• Title/Summary/Keyword: databases

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Selectivity Estimation for Timestamp Queries (시점 질의를 위한 선택율 추정)

  • Shin, Byoung-Cheol;Lee, Jong-Yun
    • Journal of KIISE:Databases
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    • v.33 no.2
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    • pp.214-223
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    • 2006
  • Recently there is a need to store and process enormous spatial data in spatio-temporal databases. For effective query processing in spatio-temporal databases, selectivity estimation in query optimization techniques, which approximate query results when the precise answer is not necessary or early feedback is helpful, has been studied. There have been selectivity estimation techniques such as sampling-based techniques, histogram-based techniques, and wavelet-based techniques. However, existing techniques in spatio-temporal databases focused on selectivity estimation for future extent of moving objects. In this paper, we construct a new histogram, named T-Minskew, for query optimization of past spatio-temporal data. We also propose an effective selectivity estimation method using T-Minskew histogram and effective histogram maintenance technique to prevent frequent histogram reconstruction using threshold.

A Systemic Review of Randomized Controlled Trials on Interventions of Korean Medicine for Secondary Amenorrhea (속발성 무월경의 한의학적 치료에 대한 무작위 대조 임상시험의 체계적 문헌 고찰)

  • Eon-Ji Rho;Dong-Chul Kim
    • The Journal of Korean Obstetrics and Gynecology
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    • v.36 no.3
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    • pp.95-113
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    • 2023
  • Objectives: The purpose of this study is to review the recent clinical study trends on Korean Medicine treatment for Secondary Amenorrhea by analyzing randomized controlled trials. Methods: We searched relevant studies published from electric databases including 4 domestic databases and 3 foreign databases. Data retrieval was conducted on May 30, 2023. and the papers published from January 1, 2018 to May 30, 2023 were included. The risk of bias was assessed by using Cochrane's risk of bias tool. Results: 119 studies and 193 studies were searched in each domestic databases and foreign databases, and 9 studies were finally selected. The control group was all treated with only western medicine. Among the treatment group, 2 studies were treated with only oral herbal medicine, 1 study was treated with herbal medicine and acupuncture, 5 studies were treated with combined treatment of herbal medicine and western medicine, 1 study was treated with combined treatment of herbal medicine, acupuncture and western medicine. In all 9 studies, the total effective rate and cure rate were higher in the treatment group than those of the control group (p<0.05). Conclusions: Korean medicine alone or combined with western medicine is more effective for treating Secondary Amenorrhea compared to using western medicine alone.

Methodology for Extended Schema Representation in Database Integration

  • 김철호
    • Journal of the military operations research society of Korea
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    • v.23 no.2
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    • pp.85-102
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    • 1997
  • There have been several research efforts to support interoperability among multiple databases. In integrating multiple databases, we must resolve schema conflicts due to the heterogeneity in databases. To resolve these conflicts, not only meta-data for database schemas but also general knowledge expressing the real world meanings associated with the database schemas are required. This paper presents a uniform representation method for relational schema and general knowledge base that is composed, among other things, of concept hierarchy and thematic roles in relationship, using the knowledge representation language Lk. This representation method has a flexible descriptive power which facilitates concepts to be expressed at different levels of granularity and can describe knowledge expressed in Lk are used for input of the next step, such as conflict resolution and query processing of multiple database.

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Protein Interaction Databases and Its Application (단백질 상호작용 데이터베이스 현황 및 활용 방안)

  • Kim, Min Kyung;Park, Hyun Seok
    • IMMUNE NETWORK
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    • v.2 no.3
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    • pp.125-132
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    • 2002
  • In the past, bioinformatics was often regarded as a difficult and rather remote field, practiced only by computer scientists and not a practical tool available to biologists. However, the various on-going genome projects have had a serious impact on biological sciences in various ways and now there is little doubt that bioinformatics is an essential part of the research environment, with a wealth of biological information to analyze and predict. Fully sequenced genomes made us to have additional insights into the functional properties of the encoded proteins and made it possible to develop new tools and schemes for functional biology on a proteomic scale. Among those are the yeast two-hybrid system, mass spectrometry and microarray: the technology of choice to detect protein-protein interactions. These functional insights emerge as networks of interacting proteins, also known as "pathway informatics" or "interactomics". Without exception it is no longer possible to make advances in the signaling/regulatory pathway studies without integrating information technologies with experimental technologies. In this paper, we will introduce the databases of protein interaction worldwide and discuss several challenging issues regarding the actual implementation of databases.

Development of Active Data Mining Component for Web Database Applications (웹 데이터베이스 응용을 위한 액티브데이터마이닝 컴포넌트 개발)

  • Choi, Yong-Goo
    • Journal of Information Technology Applications and Management
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    • v.15 no.2
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    • pp.1-14
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    • 2008
  • The distinguished prosperity of information technologies from great progress of e-business during the last decade has unavoidably made software development for active data mining to discovery hidden predictive information regarding business trends and behavior from vary large databases. Therefore this paper develops an active mining object(ADMO) component, which provides real-time predictive information from web databases. The ADMO component is to extended ADO(ActiveX Data Object) component to active data mining component based on COM(Component Object Model) for application program interface(API). ADMO component development made use of window script component(WSC) based on XML(eXtensible Markup Language). For the purpose of investigating the application environments and the practical schemes of the ADMO component, experiments for diverse practical applications were performed in this paper. As a result, ADMO component confirmed that it could effectively extract the analytic information of classification and aggregation from vary large databases for Web services.

