Suphamit Chittayasothorn

A Transformation from RDF Documents and Schemas to Relational Databases

At present, resource description framework (RDF) documents and schemas (RDFS) are used to describe information in the semantic Web. Many research works regard the RDF/RDFS documents as databases and proposed data manipulations for them. This research paper takes a different approach. In order to easily manipulate the database, RDF/RDFS documents are transformed into relational database format so that relational languages, data management and business intelligence facilities which are readily available can be exploited. A conceptual meta schema that describes RDF/RDFS documents and the corresponding meta table are presented together with illustrated examples.

XML schema re-engineering using a conceptual schema approach

At present, the Extensible Markup Language (XML) is popular for both data presentation and data transfer activities. XML Documents follow XML Schemas. It is possible to use them as database schemas and databases. An XML Schema can be hierarchical or flat. The hierarchical one is normally used for data presentation and the flat one is for data transfer. This research project emphasizes on the data transfer application of XML. The objective of the project is to develop a technique to reengineer poorly designed XML Schemas into the normalized ones. A software tool is developed. The tool accepts well-formatted XML Schemas and well-formatted and validated XML documents as data sources. They are reengineered into the optimal normal form schemas which guarantee not to have redundancies. The Nijssens Information Analysis Methodology (NIAM) is used as the conceptual schema model of XML databases.

A temporal object relational SQL language with attribute timestamping in a temporal transparency environment

In this paper, a temporal object relational SQL language is proposed. It is intended to facilitate the non-procedural data definitions, queries, and modifications of temporal databases with attribute timestamping in a temporal transparency environment. With attribute timestamping, temporal data of any type is naturally handled. With temporal logic, users can issue temporal queries in an intuitively expressive manner. The language provides valid time support for upward compatibility, temporal upward compatibility, sequenced and non-sequenced variants to serve both non-temporal and temporal users. Using object relational technology, the implementation is made for embedded and interactive SQL modes. All existing interfaces of an ORDBMS are inherited with temporal transparency.

A frame-based object relational expert database system

An expert database system is an expert system which is developed on databases using DBMS technology to manage facts and rules. Frame-based expert systems are widely used as the knowledge representation for such expert systems with large knowledge bases. Many systems have the ability to connect to external databases. Facts stored in databases can be loaded into expert systems knowledge base and inference is performed by the inference engine of the expert system. In many cases, such external facts are required several times for each inference. Thus, a lot of communication traffic takes place. This research work present the design and implementation of a frame-based object-relational database system which has a tight coupling between the expert system and the external knowledge base. The external knowledge base also use frame as its knowledge representation. More over, it has its own inference engine so that inference can be perform on the knowledge base side and the results, not only simple facts, are sent back to the expert system for further inference. A medical consultation system is used as an illustrated example an Oracle lOg object relational DBMS is used as the database platform.

An object and XML database schemas design tool

Nowadays relational database schemas are designed by using well-known database design techniques such as the entity relationship model and the normalization process. The result schemas can be guaranteed to have minimum redundancies if the fifth normal form (5NF) is achieved. However, in more recent database schema design such as the design of object database schema, the concern about minimum redundancies does not seem to be an important issue. Functional dependencies may still appear in an object class of the class diagram thus introduce update anomalies. This article first presents the use of NIAM, a well-established conceptual schema model, as a conceptual model for the design of object databases. A transformation from a NIAM to an OODB schema with minimum redundancy is presented. The conceptual schema can also be transformed into Extensible Markup Language (XML) which is originally a language for document management. However, it now gains popularity in database representation. It is particularly useful as a data format when an application must communicate with another application. This article also presents the NIAM conceptual schema model as a conceptual design tool for XML schema. A software tool that allows users to create NIAM schemas and generate object and XML schemas is developed.

