• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1327-1335
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• 2011

XML is good at representing data with hierarchical and self-describing structure. There is no inherent semantics with XML. However, semantics of XML has come up with us as XML is used in wide and advanced applications. This paper surveyed semantics in XML data processing environment. XML semantics can be categorized into four groups according to its usage; structural semantics, relational semantics, extended semantics, and semantic web. Relational database is still a good alternative for storing and managing large volume of XML documents. We propose an extended relational semantics in order to exploit it in managing XML documents such as query processing.

• Asia pacific journal of information systems
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• v.12 no.2
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• pp.99-118
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• 2002

In this paper, we propose a visual relational database query language, VRQL, by modifying and extending the recently proposed $VOQL^*$. Like $VOQL^*$, VRQL, based on ven Diagram and graph, naturally reflects the structure of schemas in queries and has recursive formal semantics. However, VRQL has relationally complete expressiveness, while $VOQL^*$ is only a conjunctive query language. In the logical definition part of VRQL, which is the relational version of $VOQL^*$, most features of $VOQL^*$ are retained, and the semantics of queries are based on the tuple relational calculus. In the procedural definition part of VRQL, by introducing the concept of VRQL view and set operations, the expressiveness of VRQL is increased to the level equivalent to that of the relational algebra. Due to the introduction of VRQL views, existing queries or temporary queries used in the process of creating queries can be represented with views, so that complex queries may be represented more conveniently. Set operations, used with VRQL views, enable us to represent various queries, beyond the expressiveness of conjunctive query languages.

• Korean Journal of Logic
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• v.22 no.1
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• pp.25-42
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• 2019

This paper deals with Kripke-style semantics, which will be called set-theoretic Kripke-style semantics, for weakly associative substructural fuzzy logics. We first recall three weakly associative substructural fuzzy logic systems and then introduce their corresponding Kripke-style semantics. Next, we provide set-theoretic completeness results for them.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.53-63
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• 2011

Many techniques have been proposed to store and query XML data efficiently. One way achieving this goal is using relational database by transforming XML data into relational format. It is important to transform schema to preserve the content, the structure and the constraints of the semantics information of the XML document. Especially, key constraints are an important part of database theory. Therefore, the proposal technique has considered the semantics of XML as expressed by primary keys and foreign keys. And, the proposal technique can preserve not only XML data constraints but also the content and the structure and the semantics of XML data thru transformation process. Transforming information is the content and the structure of the document(the parent-child relationship), the functional dependencies, semantics of the document as captured by XML key and keyref constraints. Because of XML schema transformation ensures that preserving semantic constraints, the advantages of these transformation techniques do not need to use the stored procedure or trigger which these data ensures data integrity in the relational database. In this paper, there is not chosen the ID/IDREF key which supported in DTD, the inheritance relationship, the implicit referential integrity.

• The Transactions of the Korea Information Processing Society
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• v.3 no.1
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• pp.87-94
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• 1996

In order to design an extended relational database management system supporting multilevel security, the standard relational data model is extended and new relational integrity constrains are proposed for the model. The extended relational model and proposed multilevel integrity constraniants maintain database in consistent state and produce a basis that can eliminat eambiguity of entity and relation ship representations bypoly instantiation. The proposed up dates emantics canincreases the efficiency of up date operations by supporting multilevel entry and up dates. The semantics also provides a basis for the implementation of decomposition of extended relations.

• Journal of KIISE:Software and Applications
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• v.37 no.2
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• pp.148-154
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• 2010

In the study of the formal semantics of uncertain databases, we typically take an algebraic approach by mapping an uncertain database to possible worlds which are a set of relational databases. In this paper, we present a new semantics for uncertain databases which takes a logical approach by translating uncertain databases into logical theories. A characteristic feature of our semantics is that it uses linear logic, instead of propositional logic, as its logical foundation. Linear logic is suitable for a logical interpretation of uncertain information because unlike propositional logic, it treats logical formulae not as persistent facts but as consumable resources. As the main result, we show that our semantics is faithful to the operational account of uncertain databases in the algebraic approach.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.240-245
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• 1998

Fuzzy information retrieval which uses the concept of fuzzy relation is able to retrieve documents in the way based on not morphology but semantics, dissimilar to traditional information retrieval theories. Fuzzy information retrieval logically consists of three sets : the set of documents, the set of terms and the set of queries. It maintains a fuzzy relational matrix which describes the relationship between documents and terms and creates a thesaurus with fuzzy relational product. It also provides the user with documents which are relevant to his query. However, there are some problems on building a thesaurus with fuzzy relational product such that it has big time complexity and it uses fuzzy values to be processed with flating-point. Actually, fuzzy values have to be expressed and processed with floating-point. However, floating-point operations have complex logics and make the system be slow. If it is possible to exchange fuzzy values with binary values, we could expect sp eding up building the thesaurus. In addition, binary value expressions require just a bit of memory space, but floating -point expression needs couple of bytes. In this study, we suggest a new method of building a thesaurus, which accelerates the operation of the system by pre-applying an ${\alpha}$-cut. The experiments show the improvement of performance and reliability of the system.

• Journal of Internet Computing and Services
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• v.8 no.2
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• pp.95-103
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• 2007

Many techniques have been proposed for mapping from XML to relations, but most techniques did not negotiate the semantics of XML data. The semantics is important to validate storage, query optimization, modification anomaly in process of schema design. Specially, functional dependencies are an important part of database theory, also it is basis of normalization for relational table in BCNF. This paper propose a new technique that reflect functional dependencies to store relation mapped from XML based on XML Schema. The technique can reduce storage redundancy and can keep up content and structure with constraint described by functional dependencies.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.183-186
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• 1996

The relational database management systems sometimes require extremely long and complicated queries for a certain retreval. In this case, recursive retirevals are more efficient approach than the usual queries. Many researchers have tried to incorporate semantics in the traditional relational models using artificial intelligence techniques. This new concept becomes a deductive database and sometimes it is also called as a logic programming. However, the designer of a deductive database did not overcome the short of relational database. In this paper, we propose a new way of designing queries for the deductive database. We also provide relations for recursive retrieval in the deductive database. These approaches are applied for the material requirement planning.

• The Journal of Information Systems
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• v.18 no.3
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• pp.327-349
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• 2009

Traditional keyword-based searching methods suffer from low accuracy and high complexity due to the rapid growth in the amount of information. Accordingly, many researchers attempt to implement a so-called semantic search which is based on the semantics of the user's query. Semantic information can be described using a semantic modeling language, such as Topic Map. In this paper, we propose a new method to map a topic map to a traditional Relational Database (RDB) without any information loss. Although there have been a few attempts to map topic maps to RDB, they have paid scant attention to handling multi-role topics. In this paper, we propose a new storage structure to map multi-role topics to traditional RDB. The proposed structure consists of a mapping table, role tables, and content tables. Additionally, we devise a query translator to convert a user's query to one appropriate to the proposed structure.