• 제목/요약/키워드: Meta Data System

검색결과 360건 처리시간 0.029초

분산 디렉토리 데이터베이스 시스템에서의 메타 데이터 캐싱 기법 (Meta Data Caching Mechanism in Distributed Directory Database Systems)

  • 이강우;고진광
    • 한국정보처리학회논문지
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    • 제7권6호
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    • pp.1746-1752
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    • 2000
  • In this paper, a cache mechanism is proposed to improve the speed of query processing in distributed director database systems. To decrease search time of requested objects and query processing time. query requests and results about objects in a remote site are stored in the cache of a local site. Cache system architecture is designed according to the classified information. Cache schema are designed for each cache information. Operational algorithms are developed for meta data cache which has meta data tree. This tree improves the speed of query processing by reducing the scope of search space. Finally, performance evaluation is performed by comparing the proposed cache mechanism with X500.

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한국어 교육 멀티미디어 자료의 유형과 구축 방식 - 누리-세종학당의 '디지털 자료관' 구축을 위하여 - (Types and Construction Method of Multimedia Materials for the Korean Language Education: For the Construction of Digital Library on Nuri-Sejonghakdang)

  • 이현주;조태린
    • 한국어교육
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    • 제23권1호
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    • pp.25-45
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    • 2012
  • The purpose of this article is to examine types and construction method of multimedia materials for the Korean language education, finally in order to construct digital library on Nuri-Sejonghakdang. Firstly, this article reviews some major concepts such as teaching material, multimedia, learning object, meta-data, reusability, etc. Secondly, various multimedia materials are divided into three types(namely, example material, explanation material, training and evaluating material) according to their characteristics as a learning objects. And then, this article tries to propose the classification-search system and meta-data elements for effective search and use of multimedia materials. Finally, this article is concluded by presenting the long-term plan of digital library construction on Nuri-Sejonghakdang and some follow-up task of this study.

협업을 위한 XMDR-DSM 시스템 설계에 관한 연구 (A Study on XMDR-DSM System Design for Cooperative)

  • 문석재;정계동;최영근
    • 정보처리학회논문지D
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    • 제16D권5호
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    • pp.701-714
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    • 2009
  • 서비스 기반의 전사적 데이터 통합은 기업 변화의 가속화에 따른 통합적인 데이터 관리가 필요하다. 기업 간 협업은 비즈니스 프로세스를 이용하여 분산된 데이터베이스들에 접근하여 이루어진다. 이러한 접근은 글로벌 쿼리 기반으로 수행되기 때문에 이기종간의 상호운용을 위해서 데이터 이질성, 스키마 이질성, 유효성 검증과 같은 문제가 선결되어야 한다. 따라서 협업은 동적이면서 신뢰성 있는 구조를 갖추어야 한다. 본 논문에서는 협업을 위한 XMDR-DSM(eXtended MetaData Registry-Data Service Mediator) 시스템을 제안한다. XMDR-DSM은 XMDR-DS와 XMDR-DQP, XMDR-DAI로 구성되어 글로벌 스키마와 로컬 스키마간의 매핑을 지원해주고, 데이터 접근 및 통합 서비스를 제공한다. 따라서 이기종 데이터베이스 상호간의 업무 지원이 가능하게 하고, 정보를 재활용 가능한 자산으로 확보할 수 있는 이점과 교환의 표준화를 제시할 수 있다. 그리고 워크플로우 기반의 비즈니스 프로세스 제공할 수 있으므로 일원화된 정보를 관리할 수 있게 된다. 따라서 정보 수명을 증대하고 비용절감을 할 수 있게 된다.

Ginseng consumption and risk of cancer: A meta-analysis

  • Jin, Xin;Che, Dao-biao;Zhang, Zhen-hai;Yan, Hong-mei;Jia, Zeng-yong;Jia, Xiao-bin
    • Journal of Ginseng Research
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    • 제40권3호
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    • pp.269-277
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    • 2016
  • Background: The findings of currently available studies are not consistent with regard to the association between the risk of cancer and ginseng consumption. Therefore, we aimed to evaluate this association by conducting a meta-analysis of different studies. Methods: To systematically evaluate the effect of ginseng consumption on cancer incidence, six databases were searched, including PubMed, Ovid Technologies, Embase, The Cochrane Library, China National Knowledge Infrastructure, and Chinese VIP Information, from 1990 to 2014. Statistical analyses based on the protocol employed for a systematic review were conducted to calculate the summary relative risks (RRs) and 95% confidence intervals (CIs). Results: We identified nine studies, including five cohort studies, three case-control studies, and one randomized controlled trial, evaluating the association between ginseng consumption and cancer risk; these studies involved 7,436 cases and 334,544 participants. The data from the meta-analysis indicated a significant 16% lower risk of developing cancer in patients who consumed ginseng (RR = 0.84, 95% CI = 0.76-0.92), with evidence of heterogeneity (p = 0.0007, $I^2$ = 70%). Stratified analyses suggested that the significant heterogeneity may result from the incidence data for gastric cancer that were included in this study. Publication bias also showed the same result as the stratified analyses. In addition, subgroup analyses for four specific types of cancer (colorectal cancer, lung cancer, gastric cancer, and liver cancer) were also performed. The summary RRs for ginseng intake versus no ginseng consumption were 0.77 for lung cancer, 0.83 for gastric cancer, 0.81 for liver cancer, and 0.77 for colorectal cancer. Conclusion: The findings of this meta-analysis indicated that ginseng consumption is associated with a significantly decreased risk of cancer and that the effect is not organ specific.