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Self Maintainable Data Warehouse Views for Multiple Data Sources (다중 데이터 원천을 가지는 데이터웨어하우스 뷰의 자율갱신)

  • Lee, Woo-Key
    • Asia pacific journal of information systems
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    • v.14 no.3
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    • pp.169-187
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    • 2004
  • Self-maintainability of data warehouse(DW) views is an ability to maintain the DW views without requiring an access to (i) any underlying databases or (ii) any information beyond the DW views and the delta of the databases. With our proposed method, DW views can be updated by using only the old views and the differential files such as different files, referential integrity differential files, linked differential files, and backward-linked differential files that keep the truly relevant tuples in the delta. This method avoids accessing the underlying databases in that the method achieves self-maintainability even in preparing auxiliary information. We showed that out method can be applicable to the DW views that contain joins over relations in a star schema, a snowflake schema, or a galaxy schema.

Emerging Data Management Tools and Their Implications for Decision Support

  • Eorm, Sean B.;Novikova, Elena;Yoo, Sangjin
    • Journal of Korea Society of Industrial Information Systems
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    • v.2 no.2
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    • pp.189-207
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    • 1997
  • Recently, we have witnessed a host of emerging tools in the management support systems (MSS) area including the data warehouse/multidimensinal databases (MDDB), data mining, on-line analytical processing (OLAP), intelligent agents, World Wide Web(WWW) technologies, the Internet, and corporate intranets. These tools are reshaping MSS developments in organizations. This article reviews a set of emerging data management technologies in the knowledge discovery in databases(KDD) process and analyzes their implications for decision support. Furthermore, today's MSS are equipped with a plethora of AI techniques (artifical neural networks, and genetic algorithms, etc) fuzzy sets, modeling by example , geographical information system(GIS), logic modeling, and visual interactive modeling (VIM) , All these developments suggest that we are shifting the corporate decision making paradigm form information-driven decision making in the1980s to knowledge-driven decision making in the 1990s.

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An Information System Architecture for Extracting Key Performance Indicators from PDM Databases (PDM 데이터베이스로부터 핵심성과지표를 추출하기 위한 정보 시스템 아키텍쳐)

  • Do, Namchul
    • Journal of Korean Institute of Industrial Engineers
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    • v.39 no.1
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    • pp.1-9
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    • 2013
  • The current manufacturers have generated tremendous amount of digitized product data to efficiently share and exchange it with other stakeholders or various software systems for product development. The digitized product data is a valuable asset for manufacturers, and has a potential to support high level strategic decision makings needed at many stages in product development. However, the lack of studies on extraction of key performance indicators(KPIs) from product data management(PDM) databases has prohibited manufacturers to use the product data to support the decision makings. Therefore this paper examines a possibility of an architecture that supports KPIs for evaluation of product development performances, by applying multidimensional product data model and on-line analytic processing(OLAP) to operational databases of product data management. To validate the architecture, the paper provides a prototype product data management system and OLAP applications that implement the multidimensional product data model and analytic processing.

An experiment to enhance subject access in korean online public access catalog (온라인 열람목록의 주제탐색 강화를 위한 실험적 연구)

  • 장혜란;홍지윤
    • Journal of Korean Library and Information Science Society
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    • v.25
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    • pp.83-107
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    • 1996
  • The purpose of this study is to experiment online public access catalog enhancements to improve its subject access capability. Three catalog databases, enhanced with title keywords, controlled vocabulary, and content words with controlled vocabulary respectively, were implemented. 18 searchers performed 2 subject searshes against 3 different catalog databases. And the transaction logs are analyzed. The results of the study can be summarized as follows : Controlled vocabulary catalog database achieved 41.8% recall ratio in average ; the addition of table of contents words to the controlled vocabulary is an effective technique with increasing recall ration upto 55% without decreasing precision ; and the database enhanced with title keywords shows 31.7% recall ratio in average. Of the three kinds of catalog databases, only the catalog with contents words produced 2 unique relevant documents. The results indicate that both user training and system development is required to have better search performance in online public access catalog.

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MPI: A Practical Index Scheme for XML Data in Object Databases

  • Song Ha-Joo
    • Journal of Korea Multimedia Society
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    • v.8 no.6
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    • pp.729-734
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    • 2005
  • In order to access XML data stored in object databases, an efficient index scheme is inevitable. There have been several index schemes that can be used to efficiently retrieve XML data stored In object databases, but they are all the single path indexes that support indexing along a single schema path. Henee, if a query contains an extended path which is denoted by wild character ('*'), a query processor has to examine multiple index objects, resulting in poor performance and inconsistent index management. In this paper, we propose MPI (Multi-Path Index) scheme as a new index scheme that provides the functionality of multiple path indexes more efficiently, while it uses only one index structure. The proposed scheme is easy to manage since it considers the extended path as a logically single schema path. It is also practical since it can be implemented by little modification of the B -tree index structure.

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