• 제목/요약/키워드: Top-down Approach

검색결과 213건 처리시간 0.028초

MAO 모델을 사용한 관계 데이타베이스의 논리적 설계방법론 (A Logical Design Methodology for Relational Databases Using the MAO (Multiple Aspects-based Object) Model)

  • 조동영;백두선;황종선
    • 한국경영과학회지
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    • 제16권2호
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    • pp.49-64
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    • 1991
  • In this paper, we present a stepwise design methodology for relational databases using a new conceptual data model, the MAO(Multiple Aspects-based Object) model. Our methodology consists two steps : first, data requirements are conceptualized using the MAO model with concepts such as objects types and aspect types : second, the MAO model is transformed into the third normal form inn the relational model supported by commercial DBMs. A top-down approach is used for the MAO modelling in the first, step, and the transformation process in the second step can be automated. Our methodology supports easier and more database design of real world than other methodologies using existing data models.

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데이터 웨어하우스 구축을 위한 상향식.하향식 접근 방법에 관한 연구 - 방법론적 고찰을 통한 접근

  • 박주석;전대성;박진휘
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1998년도 추계학술대회 논문집
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    • pp.15-18
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    • 1998
  • Recently, domestic datawarehouse marketplaces take up the most important part of information technology investments with ERP(Enterprise Resource Planning), EC(Electronic Commerce) construction projects in spite of a business slowdown for IMF environment. Therefore, in industrial fields as finances, communications, manufactures, distributions, and so on, datawarehouse was constructed or is under construction, and datawarehouse success stories was showed around some enterprises that has constructed previously datawarehouse. This study is intended to be henceforth an index and direction for an actual proof study by discussing a study of methodology for datawarehouse construction in order to compare and analyze Top-down & Bottom-up approach for datawarehouse that has constructed in actual enterprises.

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메시지 의미관계를 이용한 프로토콜 변환 방법에 관한 연구 (A Study on the Protocol Conversion Method using Semantic Relation between Messages)

  • 권운철;심영섭;이동호
    • 한국통신학회논문지
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    • 제19권6호
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    • pp.1107-1114
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    • 1994
  • 본 논문은 적합성을 만족하는 프로토콜 변환 방법에 메시지간의 의미관계를 추가하여 프로토콜 변환기를 생성하는 방법을 제시한다.. 특히, 제안된 방법은 정형화된 기법과 하향식 방법을 도입하여 서로 다른 포로토콜로 구현된 컴퓨터 네트워크 사이의 프로토콜 불일치를 해결하는 효율적인 최다(maximal) 변환기를 유도한다. 따라서 제시된 방법을 사용하여 변환기를 유도할 경우, 불필요한 상태나 전이들의 상당 부분이 쉽게 제거된다.

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웹기반의 경량전철 유지보수 정보화시스템 개발방법론에 대한 연구 (A Study on the methodology for Web-based Maintenance System Development of Light Rail Transit)

  • 이호용;한석윤;조홍식;조봉관
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.722-729
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    • 2007
  • The methodology for maintenance system development should overall be considered with all of task characteristic, schedule, and the technical condition of investment sources. This research applies Waterfall model to methodology for the development and construction of maintenance system through customizing the CD (Custom Development) procedure of "HSDM (Hyundai System Development Methodology)" based on information engineering. The waterfall model called as classic life cycle paradigm is defined for the sequent development procedure, which make progress a next step after that a previous step is admitted with thorough review. This model which is popular and the oldest paradigm is used for system development by four steps; demands analysis, design, construction, and maintenance. This methodology advances higher abstract step from higher lower step using top-down approach from concept definition to construction, which notices the end of a step whenever a step is over. Therefore, each step is exactly divided, and consequently the output is clearly yielded.

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Nanohole Fabrication using FIB, EB and AFM for Biomedical Applications

  • Zhou, Jack;Yang, Guoliang
    • International Journal of Precision Engineering and Manufacturing
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    • 제7권4호
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    • pp.18-22
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    • 2006
  • Although many efforts have been made in making nanometer-sized holes, there is still a major challenge in fabricating individual single-digit nanometer holes in a more controllable way for different materials, size distribution and hole shapes. In this paper we describe our efforts to use a top down approach in nanofabrication method to make single-digit nanoholes. There are three major steps towards the fabrication of a single-digit nanohole. 1) Preparing the freestanding thin film by epitaxial deposition and electrochemical etching. 2) Making sub-micro holes ($0.2{\mu}\;to\;0.02{\mu}$) by focused ion beam (FIB), electron beam (EB), atomic force microscope (AFM), and others methods. 3) Reducing the hole size to less than 10 nm by epitaxial deposition, FIB or EB induced deposition and micro coating. Preliminary work has been done on thin films (30 nm in thickness) preparation, sub-micron hole fabrication, and E-beam induced deposition. The results are very promising.

