• Journal of the Korean Society for information Management
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• v.21 no.2
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• pp.189-210
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• 2004

The purpose of this study is to evaluate the performance of XML retrieval based on ORDBMSs(Object-Relational Database Management Systems) approach. This paper describes indexing and retrieval methods for XML documents and the methodologies of experiments at INEX(Initiative for the Evaluation of XML retrieval). Like any other traditional information retrieval experiment, the test collection was consists of documents, topics/queries, task, relevance assessments and evaluation. EXIMA$^{TM}$ Supply, a kind of native XML DB based on ORDBMS technologies, is used for this experiment. Although this approach has many benefits, for example, no delay in storing and searching XML documents. but it showed relatively disappointed retrieval performance at INEX 2002. This result may caused since the given topics had to be decomposed and modified to be processed by the XPath processor, and during this modification the original meaning of topics can be changed inevitably and some important information nay pass over.r.

• Journal of KIISE:Databases
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• v.31 no.5
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• pp.553-566
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• 2004

Some of the current main research areas involving techniques related to XML consist of storing XML documents, optimizing the query, and indexing. As such we may focus on the set of documents that are composed of various structures, but that are not shared with common structure such as the same DTD or XML Schema. In the case, it is essential to analyze structural similarities and differences among many documents. For example, when the documents from the Web or EDMS (Electronic Document Management System) are required to be merged or classified, it is very important to find the common structure for the process of handling documents. In this paper, we transformed sequential pattern mining algorithms(1) to extract maximal similar paths between two XML documents. Experiments with XML documents show that our transformed sequential pattern mining algorithms can exactly find common structures and maximal similar paths between them. For analyzing experimental results, similarity metrics based on maximal similar paths can exactly classify the types of XML documents.

• The KIPS Transactions:PartD
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• v.12D no.3 s.99
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• pp.439-446
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• 2005

XML is the standard that can manage systematically WWW documents and increase retrieval efficiency. Because XML documents have the information of contents and that of structure in single document, users can get more suitable retrieval result by retrieving the information of content as well as that of logical structure. In this paper, we will propose a method to calculate the weights of XML tags so that the information of XML tag is used to index decision. A proposed method creates term vector and weight vector for XML tags, and calculates weight of tag by reflecting user's retrieval behavior (user's query). And it decides the weights of index terms of XML document by reflecting the weights of tags. And we will perform an evaluation of proposed method by comparison with existing researches using weights of paragraphs.

• The Journal of Society for e-Business Studies
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• v.17 no.3
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• pp.61-72
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• 2012

Since XML allows users to define any tags, XML documents with various structures have been created. Accordingly, many studies on clustering and searching the XML documents based on the similarity of paths have been done in order to manage the documents efficiently. To retrieve XML documents having similar structures, the three-dimensional bitmap indexing technique uses a path as a unit when it creates an index. If a path structure is changed, the technique recognizes it as a new path. Thus, another technique to measure the similarity of paths was proposed. To compute the similarity between two paths, the technique compares every node of the paths. It causes unnecessary comparison of the nodes, which do not exist in common between the two paths. In this paper, we propose a new technique that minimizes the comparison using signatures and show the performance evaluation results of the technique. The comparison speed of proposed technique was 20 percent faster than the existing technique.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.1
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• pp.109-116
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• 2021

Since RDF (Resource Description Framework) triples are modeled as graph, we cannot directly adopt existing solutions in relational databases and XML technology. In order to store, index, and query Linked Data more efficiently, we propose a convergence indexing method combined R*-tree and K-dimensional trees. This method uses a hybrid storage system based on HDD (Hard Disk Drive) and SSD (Solid State Drive) devices, and a separated filter and refinement index structure to filter unnecessary data and further refine the immediate result. We perform performance comparisons based on three standard join retrieval algorithms. The experimental results demonstrate that our method has achieved remarkable performance compared to other existing methods such as Quad and Darq.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.5
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• pp.416-426
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• 2005

A B2Bi system needs a message storage subsystem that efficiently logs and searches XML messages which have been sent from orreceived by it. XML database systems and XML enabled relational databases systems are not adequate as a message storage system because of their expensiveness and excessiveness in functionality. Storage schemes that split XML messages into database records are also unacceptable because of either low performance or implementation hardness. In this paper, we propose a storage scheme that can be applied to implement a message storage system based on a relational database system. In this scheme, messages are examined only through the index fields that have been registered for each message types. Therefore, the proposed storage scheme cannot support such a powerful search facility like XQL, but it provides high performance message legging and restricted search facility. There are three alternative database schemas to store the index fields. This paper compares the advantages and disadvantages of the three schemas through experimental tests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.1
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• pp.39-45
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• 2006

