. The standards consist of two interrelated and complementary specifications: Direct Mapping of Relational Data to RDF and R2RML: RDB to RDF Mapping Language. In this paper we present initial results on the formal study of the R2RML mapping language by definin...

For integrating relational databases (RDBs) into semantic web applications, the W3C RDB2RDF Working Group recommended two approaches, Direct Mapping (DM) and R2RML. The DM provides a set of mapping rules according to RDB schema, while the R2RML allows users to manually define mappings according to existing target ontology. The major problem to use R2RML is the effort for creating R2RML mapping ...