A Temporal Meta Database System for 3D Objects

Nowadays, semantic information accompanying 3D graphical data, which is called metadata, has been realized to be essential for several purposes such that available 3D graphical data can be indexed and retrieved by means of its metadata and then other applications can make use of the 3D graphical data efficiently. Even though a number of works have focused on this topic so far, no temporal aspect of 3D graphical data has been taken into account. Especially no complete automatic metadata extraction process has been proposed. A manual process is possible with a small amount of 3D graphical data while impossible with a larger amount. Therefore, the manual process gets heavy and the cost in time and effort is so much required. In such a context, we introduce for 3D graphical data a temporal meta database system where an automatic metadata extraction method takes into consideration the temporal aspect of 3D graphical data. 3D graphical data is arranged in a scene formatted in the standard language VRML. Semantic information of the scene, i.e. metadata, will be automatically achieved. The structure of scene metadata is handled by using the temporal NIAM object oriented conceptual schema model at the abstraction level so that the semantic scene information can get more understandable to users, graphics designers, and application programmers as well. As a result, scene metadata is able to be easily stored and queried by means of some standardized database language such as SQL or OQL. With the aid of the extracted scene metadata, the respective 3D scenes are now exactly and conveniently accessed by other applications such as a virtual guide in transportation, architecture, tourism, etc.

A Temporal Relational and Object Relational Database Design Technique

The NIAM (Nijssen’s Information Analysis Methodology) conceptual schema model was originated in the 1970s and later became more popular under a new name ORM (Object Role Model). It is a fact-based conceptual schema model that can be represented by graphical diagrams or described by a formal natural language. Since all relationship types are elementary, they cannot be further decomposed. This property enables the ORM conceptual schema diagram to be transformed into 5NF relational database schemas. This paper presents temporal database application development using TORM, a temporal extension to the ORM conceptual schema model. The notions of valid time and life span are introduced to the entity type and fact type concepts. An implementation of a TORM conceptual schema on relational and object relational database schemas are also presented.

A Conceptual Schema Based XML Schema with Integrity Constraints Checking

The more popular XML for exchanging and representing information on Web, the more important flat XML (XML) and intelligent editors become. For data exchanging, an XML data with an XML Schema and integrity constraints are preferred. We employ an object-role modeling (ORM) for enriching the XML Schema constraints and providing better validation the XML Data. An XML conceptual schema is presented using the ORM conceptual model. Editor Meta Tables are generated from the conceptual schema diagram and are populated. A User XML Schema base on the information in the editor meta tables is generated. However, W3C XML Schema language does not support all of the ORM constraints. Therefore, we propose an Editor XML Schema and an Editor XML Data to cover unsupported the ORM constraints. We propose the algorithms for defining constraint in the User XML Schema and extending validity constraint checking. Finally, XQuery is used for extending validity checking.

Toward fuzzy temporal databases with temporal fuzzy linguistic terms

Fuzzy databases have been proposed by many researchers for handling fuzziness in databases. Fuzzy linguistic terms are used instead of crisp values. They find applications in areas where exact or crisp values cannot always be obtained. In another database research area, temporal databases find applications where facts which are true in the past, as well as facts that will be true in the future are recorded together with current facts. There are also cases where fuzzy databases are also temporal. In most other works, fuzzy facts are temporal or the time itself is fuzzy. This paper presents the concept of a different fuzzy database where fuzzy linguistic terms are temporal. Sample queries and meta tables for temporal similarity degrees and temporal possibility distribution are also presented.

Deriving Conceptual Schema from XML Databases

In this paper, two concepts from different research areas are addressed together, namely functional dependency (FD) and multidimensional association rule (MAR). FD is a class of integrity constraints that have gained fundamental importance in relational database design. MAR is a class of patterns which has been studied rigorously in data mining. We employ MAR to mine the interesting rules from XML Databases. The mined interesting rules are considered as candidate FDs whose all confidence itemsets are 100%. To prune the weak rules, we pay attention to support and correlation itemsets. The final strong rules are used to generate an Object-Role Model conceptual schema diagram.