• Title/Summary/Keyword: Data-driven Research

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Conceptual Design Method and Program Development Study on Compound Gyroplane with Rotor and Wing (자전형 로터를 갖는 복합 자이로플레인 개념설계 기법과 프로그램 개발에 관한 연구)

  • Lee, Young-Jae;Kim, Ji-Min;Vu, Ngoc Anh;Lee, Jae-Woo;Chung, In-Jae
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.18 no.3
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    • pp.1-8
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    • 2010
  • A design study has been performed to obtain configuration and weight of a compound gyroplane. A study of research trends and characteristics was performed to develop the compound gyroplane sizing program. Based on these results, the sizing program has been developed and its suitability has been validated using existing compound gyroplane data. The subject air vehicles was a Challis Heliplane UAV, Carter Coptet, FB-1 Gyrodyne, and Jet Gyrodyne. As results, the program was suitable to size a compound gyroplane at conceptual design phase, because the greatest error rate was less than 10% and the conceptual design allowance error rate is less than 15%.

A framework for selecting information systems planning (ISP) approach (ISP 방법론 비교 선정을 위한 프레임워크)

  • Sung Kun Kim;Soon Sam Hwang
    • Journal of Information Technology Applications and Management
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    • v.9 no.3
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    • pp.129-139
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    • 2002
  • There exist a number of information systems planning (ISP) methodologies. Historically these methodologies have been evolving to reflect new technologies and business requirements. In fact, it is an uneasy task to select a methodology that fits a business need. Though there have been a number of studies proposing new ISP approaches, we are unable to find much research doing a comparative analysis on existing ISP methodologies. Our study, therefore, is to present a classification scheme for ISP approaches and to provide a guideline framework for selecting an approach most suitable to a particular firm's need. Our classification utilizes types of components covered in ISP deliverables and the peculiarity of these components. Such classification scheme and selection framework would help derive an IT-driven new enterprise model more effectively.

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Development and Testing of Satellite Operation System for Korea Multipurpose Satellite-I

  • Mo, Hee-Sook;Lee, Ho-Jin;Lee, Seong-Pal
    • ETRI Journal
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    • v.22 no.1
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    • pp.1-11
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    • 2000
  • The Satellite Operation System (SOS) has been developed for a low earth orbiting remote sensing satellite, Korea Multipurpose Satellite-I, to monitor and control the spacecraft as well as to perform the mission operation. SOS was designed to operate on UNIX in the HP workstations. In the design of SOS, flexibility, reliability, expandability and interoperability were the main objectives. In order to achieve these objectives, a CASE tool, a database management system, consultative committee for space data systems recommendation, and a real-time distributed processing middle-ware have been integrated into the system. A database driven structure was adopted as the baseline architecture for a generic machine-independent, mission specific database. Also a logical address based inter-process communication scheme was introduced for a distributed allocation of the network resources. Specifically, a hotstandby redundancy scheme was highlighted in the design seeking for higher system reliability and uninterrupted service required in a real-time fashion during the satellite passes. Through various tests, SOS had been verified its functional, performance, and inter-face requirements. Design, implementation, and testing of the SOS for KOMPSAT-I is presented in this paper.

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Mergers and radio-loud active galaxies: connecting the dots

  • Karouzos, M.;Britzen, S.;Zensus, A.J.;Eckart, A.;Jarvis, M.;Bonfield, D.
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.34.2-34.2
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    • 2012
  • In the context of structure formation in a hierarchical Universe, the relevance of mergers to radio-loud active galaxies is still under debate. I employ two different observational approaches to investigate the merger history of active galaxies, using several different samples of radio-loud AGN. I will first show results from the investigation of a complete sample of flat-spectrum radio-AGN and their role in a merger-driven evolution of galaxies. In the second part of my talk I will focus on the investigation of the close environment of radio-loud active galaxies, using data from the new VISTA-VIDEO near-infrared survey. Strong evidence is found supporting a close connection between merger events and radio-loud AGN.

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Generation of Simulation Input Data Using Threshold Bootstrap (임계값 붓스트랩을 사용한 입력 시나리오의 생성)

  • Kim Yun-Bae;Kim Jae-Bum;Ko Jong-Suk
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.05a
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    • pp.1179-1185
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    • 2003
  • 시뮬레이션 상의 입력모델에 대한 기존의 연구는 과거의 자료를 바탕으로 선형의 모수적인 (parametric) 모형을 개발하는데 초점을 두고 있다. 그러나 이 경우에는 입력이 매우 복잡한 형태를 가지면 모수적인 모형을 잦는 것이 불가능해지므로 비모수적인(non-parametric) 접근방법이 절실한 실정이다 예로 인터넷 트래픽 모델의 시뮬레이션 수행시 입력으로 제공되는 단위 시간당 요구되는 웹 페이지의 수 같은 경우 데이터들 간데 종속관계가 매우 심하고 복잡하여 모수적 모형을 세우는데 어려움이 있다. 이러한 시스템들을 시뮬레이션 방법으로 분석 하고자 할 때, 기존의 trace-driven 시뮬레이션 방법이나 모수적 모형을 찾아 다수의 사실적인 시뮬레이션 입력 자료를 확보하는 것은 현실적으로 어려움이 있다. 따라서. 비모수적인 방법으로 다수의 사실적인 시뮬레이션 입력 자료를 생성하는 것이 필요하다. 이러한 비모수적인 방법에 대한 평가기준 설정은 시뮬레이션 상의 입력 모델에 대한 타당성을 제시한다는 점에서 또한 매우 중요하다. 본 논문에서는 붓트스트 랩의 방법중의 하나인 임계값 붓트스트랩을 이용하여 시뮬레이션 입력 자료 생성 방법을 개발하였고 Turing test를 통해 붓스트랩으로 생성산 입력 시나리오를 검증하였다.

