• Journal of the Korean Society for information Management
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• v.19 no.1
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• pp.47-69
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• 2002

The concept based retrieval model has shown a higher performance than those of the simple matching function method or the P-norm retrieval method introduced to compensate the demerits of the Boolean retrieval model. However. it takes too long to create a semantic-net knowledge base, which is essential in concept exploration. In order to solve such demerits. a method was sought out by creating a distributed knowledge base by subjects to reduce construction time without hindering the performance of retrieval.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.2 no.3
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• pp.150-170
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• 2008

In recent years, main focus of research on image retrieval techniques is on content-based image retrieval. Text-based image retrieval schemes, on the other hand, provide semantic support and efficient retrieval of matching images. In this paper, based on Formal Concept Analysis (FCA), we propose a new image indexing and retrieval technique. The proposed scheme uses keywords and textual annotations and provides semantic support with fast retrieval of images. Retrieval efficiency in this scheme is independent of the number of images in the database and depends only on the number of attributes. This scheme provides dynamic support for addition of new images in the database and can be adopted to find images with any number of matching attributes.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.22 no.2
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• pp.141-160
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• 2011

This study suggested knowledge base and search engine for the libraries that have the largescaled data. For this purpose, 3 components of knowledge bases(triple ontology, concept-based knowledge base, inverted file) were constructed and 3 search engines(search engine JENA for rule-based reasoning, Concept-based search engine, keyword-based Lucene retrieval engine) were implemented to measure their performance. As a result, concept-based retrieval engine showed the best performance, followed by ontology-based Jena retrieval engine, and then by a normal keyword search engine.

• The KIPS Transactions:PartD
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• v.9D no.1
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• pp.31-42
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• 2002

In this paper, we propose a new spatio-temporal representation scheme which can model moving objets trajectories effectively in video data and a new signature-based access method for moving objects trajectories which can support efficient retrieval on user query based on moving objects trajectories. The proposed spatio-temporal representation scheme supports content-based retrieval based on moving objects trajectories and concept-based retrieval based on concepts(semantics) which are acquired through the location information of moving objects trajectories. Also, compared with the sequential search, our signature-based access method can improve retrieval performance by reducing a large number of disk accesses because it access disk using only retrieved candidate signatures after it first scans all signatures and performs filtering before accessing the data file. Finally, we show the experimental results that proposed scheme is superior to the Li and Shan's scheme in terns of both retrieval effectiveness and efficiency.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.2
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• pp.453-460
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• 2013

This study proposes a framework that enables efficient integration and usage of enterprise data using semantic based concept net. Integration of enterprise information that has been increasing geometrically in cloud environment. The concept net is very similar in approaching way to existing ontology. However, it builds correlation between object and concept to help user's information integration retrieval more efficiently. In this study, concept nets are divided into 3 kinds and are applied to the proposed framework independently. The concept net in this study is built in ontology format based on master information concept net, keyword concept net and business process concept net. This concept net enables retrieval and usage of data based on correlation among data according to user's request. Then, through combination of master information concept and keyword concept, it provides frequency trace of keyword and category thus improving convenience and speed of retrieval.

• Asia pacific journal of information systems
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• v.16 no.4
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• pp.203-215
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• 2006

The advent of KM(knowledge management) concept have led many organizations to seek an effective way to make use of their knowledge. But the absence of right tools for systematic handling of unstructured information makes it difficult to automatically retrieve and share relevant information that exactly meet user's needs. we propose a systematic method to enable content-based information retrieval from corpus of unstructured documents. In our method, a document is represented by using several key terms which are automatically selected based on their quantitative relevancy to the document. Basically, the relevancy is calculated by using a traditional TFIDF measure that are widely accepted in the related research, but to improve effectiveness of the measure, we exploited 'concept network' that represents term-term relationships. In particular, in constructing the concept network, we have also considered relative position of terms occurring in a document. A prototype system for experiment has been implemented. The experiment result shows that our approach can have higher performance over the conventional TFIDF method.

• The KIPS Transactions:PartB
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• v.19B no.3
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• pp.183-188
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• 2012

One of the major challenge for retrieval performance is the word mismatch between user's queries and documents in information retrieval. To solve the word mismatch problem, we propose a retrieval model based on the degree of association of query concept and word translation probabilities in translation-based model. The word translation probabilities are calculated based on the set of a sentence and its succeeding sentence pair. To validate the proposed method, we experimented on TREC AP test collection. The experimental results show that the proposed model achieved significant improvement over the language model and outperformed translation-based language model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.661-663
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• 2013

The purpose of the following report is to introduce a model that makes it possible to efficiently search data by using keyword-based concept network for reliable access of information which is rapidly increasing in the mobile cloud. A keyword-based concept network is a method with the application of ontology. However, the proposed model is added by association information between keyword concepts as a method for a user's efficient information retrieval. Furthermore, the proposed concept network consists of the keyword centered concept network, expert-group-recommended field concept network, and process concept network.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.3
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• pp.303-317
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• 2002

In this paper, we design and implement E-COIRS enabling users to query with concepts and image features used for further refining the concepts. For example, E-COIRS supports the query "retrieve images containing black home appliance to north of reception set. "The query includes two types of concepts: IS-A and composite. "home appliance"is an IS-A concept, and "reception set" is a composite concept. For evaluating such a query. E-COIRS includes three important components: a visual image indexer, thesauri and a query processor. Each pair of objects in an mage captured by the visual image indexer is converted into a triple. The triple consists of the two object identifiers (oids) and their spatial relationship. All the features of an object is referenced by its old. A composite concept is detected by the triple thesaurus and IS-A concept is recolonized by the fuzzy term thesaurus. The query processor obtains an image set by matching each triple in a user with an inverted file and CS-Tree. To support efficient storage use and fast retrieval on high-dimensional feature vectors, E-COIRS uses Cell-based Signature tree(CS-Tree). E-COIRS is a more advanced content-based image retrieval system than other systems which support only concepts or image features.

• Journal of the Korea Society of Computer and Information
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• v.10 no.3 s.35
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• pp.1-10
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• 2005

This paper presents the information retrieval system which can retrieve the most appropriate answer sentence for user queries by using the concept and the attribute for the knowledge retrieval. The system analyzes the user query into the Boolean queries with the concept and the attribute and then retrieve the relevant documents in the indexing set of answer documents. Users can retrieve the relevant answer sentences from the relevant documents. For this, the answer documents indexed by the concept and the attribute are segmented by each sentence respectively. Thus, the segmented sentences are analyzed into the concept and the attribute of which the relevance degree with indexing units of documents is evaluated. Then, the system indexes the location of answer sentences. In the experiment, we evaluate the performance of our answer retrieval system against 100 user queries and show the experimental results.