본 연구는 웹기반 3차원 패션몰 구축에서 의류에 대한 정보를 보다 세부적이고 전문적인 정보로 제공하기 위하여 의상 정보를 2차원 재단 패턴의 피스(piece) 정보로 구분한다. 구분된 피스는 의상에 따라 상하종속관계에 해당하는 피스정보별 상세정보를 가중치에 따라 검색하여 SVG(Scalable Vector Graphics) 파일 형태로 제공하도록 설계하였다. 이러한 의상 상세정보를 통해 디자이너가 의상구조의 다양한 조합으로 새로운 제품 디자인이 용이해지고 유사한 형태의 의상 표현이 가능해진다. 이를 통해 패션몰 상품에 대한 전문가적인 의상 분석도 가능해진다. 또한 SVG 형식의 파일을 이용하기 때문에 부하가 많은 쇼핑몰의 정보 표현에도 용이하다. 이를 위해 구축된 정보는 XML로 표준화 할 수 있도록 DTD(Document Type Definition)를 정의하여 검색 시스템을 설계하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05c
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• pp.1519-1522
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• 2003

기존의 웹 문서나 컨텐츠들의 표현적 한계를 극복하기 위한 방안으로 메타 데이터에 관한 다양한 연구가 수행되어졌고 그 결과의 산물중에 가장 대표적인 것으로 XML을 들 수 있다. XML은 문서의 내용뿐 아니라 구조까지도 기술할 수 있는 장점을 통해 향후 정보 교환에 핵심적인 역할을 할 것으로 기대되어지고 있으며 이에 따라 XML 문서를 효율적으로 저장하고 검색하기 위한 다양한 연구가 진행되고 있다. BitCube는 Bit-wise 연산이 가능한 3차원 비트맵 인덱싱을 사용하여 XML 문서들의 구조적 유사성에 따라 클러스터링하고 사용자의 질의에 대한 처리를 수행하는 인덱싱 기법으로 그것의 빠른 성능을 입증하였다. 그러나 BitCube의 클러스터링은 XML 문서의 경로에 중점을 둔 것이므로 클러스터와 경로가 담고 있는 실제 단어들간에는 연관성이 없으므로 3차원 비트맵 인덱스는 하나의 평면을 제외한 모든 평면이 굉장히 높은 공간 사용량을 갖는 회소행렬이 된다. 본 논문에서는 늘어나는 방대한 문서의 양으로 인한 시스템의 성능 저하를 막고 안정적인 성능을 유지할 수 있도록 기존 연산의 성능을 저하시키지 않으면서 공간을 최소화 할 수 있는 연결 리스트틀 설계하고 3차원 비트맵 인덱스를 연결 리스트로 재구성하는 방법을 제시한다.

• Journal of Creative Information Culture
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• v.7 no.3
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• pp.157-165
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• 2021

As the use of various application services utilizing Web and IoT and the need for large amounts of data management expand accordingly, the importance of efficient data expression and exchange scheme and data query processing is increasing. JSON, characterized by its simplicity, is being used in various fields as a format for data exchange and data storage instead of XML, which is a standard data expression and exchange language on the Web. This means that it is important to develop indexing and query processing techniques to effectively access and search large amounts of data expressed in JSON. Therefore, in this paper, we modeled JSON data with a hierarchical structure in a tree form, and proposed indexing and query processing using the path concept. In particular, we designed an index structure using a suffix array widely used in text search and introduced simple and complex path-based JSON data query processing methods.

• Journal of KIISE:Databases
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• v.36 no.1
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• pp.50-62
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• 2009

In wireless and mobile environments, data broadcasting is recognized as an effective way for data dissemination due to its benefits to bandwidth efficiency, energy-efficiency, and scalability. In this paper, we address the problem of delayed query processing raised by tree-based index structures in wireless broadcast environments, which increases the access time of the mobile clients. We propose a novel distributed index structure and a clustering strategy for streaming XML data which enable energy and latency-efficient broadcast of XML data. We first define the DIX node structure to implement a fully distributed index structure which contains tag name, attributes, and text content of an element as well as its corresponding indices. By exploiting the index information in the DIX node stream, a mobile client can access the wireless stream in a shorter latency. We also suggest a method of clustering DIX nodes in the stream, which can further enhance the performance of query processing over the stream in the mobile clients. Through extensive performance experiments, we demonstrate that our approach is effective for wireless broadcasting of XML data and outperforms the previous methods.