Structural health monitoring through meta-heuristics - comparative performance study

  • Pholdee, Nantiwat;Bureerat, Sujin
    • Advances in Computational Design
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    • 제1권4호
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    • pp.315-327
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    • 2016
  • Damage detection and localisation in structures is essential since it can be a means for preventive maintenance of those structures under service conditions. The use of structural modal data for detecting the damage is one of the most efficient methods. This paper presents comparative performance of various state-of-the-art meta-heuristics for use in structural damage detection based on changes in modal data. The metaheuristics include differential evolution (DE), artificial bee colony algorithm (ABC), real-code ant colony optimisation (ACOR), charged system search (ChSS), league championship algorithm (LCA), simulated annealing (SA), particle swarm optimisation (PSO), evolution strategies (ES), teaching-learning-based optimisation (TLBO), adaptive differential evolution (JADE), evolution strategy with covariance matrix adaptation (CMAES), success-history based adaptive differential evolution (SHADE) and SHADE with linear population size reduction (L-SHADE). Three truss structures are used to pose several test problems for structural damage detection. The meta-heuristics are then used to solve the test problems treated as optimisation problems. Comparative performance is carried out where the statistically best algorithms are identified.

High Performance Computing 환경을 위한 고성능, 무정지 파일시스템 구현 (The development of the high effective and stoppageless file system for high performance computing)

  • 박영배;최승환;이상호;김경수;공용준
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2004년도 추계 종합학술대회 논문집
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    • pp.395-401
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    • 2004
  • In the current high network-centralized computing and enterprising environment, it is getting essential to transmit data reliably at very high rates. Until now previous client/server model based NFS(Network File System) or AFS(Andrew's Files System) have met the various demands but from now couldn't satisfy those of the today's scalable high-performance computing environment. Not only performance but data sharing service redundancy have risen as a serious problem. In case of NFS, the locking issue and cache cause file system to reboot and make problem when it is used simply as ip-take over for H/A service. In case of AFS, it provides file sharing redundancy but it is not possible until the storage supporting redundancy and equipments are prepared. Lustre is an open source based cluster file system developed to meet both demands. Lustre consists of three types of subsystems : MDS(Meta-Data Server) which offers the meta-data services, OST(Objec Storage Targets) which provide file I/O, and Lustre Clients which interact with OST and MDS. These subsystems with message exchanging and pursuing scalable high-performance file system service. In this paper, we compare the transmission speed of gigabytes file between Lustre and NFS on the basis of concurrent users and also present the high availability of the file system by removing more than one OST in operation.

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학술지 메타데이터의 표준화 체계에 관한 비교 연구 (A Comparative Study of Metadata Standards for Serials)

  • 한성국;이현실
    • 한국도서관정보학회지
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    • 제36권1호
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    • pp.415-440
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    • 2005
  • 본 연구는 의미적 상호운용이 가능한 학술지 공동이용 시스템 구축에 기초자료 제공을 목적으로 학술지의 메타데이터 시스템의 체계에 관해 분석하였다. 학술지 정보의 특성을 고려하여 학술지 메타데이터 형식을 학술지 식별자 정보, 학술지 서지정보와 학술지 소장정보로 구분하여 고찰하였다. 학술지 식별자 정보는 학술지에 정보관리 시스템의 주요키로서, 디지털정보 매체가 일반화되고 있는 시점에 이에 대한 고려가 중요하다. 학술지 서지정보 형태는 전통적으로 MARC 포맷을 활용하여 왔지만, 앞으로 MARC의 풍부한 메타데이터 요소와 DCMI의 간편성을 조화시킨 서지정보 표현 방식이 필요하다. 학술지 소장정보 표현에는 ANSI/NISO Z39.71 등 최근에 제안된 메타데이터 표준안이 간편하면서 다양한 소장 형태를 표현하기에 적합하며, 제공하는 학술지 정보 서비스 형태에 따라 기술 수준의 정도가 차별화 되어야 한다. 현재의 컴퓨터 기술은 정보의 표현과 처리가 XML 중심이기 때문에, 학술지 메타데이터 기술도 XML 기반이어야 한다.