Stretchable and Foldable Electronics by Use of Printable Single-Crystal Silicon

  • 안종현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.29-29
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    • 2008
  • Realization of electronics with performance equal to established technologies that use rigid semiconductor wafers, but in lightweight, foldable and stretchable formats would enable many new application possibilities. Examples include wearable systems for personal health monitoring, 'smart' surgical gloves with integrated electronics and electronic eye type imagers that incorporate focal plane arrays on hemispherical substrates. Circuits that use organic or certain classes of inorganic electronic materials on plastic or steel foil substrates can provide some degree of mechanical flexibility, but they cannot be folded or stretched. Also, with few exceptions such systems offer only modest electrical performance. In this talk, I will present a new approach to high performance, flexible and stretchable integrated circuits. These systems combine single-crystal silicon nanoribbons with thin plastic or elastomeric substrates using both "top-down" and "transfer-printing" technologies. The strategies represent promising routes to high performance, flexible and stretchable optoelectronic devices that can incorporate established, high performance inorganic electronic materials.

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An Application of Virtual Reality in E-learning based LEGO-Like Brick Assembling

  • Tran, Van Thanh;Kim, Dongho
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2016년도 춘계학술발표대회
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    • pp.783-786
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    • 2016
  • E-learning is a new teaching model nowadays, and Virtual Reality (VR) technology is reported that the use of virtual reality as an education tool can increase student interests, understanding, and creative learning because of encouraging students to learn by exploring and interacting with the information on the virtual environment. Besides that, LEGOs have long been the favorite of many children. LEGOs provide a mechanism to understand and do for many concepts from spatial relationships to robotics platforms. In this paper, we present a virtual reality application based on the assembly of LEGO-Like bricks to increase math and science learning by improving spatial thinking. It not only encourages students to pursue careers in science, technology, engineering, or mathematics but also enhances learner's ability to analyze and solve problems. The application is built by Processing 2.0 as the easier programming language which is a top-down approach to build the 3D interactive program.

연간수요예측시스템의 개발 (Development of An Yearly Load Forecasting System)

  • 추진부;이철휴;전동훈;김성학;황갑주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 B
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    • pp.908-912
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    • 1996
  • The yearly load forecasting system has been developed for the economic and secure operation of electric power system. It forecasts yearly peak load and thereafter deduces hourly load using the top-down approach. Relative coefficient model has been applied to estimate peak load of a specific date or a specific day of the week. It is equipped with graphic user interface which enables a user to easily access to the system. Yearly average forecasting error may be reduced to $2{\sim}3$(%) only if we can forecast summer-time temperature correctly.

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업무용 부문의 DSM 장재량 평가절차 및 절전잠재량 추정 (DSM Potential Evaluation and Estimation of Commercial Sector)

  • 박종진;이창호;조인승
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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    • pp.253-255
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    • 1998
  • This paper presents the methodology of DSM potential evaluation and estimation of commercial sector in Korea. In general, the estimation process of the potential savings of DSM activities include the determination of baseline electricity consumption, the instantaneous technical potential (ITP), the phased technical potential (PTP), the economic potential (EP), and the achievable potential(AP). The purpose of this paper is to provide evaluation process of those DSM potential savings based on top-down approach and apply it to commercial sector.

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선로그래프를 이용한 철도망 위상 표현방법 (Representation Method of Track Topologies using Railway Graph)

  • 조동영
    • 한국멀티미디어학회논문지
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    • 제5권1호
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    • pp.114-119
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    • 2002
  • 철도선로망 제어시스템에서 신속한 철도선로의 배정은 실시간 선로배정의 중요한 요소인데, 이 문제의 해결을 위해서는 먼저 철도 선로망의 위상을 정확하게 표현해야 한다. 그래프는 망 구조를 표현하는데 적절한 자료구조이지만 철도 선로망을 표현하는 데에는 부적절하다. 이 논문에서는 철도 선로망의 위상구조를 정확하게 표현할 수 있는 새로운 자료구조인 선로그래프(railway graph) 개념을 정의한다. 그리고 정의된 선로그래프에서의 경로탐색 알고리즘과 선로그래프를 이용한 하향식 철도 선로망 모델링 방법을 설명한다.

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