Gil-Chang Kim

Query type classification for web document retrieval

The heterogeneous Web exacerbates IR problems and short user queries make them worse. The contents of web documents are not enough to find good answer documents. Link information and URL information compensates for the insufficiencies of content information. However, static combination of multiple evidences may lower the retrieval performance. We need different strategies to find target documents according to a query type. We can classify user queries as three categories, the topic relevance task, the homepage finding task, and the service finding task. In this paper, a user query classification scheme is proposed. This scheme uses the difference of distribution, mutual information, the usage rate as anchor texts, and the POS information for the classification. After we classified a user query, we apply different algorithms and information for the better results. For the topic relevance task, we emphasize the content information, on the other hand, for the homepage finding task, we emphasize the Link information and the URL information. We could get the best performance when our proposed classification method with the OKAPI scoring algorithm was used.

English-to-Korean transliteration using multiple unbounded overlapping phoneme chunks

We present in this paper the method of English-to-Korean (E-K) transliteration and back-transliteration. In Korean technical documents, many English words are transliterated into Korean words in various forms in diverse ways. As English words and Korean transliterations are usually technical terms and proper nouns, it is hard to find a transliteration and its variations in a dictionary. Therefore an automatic transliteration system is needed to find the transliterations of English words without manual intervention.To explain E-K transliteration phenomena, we use phoneme chunks that do not have a length limit. By applying phoneme chunks, we combine different length information with easy. The E-K transliteration method has three steps. In the first, we make a phoneme network that shows all possible transliterations of the given word. In the second step, we apply phoneme chunks, extracted from training data, to calculate the reliability of each possible transliteration. Then we obtain probable transliterations of the given English word.

A two-level morphological analysis of Korean

The two-level morphology model has received a great deal of attention and has been implemented for languages like Finnish, English, Japanese, Russian, French, and so on. However, this model has been claimed to be inappropriate for Korean morphological analysis, because the complex conjugation (inflection) and agglutination in word formation, and the syllable-based representation of words may lead to a huge number of two-level morphological rules. In this paper, we show that the two-level model can be successfully applied to Korean and its rule size is limited to only 52. An extension of two-level morphology is described for Korean language.

An expert system with case-based reasoning for database schema design

Abstract In this paper, we present a Design Expert System for Database Schema (DES-DS) based upon case-based reasoning. Instead of maintaining only domain cases for designing a target database schema, the proposed system relies on two case-bases that consist of a Domain Dependent Case-Base (DDCB) and a Domain Independent Case-Base (DICB). For this approach, we propose a Relational Conceptual Graph (RCG) to represent the users design specification and each case in the case-bases. The details of the system architecture, organization of the case-bases, reasoning rules, and system flow are also described.

An English-to-Korean machine translator: MATES/EK

This note introduces an English-to-Korean Machine Translation System MATES/EK, which has been developed as a research prototype and is still under upgrading in KAIST (Korea Advanced Institute of Science and Technology). MATES/EK is a transfer-based system and it has several subsystems that can be used to support other MT-developments. They are grammar developing environment systems, dictionary developing tools, a set of augmented context free grammars for English syntactic analysis, and so on.

A hybrid knowledge-based approach to information retrieval

Abstract From a couple of years ago, extensive research efforts have been devoted to the knowledge-based approach to information retrieval. These are usually based on thesauri that admit a variety of relations between control vocabularies called index terms. However, there have been few systems to offer sufficient functions enough to convey domain dependent knowledge as well as domain independent one in storing and retrieving information. This paper proposes a knowledge-based approach that facilitates not only domain independent knowledge but domain dependent one to be represented in the context of information retrieval in a simple and structured manner. It can be accomplished by separating the store of the knowledge into two boxes: domain independent knowledge Box )Ibox) and domain dependent knowledge Box (Dbox). Ibox is used as a graph-based thesaurus that permits “is-a” relation between index terms. Dbox describes domain-specific information, such as synonym relationship, some term relationships other than “is-a” relation, and generation rules for comples compound phrases. Dbox is used as the front-end to Ibox that helps to convert the arbitrary terminology given by an IR user to the index terms implied in Ibox and reflects domain dependent knowledge. The query evaluation procedure QEP retrieves the documents relevant to a query given as Boolean form, interacting with Ibox and Dbox. It, first, retrieves all related documents and takes the ones of highest rank by Radas algorithm. We show that Radas algorithm does not raise discontinuity near zero, nor counter-intuitive result in QEP, while it does in general situation.

A case-based reasoning approach to relational database schema design

We describe a design expert system for database schema based upon case-based reasoning. The proposed system relies on a hybrid case-base that consists of a domain dependent case-base (DDCB) and a domain independent case-base (DICB). With user requirements, the system searches a DDCB for a similar case. If there is one, the system uses it to design a database schema with minimum user interaction. When there is no similar case, the system uses cases in DICB to make a new schema in 3rd normal form with more user interaction. Whenever a new schema is designed, it is added to the DDCB. A DDCB is hierarchically organized to help the system reduce search space. For this approach, we propose a relational conceptual graph to represent user design specifications and each case in the case-bases.<<ETX>>

Constructing a domain dependent case-base for database schema design with case-based reasoning

This paper presents the potential for case-based reasoning in design problems, specifically as applied to relational database schema design. The proposed system relies on two case-bases that consist of a Domain Dependent Case-Base (DDCB) and a Domain Independent Case-Base (DICB). We focus on the DDCB in this paper. The organization of domain dependent cases and their features for design are identified. The strategies for retrieving the relevant cases, for building a rough solution, for repairing the rough solution, and for learning cases, currently under development, are also described.