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A Comparison of Meta-learning and Transfer-learning for Few-shot Jamming Signal Classification

  • Jin, Mi-Hyun;Koo, Ddeo-Ol-Ra;Kim, Kang-Suk
    • Journal of Positioning, Navigation, and Timing
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    • 제11권3호
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    • pp.163-172
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    • 2022
  • Typical anti-jamming technologies based on array antennas, Space Time Adaptive Process (STAP) & Space Frequency Adaptive Process (SFAP), are very effective algorithms to perform nulling and beamforming. However, it does not perform equally well for all types of jamming signals. If the anti-jamming algorithm is not optimized for each signal type, anti-jamming performance deteriorates and the operation stability of the system become worse by unnecessary computation. Therefore, jamming classification technique is required to obtain optimal anti-jamming performance. Machine learning, which has recently been in the spotlight, can be considered to classify jamming signal. In general, performing supervised learning for classification requires a huge amount of data and new learning for unfamiliar signal. In the case of jamming signal classification, it is difficult to obtain large amount of data because outdoor jamming signal reception environment is difficult to configure and the signal type of attacker is unknown. Therefore, this paper proposes few-shot jamming signal classification technique using meta-learning and transfer-learning to train the model using a small amount of data. A training dataset is constructed by anti-jamming algorithm input data within the GNSS receiver when jamming signals are applied. For meta-learning, Model-Agnostic Meta-Learning (MAML) algorithm with a general Convolution Neural Networks (CNN) model is used, and the same CNN model is used for transfer-learning. They are trained through episodic training using training datasets on developed our Python-based simulator. The results show both algorithms can be trained with less data and immediately respond to new signal types. Also, the performances of two algorithms are compared to determine which algorithm is more suitable for classifying jamming signals.

The Association of Circumcision and Prostate Cancer: A Meta-Analysis

  • Li, Yu-dan;Teng, Yang;Dai, Yu;Ding, Hui
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권8호
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    • pp.3823-3827
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    • 2016
  • Background: To investigate the association circumcision with prostate cancer. Materials and Methods: We searched PubMed, EMBASE, the Cochrane Library, and Chinese biomedicine literature database up to August 2015. All case-control studies were identified in which investigated the association circumcision with prostate cancer. Three authors independently assessed study quality and extracted data. All data were analyzed using RevMan 5.3 and STATA version 11.0. Results: Six case-control studies met the inclusion criteria. The pooled meta-analysis showed that there was a lower incidence of circumcision in prostate cancer patients compared with control (OR=0.90, 95% confidence interval [CI] 0.82-0.98, P=0.01). The results of meta-analysis also showed that no significant difference was found between circumcision and less aggressive prostate cancer (OR=0.93, 95% CI 0.83-1.04, P=0.19); however, there was a lower incidence of circumcision in more aggressive prostate cancer compared with control (OR =0.84, 95% CI 0.72-0.97, P=0.02). The Egger's results did not show any evidence of publication bias(P=0.798). Conclusions: In summary, within the limits of available data, male with circumcision appears to have a lower incidence of prostate cancer. In the future, high-quality multicenter studies are needed to thoroughly verify the outcome.

A Formal Specification and Meta-Model for Development of Cooperative Collection·Analysis Framework

  • Cho, Eun-Sook;Song, Chee-Yang
    • 한국컴퓨터정보학회논문지
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    • 제24권12호
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    • pp.85-92
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    • 2019
  • 기업들은 소셜 미디어로부터 특정 주제 및 자사 제품에 대한 다수의 사용자들의 의견을 수집하고 분석하여 사용자 집단이나 소비 트렌드를 식별할 수 있고, 이를 기반으로 미래 예측 및 마케팅 등의 다양한 목적으로 활용하고 있다. 따라서 현재 소셜 미디어 분석 도구들이 네트워크 통계 분석을 통해 기업의 소셜 미디어 마케팅의 성과를 측정하기 위한 수단으로 사용되고 있다. 그러나 이러한 도구들은 방대한 양의 소셜 미디어 데이터를 수집하고 이를 분석하기 위해 고가의 컴퓨팅 자원 및 네트워크 자원을 소모하고, 복잡한 소프트웨어 플랫폼 구축 및 운용에 따른 비용 부담과 많은 운영 노하우를 필요로 한다. 그 결과 중소기업이나 개인 사업자의 경우는 이러한 소셜 미디어 데이터를 효율적으로 활용하지 못하는 어려움이 있다. 따라서 본 논문에서는 중소기업이나 개인 컴퓨터에서도 운영이 가능한 소셜 미디어 데이터 수집 및 분석 시스템 개발에 필요한 프레임워크 설계와 제시된 프레임워크 설계에 대한 완전성이나 일관성을 검증하기 위한 정형 명세 기법을 제시한다. 또한 정형명세 기법으로 Z 언어를 통해 명세한 결과를 Z-EVES Tool을 통해 Z 모델 체킹을 수행하여 프레임워크 설계의 명확성을 검증한다.