• Title/Summary/Keyword: Tree-structured Query

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A Study on Processing XML Documents (XML 문서 처리에 관한 연구)

  • Kim, Tae Gwon
    • Journal of KIISE
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    • v.43 no.4
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    • pp.489-496
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    • 2016
  • XML can effectively express structured or semi-structured data as well as relational databases. XQuery is a query language for retrieving information for such an XML document. In this paper, an XQuery composer is designed and implemented, with an API provided for XQuery processors, and a proper processor is registered. This composer shows query results immediately processed by the processor. As this composer contains a parser for XQuery, it can compose XQuery effectively using a diverse dialog box designed for XQuery grammar. A dialog box is affiliated with a clause region, which is a region that algebra operates from the parsing tree. It can compose path expressions for an XML document easily as it shows an element tree from DTD graphically. Path expressions are composed automatically by marking elements in the structural hierarchy and by specifying the predicate of an element partially.

Dynamic recomposition of document category using user intention tree (사용자 의도 트리를 사용한 동적 카테고리 재구성)

  • Kim, Hyo-Lae;Jang, Young-Cheol;Lee, Chang-Hoon
    • The KIPS Transactions:PartB
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    • v.8B no.6
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    • pp.657-668
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    • 2001
  • It is difficult that web documents are classified with exact user intention because existing document classification systems are based on word frequency number using single keyword. To improve this defect, first, we use keyword, a query, domain knowledge. Like explanation based learning, first, query is analyzed with knowledge based information and then structured user intention information is extracted. We use this intention tree in the course of existing word frequency number based document classification as user information and constraints. Thus, we can classify web documents with more exact user intention. In classifying document, structured user intention information is helpful to keep more documents and information which can be lost in the system using single keyword information. Our hybrid approach integrating user intention information with existing statistics and probability method is more efficient to decide direction and range of document category than existing word frequency approach.

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Adaptive Path Index for Efficient U Query Processing (효율적인 XML 질의 처리를 위한 적응형 경로 인덱스)

  • 민준기;심규석;정진완
    • Journal of KIISE:Databases
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    • v.31 no.1
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    • pp.61-71
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    • 2004
  • XML can describe a wide range of data, from regular to irregular and from flat to deeply nested. Thus, XML is rapidly emerging as the do facto standard for the Web document format since XML supports an efficient data exchange and integration. Also, to retrieve the data represented by XML, several XML query languages are proposed. XML query languages such as XPath and XQuery use path expressions to traverse irregularly structured data which comprise B% elements. To evaluate path expressions, various path indexes are proposed. However, traditional path indexes are constructed by utilizing only the XML data structure. Therefore, in this paper, we propose an adaptive path index which utilizes the XML data structure as well as query workloads. To improve the query performance, the adaptive path index proposed by this paper manages the frequently used paths and the structural summary of the XML data using a hash tree and a graph structure. Experimental results show that the adaptive path index improves the query performance typically 2 to 69 times compared with the existing indexes.

Design of Algorithm for Efficient Retrieve Pure Structure-Based Query Processing and Retrieve in Structured Document (구조적 문서의 효율적인 구조 질의 처리 및 검색을 위한 알고리즘의 설계)

  • 김현주
    • Journal of the Korea Computer Industry Society
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    • v.2 no.8
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    • pp.1089-1098
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    • 2001
  • Structure information contained in a structured document supports various access paths to document. In order to use structure information contained in a structured document, it is required to construct an index structural on document structures. Content indexing and structure indexing per document require high memory overhead. Therefore, processing of pure structure queries based on document structure like relationship between elements or element orders, low memory overhead for indexing are required. This paper suggests the GDIT(Global Document Instance Tree) data structure and indexing scheme about structure of document which supports low memory overhead for indexing and powerful types of user queries. The structure indexing scheme only index the lowest level element of document and does not effect number of document having retrieval element. Based on the index structure, we propose an query processing algorithm about pure structure, proof the indexing schemes keeps up indexing efficient in terms of space. The proposed index structure bases GDR concept and uses index technique based on GDIT.

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Linear Path Query Processing using Backward Label Path on XML Documents (역방향 레이블 경로를 이용한 XML 문서의 선형 경로 질의 처리)

  • Park, Chung-Hee;Koo, Heung-Seo;Lee, Sang-Joon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.17 no.6
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    • pp.766-772
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    • 2007
  • As XML is widely used, many researches on the XML storage and query processing have been done. But, previous works on path query processing have mainly focused on the storage and retrieval methods for a large XML document or XML documents had a same DTD. Those researches did not efficiently process partial match queries on the differently-structured document set. To resolve the problem, we suggested a new index structure using relational table. The method constructs the $B^+$-tree index using backward label paths instead of forward label paths used in previous researches for storing path information and allows for finding the label paths that match the partial match queries efficiently using it when process the queries.