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ANALYSIS OF SMOKE SPREAD EFFECT DUE TO THE FIRE STRENGTH IN UNDERGROUND SUBWAY-STATION (대심도 역사의 화재강도에 따른 연기확산 영향 분석)

  • Jang, Yong-Jun;Koo, In-Hyuk;Kim, Hag-Beom;Kim, Jin-Ho
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.373-378
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    • 2011
  • As the number of deeply-underground subway station(DUSS) increases, the safety measures for DUSS have been requested. In this research, Shingumho station (The line # 5, Depth: 46m) has been selected as case-study for the analysis of smoke-spread speed with the different fire strength. Field test data measured for actual fan in DUSS was applied as a condition of a simulation. The whole station was covered in this analysis and total of 4 million grids were generated for this simulation. The fire driven flow was analyzed case by case to compare the smoke-spread effect according to the fire strength. in order to enhance the efficiency of calculation, parallel processing by MPI was employed and large eddy simulation method in FDS code was adopted.

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Mining Parallel Text from the Web based on Sentence Alignment

  • Li, Bo;Liu, Juan;Zhu, Huili
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2007.11a
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    • pp.285-292
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    • 2007
  • The parallel corpus is an important resource in the research field of data-driven natural language processing, but there are only a few parallel corpora publicly available nowadays, mostly due to the high labor force needed to construct this kind of resource. A novel strategy is brought out to automatically fetch parallel text from the web in this paper, which may help to solve the problem of the lack of parallel corpora with high quality. The system we develop first downloads the web pages from certain hosts. Then candidate parallel page pairs are prepared from the page set based on the outer features of the web pages. The candidate page pairs are evaluated in the last step in which the sentences in the candidate web page pairs are extracted and aligned first, and then the similarity of the two web pages is evaluate based on the similarities of the aligned sentences. The experiments towards a multilingual web site show the satisfactory performance of the system.

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Goodness-of-Fit Test Based on Smoothing Parameter Selection Criteria

  • Kim, Jong-Tae
    • Communications for Statistical Applications and Methods
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    • v.2 no.1
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    • pp.122-136
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    • 1995
  • The objective of this research is to investigate the problem of goodness-of-fit testing based on nonparametric density estimation with a data-driven smoothing parameter. The small and large sample properties of a new test statistic $\hat{\lambda_a}$ is investigated. The test statistic $\hat{\lambda_a}$ is itself a smoothing parameter which is selected to minimize an estimated MISE for a truncated series estimator of the comparison density function. Therefore, this test statistic leads immediately to a point estimate of the density function th the event that $H_0$ is rejected. The limiting distribution of $\hat{\lambda_a}$ is obtained under the null hypothesis. It is also shown that this test is consistent against fixed alternatives.

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Trends of Simulated Reality Driven by Big Data (빅데이터 기반 모사현실 기술동향)

  • Ahn, C.W.;Paik, E.H.;Kim, K.H.;Hwang, S.K.
    • Electronics and Telecommunications Trends
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    • v.31 no.5
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    • pp.120-130
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    • 2016
  • 21세기 디지털 사회에서는 각 개인의 연결과 상호작용이 사회 현상에 막대한 영향을 미치고 있으며, 이로 인해 사회는 더욱 복잡해지고, 순간적으로 급격한 변화가 일어나는 현상이 빈번히 발생한다. 사회 복잡성(Social Complexity)은 다수의 사회 구성원들 간의 복잡한 연결로 인해 발생하는 상호작용 패턴을 의미한다. 2011년 발생한 '아랍의 봄' 혁명, 글로벌 금융위기, 조류독감의 발생과 확산, 글로벌 기후 변화, 테러리스트들의 네트워크와 사이버 범죄의 증가 등은 복잡하게 연결된 글로벌 사회 현상으로 발생하는 복잡성의 사례들이다. 우리 사회의 안전성과 지속성을 확보하기 위해, 이러한 사회 복잡성을 그려내어, 그 속에 숨겨진 패턴을 분석하고 예측하는 기술에 대한 연구 개발이 국가적으로 필요하다. 다양한 분야의 사회적 모형을 개발하고 서로 연결하여, 복잡한 사회적 상호작용을 대규모 시뮬레이션을 통해 현상 분석과 사회경제 정책적 대응방향에 대한 통찰력을 가질 수 있는 대규모 '모사현실(Simulated Reality)' 기술 개발을 서둘러야 한다.

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Internet Based Intelligent Survey and Application System (지능형 웹기반 설문 및 원서 접수시스템)

  • So Yo-Hwan;Kim Seok-Soo
    • Journal of Digital Contents Society
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    • v.5 no.1
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    • pp.54-60
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    • 2004
  • This research employs the intelligent survey agent and online application from to help people to locate the information they would want from Internet quickly. Corporate sectors and indivisuals are in need of valuable and relevant information to swiftly adapt to the Internet-driven business or educational environment. Based on Internet GUI environment, this user-friendly online survey and online application form program uses the agent of increasing the interest and participation of users. The system helps along with the decision making process by quickening the information gathering process.

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