An Indexing Scheme for Efficient Retrieval and Update of Structured Documents Based on GDIT (GDIT를 기반으로 한 구조적 문서의 효율적 검색과 갱신을 위한 인덱스 설계)

  • Kim, Young-Ja;Bae, Jong-Min
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.2
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    • pp.411-425
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    • 2000
  • Information retrieval systems for structured documents which are written in SGML or XML support partial retrieval of document. In order to efficiently process queries based on document structures, low memory overhead for indexing, quick response time for queries, supports to powerful types of user queries, and minimal updates of index structure for document updates are required. This paper suggests the Global Document Instance Tree(GDIT) and proposes an effective indexing scheme and query processing algorithms based on the GDIT. The indexing scheme keeps up indexing and retrieval effciency and also guarantees minimal updates of the index structure when document structures are updated.

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A Study on Flexible Attribude Tree and Patial Result Matrix for Content-baseed Retrieval and Browsing of Video Date. (비디오 데이터의 내용 기반 검색과 브라우징을 위한 유동 속성 트리 및 부분 결과 행렬의 이용 방법 연구)

  • 성인용;이원석
    • Journal of Korea Multimedia Society
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    • v.3 no.1
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    • pp.1-13
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    • 2000
  • While various types of information can be mixed in a continuous video stream without any cleat boundary, the meaning of a video scene can be interpreted by multiple levels of abstraction, and its description can be varied among different users. Therefore, for the content-based retrieval in video data it is important for a user to be able to describe a scene flexibly while the description given by different users should be maintained consistently This paper proposes an effective way to represent the different types of video information in conventional database models such as the relational and object-oriented models. Flexibly defined attributes and their values are organized as tree-structured dictionaries while the description of video data is stored in a fixed database schema. We also introduce several browsing methods to assist a user. The dictionary browser simplifies the annotation process as well as the querying process of a user while the result browser can help a user analyze the results of a query in terms of various combinations of Query conditions.

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Design of Efficient Storage Structure and Indexing Mechanism for XML Documents (XML을 위한 효율적인 저장구조 및 인덱싱 기법설계)

  • 신판섭
    • Journal of the Korea Computer Industry Society
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    • v.5 no.1
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    • pp.87-100
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    • 2004
  • XML has recently considered as a new standard for data presentation and exchange on the web, many researches are on going to develop applications and index mechanism to store and retrieve XML documents efficiently. In this paper, design a Main-Memory based XML storage system for efficient management of XML document. And propose structured retrieval of XML document tree which reduce the traverse of XML document tree using element type information included user queries. Proposed indexing mechanism has flexibilities for dynamic data update. Finally, for query processing of XML document include Link information, design a index structure of table type link information on observing XLink standards.

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Efficient Peer-to-Peer Lookup in Multi-hop Wireless Networks

  • Shin, Min-Ho;Arbaugh, William A.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.3 no.1
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    • pp.5-25
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    • 2009
  • In recent years the popularity of multi-hop wireless networks has been growing. Its flexible topology and abundant routing path enables many types of applications. However, the lack of a centralized controller often makes it difficult to design a reliable service in multi-hop wireless networks. While packet routing has been the center of attention for decades, recent research focuses on data discovery such as file sharing in multi-hop wireless networks. Although there are many peer-to-peer lookup (P2P-lookup) schemes for wired networks, they have inherent limitations for multi-hop wireless networks. First, a wired P2P-lookup builds a search structure on the overlay network and disregards the underlying topology. Second, the performance guarantee often relies on specific topology models such as random graphs, which do not apply to multi-hop wireless networks. Past studies on wireless P2P-lookup either combined existing solutions with known routing algorithms or proposed tree-based routing, which is prone to traffic congestion. In this paper, we present two wireless P2P-lookup schemes that strictly build a topology-dependent structure. We first propose the Ring Interval Graph Search (RIGS) that constructs a DHT only through direct connections between the nodes. We then propose the ValleyWalk, a loosely-structured scheme that requires simple local hints for query routing. Packet-level simulations showed that RIGS can find the target with near-shortest search length and ValleyWalk can find the target with near-shortest search length when there is at least 5% object replication. We also provide an analytic bound on the search length of ValleyWalk.

The Algorithm For Spatial XQuery2SQL Converter (Spatial XQuery2SQL Converter를 위한 알고리즘)

  • Choi, Young Nn;Seo, Hyun-Ho
    • Proceedings of the Korea Contents Association Conference
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    • 2004.11a
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    • pp.442-447
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    • 2004
  • XML is normalized text form that is designed to transmit structured document in web as that propose in W3C (World Wide Web Consortium) in 1996. Function that this can overcome HTML's limit that use in existing in Internet and user define new tag to HTML by way to solve SGML's complexity added. There is many efforts to use storing this XML document in RDBMS but to relation style DB because XML document is tree structure structurally data SQL and perfect disaster caused by things that is language to ask a question accomplish XQuery that so it is W3C's XML standard query appear. After store XML informations including space information to RDBMS in this paper, Spatial XQuery through converter that is Sqatial XQuery2SQL through Spatial operator, Spatial function SQL of by Sqatial XQuery2SQL conversion algorithm that draw information in RDBMS after change embody wish to.

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